Title page

Contents

Acknowledgements 3

Executive Summary 17

Vehicle Technologies Office Overview 102

Annual Progress Report 102

Organization Chart 103

Batteries Program Overview 104

Introduction 104

Goals 104

State of the Art 105

Battery Technology Barriers 107

Program Organization Matrix 107

Battery Highlights from FY 2019 109

I. Advanced Battery and Cell R&D 123

I.1. USABC Battery Development & Materials R&D 123

I.1.A. High-Performance Semi-Solid Cell for EV Applications (24M Technologies, Inc.) 123

I.1.B. Development of High Performance Li-ion Cell Technology for EV Applications (Farasis Energy) 129

I.1.C. Rapid Commercialization of High Energy Anode Materials (SiNode Systems) 135

I.1.D. Li-Ion Cell Manufacturing Using Directly Recycled Active Materials (Farasis Energy) 140

I.1.E. A Closed Loop Recycling Process for End-of-Life Electric Vehicle Li-ion Batteries-Phase II (Worcester Polytechnic Institute) 150

I.1.F. Perform USABC/USCAR Benchmarking Activities (Southwest Research Institute) 156

I.1.G. Fast-Charge and Low-Cost Lithium Ion Batteries for Electric Vehicle Applications (Zenlabs Energy) 161

I.1.H. Enabling Thicker Cathode Coatings for Lithium Ion EV Batteries (PPG Industries) 167

I.2. Processing Science and Engineering 175

I.2.A. Low-cost Manufacturing of Advanced Silicon-Based Anode Materials (Group14 Technologies, Inc.) 175

I.2.B. Electrodeposition for Low-Cost, Water-Based Electrode Manufacturing (PPG Industries, Navitas, ORNL) 180

I.2.C. Towards Solventless Processing of Thick Electron-Beam (EB) Cured LIB Cathodes (ORNL) 186

I.2.D. Performance Effects of Electrode Processing for High-Energy Lithium-Ion Batteries (ORNL) 192

I.2.E. Process R&D for Next Generation Cathode Materials (ANL) 201

I.2.F. Novel R&D for Manufacturing of SS Electrolyte Materials (ANL) 207

I.2.G. Supercritical Fluids Process R&D for LIB Materials (ANL) 211

I.2.H. Integrated Flame Spray Process for Low Cost Production of Battery Materials for Lithium Ion Batteries and Beyond (University of Missouri) 216

I.2.I. High Performance Li-Ion Battery Anodes from Electrospun Nanoparticle/Conducting Polymer Nanofibers (Vanderbilt University) 222

I.2.J. Continuous Flow R&D for Advanced Electrolytes (ANL) 227

I.2.K. Optimizing Co-sintering of Ceramic Components for Manufacturing of All-Solid-State Lithium-Ion Battery (LLNL) 234

I.2.L. Structure-Activity Relationships in the Optimizing Electrode Processing Streams for LiBs (LBNL) 239

I.2.M. Fabricate and test solid-state ceramic electrolytes and electrolyte/cathode laminates (LBNL) 241

I.2.N. Higher Energy Density via Inactive Components and Processing Conditions (LBNL) 245

I.2.O. Novel data-mining and other AI approaches for synthesis and processing of cathode materials (LBNL) 250

I.2.P. Minimizing Side-Reactions in Next Generation Lithium Ion Battery Cathodes Through Structure-Morphology Optimization (ANL) 255

I.2.Q. High Energy, Long Life Lithium-Ion Battery (NREL) 263

I.2.R. Co-Extrusion (CoEx) for Cost Reduction of Advanced High-Energy-and-Power Battery Electrode Manufacturing (PARC) 270

I.3. Computer-Aided Engineering for Batteries (CAEBAT) 276

I.3.A. Advanced Computer-Aided Battery Engineering Consortium (NREL, ANL, SNL, Purdue Univ.) 276

I.3.B. Consortium for Advanced Battery Simulation (SNL) 285

I.3.C. Advanced Tool for Computer Aided Battery Engineering (ANL) 291

I.3.D. Development and Validation of a Simulation Tool to Predict the Combined Structural, Electrical, Electrochemical and Thermal Responses of Automotive Batteries (Ford Motor Company) 297

I.3.E. Consortium of Advanced Battery Simulation (ORNL) 306

I.4. Recycling and Sustainability 314

I.4.A. Battery Production and Recycling Materials Issues (ANL) 314

I.4.B. Lithium-Ion Battery Recycling Prize Support (NREL) 318

I.4.C. ReCell Advanced Battery Recycling Center (ANL) 326

I.5. Extreme Fast Charging (XFC) 386

I.5.A. High Temperature Electrolytes for Extreme Fast Charging (ANL) 386

I.5.B. XFC R&D: Battery Testing Activities (INL) 392

I.5.C. XFC R&D: MSMD Modeling & Thermal Testing (NREL) 398

I.5.D. Research on high power, doped titanium-niobium oxide anodes (ORNL) 411

I.5.E. Research three-dimensional hierarchical graphite architectures for anodes for fast charging (SNL) 417

I.5.F. Develop new electrolyte additives, optimized active materials, and electrode formulations (ANL) 424

I.5.G. Enabling Extreme Fast Charging through Control of Li Deposition Overpotential on Graphite Electrodes (Stony Brook University) 430

I.5.H. Detecting Lithium Plating during Fast Charging, Heterogeneity Effects during Fast Charging, and Graphite Anodes with Directional Pore Channels Made by Freeze Tape Casting (LBNL) 437

I.5.I. Novel Electrolyte Development with High Lithium-Ion Transference Number (Hi-LiT) for Extreme Fast Charging (ORNL) 446

I.5.J. New High-Energy & Safe Battery Technology with Extreme Fast Charging Capability for Automotive Applications (Microvast, Inc.) 452

I.5.K. XFC R&D: CAMP, Testing & Post-Test Characterization and Modeling (ANL, SLAC) 456

I.6. Beyond Batteries 465

I.6.A. Behind-the-Meter Storage (NREL, INL, ORNL, SNL) 465

I.7. Testing and Analysis 502

I.7.A. BatPaC Model Development (ANL) 502

I.7.B. Battery Performance and Life Testing (ANL) 509

I.7.C. Battery Safety Testing (SNL) 512

I.7.D. Battery Thermal Analysis and Characterization Activities (NREL) 518

I.7.E. Cell Analysis, Modeling, and Prototyping (CAMP) Facility Research Activities (ANL) 525

I.7.F. Materials Benchmarking Activities for CAMP Facility (ANL) 542

I.7.G. Electrochemical Performance Testing (INL) 550

I.8. Small Business Innovation Research (SBIR) 554

II. Battery Materials R&D 562

II.1. Next Generation Lithium-Ion Batteries: Advanced Anodes 562

II.1.A. Next Generation Anodes for Lithium-Ion Batteries: Silicon (ANL, LBNL, ORNL, SNL, NREL) 562

II.1.B. Silicon Electrolyte Interface Stabilization (SEISta) (NREL, ANL, ORNL, LBNL, SNL) 613

II.1.C. Probe the Relationships between Functional Electrolytes Structure and SEI Property for Si Materials (LBNL) 711

II.1.D. Development of Si-based High-Capacity Anodes (PNNL) 717

II.1.E. Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries (Stanford University) 724

II.2. Next Generation Lithium-Ion Batteries: Advanced Cathodes R&D 729

II.2.A. Diagnostic Testing and Evaluation (ANL, ORNL, NREL) 729

II.2.B. Design, Synthesis, & Characterization of Low-Cobalt Cathodes (ANL, LBNL, PNNL) 755

II.2.C. Theory and Modeling (ANL, LBNL) 771

II.2.D. Design & Synthesis of High Energy, Mn-Rich Oxides for Li-Ion Batteries (ANL) 780

II.2.E. In situ Spectroscopy of Solvothermal Synthesis of Next-Generation Cathode Materials (BNL) 787

II.2.F. Lithium Batteries with Higher Capacity and Voltage (UTA) 794

II.2.G. Disordered RockSalt Structured Cathode Materials: Electrochemistry and Synthesis (LBNL) 800

II.2.H. Disordered RockSalt Structured Cathode Materials: Characterization and Modeling (LBNL, ORNL, PNNL, UC Santa Barbara) 808

II.3. Next Generation Lithium-Ion batteries: Frontier Science at Interfaces 817

II.3.A. Molecular-level Understanding of Cathode-Electrolyte Interfaces (SLAC) 817

II.3.B. Stability of Cathode/Electrolyte Interfaces in High Voltage Li-ion Batteries (ANL) 824

II.3.C. Interfacial Studies of Emerging Cathode Materials (LBNL) 830

II.3.D. Understanding and Modification of High-Energy Cathodes and Their Interfaces with Electrolytes for Next-Generation Li-Ion Batteries (PNNL) 837

II.3.E. Fluorinated Deep Eutectic Solvent (FDES)-Based Electrolytes (ANL) 842

II.3.F. Developing In situ Microscopies for the Model Cathode/Electrolyte Interface (NREL) 849

II.3.G. Advanced Lithium Ion Battery Technology - High Voltage Electrolyte (Daikin America, Inc.) 857

II.4. Next Generation Lithium-Ion batteries: Low-Cobalt/No Cobalt cathodes 866

II.4.A. Aerosol Manufacturing Technology to Produce Low-Cobalt Li-ion Battery Cathodes (Cabot) 866

II.4.B. Cobalt-free Cathode Materials and Their Novel Architectures (UCSD) 873

II.4.C. Novel Lithium Iron and Aluminum Nickelate (NFA) as Cobalt-Free Cathode Materials (ORNL) 883

II.4.D. Enhancing Oxygen Stability in Low-Cobalt Layered Oxide Cathode Materials by Three-Dimensional Targeted Doping (UC Irvine) 890

II.4.E. High-Nickel Cathode Materials for High-Energy, Long-Life, Low-Cost Lithium-Ion Batteries (UTA) 901

II.4.F. Cobalt-Free Cathodes for Next Generation Li-Ion Batteries (Nexceris) 908

II.4.G. High-Performance Low-Cobalt Cathode Materials for Li-ion Batteries (PSU) 914

II.5. Next Generation Lithium-Ion Batteries: Diagnostics 927

II.5.A. Interfacial Processes (LBNL) 927

II.5.B. Advanced in situ Diagnostic Techniques for Battery Materials (BNL) 934

II.5.C. Advanced Microscopy and Spectroscopy for Probing and Optimizing Electrode-Electrolyte Interphases in High Energy Lithium Batteries (UCSD) 942

II.5.D. Microscopy Investigation on the Fading Mechanism of Electrode Materials (PNNL) 950

II.5.E. In Operando Thermal Diagnostics of Electrochemical Cells (LBNL) 955

II.5.F. Solid Electrolyte Interphases on Lithium Metal for Rechargeable Batteries (General Motors) 959

II.5.G. High-Conductivity, Low-Temperature Polymer Electrolytes for Lithium-Ion Batteries (LBNL) 966

II.5.H. Development of High Energy Battery System with 300Wh/kg (ANL) 971

II.5.I. Correlative Microscopy Characterization of Oxide Electrodes (SLAC National Accelerator Laboratory) 980

II.6. Next Generation Lithium-Ion batteries: Modeling Advanced Electrode Materials 985

II.6.A. Electrode Materials Design and Failure Prediction (ANL) 985

II.6.B. Design and Synthesis of Advanced High-Energy Cathode Materials (LBNL) 992

II.6.C. Design of High-Energy, High-Voltage Lithium Batteries through First-Principles Modeling (LBNL) 1000

II.6.D. First Principles Investigation of Existing and Novel Electrode Materials (LBNL) 1005

II.6.E. Addressing Heterogeneity in Electrode Fabrication Processes (Brigham Young University) 1012

II.6.F. Large scale ab initio molecular dynamics simulation of liquid and solid electrolytes (LBNL) 1019

II.6.G. Dendrite Growth Morphology Modeling in Liquid and Solid Electrolytes (MSU) 1025

II.7. Beyond lithium-Ion R&D: Metallic Lithium 1032

II.7.A. Mechanical Properties at the Protected Lithium Interface (ORNL) 1032

II.7.B. Composite Electrolytes to Stabilize Metallic Lithium Anodes (ORNL) 1038

II.7.C. Lithium Dendrite Prevention for Lithium Batteries (PNNL) 1044

II.7.D. Understanding and Strategies for Controlled Interfacial Phenomena in Li-Ion Batteries and Beyond (TAMU, Purdue) 1050

II.7.E. Engineering Approaches to Dendrite Free Lithium Anodes (University of Pittsburgh) 1057

II.7.F. Electrochemically Responsive Self-Formed Li-ion Conductors for High Performance Li Metal Anodes (Penn State University) 1067

II.7.G. Integrated Multiscale Modeling for Design of Robust 3D Solid-State Lithium Batteries (LLNL) 1080

II.7.H. 3D Printing of All-Solid-State Lithium Batteries (LLNL) 1085

II.7.I. Advanced Polymer Materials for Batteries (Stanford University) 1092

II.8. Beyond Lithium-Ion R&D: Solid-State Batteries 1100

II.8.A. Solid-State Inorganic Nanofiber Network-Polymer Composite Electrolytes for Lithium Batteries (WVU) 1100

II.8.B. Improving the Stability of Lithium-Metal Anodes and Inorganic-Organic Solid Electrolytes (LBNL) 1104

II.8.C. U.S.-German Cooperation on Energy Storage: Lithium-Solid-Electrolyte Interfaces (ORNL) 1115

II.8.D. Lithium Thiophosphate-Based Solid Electrolytes and Cathodes for All-Solid-State Batteries (ORNL) 1121

II.8.E. Advancing Solid-State Interfaces in Lithium-Ion Batteries (ANL) 1129

II.8.F. Self-Forming Thin Interphases and Electrodes Enabling 3-D Structures High Energy Density Batteries (Rutgers, The State University of New Jersey) 1136

II.8.G. U.S.-German Co-operation: Lillint (ANL) 1145

II.8.H. U.S.-German Co-operation: CatSE (ANL) 1150

II.8.I. Dual Function Solid State Battery with Self-forming Self-healing Electrolyte and Separator (Stony Brook University) 1153

II.9. Beyond Lithium-Ion R&D: Lithium Sulfur Batteries 1159

II.9.A. Novel Chemistry: Lithium-Selenium and Selenium-Sulfur Couple (ANL) 1159

II.9.B. Development of High Energy Lithium-Sulfur Batteries (PNNL) 1166

II.9.C. Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries (Stanford University) 1173

II.9.D. Mechanistic Investigation for the Rechargeable Li-Sulfur Batteries (University of Wisconsin) 1183

II.9.E. Electrochemically Stable High Energy Density Lithium Sulfur Batteries (University of Pittsburgh) 1191

II.9.F. New electrolyte binder for Lithium sulfur battery (LBNL) 1199

II.9.G. Multifunctional, Self-Healing Polyelectrolyte Gels for Sulfur Cathodes in Li-S Batteries (University of Washington) 1204

II.10. Beyond Li-ion R&D: Lithium-Air Batteries 1220

II.10.A. Rechargeable Lithium-Air Batteries (PNNL) 1220

II.10.B. Li-Air Batteries (ANL) 1226

II.10.C. Lithium Oxygen Battery Design and Predictions (ANL) 1232

II.11. Beyond Lithium-Ion R&D: Sodium-Ion Batteries 1238

II.11.A. Exploratory Studies of Novel Sodium-Ion Battery Systems (BNL) 1238

II.11.B. Development of Advanced High-energy and Long-life Sodium-ion Battery (ANL) 1245

II.11.C. High Capacity, Low Voltage Titanate Anodes for Sodium Ion Batteries (LBNL) 1252

II.11.D. Electrolytes and Interfaces for Stable High-Energy Sodium-ion Batteries (PNNL) 1258

II.12. Beyond Lithium-Ion R&D: Battery500 1263

II.12.A. Battery500 Innovation Center (PNNL, SLAC) 1263

II.12.B. Battery 500 Seedling: Composite Cathode Architecture for Solid-State Batteries (LBNL) 1298

II.12.C. Battery500 Seedling Projects 1304

Table ES-1. Subset of EV Requirements for Batteries and Cells 18

Table 1. Subset of Requirements for Advanced High-Performance EV Batteries and Cells. (Cost and Low Temperature Performance are Critical Requirements) 104

Table 2. Subset of Targets for 12V Start/Stop Micro-hybrid Batteries (Cost and Cold Cranking are Critical Requirements) 105

Table 3. Lithium-ion battery recycling prize Phase I contest winners 110

Table I.1.A.1. Characteristics of the Annual Cell Deliverables in the Program 124

Table I.1.A.2. Phase 3 Deliverable Cell Initial Performance 126

Table I.1.A.3. Phase 3 Deliverable Abuse Tolerance Results 128

Table I.1.B.1. Gen1 Cell Builds with the Down Selected Chemistry 131

Table I.1.D.1. Overview of Program Hardware Deliverables and Build Strategy 142

Table I.1.D.2. Material Properties Comparison of NMC111 Recovered from Electrode Scrap with Pristine NMC111 from the Same Lot 143

Table I.1.D.3. Material Properties Comparison of Graphite Recovered from Electrode Scrap with the Same Type of Pristine Graphite 143

Table I.1.D.4. Cell Build 1 Test Article Characteristics 144

Table I.1.D.5. Material Properties Comparison of Direct-recycled NMC111 Recovered from Whole Cells with Pristine NMC111 148

Table I.1.D.6. Material Properties Comparison of Graphite Recovered from Whole Cells with the Same Type of Pristine Graphite 148

Table I.1.F.1. PHEV-20-mile Target Comparison 160

Table I.1.H.1. Formulation Details of Final Target Anodes 171

Table I.1.H.2. Physical Parameters of 1st and Final Target Anode Coating 171

Table I.1.H.3. Details of Anode Coatings for Single Layer Pouch Cells 172

Table I.1.H.4. Formulation and Coating Details of Anode E Coated at UMEI 172

Table I.2.A.1. 3rd Party Confirmation of High FCE 176

Table I.2.A.2. 3rd Party Confirmation of High FCE (Graphite Blend) 177

Table I.2.C.1. Summary of the High Speed Curing Experimental Runs at Ebeam Technologies 187

Table I.2.C.2. Summary of the High Speed Curing (A-dosimeter under NMC622 Coating, B-dosimeter under NMC811 Coating) 188

Table I.2.K.1. Elastic Moduli of Al-doped LLZO 235

Table I.2.K.2. Calculated Amorphization Energy of AlxLi7-₃xLa₃Zr₂O12 236

Table I.2.K.3. Calculated Surface Energy of La-terminated (011) Surface of Al-doped LLZO 237

Table I.2.M.1. Impact of Sintering Atmosphere on Density and Conductivity 242

Table I.2.O.1. Amounts of Reaction of Various Well-researched Li-ion Battery Materials 252

Table I.2.O.2/Table I.2.O.3. Most Common Precursors and Occurrence Frequencies for NMC Cathodes 252

Table I.2.Q.1. Calculations for Device Volume Inside EV Type 30 Ah Pouch Cell 266

Table I.2.R.1. Electrode Dimensions and Loadings for 1 Ah Cells 272

Table I.2.R.2. Energy Density Comparison Between CoEx Cathodes and Baseline Cathodes 273

Table I.2.R.3. Capacity of Large Pouch Cells at Varying Discharge Rates 274

Table I.2.R.4. Energy Density Improvement of CoEx Over Baseline in Large Format Cells 275

Table I.3.D.1. Impact test conditions for pouch and prismatic cells 301

Table I.3.D.2. Quasi-static test conditions for pouch and prismatic cells 301

Table I.3.D.3. Material parameters for active materials for material models MAT_025 and MAT_145 302

Table I.3.E.1. EPMA Quantitative Analysis: Average Normalized Mass% of 10 Spots Measured on Used and Pristine Cu Current Collectors 308

Table I.3.E.2. Charging Times and Efficiency with C-Rate 310

Table I.4.A.1. Challenges for Li-Ion Battery Recycling 316

Table I.4.C.1. Modeling and Analysis Focus Area Major Efforts in Q3 FY2019 330

Table I.4.C.2. GDOES-determined Lithium Content as a Function of Lithia Source at 500℃ 332

Table I.4.C.3. GDOES-determined Lithium Content as a Function of Lithia Source at 650℃ 332

Table I.4.C.4. Comparison of Relithiation, Delithiation and Reversible Capacities for Half Cells Relithiated at Room Temperature or 50℃ 334

Table I.4.C.5. Summary of Large Scale Ionothermal Experiments, TGA, ICP, and XRD Results 335

Table I.4.C.6. ICP-OES Results 337

Table I.4.C.7. Cycle Performance 338

Table I.4.C.8. Result of NMC111/LMO Separation via Froth Flotation Using Collector A 350

Table I.4.C.9. Result of NMC111/LCO separation via froth flotation using collector A 350

Table I.4.C.10. Result of NMC111/LMO Separation via Froth Flotation Using Collector B 351

Table I.4.C.11. Result of NMC111/LMO Separation via Froth Flotation with Collector A in Flotation Column 351

Table I.4.C.12. ICP Analysis of Black Mass used for Impurity Discovery 352

Table I.4.C.13. Element Ratios Measured Using GDOES 356

Table I.4.C.14. Electrode Information 364

Table I.4.C.15. Preliminary Estimate of Rejuvenation Hardware on Pack Energy Density from BatPaC 368

Table I.4.C.16. CAMP Cells to be Used for Thermal Characterization (Cathode Material supplied by Toda and Anode Material by Superior Graphite) 370

Table I.4.C.17. Progress of EverBatt Customization in Q4 FY2019 373

Table I.4.C.18. Sample Information: XPS/SEM Study 381

Table I.5.B.1. Conductivity of Different New Electrolyte Blends to Enable Fast Charge 396

Table I.5.C.1. Heat Efficiency and Heat Rate for Fast Charge Algorithms 407

Table I.5.E.1. Cycling Profile for Baseline COTS and UM Cells 418

Table I.5.E.2. Cells used to esablish baseline lithium plating performance 418

Table I.5.G.1. Normalized Lithium Plating Capacities for Fully Lithiated Electrodes Subjected to Voltage Holds of -10 mV, -15 mV and -20 mV for 6 hours 433

Table I.5.G.2. Normalized Li(110)/Cu(220) Peak Area Ratios from XRD Measurements of Electrodes Recovered from Half Cells Subjected to Voltage Holds of -10 mV, -15 mV and -20 mV for 6 hours 433

Table I.6.A.1. Cost Data for Extreme Demand Scenario 475

Table I.6.A.2. Cost Data for Seasonal Demand Scenario 476

Table I.6.A.3. Design Considerations for Cost and Thermal Model of an EVSE 478

Table I.6.A.4. EVSE Component-wise Cost Estimate for a 1-MW, 13.8-kV Setup 480

Table I.6.A.5. EVSE PE Total Cost Estimate for a 1-MW, 13.8-kV Setup 480

Table I.6.A.6. Pack Estimation Calculation Table (Shaded Row Represents the C/2 Discharge Rate) 484

Table I.6.A.7. Degradation Mechanism Models 489

Table I.6.A.8. Acceleration Factors Used for Building Degradation Rate Laws 489

Table I.6.A.9. Heat of Fusion and Transition Temperature for Several PCM Composites with Varying Mass Fraction of PCM 495

Table I.7.A.1. Input Values and Results from BatPaC 3.1 for a 94 kWh Battery Pack for a Battery Electric Vehicle (BEV) 506

Table I.7.B.1. Status of Deliverables for Testing 510

Table I.7.E.1. Capacity Values for Cathodes Made in MERF 527

Table I.7.E.2. Delithiation Capacity and Voltage for Cathodes Made in MERF 530

Table I.7.E.3. Ceramic Materials Under Test as Coatings on Anode 532

Table I.7.E.4. Oxofluorophosphate and HF Yields after 1 Week of Aging in Electrolyte with 8,300 ppm Water 539

Table I.7.E.5. Summary of Electrode Library Distributions 541

Table I.7.F.1. Electrode Composition and Physical Properties 544

Table I.7.G.1. Articles Tested for USABC 552

Table I.7.G.2. Articles Tested for Benchmark 552

Table II.1.A.1. Summary of Grafting Density, Loading Density, Initial Capacity, Coulombic Efficiency, Capacity Retention, and Charge-transfer Resistance (Rct) of Graphite/silicon Composite... 584

Table II.1.A.2. Si Powder Description 589

Table II.1.A.3. Electrodes with Silicon, Graphite (Gr), Carbon Black (CB) and LiPAA 590

Table II.1.A.4. Surface Compositions of the Electrode Samples Measured by XPS 590

Table II.1.A.5. First Cycle Capacities and Coulombic Efficiencies of Half Cells with Si Electrodes 592

Table II.1.A.6. Discharge Capacities (1st and 99th cycle) and Capacity Retention of the Full Cells 595

Table II.1.A.7. Formulations and Notations of the Electrolytes Used in this Study 596

Table II.1.A.8. Proposed Compounds from HPLC Data 607

Table II.1.B.1. Quantified Energy Generation Based on the Fit Curve of the Paraclete-4KD + CB Sample as well as predicted material and performance loss based on the formation of silica 636

Table II.1.B.2. Copper-based Substrates Investigated With Protocol 1 648

Table II.1.B.3. Summary of the Investigated Effects on the Passivating Properties of Silicon and Preliminary Conclusions 650

Table II.1.B.4. Summary of Results: SSRM 3D Resistivity vs. Depth Profiling of SEI and AFM Roughness 665

Table II.1.B.5. Raman Peak Assignments 687

Table II.1.D.1. Electrochemical Performance of NMC532 || Si/Gr (CAMP Electrodes) Full Cells in BTFE- based Electrolytes with Different Salt Concentrations 718

Table II.1.D.2. Swelling of Si/Gr Anode in Different Electrolytes 719

Table II.1.D.3. Molarity, Viscosities and Self-extinguish Time (SET) of Three Baseline Electrolytes and Two Localized High Concentration Electrolytes 720

Table II.1.E.1. Electrochemical Performance of Si Anode after being Preliathiated under Different Conditions 726

Table II.2.A.1. DSC Samples with Various Amounts of Active Material and Electrolyte 739

Table II.2.A.2. Twelve Most Intense Ions Detected via HPLC and Corresponding Chemical Structures 741

Table II.2.A.3. FTIR Peak Assignments for Gen2 Electrolyte 744

Table II.2.B.1. Rietveld Refinement and Particle Size Analysis Results of LiNi0.94Co0.06O₂ 757

Table II.2.B.2. Summary of Electrochemical Properties of Ni94Co6 757

Table II.2.B.3. Rietveld Refinement Analysis of Samples 760

Table II.2.B.4. Model Systems Prepared with Various Synthesis Conditions for NMR Studies 766

Table II.2.D.1. Theoretical and Experimental Properties of LT-LiCo1-xAlxO₂ Electrodes for 0 ≤ x ≤ 0.5 785

Table II.3.E.1. Summary of Physical Properties, Ionic Conductivity and Li+ Transference Number o fPMpipFSI with Different LiFSI Concentrations 843

Table II.3.G.1. 200 mAh Cell Thickness Changes Following 200 Charge/discharge Cycles at .7C 860

Table II.4.A.1. Project performance targets for cathode active material and cell made with this material 866

Table II.4.A.2. Summary of Samples and Precursors Used to Synthesize NCM811 869

Table II.4.C.1. Equilibrium Reactions, Solubility Product Constant and pH of Precipitation 887

Table II.4.E.1. Performance Targets 902

Table II.4.F.1. Rietveld Analysis of LNMTO Cathode Powders 910

Table II.4.G.1. I(003)/I(104) Values of the LiNi0.83Co0.11Mn0.06O₂ Materials Synthesized at Various Temperatures 916

Table II.4.G.2. C/3 Capacity of the Cells Measured at Room Temperature 918

Table II.6.G.1. Comparison of the Intrinsic Material Properties of Different Solid Electrolytes 1029

Table II.7.G.1. Calculated elastic constants for Li metal, cubic LLZO and hexagonal LiCoO₂ 1081

Table II.7.G.2. Calculated strain-depedent activation energy of Li-hopping in LiCoO₂ 1081

Table II.7.G.3. Effects of vacancy on the activation energy of Li-ion diffusion in cubic LLZO 1082

Table II.7.H.1. Development of Ink Recipes for 3D Printing 1089

Table II.8.D.1. Chemically Titrated Capacities of LiPS 3 and LiPS 3ㆍS cathode powders 1127

Table II.8.G.1. Coordination Ratio α and the Ratio of Diffusion Coefficients of Toluene, VC and EMC Before and After the Addition of LiPF6 1147

Table II.8.G.2. Coordination Ratio α and the Ratio of Diffusion Coefficients of Toluene, VEC and EMC Before and After the Addition of LiPF6 1147

Table II.8.I.1. Quarterly Milestones and Verification for FY19 1154

Table II.9.D.1. Test results of ten synthesized co-polymer electrodes in 2018, but with improved electrode processes 1186

Table II.9.E.1. Battery Specifications for the Battery 500 Program 1192

Table II.9.G.1. Breakdown of SIG/S/C slurry (and subsequent cathode) composition by weight. The demonstration cell formula was used for QSS cells with ~1 mgS/cm2 cathode loading,... 1211

Figure ES-1. Estimated costs of cells in automotive battery packs with different combination of electrodes. The packs are rated for 100 kWhTotal (85 kWhUseable), 300 kW, 315 V, 168 cells,... 20

Figure ES-2. 2019 Nobel Laureate battery researchers partially funded by VTO 23

Figure ES-3. Cell capacity (blue) and the energy (red) of a 2.5 Ah pouch cell as a function of cycling. The cell energy was measured based on the weight of the whole pouch cell including... 24

Figure 1. Chemistry classes, status, and R&D needs 106

Figure 2. Potential for Future Battery Technology Cost Reductions 106

Figure 3. Battery R&D Program Structure 108

Figure 4. The whole cell capacity (blue) and the specific energy (red) of a 2.0 Ah pouch cell as a function of charge and discharge cycles. More than 90% of the cell capacity and specific... 111

Figure 5. (a) EverBatt's flowsheet, (b) Example breakdown of a lithium-ion battery recycling cost, including transportation, and (c) Chart comparing battery manufacturing cost and environmental... 112

Figure 6. Effect of using mixed-salt electrolytes on 7mAh full cells in xx3450 single layer pouch cell format assembled versus LMR-NMC with 80% Si nanoparticles, 10% hard carbon and... 113

Figure 7. (a) First discharge curve of S5Se2/C cathode in DME-based electrolyte and TTE-based electrolyte; (b) In-situ Se K-edge XANES spectra of S5Se2/C cathode in TTE-based electrolytes... 114

Figure 8. Rate performance and d) cycling performance at high rates of S22.2Se/KB cathode and S/KB cathode in TTE-based electrolyte 114

Figure 9. Schematic illustration of the approach for rational synthesis of high-Ni layered oxides with a "closed" loop, specifically, through studying the surface reconstruction, its impact to... 115

Figure 10. (a) Rate performance and (b) impedance of the LiNi0.7Mn0.15Co0.15O₂ samples by slow cooling and quenching 115

Figure 11. Key parameters which need to be controlled during the technology development and evaluation process. From Chen et. al, Joule 3, 1-12, 2019 116

Figure 12. Universal test fixture designed to enhance data fidelity and repeatability while also providing advanced safety features 117

Figure 13. The SEM micrographs of secondary cathode particles (~10μm diameter) show the extent of interprimary particle separation (cracking) at fresh (no fast charge cycling) and the end... 118

Figure 14. a) X-ray diffraction spectra of PVdF films produced by drying NMP-based slurries at different temperatures. b) log-log plot of room temperature conductivity data versus inverse... 118

Figure 15. Resistance versus DOD for electrodes dried at different temperatures a) active material and carbon black mixed together first; b) carbon black and polymer slurry mixed together first 119

Figure 16. (a) Optical image of cathode infiltrated LLZO bilayer. Cathode infiltrated porous layer surface (left) and dense layer surface (right) are shown. (b) SEM fracture surface image of... 119

Figure 17. (a) Representative HAADF-STEM image of Li1.2Ni0.4Ru0.4O₂, showing the layered-rocksalt intergrown structure along the [110] zone axis; (b) charge-discharge voltage profiles... 120

Figure 18. (a) The relative surface oxygen release energies of doped LiNiO₂ with respect to the pristine phase. Yellow-orange color indicates an improved oxygen retention, while the purple... 121

Figure 19. (A) NFA cathode particles synthesized through a co-precipitation reaction in a CSTR and (B) Charge/Discharge curves indicating the good capacity and performance delivered by... 122

Figure I.1.A.1. 18-layer densified NMC811 and un-densified graphite containing cell (52.6Ah) dimensions 125

Figure I.1.A.2. Program final deliverable cells weight, thickness and capacity @ C/3 discharge rate and 30° 126

Figure I.1.A.3. Program final deliverable cells full HPPC performance at 30℃ 127

Figure I.1.B.1. a DST Cycle life for Gen1 Cells 1b) Cycle life data@ different pressure 131

Figure I.1.B.2. a) Calendar life capacity retention for the Gen 1 deliverable chemistry & b) DCIR 132

Figure I.1.B.3. a and b Capacity retention and capacity for the double layer pouch cells targeting~300- 310Wh/Kg in the 77-80Ah cell form factor 132

Figure I.1.B.4. Shows the initial result for the silicon materials with cathode for a fixed capacity of 4.35mAh/cm² 133

Figure I.1.B.5. Shows the initial result for high efficiency anode with Gen1 cathode in double layer pouch cell 133

Figure I.1.C.1. Si anode failure mechanisms (left), NanoGraf graphene-wrapped silicon anode architecture (right) 135

Figure I.1.C.2. Normalized full cell capacity versus cycles for pure NanoGraf anodes with NMC523 cathdoes 136

Figure I.1.C.3. Normalized full cell capacity versus cycles for assorted electrolyte compositions 137

Figure I.1.C.4. NanoGraf anode coating on pilot-scale equipment with 4mAh/cm2 and 10wt% binder content 138

Figure I.1.C.5. NanoGraf materials production quantities through FY19 (top) and improved consistencey between batches and production scales (bottom) 139

Figure I.1.D.1. Pictorial representation of the direct recycling process which largely relies on physical separation processes; compared to other recycling technologies, the positive electrode... 141

Figure I.1.D.2. Electrode scrap direct recycling process overview. First manufacturing residues such as off-spec coated electrodes and dried out slurry residue are milled to produce coarse... 143

Figure I.1.D.3. Distribution of cells between test facilities (ANL = Argonne National Laboratory; FEI = Farasis Energy USA) and conditions (DST = Dynamic Stress Test; "1C disch." = constant... 144

Figure I.1.D.4. Normalized C/3 static capacity test results from RPT0 and RPT1 for all cells. A0 = pristine graphite, A1 = recycled graphite, C0 = pristine NCM111, C1 = recycled NCM111.... 145

Figure I.1.D.5. HPPC pulse resistance data for all cells and test conditions. Some of the data from RPT0 indicate an anomalously high resistance near mid-SOC and do not represent the normal... 146

Figure I.1.D.6. Capacity retention as a function of cycle number for cells under 1C constant current discharge test condition 147

Figure I.1.D.7. Process diagram for direct recovery of valuable materials from Li-ion cells 147

Figure I.1.E.1. Hardware Strategy of the Program 151

Figure I.1.E.2. Synthesized NMC622 with Different Magnifications 152

Figure I.1.E.3. Summary of NMC622 Coating 152

Figure I.1.E.4. Characterization of WPI and Control Powder 153

Figure I.1.E.5. Cycling Performance of Single Layer Pouch Cells, TXS10222: dry coating, TXS10227: wet coating, TXS10228: no coating, TXS10229: A123 control powder 153

Figure I.1.E.6. Cathode powder in different milling batches 154

Figure I.1.E.7. Coin Cell Testing Results for the 6kg NMC622 155

Figure I.1.F.1. High-voltage measurement schematic (left). Power electronics breakout for voltage and current measurement (right) 157

Figure I.1.F.2. OBD e-PID messages reverse engineered 157

Figure I.1.F.3. HwFET engine & motor torque during charge-sustaining operation 158

Figure I.1.F.4. HPPC results from the cell-level testing 159

Figure I.1.F.5. Cell teardown 159

Figure I.1.G.1. Projected cell development progression throughout the USABC program 163

Figure I.1.G.2. Cycling performance from 12 Ah capacity pouch cells at 1C rate (a) and 15 minute fast charge (b) conditions 163

Figure I.1.G.3. Cycling performance in coin-cell full-cells from different electrolyte formulations 164

Figure I.1.G.4. Specific capacity (a), specific energy (b) and energy density (c) at C/3 rate from CB#1 cells 165

Figure I.1.H.1. Long term cycling of pouch cells with baseline thickness, 93/3/4 and with NMC622 cycled under C/3 168

Figure I.1.H.2. Details of different UMEI trials 168

Figure I.1.H.3. Long term cycling of baseline pouch cells (NMC622 cathode at 22mg/cm² coating weight) made in June 2018 and November 2018 169

Figure I.1.H.4. Long term cycling of 1 st target cells (NMC 622 cathode at 30mg/cm² coating weight) made in November 2018 and April 2019 169

Figure I.1.H.5. a. Discharge capacity and b. Capacity retention of first target pouch cells (NMC622 cathode at 30 mg/cm² coating weight) fabricated in April 2019 170

Figure I.1.H.6. Long term cycling of pouch cells with final target thickness, 93/3/4 and with NMC622 cathodes and matching anodes, cycled under C/3 at 30℃ 171

Figure I.1.H.7. a. Discharge capacity of single layer pouch cells with final target cathode (40mg/cm²) and matching anodes with different binders. b. Capacity retention of SLPs with final... 172

Figure I.1.H.8. a. Discharge capacity and b. capacity retention of 5 Ah Multi-layer pouch cells with final target cathode (40mg/cm²) and matching anode E coated at pilot scale 173

Figure I.1.H.9. Discharge capacity of 2 Ah Multi-layer pouch cells (N/P~1.1) with final target cathode (40mg/cm²) and matching anode E with different electrolyte volume. Standard is refer... 173

Figure I.1.H.10. Comparison of discharge capacities of SLPs (0.5 Ah) and MLPs (5 Ah and 2 Ah with low electrolyte volume) 174

Figure I.2.A.1. 3rd Party data for G14's lab-pilot scale Si-C: Confirmation of high FCE 176

Figure I.2.A.2. 3rd Party data for G14's lab-pilot manufactured Si-C: 〉 800 Cycle stability 177

Figure I.2.A.3. Cost model (BatPaC 2018 v. 3) using increasing amount of Si-C in the anode 178

Figure I.2.B.1. Side-to-side coating weight comparison between Coating Conditions 1 (black) and Coating Conditions 2 (red) (left) and coating weight of NMC 622 electrodes coated on the... 181

Figure I.2.B.2. Analysis of digested cathode electrode from the 150th and 300th foot of coating (left) Coin cell half-cell performance of NMC 622 Build 2 electrodes produced on the mini-coater... 182

Figure I.2.B.3. Lab-scale film build of NMC 622 electrodes coated using Coating Conditions 2 (red) and 3 (black) (left) and coin cell half-cell performance of lab scale NMC 622 electrodes... 183

Figure I.2.B.4. Discharge capacity retention vs. cycle number of electrocoat-based cells (blue) and PVDF/NMP control (black) (left). DCR measurements of electrocoat-based cells (blue) and... 183

Figure I.2.B.5. Cycling performance for pouch cells with PPG cathodes secondary dried at 100, 120, 140, and 160℃ for 4h at ORNL R2R Manufacturing Group comparing rate capability (left) and... 184

Figure I.2.C.1. Cycling performance of 200 mAh pouch cell using NMC811 electrodes processed using two different curing conditions: 500 fpm/290kV/60kGy with 820 ppm O₂ and 400 fpm/290...///// 189

Figure I.2.C.2. Voltage-capacity curves of EB cured NMC cathodes at different rates 189

Figure I.2.C.3. Cycling performance of full coin cells with NMC cathodes using different binders 190

Figure I.2.C.4. (a) DSC curve of an EB cured resin with Tg appearing at -36.38℃. (b) full coin cell cycling performance using resin with low Tg, which shows similar cycling performance... 190

Figure I.2.D.1. a) Capacity retention comparison between NMC 811 cathodes made via NMP-processing, aqueous- processing, and NMP-processing with the NMC811 powder pre-exposed... 193

Figure I.2.D.2. Top left) Comparison of USABC 0.33C/-0.33C cycle life, and top right) rate performance between three different aqueous-processed NMC811 cathodes, and an NMP-processed... 194

Figure I.2.D.3. HPPC of full cells made with NMP-and aqueous-processed NMC811 cathodes 195

Figure I.2.D.4. Left) Comparison of 0.33C/-0.33C cycle life between three aqueous-processed NMC 811 and NMP-processed NMC811 baseline cathode cycled at 30℃ and 45℃. Right) HPPC... 195

Figure I.2.D.5. Comparison of rate performance of a thick (~7 mAh/cm²) aqueous-processed NMC 811 cathode with two thick NMP-processed NMC811 baseline cathodes in coin cell configuration 196

Figure I.2.D.6. Optical micrographs of aqueous NMC811 coatings of various thicknesses made on aluminum (left) and copper foil (right) substrates 196

Figure I.2.D.7. Optical micrographs of aqueous NMC811 coatings of various thicknesses made on copper foil substrate using carbon black (bottom) and carbon fibers (VGGT)(top) as the... 196

Figure I.2.D.8. SEM and optical microscope images of aqueous-processed cathode coatings (500 µm coating wet gap) on copper foil comprising VGGT conductive additive, and NMC811with... 197

Figure I.2.D.9. Electrolyte imbibition coefficient dependence on salt concentration (a) and porosity of NMC532 cathode (b) and A12 anode (c) 198

Figure I.2.E.1. Morphologies and XRD profile of nickel-rich compositions at different temperatures; table shows the Rietveld refinement analysis 203

Figure I.2.E.2. Voltage profile of nickel-rich compositions with different lithium ratios at different temperatures. Bottom row shows rate capabilities (3.0-4.3 V cycling at 30℃; 1C = 200 mA/g) 204

Figure I.2.E.3. DSC profiles of some of the nickel-rich compositions compared to commercially available NMC532 and NMC811 chemistries 204

Figure I.2.E.4. Scaled-up NCM811 ~7 µm particles at 1-kg scale in support of "Thick, Low-Cost, High-Power Lithium-Ion Electrodes via Aqueous Processing (BAT164)" 205

Figure I.2.E.5. Chemistries for advanced particle coatings: ~4-5 µm NCM622, NCM811, and LNO particles, Volexion Inc. (Image Credit: Jung Woo Seo, Volexion) 205

Figure I.2.E.6. Morphology of single-crystal NMC cathodes; former precursors were made by using a 1-L TVR 206

Figure I.2.F.1. In situ electrochemical testing of LLZO+NMC622 composite cathode showing compatibility of the LLZO and NMC622 phases 208

Figure I.2.F.2. The cycle life of NCM622 (left) and NCM811 (right) fabricated by FSP powders 209

Figure I.2.F.3. (a) In situ Raman spectrometer and (b) Flame emission spectroscopy sample data from the multi-fiber probe array of FSP flame in the OH region 210

Figure I.2.G.1. Installed supercritical fluids system for processing battery cathode materials 212

Figure I.2.G.2. Optimization of synthesis variables to achieve final target properties of battery materials 212

Figure I.2.G.3. Preliminary synthesized NMC811 precursor using sulfate starting materials 213

Figure I.2.G.4. Preliminary synthesized NMC811 precursor using acetate starting materials 213

Figure I.2.G.5. Synthesized NMC811 precursors with various particle sizes and morphologies using acetate starting materials 213

Figure I.2.G.6. Three-dimensional reconstructed image and element percentage plot of the synthesized single-crystal-like NMC811 precursor 214

Figure I.2.G.7. Two-dimensional concentration distribution image of the synthesized single-crystal-like NMC811 precursor 214

Figure I.2.G.8. Preliminary coin cell result of 1-μm NMC811 using supercritical fluids synthesis process 215

Figure I.2.H.1. SEM image of NCA powders after annealing at 800℃ 217

Figure I.2.H.2. Charge-discharge of the NCA powders and cycling performances at 1C 217

Figure I.2.H.3. Charge-discharge of NCA powder made from the flame spray process with further improved capacity 218

Figure I.2.H.4. Cycling performances of the NCA powders at 1C and 5C, showing extraordinary retention rates 218

Figure I.2.H.5. Charge-discharge of NMC811 powder made from the flame spray process at 0.1C 219

Figure I.2.H.6. NMC811 cycling performances at 1C 219

Figure I.2.H.7. Effect of NMC cathode material components on (a) MCSP and (b) cost of cells 220

Figure I.2.I.1. (a) As-spun Si/PAA-C/PAI mat (20% C, 45% Si, 35% binder (3% PAI, 32% PAA); scale bar = 2µm, (b) Cross section of Si/PAA-C/PAI compacted and welded mat; scale bar... 224

Figure I.2.I.2. (a) SEM image of an as-spun Si/PAA-C/PVDF raw mat, composition: 20% C, 45% Si, 35% binder (3% PVDF, 32% PAA) scale bar = 2µm, (b) Cycling performance of the Si/PAA... 224

Figure I.2.I.3. SEM images of (a) Raw electrospun Si/PAA (40 wt.% PAA) fiber mat, (b) Final electrode obtained after mat densification; magnification 3,000x, and (c) Cycling performance... 225

Figure I.2.J.1. Reaction to produce F-DEC 228

Figure I.2.J.2. Reaction to produce F-EMC 228

Figure I.2.J.3. Catalyst screen results and reaction calorimetry for flow condition of F-EMC 229

Figure I.2.J.4. Corning flow reactor and close up of the dual plate system for the synthesis of F-EMC 229

Figure I.2.J.5. Catalyst screen results and NMR study showing selective catalyst activity 230

Figure I.2.J.6. Proposed flow chemistry process for TFPC 230

Figure I.2.J.7. Catalyst activity and solvent screen for TFPC 230

Figure I.2.J.8. Full scale reaction conversion results 231

Figure I.2.J.9. Synthesis of salt-free Ionic Liquids 231

Figure I.2.K.1. Optimized amorphous(top) and crystalline(bottom) structures of Al x Li 7-3x La 3 Zr 2 O 12 236

Figure I.2.K.2. Optimized surface structures of Al doped cubic LLZO. Only Li (green) and Al (grey) are shown as spheres, the La-O and Zr-O bonds are shown as sticks. ΔE represents the energy... 237

Figure I.2.M.1. Impact of sintering atmosphere on phase purity and sintering behavior. (Left) XRD patterns and (right) derivative of dilatometry shrinkage curves 242

Figure I.2.M.2. Optimization of Li loading and sintering parameters. (Left) Density and conductivity of LLZO pellets sintered for various hold times at 1075℃ with 3wt% Li₂CO₃. (Right) Overview... 243

Figure I.2.M.3. (Left) Tapecasting dispersant optimization and (right) photograph of optimized LLZO tape 243

Figure I.2.N.1/Figure I.2.N.2. The resistance of laminates dried at different temperatures as measured by applying a current pulse for 30 seconds and measuring the change in voltage divided by the change... 246

Figure I.2.N.2/Figure I.2.N.1. The adhesion and cohesion of laminates of cathode material dried at different temperatures from 80 to 190℃ 246

Figure I.2.N.3. The spectroscopic results of x-rays taken of films prepared with different levels of carbon black dried at different temperatures. The ratio of PVdF to carbon black is indicated... 247

Figure I.2.N.4. The film on the top was formed from the Solids process and dried at 170℃; the film on the bottom was formed from the Glue process and dried at 180℃. The film on the left... 248

Figure I.2.N.5. Resistance of the electrodes dried at different temperatures versus depth of discharge for 30 second discharge pulses 248

Figure I.2.N.6. SEM of electrode surface 248

Figure I.2.O.1. Sintering temperature versus fraction of Ni in M content for various NMC cathode materials found in our solid-state synthesis dataset. As shown by the plateaus, high Ni content... 253

Figure I.2.O.2. K-means clustering of synthesis products in our database with the developed features. Materials with different chemistry are clustered into different groups in the feature space 253

Figure I.2.P.1. (a) During coprecipitation of NMC352 carbonates, the residual amounts of metal cations within the reacting solution at different values of pH are shown. (b) Comparison between... 256

Figure I.2.P.2. (a) SEM image of precipitated MnCO₃ particles obtained with 1.5mM concentration of Mn2+. (b) SEM image of precipitated MnCO₃ particles obtained with 4.5mM concentration... 257

Figure I.2.P.3. As the free energy for the (102) surface decreases, the equilibrium shape converts from a hexagonal unit cell to a rhombohedral particle. The surface energy of the rhombohedral... 258

Figure I.2.P.4. (a) Cubic shape of the MnCO₃ particles can be obtained with (103) facets. (b) At higher concentrations of Mn2+, the (103) facets demonstrate lower surface energy as... 258

Figure I.2.P.5. (a-b) Phase field variables indicating the shape of the MnCO₃ particles obtained at 1.5mM and 3.0mM concentrations. It is evident that the aspect ratio decreases from 1.26 to... 259

Figure I.2.P.6. Growth of particle size with time as observed for the initial metal concentration of 4.5mM. The growth rate is also denoted by the red circles, which clearly indicates that at longer... 259

Figure I.2.P.7. (a) Evolution in size of the LZO precursors with increasing temperature. These LZO particles convert to cubic- LLZO. (b) Formation of LLZO and increase in their particle size is... 260

Figure I.2.P.8. Comparison between the experimental (blue diamond) and computational (black solid line) results for particle growth observed in LLZO during the formation step of synthesis.... 261

Figure I.2.P.9. Comparison of densification observed in small, large and bimodal shaped LLZO particle. It is evident that bimodal particles experience the maximum amount of increase in relative... 261

Figure I.2.Q.1. Cycling of 400 mAh Si pouch cells at C/3 and room temperature with and without continuous relithiation using L3B passive control. (Left) Number of cycles to 80% remaining... 265

Figure I.2.Q.2. Demonstration of estimation algorithm with 10% initial error in positive electrode capacity (left) and lithiation extent (right) 267

Figure I.2.Q.3. Real time estimation framework for individual electrode algorithm developed by UCD 267

Figure I.2.Q.4. Demonstration of prelithiation for 15 wt% Si pouch cells. Yellow and Blue lines represent capacity during C/3 cycling for cells with 15% prelithiation done over 1 week using... 268

Figure I.2.Q.5. Moles of lithium versus distance from lithium reservoir predicted from 2D transport model for prelithiation over different lengths of time. The moles of lithium is relative to number... 268

Figure I.2.R.1. 3-D Microscope images of as-printed and dried (a) and post-calendered (b) cathode electrodes produced via CoEx. Images illustrate the corrugated topography that persists after... 271

Figure I.2.R.2. Electrochemical Performance of 1 Ah pouch cells, comparing thin and thick baselines vs. CoEx cathodes. Error bars represent +/- 1 standard deviation. Quadratic curve fits are... 273

Figure I.2.R.3. Normalized capacity of large format pouch cells at discharge rates from D/10 to 7.5D, comparing thin and thick baselines vs. CoEx cathodes. Data points are median values,... 274

Figure I.3.A.1. Effect of aging on mechanical properties of anode versus the cathode: the moduli were dominated by that of the current collector material and there was noticeable difference... 278

Figure I.3.A.2. (Top) Microstructure model 3D computational domain. (Bottom) Schematic of static scaling numerical test applied in the paper [18] using high-performance computing 279

Figure I.3.A.3. (a) Silicon/NMC cell voltage variation during 1C charging and (b) porosity distribution within the electrode at the end of C/50 charge with and without large deformation and... 280

Figure I.3.A.4. (a) EBSD mapping of NMC polycrystalline architecture. (b) Discontinuous and continuous damage models, respectively resolving and homogenizing polycrystalline architecture 281

Figure I.3.A.5. Schematic of 1D Li-sulfur model and polysulfide reaction sequence 281

Figure I.3.B.1. Workflow for converting 3D imaging to simulation including the conductive binder domain 286

Figure I.3.B.2. Planar snapshots from a full 3D mesostructure under 5C constant current discharge. In all cases, the current collector is at the top of the image, with the separator at the bottom.... 287

Figure I.3.B.3. Electrolyte phase tortuosity for both in-plane (top) and out-of-plane (bottom) directions. Markers represent mean values across simulated subdomains while error bars represent... 288

Figure I.3.B.4. Simulation methodology: (I) The manufacturing of three- phase electrodes, from slurry drying to calendering, is simulated using granular and colloidal dynamics. The AM particles... 288

Figure I.3.C.1. (a) Relaxation dynamics for cell voltage U at different C-rates. The constant-current charging was terminated when U reached 4.39 V. The solid lines are least squares fits to eq.... 293

Figure I.3.C.2. Extrapolated voltages U for relaxation kinetics of cell-I shown in Figure I.3.C.1 and plotted vs. C-rate during charge. Traces i, ii, and iii correspond to the voltage before and... 293

Figure I.3.C.3. Relaxation dynamics of the (a) anode and (b) cathode potentials for voltage-limited charging of cell I shown in Figure I.3.C.1 and Figure I.3.C.2. The C-rates are color coded as... 294

Figure I.3.C.4. (a) Voltage changes induced by τ=10 s pulses applied at 4.2 V. The C-rates during the pulse are given in the inset. (b) The initial (open circles) and end-of-pulse (filled circles)... 295

Figure I.3.C.5. Relaxation kinetics for U after a 10 s long charge pulse applied at 4.2 V (solid lines). The dashed lines are least squares fits to eq. 1. (b) A plot of time constants for the fast (τf)... 295

Figure I.3.D.1. Project schematic showing major constituents and progression of Alpha and Beta versions 297

Figure I.3.D.2. Model setup for a pouch cell impacted by (a, b, c) a semi-sphere and (d, e, f) a semi-cylinder indenter, where the cell bulk is represented by (a, d) standard solid elements,... 299

Figure I.3.D.3. Comparison of (a) loading force, (b) cell voltage and (c) state of charge in models with different indenters and element types 299

Figure I.3.D.4. Temperature distribution in (a, d) solid element model, (b, e) composite tshell model and (c, f) macro model when a pouch cell is impacted by a (a, b, c) semi-sphere and... 300

Figure I.3.D.5. Comparison of the relative computational time in different models 300

Figure I.3.D.6. Layered element model for (a) spherical and (b) cylindrical indentation 303

Figure I.3.D.7. Indentation loads obtained by different active material model formulations and comparison with experiments for (a) spherical and (b) cylindrical indentation 303

Figure I.3.D.8. Shear test. (a) experimental setup, and (b) simulation model 304

Figure I.3.D.9. Load displacement curve for the shear test. Label "Shear phase" denotes the reacting force on the supports to the shear loading step 304

Figure I.3.E.1. Fragmentation of copper current collectors observed by 3D XCT in a small prismatic cell (a), (b) and (c), and the top cell of large format LG-Chem 10-cell stack (d), (e) and... 307

Figure I.3.E.2. (a) EPMA element maps of a used anode and (b) line profiles of four elements across one interface, (c) STEM image and element mapping, and (d) Line profiles of four elements... 308

Figure I.3.E.3. Comparison of charge and discharge voltages with the experiments 309

Figure I.3.E.4. Lithium ion concentration through thickness of the cell during charge cycle at 5C rate 310

Figure I.3.E.5. Discharge voltage (left) and temperature (right) profiles for a battery cell at 1C, 2C, and 3C discharge rates. Experiment data shown as dotted lines and model results as... 311

Figure I.3.E.6. Voltage (left) and temperature (right) profiles for cells in a battery pack under constant discharge conditions. Each line represents a single battery cell in the pack 311

Figure I.3.E.7. EOL cycle and SOH decay rate as a function of C-rate and temperature 312

Figure I.3.E.8. Normalized battery capacity compared to number of cycles at different temperatures 312

Figure I.4.A.1. Supply from recycling depends on demand growth 315

Figure I.4.A.2. Need for upcycling of recovered material 316

Figure I.4.B.1. Materials Research Plan with three major areas of research to address critical materials issues for lithium-ion batteries and recovery of materials for reintroduction into... 319

Figure I.4.B.2. Left: Logo of the Lithium-Ion Battery Recycling Prize. Right: The Lithium-Ion Battery Recycling Prize consists of three progressive phases from concept through pilot validation,... 320

Figure I.4.B.3. There are five main areas of interest within Phase I of the prize to help address the various issues that arise in the battery recycling supply chain 321

Figure I.4.B.4. The 15 Phase I winning teams submitted innovative proposals from across the United States 324

Figure I.4.B.5. Assistant Secretary Daniel Simmons announced the 15 winners of Phase I at NREL on September 25, 2019 324

Figure I.4.C.1. ReCell organization chart as of the end of FY19Q2 327

Figure I.4.C.2. ReCell Pilot Scale High-bay located at Argonne National Laboratory Building 369 328

Figure I.4.C.3. ReCell Laboratory off the High-bay 328

Figure I.4.C.4. XRD patterns of Relithiated NMC versus starting lithia source 331

Figure I.4.C.5. Rate performance of LiOHㆍH₂O relithiated NMC (650℃) half-cell 333

Figure I.4.C.6. (a) and (b) XRD patterns for pristine NMC111, chemically delithiated NMC111, and relithiated NMC111 (reaction condition: LiCl, [C2OHmim][NTf2], 150℃, 24 h). (c) and (d)... 335

Figure I.4.C.7. Comparison of TGA plots of black powder from (a) LiBr-in three different ionic liquids and (b) three large scale experiments with pristine and delithiated NMC111 336

Figure I.4.C.8. 1st and 2nd charge-discharge curves for the pristine, delithiated, and relithiated samples before (a) (b) and after calcination at 500℃ (c) (d) 337

Figure I.4.C.9. (a) 2nd charge-discharge curves and (b) cycle performance for the pristine, delithiated, and relithiated samples 338

Figure I.4.C.10. High resolution XPS spectra of T-NCM111 (a), D-NCNM111 (b), HT-220C-1h-NCM111(c) and HT-220C-2h-NCM111 (d) 340

Figure I.4.C.11. High resolution XPS spectra of HT-160C-1h-NCM111(a), HT-160C-2h-NCM111 (b) and HT-160C-4h-NCM111 (c) 340

Figure I.4.C.12. Cycling stability of D-NCM111 after hydrothermal lithiation at 220C (a) and 160C (b) for different time 341

Figure I.4.C.13. Cycling stability (a) and lithium content (b) of D-NCM111 after pre-removal of PVDF binder with and without lithium source, as well as the corresponding regenerated products 342

Figure I.4.C.14. Electrochemical cycling of 10% chemically delithiated NCM 111 with 3 wt.% PVDF binder and 5 wt.% carbon black after various annealing procedures. Pristine material is pure... 342

Figure I.4.C.15. Electrochemical rate performance of 10% delithiated NMC 111 with 3 wt.% PVDF binder and 5 wt.% carbon black after heat treating with a) 15 wt.% LiOHㆍH₂O, and... 343

Figure I.4.C.16. Triboelectric separation operating 344

Figure I.4.C.17. Adjustable baffle system 344

Figure I.4.C.18. Yield vs. applied voltages for NMC/LMO separation 345

Figure I.4.C.19. Results of triboelectric separation of NMC111 and LMO 345

Figure I.4.C.20. Yield vs purity curves for separations of selected cathode mixtures 346

Figure I.4.C.21. Recovered mass and purity of magnetic and non-magnetic fractions 346

Figure I.4.C.22. Purity and yield of each LMO rich and NMC111 rich fractions 347

Figure I.4.C.23. SEM image of 45-125 μm shredded copper foil 348

Figure I.4.C.24. Mass percent of copper added to cathode powder 348

Figure I.4.C.25. Separations conducted at 7 different rotational speeds 348

Figure I.4.C.26. Mass percentage of copper remaining after classification at different rotational speeds 349

Figure I.4.C.27. Recovery of pristine cathode materials at different Ph using collector A, B, and C 350

Figure I.4.C.28. XRD analysis of black mass. Assessment is summarized in the preceding table 352

Figure I.4.C.29. SEM/EDX analysis of the black mass cathodes 353

Figure I.4.C.30. Annealing at 800℃ for 20h, the only observed change in the mixture was that the structure of layered LiNiO 2 converted to a disordered rock salt structure 355

Figure I.4.C.31. Effect of nickel salt on the formation of the desired 622 phase (black - nickel sulfate; red - nickel acetate) 355

Figure I.4.C.32. Images showing (a) the SolveX process for the delamination of cathode materials from aluminum current collector and (b) the delaminated electrode of different sizes.... 356

Figure I.4.C.33. SEM-EDX results for the recovered cathode materials 357

Figure I.4.C.34. Characterizations on the recovered aluminum foils. (a) XRD pattern, (b) SEM image, (c) EDX image, and (d) EDX spectra 357

Figure I.4.C.35. Voltage profiles for the recovered NMC622 358

Figure I.4.C.36. Effect of shredding 358

Figure I.4.C.37. (a) Recovered black mass and aluminum foil via the SolveY process. Characterizations on the recovered black mass: (b) FTIR, (c) SEM, and (d) EDX mapping 359

Figure I.4.C.38. Diagram of benchtop fluidized magnetic separation apparatus 360

Figure I.4.C.39. Purity of graphite powder as a function fluidization time for 50/50 and 80/20 mixtures 360

Figure I.4.C.40. Triboelectric separation operating principles 361

Figure I.4.C.41. Adjustable baffle system 361

Figure I.4.C.42. Data tables for triboelectric separation of graphite 361

Figure I.4.C.43. Composition of electrolytes as determined by NMR recovered from commercial cells with different heat treatments under an argon atmosphere 362

Figure I.4.C.44. Full cell cycling results from electrolyte recovered from commercial cells dried at 90℃ under air, and 100℃ under vacuum compared to gen 2 electrolyte (1.2 M LiPF6... 363

Figure I.4.C.45. Full cell cycling results of recovered electrolyte from commercial cells dried at 90℃ under argon with different additives. The additives are VC (2 wt.% vinylene carbonate),... 363

Figure I.4.C.46. Cycle life of the 800 mAh pouch cell 365

Figure I.4.C.47. Li/transition metal ratio in the rinsed NMC622 cathodes 365

Figure I.4.C.48. First cycle voltage profile a) and dQ/dV curve of the rinsed electrodes b) 366

Figure I.4.C.49. Cycle life of the coin cells with fresh electrolyte a) and voltage profile at the end of 00 cycles b) 366

Figure I.4.C.50. Morphology of electrodes washed by various solvents 367

Figure I.4.C.51. Specific capacity (left) and HPPC ASI at 50% DoD (right) for the baseline electrodes (NMC622 and SLC1520P) under test in coin cells (single-sided) and 500-mAh pouch cells... 368

Figure I.4.C.52. Quantifying lattice strains as a function of statistical spreads in grain orientation provides detailed information about wear down of cathodes with resolutions down to the primary... 369

Figure I.4.C.53. Superior Graphite/Toda 1520P/NMC-111, 532, 622, and 811 heat generation curves for a 2C full discharge (2a - top) and 2C full charge (2b - bottom) 371

Figure I.4.C.54. Efficiency of 1520P/NMC cells under Various Charge/Discharge Currents over an SOC range of 80% to 20% 372

Figure I.4.C.55. Simulated global Co reserves over the time period 1998-2040. Results of 3,427 sensitivity runs are shown 374

Figure I.4.C.56. LIBRA Model Interface 375

Figure I.4.C.57. LIBRA Model Sensitivity Analyses 376

Figure I.4.C.58. NREL's updated supply chain model resultd (Sources: NREL Analysis; Campagnol, N. et al. 2017; BNEF 2019; LME 2019; Daly, T. 2019; Stringer, 2019) 377

Figure I.4.C.59. Test matrix developed for evaluating ReCell baseline electrodes in coin-cell format 378

Figure I.4.C.60. Summary of the discharge capacity from the full-cell coin-cell test matrix results for pristine NMC111 versus SLC1520P graphite under the Life Cycle test protocol (see legend for details) 378

Figure I.4.C.61. Summary of the discharge capacity from the full-cell coin-cell test matrix results for pristine NMC111 versus SLC1520P graphite under the Aging test protocol (see legend for details) 379

Figure I.4.C.62. Summary of HPPC ASI from the full-cell coin-cell test matrix results for pristine NMC111 versus SLC1520P graphite under the Life Cycle test protocol (see legend in Figure 2 for details) 379

Figure I.4.C.63. Single-layer pouch cells made with 1 wt.% metallic impurity in anode and cathode electrodes for micro- calorimetry studies at NREL 380

Figure I.5.A.1. (a) Picture of assembled NMR experimental setup (b) diagram of experimental setup 386

Figure I.5.A.2. (a) 19F NMR of Gen 2 electrolyte heated at 80℃ for increasing lengths of time (b) Integrated peak area of PF5-Lewis base species relative to PF6 387

Figure I.5.A.3. (a) 19F spectra after aging of, from bottom to top: Gen 2 + NMC @ 55℃, Gen 2 @ 55℃, Gen 2 + H₂O @ 55℃, and Gen 2 @ 80℃ (b) Peak width at half maxima of different... 388

Figure I.5.A.4. Chemical structure of cyclotriphosphazenes, and the derivatives synthesized for this experiment 388

Figure I.5.A.5. (a) Integrated peak area of PF5-Lewis base species relative to PF6- for three different electrolyte systems (b) dQ/dV of the first cycle of a Gr/Li half cell with increasing... 389

Figure I.5.A.6. (a) Capacity retention and (b) coulombic efficiencies of NMC622/Gr cells when cycled at 55℃ with phosphazene additives 389

Figure I.5.A.7. Capacity rention and coulombic efficiencies of PzTFE in combination with (a) vinylene carbonate, (b) 1,3- propanesultone, and (c) triallylphosphate 390

Figure I.5.A.8. Area-specifc of PzTFE in combination with (a) vinylene carbonate, (b) 1,3-propanesultone, and (c) triallylphosphate 390

Figure I.5.B.1. Analysis of reversible and irreversible Li plating along with capacity from graphite delithiation as a function of OL extent. (a) 1.5% OL (c) 5.5% OL. (b) Capacity associated with... 394

Figure I.5.B.2. Focused-ion beam SEM (FIB-SEM) images of positive electrodes before (left) and after 450 cycles at 4C (middle) and 6C (right). Increasing the rate of charge led to distinc... 395

Figure I.5.B.3. Coin cell data for various electrolyte blends identified using AEM. Cells were cycled using Round 2 positive and negative electrode laminates from Argonne. Cell capacity is shown... 396

Figure I.5.C.1. Model predictions for achievable energy density during 4C and 6C constant current charging to 4.2V for cells with a loading of 3 mAh.cm-² (left) and 4 mAh.cm-² (right).... 400

Figure I.5.C.2. Comparison of gas-titration results from LBNL and macro-homogeneous model predictions for lithium plated during 3 cycles vs. charge rate. Half-cells were fully lithiated... 401

Figure I.5.C.3. (Left) Lithiation heterogeneity induced by particle size distribution: large particle lithiation is lagging due to solid-sate diffusion limitation. (Right) Anode state of charge associated... 402

Figure I.5.C.4. (a) Anode state of charge associated with lithium plating onset calculated for different dual coating architectures and compared with non-graded reference case, (b) schematic... 403

Figure I.5.C.5. (a) Illustration showing the design of cell for operando high-speed X-ray diffraction (XRD). (b) Illustration showing a magnified view of the cell, and a further magnified view... 404

Figure I.5.C.6. (a) Illustration showing the depth of the electrode with yellow points highlighting XRD measurements. The highlighted yellow region indicates where Li plating was present and... 404

Figure I.5.C.7. Effect of charging protocol on charge capacity and minimum (phis-phie) in 10 mins. (left) 2 steps and 3 steps constant current charging. (right) positive pulse current charging 405

Figure I.5.C.8. Full cell discharge capacity measured at C/3 using NMC-622 and graphite electrodes from Targray following a 5C charge to 4.2 V 406

Figure I.5.C.9. Cyclic voltammetry verifies electrochemical stability of Round-2 solvents against Li/Li+ 406

Figure I.5.C.10. Fast charge algorithms used to assess heat generation and efficiency 407

Figure I.5.C.11. Efficiency, heat rate, and capacity under various constant-current discharge and charge rates 408

Figure I.5.C.12. (a) Grey-level image after contrast correction, vertical direction is along electrode thickness, with lithium plating on top, and graphite layer at the bottom. (b) After segmentation.... 409

Figure I.5.D.1. Rate performance and coulombic efficiencies of TNO and TNO@C half cells (electrode loading 2.3 mg cm-²)///////////// 412

Figure I.5.D.2. Rate performance and coulombic efficiencies of NMC622 (18 mg/cm²) and TNO@C (13.5 mg/cm²) half-cells 412

Figure I.5.D.3. Discharge capacities and coulombic efficiencies of full cells (a) based on TNO and TNO@C with the same loading of 9.41 mg cm-² and (b) based on TNO@C with different mass... 413

Figure I.5.D.4. (a) Voltage profiles and (b) cycling performance of NMC622/TNO@C full cells under different charging protocols with a total charge time of 10 min and discharge at C/3 413

Figure I.5.D.5. Effect of additives on capacity, coulombic efficiency and cycling stability of NMC622/TNO@C full cells at 5C fast charge condition 414

Figure I.5.D.6. Rate performance of (a) p-TNO and b-TNO half-cells with the same TNO loading of 10 mg/cm² ; (b) b-TNO half- cells with various TNO loadings 414

Figure I.5.D.7. (a) Rate performance and (b) Electrochemical Impedance Spectroscopy (EIS) of b-TNO half-cells with different TNO mass loadings 415

Figure I.5.D.8. Charge-discharge capacities, coulombic efficiencies, and energy densities of (a) p-TNO and b-TNO full cells with the same TNO loading of 10 mg/cm² ; and (b) b-TNO full-cells... 415

Figure I.5.E.1. Voltage and Current during rate capability testing of NMC/Graphite UMich cell 419

Figure I.5.E.2. dQdV of charge steps during rate capability testing of NMC/Graphite cell 419

Figure I.5.E.3. Rate capability and long 6C/1C cycling for NCA/Hard Carbon cell 420

Figure I.5.E.4. Charge dQdV for NCA/Hard Carbon cells 421

Figure I.5.E.5. Efficiency for NMC/Graphite and NCA/Hard Carbon cells 421

Figure I.5.E.6. Temperature profile for 6C/1C cycling, with and without temperature control plates 422

Figure I.5.E.7. Cycle to cycle efficiency for 6C/1C cycling, with and without temperature control plates 423

Figure I.5.F.1. The bulk composition and surface composition are analyzed by XRF and TEM-EDS mapping 425

Figure I.5.F.2. The EELS spectra offset for clarity to show the intensity of the Mn and Ni are changing with position along the primary particle 426

Figure I.5.F.3. (a) The initial capacity of FCG85-5-10; (b) cycle data of plain FCG Ni85 material, and after a treatment with Al and Ti. (c) and (d) The qQ/dV of the untreated FCG and FCG... 426

Figure I.5.F.4. FCG 85-5-10 and FCG 85-10-5 (Ni-Mn-Co) comparing the first cycle load curve, capacity retention during coin cell cycling, and half-cell rate performance 427

Figure I.5.F.5. Graph comparing the two in situ cell HE-XRD (003) peak positions during charge and discharge. The shape during charge and discharge are obviously different 427

Figure I.5.F.6. (a) The cycle data for different LiDFOB added in Gen2 electrolyte tested in a half cell. (b) The rate performance comparison of Gen2 and Gen2 electrolyte with 1wt% LiDFOB 428

Figure I.5.F.7. 15AH pouch cells energy density and energy retention over 500 cycles tested under XFC cycling conditions 428

Figure I.5.G.1. (a-i) SEM backscatter images of graphite electrodes(a,d,g,) pristine, (b,e,h) sputter coated with 10 nm Cu, and (c, f, i) sputter coated with 10 nm of Ni. Images a-i show the... 431

Figure I.5.G.2. (a, b) Representative atomic force microscopy images of ultra-flat SiO₂ wafers sputtered with (a) 10 nm of Cu, and (b) 10 nm of Ni. (c-f) XPS spectra of (c, d) Cu 2p 3/2... 432

Figure I.5.G.3. Operando XANES results for (a-c) Cu-graphite electrodes and (d-f) Ni-graphite electrodes during a formation cycle at C/5 rate between 0.01 - 1.4 V vs. Li/Li + . (a, d) Voltage... 433

Figure I.5.G.4. LABE SEM images displaying the morphologies of Li plated at -20 mV on the (g) uncoated graphite, (h) Cu- coated graphite, and (i) Ni-coated graphite electrodes 434

Figure I.5.G.5. Cycling of single layer full cells with NMC 622 cathodes and uncoated graphite (control), Cu-graphite, or Ni- graphite anodes between 3.0 - 4.3 V at C/2 rate 434

Figure I.5.G.6. Cycling of single layer full cells with NMC 622 cathodes and uncoated graphite (control), Cu-graphite, or Ni- graphite anodes between 3.0 - 4.3 V with 10 minute charge (CC/CV)... 435

Figure I.5.G.7. EDS mapping images for the top down view of Cu and Ni deposited on graphite. (a-f) Ni deposited on graphite with thickness of 5, 10 and 20 nm. (g-l) Cu deposited on graphite... 435

Figure I.5.H.1. a) DEMS titration setup schematic. b) Measured dead Li amount after 2 C/10 formation cycles and 3 cycles of varying intercalation rates to 372 mAh/g and deintercalation to 1.5 V.... 438

Figure I.5.H.2. a) 1st cycle charge/discharge voltage profiles of the in situ optical cell when cycled at C/10 rate between 0.01 and 3 V, b) and c) in situ optical images of the graphite electrode... 439

Figure I.5.H.3. (a) Schematic of X-ray tomography cell. (b) Slice of an X-ray tomogram of micro-cell after 3 formation cycles (C/10 intercalation, C/5 deintercalation) and (c) slice of an X-ray... 440

Figure I.5.H.4. a) The evolution of thermal resistance in 100+ cycles, b) 3w sensor on separator for ex situ measurements, c) the impact of external pressure on thermal contact resistance 440

Figure I.5.H.5. (a) Graphite/Li cell cycling to generate OCV data after fast charge for various SOC and c-rates. (b) Coulombic efficiencies (CE) for these half cell cycles. We believe the drop... 441

Figure I.5.H.6. OCV's (top row) and differential OCV's (bottom row) during relaxation after graphite intercalation at 1C, 2C, and 6C. Each window shows the OCV's after intercalation to the designated SOC 442

Figure I.5.H.7. (a) Lithiation voltage profiles for graphite electrode between 0.20 and 0.00 V, inset showing full profile from 1.00 to 0.00 V, (b) charge voltage profiles for NMC electrode,... 443

Figure I.5.H.8. (a) CV formation of the basal HOPG/Li half-cell. (b) Current ramp behavior of basal HOPG/Li half-cell, after CV formation. (c) Image of cell 444

Figure I.5.H.9. SEM (a)(b) fracture surface and (c) surface images of freeze tape cast graphite anode. Graphite layer is 150 μm thick, showing vertical pore channels. Graphite columns are... 444

Figure I.5.I.1. The ionic conductivities of 5 electrolytes under different temperatures: (a) the ion conductivities at 20℃; (b) the ion conductivities at 30℃; (c) the ion conductivities at 40℃ 447

Figure I.5.I.2. (a) The rate performance for the 5 electrolyte systems with LiPF6 concentration of 1.2 M. (b) the long-term cycling performance with different electrolytes 447

Figure I.5.I.3. (a) Conductivity of LiFSI and LiPF6 in (EC:EMC) (30:70 wt%) as function of concentration and temperature. (b) Voltage (V) and Current (I) versus charging time for cells charged... 448

Figure I.5.I.4. (a) Charge (different C rate) and discharge voltage curves (all at C/2) of NMC/graphite cells with LiPF6 and LiFSI electrolyte. (b) Long term cycling performance of the cells with... 449

Figure I.5.I.5. (a) Voltage (V) and Current (I) versus charging time for cells charged at 6C with time cut-off of 10 minutes. (b) Cycling performance of the 500 mAh at fast charging rate 450

Figure I.5.J.1. 15AH pouch cells energy density and energy retention over 500 cycles tested under XFC cycling conditions 453

Figure I.5.J.2. Projects final 21AH Generation 1 pouch cells capacity and energy density cycling results, (including retention) over 500 cycles of 6C/1C conditions with periodic reference cycles 454

Figure I.5.J.3. Concentration gradient cathode with NMC ratio of 6:3:1 tested in half cell at 4.3V and 4.4V with and without a lower resistance titania coating 454

Figure I.5.K.1. Electrode composition and design parameters for Round 2-Batch 1 pouch cell design. The Round 1 electrodes had the same composition but had less mass loading (and thickness) 458

Figure I.5.K.2. Comparison of optical and XRD spatial map of the anode, showing Li intensities across the electrode 459

Figure I.5.K.3. Photo of the fully transparent (left, PET/PE [Kapak SealPAK 400]) and the windowed (right, PP window heat- sealed on layered pouch material) pouch cells designed for brief... 460

Figure I.5.K.4. Correlation between mass of plated Li (as a % of initial mass of Li before cycling) and capacity fade in Round 2 cells. While cells charged at 4C (red) show negligible plating... 461

Figure I.5.K.5. microCT of a Round 2 anode cycled at the 9C charging rate for 450 cycles. (a) Projection of the tomographic reconstruction showing anode (gold) and Li in the form of LiOH... 462

Figure I.5.K.6. Left: schematic depicting a graphite anode strip with different regions of lithium plating indicated by bright regions. The strip was vacuum sealed in a glass capillary in a kapton... 462

Figure I.5.K.7. (a) The configuration of operando pressure measurement: a multilayer pouch cell is stacked with a metal plate and load cell and contained in a bench vise to define a fixed... 463

Figure I.6.A.1. Overview of BTMS relevance 467

Figure I.6.A.2. BTMS System Modeled in FY19 468

Figure I.6.A.3. Aggregate demand by time of day for EV charging 470

Figure I.6.A.4. Utility rate structure for PG&E customers, demonstrating the time-variability in electricity price and demand charges 470

Figure I.6.A.5. Block schematic based on signal flow graph representing the overall electrical and thermal model for the entire system 471

Figure I.6.A.6. Illustrative discharge curves for sensible and latent thermal storage materials (left) and for electrochemical and capacitor energy storage (right). This shows a drop in potential... 473

Figure I.6.A.7. Discharge curves at different C rates, and corresponding Ragone plots for electrochemical batteries (top) and phase-change thermal energy storage (bottom). V OC = open-circuit... 473

Figure I.6.A.8. Capital cost for EV charging station with BTMS 474

Figure I.6.A.9. EV charging demand shifting with a behind-the-meter battery 474

Figure I.6.A.10. Block schematic of an electric vehicle supply equipment 477

Figure I.6.A.11. Block-tree-type categorization of the various aspects of installation-oriented design of EVSE 479

Figure I.6.A.12. Capacity data throughout life testing is shown for LFP/graphite EV cells DST cycled to full depth of discharge 481

Figure I.6.A.13. INL cycling data at 1C/1C is shown overlaid on 5C/10C cycling data published by the developer 481

Figure I.6.A.14. Calendar- and cycle-life data for LMO-NMC/LTO cells 482

Figure I.6.A.15. Cycle-life data for LMO/graphite cells 482

Figure I.6.A.16. Cycle-life data for NMC-LMO/graphite cells 483

Figure I.6.A.17. Preliminary test matrix for cells with 6-XFC and 1 MWh ESS and accelerated aging conditions 484

Figure I.6.A.18. Cycle-life testing results for the NMC/graphite cells 485

Figure I.6.A.19. Calendar testing results for the NMC/Graphite cells, shown with the baseline cycling condition results 485

Figure I.6.A.20. Cycle-testing reference-performance-test (RPT) capacity results for the NMC/LTO cells 486

Figure I.6.A.21. Cycle-by-cycle testing capacity results for each cycling condition for the NMC/LTO cells 486

Figure I.6.A.22. LFP/graphite cycling results 487

Figure I.6.A.23. Differential capacity test for LFP/graphite cells 487

Figure I.6.A.24. Capacity decay rate for each LFP/graphite cell type and condition 488

Figure I.6.A.25. Example of physics-based life predictive model (NREL) applied to 2012 Nissan Leaf fast charge data (INL) 490

Figure I.6.A.26. Example local model fit of Kokam 75-Ah cell data using machine-learning elastic-net regularization algorithm 491

Figure I.6.A.27. Voltage measurement as a function of cycle using the original data (blue) and clean data after removal of data outliers (orange) 492

Figure I.6.A.28. Comparison of predicted and observed reference performance test capacity after 900 cycles for the test and training datasets. Analysis performed using Nissan Leaf test data 492

Figure I.6.A.29. Comparison of observed and predicted reference performance test capacity for each cell in the analysis. Of note is that the data were collected at three different temperatures... 493

Figure I.6.A.30. (a) Expanded graphite (EG), thermally expanded after acid intercalation. EG flakes are compressed in (b) die fixture using (c) pneumatic press. (d) Graphite matrix is soaked... 494

Figure I.6.A.31. DSC curves (melting) of several PCM composites with varying mass fraction of PCM 495

Figure I.6.A.32. Experimental setup (left), and CAD rendering showing each component 496

Figure I.6.A.33. 4ergy storage capacity during cycling 496

Figure I.6.A.34. Experimental hardware in the loop (HIL), focusing on multi-system level integration of the building and behind-the-meter storage assets. In this case, storage assets are in.... 497

Figure I.7.A.1. Simplified process diagram for LMO production using sol-gel method (P2) 504

Figure I.7.A.2. Simplified process diagram for LMO production using solid state synthesis (P1) 504

Figure I.7.A.3. Effect of cathode active material and temperature on the area specific impedance measured in coin cells 505

Figure I.7.A.4. Comparison of estimated costs of lithium ion battery packs 507

Figure I.7.B.1. Average, relative capacity vs. cycle count for cells undergoing XCEL and standard charging 511

Figure I.7.C.1. Force against mechanical test apparatus of a cell fixed in place within the test fixture as temperature is increased. Used to evaluate cell swelling, this shows little to no swelling... 514

Figure I.7.C.2. Voltage vs temperature of cell tested in Figure I.7.C.1 above. A slight drop in voltage is observed with increasing temperature, indicating potential feasibility of rendering the cell... 515

Figure I.7.C.3. DPA and abuse test behaviors of cells with reduced n:p ratios to force significant lithium plating. Visible deposits are observed in the low n:p cell, with a significant thermal... 516

Figure I.7.D.1. Efficiency summary of cells tested at 30℃ in NREL's calorimeters 520

Figure I.7.D.2. Efficiency of silicon blended cells tested at 30℃ in NREL's calorimeters under various charge/discharge currents and SOC ranges 521

Figure I.7.D.3. Calorimeter normalized heat rate for a graphite/high nickel content NMC cells under C/10 charge 522

Figure I.7.D.4. Large format graphite/NMC cell under a 3.2C fast charge. The calorimeter test temperature was 30℃ 523

Figure I.7.D.5. Infrared image of lithium battery cell (graphite-silicon/high nickel content NMC) at the end of a 2C discharge 524

Figure I.7.E.1. Pictorial of cathode particle cross-sections produced in MERF 527

Figure I.7.E.2. Electrochemical performance high-nickel content NMC cathode powders produced by MERF compared to a baseline NMC811 (Targray). All electrodes and pouch cells were... 528

Figure I.7.E.3. Images of a researcher scraping the laminate off of the substrate foil in an inert glovebox and the parts used for the DSC experiment 528

Figure I.7.E.4. Test conditions and sample preparation procedure used for DSC experiment 529

Figure I.7.E.5. Voltage profiles and energy-capacity relationship for NMC111, NMC622, NMC811, NMC811-core-gradient, NMC811-core-shell, and NMC811-core-multishell with respect to the... 529

Figure I.7.E.6. Exothermic heat released (integrated DSC peak area), half-cell charged specific capacity, and half-cell voltage before cell disassembly DSC results (left) and total heat released... 530

Figure I.7.E.7. Cell design options the CAMP Facility explored for coating materials onto an existing electrode. The green lines indicate the interface of film coating on to the anode 531

Figure I.7.E.8. Voltage profiles of graphite electrodes with selected ceramics (Al₂O₃ and MgO) coated graphite electrodes coatings vs. lithium metal made in coin cells. The left plot show... 531

Figure I.7.E.9. SEM images of the surface of the graphite electrodes with and without various coatings. The various ceramic coatings appear to provide a uniform coverage over the surface... 532

Figure I.7.E.10. Cross section SEM images of the various ceramic coatings generally indicate a more uniform thickness is achieved using the comma coater compared to a hand coating 533

Figure I.7.E.11. SEM cross section image (left) and a surface SEM image (right) for the Al₂O₃ coating on the graphite anode. The image was provided by Nancy Dietz Rago (PTF) 533

Figure I.7.E.12. Electrochemical performance of the baseline full-cell pouch-cell build using a typical polymer separator with no ceramic coating on the anode against 8 other data sets where... 533

Figure I.7.E.13. Coating methods used in the CAMP Facility for coating ceramics onto graphite electrodes 534

Figure I.7.E.14. Influence of oxide nanoparticles on the electrochemical cycling of NCM811//Gr cells 536

Figure I.7.E.15. Influence of oxide nanoparticles on the Area specific impedance (ASI) of NCM811//Gr cells. ASI for Gen2 electrolyte (panel a) is reproduced in gray in panels b-h for comparison.... 537

Figure I.7.E.16. Correlation of (a) initial ASI at 3.7 V (y-axis) and ASI rise (x-axis) and (b) ASI rise (y-axis) and capacity retention (x-axis) for NCM811/Gr cells containing various electrolytes 537

Figure I.7.E.17. Representation of the effect of oxide particles on cell performance 538

Figure I.7.E.18. The effect of added water on electrochemical performance of NCM811//Gr cells. Cycle life (panels a, b, and c) and impedance rise (panels d, e, and f) for multiple cells... 540

Figure I.7.F.1. a) Cycle performance of SiO/NCM523-LFO full cells, b) discharge capacity with C/10 rate as a function of time 544

Figure I.7.F.2. a) 3rd cycle voltage profile of NMC and NCA half cells, b) cycle performance of NMC and NCA full cells 545

Figure I.7.F.3. DSC of NMC (left) and NCA (right) for delithiated material 546

Figure I.7.F.4. a) Pouch cell assembly, b) prelithiation setup, c) electrode before and after prelithiation 546

Figure I.7.F.5. a) 1st cycle differential capacity and b) Coulombic efficiency plots of pristine and prelithiated graphite electrodes 547

Figure I.7.F.6. (a) Differential capacity plot and (b) cycle performance of full cells with prelithiated graphite electrode 547

Figure I.7.F.7. (a) Differential capacity plot and (b) cycle performance of full cells with prelithiated SiO electrode 548

Figure II.1.A.1. Battery Performance and Cost (BatPaC) model utilized to establish relevance by connecting pack to anode targets 563

Figure II.1.A.2. Program participants including Laboratories, research facilities, and individual contributors 564

Figure II.1.A.3. Lithiation capacity versus lithium metal for various graphite-free silicon electrodes fabricated by the CAMP Facility. These cells were cycled between 0.05 to 1.5 V or 0.1 to... 566

Figure II.1.A.4. Full cell results using the silicon DeepDive protocol for the high-silicon graphite-free anodes and 15 wt.% Si in graphite composite. All anodes were tested against a capacity... 567

Figure II.1.A.5. (Left) Raman mapping of pristine electrode. (Right) - cycling data for the electrodes 568

Figure II.1.A.6. Variations in coating quality as a function of wet gap setting for 23 wt.% SFG-6-L flakey graphite with 60 wt.% silicon 569

Figure II.1.A.7. Final specification for the two trial electrodes produced in this quarter based on 23 wt.% electrochemically active carbon (SFG-6-L flakey graphite and hard carbon) with 60 wt.% silicon 569

Figure II.1.A.8. Lithiation & delithiation capacity versus lithium metal for 60 wt.% Si electrodes with 23 wt.% of either SFG-6- L flakey graphite or hard carbon. Comparison made to 80 wt.%... 570

Figure II.1.A.9. Viscosity vs. shear rate for 80 wt.% Si using LiPAA binder with PAA dispersant (LN3174-115) and without PAA dispersant (LN3174-116). Rheology measurement performed... 571

Figure II.1.A.10. Viscosity vs. shear rate for a SFG-6L graphite electrode (no silicon) using LiPAA binder dispersant (black curve, LN3174-111), and for a SFG-6L graphite electrode (no silicon)... 571

Figure II.1.A.11. Viscosity versus shear rate curve for silicon electrode slurry. Inset schematic from left to right depict 1) extremely collapsed polymer chains on a silicon particle, 2) a mixture... 573

Figure II.1.A.12. Intensity versus Q ultra small angle neutron scattering plots of (a) 14 wt% solution of 450,000g/mol poly(acrylic acid) in deuterated water at 0 Hz and 30 Hz and (b) a 10 wt%... 574

Figure II.1.A.13. Specific delithiation capacity profiles of Li half cells using electrodes containing 73 wt% graphite, 15 wt% Si, 10 wt% modified PAA binders, and 2 wt% C45 over 100 cycles... 576

Figure II.1.A.14. (a) Small angle X-Ray scattering (SAXS) profiles for binder solutions; (b) Sample information and Rg of the modified PAA solutions 577

Figure II.1.A.15. (a) Sample information and Rg of PAA solutions; (b) Specific delithiation capacity profiles of half cells using electrodes containing 73 wt% graphite, 15 wt% Si, 10 wt% PAA... 578

Figure II.1.A.16. Synthetic scheme of PAA analogues with modified properties 578

Figure II.1.A.17. Electrochemically Induced Fracture Method. LEFT: Electrochemical cycling conditions used to induce fracturing, where arrows represent times where samples were analyzed... 579

Figure II.1.A.18. Limitations of the linear elastic fracture mechanics (LEFM) model based on the thickness of the silicon wafer. For thick wafers (1 mm), crack propagation occurs along... 579

Figure II.1.A.19. TOP: Chemical structures of polymer capping layers used in this study; MIDDLE: Plan view SEM images. BOTTOM: Cross-sectional SEM images after FIB milling. The trench... 580

Figure II.1.A.20. LEFT: Cantilever Beam Test (CBT) instrument showing the cantilever bound to a polymer-capped silicon wafer; MIDDLE: Schematic of the single cantilever beam method.... 581

Figure II.1.A.21. Synthesis of surface-functionalized silicon nanoparticles SF-SiNPs 582

Figure II.1.A.22. (a) TEM images of H-SiNPs and (b) Si-C3-(EO)₁-epoxy SiNPs (the specimens were prepared from a 1 mg g-¹ SiNP aqueous suspension by casting the nanoparticles on... 582

Figure II.1.A.23. Electrochemical performance of Si composite electrodes. (a) Cycling performance and Coulombic efficiency, and (b) Nyquist plots of H-SiNP and SF-SiNP electrodes after 150 cycles 583

Figure II.1.A.24. SEM images and EDX elemental mappings (colored images) of composite electrodes. (a) H-SiNP anode and (b) surface functionalized Si-C3-(EO)₂-epoxy SiNP anode before... 585

Figure II.1.A.25. (a) Capacity retention and Coulombic efficiency of the pure silicon anodes using H-SiNPs and Si-C3-(EO)₄- epoxy SiNPs as active material, and (b) F1s XPS spectra of H-SiNPs 586

Figure II.1.A.26. (a) Cycling performance of Si-Sn and Si films of similar thickness. (b) XRD patterns of co-sputtered SixSn1-x thin films along with Sn reference 587

Figure II.1.A.27. SEM images of co-sputtered SixSn₁-x thin films 587

Figure II.1.A.28. Charge-discharge voltage profiles of the co-sputtered SixSn₁-x thin films during the first two cycles 588

Figure II.1.A.29. (a) Lithiation capacity, (b) delithiation capacity, (c) coulombic efficiency and (d) capacity retention of co- sputtered SixSn₁-x thin films upon cycling 588

Figure II.1.A.30. dQ/dV plots of co-sputtered Six Sn₁-x thin films during the first two cycles 589

Figure II.1.A.31. C 1s spectra from the 15 wt% Si/C, 70 wt% Si/C, 90 wt% Si/C, 70 wt% Si/C/PEG, 70 wt% Si/C/PVdF, and 70 wt% Si/C/PFO-based electrodes 591

Figure II.1.A.32. Si 2p spectra from the 15 wt% Si/C, 70 wt% Si/C, 90 wt% Si/C, 70 wt% Si/C/PEG, 70 wt% Si/C/PVdF, and 70 wt% Si/C/PFO-based electrodes 591

Figure II.1.A.33. O 1s spectra from the 15 wt% Si/C, 70 wt% Si/C, 90 wt% Si/C, 70 wt% Si/C/PEG, 70 wt% Si/C/PVdF, and 70 wt% Si/C/PFO-based electrodes 592

Figure II.1.A.34. F 1s spectra from the 15 wt% Si/C, 70 wt% Si/C, 90 wt% Si/C, 70 wt% Si/C/PEG, 70 wt% Si/C/PVdF, and 70 wt% Si/C/PFO-based electrodes 593

Figure II.1.A.35. Electrode potential changes during the first lithiation/delithiation of half-cells with the 15 wt% Si / C, 70 wt% Si / C, 90 wt% Si / C, 70 wt% Si / C/PEG, 70 wt% Si / C/PVdF,... 594

Figure II.1.A.36. Differential capacity (dQ/dV) as a function of voltage during the first lithiation of half-cells with the 15 wt% Si / C, 70 wt% Si / C, 90 wt% Si / C, 70 wt% Si / C/PEG, 70 wt%... 594

Figure II.1.A.37. Comparing the discharge capacity vs. cycle number for full cells containing (a) 15 wt% Si / C, 70 wt% Si / C, 90 wt% Si / C and (b) 70 wt% Si / C, 70 wt% Si / C/PEG, 70 wt%... 595

Figure II.1.A.38. Full-cell electrochemical test results. Cells in panels (a)-(d) consist of NMC532 cathodes and Si or Graphite anodes (formation cycles are not shown). Cells in panels (e)-(h)... 598

Figure II.1.A.39. Discharge capacities of full cells using GenF, GenFM, GenFA, and GenFC electrolytes with extended cycles. (a) The full cells consist of NMC532+Si electrodes were cycled between... 599

Figure II.1.A.40. Frequency shift for the early SEI formation for the 0.2 M Zn(TFSI) and 0.2 M Mg(TFSI)2 as electrolyte additives to the baseline electrolyte (Gen2+10%FEC) on a Si thin film... 599

Figure II.1.A.41. Voltage, current and frequency versus time plots of the early SEI formation of Zn(TFSI) 2 additive into the Gen2 electrolyte from OCV to lithiation depth of 0.4 V 600

Figure II.1.A.42. Schematics of the gradient polarity solvent wash technique 601

Figure II.1.A.43. Gradient polarity solvent wash was applied to a Cu electrode polarized to 10 mV Li/Li+ 602

Figure II.1.A.44. Three different scanning rates of CV at 1, 10 and 60 mV min-¹ were applied to the Cu electrodes respectively with baseline electrolyte and two additives-based electrolytes.... 602

Figure II.1.A.45. Si N-type disk electrode voltammetric results shown for the reductive side of the voltage window where SEI first cycle is shown. (a.) Slow CV at 6 μV/s between 0.01 to 1.5 V... 603

Figure II.1.A.46. (a.) Si N-type disk electrode voltammetric results shown for the oxidative side of the voltage window with 10 mM ferrocene in GEN2 + 10% FEC. (b.) RRDE result showing... 604

Figure II.1.A.47. (a.) Si N-type disk electrode and Pt ring RRDE results shown for the oxidative side of the voltage window with 10 mM ferrocene in GEN2 + 10% FEC. This SEI was grown using... 604

Figure II.1.A.48. Synthetic scheme of PAA analogues with modified properties 605

Figure II.1.A.49. Voltage and current versus time, showing the testing regimen used for these short tests 606

Figure II.1.A.50. Schematic of electrolyte extraction steps 606

Figure II.1.A.51. Molecular structure and properties of several diluents and the recipes of new LHCEs 607

Figure II.1.A.52. Charge-discharge curve, cycling stability, and Coulombic efficiency of DeepDive anodes in new LHCEs in half-cell (a-c) and full-cells (d-f) with NMC532 cathodes 608

Figure II.1.B.1. Energy per atom of two relaxed crystalline interfaces between i) SiO₂ (001) and Si (111), and ii) SiO₂ (110) and Si (100) as a function of SiO₂ film thickness 617

Figure II.1.B.2. Energy per atom of interfaces between i) amorphous SiO₂ and ii) crystalline SiO₂ (001) with Si (111) 617

Figure II.1.B.3. Energy per atom of slabs of a) LixSi and b) LixSiOy as a function of thickness, with the bulk energies shown to the right. Error bars shown represent 1 standard deviation... 618

Figure II.1.B.4. a) Schematic of film expansion during lithiation; b) Lithiation profile for amorphous Si films; c) Lithiation profile for amorphous SiO₂ films 619

Figure II.1.B.5. Left: Galvanostatic cycling results obtained with an O-ring cell and Si wafer anode as a function of current density at NREL (4-h half-cycles for 5 and 2 μAcm-², 12 h for 0.7 μAcm-²).... 620

Figure II.1.B.6. Cycling of Si wafer anodes with variation of SiO₂ coating thickness at 20 μAcm-² with no lower voltage cut-off. Top: 1st and 9th cycles as a function of SiO₂ thickness (left, middle),... 621

Figure II.1.B.7. Chronoamperometry at 0.01 VLi for different SiO₂ thicknesses. Photographs of selected samples at the end of testing are shown 621

Figure II.1.B.8. Changes in Si, Li, O, and F bonding studied by the XPS. Colors of the XPS curves correspond to the lithiation- delithiation stages in the voltage-time plot on the left (2 half-cycles,... 622

Figure II.1.B.9. Two-dimensional TOF-SIMS map of Li, Si, O, and carbon-containing sputtering fragments, along with the optical micrograph. The mapping area was 500x500 microns and... 623

Figure II.1.B.10. CV of 50-nm-thick SixLiyO films under slow CV. Conditions: 25℃, 10 μV/s, 50-nm Si/500-nm Cu/300-μm Si/20-nm Ti/200-nm Au WE, Li CE, Li RE 624

Figure II.1.B.11. CVs of a) 2nd cycle, b)7th cycle, and c) 14th cycle of SixLiyO samples under slow-scan CV (same conditions as above) 625

Figure II.1.B.12. Nyquist plots of SIO₂ film exposed to Gen-2 electrolyte at 30C for various times. Film evolution is very slow, with little change after several days 625

Figure II.1.B.13. Nyquist plots of SiO₂ film exposed to Gen 2 electrolyte at 60℃ (left) and 80℃ (right) over time. Both the electrical model and the film evolution are dramatically changed from... 626

Figure II.1.B.14. a) 1st-cycle and b) 2nd-cycle CV curves of Si, Si with native oxide layer, and four SiOx anodes with different oxygen level tested under the scan rate of 0.1 mV/s... 626

Figure II.1.B.15. Galvanostatic charge-discharge profiles of Si, Si with native oxide layer, and SiOx anode under the current of 1 C (6 μA) in the potential range of 0.05-1.5 V 627

Figure II.1.B.16. CV curves and galvanostatic charge-discharge profiles of Si prepared under different sputtering conditions under the scan rate of 0.1 mV/s in the potential range of 0.05-1.5 V 628

Figure II.1.B.17. A) Moire in situ cell design with PEEK pieces in white and the metal heating elements in beige. B) Current custom microscope with optical illumination arm complete. C) Schematic... 629

Figure II.1.B.18. A) Moire fringe pattern using 470-nm incident light for the Si wafer thermal expansion experiments. B) Cross-sectional average of the Moire fringe pattern given in A with the data... 630

Figure II.1.B.19. Summary of optimized nonthermal plasma growth conditions for preparing 30-nm-diameter Si NPs at gram scale 631

Figure II.1.B.20. Left: C65/Si ratio must increase as the Si NP size decreases to ensure an electrical percolation network for active anode material as the surface area/volume ratio increases.... 631

Figure II.1.B.21. (a) Normalized cycling data for a range of SiHX-terminated Si NP anodes. The data here have been normalized to their capacity at cycle number 50. (b) Scatter plot... 632

Figure II.1.B.22. (a) Representative Nyquist plots for Si NP-based anode half-cells with (red) and without (blue) an intentionally grown surface oxide (SiO₂) layer. The equivalent circuit used... 633

Figure II.1.B.23. Neutron PDF data collected for Li2SiO3 (top), Li2Si2O5 (middle), and Li4SiO4 (bottom) for the raw material (black line) and material exposed to electrolyte (red dashed line) 635

Figure II.1.B.24. a) Heat flow and voltage curves for NMC vs Paraclete-G18 coin cell subjected to electrochemical microcalorimetry. b) The cell capacities and generated heat per cycle derived... 637

Figure II.1.B.25. (a) Photograph of the 1-cycle, 200-mV, and 10-mV GenF or GenFM samples in the air-free holder used for micro-Raman analysis. (b) Optical micrographs of the samples... 638

Figure II.1.B.26. (a) ATR-FTIR and (b) DRIFTS-FTIR spectra of 1 cycle, 200 mV, and 10 mV GenF or GenFM samples 639

Figure II.1.B.27. XPS spectra of the Si electrodes cycled in GenF. Peak assignments are preliminary 640

Figure II.1.B.28. XPS spectra of the Si electrodes cycled in GenFM. Peak assignments are preliminary (N.A. denotes "not assigned") 640

Figure II.1.B.29. STEM EDS atomic % maps of particles of first-cycle GenFM sample 641

Figure II.1.B.30. STEM EDS spectra obtained from particles of 1-cycle GenFM sample 641

Figure II.1.B.31. Optical microscope images of composite electrodes after cycling and disassembly. Scale is visible in the width of the visible AFM cantilever, which measures 40 µm in width 642

Figure II.1.B.32. 5×5-µm AFM images and RMS roughness calculated from AFM images 642

Figure II.1.B.33. Summary of XPS measurements for the O 1s, Si 2p, and valence-band (VB) regions during in situ lithiation of 5-nm SiO₂ / Si(001) sample. For these measurements, the Li+ ion... 644

Figure II.1.B.34. (a) Summary of time evolution of SiO₂ O 1s binding energy and overpotential during VE-GITT (i.e., the pulsed in situ lithiation experiment). (b)-(f) O 1s core-level spectra at... 645

Figure II.1.B.35. (a) XPS spectra from the (a) O 1s and (b) Si 2p core levels, as well as the (c) valence-band regions. The top row of spectra (black traces) show spectra from the pre-lithiated... 646

Figure II.1.B.36. Schematic illustration of the observed change in interfacial band alignment that occurs during early-stage lithiation of the 5-nm SiO₂ / Si(001) model-system interface 646

Figure II.1.B.37. Schematic representation of the electrochemical cell set up, cell components, and protocols employed in the Corrosion Task 648

Figure II.1.B.38. (a) First lithiation-delithiation process of 500-nm Si thin film on Cu foil observed by cyclic voltammetry by using four different electrolyte solutions. A scan rate of 0.1 mV s-1... 649

Figure II.1.B.39. Application of Protocol 1 (GCPL + CA) to the 500-nm Si thin-film model electrode by using (a, b) 1.2 M LiPF6 EC:EMC (3:7 wt%), (c, d) 1.2 M LiPF6 EC:EMC (3:7 wt%) + 10%... 650

Figure II.1.B.40. Summary of XPS measurements on 50-nm a-Si / 3-nm SiO₂ films at varying states of lithiation and delithiation. Peak assignments are preliminary, N.A. denotes "not assigned" 652

Figure II.1.B.41. Summary of XPS measurements on 50-nm a-Si / 10-nm SiO₂ films at varying states of lithiation and delithiation. Peak assignments are preliminary, N.A. denotes "not assigned" 653

Figure II.1.B.42. The voltage profiles of LiFePO₄/Si cells containing the 500-nm Si thin-film model electrodes (1st, 2nd, 5th, and 10th cycle) with (a) 1.2 M LiPF6 EC:EMC (3:7 wt%), (b) 1.2 M... 655

Figure II.1.B.43. Cycling performance and efficiency of LiFePO₄/Si cells containing the 500-nm Si thin-film model electrodes with different electrolyte solutions 656

Figure II.1.B.44. Schematic of the procedure to estimate the actual state of charge (SOC) of silicon electrodes. From (a) the GITT profile, (b) the relation between quasi-open-circuit voltage... 657

Figure II.1.B.45. The calculated capacity loss from electrolyte decomposition and lithium trapping in LiFePO₄/Si cells containing the 500-nm Si thin-film model electrodes with different... 657

Figure II.1.B.46. Schematics of the gradient polarity solvent wash technique 658

Figure II.1.B.47. Gradient polarity solvent wash was applied to a Cu electrode polarized to 10 mV Li/Li+ 659

Figure II.1.B.48. Three different scanning rates of CV at 1, 10, and 60 mV min-1 were applied to the Cu electrodes, respectively, with baseline electrolyte and two additives-based electrolytes.... 659

Figure II.1.B.49. Cyclic voltammograms of a-Si thin-film anodes cycled in various electrolytes between 1.5 V and 50 mV vs. Li/Li+ at a scan rate of 0.1 mV/s showing the (a) first and (b) sixth cycles 660

Figure II.1.B.50. Summary of the parasitic current density during the galvanostatic cycling (GC) - chronoamperometry (CA) test for a-Si cycled in various electrolytes. During the formation cycle,... 661

Figure II.1.B.51. Variation of normalized discharge/lithiation capacity with cycle number (up to 110 cycles) of the a-Si anodes using multiple electrolytes at a 1C equivalent current density.... 662

Figure II.1.B.52. SEM micrographs of the a-Si anodes after 110 cycles 662

Figure II.1.B.53. Elemental analysis of the a-Si anodes after five cycles and after 110 cycles using EDX. Error bar indicates the standard deviation of three measurements on three different... 663

Figure II.1.B.54. Electrochemical results of 319 cycles on native SiOx-terminated Si wafer. Panel (a) shows potential vs. time for periodic cycles, with 0.2 V incremental offset, whereas (b)... 664

Figure II.1.B.55. STEM HAADF image and EELS areal density maps for a FIB-prepared cross section of SEI formed on Si wafer after 50 cycles. C K, Si L, O K, Li K, and F K EELS areal density... 665

Figure II.1.B.56. SIMS depth profiles on formed SEI after 1 cycle (left) and 319 cycles (right). All series are normalized to their maximum intensity 666

Figure II.1.B.57. Changes in the current density over time during the potentiostatic hold at 1.0, 0.5, 0.2, and 0.01 V (vs. Li/Li+) in Gen2 (left) and Gen2 + H₂O50ppm (right). Corresponding... 667

Figure II.1.B.58. Roughness, thickness, and resistivity of the SiEI measured with AFM and SSRM. Mean results are plotted and the standard deviations are shown as error bars. Schematic... 668

Figure II.1.B.59. XPS spectra of the SiEI layers formed in Gen2 (top) and Gen2+H₂O50ppm (bottom) at 1.0, 0.5, 0.2, and 0.01 V as indicated in the figure. Si 2p, O 1s, C 1s, F 1s, P 2p, and... 669

Figure II.1.B.60. ATR-FTIR spectra of the SiEI layers formed in Gen2 and Gen2+H₂O50ppm at 1.0, 0.5, 0.2, and 0.01 V 670

Figure II.1.B.61. Gas chromatograms of electrolytes recovered from the cells after the potentiostatic holds (left) and the chemical equations of the LiPF6 hydrolysis reaction (right) 670

Figure II.1.B.62. High-resolution elemental maps of SiEI layers formed at 0.2 V (left) and 0.5 V (right) in Gen2 (top) and Gen2+H₂O50ppm (bottom). The intensity is on a blue-to-red color... 671

Figure II.1.B.63. (a) Cycling performances and Columbic efficiencies of Si/C-P and Si/C-S electrodes at C/10, from 1.00 V to 0.01 V; (b) Galvanostatic discharge/charge profiles of Si/C-P... 673

Figure II.1.B.64. Three representative solvation structures in Gen2 electrolyte: (a) solvent-separated ion pairs (SSIP), (b) contact ion pairs (CIP), and (c) aggregates (AGG). The light blue,... 674

Figure II.1.B.65. The proportions of SSIP, CIP, and AGG in (a) the EC electrolyte and (b) the Gen2 electrolyte 675

Figure II.1.B.66. The coordination number of solvent molecules for SSIP, CIP, and AGG species in (a) EC electrolyte and (b) Gen2 electrolyte 675

Figure II.1.B.67. AGG species in the Gen2 electrolyte 676

Figure II.1.B.68. The proportions for SSIP, CIP, and AGG in (a) the ECF electrolyte and (b) the GenF electrolyte 677

Figure II.1.B.69. The coordination number of solvent molecules for SSIP, CIP and AGG species in a) ECF electrolyte and b) GenF electrolyte 677

Figure II.1.B.70. Variation of normalized discharge capacity with cycle number (up to 110 cycles) of the a-Si anodes using multiple electrolytes at a 1 C equivalent current density 679

Figure II.1.B.71. SEM micrograph of the a-Si anodes after 110 cycles 679

Figure II.1.B.72. Elemental analysis of the a-Si anodes after 5 cycles and after 110 cycles. Error bars indicate the standard deviations of the three measures on three different locations of each sample 680

Figure II.1.B.73. Synthesis of LMC 681

Figure II.1.B.74. FTIR data collected for LMC 681

Figure II.1.B.75. Synthesis of LMC 681

Figure II.1.B.76. Synthesis of LEDC 682

Figure II.1.B.77. FTIR spectra of the synthesized LEDC, stirred under CO₂ for 1 day (blue curve) and 7 days (red curve) 682

Figure II.1.B.78. NMR spectra of LEDC compounds under various conditions 682

Figure II.1.B.79. Left: Current density study for 5-10 Ωㆍcm resistivity Si wafers in the ATR-FTIR spectroelectrochemical cell. A voltage drop of ~300 mV is caused by poor contact to the Si wafer.... 683

Figure II.1.B.80. Left: Current density study for 5-10 Ωㆍcm resistivity Si wafers in the ATR-FTIR spectroelectrochemical cell. A voltage drop of ~300 mV is caused by the resistivity of the low... 684

Figure II.1.B.81. Cyclic voltammograms for heavily surfaced p+-doped Si wafers (bulk resistivity 5-10 Ωㆍcm) in the ATR-FTIR spectroelectrochemical cell. These surface-doped wafers feature... 684

Figure II.1.B.82. Chronoamperograms of silicon wafers with native oxide (left, SiOx) and hydrogen terminated (right, SiH) at 400 and 150 mV vs. Li/Li+ (gray and blue, respectively). The wafers... 685

Figure II.1.B.83. Carbonyl region of FTIR spectra corresponding to the chronoamperograms shown in Figure II.1.B.82, showing loss of uncoordinated (uc) EMC relative to other electrolyte... 686

Figure II.1.B.84. Galvanostatic cycling voltage profiles and corresponding in situ Raman spectra collected at specific voltages: (a) the 1st cycle and (b) the 2nd cycle. The spectra were obtained... 688

Figure II.1.B.85. Schematic (a), scattering orientation (b), and photo (c) of the in situ electrochemical cell 690

Figure II.1.B.86. Neutron reflectivity curves (open circles) and fits (grey line) for PAA on a-Si thin film anode at different 691

Figure II.1.B.87. The resulting SLD plots from reflectivity fitting routine representing a one-dimensional view of the film heterostructures separated by interfacial roughness 691

Figure II.1.B.88. A summary of the SLD (left) and thickness (right) values obtained from NR refinements 692

Figure II.1.B.89. Neutron reflectivity data with open holes representing collected data and the fit, shown as a solid line (top). The SLD profile from resulting fit (bottom) 694

Figure II.1.B.90. Schematic of the SEI chemistry with various binders (top) and a schematic representation of the relative fraction of inorganic versus organic SEI components (bottom) 697

Figure II.1.B.91. Headspace Solid-Phase Microextraction Gas Chromatography Mass Spectrometry (HS-SPME GC-MS)prevents injection of LiPF6 salt into the gas chromatographer while still... 698

Figure II.1.B.92. (a) Electrochemical performance of coin-type cells (with Si wafer vs. Li metal): Half of the samples were rested at OCV, while the other half were galvanostatically cycled... 699

Figure II.1.B.93. (top) Comparison of GC-MS gas chromatographs of the recovered electrolyte from potentiostatic holds at 1, 0.5, and 0.2 V for 10 hrs. (bottom) Reaction mechanism for some... 700

Figure II.1.B.94. Comparison of GC-MS gas chromatographs of pristine Gen2 electrolyte and the electrolyte from a half-cell containing silicon, lithium, and Gen2 held at 60℃ 700

Figure II.1.B.95. (a) Cycle data for d = 30 nm SiHx-terminated (black) and dodecyl-terminated (blue) in a half-cell configuration. The first three cycles are at a C-rate of C/20, and the latter 13... 702

Figure II.1.B.96. SEM images of milled silicon powders 703

Figure II.1.B.97. Zeta potential of Deep Dive silicon (left) and milled silicon powders (right) 703

Figure II.1.B.98. Representative cycling data measured for milled silicon electrodes 704

Figure II.1.C.1. (a) Cycling performances and Columbic efficiencies of Si/C-P and Si/C-S electrodes at C/10, from 1.00V to 0.01V; (b) Galvanostatic discharge/charge profiles of Si/C-P electrode... 713

Figure II.1.C.2. Schematics of the gradient polarity solvent wash technique 714

Figure II.1.C.3. Gradient polarity solvent wash was applied to a Cu electrode polarized to 10 mV Li/Li+ 714

Figure II.1.C.4. Three different scanning rates of CV at 1, 10 and 60 mV min-1 were applied to the Cu electrodes respectively with baseline electrolyte and two additives-based electrolytes.... 715

Figure II.1.D.1. (a) Cycling performance of NMC532 || Si/Gr (CAMP electrodes) in BTFE-based electrolytes with different salt concentrations; (b) cycling performance of NMC532 || Si/Gr... 718

Figure II.1.D.2. (a) Cycling performance of NMC532 || Si/Gr (CAMP electrodes) in BTFE-based electrolytes with different salt concentrations at 0.05C and 0.33C; (b) high voltage stability... 719

Figure II.1.D.3. Photographs of ignition tests of glass fibers saturated with E-control-3 (a) and NFE-2 LHCE. (c) Long-term cycling performance and Coulombic efficiency of Li||Si/Gr half cells... 721

Figure II.1.D.4. Electrochemical behavior of Si/Gr||NMC333 full cells in different electrolytes. (a) Long-term cycling performance of Si/Gr||NMC333 full cells with different electrolytes at 25℃.... 722

Figure II.1.E.1. Schematic illustration of the prelithiation of Si electrode film 725

Figure II.1.E.2. The effects of pressure and pressing duration on ICE of Si anode-based half cell 726

Figure II.1.E.3. Morphology evolution of Si anode before (a,c,e) and after (b,d,f) prelithiation treatment. (a,b) TEM images, (c,d) in-plane and (e,f) cross-section SEM characterization of Si anode 727

Figure II.1.E.4. (a) First cycle voltage curves and (b) cycling stability of Si-LiFePO₄ and LixSi-LiFePO₄ full cells operated between 2.5 and 3.8 V 728

Figure II.2.A.1. Standard diagnostics protocol 731

Figure II.2.A.2. (Left) Galvanostatic first-cycles capacities (without a potentiostatic hold on the discharge) and (right) sources of first-cycle capacity loss of the four cathodes examined 731

Figure II.2.A.3. (Left) Capacity vs. cycle number for the LCV (4.2-2.5 V) cycles and (right) the UCV (4.5-2.5 V) cycles used in the standard protocol. Cycles 4 and 10 were not included.... 732

Figure II.2.A.4. (Left) Capacities during the potentiostatic-hold cycle and (right) effect of the potentiostatic hold on discharge capacities, where discharge capacities from cycles 6 and 9 are used... 732

Figure II.2.A.5. Polarizations at various SOC as determined by current interrupts for cycles 4 (orange) and 10 (green) 733

Figure II.2.A.6. Average rate performance of the four cathodes surveyed. Discharge current (mA/g) is indicated in each 3-cycle subdivision, 20 mA/g used for all charge cycles 734

Figure II.2.A.7. Schematic of in situ MS set up for gas analysis using direct sampling method from pouch cell (left image) and for thermal stability test (right image) 734

Figure II.2.A.8. Gas generation during cycling with UCVs of 4.2 V (top left panel), 4.4 V (top right panel), and 4.6 V (bottom panel) 735

Figure II.2.A.9. O₂ (upper left) and CO₂ (upper right) generation rate during thermal stability test of composite electrode without the presence of electrolyte. Neutron diffraction of composite... 737

Figure II.2.A.10. O₂ and CO₂ generation rate during thermal stability test of composites with the presence of electrolyte 738

Figure II.2.A.11. DSC results of five samples with various amounts of electrode material and electrolyte 739

Figure II.2.A.12. ICP-MS quantification results. (a) Concentration of Mn (blue, circle), Ni (red, square) and Co (orange, diamond) from anodes cycled with various NMC cathodes. (b) Concentration... 740

Figure II.2.A.13. SICs of m/z detected via HPLC/ESI-MS that are present in the aged Gen2 electrolyte samples from the cycled pouch cells composed of graphite anodes against NMC-532(orange),... 740

Figure II.2.A.14. Concentrations of Mn, Co and Ni in solution from the cathode materials used in this study. The concentrations of the metals without the additive are given as blue bars; and with... 742

Figure II.2.A.15. Concentrations of the transition metals vs. various combinations of the ideal stoichiometries with bifluoride present. Markers represent the data, and dotted lines, the least... 743

Figure II.2.A.16. In situ ATR-FTIR cell design 743

Figure II.2.A.17. ATR-FTIR spectra showing the changes in peak intensities during electrochemical delithiation of NMC-622 cathode for electrolyte components-EMC, EC, and PF6-associated... 745

Figure II.2.A.18. ATR-FTIR and Raman spectra comparing the pristine and aged NMC-811 composite electrodes 745

Figure II.2.A.19. (Left) C/10galvanostaic cycle of an NMC-622 cathode (left), with dq/dV (inset). (Right) FTIR-ATR spectra 746

Figure II.2.A.20. ATR-FTIR spectra at OCV and after the 3rd galvanostatic charge/discharge cycles of NMC-622. After cycling, new peaks emerge that indicate formation of CEI species,... 746

Figure II.2.A.21. Potential change during the 0.95 V potentiostatic hold in an oxide(+)/oxide(-) symmetric cell for a total of 300 h. (a) Full-cell and (b) electrode potentials. (c) Current flow... 748

Figure II.2.A.22. Current flow through an oxide(+)/oxide(-) symmetric cell during the first (left) and second (right) 100 h potentiostatic holds at 0.6 V (black), 0.8 V (blue), and 0.95 V (red) 748

Figure II.2.A.23. Nyquist plots (100 kHz - 0.01 Hz, 30℃, 0 V) for oxide(+)/oxide(-) symmetric cells after (a) 0 h, (b) 100 h and (c) 200 h at 0.6 V (black), 0.8V (blue) and 0.95 V (red). Mind... 749

Figure II.2.A.24. Nyquist plots (100 KHz-0.01 Hz, 0 V) for oxide(+)/oxide(-) symmetric cells comparing the effect of 0-0.8 V cycling at a C/15 rate vs. 0.8 V potentiostatic hold. Panel a is for... 750

Figure II.2.A.25. In situ formed additives 2a and 2b and their precursors 1a and 1b 750

Figure II.2.A.26. (A) Specific capacity per weight of lithiated oxide of NMC-622//Gr cells containing additives and the baseline electrolyte (black line) obtained for cycling at a rate of C/3 with... 751

Figure II.2.A.27. (A) Pictures of the Gen2 electrolytes with intentionally added 2 vol % water without and with 0.2 vol% TMSML stored at room temperature (25℃) original and after 1 day,... 752

Figure II.2.B.1. (a) Ternary phase diagram of high-Nickel NMCs including the Ni94Co6 composition (gray sphere), (b) SEM-images of Ni94Co6 particles showing a narrow particle size distribution,... 756

Figure II.2.B.2. (a) Initial voltage profiles and (b) magnified view of high-voltage region for the Ni94Co6. Cells used Li-metal anodes and were cycled at C/5 (1C=180mA/g) after 3 formation... 758

Figure II.2.B.3. (a) Illustration of concentration gradient materials using an in-house built, co-precipitation reactor for full- concentration gradient particles, (b) core-shell gradient particle,... 759

Figure II.2.B.4. SEM images of baseline, Ni-rich compositions annealed at different temperatures 760

Figure II.2.B.5. (a) and (b) SEM images, (c) and (d) STEM images of pristine NMC-333 and NMC-622 crystal samples, (e) indexed facets on platelet NMC particles and (f) XRD patterns... 761

Figure II.2.B.6. First 100-cycle charge-discharge profiles of (a, c) NMC333 and (b, d) NMC622 in the voltage window of (a, b) 3-4.3 V and (c, d) 3-4.6 V. e) and f) Comparison of discharge... 761

Figure II.2.B.7. HAADF STEM imaging shows facet-dependent surface reconstruction on (a, b) pristine NMC-333 and c, d) pristine NMC-622 particles. SRL was found on non-(001) surface... 762

Figure II.2.B.8. Atomic-resolution HAADF STEM images of SRL formation on: non-(001) surfaces (a and c) and (001) surfaces (b and d) of cycled NMC-333 (a and b) and NMC-622 (c and d)... 763

Figure II.2.B.9. Phase transitions at open surfaces, closed surfaces, and grain boundaries. (a) Cross-sectional SEM image of a secondary particle. (b) HAADF-STEM image of the NMC76, (c-d)... 764

Figure II.2.B.10. 6Li solid-state NMR analysis of pristine NiMn5050 and NMC-442 compositions 765

Figure II.2.B.11. Comparison of 6Li solid-state NMR analysis of cycled and pristine NiMn5050 and NMC-442 compositions 765

Figure II.2.B.12. Comparison of 6Li solid-state NMR analysis of pristine and cycled samples having different dopants 766

Figure II.2.B.13. Comparison of 6Li solid-state NMR of model systems: The effect of synthesis conditions and the presence of Co on Li/Mn ordering ('clustering') 767

Figure II.2.B.14. (a) Ni K-edge XANES for the LC-NMC compared to data from standard NMC compositions and NCA. (b) Corresponding magnitudes of the Fourier transformed EXAFS... 768

Figure II.2.B.15. (a) Rate data of the LC-NMC cathode conducted between 4.45-2.5V at 30℃. Charge and discharge currents were the same and are as listed in the plot (mA g-¹). (b) Ragone... 769

Figure II.2.C.1. Schematic representation of the slab model for NMC-111 (104) facet (top view): (a) stoichiometric amount of Co, (b) excess of one Co ion per surface, (c) excess of two Co... 772

Figure II.2.C.2. Lowest energy configuration of electrolyte components at or near the (012) facet of (a-d) fully lithiated or (e-f) fully delithiated NMC-532. (a) EMC, (b) EC, (c) HFDEC, (d) DFEC,... 774

Figure II.2.C.3. Projected Density of States (PDOS) on the TMs in fully lithiated (pristine) NMC. The dashed line indicates the Fermi level 775

Figure II.2.C.4. Li/Ni anti-site formation energy change with number of defects. The defects are located in the same Li layer forming a row of continuous defects 775

Figure II.2.C.5. Total energy of LiNi0.5Ni0.5O₂ for different ionic configurations within the transition metal layer. Grey represent Ni, purple represents Mn and green represents Li in the layer... 776

Figure II.2.C.6. Total energy of LiNi0.5Ni0.5O₂ for different ionic configurations within the transition metal layer. (a) Configurations sorted by energies and the number of TM-TM bonds... 777

Figure II.2.C.7. Total energy change of LiNi0.5Ni0.5O₂ for five different ionic configurations within the transition metal layer, as a function of Li-Ni defect exchange concentration 778

Figure II.2.D.1. (a) High resolution X-ray data on four LLS samples fired at different temperatures as noted in the figure. The inset shows a magnified view of the (003) peaks and the table shows... 781

Figure II.2.D.2. Refinements neutron powder diffraction data (ANSTO) showing (a) the weight fraction of C2/m and (b) % Li/Ni exchange as a function of secondary firing temperatures 782

Figure II.2.D.3. Electrochemical performance of samples fired at different temperatures: 925℃, 950℃, 975℃, and 1000℃. The current for all cycles was 20 mA/g. The first cycle activation... 783

Figure II.2.D.4. Representative DSC data (baseline-subtracted, mass- normalized) from each charged cathode sample, all charged to the same calculated lithium content after formation cycles 783

Figure II.2.D.5. Operando synchrotron XRD analysis of a Li/LT- LiCo0.85Al0.15O₂cell cycled between 4.2 - 3.5 V vs. Li at 15 mA/g: (a) changes to strong peaks (selected regions) and... 784

Figure II.2.D.6. (a) Capacity vs. cycle number for lithium cells with LT-LiCo1-xAlxO₂ electrodes (0≤x≤0.5), (b) rate performance data (0≤x≤0.3) 785

Figure II.2.E.1. In situ tracking of cationic ordering/disordering in LiNi0.7MnxCo0.3-xO₂ (0 ≤ x ≤ 0.3) during calcination at 850℃. (A) Schematic illustration of the experimental setup for in situ... 788

Figure II.2.E.2. Li/Ni mixing as a function of composition in the series of LiNi0.7MnxCo0.3-xO₂ (0≤x≤0.3) 789

Figure II.2.E.3. Dependence of cationic ordering and electrochemical performance in NMC71515 on sintering temperature and holding time. (A) Synchrotron XRD patterns from NMC71515... 790

Figure II.2.E.4. Schematic illustration of the approach with a "closed" loop for rational design of synthesis in making high-Ni 791

Figure II.2.E.5. In situ tracking of the structural evolution and formation of Li₂CO₃ in NMC71515 upon cooling during synthesis. a) Temperature-resolved in situ XRD patterns recorded during... 792

Figure II.2.F.1. Discharge capacity and coulombic efficiency of full-cells with SiO₂ electrode coating as a separator (a) and a sheet of polypropylene as a separator (b) 795

Figure II.2.F.2. SEM images of SiO₂ electrode coating and a sheet of polypropylene representative of the separator schemes used for cells in Figure II.2.F.1 795

Figure II.2.F.3. (a) TEM image and (b) XRD pattern of the Na 3 MnZr(PO 4) 3 cathode material prepared by the sol-gel method 796

Figure II.2.F.4. (a) Charge/discharge profiles of the Na 3 MnZr(PO 4) 3 cathode at different current densities. (b) Charge/discharge cycling performance of the Na 3 MnZr(PO 4) 3 cathode... 796

Figure II.2.F.5. The structure and characteristic of Li6PS5Cl sulfide solid electrolyte. (a) XRD. (b) The Nyquist plots at different temperatures. (c) Temperature dependence of the ionic conductivity.... 797

Figure II.2.F.6. (a) The structure of Li₂S/Li6PS5Cl/Li battery. (b-c) Electrochemical performance of Li₂S/Li6PS5Cl/Li battery at 25℃ and 55℃, respectively 797

Figure II.2.F.7. Structure and electrochemical performance of Na0.6(Li0.2Mn0.8)O₂ (a) XRD pattern. The inset is ordered Li/Mn atoms. (b) the P3 structure. (c) Charge and discharge profiles... 798

Figure II.2.F.8. (a) XPS patterns of Mn during the initial charge and discharge process. (b) Ex situ XRD patterns of P3-Na0.6(Li0.2Mn0.8)O₂ at different states 799

Figure II.2.G.1. Synthesis and electrochemistry of LMNOF baseline. (a) XRD pattern and Rietveld refinement of optimized cathode, (b) voltage profiles in cycle 1-20, dQ/dV curves for voltage... 801

Figure II.2.G.2. Synthesis and electrochemistry of LNTMOF baseline. (a) XRD pattern and Rietveld refinement of optimized cathode, (b) voltage profiles of the baseline in cycle 1-20, dQ/dV... 802

Figure II.2.G.3. Left: Cell resistance plotted against OCV for LNTMOF with and without carbon ball milling. Right: voltage profile during the 30-second pulse at an OCV close to 3.3 V 803

Figure II.2.G.4. SEM images and XRD patterns of a) L1.3M0.4NO, b) L1.3M0.5NOF, c) L1.2M0.4TO, and d) L1.2M0.6TOF samples. EDX mapping results on b) and d) are shown at the bottom 804

Figure II.2.G.5. a)-d) First 20-cycle voltage profile of L1.3M0.4NO, L1.3M0.5NOF, L1.2M0.4TO, and L1.2M0.6TOF half cells. e) and g) capacity retention of the half cells. f) and g) discharge... 804

Figure II.2.G.6. First-cycle incremental capacity (dQ/dV) profiles of: a) L1.3M0.4NO and L1.3M0.5NOF half cells and b) L1.2M0.4TO and L1.2M0.6TOF half cells. The current density is 10 mA/g 805

Figure II.2.G.7. Setup of the fluidized bed reactor (left) and XRD patterns of pristine LNTMO and the F- LNTMO at different conditions (right). The F content was determined by EDX analysis 805

Figure II.2.G.8. Summary of XPS depth-profiling experiments for pristine and F-LNTMO 806

Figure II.2.G.9. Electrochemical cycling for first few cycles for pristine LNTMO and 30min, 3hrs and 12hrs F-LNTMO 806

Figure II.2.H.1. 7Li (a, c) and 19F (b, d) spin echo NMR spectra of LMNOF (a, b, in black), LNTMOF (c, d, in black) and LiF (a-d, in blue) obtained at B0= 7 T and 60kHz (a, b) or 55kHz (c, d)... 809

Figure II.2.H.2. Raman spectra collected on a) LMNOF and b) LNTMOF. Schematics of the Mn-O symmetric stretch are also shown 810

Figure II.2.H.3. mRIXS results of Mn-L (a) and O-K (b) collected on LMNOF cycled to different electrochemical potentials. The red rectangular in (a) indicates the area that non-distorted Mn-L... 811

Figure II.2.H.4. a) Comparison of F K-edge XAS of pristine L1.3M0.5NOF and LiF, b) a schematic showing covalent and ionic bonding environment of F. Comparison of F K-edge XAS of L1.3M0.5NOF... 812

Figure II.2.H.5. a) DEMS measurements of O₂ and CO₂ evolution during cycling of LMNOF and b) fluoride-scavenging coupled with DEMS to examine fluoride dissolution from LMNOF.... 813

Figure II.2.H.6. Atomic structures of Li1.2Ti0.2Mn0.6O1.8F0.2. (a) As-captured atomic-scale HAADF STEM image and (b) corresponding Fast Fourier transform (FFT). (c) Filtered HAADF STEM... 814

Figure II.2.H.7. (a) Evolution of the amount of percolating Li as a function of F content obtained from Monte Carlo simulations at 1873 K, a temperature representative of typical synthesis... 815

Figure II.3.A.1. The electrochemical stability window of different electrolytes and the degradation of electrolytes on cathode surface as-revealed by theoretical modeling and experiments.... 819

Figure II.3.A.2. Structure characterization of PLD-grown NMC thin-films with different oxygen pressure. The SXRD (a) and XRR (b) of NMC thin-films grown at an oxygen pressure of 75mT,... 819

Figure II.3.A.3. The electrochemical characterization of PLD-derived NMC thin-films of different thickness. The cyclic voltammograms and potential-capacity curves of NMC thin-films grown... 820

Figure II.3.A.4. The evolution of interphase from the chemical reactions between NMC and carbonate electrolytes (1M LiPF6 in EC : DMC). The surface-sensitive total reflection X-ray absorption... 821

Figure II.3.B.1. a) Electrochemical response of Cu, Ni and Pt electrodes in 1 M LiPF6 in EC/EMC 3:7w. b) % of metal dissolution in each response as measured by ICP-MS. c) Schematic of the... 825

Figure II.3.B.2. Online Electrochemical Mass Spectrometry. a) Gas detection following linear potential sweep to 6 V of C-65 carbon electrode. Signals for HF, CO₂ and POF3 are clearly visible.... 826

Figure II.3.B.3. Rotating ring disk proton detection method. a) Cyclic voltammogram of hydrogen oxidation/evolution reaction in a H2 saturated electrolyte. b) Polarization curves for HOR at... 827

Figure II.3.B.4. Effects of anion, solvent, substrate and rotation rate on the electrolyte oxidation. a) Comparison of the electrochemical responses on Pt(111) electrode in LiClO4 and LiPF6 based... 828

Figure II.3.C.1. XRD pattern of as-synthesized Li4Mn2O5 with an SEM image shown in the inset 831

Figure II.3.C.2. Upper left: charge and discharge profiles of Li4Mn2O5 in a lithium half cell when cycled between 4.8-1.2V and (lower left) capacity as a function of cycle number. Upper right:... 832

Figure II.3.C.3. Left: X-ray Raman Mn L-edge spectra on pristine and charged Li4Mn2O5 electrodes as a function of charging potential. Right: X-ray Raman O K-edge spectra 833

Figure II.3.C.4. Left: XRD pattern of Li2Ru0.75Sn0.25O3 with its structure and the particle morphology indicated in the insets. Right: XRD pattern of Li2Ru0.75Ti0.25O3 833

Figure II.3.C.5. Upper left: Voltage profiles of a Li/Li2Ru0.75Sn0.25O3 cell cycled between 4.6 and 2.0V. Upper middle capacity as a function of cycle number. Bottom left : cyclic voltammogram... 834

Figure II.3.D.1. Morphology and phase characterization of polycrystalline and single crystalline NMC76. (a, b) SEM images of polycrystalline and single crystalline NMC76. (c, d) Cross section... 838

Figure II.3.D.2. (a) Cross section images of polycrystalline NMC76 cathodes with different mass loadings. (b) Cross section images of single crystalline NMC76 cathode with different mass... 839

Figure II.3.D.3. (a) Frist charge and discharge curve of single cyrstal NMC76 in a graphite/NMC76 full cell between 2.7 and 4.4 V at 0.1C (1C = 200 mA/g). (b) Cycling stability of single cyrstal... 839

Figure II.3.D.4. (a) Cyclic voltammetry curve of polycrystalline NMC76 under in situ AFM testing, inserted figure is the demonstration of in situ AFM experimental setup. (b, c, d, e, f, g, h and i)... 840

Figure II.3.E.1. (a) PMpipFSI/LiFSI electrolyte conductivity dependence on temperature measured by electrochemical impedance spectroscopy, and (b) Raman spectra (600-1500 cm-1) for... 843

Figure II.3.E.2. (a-d) Pairwise radial distribution functions g(r) computed from MD simulations.3-4 (Strong spatial coordination between Li+ and FSI- within 5Å can be observed. In contrast,... 844

Figure II.3.E.3. Cyclic voltammograms of (a) 1 M LiFSI-PMpipFSI, (b) 5 M LiFSI-PMpipFSI and (c) Gen 2 electrolyte using Al working electrode in an Al-coated 2032-coin cell setup (Figure II.3.E.1b).... 845

Figure II.3.E.4. (a) Cyclic voltammograms of ILEs scanned to 6.0 V vs Li+/Li and (b) scanned to 5.0 V vs Li+/Li using Pt as working electrode and Li as counter and reference electrode;... 846

Figure II.3.E.5. C-rate capability of NMC532/Li cells with 1 M and 5 M LiFSI-PMpipFSI electrolyte cycled between (a) 4.3-3.0 V, and (b) 4.7-3.0 V; snapshots randomly selected from equilibrated... 847

Figure II.3.F.1. Schematic representation of a scanning electrochemical microscope (SECM) 850

Figure II.3.F.2. Schematic Representation of the Polymer Assisted Deposition (PAD) Process 851

Figure II.3.F.3. (A) Photograph of PAD films coated on~1cm² silicon samples, (B) XRD for LMO deposited on Si substrates (C) AFM of PAD LMO films on Si 852

Figure II.3.F.4. (A) XRD for LMO PAD film on stainless steel (B) Cyclic Voltammetry for PAD Film on stainless steel (C) XRD of LMO(111) deposited via PAD on STO (111) 852

Figure II.3.F.5. Cyclic Voltammetry for a 2 mm Pt disk electrode in 1M LiClO4:PC, with 1mM Mn(II) and Mn(III) acac 854

Figure II.3.F.6. SECM Tip Voltammetry collected at a 25 µm tip electrode placed near an LMO substrate. Data was collected following 30-minute intervals of holding the LMO substrate at 4.5V vs Li/Li+ 855

Figure II.3.G.1. Calibration curve of Keyence contact sensors in the 0 - 1 mm range (left). Custom device configuration to measure thickness changes in 200 mAh cells (right) 859

Figure II.3.G.2. Thickness changes of NMC532 cells as a function of electrolyte, with the baseline hydrocarbon (left) and HFE/FEC electrolyte (middle). Electrochemical performance of NMC532... 859

Figure II.3.G.3. Prototype setup of the non-contact thickness measurement system (left) and laser position calibration (middle). The pixels from the laser is tracker using the ImageJ software... 860

Figure II.3.G.4. Dissolved Co concentrations in tested LCO cells as a function of time (200 cycles), voltage (4.5 and 4.6V), and electrolyte (EC/EMC, HFE, HFE/FEC) 861

Figure II.3.G.5. Dissolved metals concentration (Ni, Mn, Co) in tested NMC532 and NMC622 cells as a function of time (200 cycles), voltage (4.2 and 4.5V), and electrolyte (EC/EMC, HFE, HFE/FEC) 861

Figure II.3.G.6. Dissolved metals (Ni, Mn, Co) in tested NMC532 cells at 4.6V (left). NMC532 and NMC622 cells with the HFE electrolyte at 4.6V (middle). Stoichiometric ratios of HFE cells at 4.6V... 862

Figure II.3.G.7. Powder X-ray diffraction patterns for LCO and all NMC cathodes studied to date. LCO ( black), NMC111 ( red), NMC532 ( blue), NMC622 ( teal), and NMC811 ( violet) are depicted 863

Figure II.3.G.8. Custom gas manifold control plate (left) is comprised of a series of needle and ball valves, and monitored using the digital pressure gauge (± .1 torr). A typical sample cylinder... 863

Figure II.3.G.9. Cross sections of 50 nm (far and middle-left) and 100 nm (middle and far-right) following Pt deposition and FIB milling 864

Figure II.4.A.1. Reactive spray technology system set up and optimized at ANL to produce cathode material 868

Figure II.4.A.2. (a) XRD patterns and (b) SEM pictures of the layered NCM811 by RST. (e) Formation and cycle life testing plots for NCM811 electrodes made with active material synthesized... 868

Figure II.4.A.3. NCM 811 produced by FSP with different precursor and flame conditions. XRD pattern and SEM (a) and (b) nitrate precursors, (c) and (d) nitrate precursors with excess Li, (e)... 870

Figure II.4.A.4. (a) Different milling and sieving conditions used to post process NCM811 powder. (b) XRD pattern of NCM811 (a) as prepared, milled for (b) 1 and (c) 3 hours. Crystallite size... 870

Figure II.4.A.5. Half-cell data for electrode made with NCM811 by FSP using nitrate precursors. (a) Formation data for large scale sample (〉350g per batch), (b) Cycling data for sample at... 871

Figure II.4.A.6. Scanning electron micrographs of NCM 811 coated with 1wt% nano NCM111, (a) before and (b) after thermal treatment. Dark and light patches on particle surface may indicate... 871

Figure II.4.B.1. Initial charge-discharge profile of different LNMO samples with 3 mAh/cm2 loading thick electrode 874

Figure II.4.B.2. Galvanostatic cycling (left) and associated Coulombic efficiencies (right) for industry-partner LNMO with different novel electrolytes in half cells 875

Figure II.4.B.3. Charge-discharge profiles (Left) and cycle performances at C/3 (Right) of the LNMO samples synthesized with different excess lithium in the reaction mixture 875

Figure II.4.B.4. SEM images of the LNMO-3 and LNMO-5 samples and the corresponding electrochemical performances in half cells 876

Figure II.4.B.5. Cycling results for LNMO-graphite full cells cycled within a confined (green) and expanded (blue) voltage window 876

Figure II.4.B.6. Cycling results for LNMO-graphite full cells with 3 mAh/cm² loading and Gen2 electrolyte 877

Figure II.4.B.7. STEM/HAADF images of the (a) pristine LNMO and (b) LNMO after 225 cycles in Gen2 electrolyte. (c, d) Spatially resolved EELS spectra from the surface to the bulk of the cycled... 877

Figure II.4.B.8. Performance metrics per cycle at C/3 in terms of coulombic efficiency, energy efficiency, and energy and capacity on charge and discharge of LNMO/graphite cells with different... 879

Figure II.4.B.9. (a) cross-section SEM image of dry coated LNMO thick electrode with Haldor Topsoe material. (b) EDX mapping of the cross-section of the electrode. (c) voltage profile of formulation... 880

Figure II.4.B.10. (a) 1st cycle voltage profile of the LNMO/graphite full cell using formulation #3 cathode and dry coated graphite with capacity matching. Cycling performance of this full cell in terms... 881

Figure II.4.B.11. (a) OCV of half cells with Gen2 stored at room temperature (black) and at 55℃ (red). (b) OCV of half cells with Gen2 (red) and Daikin electrolyte (blue) as a function of the rest... 881

Figure II.4.C.1. (A) Sol Gel method for preparation of NFA cathode powders, (B - C) Scanning electron micrographs of the sol- gel synthesized NFA cathode powders, (D) EDS spectra of the sol-gel... 884

Figure II.4.C.2. Crystallographic assessment of the NFA compositional variants (A) X-Ray diffractograms, (B) Mossbauer spectra, (C) Schematic representation of the crystal structure of NFA... 885

Figure II.4.C.3. Electrochemical assessment of the NFA compositional variants (A) Cyclic voltammograms, (B) Charge/Discharge curves, (C) Cycling performance 886

Figure II.4.C.4. (A) Schematic representation of the co-precipitation process for the scale-up of the NFA class, (B) Scanning electron micrographs of the NFA cathode powders synthesized using... 887

Figure II.4.D.1. Characterizations of the pristine Mg/Ti-LNO material. (a) Ni/Ti L-edge and O K-edge soft XAS spectra, the represents carbonate species; (b) neutron diffraction and Rietveld... 892

Figure II.4.D.2. Electrochemical performance of the half cells containing the Mg/Ti-LNO cathode at 22℃ within 2.5°4.4 V. (a) The voltage profiles of the LNO and Mg/Ti-LNO at C/10 (20mA/g),... 893

Figure II.4.D.3. STEM-EDS tomographic reconstruction of the primary cathode particles with Gen-2 chemistry. Surface dopant is shown in red, bulk dopant is shown in blue, and Ni is shown in green 894

Figure II.4.D.4. (a) Atomic-resolution HAADF-STEM image of pristine VT Gen-3 Sb-doped LNO and (b) Sb distribution in VT Gen-3 Sb-doped LNO 894

Figure II.4.D.5. In situ probing structural degradation of delithiated LNO during oxygen loss. (a) Atomic-resolution TEM image of delithiated LNO. The insets shows FFT and enlarged image... 895

Figure II.4.D.6. (a) 3D electron tomography of a delithiated LNO particle at room temperature. (b) 3D electron tomography of the delithiated LNO with severe oxygen loss after in situ heating... 895

Figure II.4.D.7. (a) HAADF-STEM image and (b) Bright-field image of a delithiated TiMg-doped LNO after in situ heating at 250 for 1 h. (c) Atomic-resolution TEM image of the delithiated TiMg... 896

Figure II.4.D.8. (a) The relative surface oxygen release energies of doped LiNiO 2 with respect to the pristine phase. An orange color indicates an improved oxygen retention, while a purple... 896

Figure II.4.D.9. Battery performances of Gr||NMC811 coin cells using different electrolytes between 2.5 and 4.4 V. (a) Voltage profiles of the first formation cycle at C/20 and 25℃. (b-c)... 897

Figure II.4.D.10. Cycling performance of Gr||NMC811 coin cells with five different electrolytes. The Gr||NMC811 cells were subjected to two formation cycles at C/20 and then cycling at C/2... 898

Figure II.4.D.11. Discharge voltage profiles of the Project Progress Cells (PPC) at different currents and at room temperature 898

Figure II.4.D.12. Charge and discharge capacity of the Project Progress Cells (PPC) during cycling at room temperature 899

Figure II.4.E.1. SEM images of various low-cobalt or cobalt-free, high-nickel compositions prepared through metal hydroxide co-precipitation, i.e., NCM-900505 (LiNi0.9Co0.05Mn0.05O₂),... 903

Figure II.4.E.2. Pouch cell cycling performances of NCMAM-9004040101, NCA-900505, and NMA-900505 (voltage window 2.5 - 4.2 V; active material loading: 2.0 mAh cm-²; single stack) 903

Figure II.4.E.3. SEM images of LiNi0.85Co0.05Mn0.075Al0.02Mg0.005O₂ prepared through metal co-precipitation, which has been delivered to Tesla, Inc. for making thirty 2 Ah pouch cells... 903

Figure II.4.E.4. Coin cell performances of LiNi0.85Co0.05Mn0.075Al0.02Mg0.005O₂ (Ni-85): (left) coin-cell performance evaluation of samples from varying 200g batches; (right) pouch-cell... 904

Figure II.4.E.5. Preliminary cycling performances of Ta5+-doped LiNiO₂ in both coin and pouch cells 904

Figure II.4.E.6. Cyclability of graphite|LiNi0.94Co0.06O₂ pouch cells in LiFSI/EMC-based electrolyte with lithium difluoro(oxalato)borate (LiDFOB) as the SEI-forming additive 905

Figure II.4.E.7. Cycling performances in coin cells of LiNi0.94Co0.06O₂ treated with various ALD coating cycles 905

Figure II.4.E.8. Electrode thickness as a function of Ink flow rate. Web rate was held at 0.7 m/min 905

Figure II.4.E.9. Roll of NC-9604 on an 8-inch-wide Al foil. 10 x 10 cm wide defect free electrodes were punched out of the roll 906

Figure II.4.F.1. Schematic of the technical approach for creating high-performance LNMTO Li-ion cathodes 909

Figure II.4.F.2. Key unit operations and process variables for the solid-state synthesis of high voltage spinel cathode powders 909

Figure II.4.F.3. Charge/Discharge-voltage profiles and cycle performance for coin-type half-cells at 25℃ made with LNMTO cathodes from different production size batches, 20g, 200g, and... 910

Figure II.4.F.4. Charge/Discharge-voltage profiles and cycle performance for coin-type half-cells at 25℃ with LNMTO cathodes made with baseline and modified solid-state processes. Electrolyte... 910

Figure II.4.F.5. Charge/Discharge-voltage profiles and cycle performance coin-type half-cells made with LNMO and LNMTO cathodes synthesized using solid-state (SS) and co-precipitation (CP)... 911

Figure II.4.F.6. Comparison of the cycle performance of half-cell and full-cells made with baseline solid-state (SS) LNMTO cathode and preliminary core/shell LNMTO cathode. Anode: Li (half)... 911

Figure II.4.F.7. Cycle performance of coin-type full-cells and single-layer pouch cells at 25℃ made with the baseline LNMTO cathode with LiPAA binder, Electrolyte 1 M LiPF6 in 1:1 wt. EC/EMC... 912

Figure II.4.F.8. Charge/Discharge-voltage profiles and cycle performance of SLPC with baseline LNMTO cathode with LiPAA binder, Electrolyte 1 M LiPF6 in 1:1 wt. EC/EMC (with additive) and... 912

Figure II.4.G.1. XRD patterns of LiNi0.83Co0.11Mn0.06O₂ materials calcined at 480℃ first, and then at various high temperatures from 725℃ to 800℃ 915

Figure II.4.G.2. SEM images of as-synthesized LiNi0.83Co0.11Mn0.06O₂ material at 700℃ (a and b) and 800℃ (c and d) 916

Figure II.4.G.3. a) Capacity retention of LiNi0.83Co0.11Mn0.06O₂ synthesized at various temperatures. b) Capacity retention of LFP-coated LiNi0.83Co0.11Mn0.06O₂ with different LFP amount 917

Figure II.4.G.4. Capacity retention of the LFP-coated NCM/Graphite full-cells during 1 C cycling at room temperature and 40oC 917

Figure II.4.G.5. (a) HAADF-STEM image of LFP-NCM and (b-f) corresponding EDX elemental maps 917

Figure II.4.G.6. Image of twenty cells to be delivered to Idaho National Laboratory 918

Figure II.4.G.7. C-rate performance of Cells #1 and #2 919

Figure II.4.G.8. a) Charge/discharge curves b) capacity retention and coulombic efficiency of the low-cobalt material LiNi0.92Co0.055Mn0.025O₂ synthesized at 715℃ 919

Figure II.4.G.9. XRD patterns of various Mo content in LiNi0.5-x/2Mn0.5-x/2MoxO₂ (where x= 0, 0.01, 0.03, 0.05) 920

Figure II.4.G.10. Charge and discharge curves at different cycles in the voltage range between 2.0-4.5 V at current density of 20mA/g for (a) Undoped LNMO and (b) Mo-doped LNMO 921

Figure II.4.G.11. TEM images, STEM images and corresponding EDS maps of (a, b) LiNi0.5Mn0.5O₂ and (c, d) LiNi0.4995Mn0.4995O₂ 921

Figure II.4.G.12. HAADF-STEM and EELS analysis of Mo doped and undoped LiNi0.5Mn0.5O₂ 922

Figure II.4.G.13. STEM-HAADF images of LiNi0.5Mn0.5O₂ (a) before and (b) after cycling. STEM-HAADF images of Mo-doped LiNi0.5Mn0.5O₂ (e) before and (f) after cycling 922

Figure II.4.G.14. Electrochemical performance of LNMO with 0 - 1 at% Mo substitution showing: (a) Galvanostatic charge/discharge curves collected during the first cycle and (b) capacity stability... 923

Figure II.4.G.15. Rate capabilities of LNMO with 0 - 1 at% Mo substitution when cycled between 2.0 - 4.5 V vs. Li/Li + at specific currents of 10 - 200 mA/g 923

Figure II.4.G.16. Atomic structures of pristine undoped and Mo-doped LNMO. (a) HAADF STEM image of a near-surface region in undoped LNMO. (b) Magnified HAADF STEM image of undoped... 924

Figure II.4.G.17. Morphology, composition, and atomic structures of cycled undoped and Mo-doped LNMO particles. (a) STEM image and corresponding EDS elemental maps of an undoped LNMO... 925

Figure II.5.A.1. (a) S K-edge XANES spectra of LPS mixed with NCM333, 523, 811 and 811 coated with LiNbO3, (b) 1st cycle charge and discharge profile of NCM333 and NCM811 cathode.... 929

Figure II.5.A.2. Optical images (a) and UV-vis absorbance spectra (b) of and PVdF co-block polymer (65% PEO, 82% PEO) binder in 0.05 mmol/L polysulfide solution in DOL/DME 930

Figure II.5.A.3. Discharge capacity and coulombic efficiency at 0.2 C (a), and discharge/charge voltage profiles at 0.05 C of sulfur composite cathodes with PVdF and co-block polymer binder.... 930

Figure II.5.A.4. Raman spectrum of pristine LiPF6 salt collected with a 400 nm laser wavelength in (i) CW, (ii) Kerr gated mode, (iii) baseline correction of Kerr gated spectrum. The intensity... 931

Figure II.5.B.1. Optimized structure and bond length of TPQD obtained by DFT calculation (grey denotes to the carbon, yellow for sulfur and red for oxygen) 936

Figure II.5.B.2. O K-edge XANES spectra of TPQD electrodes at the different states of charge 936

Figure II.5.B.3. (b) S-K edge XAS spectra of TPQD electrodes at different state of charge. (c) The structural evolution of TPQD electrodes during the lithiation process 937

Figure II.5.B.4. Digital photograph for sulfur cathode obtained from the cycled pouch cell (schematic illustration) with indicating boxes for three selected spots of interest; outer region nearby... 938

Figure II.5.B.5. Spatially-resolved XAS and XRF imaging for cycled Li metal anode (inner side) 939

Figure II.5.C.1. (a). SEM images taken at different magnifications. (b). Rietveld refinement of the XRD pattern of LR-NCM. (c). The discharge capacity and energy density of the modified LR-NCM... 943

Figure II.5.C.2. (a). Voltage profiles and (b). cycling performance of the LR-NCM cycled in standard electrolyte. (c). Voltage profiles and (d). cycling performance of the LR-NCM cycled in 2%... 944

Figure II.5.C.3. Cryo-TEM images of the (a). cycled LR-NCM in the Baseline electrolyte and (b). in 2% LiBOB electrolyte. (c). XPS spectra of the pristine and cycled LR-NCM 945

Figure II.5.C.4. STEM/HAADF images of the (a). cycled LR-NCM in the Baseline electrolyte and (b). cycled LR-NCM in 2% LiBOB electrolyte. Spatially resolved EELS spectra from the surface... 946

Figure II.5.C.5. Electrochemical performance of the (a). initially cycled LR- NCM and (c). initially cycled NMC811 with or without heat treatment. The changes in the occupancy of Li in TM layer... 947

Figure II.5.C.6. (a-c), results for HCE. (e-g), results for CCE. (a, e), Inactive Li morphology at low magnifications for both electrolytes. (b, f), HRTEM shows that a different amount of metallic... 948

Figure II.5.D.1. Spatial and temporal evolution of structural degradation from the surface into the bulk STEM-HAADF images of the Li1.2Mn0.6Ni0.2O₂ cathode show the gradual propagation... 951

Figure II.5.D.2. Atomic-resolution TEM of electrochemically deposited Li metal (EDLi) and SEI interface. (a) Bright-field TEM image of the EDLi at a low magnification. (b) Atomic-resolution image... 953

Figure II.5.E.1. Design of 3-omega thermal sensors and how they are incorporated into an electrochemical battery pouch cell for in-operando measurements. (A) Sensor and sample design and... 956

Figure II.5.E.2. Results of operando measurements. (A) Thermal contact resistance (TCR) between separator and electrodes as a function of pouch age during formation cycling. (B) Representative... 957

Figure II.5.F.1. Change in stress-thickness vs. time for respective cycles from the MOSS studies. Left plot is the response with soft (PEO) artificial layer. Right plot is the response with stiff (LiF)... 960

Figure II.5.F.2. Delamination of PAA oligomers by (a) breaking all Li- O bonds, (b) breaking all Li-Li bonds, and (c) breaking mixed Li-O and Li-Li bonds. (d) The work of separation in terms... 961

Figure II.5.F.3. The microstructure of mossy Li on the stripping side under different pressures: (a) 0.05 MPa, (b) 0.11 MPa, and (c) 0.17 MPa. The current density is 1 mA/cm2 and the areal... 961

Figure II.5.F.4. (a) EIS curves for the three pressures of 0.23, 0.35, and 0.61 MPa. (b) EIS results 962

Figure II.5.F.5. The microstructure of mossy Li electroplated at different current densities in the DOL-DME electrolyte 962

Figure II.5.F.6. The reaction mechanism of lithium surface treatment with chlorosilanes and simulation results of intermolecular interaction in resulted siloxane coating film on lithium surface 963

Figure II.5.F.7. Galvanostatic cycling voltage profiles for symmetric cells using coated (TMCS or PhDMCS modified) or uncoated lithium electrodes under (a) low (0.25 mA/cm2, 1 mAh/cm2)... 963

Figure II.5.F.8. In situ characterization of symmetric cells using PhDMCS treated or untreated lithium electrodes. (a) and (b): Impedance before and during cell cycling. (c) and (d): Height... 964

Figure II.5.G.1. Conductivity of Li+- neutralized sulfonated PSf-co-PEO polymer solutions with added LiTFSI salt. Polymer concentration is reported as sulfonate concentration 967

Figure II.5.G.2. Conductivity and viscosity of a range of potential additives to improve conductivity of the control 0.1 M polymer in 2:1 (vol.) EC:DMC. Each additive is introduced at 0.1 M... 968

Figure II.5.G.3. Second charge and discharge curves at C/20 for batteries fabricated with the 0.1 M polymer in 2:1 (vol.) EC:DMC solution containing no additives (control), containing stabilizing... 968

Figure II.5.G.4. RAFT polymerization synthesis scheme for triflimide-based styrene polymer (PS-LiTFSI) 969

Figure II.5.G.5. Conductivity (mS/cm) & viscosity (mPa s) as a function of concentration for PS-LiTFSI in carbonate solutions 969

Figure II.5.G.6. Ideal transference number versus Li concentration (molal) for LiTFSI in EC:EMC (3:7). Each color represents a separate cell, with each cell polarized subsequently to ±5, ±10,... 969

Figure II.5.H.1. Theoretical design of the roadmap for an advanced Ti & LaMO dual modification 973

Figure II.5.H.2. 7Li MAS NMR spectra obtained before cycling and after cycling of NCM and NCM with modification. Morphology characterization of NCM and NCM with modification using TXM 974

Figure II.5.H.3. The ultrafine coating on both primary and secondary particle surface for the cathode 975

Figure II.5.H.4. The effects of PEDOT coating on electrochemical performance 976

Figure II.5.H.5. In situ synchrotron HE-XRD characterization on the structural evolution of LMO and LR-LMO during the first charge/discharge 977

Figure II.5.H.6. Qualitative structural analysis of LMO with different potentials and cycles 978

Figure II.5.I.1. Computational predictions of M-O decoordination and Ir=O/O-O mediated anion redox. (a) Local coordination environments predicted by DFT in a Li0.5Ir0.75Sn0.25O3 structure... 982

Figure II.5.I.2. Spatial distribution of the Ni and O oxidation state in the charged state after 125 cycles determined through STXM. The far left shows the distribution over an "electrode scale"... 983

Figure II.6.A.1. (a) GI/GB microstructure with average grain size 167 nm. (b) GI/GB microstructure with average grain size 60 nm. (c) Current focusing observed at the GB region plotted with... 987

Figure II.6.A.2. (a) GI/GB microstructure with larger grains (LG). (b) Strain energy (SE) and cracking at GB for LG. (c) GI/GB microstructure with small grains (SG). (d) SE and cracks at GB for SG 987

Figure II.6.A.3. (a) Computational domain of the cathode/SSE interface with presence of grain boundaries (GB). (b) Distribution of current density at the interface during the charge process... 988

Figure II.6.A.4. (a) Schematic diagram of the cathode/SSE interface where delamination can occur during the first charge or delithiation process. (b) Charge and discharge curves obtained... 988

Figure II.6.A.5. (a) Computational domain with large grain size of approximate diameter around 150nm. (b) Computational domain with smaller grain sizes of diameter approximately 75nm.... 989

Figure II.6.A.6. (a) The voltage vs. capacity performance curves as observed during the first, third and ninth CC-CV charge and CC discharge cycle as observed in the LLZO microstructures with... 989

Figure II.6.A.7. (a) Demonstration of change in potential with stoichiometry of Li in NMC cathodes during the charge process. Impedance analysis has been conducted at three different SOC... 990

Figure II.6.A.8. (a) Potential vs. Li stoichiometry curves as obtained during the charge and discharge processes. (b) Variation in charge transfer resistance with Li stoichiometry during charge... 990

Figure II.6.B.1. a-c) Cyclic voltammograms of LNMO, LNTMO and LTMO half cells in the first 10 cycles. The scan rate is 5 mV/min. d-f) Voltage profiles of LNMO, LNTMO and LTMO half cells... 993

Figure II.6.B.2. Comparison of operando DEMS measurements on a) LNMO and b) LTMO half-cells. The dQ/dV profiles (top panel) during the 1st charge are added to correlate with the gas... 994

Figure II.6.B.3. O K-edge mRIXS maps collected at pristine (P), charged (Ch) and discharged (D) states after various cycles: a) LNMO and b) LTMO. The voltage profiles of the selected cycles... 995

Figure II.6.B.4. a) mRIXS map and the corresponding RIXS cut emission spectrum collected at the excitation energy of 531 eV, b) and c) RIXS cut spectra of LNMO and LTMO collected at the... 995

Figure II.6.B.5. a, b) Schematics showing the probing depth of hard XAS (for Mn K-edge XANES) and soft XAS (for Mn L-edge), c, e) average Mn oxidation states derived from K-edge XANES... 997

Figure II.6.B.6. Schematics showing the effect of d0 TM on O redox behavior and subsequent degradation of the Mn redox-active cation-disordered rocksalt cathodes 998

Figure II.6.C.1. Schematic illustrations of different Li transport models in amorphous coating 1001

Figure II.6.C.2. (a) Trajectory of one Li+ atom in Li0.3Al₂O₃.15 (electrolyte model) for 40 ps at 2000K. Yellow and green dot srepresent vibrational and translational motions, respectively.... 1002

Figure II.6.C.3. Coordination number of Li+ with PC computed in the present work and compared to experimental values (left) and fraction of Li+ with n PF6- anions (middle). Representative... 1002

Figure II.6.C.4. Bulk electrolyte conductivity of LiPF6 electrolyte as a function of salt concentration. Experimental data taken from Takeuchi et al. 1003

Figure II.6.C.5. Diffusion constants of Li+ and BF4- in propylene carbonate as a function of concentration 1003

Figure II.6.D.1. Calculated Li2S-P4S7-S phase diagram using SCAN functional 1006

Figure II.6.D.2. (a) Comparison of binary sulfide formation energy calculated from PBE and SCAN with experimental measurement. (b) ΔG vs. T for Li7P3S11 & Li4P2S7 1006

Figure II.6.D.3. (a) Comparison between calculated and experimental PDFs for amorphous LPS. (b) Raman spectra calculated for different LPS crystalline phases 1007

Figure II.6.D.4. (a) Electrochemical stability windows of 1,600 phase-stable materials categorized by anion chemistry. (b) Chemical reaction energy ΔE rxt with LPS and fully lithiated NCM... 1008

Figure II.6.D.5. Computational structures of the amorphous Li-P-S systems including different types of anion building blocks at same composition. Green, purple and yellow balls denote Li, P... 1009

Figure II.6.D.6. Arrhenius plots of AIMD simulation on the Li-P-S systems with different concentrations of anion building blocks, PS43-, P2S64- and P2S74- 1009

Figure II.6.E.1. A Newman-type model was adapted to rapidly predict the effects of heterogeneity by placing dissimilar regions in parallel. The model is able to show why lithium plating occurs... 1013

Figure II.6.E.2. Temperature, current, and positive and negative electrodes states of charge (SOCs) distributions, along with charge curves for the charging aligned resistances case (hot-hot,... 1014

Figure II.6.E.3. (a) Conceptual geometry (not to scale) of revised local conductivity probe and (b) XYZ stage for automated measurement of local conductivity 1015

Figure II.6.E.4. An example localized conductivity measurement with ionic conductivity given in terms of dimensionless MacMullin Number, for a commercial LCO electrode 1016

Figure II.6.E.5. Schematic of XYZ stage and head unit for local electronic conductivity probe. This unit was adapted for use in measuring ionic conductivity as well, as shown in the adjacent figure (b) 1016

Figure II.6.E.6. Snapshots of beginning and ending particle configurations for drying and calendering SPH simulations. The colored spheres indicate active material (blue), carbon/binder (yellow),... 1017

Figure II.6.F.1. The Li diffusion pathways for different solid electrolytes (the yellow isosurfaces), compared with the ab initio calculated transition pathways (the arrows) 1021

Figure II.6.F.2. (a) Side view of schematic representation of liquid electrolytes. (b) One representative local structures of the coordination environments around a Li-ion. (c) Li-O and (d) Li-F... 1021

Figure II.6.F.3. Mean square displacement (MSD) plots of Li-ion and PF6-ion taken from 30 ps NVT at 600 K simulations in bulk LE and LiF/LE interface 1022

Figure II.6.F.4. The stacking structure of LixSy/2D-HAB-CP at different level of lithiations. 1022

Figure II.6.F.5. Li-migration barriers distribution (a) and diffusion coefficients as a function of temperature (b) of Mn-HAB-Li5S8, Mn-HAB-Li10S8, and Mn-HAB-Li15S8, in the X and Z-directions.... 1022

Figure II.6.F.6. (a) vulcanization of 5-Decene in two methods (cycloaddition and crosslinking); (b) two different positions of C=C in Decene are considered as vulcanization sites. The numbers... 1023

Figure II.6.F.7. The lithiation process of S vulcanized 5-Decene 1024

Figure II.6.G.1. The calculated total density of states (TDOS) for the four SE surface structures aligned with the vacuum level. The position of CBM of the corresponding bulk structure is labeled... 1026

Figure II.6.G.2. The distribution of additional electrons (yellow region), which is calculated from the difference in charge density before and after inserting additional electrons 1027

Figure II.6.G.3. Phase-field simulation results on the impacts of surface trapped electrons and grain size on the morphologies and electric potential distributions after 800s Li electrodeposition.... 1028

Figure II.7.A.1. Discharge of the Li-solid electrolyte interface is sensitive to pressure. Comparison (left) of the pressure- induced creep-strain rate and the current-induced strain rate for stripping... 1035

Figure II.7.A.2. Typical load displacement curves (a) show the punch-in displacement that occurs at a range of displacement. An undulation in the surface (b) is proposed to model an interface... 1036

Figure II.7.B.1. a, In-plane scanning electron microscopy (SEM) image of sintered LICGCTM thin film. b, cross-section view of the LICGCTM/xPEO composite thin film. c and d, equibiaxial flexural... 1040

Figure II.7.B.2. a. Composition of the gel composite electrolyte. b. storage moduli of gel composite electrolytes as a function of temperature, measured by dynamic mechanical analysis.... 1041

Figure II.7.B.3. Composites consisting of LICGCTM ceramic and 3 different polymers: PEGDMA crosslinked with LiTFSI free salt, with covalently bound styrene sulfonate anion and with... 1042

Figure II.7.B.4. Cycling of Li/LiFePO₄ solid state cells with dry composite and polymer electrolytes. a, cells at cycle 10 with different thicknesses of excess Li, 0-120 μm; b, reduced polarization... 1042

Figure II.7.C.1. Temperature dependence of ionic conductivity of (a) carbonate SCEs, (e) ether SCEs, (i) alkylphosphate SCEs. Electrochemical stability of (b) carbonate SCEs, (f) ether SCEs,... 1045

Figure II.7.C.2. (a) Linear sweep voltammetry curves of PQILEs of Li(DME)xFSI-PEO0.6 on Pt electrode in a three-electrode cell with a scan rate of 0.5 mV s-1. (b) Temperature dependence... 1046

Figure II.7.C.3. (a) XPS profiles of the pristine NMC333 cathode and NMC333 cathodes after 300 cycles with different charge cut-off voltages of 4.2, 4.3, 4.4 and 4.5 V. TEM images of NMC... 1047

Figure II.7.C.4. (a) Nucleation overpotentials of Li plating on Li, Li-Ag, and Li-Ag-LiF surfaces in a carbonate electrolyte of 1 M LiPF6 in EC-DMC (1:2 by vol.) (b) Cycling performance of Li||NMC333... 1048

Figure II.7.D.1. (a) Energy profile of Li deposition on Cu(001) from DME-solvated LiFSI in absence of an external field. ∆E values are energies relative to the initial configuration shown at the left.... 1051

Figure II.7.D.2. Effects of reaction rate and surface diffusion barrier on the development of metal nucleation morphology as calculated from KMC simulations. From Energy Storage Materials,... 1052

Figure II.7.D.3. LiTFSI decomposition on LiOH/Li. (a) Snapshots illustrating decomposition dynamics. (b) Net Bader charges of system components for DME and 1 M LiTFSI with Li/LiOH. (c) Bader... 1053

Figure II.7.D.4. Simulation cell contains Li metal surface (read atoms) interfacing with a solid-state electrolyte Li9N2Cl3 (Li: purple, N: brown, Cl: green). (a) Input potential (red line) and potential... 1054

Figure II.7.E.1. (a) Equilibrium plating potential of Li arising due to compositional variation at the Li-metal/electrolyte interface illustrating the condition for dendrite formation. (b) Variation of Li... 1059

Figure II.7.E.2. (a) Variation of Li metal plating and stripping potential for 25th cycles of SIA cycled at a current density of 1mA cm-² with plating areal capacity 0.5mAh cm-² (b) Variation areal... 1059

Figure II.7.E.3. (a) Variation areal capacity with cycle number of MCA showing excellent cycle life with CE ~99.9% cycled at 1mA/cm² . (b) Variation of Li metal plating and stripping potential... 1060

Figure II.7.E.4. (a) Variation areal capacity with cycle number of IES showing excellent cycle life with CE ~99.4%. (b) Variation of Li metal plating and stripping potential for 96th-100th cycles... 1060

Figure II.7.E.5. SEM micrograph of Li metal growth front obtained after 100 cycles 1061

Figure II.7.E.6. a) Electrochemical cycling, b) Voltage profile after 40 cycles, c) SEM after 200 cycles showing absence of dendrites, scale bar 10 microns 1061

Figure II.7.E.7. Nucleation and growth behavior of carbon nano -architectures at different current rates 1062

Figure II.7.E.8. Variation of potentials of Li plating on carbon nanoarchitectures at different current densities 1062

Figure II.7.E.9. Columbic Efficiency of Li plating and deplating @1mA/cm², 4mAh/cm² in Li/Li+ cell 1063

Figure II.7.E.10. Voltage vs. time (hours) profile of carbon-based electrodes at the transition region in traditional coin cell testing 1063

Figure II.7.E.11. Schematic of the traditional and insulated coin cell testing along with the recorded performance for copper foils 1064

Figure II.7.E.12. Columbic Efficiency of Li plating and de-plating @4mAh/cm², 4mAh/cm² in Li/Li+ cell (Insulated coin cell) 1065

Figure II.7.F.1. (a) Electrokinetic phenomena (e.g. electrokinetic surface conduction and electroosmosis) in 3D PPS under electric field. (b) Electro-diffusion of Li ions in traditional cells under... 1068

Figure II.7.F.2. The Li-ion electrokinetic self-concentrating and pumping features of the 3D PPS. (a) Linear sweep voltammetries of 3D PPS@Cu and bare Cu electrode, (b, c) Equilibrium Li-ion... 1068

Figure II.7.F.3. The morphology of Li metal deposited on the different electrodes. SEM images of Li metal deposited on the bare Cu electrode (a-b) and 3D PPS@Cu (c-f) at a deposition capacity... 1069

Figure II.7.F.4. The morphology of Li metal deposited on the 3D PPS@Cu at different deposition capacities and current densities. LiTFSI/DOL+DME+1 wt% LiNO3 1069

Figure II.7.F.5. The morphology of Li metal deposited on the 3D PPS@Cu at extremely high current densities and a deposition capacity of 4 mA h cm-². (a-d) At a current density of 12 mA cm-².... 1069

Figure II.7.F.6. The morphology of Li metal deposited on the bare Cu electrode and 3D PPS@Cu at -10℃ with a high current density of 20 mA cm-² and a deposition capacity of 4 mA h cm-² 1069

Figure II.7.F.7. The morphology of Li metal deposited on the bare Cu electrode and 3D PPS@Cu at -10℃ with a high current density of 20 mA cm-² and a deposition capacity of 4 mA h cm-² 1069

Figure II.7.F.8. (a), CE of Li deposition on 3D PPS@Cu and bare Cu electrode at a current density of 2 mA cm-² and a deposition capacity of 2 mA h cm-². (b), CE of Li deposition on 3D... 1070

Figure II.7.F.9. Optical images of (a) just mixed solution of starting materials, (b) after 10 h. Optical images of (c) just mixed solution of starting materials on SS foil and (d) after drying overnight... 1070

Figure II.7.F.10. High-resolution XPS spectra of Cl 2p, C 1s and S2p for (a and b) pure chlorine-rich polymer, (c) Sn-containing trifunctional crosslinker lithium polysulfidophosphate and (d-f)... 1071

Figure II.7.F.11. (a,b) Top-view and (c) side-view SEM images of the as-prepared MSCP film on SS foil 1072

Figure II.7.F.12. (a,b) Top-view and (c) side-view SEM images of deposited Li on bare SS foil after 10 cycles. (d,e) Top-view and (f) side-view SEM images of deposited Li on MSCP protected... 1072

Figure II.7.F.13. S 2p, P 2p, Cl 2p, and Li 1s XPS spectra of (a)−(d) MSCP-SEI and (e)−(h) control SEI. (i) Elemental composition comparison of control SEI and MSCP-SEI calculated on the basis... 1072

Figure II.7.F.14. C 1s, F 1s, and N 1s XPS spectra of (a-c) MSCP-SEI and (d-f) control SEI 1073

Figure II.7.F.15. CEs of cells using bare (black) and MSCP protected (red) SS foil versus cycle number at (a) 1 mA cm-² and 1 mAh cm-², (b) 2 mA cm-² and 2 mAh cm-², (c) 2 mA cm-²... 1073

Figure II.7.F.16. (a) Cycling performance of symmetric cells using bare (black) or MSCP protected (red) Li metal foils cycled at 2 mA cm-² and 2 mAh cm-² . (b) Cycling performance of Li... 1074

Figure II.7.F.17. (a) Electrokinetic phenomena (i.e. electrokinetic surface conduction) enhance Li-ion transport in the leaky film under applied electric field in the electrolyte. (b-d) SEM morphology... 1075

Figure II.7.F.18. The morphologies of Li metal deposited on the PPS@Cu at (a-c) a deposition capacity of 2 mAh cm-² and a current density of 1 mA cm-² , (d-f) a deposition capacity of 4 mAh... 1075

Figure II.7.F.19. The morphology of Li metal deposited on the PPS@Cu at different deposition capacities and current densities. (a-c) 6 mA h cm-² and 6 mA cm-² . (d-f) 4 mA h cm-² and... 1075

Figure II.7.F.20. Electrochemical performance of PPS@Cu and bare Cu foil electrodes. CE of Li plating/stripping on PPS@Cu and bare Cu foil at a current density of 1 mA cm-² and a deposition... 1076

Figure II.7.F.21. Cycling performance of full cells using PPS leaky film protected Li metal as anodes and NCM-811 as cathodes. (a) Flooded electrolyte. (b) Lean electrolyte of 5 µl/mA h. (c) Lean... 1076

Figure II.7.F.22. (a) The photos of prepared FSS electrodes. (b) FT-IR spectra of FSS electrode 1077

Figure II.7.F.23. Li₂S6 adsorption of FSS electrodes 1077

Figure II.7.F.24. (a) The cycling performance of the FSS electrode with various S mass loading of 6, 8.78 and 10 mg cm-² at an E/S ratio of 10 µl mg-¹ . The cycling performance of the FSS... 1078

Figure II.7.F.25. (a) Cycling performance of the FSS electrodes with the S mass loading of ~11.67 mg cm-² at the E/S ratios of 5 µl mg-¹ . (b) Cycling performance of the FSS electrodes with... 1078

Figure II.7.G.1. Examples of generated digital microstructures of polycrystalline LLZO with (a) different grain sizes; and (b) different grain boundary thicknesses 1082

Figure II.7.G.2. Workflow for computing the effective ionic diffusivity/conductivity of reconstructed digital representation of a solid electrolyte microstructure 1082

Figure II.7.G.3. Characterized kink temperatures of computed temperature-dependent ionic conductivities of polycrystals with (a) increasing grain size; and (b) increasing grain boundary thickness 1083

Figure II.7.H.1. Morphology of LLZTO powders under various high-energy ball milling conditions. (a) Raw powders purchased from MTI Corporation. (b) Dry milled powders. (c-i) powders milled... 1087

Figure II.7.H.2. (a) XRD of powders before ball milling (black), and after ball milling in acetonitrile/Triton X-100 (red) and ethanol (blue). x values in (Lix) represent Li contents in LixLa3Zr1.4Ta0.6Oy... 1087

Figure II.7.H.3. (a-d) and (e-h) are SEM images of pristine and MT-milled LLZTO powder pellets sintered at 950℃, 1000℃, 1050℃, and 1100℃, respectively. (i) Relative density of LLZTO pellets... 1088

Figure II.7.H.4. PEGDA recipe: 3D printing and post sintering. PEGDA/LLZTO ink was first printed as a thin film using the paste PuSL system, and then zig-zag structures with varying spacings... 1089

Figure II.7.H.5. Sintering of DIW-extruded LLZTO filaments. (a) 1100℃ furnace-sintered filament from raw powder LLZTO/NMP (83 wt%) ink. (b) 1100℃ furnace-sintered filament from ball... 1090

Figure II.7.I.1. (a) Chemical structures of the liquid compounds studied in this work. (b) Lithium/Lithium cycling at 0.5 mA/cm2 to 0.5 mAh/cm2 as a function of electrolyte content. (c) Li/Li... 1094

Figure II.7.I.2. (a) SEM image of the lithium deposition morphology at a current rate of 1 mA/cm2 to 0.1 mAh/cm2 as afunction of electrolyte content. (b) 7Li NMR chemical shifts of 0.1 M... 1095

Figure II.7.I.3. a, Chemical structure of PDMS Self-Healing Polymer (SHP). b, FTIR Spectra of the PDMS-IDPI with varying size of PDMS soft block in the co-polymer. c, Oscillatory shear... 1096

Figure II.7.I.4. a, Chemical structure of PDMS-IDPI Self-Healing Polymer. b, FTIR Spectra of the PDMS SHP with varying size of PDMS soft block in the co-polymer 1097

Figure II.7.I.5. a, Typical voltage profile of Li||PDMS-SHP@Cu cells. b, Coulombic efficiency comparisons of the PDMS SHP with varying size of PDMS soft block as well as H-bonding strengths... 1097

Figure II.7.I.6. a, Oscillatory shear measurements at stain 1% for the different self-healing polymers. b, Coulombic efficiency comparisons of the polymer SHP with varying H-bonding strengths... 1098

Figure II.8.A.1. (a) Voltage profiles of Li plating/striping cycling with a current density of 0.5 mAcm-² at room temperature (inserted: voltage profiles of PEO and PEO/LLTO tested at 201-203... 1101

Figure II.8.B.1. (a) POSS-PEO-POSS (5-35-5) chemical structure (b) Example of a routine used to test the limiting current of POSS-PEO-POSS (5-35-5) 1105

Figure II.8.B.2. Voltage as a function of time during preconditioning cycles for a lithium symmetric cell and a POSS-PEO- POSS/LiTFSI r = 0.04 electrolyte. This cell was cycled at a current... 1106

Figure II.8.B.3. Nyquist plot of a lithium symmetric cell before and after the conditioning cycles shown in Fig. 1. Bulk resistance was unchanged and interfacial resistance increased by... 1106

Figure II.8.B.4. Interfacial resistance of PEO-POSS 5k-1k with ethyl, isobutyl, and isooctyl end groups as a function of salt concentration 1107

Figure II.8.B.5. 7Li NMR spectra (open circles) of (a) 5 kg mol-1 (b) 35 kg mol-1 and (c) 275 kg mol-1 PEO annealed against lithium metal for 12 days at 130℃ in a coaxial NMR tube with... 1108

Figure II.8.B.6. Conductivity of 35 kg mol-1 PEO, containing no lithium salts, annealed at 120℃ in a lithium symmetric cell (closed symbols) and a stainless-steel symmetric cell (open symbols)... 1109

Figure II.8.B.7. (a) Impurities are present in lithium as-received. Cross-sectional slice through cell with additional cross section of pure lithium showing impurity particles. (b) Volume reconstruction... 1110

Figure II.8.B.8. Correlation between current density and defect density in failed cells. The areal density of protruding defects, P, increases with current density 1110

Figure II.8.B.9. Slice through a reconstructed volume imaged using X-ray tomography. This Li/POSS-PEO-POSS/Li cell was cycled at 0.175 mA cm-² and failed after 17 cycles 1111

Figure II.8.B.10. Strategy of the electrochemical filtering treatment to push impurity particles away from the interface. (a) Schematic of the electrochemical filtering treatment. After symmetric... 1111

Figure II.8.B.11. Galvanostatic cell cycling example and results. (a) Current density and voltage of the first cycles at 0.12 mA cm-² for one cell. During each cycle, current was applied for 4 h at... 1112

Figure II.8.B.12. Representative cross section of cell polarized at i = 0.04 mA cm-² for t = 900 h acquired using X-ray tomography. Lithium was deposited downward through the polymer... 1112

Figure II.8.B.13. Comparison of the calculated and experimental limiting currents of a POSS-PEO-POSS hybrid inorganic- organic block copolymer electrolyte and a PS-PEO all-organic block... 1113

Figure II.8.C.1. (a) Schematic of the experimental design in the initial state, after plating Li on the Ni current collector and after interface formation and stripping of the Li. (b) Photographs of... 1118

Figure II.8.C.2. Plating and stripping profile of a Cu foil/PEO-LiTFSI/Li metal cell 1119

Figure II.8.D.1. Structural characterization of ß-Li₃PS₄ prepared through a solution-based route showing (a) X-ray diffraction (XRD) patterns and (b) Raman spectra of the precursors and... 1122

Figure II.8.D.2. Ionic conductivity measurements of ß-Li₃PS₄ solid electrolyte pellets. (a) Conductivity cell configuration, (b) representative Nyquist plots of a C/ß-Li₃PS₄/C cell at 23-78℃,... 1123

Figure II.8.D.3. AC impedance measurements on a Li/ß-Li₃PS₄/C cell used to determine the oxidative stability limit of the ß-Li₃PS₄ solid electrolyte. (a) Nyquist plots collected by polarizing... 1123

Figure II.8.D.4. Structural characterization of a-Li₃PS₄ + PEO composite solid electrolytes. (a) XRD patterns of composites containing 0.2 - 56 wt% PEO. (b) XRD patterns of a-Li₃PS₄ + 1 wt%... 1124

Figure II.8.D.5. Raman spectra of a-Li₃PS₄ + 1 wt% PEO after heating for 12 h at 25 - 250℃ showing (a) 100-1,000 cm-¹ and (b) 1,000 - 3,500 cm-¹ regions 1125

Figure II.8.D.6. Li+ conductivity for several a-Li₃PS₄ + PEO composite solid electrolytes. The sample denoted a-Li₃PS₄ + 5% PEO/LiTFS contained PEO/lithium trifluoromethanesulfonate... 1125

Figure II.8.D.7. (a) Li-P-S ternary phase diagram. Due to limited available thermodynamic quantities (e.g., free energies of formation), not all tie lines are known for this system. (b) X-ray... 1126

Figure II.8.E.1. Bulk Stability of doped-LLZO in Contact with Metallic Li: (a) Nb 3d and (b) Zr 3d core level XPS spectra and (c) Al L-edge XAS spectra reveals (a) the reduction of Nb, (b) no... 1130

Figure II.8.E.2. Galvanostatic cycling of Al- doped LLZO: a) Symmetric Li/Al-LLZO /Li coin cell cycled with the current density of 4 mA cm-² b) Charge and discharge voltage profiles after 3h... 1132

Figure II.8.E.3. Effect of LLTO Crystallinity on Reactivity with Metallic Li (a) XPS and (b) XAS spectra of amorphous LLTO film after contacting with Li metal. (c) XAS of crystalline LLTO films... 1133

Figure II.8.E.4. Li-LLTO Ab Initio Molecular Dynamics: AIMD trajectories for (a) Li/LLTO (001) interface; (b) Li/LLTO (100) interface and (c) Li/amorphous LLTO interface. Initial atomic positions... 1134

Figure II.8.F.1. Illustration of transport challenges, both ionic and electronic identified and addressed in this work 1137

Figure II.8.F.2. Illustration of the transport challenges, both ionic and electronic identified and addressed in this work 1138

Figure II.8.F.3. Voltage profile of a 12 V cell architecture with a modified electrode aspect ratio. The cell cycled between 7.5 V and 13.5 V following a charge protocol with incremental capacity... 1138

Figure II.8.F.4. Impact of electrolyte additive on the utilization of the positive electrode for 12 V self-formed cells cycled between 7.5 and 13.5 V. The cells were charged at constant voltage... 1139

Figure II.8.F.5. Comparison of the positive electrode utilization and electrode pairs' energy density for the 12 V cell configuration with variations on the cell design. The variations that were... 1140

Figure II.8.F.6. Comparison of the positive electrode utilization and electrode pairs' energy densities for the single cell configuration with variations in cell design. Variations include orientation,... 1140

Figure II.8.F.7. Positive electrode utilization for single cell configurations with different lithium ion dopant quantities, in the first cycle. The cells were cycled between 1.5 V and 3.5 V 1141

Figure II.8.F.8. Positive electrode utilization of optimized single cell designs, without and with nanolayered multicomponent electrodes in the first two cycles. Cells were cycled between... 1142

Figure II.8.F.9. Positive electrode utilization for the first cycle of single cell configurations with 90 micron spacing and different hybrid electrolyte compositions. The cells were cycled between... 1142

Figure II.8.F.10. Cycling efficiency comparison for the first four cycles of single cell configurations with lithium enrichment, nanolayered electrode composition, and the optimized cell design.... 1143

Figure II.8.G.1. 1H DOSY-NMR spectra of (a) 1:1 VC:EMC, (b) 1:4:4 LiPF6:VC:EMC, (c) 1:1 VEC:EMC and (d) 1:4:4 LiPF6:VEC:EMC with toluene added as an internal reference 1147

Figure II.8.G.2. Voltage profiles for Li/Li symmetric cells cycled at 2 mA cm-² with Gen2 with 2% VC and Gen2 with 2% VEC electrolytes 1148

Figure II.8.H.1. Structure of LLZO (001) and NMC (10 -14) interface that is calculated using density functional theory 1151

Figure II.8.I.1. Cell Design A: (A) pre-charge AC Impedance, (B) Comparison of first cycle charge curve 1155

Figure II.8.I.3. Cell Design A: (A) EIS (B) Resistance v. cycle, (C) Cycling, (D) Coulombic efficiency v. cycle number 1155

Figure II.8.I.2. Coulombic efficiency under extended cycling in cell constructions B I-B IV with comparison to A I 1155

Figure II.8.I.4. Coulombic efficiency in cell constructions B I, B III, B IV and A I at (A) higher and (B) lower DoD at 40℃ and Impedance measurements at elevated temperature prior to charging,... 1156

Figure II.8.I.5. X-ray diffraction of composite solid electrolyte A) Prior to cell assembly, B) Removed from cell after charge 1156

Figure II.8.I.6. SEM/EDS analysis of cells post charge, L) Cathode side, R) Anode side 1156

Figure II.8.I.7. EDXRD stack plot for uncharged LiI solid electrolyte with LiI(HPN) 2 additive 1157

Figure II.8.I.8. EIS of Control, Process I, II, III A) Before charge, B) After charge to 0.5%, and C) Discharge profile 1157

Figure II.8.I.9. Demonstration of self-healing A) Under high current density, B) Same cell cycled under lower current density 1158

Figure II.9.A.1. Raman spectra of siloxane, DOL and siloxane-based electrolytes with increased concentration in the Raman shift range of (a) 580-650 cm-1 and (b) 730-760 cm-1. Typical... 1160

Figure II.9.A.2. BET measurement results of two highly porous carbon (HPC) hosts in this study: (a) HPC1 and (b) HPC2 1161

Figure II.9.A.3. Cycle performance of S-HPC1 (70 wt.% S) composite in (a) dilute ether, (b) concentrated ether and (c) concentrated siloxane electrolytes. (d) Coulombic efficiency comparison... 1161

Figure II.9.A.4. (a) Representative current relaxation curve collected to extract the static leakage current. (b) Leakage current measurement of S-HPC1 composite in different electrolytes.... 1161

Figure II.9.A.5. Li metal plating/stripping in Li/Li symmetric cells in (a) dilute ether and (b) concentrated electrolytes at 1.25 mA cm-² with an areal capacity of 1.25 mAh cm-² . SEM image... 1162

Figure II.9.A.6. (a) S 2p spectra of Li metal in the Li/S-HPC1 cells after 20 cycles in different electrolytes at C/10. F 1s spectra of Li metal in Li/S-HPC1 cells after 20 cycles in different... 1163

Figure II.9.A.7. Flammability test: (a) dilute ether; (b) concentrated ether and (c) concentrated siloxane 1164

Figure II.9.B.1. Schematic of the hybrid electrode design, in which solid electrolyte and liquid electrolyte are filled in the big voids and small pores of electrode, respectively, to enable the robust... 1167

Figure II.9.B.2. (a) XRD patterns of the glass phase (bottom), LT-LPSBI (middle) and HT-LPSBI (top). (b) Nyquist plot of an In- SE-In (SE = LT-LPSBI) cell tested at various temperatures.... 1168

Figure II.9.B.3. (a) Cyclic voltammogram for a C-SSE/SSE/Li cell at a scan rate of 5 mV/s (SSE=LT-LPSBI). (b) Nyquist plots of a Li/SSE/Li cell at room temperature as a function of time... 1168

Figure II.9.B.4. (a) Nyquist plot of a S-SE/SE/Li cell at room temperature for the frequency range of 100 kHz to 0.01 Hz (voltage modulation was 5 mV, SE=LT-LPSBI). (b) First two cycle... 1169

Figure II.9.B.5. Interfacial stability of liquid electrolytes with Li anode and SSE contained sulfur cathode. Nyquist plots of Li/Li symmetric cells with (a) 1M LiTFSI/DOL/DME+0.3M LiNO 3 (E-121),... 1170

Figure II.9.C.1. (a) Schematic of the electrochemical cell design that allows in-operando dark field light microscopy (DFLM) observation. (b and c) DFLM images of the metal grid (50 nm thick,... 1175

Figure II.9.C.2. (a) In-operando DFLM images of sulfur droplets electrochemically formed on Pd, Pt, indium tin oxide (ITO) and cobalt sulfide (CoS2) substrates. (b) Time-lapse in-operando... 1176

Figure II.9.C.3. (a) DFLM image of exfoliated graphite nano-platelets dispersed on Ni metal grid for growing solid and liquid sulfur in the same cell. (b) High-magnification bright field light... 1177

Figure II.9.C.4. (a and b) Time-lapse light microscopy images of the initial formation of sulfur droplets, one on the Ni grid (a) and another off the Ni grid on glass (b). (c) Two general... 1178

Figure II.9.C.5. (a) Charge/discharge voltage profiles of the Ni, C, and Al electrodes at a current density of 0.05 mA cm-² . (b) Cycling stability of the Ni, C, and Al electrodes at a current... 1179

Figure II.9.C.6. Optical images of the Al electrode in lithium polysulfide electrolyte (a) at initial state, (b) after charging to 3.0 V, and (c) after discharging to 1.0 V. Optical images of the C... 1180

Figure II.9.C.7. SEM images of the discharging products formed on the (a) Al, (b) C, and (c) Ni substrates. Inset in (c) is the magnified area indicated by the red circle. SEM images... 1181

Figure II.9.C.8. Schematic illustration of the sulfur species evolution on (a) Ni, (b) C, and (c) Al substrates during charging and discharging processes 1182

Figure II.9.D.1. Prevent dissolution of the polysulfide ions and their reaction with the anode 1184

Figure II.9.D.2. Example of synthesis route of a sulfur co-polymer compound. Chalker et al, Green Chem. 2017,19,2748 1185

Figure II.9.D.3. The selection of possible cross-linking groups for the co-polymers 1185

Figure II.9.D.4. Comparison of relative capacity retention of three selected copolymer cathodes 1186

Figure II.9.D.5. Copolymerize sulfur with p-Phenylene vinylene to form crosslinked sulfur-rich S/Xant- copolymer 1187

Figure II.9.D.6. Rate performance of a coin cell made of fully prelithiated Phosphorus anode and 75% Sulfur/carbon cathode (up); the cyclability of the cell (low). copolymer 1187

Figure II.9.D.7. Schematic illustration of the S/P batteries (low/left); rate and cycling performance of a fully prelithiated P/C anode prepared through patented chemical methods (up);... 1189

Figure II.9.D.8. (A) The sulfur cathode is a polymeric sulfur (co-polymerization with monomer) electrode, the averaged capacity is 0.805 mAh discharge/charge; (B) The sulfur cathode is an... 1189

Figure II.9.D.9. Cycle life of sulfur and polymer sulfur cathodes with metal sulfide additives 1189

Figure II.9.E.1. Schematic representation of the FC surface with attached polysulfide molecule (removal of Li or S atom represents reaction 1 or 2, respectively) and free energies of reaction... 1193

Figure II.9.E.2. Electrochemical cycling of PTA-DDSA electrode using the Batt 500 lean electrolyte protocol 1194

Figure II.9.E.3. Li ion conductivity of the doped LICs predicted by theoretical analysis using DFT 1194

Figure II.9.E.4. a) EIS analysis of the Li-S batteries fabricated using the doped LIC coated sulfur electrodes as cathodes; Figure b) Cycle life performance of the doped and undoped LIC coated... 1195

Figure II.9.E.5. Synthesis of Cu-bpy-CFM and sulfur infiltrated S-Cu-bpy-CFM electrodes (EnergyTechnol.2019, 1900141, https://doi.org/10.1002/ente.201900141) 1195

Figure II.9.E.6. (a): Cycling performance of doped and undoped LIC coated S-Cu-bpy-CFM cathodes cycled at a rate of 100 mA/g. Figure II.9.E.2(b): Rate capability performance of the doped... 1196

Figure II.9.E.7. a: Cycling performance of EC-CFM-S and 7b: Cycling performance of LIC-CFM-S 1196

Figure II.9.E.8. Free energies of reaction 1 and 2 for different metal oxides as functional catalytic materials and polysulfides 1197

Figure II.9.F.1. Left section. Long chain polysulfides confinement mechanism is illustrated at the upper part: the C-S bonds generated after vulcanization provide a reservoir for long chain... 1200

Figure II.9.F.2. SEM images of (a, b, c) commercially available micron sulfur and (d, e, f) vulcanized PIPS and sulfur nanocomposite materials particles. The particle sizes of the samples vary... 1201

Figure II.9.F.3. Electrochemical characterization of PIPS and sulfur nanocomposite materials based sulfur electrode and comparison to micron sulfur based electrode. The composition of cathode... 1202

Figure II.9.G.1. a) Specific capacity (mAh/G sulfur) for Li-S cells of indicated cell structure [anode | electrolyte-separator | binder/gel-cathode] during Galvanostatic cycling at 0.1C (calculated... 1207

Figure II.9.G.2. GITT results for six different Li-S coin cell designs, with the cell structure indicated as Li | (electrolyte) | (cathode). All data was collected at 30℃ and C/10 rate (assuming... 1208

Figure II.9.G.3. a) Cycling performance of QSS and OE cells, with a 100h rest during 7 th cycle discharge. Some irreversible capacity loss is observed for both designs, but the OE cell exhibits... 1210

Figure II.9.G.4. a) Visual test of the reaction/interaction between Li2S8 (1 mM) in DOL/DME (1;1, v:v) with 1 M LiTFSI. b) UV-vis spectra of solutions with various ratio between dbNDI and... 1212

Figure II.9.G.5. a) Cycling performances of S cathodes with PP and PVDF as binder, respectively: b) S cathodes fabricated using PP as binder with different ratio between PENDI-350 and tri-Py;... 1213

Figure II.9.G.6. a) Cycling performances of S cathodes with PENDI-350 (2.0 mgS/cm²) and PVDF (3.1 mgS/cm²) as binder, respectively; b) SEM images of cathodes with PENDI-350 and... 1215

Figure II.9.G.7. Cycling performances of cells with S cathodes with a) PENDI-350/PEO as binder (3.71 mgS/cm²) and b) PENDI-350/triPy/PEO (PPP) as binder (2.91 mgS/cm²). All cells were... 1216

Figure II.10.A.1. (a) Schematic images of Li-O₂ cells composed of Li metal anodes and CNT air cathodes with different electrolytes: PEO with 1 M LiTf-TEGDME (left), PEO with 3 M LiTf-TEGDME... 1221

Figure II.10.A.2. (a) Schematic of traditional artificial membrane on as-received Li foil surface and current CPL applied by direct casting on Li foil. (b) Cyclic stability tests based on Li||Li cells.. 1222

Figure II.10.A.3. (a) Schematic images of different anodes and improvement by 3D carbon host for Li/C composite anodes and protective layer (NCL) coating for surface stabilization. (b) Cyclic... 1223

Figure II.10.A.4. (a, b) TEM image and corresponding FFT pattern of (a) pristine RuO₂/CNT electrode and (b) pretreated electrode. (c, d) Cyclic stability tests of Li-O₂ cells composed of RuO₂/... 1224

Figure II.10.B.1. SEM of (a) 1st discharge and (b) charge products in Li−O₂ batteries with the Co2Ni@LiOH cathode. (c) XRD of the 1st, 20th, 30th, and 40th discharge and the 1st charge... 1228

Figure II.10.B.2. (a) Discharge profile of Ir-rGO under O₂ followed by discharge profile under Ar flow (b) PEIS measurements performed on pristine cathode, after O₂ discharge, after... 1230

Figure II.10.C.1. Voltage profiles for Li-O₂ battery with LiNO3 salt (left), and LiI redox mediator (right) 1233

Figure II.10.C.2. (left) Voltage profiles for Li-O₂ battery with 1M LiNO3 and 1M LiI in 75% TEGDME/ 25% IL; (right) Raman spectra showing the presence of Li2O₂ in the discharge product 1234

Figure II.10.C.3. AIMD simulation of eight LiNO₃ molecules added to electrolyte showing them forming a layer on the lithium anode 1234

Figure II.10.C.4. Redox potentials (vs Li+/Li) of redox mediators measured from CV experiments in DMSO 1235

Figure II.11.A.1. Structure evolution during Na extraction and insertion. In situ XRD patterns of Na0.7[Cu0.15Fe0.3Mn0.55]O₂ electrode collected during a) the first and b) the fifth charge/... 1240

Figure II.11.A.2. XAS analysis of a-c) Na0.7[Cu0.15Fe0.3Mn0.55]O₂ and d-f) Na0.7[Cu0.2Fe0.2Mn0.6]O₂ electrodes at different SOCs during the 1st and 11th cycle: XANES spectra at a),... 1241

Figure II.11.A.3. sXAS of Na0.7[Cu0.15Fe0.30Mn0.55]O₂ (a-c) and Na0.7[Cu0.20Fe0.20Mn0.60]O₂ (d-f) samples. The Cu L-edge, (a and d), Fe L-edge (b and e), and O K-edge (c and f) sXAS... 1242

Figure II.11.A.4. Crystal Structural Evolution of Na0.72[Li0.24Mn0.76]O₂ Electrodes. (A) In situ XRD patterns collected during the first charge/discharge and the second charge of the Na0.72... 1243

Figure II.11.B.1. (a) X-ray Diffraction and (b) Raman spectra of Black Phosphorus-Carbon Composite. SEM images of (c) Bulk phosphorus and (d) black phosphorus-carbon composite, (e) High... 1247

Figure II.11.B.2. (a) Initial voltage profile of black phosphorus-carbon composite at 0.416 A g-¹; (b) Cyclic voltammogram of black phosphorus-carbon composite at 0.1 mV s-1; Cycle performance... 1248

Figure II.11.B.3. (a) XRD patterns and (b) SEM images of the Pb-PbO-C composite samples prepared by SPEX mill with various milling times 1248

Figure II.11.B.4. (a) XRD and (b) initial voltage profiles of the Pb-O-C electrodes prepared in air and in Ar-filled glove box 1249

Figure II.11.B.5. (a) Cycle performance of optimized Pb-PbO-O anode in sodium half cells. Carbonate electrolytes are used and 100 mA g -1 current density was applied. Initial voltage profiles... 1249

Figure II.11.C.1. Structures of Na2Ti3O7 (left), NaTi3O6(OH)ㆍ2H₂O or NNT (middle) and lepidocrocite -type titanate AxTi2-yMyO4 (right) 1253

Figure II.11.C.2. Top left: images of a pristine carbon-free electrode containing NNT, and a carbon-free electrode discharged to 0.1V. The color change is a qualitative indicator of reduction... 1254

Figure II.11.C.3. First and second cycles of a carbon coated nanowire NNT electrode made with CMC binder (left) discharged in a sodium half cell at low rates. Cycling behavior of nanowire... 1254

Figure II.11.C.4. High-resolution TEM image of NNT dehydrated at 600℃ (left), its electron diffraction pattern (middle) and a simulated pattern for Na2Ti6O13 (right) 1255

Figure II.11.C.5. Second cycle discharge profiles of NNT heated to different temperatures (upper left) in sodium half cells. Comparison of second cycle discharge profiles of NNT heated to 500℃... 1255

Figure II.11.C.6. First and second cycle discharge profiles of Na0.7Ti1.825□0.175O4 in sodium half cells (left). Cycling data at different rates on right 1256

Figure II.11.D.1. (a) Raman spectra of EC-DMC mixed solvent and 1 M NaPF6/EC-DMC electrolyte. (b) 13C Chemical shift deduced from 13C NMR spectra of different carbonates based electrolyte 1259

Figure II.11.D.2. (a) Rate performance and (b) Coulombic efficiency of Na||HC cells (HC electrode: HC:PVDF:CB = 90:5:5; mass loading: 2-3 mg. cm-²) in 1 M NaPF6 electrolyte with different... 1260

Figure II.11.D.3. (a) Cycling stability of Na||HC cells (HC electrode, HC:binder:CB = 90:5:5; mass loading: 2-3 mg. cm-²) in 1 MNaPF6/EC+DMC electrolyte. (b) Charge profile of Na||HC cells (HC coated with alginic acid binder) 1260

Figure II.11.D.3. (a) Cycling stability of Na||HC cells (HC electrode, HC:binder:CB = 90:5:5; mass loading: 2-3 mg. cm-²) in 1 MNaPF6/EC+DMC electrolyte. (b) Charge profile of Na||HC cells... 1260

Figure II.11.D.4. (a) Molecular structure of TEP and TMP (b) Ionic conductivity of TEP:NaFSI and TMP:NaFSI (2:1) at different temperatures (c) The effect of BTFE or TTE diluent on the conductivity... 1261

Figure II.11.D.5. (a) 13C NMR spectra (b) Raman spectra of TEP-based electrolyte and with TTE or BTFE diluent 1261

Figure II.11.D.6. (a) Cycling performance at different discharge rates and (b) Charge-discharge profiles of Na||HC in phosphate-based LHCE (NaFSI:TEP:TTE= 1:2:2). The HC electrode consists... 1262

Figure II.12.A.1. (a-c) Cryo-EM images of SEI formed in 1M LiPF6 in EC/DEC without FEC on CuO nanowires at electrode potentials of (a) 0.5 V, (b) 0.0 V, and (c) below 0.0 V vs. Li/Li+. (d-f)... 1265

Figure II.12.A.2. In situ optical microscopy used to visualize the electrodeposition of Li and long-term cycling on symmetric cells. (a) The optical images of the bare Li (left column) and GF-LiF-Li (right column) interfaced with electrolyte after 0, 10, 1266

Figure II.12.A.3. (a) Comparison between model prediction and experimental voltage response for lithium symmetric cells. (b) Simulated electrode overpotentials as a function of time 1267

Figure II.12.A.4. Compare of 1st cycle of ECOPRO NMC811 vs. Li with cycled with different upper limit voltages (2.8~4.4, 4.6 and 4.8 V) at (a) room temperature (RT) and (b) 45 ℃. (c) Cycling... 1267

Figure II.12.A.5. Large scale synthesis of NMC811, showing (left) the material formed; (center) the uniformity of the "meatballs" formed, top is 20g batch and bottom is 220g batch; and... 1268

Figure II.12.A.6. Schematic of the tools Battery500 are employing to study thick electrodes 1268

Figure II.12.A.7. Abnormal d-spacing observed in NMC622 cathode material at highly charged state (〉 4.5 V). (a) Large d- spacing peak at 7 Å. (b) Neutron pair distribution function (nPDF)... 1269

Figure II.12.A.8. Cycling performances of Li||NMC811 batteries in different electrolytes (conventional electrolyte (1 M LiPF6 in EC-EMC (3:7 by wt.) with 2 wt.% of VC); dilute electrolyte... 1270

Figure II.12.A.9. SEI on Li metal anode. (a)-(c) Cryo-EM images of Li deposited on a TEM grid at different scales. Insert in (a) shows corresponding selected area electron diffraction (SAED)... 1271

Figure II.12.A.10. (Left) 1st cycle behavior of NMC811 in voltage range 2.8-4.6 V; (middle) rate capability of NMC811 with a LiBO₂/LiF coating in voltage range 2.8-4.6 V, and (right) rate... 1272

Figure II.12.A.11. a) Cycle performance of Li2S electrodes with high sulfur mass loading. (b) Voltage profiles of Li2S charging with and without quinone redox mediator. (c) Comparison of redox... 1273

Figure II.12.A.12. First cycle voltage profiles of (a) NMC622 and (b) NMC811thick electrodes with various active mass loading and porosity, at C/10, 2.8 - 4.4 V. Electrodes are provided by... 1274

Figure II.12.A.13. (a) SEM cross-section image of pristine NMC811 thick electrode, (b) PFIB large volume serial section of the thick electrode, (c) 3D reconstructed volume and phase segmentation... 1274

Figure II.12.A.14. (a) Photo of an eggplant and its cross-section morphology. (b) Schematic illustration for a carbonized EP with interconnected channel-like structure. (c) Carbonized EP after... 1275

Figure II.12.A.15. Top view SEM image of EP-LiF anode after (a) 1 cycle and (b) 10 cycles under 1 mA cm-² and 1 mAh cm-² in a symmetric cell. Top view SEM image of Li foil anode after... 1276

Figure II.12.A.16. Quantitative differentiation of inactive Li by the hydrogen evolution method. (a) Average CE of Li||Cu cells under different testing conditions. (b) Representative voltage profiles... 1277

Figure II.12.A.17. (a) Schematic of the structure of a 3D mesoporous carbon host that encourages Li wetting and pore filling. (b) Capacity retention of Li||NMC cells with cycling. NMC622 is... 1277

Figure II.12.A.18. A schematic comparison of the structure of Li-rGO (reduced graphene oxide) and Li-SirGO where the presence of silicon between the GO layers helps to maintain the gaps... 1278

Figure II.12.A.19. Microstructures of inactive Li generated in HCE (a-f) and CCE (g-l) imaged by Cryo-FIB-SEM. (a-c) and (g-i) are top view of the inactive Li at 52º tilted stage. (d-f) and (j-l)... 1278

Figure II.12.A.20. Nanostructures of inactive Li generated in HCE (a-d) and CCE (e-h) by Cryo-TEM. a, e, inactive Li morphology at low magnifications for both electrolytes. b, f, HRTEM shows... 1279

Figure II.12.A.21. Molecular design and chemical structures of SSN and derivatives. (a-c) Conceptual sketch of SSN (a), B- SSN (b), and Si-SSN (c). Blue spheres: Li+ ; orange spheres: Al;... 1280

Figure II.12.A.22. A) Cycling data for a Li/NMC622 cell developed in FY17. The cell achieved 200 cycles. B) Variation in NMC loading content from ex-situ XRD analysis following the completion... 1281

Figure II.12.A.23. Post-test Li metal electrode at the completion of 200+ cycles. Circles indicate areas of disconnected Li after cycling 1282

Figure II.12.A.24. Uneven reaction was identified by XRF (b~g) and XAS spectra (h~i) at different locations of sulfur cathodes harvested from the cycled Li-S pouch cell. ( (a) Photo image... 1282

Figure II.12.A.25. Pressure evolution over the first 28 cycles for a cell with 21 psi of external pressure applied. Similar, but more pronounced variation was observed at lower pressures which... 1283

Figure II.12.A.26. Cycle life data for a 2.5 Ah LiǁNMC cell. Cycling was at a C/10 charge and a C/3 discharge 1283

Figure II.12.A.27. Left) Differential capacity analysis on the impact of three different pressure regimes for cycling of a single layer LiǁNMC pouch cell. Right) Model framework and predicted,... 1284

Figure II.12.A.28. (a) Cycling performance of the pristine and LiF/LiBO₂-coated NMC811 cathodes. Selected charge-discharge curves of (b) the pristine and (c) LiF/LiBO₂-coated NMC811... 1285

Figure II.12.A.29. The electrochemical analytical diagnosis (eCAD) technique revealed (a) the attributes to the capacity fade of an early failed Li | standard electrolyte | NMC622 coin cell and... 1286

Figure II.12.B.1. (a) Nyquist plot of Au interface engineered Li/LLZO/Li cell. (b) DC cycling of Au interface engineered Li/LLZO/Li cell with a step current of 20 μA cm-² starting from 20 μA cm-².... 1300

Figure II.12.B.2. Fracture surface SEM micrographs of green tapes freeze tape cast from slurries containing (a) 7.5 vol.% LLZO / 400 μm, (b) 10 vol.% LLZO / 220 μm, and (c) 10 vol.% LLZO /... 1301

Figure II.12.B.3. (a) Optical image of cathode infiltrated LLZO bilayer. Cathode infiltrated porous layer surface (left) and dense layer surface (right) are shown. (b) SEM fracture surface image... 1301