Development of anode materials based on liquid and solid electrolytes for interfacial stabilization of lithium metal batteries

다국어 초록 (Multilingual Abstract)

Lithium metal is widely considered the most promising anode for next-generation rechargeable batteries owing to its ultrahigh theoretical specific capacity (3860 mAh g-1) and the lowest redox potential (−3.04 V vs. SHE). However, the practical deployment of lithium metal batteries remains significantly constrained by severe interfacial instability at the Li anode. To address these interfacial limitations, we has focused on surface engineering of the Li anode to control interfacial structure and improve electrochemical stability. First, in liquid electrolyte based lithium metal batteries, we engineered the copper current collector surface using fluorine-nitrogen doped carbon, which promotes the in situ formation of a robust LiF-rich SEI layer. This approach leads homogeneous lithium deposition, and preserves the high energy density of the cell while extending cycle life. Second, in solid-state batteries employing sulfide electrolytes, we constructed a double-layer interfacial structure consisting of a lithiophobic LiCl top layer and a lithiophilic Li–Al alloy underlayer on the Li metal surface. The LiCl layer acts as an electronic insulator that blocks electron transfer and suppresses side reactions with the sulfide electrolyte, while the Li–Al alloy enhances wettability and facilitates Li⁺ transport kinetics at the anode/SSE interface. The synergistic function of double layer delivers remarkable long-term cycling stability.

목차 (Table of Contents)

• Chapter 1. Introduction 1
• 1.1. Lithium metal battery 1
• Chapter 2. Fluorine–Nitrogen Co-Doped Carbon Host for Horizontal Lithium Growth with Lithium Fluoride-Rich Solid Electrolyte Interphase in Lean-Lithium Batteries 2
• 2.1. Introduction 3
• 2.2. Experimental 6
• 2.2.1. Synthesis of NC and FNC 6
• 2.2.2. Characterizations 6
• 2.2.3. Electrochemical measurements 7
• 2.2.4. Computational method 8
• 2.3. Results and discussion 9
• 2.3.1. Synthesis and Structural Characterization of FNC 9
• 2.3.2. Structural and Chemical Characterization of NC and FNC 12
• 2.3.3. Morphological Analysis of Lithium Deposition 18
• 2.3.4. DFT Calculations Elucidating Lithiophilicity Enhancement 28
• 2.3.5. Performance and Interfacial Stability of FNC Hosts 33
• 2.3.6. Symmetric Cell Performance in Long-Term Stability 42
• 2.3.7. Full-Cell Performance 45
• 2.3.8. Characterization of after cycled FNC hosts 53
• 2.4. Conclusion 58
• Chapter 3. AlCl3-Engineered Dual Interphase for Stable Li/LPSCl interfaces in High-performance Solid-State Lithium Metal Batteries 59
• 3.1. Introduction 60
• 3.2. Experimental 63
• 3.2.1. Synthesis of LiAlCl anode 63
• 3.2.2. Characterizations 63
• 3.2.3. Electrochemical measurements 64
• 3.2.4. Measurement of electronic conductivity and activation energy 65
• 3.3. Results and discussion 66
• 3.3.1. Optimization of the Coating Solution 66
• 3.3.2. Characterization of the LiAlCl 70
• 3.3.3. Electrochemical property of LiAlCl anode for ASSLMBs 75
• 3.3.4. Performances of LiAlCl ASSLMBs cell tests 78
• 3.3.5. Post-cycling characterization of LiAlCl anode 84
• 3.4. Conclusions 87
• Bibliography 88
• Curriculum Vitae 108