리튬 메탈 배터리를 위한 고체 고분자 전해질의 이온 수송 메커니즘 이해

다국어 초록 (Multilingual Abstract)

The development of all-solid-state batteries (ASSBs) is promising next-generation energy storage device, which has high energy density and remarkable safety performance. For designing superior ASSBs, solid-state polymer electrolytes (SSPEs) that exhibit high ionic conductivity and mechanical properties are indispensable component. However, for the ASSB practical applications, there are still some issues to overcome, such as poor interfaces between the SPEs and both cathode and anode electrodes.
In this study, we prepared two different SPEs: silica aerogel-based nanocomposite SSPEs and lithium acrylate-based hydrogel SSPEs. The silica aerogel-based SSPEs are silica aerogel reinforced single-Li^+ conducting polymer electrolytes, where anions are covalently attached to silica aerogels, thereby reducing anion mobility and consequently achieving high lithium transference number. Also, lithium metal batteries with a silica aerogel-based SSPEs exhibit excellent lithium metal battery performances which present 97 % capacity retention and 100 % coulombic efficiency after 75 cycles at 1 C. The lithium acrylate hydrogel SSPEs, crosslinked with vinyl functionalized Al2O3 (VAl2O3), exhibit high ionic conductivity of ~ 10^(-2) S/cm at room temperature and high surface charge density, and both characteristics enable to increases energy storage performances.
For the possible SSPEs, their ion conductivities, mechanical properties, thermal stabilities, and morphology were systematically investigated using various analysis methods. Consequently, this study should provide insight into the design of next-generation energy storage devices.

목차 (Table of Contents)

• Chapter Ⅰ. Introduction 1
• Ⅰ-1. Introduction of Solid Polymer Electrolytes 1
• Ⅰ-1.1 Dual-Ion Polymer Electrolytes & Single-Ion Polymer Electrolytes 2
• Ⅰ-1.2 Energy Storage Devices 3
• Ⅰ-2. Background 5
• Ⅰ-2.1 Ion Conduction Properties 6
• Ⅰ-2.2 Dielectric Relaxation Properties 9
• Ⅰ-3. References 11
• Chapter Ⅱ. Fast Li+ Transport via Silica Network-Driven Nanochannels in Ionomer-inFramework for Lithium Metal Batteries 13
• Ⅱ-1. Introduction 13
• Ⅱ-2. Experimental Section 17
• Ⅱ-2.1 Materials 17
• Ⅱ-2.2 Synthesis of Silica Aerogel (SA) 17
• Ⅱ-2.3 Preparation of Lithium Acrylate Monomer (LiA) 18
• Ⅱ-2.4 Synthesis of Lithium 1-[3-(methacryloyloxy)-propylsulfonyl]-1-(trifluoromethylsulfonyl)imide (LiMTFSI) 18
• Ⅱ-2.5 Synthesis of Lithium 4-styrenesulfonyl(trifluoromethylsulfonyl)imide (LiSTFSI) 19
• Ⅱ-2.6 Synthesis of Aqueous-Based SANPEs: P(LiA)-SANPE, [P(LiA)-PEG (1:1)]-SANPE, and P(AA)-SANPE 20
• Ⅱ-2.7 Synthesis of Nonaqueous-Based SANPEs: P(LiMTFSI)-SANPE, P(LiSTFSI)-SANPE, and [P(LiMTFSI)-PEG (1:1)]-SANPE 21
• Ⅱ-2.8 Lithium Metal Battery Fabrication 25
• Ⅱ-2.9 Characterization 25
• Ⅱ-3. Result and Discussion 26
• Ⅱ-3.1 SANPE Synthesis 26
• Ⅱ-3.2 SA Grafted with Anions Probed by ATR-FTIR and TGA 26
• Ⅱ-3.3 Network Morphology Confirmed by FE-SEM, BET, and Rheology 36
• Ⅱ-3.4 Lithium Ionic Conductivity 50
• Ⅱ-3.5 Lithium Transference Number and Electrochemical Stability 52
• Ⅱ-3.6 Electrochemical Performance of LMB 58
• Ⅱ-4. Conclusions 68
• Ⅱ-5. References 70
• Chapter Ⅲ. The Effect of Inorganic Nanoparticles on Ion Conduction in Poly(lithiumacrylate)-based Composite Polymer Electrolytes for Energy Storage Devices 79
• Ⅲ-1. Introduction 79
• Ⅲ-2. Experimental Section 80
• Ⅲ-2.1 Materials 80
• Ⅲ-2.2 Synthesis of vinyl functionalized Al2O3 and AALi monomer 80
• Ⅲ-2.3 Preparation of poly(lithium acrylate)-based CPE 80
• Ⅲ-2.4 Characterization 81
• Ⅲ-3. Result and Discussion 83
• Ⅲ-3.1 Mechanical Properties 83
• Ⅲ-3.2 Ionic Conductivity 85
• Ⅲ-3.3 Dielectric Properties 87
• Ⅲ-4. Conclusions 90
• Ⅲ-5. References 91
• Appendix A Ion-Cluster-Mediated Ultrafast Self-healable Ionoconductors for Reconfigurable Electronics 92
• A-1. Characterization 92
• A-2. Results and Discussion 93
• A-2.1 Static Dielectric Constant 93
• A-2.2 Dielectric Relaxation 95
• A-3. References 99
• Appendix B Ion Transport through Layered Hydrogels for Low-Frequency Energy Harvesting toward Self-Powered Chemical Systems 100
• Appendix C Augmented Thrust-Force Mechanotransducer for Faster Soft Robot 102
• C-1. Results and Discussion 102
• C-2. References 108