Fluorinated Ether Additives as Efficient F-Source for Stabilizing Li Metal Interface in Carbonate- based Electrolyte
- 발행기관 서강대학교 일반대학원
- 지도교수 장지현
- 발행년도 2026
- 학위수여년월 2026. 2
- 학위명 석사
- 학과 및 전공 일반대학원 화학과
- 실제URI http://www.dcollection.net/handler/sogang/000000082782
- UCI I804:11029-000000082782
- 본문언어 영어
- 저작권 논문은 저작권에 의해 보호받습니다.
초록(요약문)
Fluorine-rich interphases are widely regarded as beneficial for Li metal anodes, yet achieving stable cycling in carbonate electrolytes remains challenging as LMB conditions become increasingly stringent. In this work, we investigate fluorinated ether (FE) additives as efficient F-sources in a conventional LiPF6/carbonate electrolyte containing LiPO2F2 and FEC, and evaluate their effectiveness using a stepwise screening protocol that progressively tightens cell configurations from baseline conditions toward Li-inventory limited full cells. Electrochemical tests demonstrate that FE additives suppress polarization growth and stabilize Li plating/stripping, while also mitigating relaxation “tail” evolution in Li‖Li symmetric cells, implying reduced dead-Li accumulation and alleviated transport limitations during rest. Although the Zhang-method average CE values are comparable among the evaluated electrolytes (≈ 98.1–98.3%), FE-containing systems exhibit more persistent stability under Li-inventory limitation, suggesting improved robustness of Li deposition/stripping kinetics under harsher conditions. Mechanistic analyses using dQ/dV, 19F NMR, and XPS support preferential FE reduction and the formation of an SEI enriched with inorganic species such as LiF and Li2O. Notably, the T-type FE remains effective in thin-Li full cells, delivering markedly improved capacity retention relative to the baseline electrolyte under identical operating conditions. Overall, FE additives provide a compatibility-friendly approach to enhance Li metal reversibility in carbonate-based electrolytes and represent an intermediate stepping stone toward practical LMBs, which will ultimately require the combined realization of lean electrolyte, high-loading cathodes, and thin Li metal anodes.
more목차
List of Tables 6
List of Figures 7
Abstracts 10
1. Introduction 12
2. Experimental Sections 14
2.1 Electrolyte preparation 14
2.2 Electrode preparation 14
2.3 Coin cell fabrication 15
2.4 Electrochemical measurements 16
2.5 Characterization 17
3. Results and Discussion 19
3.1. Interfacial activity on lithium metal with additives 19
3.2 Reduction behavior and bulk transport properties of FE additives 33
3.3 Electrochemical performance with Ni-rich cathode cells 44
4. Conclusion 53
5. Reference 60
