+溶解结构对腐蚀在以为基础的电解质溶液与二硫胺 (LiFSI) 的影响
Taegyu Jang1, Seon Yeong Cho1, Jaegeol Kim2
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, South Korea.
Small (Weinheim an der Bergstrasse, Germany)
|February 16, 2025
概括
像FDMB这样的乙烯溶剂通过促进保护性AlF3的形成和抑制可溶性Al3+物种来防止电池中的腐蚀. 这在极端条件下提高了电池的稳定性.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 电池技术 电池技术
背景情况:
- 二 (硫) 胺 (LiFSI) 对于金属电池中稳定的固体电解质间相 (SEI) 形成至关重要.
- 然而,单靠LiFSI无法保护电流采集器免受腐蚀,导致性能降低.
- 了解溶剂对腐蚀的影响对于先进的电池开发至关重要.
研究的目的:
- 研究化溶剂在基于LiFSI的电解质中减轻腐蚀的机制.
- 阐明离子溶解和离子配对结构在防止Al3+溶解中的作用.
- 确定最佳的溶剂结构,以提高电流收集器的稳定性.
主要方法:
- 用各种以太溶剂 (FDMB,DME/TTE,TEGDME) 在1米LiFSI中对腐蚀进行电化学分析.
- 密度函数理论 (DFT) 计算用于研究离子溶解和脱机制.
- 在极端条件下评估电池性能 (4.5V,60°C).
主要成果:
- 2,2,3,3-四-1,4-二甲基 (FDMB) 有效地防止了的腐蚀,并促进了AlF3的形成.
- 由于FDMB与Li+和Al3+的有利脱,以及聚合的Li+-FSI−离子对抑制了可溶性Al3+物种.
- 非化乙烯和DME/TTE显示腐蚀增加,原因是溶解和脱效率较低.
结论:
- 化以太溶剂,特别是FDMB,在LiFSI电解质中提供了对腐蚀的显著保护.
- 阴离子溶解和离子配对是缓解Al3+溶解和提高电池稳定性的关键因素.
- 优化溶剂设计可以导致更耐用和高性能金属电池.
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