抑制维尼利丁化基聚合物电解质中的残留溶剂诱导的副作用,使得超稳定的固态金属电池成为可能
Dechao Zhang1,2, Yuxuan Liu3, Shuo Yang1
1Hong Kong Center for Cerebro-Cardiovascular Health Engineering (COCHE), City University of Hong Kong, Shatin N. T., Kowloon, Hong Kong SAR, 999077, China.
Advanced materials (Deerfield Beach, Fla.)
|May 13, 2024
概括
一种新的溶剂2,2,2-trifluoro-N,N-dimethylacetamide (FDMA) 增强了金属电池的固体聚合物电解质 (SPEs). 这一创新提高了离子导电性和电极稳定性,使电池寿命更长.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 聚合物科学 聚合物科学
背景情况:
- 已知基于乙烯基化物 (VDF) 的固体聚合物电解质 (SPEs) 中的残留溶剂可增强离子导电性.
- 然而,这些溶剂可能会与 (Li) 金属产生有害的副作用反应,导致电池稳定性不佳.
- 这种不稳定性一直是基于VDF的SPE开发中的一个重大,但经常被忽视的挑战.
研究的目的:
- 开发一种策略来平衡基于VDF的SPE中的离子导电和电极稳定性.
- 引入一种新的无侧反应溶剂,提高电化学稳定性.
- 为了使高性能金属电池具有增强的寿命.
主要方法:
- 开发2,2,2-trifluoro-N,N-dimethylacetamide (FDMA) 作为基于聚乙烯化物-联合化 (PVHF) 的SPEs的溶剂.
- 研究FDMA溶剂和金属之间的接口反应,以形成稳定的固体电解质接口相 (SEI).
- 在苛刻的条件下,对立式电池和LiFePO4和LiCoO2电池电池的电化学测试.
主要成果:
- 开发的FDMA溶剂促进了稳定的SEI层,有效地抑制了副作用和树的生长.
- 使用FDMA的基于PVHF的SPEs具有高离子导电性和显著改善的电化学稳定性.
- 证明了在Li有氧化对称电池和Li有氧化FePO4电池中卓越的循环性能,即使使用薄型Li金属和高负荷阴极.
- 在4.48V的高切断电压下,在Li的LiCoO2电池中实现了稳定的运行,证实了高压稳定性.
结论:
- 对于基于VDF的SPEs,FDMA是一种高效的无侧反应溶剂,对于稳定的金属电池至关重要.
- 该战略成功地平衡了离子传输和电极接口稳定性,克服了以前的局限性.
- 这项工作为开发下一代高能耗和持久金属电池的先进SPE提供了途径.
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