走向长寿命的高压水性离子电池:从溶解化学到固体电解质相间层优化,对抗电子道效应
Insu Jeong1, Sungho Kim1, Youngbi Kim2
1Department of Chemistry, Pohang University of Science and Technology (POSTECH), 37673, Pohang, Republic of Korea.
Advanced materials (Deerfield Beach, Fla.)
|December 27, 2024
概括
研究人员通过控制溶解和优化固体电解质相间层 (SEI) 开发了一种用于高压离子电池的新型水性电解质. 这提高了稳定性和循环寿命,从而实现更安全,高性能的能量存储.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 水性电解质比有机溶剂具有非易燃性的优势,但受到有限的电化学稳定性窗口 (ESW) 的影响.
- 溶解化学设计对于抑制水的反应性和在水性电解质中扩大ESW至关重要.
- 优化固体电解质相间层 (SEI) 层对于稳定的电池性能至关重要.
研究的目的:
- 扩大用于高压离子电池的水性电解质的电化学稳定性窗口 (ESW).
- 改善水性离子电池的初始容量保留和长期循环稳定性.
- 调查溶解结构和SEI层优化对电池性能的综合影响.
主要方法:
- 开发了一种以乙胺为基础的三元欧电解质,以限制水分子并破坏结合.
- 通过扩大工作电压范围以优化SEI形成,诱导了额外的进化反应.
- 分析了SEI层的组成和结构,重点关注LiF含量和密度.
主要成果:
- 通过新型电解质实现了1.4至5.1V的扩展ESW.
- 优化了SEI层的形成,导致更密集,富含LiF的层,防止水分解.
- 经过1000个循环 (116 mAh g−1) 后,表现出改善的循环稳定性,76%的容量保留.
结论:
- 溶解结构的修改和SEI层的优化对于高压水性离子电池至关重要.
- 开发的电解质和SEI战略显著提高了电池的性能和稳定性.
- 这种方法为更安全,更高效的水性能源存储系统铺平了道路.
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