揭示LiTFSI沉作为基于的盐水电解质中固体电解质相间形成的关键因素
Rossukon Jommongkol1, Siraprapha Deebansok1, Jie Deng2
1Molecular Electrochemistry for Energy Laboratory, School of Energy Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand.
Small (Weinheim an der Bergstrasse, Germany)
|September 13, 2023
概括
研究人员探索了离子电池的盐水电解质. 他们发现固体电解质间相 (SEI) 层含有沉的LiTFSI,并且具有动态性,影响电池性能.
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
背景情况:
- 盐中的水电解质 (WiSE) 为离子电池提供了更广泛的电化学稳定性窗口.
- 在WiSE中的高盐度降低了水的活性,抑制了分解.
- 在利用WiSE以提高能量密度和循环稳定性方面,由于诸如进化等寄生反应,仍然存在挑战.
研究的目的:
- 调查WiSE中的固体电解质介相 (SEI) 层的组成和行为.
- 了解LiTFSI沉在SEI形成中的作用.
- 在电池运行期间分析SEI层的动态性质.
主要方法:
- 使用高分辨率光学显微镜观察SEI形成.
- 电化学分析以研究进化反应.
- 化学分析用于识别SEI组件.
主要成果:
- 观察到一个微米白色层,被确定为SEI的组成部分.
- 证实了LiTFSI沉是SEI层内的主要物种.
- 该SEI层表现出动态行为,在开放电路电压期间溶解回电解质.
结论:
- WiSE中的SEI层不仅仅是纳米级,还含有LiTFSI沉物.
- 包括其溶解在内的SEI层的动态性质是电池性能的一个关键因素.
- 了解SEI动态对于优化离子电池中的WiSE至关重要.
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