测试LiCoOO的降解情况
Guozhong Lu1, Fushan Geng1, Nianrui Guo1
1Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, P. R. China. mshen@phy.ecnu.edu.cn.
Chemical communications (Cambridge, England)
|June 6, 2023
概括
在高压操作过程中,氧化 (LiCoO2) 阴极降解为旋转相,导致离子电池的容量损失. 了解这种转变是改善电池寿命的关键.
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
- 固态化学 固态化学
背景情况:
- 在高压离子电池中,氧化 (LiCoO2) 的长期循环稳定性仍然是一个重大挑战.
- 驱动这些电池容量衰减的精确机制尚未完全阐明.
研究的目的:
- 在高压条件下的长期循环过程中研究LiCoO2阴极的相变.
- 为了确定使用LiCoO2阴极的离子电池容量减弱的主要原因.
主要方法:
- 使用了17O魔形旋转角核磁共振 (MAS NMR) 光谱.
- 从液态和固态电池单元中分析循环LiCoO2阴极材料.
主要成果:
- 在循环后观察到LiCoO2阴极材料的显著相变.
- 确定了旋转相的形成作为主要的降解途径.
- 与观察到的容量衰退相关联了这种螺旋相变化.
结论:
- LiCoO2 退化到旋转阶段是导致高压运行过程中产能损失的主要机制.
- 17O MAS的NMR光谱是一种有效的工具,用于探测阴极材料的转变.
- 研究结果为开发更稳定的高压阴极材料提供了关键的见解.
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