通过纳米尺度成像检测单晶液态COO2中的域边界诱导的结构降解
Hongyi Pan1,2, Sichen Jiao1,2,3, Yanshuai Hong1,2,3
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.
ACS nano
|July 18, 2025
概括
单晶阴极含有隐藏的纳米级域边界,导致降解. 控制这些内部结构是提高离子电池性能的关键.
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
- 纳米技术纳米技术
背景情况:
- 高容量阴极材料对于先进的离子电池至关重要.
- 单晶阴极是首选的,但可能含有缺陷.
- 了解单晶中的降解机制至关重要.
研究的目的:
- 调查单晶LiCoO2阴极中纳米尺度缺陷的存在和影响.
- 阐明这些缺陷在电池退化中的作用.
- 确定增强正极稳定的策略.
主要方法:
- 超分辨率纳米级X射线计算机断层扫描 (纳米CT).
- 扫描探头纳米衍射成像 (SPNDI).
- 先进的数据驱动的统计分析.
- 电化学性能测试,电化学性能测试.
主要成果:
- 在LiCoO2单晶体内确定了无处不在的纳米级域边界.
- 这些边界作为应变积累和微裂纹形成的热点.
- 边界的残余应变加快了不可逆转的相位过渡.
结论:
- 颗粒内域边界显著影响机械和电化学降解.
- 有针对性的兴奋剂可以稳定这些关键接口.
- 在下一代高能量密度电池中,颗粒内部域调节是必不可少的.
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