在丰富的氧化物层正极中结构降解的起源
Tongchao Liu1, Jiajie Liu2, Luxi Li3
1Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA.
Nature
|June 8, 2022
概括
富含和 (LMR) 阴极的电压衰变是由纳米电流和晶格位移驱动的. 这项研究揭示了这些影响导致降解和氧气损失, 阻碍了电池的能量密度和商业化.
科学领域:
- 材料科学
- 电化学
- 能量储存
背景情况:
- 和丰富的 (LMR) 阴极材料通过阴离子和阴离子还氧化提供高能量密度.
- 在LMR阴极中的电压衰变阻碍了商业化,其根本原因尚不清楚.
研究的目的:
- 确定LMR阴极材料中电压衰变背后的驱动力.
- 研究纳米流,格子位移和材料降解之间的关系.
主要方法:
- 在位纳米级敏感的连贯X射线衍射成像.
- 在多个结构层面 (原子,粒子,电极) 进行微至宏长度的表征.
主要成果:
- 在 LMR 阴极运行过程中,纳米线和晶格位移积累.
- 这些影响被认为是结构降解和氧气损失的主要驱动因素.
- 在LMR阴极的异质性加剧了应变和位移,不受传统方法的影响.
结论:
- 格子的应变和位移是导致LMR阴极电压衰变的关键因素.
- 半结构设计被认为是缓解这些问题的可行策略.
- 通过确保稳定的电压和容量,这些发现为商业化LMR阴极材料铺平了道路.
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