稳定表面格子On- (0 < n < 2) 为LiCoO2的长期耐用性提供稳定
Wenguang Zhao1, Mingyang Li2, Zijian Li3
1School of Advanced Materials, Peking University Shenzhen Graduate School Shenzhen, Shenzhen, 518055, P.R. China.
Angewandte Chemie (International ed. in English)
|March 28, 2025
概括
用岩盐相对氧化氧化 (LCO) 的表面修饰稳定了晶格氧气,提高了先进电池阴极的长期循环稳定性.
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
- 表面化学 表面化学
背景情况:
- 在4.55V以上的充电氧化物 (LCO) 中,表面晶格氧 (On−) 的不稳定性限制了循环稳定性.
- 降解涉及表面旋转相转化为+阻断相.
研究的目的:
- 通过构建螺旋 (S-LCO) 和岩盐 (R-LCO) 阶段来稳定表面格子在LCO中的On−.
- 为了提高LCO阴极的长期循环稳定性和高压性能.
主要方法:
- 在LCO的表面工程中,通过创建螺旋和岩盐相.
- 在4.6V的长期循环测试中.
- 氧气迁移障碍物的理论计算.
主要成果:
- 岩盐相 (R-LCO) 表面格子On−在循环过程中保持稳定.
- 理论计算显示,岩盐阶段的On−迁移障碍较高.
- 在以4.6V (1C) 进行1000个循环后,R-LCO水电池实现了78.6%的容量保留,并显示出卓越的浮动电荷耐用性.
结论:
- 稳定表面格子On−对于高压LCO阴极性能至关重要.
- 岩盐相表面修改有效地提高了LCO稳定性和循环寿命.
- 表面结构定制是开发先进LCO阴极的关键策略.
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