消除原生缺陷和强化格子框架,以实现超稳定的离子层状阴极
Jiangnan Huang1, Lei Sun1, Xinyi Pan1
1State Key Laboratory of Powder Metallurgy, College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P.R. China.
Advanced materials (Deerfield Beach, Fla.)
|June 10, 2025
概括
层层的过渡金属氧化物 (TMO) 阴极表面上的原生缺陷会导致降解. 表面修复和La引入强化颗粒,提高离子电池的性能和稳定性.
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
- 固态化学 固态化学
背景情况:
- 多层过渡金属氧化物 (TMO) 阴极对于离子电池至关重要.
- 退化通常与相位过渡有关,忽视了原生缺陷.
- 表面改造和缺陷显著影响阴极性能.
研究的目的:
- 研究原生表面缺陷在P2型Na2/3Ni1/3Mn2/3O2阴极降解中的作用.
- 了解表面改造如何有助于产能减弱.
- 制定策略,通过解决表面缺陷来减轻降解.
主要方法:
- 使用了通用的功能密度计算.
- 采用了 ex-situ 硬X射线吸收光谱.
- 实现了用梯度进行缺陷剥离和修复的介绍.
主要成果:
- 确定了粒子表面上的格子不匹配和元素扭曲,导致低价值TM积累.
- 证明缺陷积累,而不是相位过渡,是主要的降解驱动因素.
- LaO6配置稳定了TMO6框架,抑制了低价值TM的形成.
结论:
- 表面纠正和加强的阴极颗粒显著提高了电化学性能.
- 达到高容量保留 (98%在2C时超过500个周期,87%在10C时超过4000个周期).
- 在广泛的温度范围 (-20°C至60°C) 中表现出稳定的性能.
相关概念视频
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