格子平面化使富含的多层阴极的晶体结构变平
Pengcheng Li1,2, Zhuo Peng1,3, Zhihao Sun4
1Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing, 100193, China. yongjin.chen@hpstar.ac.cn.
Materials horizons
|July 24, 2025
概括
一个新的格子平面化策略增强了富含的,,和氧化 (NCM) 电气汽车的阴极. 这种方法提高了结构稳定性,并且在快速充电期间显著提高了容量保留,从而使电池寿命更长.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 富含的,,,氧化 (NCM) 阴极因结构缺陷和缓慢的离子扩散而面临快速容量衰减,阻碍快速充电应用.
- 网格应变,机械故障和界面反应进一步加快高NCM材料的降解.
- 现有的NCM阴极表现出不良的循环稳定性,限制了它们在电动汽车等苛刻应用中的使用.
研究的目的:
- 研究一种新型格子平面化 (LP) 策略的有效性,以提高高NCM阴极的电化学性能和结构稳定性.
- 通过晶格工程来增强离子扩散动力学和减轻NCM材料中的降解机制.
- 展示一种用于制造先进电池技术无缺陷,高性能NCM阴极的实用方法.
主要方法:
- 使用湿化学和烧焦方法将 (Al) 和 (Zr) 引入NCM的过渡金属层.
- 这个过程简化了复杂的格子结构,创造了一个有序的阶段,并修复了NCM材料中的缺陷.
- 电化学测试,包括高频率 (5C和1C) 的循环测试,在修改后的LP-NCM阴极和囊细胞上进行.
主要成果:
- 经过修改的LP-NCM阴极在5C下完成了300个循环后,实现了157.3 mAh g-1的高初始放电容量和81%的容量保留,超过原始NCM (50.9%).
- LP-NCM/石墨袋式电池表现出极好的循环稳定性,在1C的1000个循环中保持80%的容量.
- 该LP策略有效地消除了不必要的阶段,抑制了各种空缺 (氧气,,过渡金属),并最大限度地减少了Li/Ni的混合,导致循环后的纳米孔状结构而不是裂.
结论:
- 格子平面化策略显著提高了高NCM阴极的结构完整性和电化学性能.
- 这种方法有效地解决了关键的降解问题,包括缓慢的离子扩散,结构不稳定性和机械故障.
- 通过LP策略进行格子工程,为开发下一代高性能储能应用的正极材料提供了一个有前途的途径.
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