化金属有机框架用于提高离子电池中高阴极的性能
Heeju Ahn1, Yeonju Park1, Kwan Woo Nam1
1Department of Chemical Engineering and Materials Science, and Graduate Program in System Health and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea.
ChemSusChem
|August 22, 2024
概括
含有化剂的金属有机框架通过改善离子转移和减少金属交叉声来提高离子电池的性能. 这些添加剂提高了高阴极的能量密度和稳定性.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 离子电池 (LIB) 对便携式电子产品,电动汽车和电网存储至关重要.
- 高 (Ni) 阴极,如LiNixCoyMnzO2 (NCM,x≥0.8),提供高能量密度,但面临挑战.
- 关键的限制包括缓慢的离子转移速率和过渡金属 (TM) 迁移到阳极,阻碍性能.
研究的目的:
- 调查金属有机框架 (MOF) 与合剂作为NCM阴极的添加剂的使用.
- 为了应对有限的离子动力学和TM交叉交谈在高Ni LIB中的挑战.
- 为了提高NCM阴极的电化学性能和稳定性.
主要方法:
- 在电极配方中将MOF与合剂作为添加材料的结合.
- MOF属性的表征:TM交叉谈话缓解,Li+部分溶解和离子固定.
- 修改NCM阴极的电化学测试,包括原始和循环后性能评估.
主要成果:
- 化MOF修改显著降低了NCM阴极中的电荷传输电阻.
- 在修改后的NCM阴极中,在100个循环后观察到改善的离子扩散系数.
- MOFs有效地减轻了TM向阳极的迁移,并促进了Li+离子转移.
结论:
- 含有合剂的MOF是提高LIB性能的有效添加材料.
- 这项研究展示了一种可行的策略,以克服高能量密度NCM阴极的动力限制.
- 这种方法对推动下一代离子电池的发展具有重大前景.
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