在离子电池的常规分层氧化物阴极中重新评估离子氧化还原:离子和共价机制
Jianhua Yin1, Zixin Wu1, Kai Fang1
1State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University Xiamen 361005 P. R. China zixinwu_gz@163.com yuqiao@xmu.edu.cn.
Chemical science
|April 11, 2025
概括
高--氧化物 (NCM) 阴极显示氧气二元化和被困的O2在高电压下,与低版本不同. 这导致结构不稳定,影响离子电池的能量密度.
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:
- 为了提高能量密度,改进,,氧化物 (NCM) 阴极需要使用高电压或增加含量.
- 了解收费补偿机制对于这些进步至关重要.
- 传统模型未能捕捉到阴离子氧化还原和金属氧相互作用的重要作用.
研究的目的:
- 在高压条件下,系统地研究低和高NCMs的电荷补偿过程.
- 阐明氧气在氧化还原反应中的关键作用及其与过渡金属的相互作用.
- 为了将氧气行为与结构稳定性和元素组成相关联.
主要方法:
- 在NCM中对费用补偿进行系统调查.
- 分析涉及过渡金属和氧气的氧化还原过程.
- 氧气二分化与结构和组成因素的相关性.
主要成果:
- 氧气起着关键的氧化还原作用,与过渡金属 (TMs) 形成强有力的共价键.
- 高NCM表现出氧气二元化与被困的O2,而不是低对应物.
- 高NCM中的氧气二元化导致空缺聚合和结构不稳定.
结论:
- 氧氧还氧化行为显著影响NCM的性能和稳定性.
- 氧二分化的差异与元素组成,旋转状态和堆叠故障相关.
- 优化氧氧还氧反应是开发高容量,高能量密度的离子电池的关键.
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