长距离离子干扰提高了富含的多层阴极的综合性能
Maolin Yang1, Tingting Yang1,2, Mingjie Dong1
1School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen, 518055, China.
Advanced materials (Deerfield Beach, Fla.)
|May 9, 2025
概括
破坏离子电池 (SIB) 富含层氧化物 (MRLOs) 中的阳离子排序可减轻结构不稳定性,并增强离子扩散. 这种方法改善了可持续电池应用的容量保留和能量密度.
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:
- 富含的分层氧化物 (MRLOs) 是用于离子电池 (SIB) 的成本效益高的阴极材料.
- 挑战包括由于Mn氧化还原潜力的低能量密度和围绕Mn3+的Jahn-Teller扭曲造成的结构不稳定.
- 在MRL中复杂的阴离子排序阻碍了离子 (Na+) 迁移.
研究的目的:
- 在MRL中发现新的阴离子排序结构.
- 为了减轻Jahn-Teller扭曲和增强Na+扩散动力学.
- 为了提高SIB阴极的电化学性能.
主要方法:
- 调节氧气空位的形成,以扰乱阳离子的排序.
- 使用最大透法 (MEM) 对中子衍射数据的分析.
- 研究半电池配置中的电化学性能.
主要成果:
- 长距离离子排序的破坏有效地缓解了合作的Jahn-Teller扭曲.
- 在8C的1000个循环中实现了95.3%的容量保留.
- 优化的Na+扩散路径和动力学被可视化.
- 升高的Mn4+/Mn3+氧化还原潜力导致竞争力的能量密度为626 Wh kg-1 (1.5-4.5 V).
结论:
- 破坏远程阴离子排序是优化离子阴极的可行策略.
- 这种方法增强了结构稳定性和Na+扩散.
- 电化学性能,包括能量密度和循环寿命的显著改善被证明.
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