解决容量/电压衰减和相位过渡之间的关系,通过加快分层到旋转过渡加速相位过渡
Qi Pang1, Mengke Zhang1, Yang Song1
1School of Chemical Engineering, Sichuan University Chengdu 610065 China qiulang2023@scu.edu.cn xiaodong2009@163.com.
Chemical science
|February 6, 2025
概括
用FeF3涂层丰富的阴极材料显著改善了离子电池的容量保留和电压稳定性. 这种修改将容量退化与电压衰减脱,提高了电池的性能.
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:
- 富含的阴极材料为离子电池提供高能量密度.
- 商业化受限于循环期间严重的电压和容量退化.
- 提高电压和容量保留对于先进的电池开发至关重要.
研究的目的:
- 调查丰富的阴极材料中电压和容量降解之间的关系.
- 通过表面修改,提高丰富的正极材料的循环稳定性.
- 探索相位转换对电化学性能的影响.
主要方法:
- 在特定的晶体平面上用FeF3涂层丰富的阴极材料.
- 电化学循环和性能分析 (容量保留,电压衰减).
- 在电池循环期间分析相位转换.
主要成果:
- FeF3涂层导致显著改善容量保留 (97%与200个循环后的75%相比).
- 涂层和原始材料之间的电压衰变是可比的,尽管涂层样品的相变更为激烈.
- 发现容量降低和电压衰减是独立的过程.
结论:
- 用FeF3修改表面有效地提高了丰富的阴极材料的稳定性.
- 该研究表明,循环期间的相位转换不一定与增加的电压衰减相关.
- 结果提供了关于解能力和电压降解的见解,适用于其他阴极系统.
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