通过将氧气空隙和表面化相结合,提高多层丰富阴极的循环可逆性
Aierxiding Abulikemu1, Toshiyuki Matsunaga1, Xian Shi1
1Graduate School of Human and Environmental Studies, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
ACS applied materials & interfaces
|November 15, 2023
概括
研究人员通过修改分层类型的丰富的阴极材料来提高离子电池的性能. 表面化和氧气空缺的引入提高了下一代能源存储的容量保留和循环稳定性.
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:
- 丰富的阴极材料为离子电池提供高容量.
- 由于氧氧还氧化活性和表面退化,循环可逆性差,限制了它们的应用.
- 表面修改对于增强阴极材料稳定性至关重要.
研究的目的:
- 为了抑制丰富的阴极材料的表面降解.
- 为了提高丰富阴极的循环性能和容量保留.
- 探索一种新的策略,利用的加入来修改阴极材料.
主要方法:
- 合成的丰富的阴极材料是Li 1.2Ni 0.2Co 0.2Mn 0.4O 2. 在这种材料中,含量高于含量.
- 使用CaH2作为减少剂引入氧气空缺.
- 使用NH 4HF 2进行的表面化.
主要成果:
- 实现了 268 mAh/g 的可逆容量.
- 经过100个循环后,显示出大约99%的优异容量保留.
- STEM-EELS和HAXPES证实了更深的信号和离子/共价协调,表明F-占据了接近表面的氧气空缺点.
结论:
- 引入缺氧和表面化的结合方法有效地抑制了表面退化.
- 离子占用氧气空缺位置,为增强丰富的正极材料提供了一种新的策略.
- 这种方法为开发先进的离子电池提供了一个有前途的途径.
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