电解质调节用于稳定4.8V高压离子电池的无层正极接口
Mingyuan Ma1, Zhenglu Zhu1, Dan Yang1
1Institute of New Energy Vehicles, School of Materials Science and Engineering, Tongji University, Shanghai 201804, P. R. China.
ACS applied materials & interfaces
|February 29, 2024
概括
这项研究通过将乙烯碳酸盐 (FEC) 和LiPO2F2添加到电解质中来增强无的离子电池阴极. 这会产生一种保护性接口膜,提高高压性能和稳定性,用于先进的能量存储.
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:
- 没有的分层氧化物阴极 (LiNi0.65Mn0.35O2) 为离子电池 (LIB) 提供高能量密度.
- 高压操作导致有害的副作用和结构退化,限制了实际应用.
- 有效的界面稳定对于高性能LIBs至关重要.
研究的目的:
- 开发一种电解质添加剂策略,以提高无LIB阴极的界面稳定性和高压性能.
- 用特定的添加剂研究阴极电解质接口 (CEI) 薄膜的形成和特性.
- 评估CEI薄膜对Li的循环稳定性和容量保留Li的电池的影响.
主要方法:
- 通过加入乙烯碳酸盐 (FEC) 和LiPO2F2添加剂进行电解质修饰.
- 阴极电解质接口 (CEI) 膜组成和结构的表征.
- 在高电压条件下 (切断值为4.8V) 对Li的电池进行电化学测试.
主要成果:
- 在阴极表面形成一个均,密集的有机-无机混合CEI膜 (C-F,LiF,Li2CO3,LiPO2F2物种).
- CEI膜有效地抑制了接口反应和结构损伤.
- 提高了高压循环性能:在4.8V的150个循环中81.3%的容量保留,而没有添加剂的76.1%.
结论:
- FEC和LiPO2F2添加剂的协同作用显著提高了无正极的界面稳定性.
- 开发的电解质策略为设计具有更好的性能和寿命的高压LIB提供了可行的途径.
- 这项研究为推进下一代能源存储设备的无正极材料提供了有前途的解决方案.
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