盐缩电解质构建高弹性模块 丰富多层氧化物阴极的介相
Zhijie Han1,2, Yuan Liang1,2, Shu Zhao1,2
1Institute of Advanced Battery Materials and Devices, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, P.R. China.
ACS applied materials & interfaces
|November 13, 2024
概括
在溶剂中使用六酸 (LiPF) 的新型缩电解质稳定了高压丰富的多层氧化物 (LLO) 电池. 这种方法提高了性能,并减少了先进能源存储的容量衰减.
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:
- 使用富含的层氧化物 (LLOs) 的离子电池 (LIB) 提供高能量密度,但面临挑战.
- 由于电解质的不稳定性,LLOs在高工作电压 (高达4.8V) 时表现出快速的容量和电压衰减.
- 开发稳定的电解质对于释放下一代电池中LLOs的全部潜力至关重要.
研究的目的:
- 开发一种稳定的电解质,用于基于高压LLO的LIB.
- 研究缩电解质对电化学性能和稳定性的影响.
- 为了减轻LLO阴极的容量和电压衰减.
主要方法:
- 在乙烯碳酸盐 (FEC) 和二甲基碳酸盐 (DMC) 溶剂中制备4M六酸 (LiPF6) 盐缩电解质.
- 分析溶剂结构和+溶解在缩与稀释电解质中的分析.
- 使用开发的电解质对LLO阴极进行电化学测试,包括循环性能和电压稳定性测量.
主要成果:
- 4M LiPF6 电解质表现出一种经过修改的溶剂结构,具有增加的 DMC 溶解和自由 FEC,扩大了工作电压窗口.
- 在LLO表面形成一个薄而弹性,富含LiF的介相,抑制侧面反应和过渡金属溶解.
- 电化学性能显著提高,仅显示0.46mV/循环电压衰变,并在500个循环后保持80.3%的容量.
结论:
- 盐度电解质提供了一种简单而有效的策略,以提高LLO阴极的稳定性.
- 形成的富含LiF的介相在防止降解途径方面发挥着至关重要的作用.
- 这种方法为开发基于LLO材料的高能量密度LIB铺平了道路.
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