用离子剂调节溶解层,使4.6V超稳定的商用LiCoO2成为可能
Haoyu Kang1, Xuefeng Zhang2, Yiming Ma2
1State Key Laboratory of Advanced Electromagnetic Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
Chemistry (Weinheim an der Bergstrasse, Germany)
|October 17, 2024
概括
研究人员改进了高压氧化电池,使用trifluorophenyl) (TPFPB) 来创建稳定的接口. 这提高了下一代离子电池的循环稳定性.
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:
- 离子电池 (LIB) 的高能量密度需要将氧化 (LCO) 的切断电压提高到4.6V以上.
- 由于不可逆转的相位过渡,结构性降解,特别是在表面晶格上,是高压LCO的一个主要挑战.
- 电极-电解质接口 (EEI) 在保持LCO的结构稳定性方面发挥着至关重要的作用.
研究的目的:
- 为了研究三{pentafluorophenyl) (TPFPB) 作为阴离子化剂的机制.
- 了解TPFPB如何调节LCO电极上的阴极电解质介相 (CEI) 层.
- 提高LIBs中高压LCO的结构稳定性和循环性能.
主要方法:
- 探讨TPFPB作为阴离子合剂的操作机制.
- 在使用TPFPB添加剂的LCO电极上CEI层的调节.
- 在EC/EMC中含有1mol L-1 LiPF6的电解质配方,包含TPFPB.
主要成果:
- 由于高HOMO能量水平和TPFPB-PF6−的优先分解,构建了一个强大的,富含LiF的CEI层.
- 富含LiF的CEI层显著提高了电极/电解质接口的稳定性.
- 在高压条件下,Li/LCO半电池和4 Ah Gr/LCO袋式电池表现出增强的循环稳定性.
结论:
- TPFPB有效调节CEI层,提高高压LCO电极的稳定性.
- 开发的电解质添加剂为提高经济高压LIB的性能提供了一个有希望的策略.
- 这项研究为开发先进,高能量密度的LIBs开辟了新的途径.
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