A Low-Concentration Electrolyte for High-Voltage Lithium-Metal Batteries: Fluorinated Solvation Shell and Low Salt Concentration Effect

被引：74

作者：

Deng, Rongyu ^{[1
]}

Chu, Fulu ^{[1
]}

Kwofie, Felix ^{[1
]}

Guan, Zengqiang ^{[1
]}

Chen, Jieshuangyang ^{[1
]}

Wu, Feixiang ^{[1
]}

机构：

[1] Cent South Univ, Sch Met & Environm, Hunan Prov Key Lab Nonferrous Value Added Met, Engn Res Ctr,Minist Educ Adv Battery Mat, Changsha 410083, Peoples R China

来源：

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION | 2022年 / 61卷 / 12期

基金：

中国国家自然科学基金;

关键词：

Cathode; Fluoroethylene Carbonate; LiF-Rich SEI; Lithium-Metal Batteries; Low-Concentration Electrolyte; FLUOROETHYLENE CARBONATE; PERFORMANCE; ANODE; SEI;

D O I：

10.1002/anie.202215866

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Concentration of electrolyte has significant effects on performances of rechargeable batteries. Previous studies mainly focused on concentrated electrolytes. So far, only several recipes on low-concentration electrolytes were studied, performing enhanced performance in advanced rechargeable batteries. Here, based on common electrolyte components, a low-concentration electrolyte composed of 0.2 M lithium hexafluorophosphate (LiPF6) solvated in fluoroethylene carbonate (FEC) and ethyl methyl carbonate (EMC) is employed for high-voltage Li metal battery. The synergistic working mechanisms of introducing fluorine-containing solvent in the solvated structure and low salt concentration effect are revealed, resulting in LiF-rich, uniform, and robust solid electrolyte interphase layer and fewer unfavorable decomposition products. As a result, this low-concentration electrolyte significantly enhances electrochemical performances of Li||Li symmetric cells and high-voltage LiCoO2||Li batteries.

引用

页数：10

共 39 条

[1] High Energy Density Rechargeable Batteries Based on Li Metal Anodes. The Role of Unique Surface Chemistry Developed in Solutions Containing Fluorinated Organic Co-solvents [J].