Double-salt electrolyte for Li-ion batteries operated at elevated temperatures

被引：38

作者：

Chen, Long ^{[1
]}

Lu, Jianhao ^{[1
]}

Wang, Yibo ^{[1
]}

He, Pan ^{[1
]}

Huang, Shaobo ^{[2
]}

Liu, Yan ^{[2
]}

Wu, Yanzhou ^{[3
]}

Cao, Gaoping ^{[1
]}

Wang, Li ^{[3
]}

He, Xiangming ^{[3
]}

Qiu, Jingyi ^{[1
]}

Zhang, Hao ^{[1
]}

机构：

[1] Res Inst Chem Def, Beijing 100191, Peoples R China

[2] Univ Sci & Technol Beijing, Inst Adv Mat & Technol, Beijing 100083, Peoples R China

[3] Tsinghua Univ, Inst Nucl & New Energy Technol, Beijing 100084, Peoples R China

来源：

ENERGY STORAGE MATERIALS | 2022年 / 49卷

基金：

中国国家自然科学基金; 中国博士后科学基金;

关键词：

Liquid electrolytes; High temperature; Fe dissolution; Solid electrolyte interfaces (SEI); Thermal safety; THERMAL RUNAWAY MECHANISM; LITHIUM; GRAPHITE; CARBONATE; LI4TI5O12; CORROSION; BEHAVIOR; POLYMER; STORAGE;

D O I：

10.1016/j.ensm.2022.04.036

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Lithium ion batteries (LIBs) have swept the whole energy storage field. However, the current mainstream lithium batteries are difficult to operate stably at high temperature (> 60?) due to the decomposition of electrolyte and solid electrolyte interphase (SEI), the cathode metal elements dissolution behavior, and potential thermal runaway. Here, We report a double-salt electrolyte with lithium bis(fluorosulfonyl)imide (LiFSI) and lithium difluoro(oxalato)borate (LiDFOB) as electrolyte salt, fluoroethylene carbonate (FEC), and tetra(ethylene glycol) dimethyl ether (TEGDME) as cosolvent, which delivers excellent ionic conductivity, high electrochemical stability and satisfactory ability to impede the dissolution of Fe element under elevated temperature (70?). In addition, the electrolyte is benefited to form a robust and thermal-resistance solid-electrolyte interface (SEI) layer on the surface of graphite (Gr) anode, which shows improved decomposition temperature (86?). The assembled thermally stable and high-safety 1300 mAh 18650-type LiFePO4|Gr cell shows high Coulombic efficiency (~99.7%), improved cycling stability with discharge capacity 871.1 mAh after 200 cycles at 0.5 C and 70?. This work affords a splendid strategy for address the unstable interface at both cathode and anode for safe high-temperature LIBs.

引用

页码：493 / 501

页数：9

共 47 条

[1] Liquid electrolyte based on lithium bis-fluorosulfonyl imide salt: Aluminum corrosion studies and lithium ion battery investigations [J].