Journal Article

Thermal runaway of Lithium-ion batteries employing LiN(SO2F)2-based concentrated electrolytes

Li, Yalun, Han, Xuebing, Wang, Li, Ootani, Issei, Ren, Dongsheng, Ren, Weining, Hou, Junxian, Lu, Languang, Ouyang, Minggao, Nitta, Yoshiaki, Feng, Xuning, He, Xiangming, Ohma, Atsushi, Li, Yan

2020

Overview

Concentrated electrolytes usually demonstrate good electrochemical performance and thermal stability, and are also supposed to be promising when it comes to improving the safety of lithium-ion batteries due to their low flammability. Here, we show that LiN(SO 2 F) 2 -based concentrated electrolytes are incapable of solving the safety issues of lithium-ion batteries. To illustrate, a mechanism based on battery material and characterizations reveals that the tremendous heat in lithium-ion batteries is released due to the reaction between the lithiated graphite and LiN(SO 2 F) 2 triggered thermal runaway of batteries, even if the concentrated electrolyte is non-flammable or low-flammable. Generally, the flammability of an electrolyte represents its behaviors when oxidized by oxygen, while it is the electrolyte reduction that triggers the chain of exothermic reactions in a battery. Thus, this study lights the way to a deeper understanding of the thermal runaway mechanism in batteries as well as the design philosophy of electrolytes for safer lithium-ion batteries. Concentrated electrolytes display superior thermal stability due to their non-flammability nature. Here, the authors show that LiN(SO 2 F) 2 -based concentrated electrolytes are incapable of solving the safety issues due to heat release during reaction between the lithiated graphite and electrolyte.

• Publisher: Nature Publishing Group UK,Nature Portfolio
• Subject: 140/146 / 140/58 / 639/301/299/891 / 639/4077/4079/891 / 639/638/899 / Humanities and Social Sciences / multidisciplinary / Science / Science (multidisciplinary)