A kind of preparation method of bistrifluoromethanesulfonylimide lithium salt

Abstract

The invention discloses a preparation method of LiN(CF3SO2)2 salt. The preparation method comprises the following steps: benzene methanamine is dissolved in an organic solvent and subjected to a sulfonamide reaction with trifluoromethyl sulfonyl chloride or trifluoromethyl sulfonyl fluoride, benzyl bis(trifluoromethyl sulfamide) is obtained and reduced, and bis(trifluoromethyl sulfamide) is obtained; the obtained bis(trifluoromethyl sulfamide) and resin lithium are subjected to ion exchange in an anhydrous solvent, and a final product LiN(CF3SO2)2 salt is obtained. According to the method, raw materials are low in price and easy to obtain, reaction procedures are simple, the yield is high, nearly no pollution is caused, rigid and dangerous reaction conditions are avoided, the product is easy to purify, and the method is suitable for large-scale production in China.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion battery electrolytes, and in particular relates to a preparation method of bistrifluoromethanesulfonylimide lithium salt. Background technique [0002] Lithium bistrifluoromethanesulfonyl imide (LiN(CF 3 S0 2 ) 2 , hereinafter referred to as LiTFSI) is an electrolyte substance with wide application prospects. LiTFSI has suitable conductivity, high thermal stability and electrochemical stability; the probability of side reactions is small, and corrosive gases such as HF will not be generated. An indispensable high-tech product in the electrolyte of lithium-ion secondary batteries. With the continuous development of the lithium battery industry, it can also be used as a catalyst and ionic liquid for multiple purposes, and its market demand is bound to increase. [0003] The previous synthetic method of bistrifluoromethanesulfonamide lithium salt mainly uses ammoniacal liquor, ammonium salt o...

AI Technical Summary

Problems solved by technology

[0003] The previous synthetic method of bistrifluoromethanesulfonamide lithium salt mainly uses ammoniacal liquor, ammonium salt or ammonia gas as the source of ammonia, then adds trifluoromethanesulfonyl chloride etc. to synthesize lithium dichlorosulfonylamide, and then carries out fluorine Lithium salt of two trifluoromethanesulfonamide lithium salts obtained in the reaction of lithiation and lithiation, this type of method has the following disadvantages: 1) in the process of industrialized mass production, the accurate amount of ammonia is difficult to finalize, and too much or too little promotes the formation Unnecessary by-products, 2) When ammonia is used in large quantities, it is easy to cause explosions under different temperatures and pressures, making safety issues always a hidden danger

Images