Lithium Bis(fluorosulfonyl)imide, LiFSI

CAS Number: 171611-11-3

Lithium Bis(fluorosulfonyl)imide (often simply referred as LiFSI), formula LiF2NO4S2, appears to be white powder, with its molecular weight 187.07, melting point 124-128°C (255-262.4°F). It is thermally stable up to 200 °C. It has good electrochemical stability and high conductivity. It exhibits far superior stability towards hydrolysis, better low temperature performance and more environmentally friendly than LiPF6.


LiFSI is a promising new electrolyte additive for power lithium ion batteries showing increased conductivity over LiPF6. Bis(fluorosulfonyl)imide has also been tested in next generation gel polymer electrolytes, as well as primary lithium battery electrolyte, with improved safety properties. It can be used as a polymerization catalyst and also as an antistatic agent in the industrial field.

Data Sheet
Lithium Bis(fluorosulfonyl)imide, LiFSI