Investigation of Lithium Difluoro (Sulfato) Borate as a Salt of Electrolyte for High-Temperature Lithium-Ion Batteries

Abstract

Lthium difluoro (sulfato) borate (LiBF2SO4) is a prospecting salt for electrolyte of lithium-ion batteries. The effect of LiBF2SO4 salt on conductivity, charge-discharge capacities, temperature performance, cycling life and storage life at 60 °C is investigated. In graphite half cells at 60 °C, LiBF2SO4-ethylene carbonate (EC)/ dimethyl carbonate (DMC) electrolyte favourably facilitates the formation of a thermal stable, effective and conductive interface film on the surface of carbonaceous anode. Besides, in LiCoO2 half cells at 60 °C, the electrolyte containing the novel salt exerts several advantages, such as stable cycling performance, and good capacity retention performance.