Investigation of Lithium difluoro(sulfato)borate as a salt of electrolyte for high-temperature lithium-ion batteries

摘要

Lthium difluoro(sulfato)borate (OBF_2SO_4) is a prospecting salt for electrolyte of lithium-ion batteries. The effect of LiBF_2SO_4 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, LiBF_2SO_4-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 LiCoO_2 half cells at 60 °C, the electrolyte containing the novel salt exerts several advantages, such as stable cycling performance, and good capacity retention performance.