Compatibility of lithium difluoro(sulfato)borate-based electrolyte for LiMn2O4 cathode

Abstract

Lithium difluoro(sulfato)borate (LiBF2SO4) is investigated as a lithium salt for non-aqueous electrolytes for LiMn2O4 cathode in lithium-ion batteries. Inductively coupled plasma-atomic emission spectrometry analysis is used to analyze the Mn dissolution. Scanning electron microscopy and AC impedance measurements analysis are used to analyze the formation of the surface film on the surface of LiMn2O4 cathode. These results demonstrate that LiBF2SO4-based electrolyte favourably facilitates the formation of an effective and conductive interface film on the cathode surface to improve the stabilization of cathode/electrolyte interface. Besides, LiMn2O4 cells using LiBF2SO4-based electrolyte exerts several advantages, such as stable cycling performance, low cell impedance, low polarization resistance, and good rate performance. It suggests that LiBF2SO4-based electrolyte has good compatibility with LiMn2O4 cathode, and LiBF2SO4 would be a very promising lithium salt for LiMn2O4 cathode in lithium-ion batteries.