Effect of vinyl ethylene carbonate on the compatibility between graphite and the flame-retarded electrolytes containing dimethyl methyl phosphonate

Effect of the content of vinyl ethylene carbonate (VEC) on the compatibility between the graphite anode and the electrolytes containing 10–30% dimethyl methyl phosphonate (DMMP) was investigated by cyclic voltammetry measurement. Impact of the contents of VEC and DMMP on the formation of the solid electrolyte interface layer was discussed, and a competitive mechanism between the destructive effect of DMMP decomposition and the positive effect of VEC was proposed. In the LiCoO₂/graphite cells, the electrolytes modified by DMMP and VEC exhibited satisfying cell performances, especially for the electrolyte with 10% DMMP and 2% VEC.