Electrolyte solution for the improved cycling performance of LiCoPO4/C composite cathodes

The markedly enhanced cycling performance of a LiCoPO4/C cathode was observed in a 1 M LiPF6 in fluoroethylene carbonate (FEC)/dimethyl carbonate (DMC) electrolyte solution compared to 1 M LiPF6 in ethylene carbonate (EC)/DMC electrolyte solution. Further improvement was achieved by the addition of 0.5–1% of trimethylboroxine (TMB) additive to the electrolyte solution. The capacity retention of the LiCoPO4 electrode in this electrolyte is 90% with a faradaic efficiency of 98% after 100 cycles.

► Enhanced cycling performance of LiCoPO4 cathodes in FEC-based electrolyte ► Enhanced cycling performance of LiCoPO4 cathodes with trimethylboroxine additive ► Decrease of the electrolyte volume:LiCoPO4 mass ratio improves cycling of the cells.