Facile Deposition of the LiFePO4 Cathode by the Electrophoresis Method

Abstract

Lithium iron phosphate (LiFePO4, LFP) is one of the most advanced commercial cathode materials for Li-ion batteries and is widely applied as battery cells for electric vehicles. In this work, a thin and uniform LFP cathode film on a conductive carbon-coated aluminum foil was besieged by the electrophoretic deposition (EPD) technique. Along with the LFP deposition conditions, the impact of two types of binders, poly(vinylidene fluoride) (PVdF) and poly(vinylpyrrolidone) (PVP), on the film quality and electrochemical results has been studied. The results revealed that the LFP_PVP composite cathode had a highly stable electrochemical performance compared with the LFP_PVdF counterpart due to the negligible influence of the PVP on the pore volume and size and retaining high surface area of LFP. The LFP_PVP composite cathode film unveiled a high discharge capacity of 145 mAh g-1 at 0.1C and performed over 100 cycles with capacity retention and Coulombic efficiency of 95 and 99%, respectively. The C-rate capability test also revealed a more stable performance of LFP_PVP compared to LFP_PVdF.