Platelet-shape LiFePO4/Fe2P/C composite material as a high-rate positive electrode for Li-ion batteries

In this work we present novel approach to enhance the performance of the LFP electrodes based on simultaneous engineering of phase composition and morphology in the LiFePO4 – Fe2P – carbon system. We show the two step fabrication method of composite materials made of carbon coated nanometric platelet LiFePO4 and metallic Fe2P species, the synthesis involve co-precipitation of platelet LFP particles with subsequent high temperature annealing under reductive conditions. We successfully prepare LFP/Fe2P/C composites comprising 8 wt% Fe2P with enhanced electrochemical properties. The material at high current rates – 10 C delivers discharge specific capacity close to 110 mAh gLFP−1. The cell with investigated LFP electrodes working in the 2.5–4.5 voltage regime exhibits high stability and its discharge specific capacity fading only 3% after 60 cycles and remains equal to 159 mAh gLFP−1.