Enhanced electrochemical properties of LiMn1-xFexPO4/C composite cathode materials prepared by sol–gel method

Abstract Olivine-type LiMn 1- x Fe x PO 4 /C( x =0, 0.1, 0.3 and 0.5) composite materials were synthesized by the sol–gel method employing N , N -dimethylformamide (DMF) as a dispersing agent, and the structure and morphology of the as-prepared nanoparticles were characterized. For Fe 2+ doping contents of x =0, 0.1, 0.3, and 0.5, initial specific discharge capacities of 96.8, 137.6, 152.3, and 161.5 mA h g −1 at 0.05 C were obtained, respectively. The LiMn 0.5 Fe 0.5 PO 4 /C composite in particular exhibited an excellent reversible capacity of 132 mA h g −1 at a charge–discharge rate of 1 C. Finally, LiMn 0.5 Fe 0.5 PO 4 /C retained 155.5 mA h g −1 (96.3%) of the initial specific discharge capacity after 50 cycles, demonstrating excellent cyclability.