Manganese Doped LiFePO4 as a Cathode for High Energy Density Lithium Batteries

Abstract: Porous LiMn0.6Fe0.4PO4 (LMFP) was synthesized by a sol-gel process. Uniform dis-persion of the conductive carbon source throughout LMFP with uniform carbon coating was achieved by heating a stoichiometric mixture of raw materials at 600oC for 10 h. The crystal structure of LMFP was investigated by Rietveld refinement. The surface structure and pore properties were investigated by SEM, TEM and BET. The LMFP so obtained has a high spe-cific surface area with a uniform, porous, and web-like nano-sized carbon layer at the surface. The initial discharge capacity and energy density were 152 mAh/g and 570 Wh/kg, respectively, at 0.1 C current density, and showed stable cycle performance. The combined effect of high porosity and uniform carbon coating leads to fast lithium ion diffusion and enhanced electro