The Synthesis of LiMn(x)Fe(1−x)PO(4)/C Cathode Material through Solvothermal Jointed with Solid-State Reaction

LiMn(x)Fe(1−x)PO(4)/C material has been synthesized through a facile solid-state reaction under the condition of carbon coating, using solvothermal-prepared LiMnPO(4) and LiFePO(4) as precursors and sucrose as a carbon resource. XRD and element distribution analysis reveal completed solid-state reaction of precursors. LiMn(x)Fe(1−x)PO(4)/C composites inherit the morphology of precursors after heat treatment without obvious agglomeration and size increase. LiMn(x)Fe(1−x)PO(4) solid solution forms at low temperature around 350 °C, and Mn(2+)/Fe(2+) diffuse completely within 1 h at 650 °C. The LiMn(x)Fe(1−x)PO(4)/C (x < 0.8) composite exhibits a high-discharge capacity of over 120 mAh·g(−1) (500 Wh·kg(−1)) at low C-rates. This paves a way to synthesize the crystal-optimized LiMn(x)Fe(1−x)PO(4)/C materials for high performance Li-ion batteries.