Preparation of LiMn0.4Fe0.6PO4/C Composite by A New Route Combining Solid-state Reaction with Hydrothermal Synthesis

The olivine type LiMn0.4Fe0.6PO4 was synthesized via a new route that combining solid-state reaction with hydrothermal synthesis from Li2CO3, FeC2O4 center dot 2H(2)O, MnCO3 and NH4H2PO4 (at molar ratio of 5:6:4:10). The structure, particle size and surface morphology of these cathode active Materials were investigated by XRD, SEM and TEM techniques. The electrochemical properties of LiMn0.4Fe0.6PO4/C as cathode in lithium-ion cells were tested via cyclic voltammetry and galvanostatic charge-discharge measurements. Phase-pure particles of size similar to 120 nm are prepared with a conductive, thin web of carbon surrounding them. Cyclic voltammetry shows the active voltage range of the material which consists of two pairs of redox peaks: 3.5 V corresponding to Fe3+/Fe2+ reaction and 4.0 V corresponding to Mn3+/Mn2+ reaction. An initial discharge capacity of 160 mAh/g at 0.1C, 143 mAh/g and a stable cycling property at 0.5C are obtained for the LiMn0.4Fe0.6PO4/C composite.