Enhanced electrochemical properties of LiFePO4 cathode material by CuO and carbon co-coating

CuO and carbon co-coated LiFePO4 composites were prepared by a chemical precipitation method. The incomplete carbon network is repaired by the nano-sized CuO as proved by high-resolution transmission electron microscopy. The effects of the co-coating of CuO and carbon on the cycle performance of LiFePO4 cathode are investigated. It is found that the co-coating reduces the capacity fading especially at high charge/discharge rates. Results of the impedance spectroscopy and cyclic voltammogram measurements indicate that the interfacial resistances decrease remarkably and the polarization of the cathode is reduced significantly. This can be mainly attributed to the improvement of electrochemical kinetics by the co-coating with nano-sized CuO and carbon.