WO2 modified LiFePO4/C cathode materials with improved electrochemical performance synthesized by in-situ synthesis method

WO2 modified LiFePO4/C cathode materials were prepared by a in-situ synthesis method. The structures and compositions of samples were analyzed by XRD, SEM, TEM and EDS. The electrochemical performances of samples were analyzed with charge-discharge test, electrochemical impedance spectroscopy and cyclic voltammetry. WO2 can sufficiently coat on the particles surface of LiFePO4 and does not alter LiFePO4 crystal structure, the WO2 modified LiFePO4/C samples show improved specific capability and decreased charge transfer resistance. Among the investigated samples, the one with 5 wt% WO2 exhibits the best electrochemical performance. This can be mainly attributed to the improvement of electrochemical kinetics by WO2 adding. (C) 2014 Elsevier B.V. All rights reserved.