Effects of doping ionic valencies on electrochemical performance of LiFePO_4

Olivine LiFePO4 is a new kind of cathode material for lithium-ion batteries. Four kinds of metallic ions Ga3+, Ti4+, Ta5+ and Mo6+ were doped in Fe (M2) site in order to investigate the effects of doping ionic valencies on the electrochemical performance of LiFePO4. The results of X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS) and electrochemical performance demonstrate that the doped Ti4+ material has the best electrochemical performance.