Abstract:Li and Fe atom sites of LiFePO4 were doped by rare earth ions (Er3+, Y3+, Nd3+), respectively. The change of structure and performance of LiFePO4 was investigated by XRD, galvanostatic charge and discharge experiments and electrochemical impedance tests. The results show that the microstructure and performance of doped samples are interrelated with radii of doping ions and doping site. LiFe0.99Y0.01PO4 displays the excellent electrochemical performance. Its initial discharge capacity is 149.8 mAh·g-1 under the current density of 15 mA·g-1. When 300 mA·g-1 current is applied, its discharge capacity is 134.3 mAh·g-1. Its capacity retention is 99.1% after 50 cycles.