Abstract:Mg-doped and the rheological phase method are applied to improve the electrochemical performances of LiFePO₄. The effect of different doping content and different preparation method on the properties of LiFePO₄ are studied. The effect of temperature and content of Mg doping on the structure and chemical performance of LiFePO₄ are researched. The results of SEM,XRD and electrochemical performances indicate that Mg doping can improve the electrochemical performance obviously,the discharge capacity of LiFe_1-xMg_xPO₄ with 5% Mg doping is 140.7 mAh/g in 0.1 C. The electrochemical performance can improve more if the LiFe_1-xMg_xPO₄ material is prepared by rheological phase method,with the discharge capacity reaching 147.5 mAh/g at 0.1 C.