锂离子电池正极材料掺杂LiFePO₄的报道已很多，而涉及掺杂LiFePO₄的表面成份及结构的研究仍很少见. 本文采用溶剂热法一步得了表面富Al的LiFePO₄正极材料. TEM测试证实LiFePO₄的表面形成均匀的无定型包覆层；俄歇电子能谱和软X射线吸收谱共同揭示了其表面的自包覆层为部分Al替代Fe的LiFe_1-xAl_xPO₄. 表面富Al（x=0.02）的LiFePO₄显示了较好的电化学倍率性能和低温性能，充放电-10 ^oC的条件下，电压范围2.2 ~ 4.2 V、0.1C倍率电极的放电比容量为98 mAh·g^-1，0.5C倍率放电比容量可达70 mAh·g^-1. 这归因于Al的加入改变了材料体相及表面的电子结构，增加了体相电子的传导及表面离子的传导.

Despite there are many successful reports about the preparation of electrode materials with surface coating for lithium ion batteries, the study in surface self-coating of cathode materials using segregation of doping elements and their electrochemical properties is still very rare. The LiFePO₄ particles with rich-Al on the surface were synthesized by one step solvothermal route. TEM results demonstrated that the surface of the obtained LiFePO₄ particles was well-covered by the amorphous coating. The soft X-ray absorption spectroscopy (XAS) and Auger electron spectroscopy (AES) component analyses revealed that the amorphous coating was composed of LiFe_1-xAl_xPO₄ by part of Al substitution to Fe. The LiFePO₄ material with surface rich-Al showed good electrochemical rate capacity and low temperature performance. This could be attributed to the changes of the bulk and surface electron structures which promote the bulk electron and surface ionic conductivities.