AlPO4-coated LiVOPO4 were prepared by sol-gel method using LiVOPO4, Al(NO3 )3 · 9H2O and H3PO4 as raw materials. The microstructure, surface morphology and electrochemical properties were characterized by various electrochemical methods in combination with thermogravimertric(TG) analysis and differential thermal analysis(DTA), X-ray diffraction(XRD) and scanning electron microscope(SEM). It is found that the amorphous AlPO4 layer coats on the surface of LiVOPO4. The AlPO4-coated LiVOPO4 cathode material has increased reversible capacity, stabilized cycling performance and improved rate performance, which are attributed to the minimization harmful side reactions within the batteries by placing a protective barrier layer between the oxidizing cathode material and liquid electrolyte and the decrease of electrochemical impedance.%以LiVOPO4、Al(NO3)3·9H2O、H3PO4为原料,采用溶胶-凝胶法制备了AlPO4包覆的LiVOPO4粉末(AlPO4包覆LiVOPO4).采用热重与差热分析、X射线衍射分析、扫描电镜分析以及电化学测试等手段对AlPO4包覆LiVOPO4的微观结构、表面形貌和电化学性能进行了研究.结果表明,AlPO4以无定形态包覆于LiVOPO4颗粒表面形成AlPO4包覆LiVOPO4粉末.由于在LiVOPO4颗粒表面包覆了一层无定形的AlPO4后,阻止了电极与电解质溶液之间的副反应,降低了电化学阻抗,因此,与未包覆的LiVOPO4粉末相比,AlPO4包覆LiVOPO4具有更高的可逆容量、更稳定的循环性能和更好的倍率性能.
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