采用多元醇法合成了高电位LiCoPO4正极材料. 以甲苯为碳源，在LiCoPO4表面化学气相沉积包覆一层厚度约3 nm的导电碳层. 通过XRD、SEM、TEM、CV以及恒流充放电曲线等方法分析、观察和测试样品的晶体结构、微观形貌以及电化学性能. 结果表明，多元醇法合成的样品为纯相LiCoPO4，碳包覆LiCoPO4/C电极0.1C倍率首次放电容量达到132 mAh·g-1，50周期循环容量保持78%. 循环伏安和微分容量曲线表明LiCoPO4/C电极的充放电过程Li+脱出和嵌入均为两步步骤.
High potential LiCoPO4 cathode material was synthesized by polyol method. Carbon layer of ca. 3 nm thick was coated on the LiCoPO4 surfaces by chemical vapor deposition from methylbenzene. Crystalline structure, morphology and electrochemical performance of the sample were studied by XRD, SEM, TEM, CV and galvanostatic charge/discharge curve. The synthesized material via polyol method showed a pure phase of LiCoPO4. The LiCoPO4/C electrode delivered a high discharge capacity of 132 mAh·g-1 and maintained 78% of the initial capacity after 50 cycles at 0.1C rate. The two-step extraction/insertion behavior of Li+ in LiCoPO4/C was observed from cyclic voltammogram and differential capacitance curves.
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