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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.
The high-potential LiCoPO4 cathode material was synthesized by the polyhydric alcohol method. A conductive carbon layer with a thickness of about 3 nm was coated on the surface of LiCoPO4 by using toluene as the carbon source. Through XRD, SEM, TEM and CV, Curve and other methods were used to analyze, observe and test the crystal structure, microstructure and electrochemical properties of the sample.The results showed that the pure LiCoPO4 was synthesized by the polyhydric alcohol method and the initial discharge capacity of 0.1C at carbon-coated LiCoPO4 / C electrode reached 132 mAh · g-1, and the cycle capacity of 50 cycles kept 78%. The cyclic voltammetry and differential capacity curves show that the Li + removal and embedding are both two steps in the charge-discharge process of LiCoPO4 / C electrode.