微反应器-共沉淀法制备LiCoPO_4/C及其电化学性能

Preparation and electrochemical property of LiCoPO_4/C by micro-reactor and co-precipitation method

采用微反应器-共沉淀法制备锂离子电池正极材料LiCoPO_4,并对LiCoPO_4进行碳包覆改性研究,分别用X线衍射(XRD)、电感耦合等离子体(ICP)、场发射电子显微镜(FESEM)、透射电子显微镜(TEM)和电化学测试系统对样品进行表征。结果表明:制得的LiCoPO_4颗粒尺寸在200 nm左右,在650℃煅烧温度下,首次放电比容量最佳。经过碳包覆改性之后,颗粒表面包覆了一层碳层,首次放电比容量和循环性能均得到明显提升,在650℃煅烧温度下制备的LiCoPO_4/C复合材料,首次放电比容量达到130 m A·h/g,经过20次循环后还剩70 m A·h/g左右。

LiCoPO4,as cathode material,was prepared by micro-reactor and co-precipitation method, and its property was further explored by carbon coating.The prepared samples were characterized by X ray diffraction （ XRD）,inductively coupled plasma （ ICP ） ,field emission scanning electron microscopy （FESEM）,transmission electron microscopy （ TEM ） and electrochemical tests. Results showed that the average particle size of prepared LiCoPO4 was about 200 nm and the best first discharge capacity was obtained for the sample calcined at 650 ℃. After carbon coating, a uniform layer of carbon was observed on the particles, and the first discharge capacity and cycle performance surface of were promoted obviously.The first discharge capacity of LiCoPO4/C composite calcined at 650 ℃ reached 130 mA ·h/g and the capacity remained at 70 mA · h/g after 20 cycles.