高密度锂离子电池正极材料LiNi_(0.8)Co_(0.2)O_2合成的研究

Synthesis of high density LiNi_(0.8)Co_(0.2)O_2

以二次干燥化学共沉淀法制得高密度前驱体Ni0.8Co0.2(OH)2,再与LiNO3混合经两个恒温阶段烧结(600℃恒温6h、800℃恒温24h)得到高密度LiNi0.8Co0.2O2。探讨了锂源、镍源、合成温度、合成时间等因素对产品的影响,从而优化了LiNi0.8Co0.2O2的合成工艺。所得非球形LiNi0.8Co0.2O2粉末振实密度高达3.24g/cm3,大幅度地提高正极材料的体积比能量。X射线衍射分析表明合成的LiNi0.8Co0.2O2具有规整的层状NaFeO2结构,预示着材料具有良好的电化学性能。

Precursor-Ni0.8Co0.2 （OH）2 with high tapping density was prepared by second stage drying method. High density LiNi0.8Co0.2O2 powders was synthesized by sintering the Ni0.8Co0.2（OH）2 and LiNOs at 600℃ for 6h and 800℃ for 24h. The influences of preparation conditions such as raw materials, the mole ratio of Li/（Ni ＋Co）,the sintering temperature and the reaction time of the product were discussed. The synthetic technology was optimized. The tap density of the prepared non-spherical LiNi0.8Co0.2O2 powder reaches 3.24g/cm^3 and high tapping density leads to high volumetric specific capacity. XRD results show the material LiNi0.8 Co0.2O2 with order NaFeO2 layer structure. It promises the material has good electrochemical performance.