Abstract: LiNi_0.8Co_0.2O₂ cathode material for lithium-ion batteries was prepared from sol-gel method using nitrates and starch as the starting materials. The synthesized material was characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM) and galvanostatic charge/discharge cycling. The XRD data of the product show that the synthesized material are single phases and all the peaks are indexable to the layered α-NaFeO₂ structure. The synthesized LiNi_0.8Co_0.2O₂ presents a narrow distribution of small particles and exhibits a good electrochemical property with initial discharge specific capacity of 183.1 mAh/g and the discharge specific capacity of 171.3 mAh/g after 50 cycles in the voltage range 2.75~4.50 V (versus Li+/Li) at a constant current density of 0.2 mA/cm2.

Key words:

摘要： 以硝酸盐和淀粉为原料，采用溶胶-凝胶方法合成LiNi_0.8Co_0.2O₂锂离子电池正极材料，利用X射线衍射（XRD）、扫描电镜(SEM)和电化学测试等方法对合成材料的结构、形貌以及电化学性能进行表征。结果表明，合成材料为单一晶相的α-NaFeO₂型层状结构，颗粒小且分布均匀，在电压为2.75~4.50 V (vs. Li+/Li) 范围内，以0.2 mA/cm2电流密度下经恒电流充放电测试，其首次放电比容量为183.1 mAh/g，经过50周充放电循环后放电比容量为171.3 mAh/g，表现出较大的初始放电比容量和良好的循环性能。

关键词: 锂离子电池 , 正极材料 , 溶胶－凝胶方法