(中南大学 冶金与环境学院，长沙 410083)
摘 要: 以碳酸氢铵为沉淀剂采用共沉淀法合成球形Co0.9Ni0.05Mn0.05CO3前驱体，以碳酸盐前驱体和Li2CO3为原料，在空气中通过固相反应制备出LiCo0.9Ni0.05Mn0.05O2正极材料，研究烧结温度对产物结构及电化学性能的影响。采用扫描电镜(SEM)、X射线衍射(XRD)和光电子能谱(XRS)分别表征样品的形貌、结构和元素价态。结果表明：不同烧结温度下合成产物的性能差别很大，较适合的合成温度为900 ℃；在3.0~4.5 V电压范围内，LiCo0.9Ni0.05Mn0.05O2显示出较好的倍率性能；在25 ℃测试条件下，材料在0.2C、0.5C、1C、5C和10C时的放电比容量分别为181.6、178.3、173.9、167.8和157.1 mA？h/g。
关键字: 锂离子电池；正极材料；碳酸氢铵；共沉淀
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:The spherical precursor of metal carbonate, Co0.9Ni0.05Mn0.05CO3, was prepared by co-precipitation method using NH4HCO3 as precipitating agent. LiCo0.9Ni0.05Mn0.05O2 was prepared by solid-state reaction method in air using Co0.9Ni0.05Mn0.05CO3 and Li2CO3 as starting materials. The effects of sintering temperature on the structure and electrochemical properties of the product were studied. The morphology and structure of LiCo0.9Ni0.05Mn0.05O2 were characterized by SEM and XRD, respectively. The valence state of transition metal was determined by XPS. The results show that sintering temperature has a critical role in the performance of the product and the suitable sintering temperature is 900 ℃. LiCo0.9Ni0.05Mn0.05O2 exhibits good cycle performance and high rate capability within the voltage range of 3.0-4.5 V. At 25 ℃, the initial discharge capacity are 181.6, 178.3, 173.9, 167.8 and 157.1 mA？h/g at 0.2C, 0.5C, 1C, 5C and 10C, respectively.
Key words: lithium-ion battery; cathode material; ammonium bicarbonate; co-precipitation
