煅烧温度对523型镍钴锰酸锂正极材料电化学性能的影响

Effects of Calcination Temperature on Electrochemical Properties of 523-Type Lithium Nickel-Cobalt-Manganese Oxide as Positive Electrode Materials

摘要: 研究了煅烧温度对镍钴锰酸锂的物相和电化学性能的影响。利用液相共沉淀法 + 固相煅烧工艺制备了目标产物，并综合利用XRD、恒电流充放电技术及交流阻抗技术对材料物相和电化学性能进行了表征。结果表明，900℃下煅烧获得的产物层状结构发育完全，结晶度高，离子混排度低，首次放电比容量达到166.3 mAh∙g−1，2C下放电比容量为73.2 mAh∙g−1。900℃产物的电荷转移阻抗较小，提高了锂离子的扩散速度，有利于倍率充放电性能的改善。

Abstract: The effect of calcination temperature on the phase and electrochemical properties of lithium nickel-cobalt-manganese oxide was studied. The target product was prepared by liquid phase co-precipitation and solid phase calcination, and the phase and electrochemical properties of the material were characterized by XRD, constant current charge-discharge technique and AC imped-ance technique. The results show that the product obtained by calcination at 900˚C has a well-developed layered structure, high crystallinity and low ionic mixing. The initial discharge capacity is up to 166.3 mAh∙g−1. The charge transfer impedance of the product is small, which im-proves the diffusion rate of lithium ion and improves charge/discharge rate.