锆、钛复合掺杂锂钴氧化物正极材料制备及电化学性能研究

Studies on the preparation and the electrochemical properties of LiCoO_2 doping Zr and Ti positive plate material

以碳酸锂、氧化钴为主要原料,掺入化学计量的超细二氧化锆、超细二氧化钛,按球料比3∶1,在转速500r/min经1h行星式球磨后,经900℃固相烧结制备了锂离子电池正极材料LiCo0.9Zr0.03Ti0.07O2,用X射线衍射(XRD)、扫描电镜(SEM)对材料的结构与形貌进行了研究,结果表明LiCo0.9Zr0.03Ti0.07O2与LiCoO2一样具有六方层状结构。在0.2C倍率下材料的初始放电容量达147mAh/g,2C倍率下初始放电容量达140.5mAh/g,3.6V放电平台比例达89.6%,500次循环后容量衰减7.5%,材料大电流放电性能好、循环寿命长。

A LiCo0.9 Zr0.03 Ti0.07 O2 positive plate material of lithium ion battery was prepared by high temperature solid sintering at 900℃ whose preeursor was obtained using Li2CO3, Co3O4, and doping substance uhrofine ZrO2, ultrofine TiO2 by planetary grinding for 1h, at 500 rotations per minute and the ball to material weight ratio （BMR） at 3 ： 1. The mierographs and structure of this material were characterized by SEM, XRD. The results indicate LiCo0.9 Zr0.01 Ti0.07 0O2 has hexagonal lamellar structure. The first cycle capacity of prepared material were 147mAh/g at 0. 2C rate, and 140. 5mAh/g at 2C. And also the prepared material show better cycle performance and higher discharge voltage, the proportion of time above 3.6V in discharge reach to 89.6%, the capacity retention were 92.5% after 500 cycles.