中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 16 No. 1 February 2006 |
of cathode material Co-coated LiNiO2 for Li-ion batteries
（1. Laboratory on Solid State Ionics, University of Science and Technology Beijing, Beijing 100083, China;
2. Faculty of Materials and Technology Engineering, Jiangxi University of Science and Technology,
Ganzhou 341000, China）
Abstract:Spherical Ni(OH)2 powder coated with Co(OH)2 as raw material was mixed with LiOH to synthesize cathode material for lithium ion battery by using solid-state reaction. After sintered at temperature above 600 ℃, a solid solution with layer structure was formed. The result of XPS shows that it is a concentration gradient material with higher cobalt content at the surface, and the gradient decreases with increasing sintering temperature from 650 to 750 ℃. This new gradient material, called as Co-coated LiNiO2, exhibits excellent electrochemical performances for the cathode of Li-ion batteries in comparison with LiNiO2 and Co-doping LiNiO2. The discharge capacity of Co-coated LiNiO2 is over 180 mA•h/g and capacity decay per cycle is less than 0.07% when Co-coated LiNiO2 consisting of 92% nickel and 8% cobalt was sintered at the temperatures between 650－670 ℃. Though initial discharge capacity could be increased with higher sintering temperature, the cycle life would be reduced.
Key words: Li-ion battery; LiNiO2; LiCoO2; Ni(OH)2; Co(OH)2; cathode material; gradient cathode material; electrochemical performance
