熔融盐法合成锂离子电池正极材料纳米LiNiO2

Nano-LiNiO_2 as cathode material for lithium ion battery synthesized by molten salt method

采用熔融盐法,在较低的温度和较短的时间制备了符合理论化学计量比的纳米LiNiO2.研究表明,经过空气中的低温预烧,可以使制备的纯相纳米LiNiO2具有更加优良的结晶性能和更佳的电化学特性.添加预烧步骤前后所得最终产物的初始容量分别为151和148mAh·g-1,经过100周的循环,容量衰减到55和118mAh·g-1,容量保持率分别为36.4%和79.7%.原因在于预烧后再进行煅烧降低了阳离子无序度,减少了混杂在Li层中的Ni离子,从而有利于Li离子的扩散,优化了电化学性能.

Molten salt method is applied to synthesis stoichiometric nano-LiNiO2 in rather low temperature and short time.Our results indicate that in the process of preheating the better-crystallized LiNiO2 powder with better electrochemical performances can be produced.The final samples before and after preheating exhibit the initial discharge capacities of 151 and 148 mAh·g-1 respectively.After 100 cycles,they decay to only 55 and 118 mAh·g-1,with capacity retentions being 36.4% and 79.7% respectively.The lowered cation disordering is thought to be favorable for the diffusion of lithium ions,by which the enhanced electrochemial properties can be explained.