摘要
采用溶胶-凝胶（sol-gel）法制备了颗粒较小（100-300nm）、分布均匀的尖晶石LiCoxMn2-xO4粉体,研究了不同掺杂水平对其结构及电化学性能的影响。结果表明,掺杂少量Co于LiMn2O4中并不改变材料的尖晶石结构;随着Co掺杂量增加,材料结构稳定性提高,极化降低,首次放电比容量逐渐减小,但充放电循环性能却明显改善;在低温（500℃）条件下退火6h后,LiCoxMn2-xO4粉体的放电比容量稍有增加,但对循环性能影响不大;在电流密度0.1mA/cm^2和截止电压3.5-4.4V时,LiCo0.1Mn1.9O4粉体首次放电比容量达123mAh/g,20次循环后的稳定放电比容量为106mAh/g,具有较好的电化学性能。
Spinel LiCo, Mn2-xO4 powder with 100 - 300nm particle size was prepared by sol-gel process and the influence of Co content on its structure and electrochemical properties was investigated. The results show that doping Co in LiCo, Mn2-xO4 does not change its spine structure .The 1st discharge capacity decreases slightly but its cycling property improves obviously for enhancing the structure stability and decreasing the polarization with the increase of Co content. The capacity of LiCoxMn2-xO4 powders after annealing at 500℃ for 6h increases slightly while having no effect on its cycling performance. At the current density of 0. lmA/cm^2 and cut-off voltage of 3.5 - 4.4V, the initial and stable discharge capacity of LiCo0.1 Mn1.9 O4 powder reaches 123mAh/g, and 113mAh/g after 20 cycles, respectively.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2007年第4期38-41,共4页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金项目(20083001)
国家重大基础研究计划项目(ZM200103B01)
河南科技大学青年科研基金项目(2004QN010)
