LiMn_2O_4表面包覆Li_4Ti_5O_(12)的制备及倍率特性(英文)  

Preparation and Rate Property of Li_4Ti_5O_(12)-coated LiMn_2O_4 for Lithium Ion Battery

作　　者：刘东强[1] 吁霁[1] 孙玉恒[1] 何泽珍[1] 刘兴泉[1] 

机构地区：[1]中国科学院成都有机化学研究所

出　　处：《无机化学学报》2007年第1期41-45,共5页Chinese Journal of Inorganic Chemistry

基　　金：中国科学院'西部之光'联合学者基金资助项目

摘　　要：采用固相法合成了尖晶石型LiMn2O4,并通过溶胶-凝胶法制备了不同物质的量的百分比含量Li4Ti5O12包覆的正极材料。X-射线衍射和扫描电镜结果表明,Li4Ti5O12微粒包覆在LiMn2O4的表面没有产生晶体结构的变化。实验电池在室温下,以1C,2C和5C倍率作充放电循环测试;结果表明,与未包覆的LiMn2O4相比,表面包覆Li4Ti5O12微粒的正极材料在高倍率下具有更好的循环稳定性。Spinel LiMn2O4 was prepared by solid-state reaction and coated with different molar ratios of Li4Ti5O12 particles via sol-gel method. The unmodified and surface-modified LiMn2O4 were characterized by XRD and SEM. The results suggest that the Li4Ti5O12 particles have been encapsulated on the surface of the LiMn2O4 without any crystal structural change. To investigate the rate capability of the prepared materials, the experimental batteries were performed under a current rate of 1C, 2C and 5C, respectively, at ambient temperature. The electrochemical results reveal that the Li4Ti5O12-coated LiMn2O4 materials show excellent rate stability compared to the uncoated spinel, especially under 5C rate.

关 键 词：尖晶石型LIMN2O4 表面改性 Li4Ti5O12微粒 倍率特性 

分 类 号：O614.111[理学—无机化学]