摘要
采用水热法制备出层状锂锰氧化物LiMnO2。通过X射线衍射研究了LiMnO2的结构,通过粒径分布测试和恒电流充放电方法研究了LiOH浓度、产物的粒径分布及煅烧温度对LiMnO2的电化学性能的影响。研究表明,制备的LiMnO2具有正交晶系结构;通过控制浓度可以达到控制粒径的目的。当LiOH浓度分别为5mol/L、6mol/L、7mol/L时,LiMnO2的粒径分布d(0.5)分别为8.551μm、7.424μm、8.272μm。电化学测试表明,当粒径分布d(0.5)为7.424μm的LiMnO2经700℃煅烧后,其比容量和循环性能有显著的改善。以理论容量0.1C倍率放电时,其首次放电比容量为152mAhg-1,20次循环后,比容量为136mAhg-1,其保电率为90%。
Lithium manganese orthorhombic LiMnO2 had been prepared by hydrothermal method. The structure of LiMnO2 were studied by XRD. Effects of LiOH concentration, product particle size and calcination temperature on the eclectrochemical properties of LiMnO2 were investigated by XRD, particle size distribution and constant current charge-discharge test. The results showed that the product was LiMnO2 with orthorthombic structure; The particle size of the product was controlled by LiOH concentration. When the LiOH concentration were 5 mol/L, 6 mol/L and 7 mol/L, the average particle size d（0. 5） of LiMnO2 were 8. 551 μm, 7. 424 btm and 8. 272μm. Electrochemical tests showed that when the average particle size d（0.5） of LiMnO2 was 7. 424 μm and was calcined at 700℃,the specific capacity and cyclic properties of the product were greatly improved; First specific discharge capacity of the material LiMnO2 was 152 mAhg-1 , and 136 mAhg 1 after 20 cycles. The capacity retention was 90%.
出处
《金属功能材料》
CAS
2012年第2期26-30,共5页
Metallic Functional Materials
基金
安徽省教育厅自然科学研究项目(050601D2)
关键词
LIMNO2
水热法
LiOH浓度
电化学性能
LiMnO2
hydrothermal method
LiOH concentration
electrochemical performances
