原料对合成LiMn_2O_4电化学性能的影响  

Effect of Raw Materials on the Electrochemical Properties of LiMn_2O_4

作　　者：刘金练[1] 吴显明[1,2] 陈上[1,2] 麦发任[1] 李长安[1] 

机构地区：[1]吉首大学化学化工学院,湖南吉首416000 [2]湘西自治州矿产与新材料技术创新服务中心,湖南吉首416000

出　　处：《精细化工》2011年第11期1095-1098,共4页Fine Chemicals

基　　金：湖南省科技厅资助项目(2009FJ3045)~~

摘　　要：采用固相法分别以不同原料合成尖晶石LiMn2O4。采用X射线衍射、扫描电子显微镜、循环伏安及恒电流充放电等技术检测和分析合成产物的物相、形貌及电化学性能。研究表明,与采用电解MnO2为原料合成的LiMn2 O4相比,采用Mn3 O4为原料合成的LiMn2 O4粉末X射线衍射峰强度更大,室温下以0.2 C倍率充放电循环30次时,首次放电比容量和容量保持率分别为128.7 mA.h/g和98.4%,高于以电解MnO2为原料合成LiMn2 O4的123.7 mA.h/g和85.0%。55℃循环时,采用Mn3 O4为原料合成的LiMn2 O4容量保持率比采用电解MnO2为原料合成LiMn2O4的高10.7%。Spinel LiMn2O4 was synthesized via solid state process with different raw materials. The phase identification, surface morphology and electrochemical properties of the synthesized powders were characterized by means of X-ray diffraction, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge experiments. The results show that LiMn2O4 powders prepared from Mn3O4 show better crystallization than those prepared from electrolytic MnO2. When cycled at room temperature for 30 times at the charge-discharge rate of 0.2 C, LiMn2O4 prepared from Mn3O4 shows the initial discharge specific capacity and capacity retention of 128.7 mA · h/g and 98. 4%, respectively, which are considerably higher than 123.7 mA · h/g and 85.0% for LiMn2O4 prepared from electrolytic MnO2. The capacity retention of LiMn2O4 prepared from Mn3O4 is 10.7% higher than that of the one prepared from electrolytic MnO2 when cycled at 55 ℃.

关 键 词：锂离子电池 固相法 锰酸锂 有机电化学与工业 

分 类 号：TM912.9[电气工程—电力电子与电力传动]