锰掺杂钴酸锂LiMn_xCo_(1-x)O_2的性能研究  

Studies on the performance of LiMn_xCo_(1-x)O_2 synthesized by doping LiCoO_2 with M n for the Li-ion battery

作　　者：赵黎明[1] 章福平[1] 潘毅[1] 孔令宇[1] 杨旭[1] 江润科[1] 

机构地区：[1]南京大学化学化工学院,南京210093

出　　处：《电池工业》2007年第2期105-108,共4页Chinese Battery Industry

基　　金：南京大学引进人才培养基金(无编号);南京大学分析测试基金资助课题(无编号);江苏海四达集团公司赞助项目(无编号)

摘　　要：采用XRD、循环伏安和恒电流充放电等方法研究了用Mn(NO3)2做锰源掺杂合成的锂离子电池正极材料LiMnxCo1-xO2的结构及其电化学行为。结果表明,以0.5mA/cm2充放电,Li/LiMnxCo1-xO2电池充电容量有所下降;但放电工作电压平台均在3.6V左右,放电容量随着x从0.05增至0.25,从98.88mAh/g下降到55.70mAh/g;与LiCoO2相比,放电容量分别减少了10.6%和49.6%。XRD结果显示,随着x的增加,充放电前后LiMnxCo1-xO2中均含有MnO2的特征峰,充电后相应的晶胞参数c和a分别略有增大和减小。然而,循环伏安结果显示与LiCoO2相比,LiMnxCo1-xO2并没有新的氧化还原峰产生,说明其中的MnO2并未参加充放电反应。In this paper, both the structures and electrochemical behaviors of the LiMnxCo1-xO2 obtained by doping LiCoO2 with Mn from Mn（NO3） 2 have been studied by the XRD, cyclic voltammetry, and constant current charge and discharge. The results show that discharge capacities of the Li/LiMnxCo1-xO2 batteries seem to decrease linear with the increase of x, along with a slight reduction of the corresponding charge capacities. For examples, at the current density 0.5 mA/cm2, with the variations of x from 0.05 to 0.25, the discharge capacities of the batteries Li/LiMnxCo1-xO2 are 98.88 mAh/g and 55.70 mAh/g respectively. Compared these with that of LiCoO2, the capacity losses are 10.6% and 49.6% separately. But the related working voltages of all those Li/LiMnxCo1-xO2 batteries are about 3.6 V, almost the same as that of LiCoO2. Furthermore, with the increment of x, the XRD spectra indicate a little enlargement of the cell parameter c and a small reduction of the cell parameter a, and the presence of MnO2 even though cyclic voltammetry studies reveal that MnO2 does not participate into both the charge and discharge reactions.

关 键 词：锂离子电池 锂电池 锂 锰 Mn(N03)2 LiC002 LiMnxCo1-xO2 

分 类 号：TM911.14[电气工程—电力电子与电力传动]