Effect of electrolytic MnO_2 pretreatment on performance of as-prepared LiMn_2O_4  

电解二氧化锰预处理对制备锰酸锂性能的影响(英文)

作　　者：赵于前[1] 蒋庆来[2] 王伟刚[3] 杜柯[3] 胡国荣[3] 

机构地区：[1]中南大学地球科学与信息物理学院,长沙410083 [2]中南大学粉末冶金研究院,长沙410083 [3]中南大学冶金科学与工程学院,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第5期1146-1150,共5页中国有色金属学报（英文版）

基　　金：Project (61172184) supported by the National Natural Science Foundation of China;Project (2007BAE12B01) supported by the National Key Technology R&D Program of China

摘　　要：To investigate the effect of electrolytic MnO2 （EMD） on the performance of LiMn2O4, several pretreatment methods, such as acid treating, presintering and impregnating with chromic salt, were used. The pretreated EMD and prepared LiMn2O4 were characterized by X-ray diffraction and inductively coupled plasma emission spectrometry. Charge and discharge tests of Li/LiMn2O4 batteries were also employed to evaluate electrochemical performance. The experimental results show that inorganic impurity contents in EMD decrease remarkably after acid treating; presintering EMD can remove adsorbent water and organic impurity, enlarge pore space and increase active reaction sites; pre-doping chromium in EMD can form more homogenous compound substance LiCr0.05Mn1.95O4, which shows better structural stability and capacity retention.分别采用酸洗、预烧、浸渍掺铬的方式对电解二氧化锰(EMD)进行预处理,研究EMD预处理对制备锰酸锂性能的影响。采用XRD、ICP等手段对预处理的EMD及制备的锰酸锂进行表征,并通过Li/LiMn2O4电池的充放电测试对其电化学性能进行评估。结果表明,酸洗后EMD中的钠、硫等无机杂质含量显著降低;预烧能够有效去除EMD吸附的水分和有机杂质,扩大孔径,增多反应活性位点;对EMD进行浸渍掺铬的预处理,能够得到更加均质的掺铬锰酸锂材料LiCr0.05Mn1.95O4,并表现出较好的结构稳定性及容量保持率。

关 键 词：lithium-ion batteries cathode material LIMN2O4 MNO2 

分 类 号：O614.111[理学—无机化学]