Co^3+-modified Surface of LiMn2O4 Spinel for its Improvement of Electrochemical Properties  

作　　者：ZishanZHENG ZilongTANG ZhongtaiZHANG JunbiaoLU WanciSHEN 

机构地区：[1]DepartmentofChemistry,ZhangzhouTeachersCollege,Zhangzhou363000,Pujian,China [2]StateKeyLaboratoryofNewCeramicsandFineProcessing,DepartmentofMaterialsScienceandEngineering.TsinghuaUniversity,Beijing100084,China

出　　处：《Journal of Materials Science & Technology》2003年第4期359-362,共4页材料科学技术（英文版）

基　　金：supported by the Basic Research Fund of Tsinghua University under grant No.JC1999054;‘985’Project of School of Materials Science and Engineering of Tsinghua University;the Scientific Fund of the Education Committee of Fujian Province.

摘　　要：Cobalt was used to modify the surface of spinel LiMn2O4 by a solution technique to produce Co3+-modified surface material (COMSM). Cobalt was only doped into the surface of LiMn2O4 spinel. XPS(X-ray photoelectron spectroscopy) analysis confirms the valence state of Co3+. COMSM has stable spinel structure and can prevent active materials from the corrosion of electrolyte. The ICP(inductively coupled plasma) determination of the spinel dissolution in electrolyte showed the content of Mn dissolved from COMSM was smaller than that from the pure spinel. AC impedance patterns show that the charge-transfer resistance (Ret) for COMSM is smaller than that for pure spinel. The particles of COMSM are bigger in size than those of pure spinel according to the micrographs of SEM(scanning electron microscopy). The determinations of the electrochemical characterization show that COMSM has both good cycling performance and high initial capacity of 124.1 mA/h at an average capacity loss of 0.19 mAh/g per cycle.Cobalt was used to modify the surface of spinel LiMn2O4 by a solution technique to produce Co3+-modified surface material (COMSM). Cobalt was only doped into the surface of LiMn2O4 spinel. XPS(X-ray photoelectron spectroscopy) analysis confirms the valence state of Co3+. COMSM has stable spinel structure and can prevent active materials from the corrosion of electrolyte. The ICP(inductively coupled plasma) determination of the spinel dissolution in electrolyte showed the content of Mn dissolved from COMSM was smaller than that from the pure spinel. AC impedance patterns show that the charge-transfer resistance (Ret) for COMSM is smaller than that for pure spinel. The particles of COMSM are bigger in size than those of pure spinel according to the micrographs of SEM(scanning electron microscopy). The determinations of the electrochemical characterization show that COMSM has both good cycling performance and high initial capacity of 124.1 mA/h at an average capacity loss of 0.19 mAh/g per cycle.

关 键 词：Lithium ion batteries LIMN2O4 Cation doping COATING 

分 类 号：TM912[电气工程—电力电子与电力传动] TM910.3