Physical Properties and Electrochemical Performance of LiNi_xMn_(2-x)O_4 Cathode Materials Prepared using a Precipitation Method  

作　　者：Guoguang WAN Jianming WANG Wenqu MAO Jianqing ZHANG Chunan CAO 

机构地区：[1]Department of Chemistry, Zhejiang University, Hangzhou 310027, China [2]State Key Laboratory for Corrosion and Protection, Institute of Metal Research, CAS, Shenyang 110016, China

出　　处：《Journal of Materials Science & Technology》2006年第1期19-24,共6页材料科学技术（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(No.59902004).The authors also gratefully acknowledge the financial support of the State Key Laboratory for Corrosion and Protection of China.

摘　　要：To improve the cycle performance of spinel LiMn204 as the cathode material of 4 V class Li secondary batteries, LiNixMn2-xO4 （x=0-0.3） samples were prepared using a simple precipitation method, and the effects of Ni doping on the physical properties and electrochemical performance of the samples were investigated using various methods. All LiNixMn2-xO4 （x=0-0.3） compounds show a single spinel phase, and the lattice parameter （a）, the unit cell volume （v） and particle size decrease with increasing Ni content. The results of the electrochemical experiments showed that the initial charge-discharge capacity of LiNixMn2-xO4 samples in the 3.0-4.4 V range decreases with increasing Ni content except for pure LiMn2O4; however, the capacity in the 4.4-4.9 V range increases with the increasing Ni content. For spinel samples Ni substitution can contribute to the improvement of their cycle performance due to the formation of the stronger Ni-O bond, homogeneous morphology, and sub-micron sized particles, and the sample with x=0.05 has larger peak currents, higher initial capacity and better cycling capability due to its lower electrochemical and diffusion polarization than those of other samples.To improve the cycle performance of spinel LiMn204 as the cathode material of 4 V class Li secondary batteries, LiNixMn2-xO4 （x=0-0.3） samples were prepared using a simple precipitation method, and the effects of Ni doping on the physical properties and electrochemical performance of the samples were investigated using various methods. All LiNixMn2-xO4 （x=0-0.3） compounds show a single spinel phase, and the lattice parameter （a）, the unit cell volume （v） and particle size decrease with increasing Ni content. The results of the electrochemical experiments showed that the initial charge-discharge capacity of LiNixMn2-xO4 samples in the 3.0-4.4 V range decreases with increasing Ni content except for pure LiMn2O4; however, the capacity in the 4.4-4.9 V range increases with the increasing Ni content. For spinel samples Ni substitution can contribute to the improvement of their cycle performance due to the formation of the stronger Ni-O bond, homogeneous morphology, and sub-micron sized particles, and the sample with x=0.05 has larger peak currents, higher initial capacity and better cycling capability due to its lower electrochemical and diffusion polarization than those of other samples.

关 键 词：Ni-substituted LiMn2O4 Electrochemical performance Electrochemical impedance spectroscopy 

分 类 号：TM912.2[电气工程—电力电子与电力传动] O646.54[理学—物理化学]