不同组分下富锂正极材料xLi_2MnO_3·(1-x)LiNi_(0.5)Mn_(0.5)O_2(x=0.1-0.8)的晶体结构与电化学性能  

Crystal Structure and Electrochemical Performance of Lithium-Rich Cathode Materials xLi_2MnO_3·(1-x)LiNi_(0.5)Mn_(0.5)O_2(x=0.1-0.8)

作　　者：陈来[1] 陈实[1,2] 胡道中[3] 苏岳锋[1,2] 李维康[1] 王昭[1] 包丽颖[1,2] 吴锋[1,2] 

机构地区：[1]北京理工大学化工与环境学院,环境科学与工程北京市重点实验室,北京100081 [2]国家高技术绿色材料发展中心,北京100081 [3]中国北方车辆研究所,北京100072

出　　处：《物理化学学报》2014年第3期467-475,共9页Acta Physico-Chimica Sinica

基　　金：国家重点基础研究发展规划项目(973)(2009CB220100);国家自然科学基金(51102018,21103011);国家高技术研究发展计划项目(863)(2011AA11A235,SQ2010AA1123116001);北京理工大学重大项目培育专项计划项目(2013CX01003)资助~~

摘　　要：采用溶胶-凝胶法制备了一系列富锂锰基正极材料xLi2MnO3?(1-x)LiNi0.5Mn0.5O2(x=0.1-0.8),通过X射线衍射(XRD)仪,扫描电子显微镜(SEM)和电化学测试等检测手段表征了所得样品的晶体结构与电化学性能,研究了不同组分下富锂材料的结构与电化学性能.结果表明:Li2MnO3组分含量较高时,材料的首次放电容量较高,但循环稳定性较差;该组分含量较少时,所得样品中出现尖晶石杂相,且放电容量较低,但循环稳定性较好;综合来看,x=0.5时材料的电化学性能最优.x=0.4,0.6时材料也表现出了较好的电化学性能,值得关注.A series of lithium-rich cathode materials, xLi2MnO3？（1-x）LiNi0.5Mn0.5O2 （x=0.1-0.8）, were successfully synthesized by a sol-gel method. X-ray diffraction, scanning electron microscopy, and electrochemical tests were used to investigate the crystal structure, morphology, and electrochemical performance of the as-synthesized materials, respectively. The results showed that the materials with higher Li2MnO3 content had higher initial discharge capacity but poorer cycle stability, while the materials with lower Li2MnO3 content showed lower discharge capacity but better cycle stability, and the spinel impurity phase was also found. Based on the data, the optimal electrochemical properties were obtained when x=0.5 in xLi2MnO3＆#183; （1-x）LiNi0.5Mn0.5O2. Moreover, the electrochemical properties were also worthy of attention when x=0.4, 0.6.

关 键 词：锂离子电池 正极材料 LI2MNO3 晶体结构 电化学性能 LI2MNO3 

分 类 号：TM912[电气工程—电力电子与电力传动]