富锂正极材料Li_(1+x)[Ni_(0.36)Mn_(0.64)]_(1-x)O_2的制备及电化学性能研究  

Investigation of Preparation and Electrochemical Performance of Lithium-rich Cathode Materials Li_(1+x)[Ni_(0.36)Mn_(0.64)]_(1-x)O_2

作　　者：钟盛文[1] 梅文捷 李栋[1] 金柱[1] 刘熙林 陈鹏[1] 胡经纬[1] 

机构地区：[1]江西理工大学材料科学与工程学院江西省动力电池及其材料重点实验室,赣州341000

出　　处：《材料导报》2015年第12期10-14,共5页Materials Reports

基　　金：国家自然科学基金(51372104);江西省青年科学基金计划(20142BAB216018);江西理工大学研究生创新基金(3104100041)

摘　　要：采用氢氧化物共沉淀-高温固相焙烧法合成了富锂正极材料 Li1＋x [Ni0.36 Mn0.64]1-x O2（x=0.12,0.15,0.18,0.2）。采用 XRD 表征其结构,SEM 表征其形貌,恒电流充放电和循环伏安测试其电化学性能。其中,XRD 结果表明各样品都具有α-NaFeO2型层状结构。结果表明：室温下以30 mA/g 的电流密度,在4.6~2.75 V 的电压范围内充放电,x=0.15的首次放电比容量为237.9 mAh/g,经50次循环后容量保持率为98%。研究发现,层状富锂镍锰正极材料中的 Li2 MnO3组分在充放电过程中会逐渐向尖晶石相转变,这是容量衰减的主要原因。Lithium rich Li1 ＋x [Ni0.3 6 Mn0.64 ]1 -x O2 （x=0.12,0.1 5,0.18,0.2）cathode materials were synthe-sized via co-precipitation and high temperature sintering.The crystal structure,morphology,and electrochemical per-formance were characterized by XRD,SEM,galvanostatic charge-discharge cycling and cyclic voltammetry,respec-tively.The XRD results indicated that all samples were based on anα-NaFeO2 layered structure.The electrochemical performance utilizing this as-prepared optimum sample material as the cathode generated high specific discharge capaci-ty 237.9 mAh/g and capacity retention ratio 98% at 30 mA/g after 50 cycles at room temperature,in the voltage range of 4.6-2.75 V.The study emphasized that,Li2 MnO3 doping stabilizes layered lithium rich nickel and manga-nese oxide cathode material transforms into spinel phase during the cycling,which leads to poor cycling stability.

关 键 词：锂离子电池 正极材料 LI2 MNO3 无钴 

分 类 号：O64[理学—物理化学]