LiFeO_2包覆锂离子正极材料Li[Li_(0.2)Mn_(0.54)Ni_(0.13)Co_(0.13)]O_2制备及性能表征  

Synthesis and performance characterization of LiFeO_2 coating Li-[Li_(0.2)Mn_(0.54)Ni_(0.13)Co_(0.13)]O_2 cathode materials for lithium-ion batteries

作　　者：陈佚[1] 吴伯荣[1] 赵章宏 陶丹 李佳[1] 

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]高平唐一新能源科技有限公司,山西晋城048400

出　　处：《电源技术》2014年第6期1018-1021,共4页Chinese Journal of Power Sources

摘　　要：采用溶胶-凝胶工艺在Li[Li0.2Mn0.54Ni0.13Co0.13]O2表面包覆LiFeO2,并用扫描电镜(SEM),X-射线衍射(XRD),EIS和恒电流充放电等方法研究了不同包覆量的LiFeO2包覆对Li[Li0.2Mn0.54Ni0.13Co0.13]O2结构和电化学性能的影响。XRD、SEM实验数据表明,该材料具有层状α-NaFeO2结构,包覆后材料结构没有变化,表面覆盖上一层纳米级别的颗粒。电化学性能测试结果表明,质量分数1%LiFeO2包覆能显著改善Li[Li0.2Mn0.54Ni0.13Co0.13]O2材料在高截止电压(4.8 V)下的循环性能和倍率性能,EIS研究结果显示其界面阻抗明显减小,电子电导率得到提高,从而提高电化学性能。LiFeO2 coating Li[Li0.2Mn0.54Ni0.13Co0.13]O2 was prepared by sol-gel process. The effect of LiFeO2 coating quantity on the structure and electrochemical performance of Li[Li0.2Mn0.54Ni0.13Co0.13]O2 was characterized by scanning electron microscope（SEM）, X-ray diffraction（XRD）, electrochemical impedance spectroscopy（EIS） and galvanostatic charge-discharge tests. The XRD and SEM electrochemical data show that coated material structure does not change with α- NaFeO2 layered structure, the surface covered with a layer of nanometer-scale particles. Electrochemical tests suggest that the cycle performance and rate capability of lwt% LiFeO2-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 can be greatly improved under a high cutoff voltage range of 4.8 V; EIS results confirm that interfacial impedance is significantly reduced, and the electronic conductivity is improved, thereby enhancing the electrochemical performance.

关 键 词：锂离子电池 LiFeO2 Li[Li0 2Mn0 54Ni0 13Co0 13]O2 包覆 

分 类 号：TM912.9[电气工程—电力电子与电力传动]