Li-rich layered Li1.18Ni0.15Co0.15Mn0.52O2 were prepared by sol-gel method,and characterized by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and scanning electron microscope(SEM), respectively.XRD results shows that the material belongs to layeredα-NaFeO2 structure,XPS confirms that the valence of Ni,Co,Mn was +2,+3 and +4,respectively.SEM shows that the material exists as loose micron-sized aggregates,being composed of primary grains with diameter of 200~400 nm.The electrochemistry performance of the material shows similar charge-discharge curves and different capacities at different electrolytes.Especially at the electrolyte with LiPF6 in a mixture of erhylene carbonate(EC),dimethylcarbonate(DMC) and ethyl methyl carbonate (EMC)with a volume ratio of 1∶1∶8,the material shows a more complete reaction,and the capacity is 331.4 mAh·g-1 and 233 mAh·g-1 at the initial charge and discharge,respectively.%采用溶胶-凝胶法制备了富锂层状材料Li1.18Ni0.15Co0.15Mn0.52O2.通过 X射线衍射仪(XRD)、X-射线光电子能谱(XPS)和扫描电子显微镜(SEM)分别对材料的结构、形貌进行了分析.XRD结果表明,材料属α-NaFeO2型层状结构;XPS结果表明,材料中的Ni,Co和Mn的价态分别为+2,+3和+4价;SEM结果表明,材料颗粒尺寸分布在200~400 nm,且颗粒之间分散比较均匀,无明显的团聚现象;电化学测试结果表明,材料在使用不同电解液进行充放电时,曲线的形状相似,但是充放电容量有所不同.其中在1 mol·L-1LiPF6作为溶质,碳酸亚乙酯(EC)∶碳酸二甲酯(DMC)∶碳酸甲乙酯(EMC)=1∶1∶8(V/V)电解液作用下,材料反应更加完全、彻底,进而使得首次充电及放电容量分别为331.4 mAh·g-1和233.6 mAh·g-1.
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