磷酸亚铁锂-磷酸钒锂复合材料制备方法研究  

The Preparation of the Composite Materials LiFePO_4-Li_3V_2(PO_4)_3

作　　者：郭孝东[1] 唐红[1] 徐瑞[1] 唐艳[1] 钟本和[1] 

机构地区：[1]四川大学化学工程学院教育部磷资源利用中心,四川成都610065

出　　处：《高校化学工程学报》2012年第3期531-535,共5页Journal of Chemical Engineering of Chinese Universities

基　　金：国家科技支撑计划(2007BAQ01055);国家自然科学基金(50574063)

摘　　要：以固相法制备出了磷酸亚铁锂-磷酸钒锂复合正极材料。采用X-射线衍射仪(XRD)、电子扫面电镜(SEM)、激光粒度分析仪、碳硫分析仪以及X-光电子能谱仪等对制备出的复合材料进行表征,发现该材料以磷酸亚铁锂和磷酸钒锂的晶形结构为主,其中有少量的杂质成分;该材料颗粒粒度较细、粒度分布窄且均匀,颗粒表面光滑、碳包裹状况良好,同其它方法制备的复合材料比较在碳含量差不多的情况下具有较优的导电率。对材料进行了电化学性能表征认为该材料的电化学性能比较优异,0.1 C放电容量达到190 mA h g 1以上,10 C可以达到120 mA h g 1,20 C放电容量仍有85 mA h g 1且循环稳定性均较好;1 C进行1000次循环之后仍然保持120 mA h g 1的容量,具有较高的实用价值。The LiFePO4-Li3V2（PO4）3 composite cathode materials were prepared by solid method. X-ray diffractometer, scanning electron microscopy, laser granulometer, carbon sulfur analyzer and X-ray photoelectron spectroscopy apparatus were employed respectively to characterize the prepared composite materials. The crystal structure shows that the LiFePO4 and Li3V2（PO4）3 are main constituents but with trace impurities. The particles of the composite material grains are very small and its particle size distribution is very uniform and narrow; the smooth surfaces of the composite material grains are formed by the fine carbon coating layer. Compared with other LiFePO4-Li3V2（PO4）3 composite cathode materials prepared by othex methods, this materials have better electronic conductivity under the condition of with similar carbon content. The electrochemical properties of the prepared materials were tested, its discharge capacity is more than 190 mA.h.g-1, 120 mA.h.g-1, 85 mA.h-g-1at 0.1 C, 10 C and 20 C, respectively; When the material was discharged at 1 C for 1000 times, its capacity can still remain 120 mA.h.g-1, so it has a high practical application value.

关 键 词：磷酸亚铁锂 磷酸钒锂 复合材料 固相法 

分 类 号：TM205.1[一般工业技术—材料科学与工程]