干冷空气淬火制备钒酸锂材料性能研究  

Research on material performance of LiV_3O_8 synthesized with quenching in dry freezing atmosphere

作　　者：刘永梅[1] 李惠娟[1] 倪杰[1] 

机构地区：[1]西南林业大学西南山地森林资源保育与利用重点实验室,云南昆明650224

出　　处：《无机盐工业》2011年第9期30-33,共4页Inorganic Chemicals Industry

基　　金：云南省教育厅基金资助项目(2010Y291)

摘　　要：利用固相合成干冷空气淬火法,以碳酸锂和五氧化二钒作原料,在600℃下合成了钒酸锂(LiV3O8)正极材料。用X射线衍射(XRD)和扫描电镜(SEM)表征了钒酸锂材料的结构和形貌,结果表明产物结晶度较低,形貌均匀,尺寸较小。用充放电循环、循环伏安及电化学交流阻抗测试其电性能,结果表明样品有更多的锂离子嵌脱位置和更小的锂离子扩散电阻。在0.25C充放电倍率下,其首次和30次循环的放电容量分别达到256mA.h/g和189mA.h/g,每次循环平均放电容量高出直接固相合成样品约40mA.h/g。该方法是提高钒酸锂材料性能的简便有效方法。With lithium carbonate and vanadic oxide as raw materials,LiV3O8 cathode material was synthesized by solid-state reaction with quick quenching in dry freezing air at 600 ℃.Its structure and morphology were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.Results showed that the compound had low crystallinity degree,homogeneous morphology,and small size.Electrochemical performances were measured by charge-discharge cycling,cyclic voltammetry（CV）,and electrochemical impedance spectroscopy（EIS）.Results indicated that the compound had more Li＋ insertion/extraction sites and was beneficial to Li＋ reversible movement.It reached 256 mA·h/g and 189 mA·h/g in the 1st and 30 times cycles at the charge-discharge rate of 0.25 C,respectively.Average discharge capacity of the compound was about 40 mA·h/g higher than that of directly synthesized solid-phase sample.The method is a convenient and effective method for improving the electrochemical performances of LiV3O8.

关 键 词：钒酸锂 淬火 固相合成 正极材料 

分 类 号：TQ131.11[化学工程—无机化工] O646[理学—物理化学]