锂电池用Ag_2V_4O_(11)正极材料性能研究  

Study on the performance of Ag_2V_4O_(11) positive materials for lithium batteries

作　　者：曹晓雨[1] 谢玲玲[1] 詹晖[2] 周运鸿[2] 

机构地区：[1]河南工业大学化学化工学院,河南郑州450001 [2]武汉大学化学与分子科学学院,湖北武汉430072

出　　处：《电池工业》2008年第3期152-156,共5页Chinese Battery Industry

摘　　要：以Ag2CO3和NH4VO3为原料,通过流变相反应法制备了锂电池正极材料Ag2V4O11。采用X射线衍射(XRD)和恒流充放电技术表征了产物的结构和电化学性能;同时利用非现场X射线衍射(ex-situ XRD)和电化学阻抗谱(EIS)研究了放电特性和循环性能。结果表明,500℃制备的流变相产物放电容量高,倍率性能好;单质银在放电过程中的析出是其倍率放电性能优异的主要原因,而Ag2V4O11结构不可逆性是其循环性能差的根源。Ag2V4O11 phase was successfully prepared fwith Ag2CO3 and NH4VO3 by the rheological phase reaction method. The structure and electrochemical properties of the thus-synthesized products were characterized by X-ray diffraction （XRD） and galvanostatic discharge-charge techniques. Ex-situ XRD and electrochemical impedance spectra （EIS） measures were taken in the investigation of the origin of the capacity fading. The results indicated that the theological phase product obtained at 500℃ displayed a high discharge capacity and excellent rate-capability. The formation of metallic silver during the discharge process was the main reason of the excellent rate-capability, and the structural irreversibility of Ag2V4O11 was the origin of its capacity-fading.

关 键 词：锂电池 正极材料 Ag2V4O11 倍率性能 容量衰减机理 

分 类 号：TM911[电气工程—电力电子与电力传动]