碳热还原法制备LiFePO_4/C及其电化学性能的研究  

Synthesis of LiFePO_4 by carbothermal reduction method and its electrochemical performance

作　　者：尹艳红[1,2] 闫林林[1,2] 范志娟[1,2] 谷继峰[1,2] 杨书廷[1,2] 

机构地区：[1]河南师范大学化学与环境科学学院,河南新乡453002 [2]新能源工程技术研究中心(河南师范大学),河南新乡453002

出　　处：《电源技术》2010年第9期878-880,共3页Chinese Journal of Power Sources

基　　金：河南省重点科技攻关项目(072102230008)

摘　　要：采用半固相高温碳热还原方法,以C2H4OOLi.2 H2O、NH4H2PO4、便宜的Fe2O3作为初始原料,以β-环糊精做为碳源和还原剂合成了LiFePO4/C材料。碳含量能够影响颗粒的大小和材料的电化学性能,通过X射线衍射(XRD)、扫描电镜(SEM)等对产物的结构和形貌进行了表征,同时通过充放电实验测试电化学性能和交流阻抗等手段研究了LiFe-PO4/C脱嵌机理。结果显示:在合适的碳量下用碳热还原反应制备的样品颗粒均匀细小并且电化学性能优越。在0.3 C倍率首次充放电比容量可达到162.4 mAg/h,循环35次后容量保持率达到99%,振实密度高达1.6 g/cm3左右。The electroactive LiFePO4/C composite was synthesized by a half high temperature carborthermal reduction using C2H4OOLi.2 H2O,NH4H2PO4 and cheap Fe2O3 as the initial materials and β-cyclodextrin as carbon sources.The carbon content could affect the morphology and electrochemical performance of LiFePO4/C composite.The product characterization of the structure and morphology of the product were studied by XRD and SEM,respectively.The process of intercalation and removal of Li-ion were investigated by AC impedance method.The results show that the samples synthesized by half solid state carborthermal reduction with optimal carbon content have the small-est particle size and the best electrochemical performance.At a rate of 0.3 C,it can deliver an initial discharge ca-pacity of 162.4 mAh/g with capacity retention up to 99% after 35 cycles,and the tap density is around 1.6 g/cm3.

关 键 词：磷酸铁锂 半固相碳热还原 Β-环糊精 

分 类 号：TM912.9[电气工程—电力电子与电力传动]