一步固相法批量制备LiFePO_4/C的研究  

Research of LiFePO_4/C batch prepared by one-step solid-state synthesis

作　　者：邬春阳[1] 余红明[1] 曹高劭[1] 赵新兵[1] 

机构地区：[1]浙江大学材料科学与工程学系,浙江杭州310027

出　　处：《电源技术》2011年第1期18-21,共4页Chinese Journal of Power Sources

基　　金：浙江省科技计划项目(2007C21100)

摘　　要：以磷酸铁为铁源,氢氧化锂为锂源,可溶性淀粉为还原剂和碳源,先通过球磨混料与喷雾干燥获得成分均匀的前驱体,再采用一步固相法,在氮气保护推板窑中合成了LiFePO4/C正极材料,进行了日产100kg级的批量制备研究。结果表明合成的LiFePO4/C材料的碳含量为3.2%～3.4%(质量分数),材料粒度D50为2.1μm,颗粒结晶完整、尺寸均匀,具有单一的橄榄石型晶体结构。电化学测试表明,三步升温方法合成的LiFePO4/C正极材料具有较高的比容量,在0.1、1、5C,充放电倍率下首次放电比容量分别为157、127、97mAh/g。100次循环后,1C和5C放电比容量分别为126mAh/g和94mAh/g,表现出良好的高倍率循环性能。Precursor was prepared using iron phosphate,lithium hydroxide and tragantine by ball milling spray drying.LiFePO4/C was produced by one-step solid-state reaction in a N2-filled pushed slab kiln with an output of 100 kg per day.The results show LiFePO4 is the olivine type structure with a carbon content of 3.2%～3.4%,a D50 particle size is 2.1μm and a tap density of 0.95 g/mL.The electrochemical measurements show that LiFePO4/C synthesized by three-steps heating exhibits high specific capacities of 157,127,97 mAh/g at charge and discharge rates of 0.1,1 C and 5 C respectively.The sample also exhibits a good rate capability.After 100 cycles at 1 C and 5 C,the specific capacities of 126 mAh/g and 94 mAh/g are still maintained.

关 键 词：LIFEPO4 一步固相法 批量制备 升温方法 

分 类 号：TM912.9[电气工程—电力电子与电力传动]