溶胶-凝胶法合成LiFePO_4及其电化学性能研究  

Synthesis of LiFePO_4 for Li-ion battery by sol-gel method and study on its electrochemical performance

作　　者：王恩通[1] 任引哲[2] 

机构地区：[1]山西省吕梁学院化学化工系,山西吕梁033000 [2]山西师范大学化学与材料科学学院,山西临汾041004

出　　处：《电池工业》2011年第3期157-160,171,共5页Chinese Battery Industry

摘　　要：采用溶胶-凝胶法合成锂离子电池正极材料LiFePO4,并用X射线衍射、充放电循环测试、循环伏安法扫描等,研究了LiFePO4的物相结构、表面形貌以及电化学性能等,并探索了合成工艺条件对材料的电化学性能的影响。结果表明,680℃下焙烧得到的材料表现出较好晶体形貌,样品的颗粒大小比较均匀,同时电化学性能较好,10 mA/g的电流密度下首次放电容量为114 mAh/g,20次循环之后容量98 mAh/g,循环性能较好。同时随着电流密度增大,首次放电容量减小,循环效率降低。LiFePO4 was synthesized by sol-gel method with Li2CO3、Fe（NO3）3·9H2O、NH4H2PO4 as raw materials.The prepared LiFePO4 was then characterized by XRD,SEM,CV analysis.The electrochemical properties of the product at different conditions were studied.The results indicated that the prepared olivine LiFePO4 had good electrochemical behavior,and the sample which was sintered at 680 ℃ for 10 h showed the best electrochemical property.Its first discharge capacity was 114 mAh/g with a current density of 10 mA/g,and maintained a discharge capacity of 98 mAh/g after 20 cycles,showed good cycle performance.At the same time,as the current density increased,the initial discharge capacity and cycle efficiency decreased.

关 键 词：锂离子电池 正极材料 溶胶-凝胶法 LIFEPO4 

分 类 号：TM912.9[电气工程—电力电子与电力传动]