以抗坏血酸为碳源微波合成LiFePO_4/C及电化学性能  

Synthesis and Electrochemical Performance of LiFePO_4/C Composite Prepared by Microwave Method Using Ascorbic Acid as Carbon Source

作　　者：傅鹏立[1] 谷书华[1] 王力臻[1,2] 张勇[1] 

机构地区：[1]郑州轻工业学院,河南郑州450002 [2]河南省表界面科学重点实验室,河南郑州450002

出　　处：《热加工工艺》2011年第14期78-80,83,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(21001097);河南省基础与前沿技术研究项目(092300410124)

摘　　要：以抗坏血酸(VC)为碳源微波加热合成了LiFePO4/C复合材料。采用X射线衍射、扫描电镜、电导率测试和恒流充放电等方法对材料的结构、形貌、电导率及电化学性能进行表征,考察了VC加入量对所合成材料电化学性能的影响。结果表明:VC能有效抑制Fe2+的氧化;当添加VC为10 wt%,微波功率为640W,加热8min时,得到的LiFePO4/C材料电化学性能最优;放电倍率为0.2C和2C时首次放电比容量分别为137、97mAh/g,10次循环后容量保持率分别达95%和81%。LiFePO4 /C composite was prepared by microwave method using ascorbic acid（VC） as carbon source.The phase structure,surface morphology,conductivity and electrochemical performance of LiFePO4/C composite were characterized by XRD,SEM,conductivity test and galvanostatic charge-discharge,respectively,and the effects of VC doping content on the properties of LiFePO4 /C composite were studied.The results show that the oxidation of Fe2＋ is efficiently prevented by VC.The optimal technological condition is ： VC adding amount 10wt%,microwave power 640 W,and heating time 8 min.Under the condition,the sample has excellent electro-chemical performance.The discharge capacity under the discharge rate of 0.2C and 2C is 137 and 97 mAh/g,and the capacity retention rate after 10th cycle is 95% and 81%,respectively.

关 键 词：LIFEPO4/C复合材料 抗坏血酸 微波法 电导率 

分 类 号：TM912.9[电气工程—电力电子与电力传动]