(湘潭大学 化学学院 环境友好化学与应用教育部重点实验室，湘潭 411105)
摘 要: 以廉价原材料FeSO4·7H2O为铁源，以蔗糖为碳源，采用固相法合成了锂离子电池正极材料——LiFePO4/C复合材料。用X射线衍射(XRD)、扫描电镜(SEM)和电化学测试技术对不同铁源合成的LiFePO4/C复合材料的结构、形貌和电化学性能进行研究。结果表明：合成的样品具有均一的橄榄石型结构，以FeSO4·7H2O为铁源合成的LiFePO4/C复合材料的循环性能和高倍率放电性能均优于以FeC2O4·2H2O为铁源合成的LiFePO4/C复合材料的；由FeSO4·7H2O合成的LiFePO4/C复合材料的5C倍率放电比容量为105.9 mA∙h/g，经循环30次后，容量仍高达105.2 mA∙h/g。
关键字: LiFePO4/C复合材料；铁源；锂离子电池；正极材料
synthesized by solid-state reaction
（Key Laboratory of Environmentally Friendly Chemistry and Applications,
Ministry of Education, School of Chemistry, Xiangtan University, Xiangtan 411105, China）
Abstract:The lithium ion battery cathode material LiFePO4/C composite was prepared by a solid-state method using the low cost FeSO4∙7H2O as iron source and sucrose as carbon source. The structure, morphology and electrochemical performance of the LiFePO4/C samples prepared with different iron sources were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemistry techniques. The results show that the resultant LiFePO4/C has homogeneous olivine structure. And the capacity and cycle ability of LiFePO4/C prepared from FeSO4·7H2O are higher than that of LiFePO4/C composite synthesized by a traditional solid-state method using FeC2O4∙2H2O as iron source. The capacity is 105.9 mA∙h/g at 5C rate and remained 105.2 mA∙h/g after 30 cycles.
Key words: LiFePO4/C composite; iron source; lithium ion battery; cathode material
