电化学合成磷酸铁锂正极材料的前驱体

以NH4H2PO4、锂盐和纯铁为主要原料,采用电化学法合成磷酸锂铁前驱体,再通过磷酸锂铁前驱体合成锂离子电池正极材料LiFePO4/C。通过X射线衍射(XRD)、扫描电镜(SEM)及充放电性能测试等方法对其晶体结构、微观形貌和电化学性能进行分析研究。结果表明,LiFePO4/C具有单一的橄榄石型晶体结构。其中在无水乙醇溶剂中合成的LiFePO4/C正极材料粒径细小且分布均匀,具有最好的电化学性能,在0.2C的放电电流下,首次放电比容量达到142.3mAh/g,充放电循环30次后放电比容量仍保持在141.2mAh/g。

Electrochemical Synthesis of LiFePO4 Cathode Materials Precursor

LiFePO4 precursor was synthesized by electrochemical method using NH4H2PO4,lithium salt and pure iron as main raw material,and lithium ion battery positive electrode material LiFePO4/C was synthesized by LiFePO4 precursor.The crystalline structure,morphology and electrochemical performances of LiFePO4/C were investigated by X-ray diffraction,scanning electromicroscope,and charge-discharge measurements.The results show that LiFePO4/C is simple pure phase olivine-type crystal structure.It is noted that the LiFePO4/C composite cathode materials have small and uniform particle sizes,and thus excellent electrochemical performance with the first discharge specific capacity of 142.3mAh/g at the rate of 0.2C.After 30times cycling,the discharge specific capacity is 141.2mAh/g.