钛白渣制备复合磷酸铁锂及其电化学性能  

Preparation of LiFePO4 from titanium white slag and its electrochemical properties

作　　者：郭举 贾双珠 GUO Ju;JIA Shuang-zhu(Maotai College,Zunyi Guizhou 564507,China;Guizhou University,Guiyang Guizhou 550025,China;State Key Laboratory for Efficient Utilization of Low-and-Medium-Grade Phosphate Ores and Their Associated Resources,Guiyang Guizhou 550025,China;Qiannan Normal University for Nationalities,Duyun Guizhou 558000,China)

机构地区：[1]茅台学院,贵州遵义564507 [2]贵州大学,贵州贵阳550025 [3]中低品位磷矿及其共伴生资源高效利用国家重点实验室,贵州贵阳550025 [4]黔南州民族师范学院,贵州都匀558000

出　　处：《电源技术》2020年第4期482-484,513,共4页Chinese Journal of Power Sources

基　　金：中低品位磷矿及其共伴生资源高效利用国家重点实验室开放基金课题(WFKF2017-02)。

摘　　要：采用液相水热法制备技术,以钛白渣、碳酸锂、磷酸二氢钠为原料,抗坏血酸为添加剂,在密闭高压反应釜中合成得到了镁掺杂磷酸铁锂复合材料。研究了钛白渣一步制备磷酸铁锂材料过程中,杂质元素的掺入情况及其对复合材料结构、形貌、电化学性能等的影响。电感耦合等离子体光谱仪(ICP)和电镜能谱仪(EDS)分析结果表明,在合成过程中镁成功掺入到复合材料中,制备得到复合材料LiMP04(M代表Fe与Mg);X射线衍射仪(XRD)分析结果表明微量镁的掺入并未对材料结构产生影响;扫描电镜(SEM)结果显示钛白渣制备的复合磷酸铁锂材料形貌为菱形多面体;电化学性能测试结果表明合成的复合材料的首次充放电性能、循环性能和高倍率性能有较大提升,均显著优于高纯硫酸亚铁制备的磷酸铁锂材料性能。Magnesium-doped lithium iron phosphate composites were synthesized in a closed autoclave using titanium dioxide slag,lithium carbonate and sodium dihydrogen phosphate as raw materials and ascorbic acid as additive by liquid-phase hydrothermal method.The effects of impurity elements on the structure,morphology and electrochemical properties of lithium iron phosphate composites prepared from titanium dioxide slag in one step were studied.The results of ICP and EDS analysis show that magnesium is successfully doped into the composites during the synthesis process,and LiMPO4(M stands for Fe and Mg) is prepared.X-ray diffraction(XRD) analysis shows that the doping of trace magnesium has no effect on the structure.The results of scanning electron microscopy(SEM) show that the morphology of composite lithium iron phosphate prepared from titanium dioxide slag is rhombohedral polyhedron,and the electrochemical performance test show that the first charge-discharge performance,cycling performance and high-rate performance of the composite are greatly improved,significantly superior to those of LiFePO4 made by high-purity ferrous sulfate.

关 键 词：钛白渣 磷酸铁锂 镁掺杂 性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]