正极材料磷酸亚铁锂的共沉淀合成和Mn^(2+)掺杂的研究

Research on Co-Precipitation Synthesis and Mn^(2+) Doping of Cathode Materials-LiFePO_4

研究了以氢氧化锂、硫酸亚铁铵和磷酸氢二铵为原料,利用液相共沉淀法制备LiFePO4正极材料和掺杂Mn2+的LiFePO4改性正极材料,并对其进行XRD、SEM分析和电化学性能测试。分析得出,利用液相共沉淀法掺杂Mn2+的正极材料的初始放电比容量为132.9 mAhg-1,且循环10次后,容量仍有124.5 mAhg-1,容量衰减率仅为6.32%。表明少量Mn2+的掺杂没有改变LiFe-PO4的晶体结构,且使材料的电化学性能有所提高。

This paper studies LiFePO4 cathode materials and Mn^2＋-doped LiFePO4 denatured cathode material prepared by liquid co-precipitation method with lithium hydroxide, ammonium ferrous sulfate and di-ammonium phosphate as raw materials. Their samples are analyzed by XRD and SEM and their electrochemical performances are tested. The analytical and testing results indicate that the initial discharge specific capacity of Mn^2＋-doped cathode material prepared by liquid co-precipitation method is 132.9 mAhg^-1 , and that after the circulations for 10 times, its capacity is still 124.5 mAhg^-1, with its attenuation rate of 6.30%, whereby indicating that a small amount of Mn^2＋ doping can not change LiFePO4 crystal structure but improve electrochemical performances of material.