锡掺杂磷酸铁锂正极材料制备和电化学性能研究  

Preparation and electrochemical performance of Sn-doped LiFePO_4/C cathode material

作　　者：左晶[1] 赵晓南 代爱萍[1] 康徐伟 

机构地区：[1]西安科技大学化学与化工学院,陕西西安710054 [2]山东鲁碧建材有限公司

出　　处：《无机盐工业》2015年第12期79-82,共4页Inorganic Chemicals Industry

基　　金：西安科技大学大学生创新训练项目(S12111)

摘　　要：用共沉淀法合成了不同锡(Sn)掺杂量的磷酸铁锂复合正极材料(Li Fe_(1-x)Sn_xPO_4/C)。对Li Fe_(1-x)Sn_xPO_4/C进行了X射线衍射(XRD)、扫描电镜(SEM)、激光粒度分析。使用蓝电系统和电化学工作站对Li Fe_(1-x)Sn_xPO_4/C进行了电化学性能分析。实验结果表明,Li Fe_(1-x)Sn_xPO_4/C具有与Li Fe PO_4(标准卡片83-2092)相同的单一橄榄石型晶体结构;锡的掺杂引起晶胞体积收缩,细化了粒径;3%Sn掺杂的Li Fe_(0.97)Sn_(0.03)PO_4/C样品的平均粒径为0.57μm,0.5C下放电容量为156.7 m A·h/g,50次循环后容量保持率为82.9%,这与其具有较小的电化学阻抗结果相吻合。Different proportions of tin（Sn） doped Li Fe1-xSnxPO4/C composite cathode material were synthesized via coprecipitation method.The obtained materials have been studied by X-ray diffraction,scanning electron microscopy,and laser particle analysis.The electrochemical properties of samples were tested by using the Land system and electrochemical working station.The experiments results showed that the sample had the same olive crystal phase of Li Fe PO4（standard card 83-2092）,which shrink the cell volume,and refine the particle size by Sn doping.Discharge capacity of 3% Sn with the average particle size of 0.57 μm doped Li Fe0.97Sn0.03PO4/C was 156.7 m A·h/g at 0.5 C,the rate of capacity retention still remained 82.9% after50 cycles,which was in accordance with small electrochemical impedance.

关 键 词：锡掺杂 磷酸铁锂 充放电 比容量 

分 类 号：TQ131.11[化学工程—无机化工]