Li3+xV2(PO4)3的合成及电化学性能研究

Synthesis and Electrochemical Performance of Li3+xV2(PO4)3

摘要:

通过碳热还原法合成了化学计量比的Li3V2(PO4)3和富锂的锂离子电池正极材料Li3+xV2(PO4)3 (x=0.02, 0.04, 0.05, 0.06)。利用XRD、SEM和电化学测试对Li3+xV2(PO4)3进行研究表明：所合成的试样均为单斜晶系结构，无杂相存在；SEM测试发现，掺锂可以明显改善Li3V2(PO4)3一次颗粒表面的结构和形貌；电化学性能测试表明，随着掺锂量的提高，试样的循环性能变好。通过研究发现，Li3.04V2(PO4)3具有较高的初始容量和良好的循环性能

关键词:锂离子电池;Li3V2(PO4)3;掺杂;碳热还原

Abstract:

Stoichiometric and lithium-rich Li3+xV2(PO4)3 (x=0.02,0.04,0.05,0.06) for lithium batteries was prepared by a carbon-thermal reduction (CTR) process. The properties of the Li3+xV2(PO4)3 were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical measurement. The results show that the samples have monoclinic structure, without any other phases in samples. The SEM images exhibit that the surface structure of the primary particles is clearly improved. The measurement of electrochemical performance shows that the cycle ability and the first discharge capacity are also improved with the doping of lithium

Key words:lithium batteries; Li3V2(PO4)3; doping; carbon-thermal reduction