低温固相反应合成Li3V2(PO4)3正极材料及其性能

利用V₂O₅·nH₂O湿凝胶，LiOH·H₂O，NH₄H₂PO₄和C等作原料，通过低温固相还原反应在550 ℃焙烧12 h制备出Li₃V₂(PO₄)₃正极材料。采用XRD，SEM和电化学测试对Li₃V₂(PO₄)₃样品性能进行研究。XRD研究表明本法所合成的Li₃V₂(PO₄)₃同传统的高温固相反应法所合成的Li₃V₂(PO₄)₃一样同属于单斜晶系结构。SEM测试表明所合成的样品平均粒径大小约为0.5 μm且粒径分布较窄。电化学测试表明以0.2 C的倍率放电时，样品的首次放电容量为130 mAh·g^-1，室温下循环30次后其比容量为124 mAh·g^-1。

Cathode Material Li3V2(PO4)3: Low Temperature Solid-state Reaction Synthesis and Performance

Li3V2(PO4)3 cathode material was prepared by lowtemperature solid-state reaction. V2O5·nH2O hydrogel, LiOH ·H2O, NH4H2PO4 and C were used as starting materials to prepare the precursor, and Li3V2(PO4)3 was obtained by sintering the precursor at 550 ℃ for 12 h. The property of the Li3V2(PO4)3 sample was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemicalmeasurement. XRD studies show that the Li3V2(PO4)3 sample obtained has the same monoclinic structure as that synthesized by conventional solid-state reaction. SEM image exhibits that the particle size is about 0.5 μm with narrow size distribution.Electrochemical test shows that the initial discharge capacity of Li3V2(PO4)3 powder is 130 mAh·g-1 at the rate of 0.2 C,and the capacity retains 124 mAh·g-1 after 30 cycles at room temperature.