摘要
采用溶胶-凝胶法,以Li2CO3、V2O5、NH4H2PO4、柠檬酸、Ni(OH)2·H2O为原料成功合成了正极材料Li3V2(PO4)3及其掺Ni化合物。Rietveld精修结果显示在Ni掺杂量不超过0.15时,样品均为纯相。X射线衍射(XRD)结果给出,随着镍掺杂量的增加,a轴和c轴及晶胞体积都有所下降。对样品Li3V2-xNix(PO4)3电导率的测试结果显示,Ni掺杂后样品的电子导电性均有所提高。室温下在0.1C和3C充放电条件下,镍掺杂Li3V1.95Ni0.05(PO4)3正极材料首次放电比容量分别达到177.2mAh/g和136.6mAh/g,在3C倍率下100次循环后容量保持率达到94.2%,这些性能都优于未掺杂样品和其他镍掺杂量的样品。
Ni-doped Li3V2-xNix （PO4）3 compounds were prepared successfully by sol-gel process with Li2CO3, V2O5. NH4H2PO4, citric acid, and Ni（OH）2·H2O as the reactant. The results of Rietveld refinement analysis indicate that single-phase Li3V2-xNix（PO4）3 with monoclinic structure can be obtained for x 〈0.15. X-ray photoelectron spectroscopy analysis suggests that a- axis, c-axis and the cell volume decrease with the increasing of Ni content. There is a large increase in electrical conductivity even with Ni doping. Ni doped Li3V1.95Ni0.05（PO4）3 can deliver the initial capacity of 177.2 mAh/g and 136.6 mAh/g at 0.1 C and 3 C respectively and 94.2% capacity retention can still be held after 100 cycles at 3 C rate.
出处
《电源技术》
CAS
CSCD
北大核心
2009年第5期401-405,共5页
Chinese Journal of Power Sources
基金
国家自然科学基金(50772039)
广东省自然科学基金重点项目(07118058)
作者简介
何智峰（1983-），男,湖南省人，硕士研究生，主要研究方向为锂离子电池正极材料。
