Mg^2＋掺杂对锂离子正极材料Li3V2（PO4）3的影响

随着市场对锂离子电池(LIB)需求的日趋增长,对电极活性物质的要求也在朝着高能量密度、低成本、安全稳定、环境友好的方向努力,其中正极材料相对负极材料的发展较为缓慢,成为制约LIB发展的瓶颈。NASICON结构的Li3V2(PO4)3属于单斜晶系,相对金属锂具有很高的电势,理论容量高达19

Performance and structure of doped-Mg-Li3V2(PO4)3 cathode material for lithium ion batteries

Li3V2(PO4)3 doped with Mg2 particles were prepared by a novel method from drying the precursor by vacuum distillation,then two steps ball-milling and two steps sintering it.The particle size,structure and morphology of samples were characterized by and particle size distribution(PSD),X-ray diffraction(XRD),scanning electron microscopy(SEM).Electrochemical behaviors were characterized by galvanostatic charge/discharge and cyclic voltammetry.The results showed that the particle size of products was increased by adding small amount of Mg in Li3V2(PO4)3,but the crystal structure not changed comparing with Li3V2(PO4)3 without Mg2 .The sample with nMg:nLi=0.025 showed better performances in terms of the specific discharge capacity and cycle stability.The improved electrochemical properties of the(Li0.95Mg0.025)3V2(PO4)3 samples were attributed to the better electronic conductivity.