Research On Modified Li₃V₂(PO₄)₃ Cathode Materials For Lithium-ion Battery

The modified Li3V2(PO4)3 is synthetized using sol-gel method, using XRD and SEM to analysis the structure and microcosmic morphology of the produces; The charge-discharge performances at different current rates are tested using the landt test system. The effects of the ratio of lithium and vanadium,calcining temperature,carbon content,pH,sintering time,lithium sources and doping metal ions on the structure,microcosmic morphology and electrochemical proformance of Li3V2(PO4)3 material are seriously researched.The results shows that:using Li2CO3 as the lithium source, with lithium and vanadium at the molar ratio of 3.1:2, calcining at the temperature of 750℃, sintering time to last 6h, the cathode material of Li3V2(PO4)3/C synthetized in the above conditions which first discharge capacity is 126 mAh·g-1 at rate of 0.1 C and possesses the best cycle performance; The high rate of charge-discharge capacity and cycle performance of the samples doped Sn4+ and Mo3+ are not obviously improved.