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Monoclinic Li3V2(PO4)3 is a highly promising cathode material for ithium ion batteries because it has high operating voltage,good ion mobility and high reversible capacity.Hydrothermal method is a versatile method for preparing crystalline particles.Its advantages include simple synthetic process,easy scale-up,energy efficient,and environmental friendly.In this work,Li3V2(PO4)3 was synthesized by a simple hydrothermal method using oxalic acid as both reduction agent and carbon sources.In this route,NH4VO3,NH4H2PO4,LiOH·H2O,and (COOH)2·2H2O were used as starting materials.The property of Li3V2(PO4)3 was investigated by X-ray diffraction (XRD),scanning electron microscopy (SEM),and electrochemical measurement.XRD studies showed that the prepared Li3V2(PO4)3 had the same monoclinic structure with a space group (P21/n) as that synthesized by conventional solid-state reaction.SEM image exhibited that the particle size was about 0.5 μm with narrow size distribution.Electrochemical test showed that the initial charge and discharge capacities of Li3V2(PO4)3 powder at 0.5 C was 135,130 mAh·g- 1,respectively.After 50 cycles,the prepared Li3V2(PO4)3 exhibited discharge capacities of about 126 m A g-1 at 0.5 C charge/discharge rates in the range of 3.0-4.2 V.The results indicated that the hydrothermal method was a promising method for synthesizing Li3V2(PO4)3 material with high electrochemical performance.