| Li3V2(PO4)3 material was synthesized by sol-gel method, and The surface morphologies and structures was observed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The electrochemical performances were characterized by charge-discharge test, cycle voltammogram(CV) and electrochemical impedance spectroscopy (EIS). The effects of different synthesis temperatures, lithium sources, pH values and reaction ambiences on the structures and electrochemical performance of Li3V2(PO4)3 material.Li3V2(PO4)3 material was synthesized by sol-gel method using citric acid and LiOH·H2O as a chelating agent and lithium source, respectively, and the effect of different synthesis temperatures, pH values and reaction ambiences on the structures and electrochemical performance of Li3V2(PO4)3 material. The results show that the dry gel was pre-baked at 300℃for 4 h, then baked at 600℃for 8 h in H2/Ar ambience, yielding Li3V2(PO4)3 material which has better crystallinity, uniform particle sizes and electrochemical performance. The initial discharge capacity reaches 130 mAh·g-1 between 3.0 V-4.2 V at 0.1 C discharge rate.The initial discharge capacity reaches 128 mAh·g-1 between 2.5 V-4.2 V at 1 C discharge rate, and the discharge capacity after 40 cycles is 126 mAh·g-1, and the capacity retention is 98 %, which exhibits better cycle performance. The pH values of solution obviously affect the discharge capacity, and Li3V2(PO4)3 material synthesized at pH=3 has higher discharge capacity than that of material synthesized at pH=8.Li3V2(PO4)3 material was synthesized by sol-gel method using citric acid and LiF as a chelating agent and lithium source, respectively, and the effect of different synthesis temperatures and pH values on the structures and electrochemical performance of Li3V2(PO4)3 material. The results indicate that all samples have high phase purity and are well crystallized when the synthesis temperature is between 600℃-800℃. The samples synthsized 800℃have the best initial discharge capacity which reaches 111 mAh·g-1 between 2.5 V-4.2 V at 1 C discharge rate ,and the discharge capacity after 36 cycles is 82 mAh·g-1, and the capacity retention is 74 %. The initial discharge capacity of samples synthsized 600℃is 91 mAh·g-1, and the discharge capacity after 30 cycles at 1 C discharge rate is 84 mAh·g-1, and the capacity retention is 92 %. The samples synthsized 700℃has better cycle performance, and the initial discharge capacity is 108 mAh·g-1, and the discharge capacity after 70 cycles is 106 mAh·g-1 at 1 C discharge rate, and the capacity retention is 98%. As a result, the samples synthsized 700℃has better electrochemical performance, and the pH value has almost no effects on the structure, but it has significant effects on the electrochemical performance.CV results reveal that the oxidation peak and reduction peak lapped well from the two scanning process,meaning that the samples has good cycle performance, and the separation of peak potentials between the oxidation peak and reduction peak decreases at the twice scanning process, indicating that the reversibility of the samples becomes better. EIS results exhibit that electrochemical reaction resistance decreases with increasing of synthesis temperatures of samples...
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