| In this paper Lithium-ion battery cathode material Li3V2(PO4)3 was synthesized by sol-gel method. Sol process was optimized, and the effects of calcining time and temperature on the components and electrochemical properties of products were investigated. The optimum process conditon of synthesizing Li3V2(PO4)3 is: the initial concentration of sol was 0.1 mol·L-1, ultrasonic dispersing time was 1.5 h, braizing temperature was 50℃, reaction time is 5 h, calcining temperature was 750℃, calcining time was 8 h.The influence of surfactant on the performances of Li3V2(PO4)3 material was discussed. Surface active agent may prevent original particles from reuniting because it can notably reduce surface tention of particles and increase the Zeta potential of precursor in preparation of materials. The results of electrochemical performance testing show that the cathode material Li3V2(PO4)3 has higher charge-discharge capacity and better capacity retention when surfactant was added. The results of SEM indicat that OP-10 may act as dispersants to Li3V2(PO4)3, appropriate amount of OP-10 may greatly improve the reuniting phenomenon of Li3V2(PO4)3 particles.The research into improving the electronic and ion conductivity of battery cathode material was curried out in this paper. Ti4+ was doped in Li3V2(PO4)3 and Li3V2(PO4)3/TiO2 composite material was prepared. The materials were characterized by XRD, IR, SEM, accompanied with charge/discharge curves,electrochemical impedance spectroscopy(EIS), the results show that the doped Ti4+ increase the Li3V2 (PO4) 3 crystal cell volume, which is helpful for the freely filling and embedding of lithium ion, the charge/discharge process show a trendency of transiting to single-phase reaction mechanism; The Li3V2(PO4)3/TiO2 composite material displays excellent cyclic stability. The reason lies in the stable chemical property of TiO2, which can inhibit particles growing up and protected the electrolyte and cathode material contacting directly.
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