| Monoclinic Li3V2(PO4)3 was considered as the most promising candidate for the next generation cathode materials of lithium ion battery for the merit of high theoretical specific capacity and high voltage flat of charge-discharge. However, the discharge performance of the Li3V2(PO4)3 composite at high rates was limited for the poor electronic conductivity. So Li3V2(PO4)3 was limited to be put into commercially used. In this paper, Li3V2(PO4)3 was synthesized by carbothermal reduction. The effects of grind method, sinter method, sinter temperature and times, cut-off voltage of charging on properties of products were investigated.Lithium-ion battery cathode material Li3V2(PO4)3 was synthesized by carbothermal method using LiH2PO4,V2O5 as raw materials and using sucrose as the reduction agent. Properties of the prepared samples under different condition were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), pore size distribution and specific surface area analyzer, optical particle size analyzer and electrochemical methods,electrochemical workstation and constant current charge-discharge test.In Chapter 1, a general introduction is given on following aspects: the development and categories of batteries including lithium-ion batteries, the structure and working mechanism of lithium-ion battery, the usual cathode and negative electrode materials, and the research progress on the Li3V2(PO4)3.In Chapter 2, the author mainly introduces the experimental raw materials, equipment and methods used in the project of this thesis. A detailed description on the process of making a experimental cell is presented. The structural and electrochemical analyses methods are also summarized. The author mainly introdauces the prepared of the Li3V2(PO4)3/C samples.In Chapter 3, monoclinic Li3V2(PO4)3/C composites are successfully synthesized by the carbothermal method using LiH2PO4,V2O5 as raw materials and using sucrose as the reduction agent. Properties of the prepared samples under different condition were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD),pore size distribution and specific surface area analyzer, optical particle size analyzer and electrochemical methods,electrochemical workstation and constant current charge-discharge test. The effects of grind method, sinter method, sinter temperature and times, cut-off voltage of charging on properties of products were investigated systematically. The results showed that the sample synthesized by grind method, at 850℃by one-step heat treatment sintered 16h exhibits the best electrochemical performance.In Chapter 4, the author gives an overview on the originality and the deficiency in this thesis. Some prospects and suggestions of the possible future research directions are pointed out.
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