Study On Preparation And Electrochemical Performance Of Li₃V₂（PO₄）₃/C As Cathode For Lithium-Ion Batteries

Peer work about lithium-ion battery cathode materials had been reviewed at the beginning, then Li3V2(PO4)3/C was prepared by carbothermal reduction reaction using different vanadium sources. The structure features and morphology of Li3V2(PO4)3 were indicated by X-ray diffraction and scanning electron microscopy, the electrochemical performances were investigated by galvanostatic current charge-discharge, cyclic voltammetry, electrochemical impedance spectroscopy, the effects of sintering temperature, calcination time, the molar ratio of lithium and vanadium element, carbon source on the physical performance and electrochemical behavior of Li3V2(PO4)3 were studied and the synthesis conditions were optimized.Li3V2(PO4)3 was prepared by carbothermal reduction reaction using V2O3 as vanadium source. We researched the effect of technological conditions on the crystal structure and electrochemical performance, the results showed that the mixture was calcined at 800℃ for 12h, the molar ratio of n(Li):n(V)=3.05:2, graphite as carbon source displayed the better electrochemical performance. In the voltage range of 3.0-4.3V, its first discharge specific capacity was 93.5mAh/g at 0.1C and displayed good cycle performance.Li3V2(PO4)3 was prepared by carbothermal reduction reaction using V2O5 as vanadium source, the sample was investigated by X-ray diffraction, which revealed single phase Li3V2(PO4)3 can be synthesized with good and pure crystal, the intensity of diffraction was sharp. We researched the effect of technological conditions on the crystal structure and electrochemical performance, the results showed that the mixture using sucrose as carbon source was calcined at 850℃ for 12h, and the molar ratio of n(Li):n(V)=3.05:2 exhibited an excellent electrochemical performance. The first discharge capacity of the cathode was 121.3mAh/g and it retained 117.8mAh/g after charge/discharge for 30 cycles at 0.1 C rate.