单斜Li3V2(PO4)3/C复合材料的制备及其电化学性能

The cathode material Li3V2(PO4)3/C was synthesized by a novel soft chemistry method with LiOH•H2O, V2O5, H3PO4 and sucrose as the raw materials. The structure and morphology of products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements, electrochemical properties of samples were investigated by constant current charge-discharge and electrochemical impedence spectroscopy (ETS). The results showed that the sample synthesized at 700 was pure monoclinic Li3V2(PO4)3 with a particle size of 1-2 μm; and it exhibited an initial discharge capacity of 148.2 mAh•g^(-1) under 0.2C rate in the voltage of 3.0-4.5 V, which remained 144 mAh•g^(-1) in the 50th cycle with a capacity retention of 97%, indicating good cycling performance; in addition, the sample had better rate and high temperature performance.