关键词: 钒酸锂, 淬火, 固相合成, 正极材料

Abstract: With lithium carbonate and vanadic oxide as raw materials,LiV₃O₈ cathode material was synthesized by solid-state reaction with quick quenching in dry freezing air at 600 ℃.Its structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).Results showed that the compound had low crystallinity degree,homogeneous morphology,and small size.Electrochemical performances were measured by charge-discharge cycling,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS).Results indicated that the compound had more Li⁺ insertion/extraction sites and was beneficial to Li⁺ reversible movement.It reached 256 mA•h/g and 189 mA•h/g in the 1st and 30 times cycles at the charge-discharge rate of 0.25 C,respectively.Average discharge capacity of the compound was about 40 mA•h/g higher than that of directly synthesized solid-phase sample.The method is a convenient and effective method for improving the electrochemical performances of LiV₃O₈. 

Key words: LiV₃O₈, quenching, solid-state synthesize, cathode material