V <sub> 2 </ Sub> O <sub> 5 </ Sub> Gel Preparation And Electrochemical Performance

In the paper, the development of supercapacitor and the research progress of V₂O₅ were reviewed in detail. In order to improve the capacity of V₂O₅, the preparation processes, structural characterization modification of materials and electrochemical properties were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), TGA, Fourier transform infrared spectroscopy (FT-IR), Cyclic Voltammetry (CV) and Discharge-Charge.The V₂O₅ xerogel was prepared by melting and quenching, and the preparation conditions were investigated. The result showed that the samples had high capacity when the mass rate of the water to V₂O₅ was 33:1, the melting temperature was in the range of 800-850℃ and the temperature retention time was 15 minute. The capacity was 25.6% improved when carbons were mixed into the samples with the rate of 1:1 at the current rate of 2C. The result also showed that the heat-treatment temperature and time had great influence on the electrochemical property of the sample, the performance of the sample was better when it was heat-treated for 20 hours at 120℃.The solvent exchange and frozen-dry were adopted to solve the problem that the structure collapses in the dry course of gel. The aerogel-like sample with high surface of 36.67m²/g was prepared. The sample had a specific capacity of 278mAh/g at 0.1C rate, and better current rate characteristic compared to xerogel; The sample prepared with frozen-dry had a network structure made up with random tiny fibres which could be seen under the electron microscope, and the sample was amorphous hydrate with high capacity and good reversibility. It had a specific capacity of 278mAh/g at 0.1C.