Study On Electrode Materials For All Vanadium Redox Flow Battery

All vanadium redox flow battery is a new-style and environmentally energy storagebattery that has many characteristis such as perfect charge/discharge performance、Theelectrode don’t participate in response、 theoretically unlimited life、 simpleoperation.Therefore,it has attracted much attention.However,there are still some questions tobe solved not only on the thery but also on the practical application.For example,many factorsthat effect the performance of vanadium battery should be considered,such as theconcentration of the electrelgtic liquid、electrode reation、the performance of electordmaterials.At present,the development of vanadium batter is abstructed by the choice of theelectord materials. Metal electrodes、 composite condutre plastic eletrode and carbon classelectrode can be used to made electrode.Graphite rod and graphite felt were introduced as carbon class eletrode in this paper.Electrochemical properties of V（IV）/V（V） on different electrodes is studied in this paper withcyclic voltammograms,EIS,otc.Tere are seveal results. In the0.65-1.4V scanning potentialrange,there are two characteristic peaks，The peak potential value corresponding in V （IV）/V（V） for the oxidation of the electric peak and reduction peaks. the peak current add with theincrease of the scanning speed. And, the increasing distance of the peak potential lead todecline of the reversibility. To get the better electrochemical propertise and reversibce,the0.05v/s is the best scanning speed.100times of scanning later, the current conservation rate ofthe Graphite rod was still as high as95%.The experiment results showed that graphite rodelectrode had a relatively better electrochemistry performance which made it suitable for theVO₂⁺/VO²⁺electrode’s positive electrode material.Electrochemical propertise of V（IV）/V（V）is studied with cyclic voltammograms method on acid treaded graphite felt electrode、electrochemical treated felt graphite electrode、CoCl₂modifide graphite electrode,prussianblue treated graphite electrode. V（IV）/V（V） has the best electrochemical propertise ongraphite felt electrode treated in550℃2hours heat treament.Eectrochemical propertise ofV（IV）/V（V） is enhanced but the reversibility is falling on the electrochemical treated feltgraphite. CoCl₂modifide graphite electrode has little electro-catalysis effect to oxidationprocess of V（IV）/V（V）,but has electro-catalysis effect to reduction process of V（IV）/V（V）.Theactinity of V（IV）/V（V） has been enhanced on the prussian blue treaded graphite electrode. The resistane of after heating graphite felt electrode is obviously less than before by themethod of EIS.The best temperature is550℃.With charge-discharge technology of the V （IV）/V （V） single electrode in graphiteelectrode of great charge and discharge properties. When the chage current and dischargecurrent is1mA and10mA, charging termination voltage and discharge termination voltageis1.9V and0.2V respectively, along with the increase of cycling times, charge and dischargeplatform are consistent, explain electrode is stability.