Storage Vanadium Redox Flow Battery Electrode Materials

Electrode materials of storing energy vanadium flow battery (abbreviation: vanadium battery), including their choosing, preparation and modification, were studied in paper. It was found during research that graphitization process can raise intensity of carbon-fibre, while moving average graphitization degree of carbon felt was 24.8% after 2300℃ graphitization process. Its resistivity would decline to 1/3 1/6 of that. Electrochemic performance of graphite felt was examined with CV curve, AC impedance curve and exchange current in heat-treatment process, and it was found that 550°C was the best heat-treatment temperature in 2 hours. If graphite felt heat-treated would been acid-treated for 10 hours, its electrochemic performance could rise. Graphite felt could been modified by H₂IrCl₆ when it was used to anode of vanadium battery, and it would put up good electrochemic performance and reversibility.In separate acid-treatment process, the best acid-treatment time was not above 2 hours. Electrochemic performance of graphite felt would go down with acid-treatment time if it was above 2 hours. Physical performance of graphite felt would not changed and intensity of graphite felt electrode could been ensured in acid-treatment process. Graphite felt, which was acid-treated in best time, could be used to cathode material of vanadium battery for its good reactive.In studying on titanium electrode and titanium electrode assembly, Iridium-Tantalum-Titanium electrode was a kind of good performance and sitting easily electrode and as anode of vanadium battery, the charge and discharge density could achieve 40mA·cm^-2 without separating out oxygen. In charging, oxygen was easily separated out on the first kind of titanium electrode assembly and its coat fell out lightly. While the second kind of titanium electrode assembly had biggish resistance.Charge & discharge efficiency of static vanadium batteries, which were assembled with graphite felt electrodes treated with kinds of conditions, was above 90% in experiment. Through hundreds of charge & discharge cycles, capacities of vanadium batteries would not go down and those electrodes had not eroded by acid. Those vanadium batteries assembled with titanium electrodes and titanium electrodes assembly were not fit to technical parameter of industrial vanadium battery for lowcharge & discharge efficiency.