The electrode material is mainly divided into metal electrode and carbon electrode, wherein the carbon electrode with good stability reflects the greater advantage, and the carbon electrode, graphite felt materials with its advantages of real surface area is much larger than the geometric surface area and occupies the dominant position. The graphite felt were activated by concentrated sulfuric acid by liquid phase oxidation and air oxidation method, that can greatly improve the electrochemical performance of vanadium battery.
The thermal oxidation method has simple process, low consumption, but the operation elasticity is small, not easy to control. The oxidation reaction reagent with concentrated sulfuric acid oxidation method is very dangerous, industrialized production difficult. And the electrochemical oxidation method, the oxidation reaction of moderate, easy to control, treatment effect, and is easy to realize industrialized operation.
The small capacity of the battery has been successfully applied in human life, further research and development of new environmentally friendly battery suitable for large-scale energy storage, development and utilization of new energy sources, will have great social and economic significance. All vanadium redox flow battery can be regarded as the representative of the new energy storage battery, compared with other batteries and it has a unique advantage, and has been the attention of scientists at home and abroad, at present, the vanadium battery has been abroad applied to wind power plant, power station power peaking and solar photovoltaic demonstration operation. But the development of vanadium battery is still limited, the electrode material is a very important factor.
V4+/V5+ of electrochemical activity on the improved redox peak intensity was significantly enhanced and the peak potential is much closer, indicating reversibility has been significantly improved. Without graphite felt surface treatment of materials directly for vanadium battery electrode, because the surface hydrophobicity caused by polarization was so severe that it is difficult to have the charge and discharge platform stability.