Research progress in preparation of electrolyte for all-vanadium redox flow battery

All-vanadium redox flow battery (VRFB), as a large energy storage battery, has aroused great concern of scholars at home and abroad. The electrolyte, as the active material of VRFB, has been the research focus. The preparation technology of electrolyte is an extremely important part of VRFB, and it is the key to commercial application of VRFB. In this work, the preparation methods of VRFB electrolyte are reviewed, with emphasis on chemical reduction, electrolysis, solvent extraction and ion exchange resin. The principles, technological processes, advantages and disadvantages of each method are briefly described. The effects of different additives on high concentration electrolyte are also introduced. Finally, the development of vanadium electrolyte preparation technology is prospected.