초록 |
Even though the all-vanadium redox flow battery (VRFB) is considered as one of the most promising candidate for the energy storage system, commercialization of VRFB is hindered due to its high cost. Especially, the cost of vanadium electrolyte takes great portion because of expensive and complex electrolyte production process. Here, for the first time, we propose a simple and effective method to produce impurity-free +3.5 valence state electrolyte for the VRFB by employing catalytic reaction of the reducing agent. Since reaction kinetics and purities of electrolyte are directly related with catalysts and reducing agents, their reaction performances and stabilities were carefully tested with electrochemical analysis and mass analysis. By using the catalytic reaction, V3.5+ electrolyte was successfully produced with excellent cell performance (CE~95%, EE~87%). We believe that the proposed catalytic production of VRFB electrolyte is a breakthrough invention for the VRFB technology. |