Technology Outline (Process Description)

Vanadium redox flow battery (VRFB) exploits the ability of vanadium, which can exist in different oxidation states, to store renewable energy and provide uninterrupted supply of electrical energy. It consists of an electrochemical reactor containing an array of VRFB cells along with positive and negative electrolyte tanks, both containing vanadium ion in aqueous acidic solution. The positive electrolyte tank contains VO2+ and VO2+ in charged and discharged states, whereas the negative electrolyte tank contains V2+ and V3+ in the charged and discharged states of the VRFB. The positive and negative electrolytes initially containing a specific vanadium ion concentration in charged states are circulated through the electrochemical reactor for generating electrical energy. Once the stored electrical energy in the electrolyte is utilized (or electrolytes discharge), the electrical energy from renewable sources (preferably) can be used to charge the electrolytes by circulating it in the electrochemical reactor. It is interesting to note that this is a closed loop flow and the electrolyte can ideally be used for infinite number of charge-discharge cycles.