• A Vanadium Redox Flow (VRF) battery has two separate tanks, one containing a positive electrolyte and one a negative electrolyte. Both electrolytes consist of the element vanadium dissolved in sulphuric acid, with the vanadium occurring in different oxidation states (valences).
• The battery has a number of battery cells as well. Each of these cells is divided into two chambers separated by a membrane, through which the ions can pass. In each chamber there is a positive or negative electrode. The two electrolytes are pumped through the cells on their side of the membranes.