A Vanadium Flow Battery is a type of rechargeable battery that uses vanadium ions in different oxidation states to store and release energy. It consists of two electrolyte solutions, each containing vanadium, which are stored in separate tanks. When energy is needed, the solutions are pumped through a cell where a chemical reaction occurs, generating electricity. These batteries are known for their long cycle life and ability to scale up for large energy storage applications. They are particularly useful for storing renewable energy from sources like solar power and wind energy, helping to balance supply and demand in the energy grid.