The vanadium redox battery is a type of rechargeable flow battery

Flow battery

A flow battery is a form of rechargeable battery in which electrolyte containing one or more dissolved electroactive species flows through an electrochemical cell that converts chemical energy directly to electricity...

 that employs vanadium

Vanadium

Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature...

 ions in different oxidation states to store chemical potential energy. The present form (with sulfuric acid electrolytes) was patented by the University of New South Wales

University of New South Wales

The University of New South Wales , is a research-focused university based in Kensington, a suburb in Sydney, New South Wales, Australia...

 in Australia in 1986 An earlier German Patent on a titanium chloride flow battery was registered and granted in July 1954 to Dr. Walter Kango, but most of the development of flow batteries was carried out by NASA researchers in the 1970s.