RTX Corporation
IN-SITU ELECTROLYTE PREPARATION IN FLOW BATTERY

Abstract:

A method of in-situ electrolyte preparation in a flow battery includes providing a vanadium-based electrolyte solution having vanadium ions of predominantly vanadium V.sup.4+ to a first electrode and a second electrode of at least one cell of a flow battery. The vanadium V.sup.4+ at the first electrode is converted to vanadium V.sup.3+ and the vanadium V.sup.4+ at the second electrode is converted to vanadium V.sup.5+ by providing electrical energy to the electrodes. A reducing agent is then provided to the vanadium V.sup.5+ at the second electrode to reduce the V.sup.5+ to vanadium V.sup.4+. The vanadium V.sup.3+ at the first electrode is then converted to vanadium V.sup.2+ and the vanadium V.sup.4+ at the second electrode is then converted to vanadium V.sup.5+ by providing electrical energy to the electrodes. A simple method to produce predominantly vanadium V.sup.4+ electrolyte from a V.sup.5+ source, such as V.sub.2O.sub.5, is also taught.