A method and systems are provided for utilizing black powder to form an electrolyte for a flow battery. In an exemplary method the black powder is heated under an inert atmosphere to form Fe.sub.3O.sub.4. The Fe.sub.3O.sub.4 is dissolved in an acid solution to form an electrolyte solution. A ratio of iron (II) to iron (III) is adjusted by a redox process.

Methods and systems are provided for a rebalancing reactor of a flow battery system. In one example, a pH of a battery electrolyte may be maintained by the rebalancing reactor by applying a negative potential to a catalyst bed of the rebalancing reactor. A performance of the rebalancing reactor may further be maintained by treating the catalyst bed with deionized water.

A redox flow battery system includes an anolyte having chromium ions in solution; a catholyte having iron ions in solution, where a molar ratio of chromium in the anolyte to iron in the catholyte is at least 1.25; a first electrode in contact with the anolyte; a second electrode in contact with the catholyte; and a separator separating the anolyte from the catholyte.

Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

An object of the present invention is to improve the performance of a metal-air battery. The metal-air battery includes an air electrode, an anode, and an electrolyte sandwiched between the air electrode and the anode. The air electrode includes a co-continuous body having a three dimensional network structure formed by an integrated plurality of nanostructures having branches. A magnesium alloy is used for the anode, and a weak acidic salt containing no chloride ion or a salt considered to have a buffering capacity is used for the electrolyte. Consequently, the present invention can efficiently utilize electrons and suppress passivation and self corrosion of the anode, thereby improving the performance of the metal-air battery.

This disclosure provides novel batteries, e.g., redox flow batteries, and methods of making and operating batteries. Certain embodiments include redox flow battery comprising: a housing; a first electrode disposed in the housing; a second electrode disposed in the housing and facing the first electrode, the first electrode is spaced from the second electrode by a gap without an intervening ion selective membrane; and a fluid conveyance mechanism connected to the housing and configured to convey an electrolyte across the gap between the first electrode and the second electrode.

Stable and high performance positive and negative electrolytes compositions to be used in redox flow battery systems are described. The redox flow battery system, comprises: at least one rechargeable cell comprising a positive electrolyte, a negative electrolyte, and an ionically conductive membrane positioned between the positive electrolyte and the negative electrolyte, the positive electrolyte in contact with a positive electrode, and the negative electrolyte in contact with a negative electrode. The positive electrolyte consists essentially of water, a first amino acid, an inorganic acid, an iron precursor, a supporting electrolyte, and optionally a boric acid. The negative electrolyte consists essentially of water, the iron precursor, the supporting electrolyte, and a negative electrolyte additive. The iron precursor is FeCl.sub.2, FeCl.sub.3, FeSO.sub.4, Fe.sub.2(SO.sub.4).sub.3, FeO, Fe, Fe.sub.2O.sub.3, or combinations thereof. The supporting electrolyte is LiCl, NaCl, Na.sub.2SO.sub.4, KCl, NH.sub.4Cl, or combinations thereof. The negative electrolyte additive is boric acid or a combination of the boric acid and a second amino acid.

A rechargeable manganese battery includes: (1) a first electrode including a porous, conductive support; (2) a second electrode including a catalyst support and a catalyst disposed over the catalyst support; and (3) an electrolyte disposed between the first electrode and the second electrode to support reversible precipitation and dissolution of manganese at the first electrode and reversible evolution and oxidation of hydrogen at the second electrode.

An electrical energy storage device and a method of forming such electrical energy storage device. The electrical energy storage device includes an electrolyte that is arranged to dissipate energy when subjected to external mechanical load applied to the electrical energy storage device. The electrolyte includes a polymer matrix of at least two crosslinked structures, including a first polymeric material and a second polymeric material; and an electrolytic solution retained by the polymer matrix.

Described are flow electrochemical cells and systems using flow electrochemical cells that carry simultaneous CO.sub.2 capture and electrical energy storage. The flow electrochemical cells comprise a negative electrode configured to be in fluid communication with alkaline negative electrolyte, a positive electrode configured to be in fluid communication with acidic positive electrolyte, a first ion-exchange membrane in contact with the negative electrode, a second ion-exchange membrane in contact with the positive electrode, and an inert intermediate neutralyte layer between the first ion-exchange membrane and the second ion-exchange membrane.