Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: A method for a redox flow battery may include, interrupting cycling of the redox flow battery, including charging the redox flow battery to a threshold charge condition, draining positive and negative electrolyte from the redox flow battery, circulating a wash solution through the redox flow battery, and returning the positive and negative electrolyte to the redox flow battery, and resuming cycling of the redox flow battery. In this way, contamination of the redox flow battery system can be reduced, thereby prolonging the life and increasing performance of the redox flow battery system.

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: A leaf spring compression system comprising a mechanical assembly for securing a plurality of leaf springs on a battery cell stack of a flow battery system is disclosed. The cell stack may, comprise: a plurality of cells stacked together to form a flow battery; and a compression system comprising at least two tie rods extending through the plurality of cells clamping a spring acting at opposite ends to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods. In this way, the compression system may exert uniform loading on the battery cell stack, while minimizing deflection of pressure plates attached to the cell stack.

Abstract: Methods and systems are provided which maintain the positive and negative electrolyte pH and stability of a redox flow battery through the use of electrochemical rebalancing cells. The electrochemical cells may be activated by applying an electrical load to affect changes to the pH of the electrolytes. The use of the electrochemical cells improves long term performance stability redox flow batteries by decreasing and/or eliminating Fe(OH)3 precipitation formation.

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: A method of operating an iron redox flow battery system may comprise fluidly coupling a plating electrode of an iron redox flow battery cell to a plating electrolyte; fluidly coupling a redox electrode of the iron redox flow battery cell to a redox electrolyte; fluidly coupling a ductile plating additive to one or both of the plating electrolyte and the redox electrolyte; and increasing an amount of the ductile plating additive to the plating electrolyte in response to an increase in the plating stress at the plating electrode. In this way, ductile Fe can be plated on the negative electrode, and the performance, reliability and efficiency of the iron redox flow battery can be maintained. In addition, iron can be more rapidly produced and plated at the plating electrode, thereby achieving a higher charging rate for all iron flow batteries.

Abstract: Methods and systems are provided for manufacturing a membrane separator for a redox flow battery. In one example, the membrane separator is fabricate by a calendering process. The membrane separator may be configured with a polymer network to provide selectivity for ion transport across the membrane separator. The membrane separator may be further adapted with an integrated spacer in contact with a negative electrolyte.

Abstract: Methods and systems are provided for a redox flow battery system. In one example, the redox flow battery is adapted with an additive included in a battery electrolyte and an anion exchange membrane separator dividing positive electrolyte from negative electrolyte. An overall system cost of the battery system may be reduced while a storage capacity, energy density and performance may be increased.

Abstract: Methods and systems are provided for manufacturing a bipolar plate for a redox flow battery. In one example, the bipolar plate is fabricated by a roll-to-roll process. The bipolar plate includes a non-conductive substrate that is coupled to a negative electrode on a first surface and coupled to a positive electrode on a second surface, the first surface opposite of the second surface.

Abstract: An iron redox flow battery system, comprising a redox electrode, a plating electrolyte tank, a plating electrode, a redox electrolyte tank with additional acid additives that may be introduced into the electrolytes in response to electrolyte pH. The acid additives may act to suppress undesired chemical reactions that create losses within the battery and may be added in response to sensor indications of these reactions.

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: Methods and systems are provided which maintain the positive and negative electrolyte pH and stability of a redox flow battery through the use of electrochemical rebalancing cells. The electrochemical cells may be activated by applying an electrical load to affect changes to the pH of the electrolytes. The use of the electrochemical cells improves long term performance stability redox flow batteries by decreasing and/or eliminating Fe(OH)3 precipitation formation.

Abstract: Methods and systems are provided which maintain the positive and negative electrolyte pH and stability of a redox flow battery through the use of electrochemical rebalancing cells. The electrochemical cells may be activated by applying an electrical load to affect changes to the pH of the electrolytes. The use of the electrochemical cells improves long term performance stability redox flow batteries by decreasing and/or eliminating Fe(OH)3 precipitation formation.

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: A method of cleansing a redox flow battery system may include operating the redox flow battery system in a charge, discharge, or idle mode, and responsive to a redox flow battery capacity being less than a threshold battery capacity, mixing the positive electrolyte with the negative electrolyte. In this way, battery capacity degradation following cyclic charging and discharging of the redox flow battery system can be substantially reduced.

Abstract: A rebalancing reactor for a redox flow battery system may include a first side through which hydrogen gas is flowed, a second side through which electrolyte from the redox flow battery system is flowed, and a porous layer separating and fluidly coupled to the first side and the second side, wherein, the hydrogen gas and the electrolyte are fluidly contacted at a surface of the porous layer, and a pressure drop across the second side is less than a pressure drop across the porous layer. In this way, rebalancing of electrolyte charges in a redox flow battery system may be performed with increased efficiency and cost effectiveness as compared to conventional rebalancing reactors.

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

Abstract: A leaf spring compression system comprising a mechanical assembly for securing a plurality of leaf springs on a battery cell stack of a flow battery system is disclosed. The cell stack may, comprise: a plurality of cells stacked together to form a flow battery; and a compression system comprising at least two tie rods extending through the plurality of cells clamping a spring acting at opposite ends to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods. In this way, the compression system may exert uniform loading on the battery cell stack, while minimizing deflection of pressure plates attached to the cell stack.

Abstract: An iron redox flow battery system, comprising a redox electrode, a plating electrolyte tank, a plating electrode, a redox electrolyte tank with additional acid additives that may be introduced into the electrolytes in response to electrolyte pH. The acid additives may act to suppress undesired chemical reactions that create losses within the battery and may be added in response to sensor indications of these reactions.