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: 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 system for a flow cell for a hybrid flow battery, comprising: a redox plate comprising a plurality of electrolyte flow channels; conductive inserts attached to the redox plate between adjacent electrolyte flow channels; a redox electrode attached to a surface of the redox plate; a plating electrode, comprising: a plurality of folded fins with an oscillating cross-section, the plurality of folded fins comprising: a first planar surface; a second planar surface, parallel to the first planar surface; a plurality of ridges intersecting the first and second planar surfaces such that the plurality of ridges divide the first planar surface into a first plurality of strips, and divide the second planar surface into a second plurality of strips; and a membrane barrier. In this way, the capacity and performance of hybrid flow batteries may be maximized, through decreasing the reaction kinetics, mass transport and ohmic resistance losses at both electrodes.

Abstract: In one example, a system for a flow cell for a flow battery, comprising: a first flow field; and a polymeric frame, comprising: a top face; a bottom face, opposite the top face; a first side; a second side, opposite the first side; a first electrolyte inlet located on the top face and the first side of the polymeric frame; a first electrolyte outlet located on the top face and the second side of the polymeric frame; a first electrolyte inlet flow path located within the polymeric frame and coupled to the first electrolyte inlet; and a first electrolyte outlet flow path located within the polymeric frame and coupled to the first electrolyte outlet. In this way, shunt currents may be minimized by increasing the length and/or reducing the cross-sectional area of the electrolyte inlet and electrolyte outlet flow paths.