All-vanadium sulfate redox flow battery systems have a catholyte and an anolyte comprising an aqueous supporting solution including chloride ions and phosphate ions. The aqueous supporting solution stabilizes and increases the solubility of vanadium species in the electrolyte, allowing an increased vanadium concentration over a desired operating temperature range. According to one example, the chloride ions are provided by MgCl.sub.2, and the phosphate ions are provided by (NH.sub.4).sub.2HPO.sub.4.

All-vanadium sulfate redox flow battery systems have a catholyte and an anolyte comprising an aqueous supporting solution including chloride ions and phosphate ions. The aqueous supporting solution stabilizes and increases the solubility of vanadium species in the electrolyte, allowing an increased vanadium concentration over a desired operating temperature range. According to one example, the chloride ions are provided by MgCl.sub.2, and the phosphate ions are provided by (NH.sub.4).sub.2HPO.sub.4.

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.

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.

This invention provides a system and a method for safe production of electrolyte at required concentration on site on demand where occasionally only water is needed to be filled up. The system includes two main units: a saturated electrolyte unit and a diluted electrolyte unit.

This invention provides a system and a method for safe production of electrolyte at required concentration on site on demand where occasionally only water is needed to be filled up. The system includes two main units: a saturated electrolyte unit and a diluted electrolyte unit.

A flow battery system includes a first tank including a hydrogen reactant, a second tank including a bromine electrolyte, and at least one cell including a first electrolyte side operably connected to the first tank and a second electrolyte side operably connected to the second tank. The battery system further includes a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.

A flow battery system includes a first tank including a hydrogen reactant, a second tank including a bromine electrolyte, and at least one cell including a first electrolyte side operably connected to the first tank and a second electrolyte side operably connected to the second tank. The battery system further includes a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.

Systems and methods for energy storage system are provided. The system includes a particle regeneration subsystem for applying electrical energy to regenerate metallic particulate fuel; a fuel storage subsystem for storing metallic particulate fuel, the fuel storage subsystem in fluid communication with the particle regeneration subsystem; and a power generation subsystem for producing electrical energy from the metallic particulate fuel, the power generation subsystem in fluid communication with the fuel storage subsystem; a bearer electrolyte for transporting the metallic particulate fuel through the particle regeneration subsystem, the fuel storage subsystem and the power generation subsystem; and a control unit configured to independently control flow of the bearer electrolyte between the particle regeneration subsystem and the fuel storage subsystem, and the fuel storage subsystem and the power generation subsystem.

Systems and methods for energy storage system are provided. The system includes a particle regeneration subsystem for applying electrical energy to regenerate metallic particulate fuel; a fuel storage subsystem for storing metallic particulate fuel, the fuel storage subsystem in fluid communication with the particle regeneration subsystem; and a power generation subsystem for producing electrical energy from the metallic particulate fuel, the power generation subsystem in fluid communication with the fuel storage subsystem; a bearer electrolyte for transporting the metallic particulate fuel through the particle regeneration subsystem, the fuel storage subsystem and the power generation subsystem; and a control unit configured to independently control flow of the bearer electrolyte between the particle regeneration subsystem and the fuel storage subsystem, and the fuel storage subsystem and the power generation subsystem.