Method and system for rebalancing electrolytes in a redox flow battery system
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.
1. A redox flow battery system, comprising:
a redox flow battery cell, and
a catalyst bed fluidly connected to the battery cell, wherein
the catalyst bed includes a substrate layer and a catalyst layer coated on a substrate layer spiral wound into a jelly roll structure.
2. The redox flow battery system of claim 1 , wherein the catalyst bed further includes a spacing layer positioned on the substrate layer spiral wound into the jelly roll structure, wherein the spacing layer separates successive catalyst and substrate layers within the jelly roll structure.
3. The redox flow battery system of claim 2 , wherein the catalyst layer comprises one or more of Pt, Pd, Ru or alloys thereof.
4. The redox flow battery system of claim 2 , wherein the substrate layer comprises carbon paper or carbon cloth.
5. The redox flow battery system of claim 2 , wherein the substrate layer comprises a membrane.
6. The redox flow battery system of claim 2 , wherein the spacing layer comprises a plastic mesh.
7. The redox flow battery system of claim 2 , further comprising a fluid recirculation device positioned between the redox flow battery cell and the catalyst bed, wherein the fluid recirculation device directs hydrogen gas from the battery cell to the catalyst bed, and the hydrogen gas is oxidized at the catalyst bed to form hydrogen ions.
8. The redox flow battery system of claim 7 , wherein the fluid recirculation device directs electrolyte including metal ions from the redox flow battery cell to the catalyst bed, and the metal ions are reduced at the catalyst bed.
9. The redox flow battery system of claim 8 , wherein the fluid recirculation device directs the hydrogen ions and the reduced metal ions from the catalyst bed to the redox flow battery cell.
10. The redox flow battery system of claim 9 , wherein the redox battery cell further comprises an electrolyte source, wherein the fluid recirculation device directs the hydrogen ions and the reduced metal ions from the catalyst bed to the electrolyte source before directing the hydrogen ions and the reduced metal ions from the catalyst bed to the redox flow battery cell.
11. A redox flow battery system, comprising:
a redox flow battery cell,
an electrolyte source supplying metal ions to the redox flow battery cell,
a catalyst bed, including a catalyst layer coated on a substrate layer spiral wound into a jelly roll structure,
a recirculation device fluidly connected between the redox flow battery cell and the catalyst bed, and
a controller, including executable instructions stored in memory to,
operate the recirculation device to direct hydrogen gas and metal ions from the redox flow battery cell to the catalyst bed.
12. The redox flow battery system of claim 11 , wherein
the hydrogen gas is oxidized at the catalyst layer to the hydrogen ions and the metal ions are reduced at the catalyst layer, and
the executable instructions further comprise operating the recirculation device to direct the hydrogen ions and the reduced metal ions from the catalyst layer to the electrolyte source.
13. The redox flow battery system of claim 12 , further comprising a hydrogen gas source external to the redox flow battery cell, wherein the executable instructions further comprise directing hydrogen gas from the hydrogen gas source to the catalyst bed.