Redox and plating electrode systems for an all-iron hybrid flow battery

1. A system for a flow cell for a hybrid flow battery, comprising:

one or more electrolyte inlets;

one or more electrolyte outlets;

a redox plate, comprising:

a plurality of electrolyte flow channels;

conductive inserts attached to the redox plate between adjacent electrolyte flow channels; and

a redox electrode attached to a surface of the redox plate;

where the conductive inserts have a long edge parallel to a long edge of the electrolyte flow channels, the long edge of the conductive inserts extending along a first side of a polymeric 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 and displaced from the first planar surface in a first direction, the first direction being normal to the first and second planar surfaces and extending from the first planar surface toward the second planar surface;

a plurality of ridges intersecting the first and second planar surfaces such that the plurality of ridges divides the first planar surface into a first plurality of strips, and divides the second planar surface into a second plurality of strips;

a first plurality of flow channels adjacent to the first plurality of strips in the first direction; and

a second plurality of flow channels adjacent to the second plurality of strips in a second direction, the second direction being opposite the first direction; and

a membrane barrier located between the redox electrode and the plating electrode.

2. The system of claim 1 , wherein the electrolyte flow channels and conductive inserts form flow ribs that form a first edge of a first channel and a second edge of an adjacent second channel.

3. The system of claim 1 , wherein the plurality of folded fins comprises a plurality of perforations.

4. A system for an electrolyte flow plate for a hybrid flow battery, comprising:

a polymeric plate comprising a plurality of electrolyte flow channels; and

a plurality of conductive inserts attached to the polymeric plate between adjacent electrolyte flow channels;

where a length of the conductive inserts is greater than a width of the conductive inserts, the length extending along a first side of the polymeric plate;

wherein the electrolyte flow channels are voids comprising a long edge extending the length of the first side of the polymeric plate.

5. The system of claim 4 , wherein the conductive inserts comprise rectangular prisms having a long edge parallel to the long edge of the electrolyte flow channels, and extending the length of the first side of the polymeric plate.

6. The system of claim 5 , wherein the electrolyte flow channels and conductive inserts form flow ribs that form a first edge of a first channel and a second edge of an adjacent second channel.

7. The system of claim 6 , wherein the electrolyte flow channels are sloped from a base of the polymeric plate to a top face of the polymeric plate.

8. The system of claim 6 , wherein the electrolyte flow channels include two or more steps from a base of the polymeric plate to a top face of the polymeric plate.

9. The system of claim 4 , where the electrolyte flow channels are interdigitated or partially interdigitated.

10. The system of claim 4 , wherein the conductive inserts are Carbon/Graphite composite inserts.

11. A plating electrode for a battery, 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, and displaced from the first planar surface in a first direction, the first direction being normal to the first and second planar surfaces and extending from the first planar surface toward the second planar surface;

a plurality of ridges intersecting the first and second planar surfaces such that the plurality of ridges divides the first planar surface into a first plurality of strips, and divides the second planar surface into a second plurality of strips;

a first plurality of flow channels adjacent to the first plurality of strips in the first direction; and

a second plurality of flow channels adjacent to the second plurality of strips in a second direction, the second direction being opposite the first direction.

12. The plating electrode of claim 11 , where the plurality of ridges is perpendicular to the first and second planar surfaces.

13. The plating electrode of claim 12 , where the plurality of ridges includes a plurality of serrations.

14. The plating electrode of claim 11 , where the first plurality of strips has a first width, and the second plurality of strips has a second width, the second width being greater than the first width.

15. The plating electrode of claim 11 , where the plurality of folded fins comprises a plurality of perforations.

16. The plating electrode of claim 11 , where the first planar surface is coated with a non-conductive material.

17. The plating electrode of claim 11 , where the plurality of folded fins is fabricated from iron, an iron alloy, stainless steel, titanium, or carbon.

18. The plating electrode of claim 11 , further comprising:

a base plate coupled to the second planar surface such that the base plate, the plurality of ridges, and the first plurality of strips form a plurality of channels.

19. The plating electrode of claim 18 , further comprising:

one or more interdigitation or partial interdigitation plates, each interdigitation or partial interdigitation plate being perpendicular to the base plate and intersecting with a first end of the plurality of channels such that a flow of an electrolyte is restricted through the first end of the plurality of channels.