ELECTROCHEMICAL CELLS CONNECTED IN FLUID FLOW SERIES

• US 20100316935A1
• Filed: 12/04/2009
• Published: 12/16/2010
• Est. Priority Date: 12/05/2008
• Status: Abandoned Application

• Current Assignee: Fluidic, Inc.
• Original Assignee: Fluidic, Inc.
• Inventors: Trimble, Todd, Friesen, Cody A., Hayes, Joel R., Krishnan, Ramkumar
• Application Number:
  US12/631,484
• Publication Number:
  US 20100316935A1
• Time in Patent Office: Days
• US Class Current: 429/512
• CPC Class Codes: H01M 12/065 with plate-like electrodes or stacks of plate-like electrodes
• CPC Class Codes: H01M 50/70 Arrangements for stirring or circulating the electrolyte
• CPC Class Codes: H01M 50/77 with external circulating path
• CPC Class Codes: H01M 6/5077 Regeneration of reactants or electrolyte
• CPC Class Codes: H01M 8/04186 of liquid-charged or electrolyte-charged reactants
• CPC Class Codes: H01M 8/18 Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
• CPC Class Codes: H01M 8/22 Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen
• CPC Class Codes: H01M 8/225 Fuel cells in which the fuel is based on materials comprising particulate active material in the form of a suspension, a dispersion, a fluidised bed or a paste
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

An electrochemical cell system for generating electrical power is disclosed. The electrochemical cell system comprises a plurality of fluidly connected electrochemical cells. Each electrochemical cell comprises an anode and a cathode. The anode is configured to permit a fluid comprising at least an electrolyte to flow in contact therewith to oxidize a fuel. The cathode is permeable to an oxidizer and is configured to receive electrons to reduce the oxidizer. The cathode and the anode are spaced apart to define a gap therebetween for receiving the fluid flow. The plurality of electrochemical cells are connected in fluid flow series such that, for each pair of fluidly connected electrochemical cells, the fluid flows from a first cell of the pair of cells to a second cell of the pair of cells. The plurality of electrochemical cells are connected electrically in series such that, for each pair of fluidly connected electrochemical cells, the cathode of the first cell of the pair is electrically connected to the anode of the second cell of the pair.

Claims

1. An electrochemical cell system for generating electrical power, the electrochemical cell system comprising:

a plurality of fluidly connected electrochemical cells, each electrochemical cell comprising;

an anode configured to permit a fluid comprising at least an electrolyte to flow in contact therewith to oxidize a fuel; and

a cathode permeable to an oxidizer, the cathode being configured to receive electrons to reduce the oxidizer;

the cathode and the anode being spaced apart to define a gap therebetween for receiving the fluid flow;

wherein the plurality of electrochemical cells are connected in fluid flow series such that, for each pair of fluidly connected electrochemical cells, the fluid flows from a first cell of the pair of cells to a second cell of the pair of cells,

wherein the plurality of electrochemical cells are connected electrically in series such that, for each pair of fluidly connected electrochemical cells, the cathode of the first cell of the pair is electrically connected to the anode of the second cell of the pair, and

wherein an ionic resistance between the pair of fluidly connected electrochemical cells is greater than an ionic resistance within one electrochemical cell in the pair of cells.

2. The electrochemical cell system of claim 1, wherein the anode comprises a solid body of metal.

3. The electrochemical system of claim 2, wherein the metal is selected from the group consisting of zinc, iron, magnesium, aluminum, lithium, and any combination of two or more thereof.

4. The electrochemical cell system of claim 1, wherein the electrolyte comprises at least one aqueous solution selected from the group consisting of sulfuric acid, phosphoric acid, triflic acid, nitric acid, potassium hydroxide, sodium hydroxide, sodium chloride, potassium nitrate, lithium chloride, and any combination of two or more thereof.

5. The electrochemical cell system according to claim 4, wherein the electrolyte comprises potassium hydroxide.

6. The electrochemical cell system of claim 1, wherein the anode comprises a porous body configured to filter fuel particulates from the electrolyte for collecting the fuel thereon.

7. The electrochemical cell system of claim 6, wherein the fuel particulates include particulates selected from the group consisting of zinc, iron, magnesium, aluminum, lithium, and any combination of two or more thereof.

8. The electrochemical cell system of claim 1, wherein the cathode is a gas permeable electrode having an outer surface exposed to ambient air such that the oxidizer comprises oxygen that permeates the cathode.

9. The electrochemical cell system of claim 8, wherein the cathode comprises a barrier membrane on the outer surface thereof that is gas permeable and liquid impermeable so as to permit permeation of the oxidizer via the outer surface of the cathode and prevent the electrolyte from flowing through the outer surface of the cathode.

10. The electrochemical cell system of claim 1, wherein the cathode comprises a catalytic material selected from the group consisting of manganese oxide, nickel, cobalt, activated carbon, silver, platinum, and any combination of two or more thereof.

11. The electrochemical cell system of claim 1, further comprising a plurality of spacers, each of the spacers being disposed between the anode and the cathode of each of the plurality of electrochemical cells so as to space apart the anode and the cathode to create a gap through which the fluid containing the electrolyte flows.

12. The electrochemical system of claim 1, further comprising an anode holder configured to hold the anode of each of the plurality of electrochemical cells,

wherein the anode holder includes a plurality of inlets for introducing the fluid into the plurality of electrochemical cells, and a plurality of return ports to allow fluid introduced into each of the plurality of electrochemical cells to exit the plurality of electrochemical cells, wherein each inlet in the plurality of inlets and each return port in the plurality of return ports is associated with one electrochemical cell in the plurality of electrochemical cells.

13. The electrochemical system of claim 12, wherein the anode holder includes a plurality of recesses configured to receive the anode of each of the plurality of electrochemical cells, wherein each of the plurality of inlets and each of the plurality of return ports communicate with each of the plurality of recesses.

14. The electrochemical system of claim 13, wherein the anode holder further includes a plurality of passageways in communication with the plurality of return ports, the passageways being provided opposite the plurality of recesses, each passageway being associated with one electrochemical cell in the plurality of electrochemical cells.

15. The electrochemical system of claim 14, wherein, for each adjacent pair of electrochemical cells, a return channel in the first electrochemical cell of the pair is in communication with an inlet in the second electrochemical cell of the pair via a passageway in the second electrochemical cell of the pair.

16. The electrochemical cell system of claim 14, wherein the passageways have a tortuous, spiral or meandering configuration.

17. The electrochemical cell system of claim 14, wherein the passageways are longer than a gap between the anode and cathode.

18. The electrochemical cell system of claim 13, wherein each of the plurality of recesses has a conical shape for homogenizing a fluid flow throughout the anode in each of the plurality of electrochemical cells.

19. The electrochemical cell system of claim 1, further comprising a cathode holder configured to hold the cathode.

20. The electrochemical cell system of claim 1, further comprising one or more flow generators configured to generate the flow of fluid containing the electrolyte across the anode towards the cathode to transport oxidized fuel ions within the electrolyte away from the anode towards the cathode and to transport at least the electrolyte and by-products formed by reaction of the oxidized fuel ions and reduced oxidizer ions away from the gap.

21. The electrochemical cell system of claim 1, wherein the fluid flows from an anode of the first cell into the gap towards a cathode of the first cell and from the first cell to an anode of the second cell.

22. The electrochemical cell system of claim 1,

wherein the plurality of electrochemical cells are connected in fluid flow series such that, for each pair of fluidly connected electrochemical cells, the fluid flows from the gap in the first cell of the pair of cells towards a fluid channel formed between the pair of cells and from the fluid channel towards the gap in the second cell of the pair of cells.

23. The electrochemical system of claim 22, further comprising an anode holder configured to hold the anode of each of the plurality of electrochemical cells,

wherein the anode holder includes a fluid input port for introducing the fluid into the plurality of electrochemical cells, a fluid output port to allow the fluid to exit the plurality of electrochemical cells, and a plurality of return ports to allow fluid introduced into each of the plurality of electrochemical cells to exit each of the plurality of electrochemical cells and to enter the fluid channel between the pair of cells in the plurality of electrochemical cells.

24. The electrochemical system of claim 23, wherein the anode holder includes a plurality of cavities configured to receive the anode of each of the plurality of electrochemical cells, wherein each of the plurality of return ports communicates with each of the plurality of cavities.

25. The electrochemical system of claim 24, wherein the fluid channel formed between the pair of cells is in communication with a return port of one of the pair of cells.

26. The electrochemical cell system of claim 25, wherein the fluid channel runs along a length of a cavity between two adjacent cavities in the plurality of cavities.

27. The electrochemical cell system of claim 26, wherein the fluid channel is longer than the gap between the anode and cathode.

28. The electrochemical cell system of claim 23, further comprising a cathode holder configured to hold the cathode of each of the plurality of fluidly connected electrochemical cells.

29. An electrochemical cell system for generating electrical power, the electrochemical cell system comprising:

a plurality of fluidly connected electrochemical cells, each electrochemical cell comprising;

an anode configured to permit a fluid comprising at least an electrolyte to flow in contact therewith to oxidize a fuel; and

a cathode permeable to an oxidizer, the cathode being configured to receive electrons to reduce the oxidizer;

the cathode and the anode being spaced apart to define a gap therebetween for receiving the fluid flow;

wherein the plurality of electrochemical cells are connected in fluid flow series via a plurality of passageways such that, for each pair of fluidly connected electrochemical cells, the fluid flows from a first cell of the pair of cells to a second cell of the pair of cells through one passageway in the plurality of passageways,

wherein the plurality of electrochemical cells are connected electrically in series such that, for each pair of fluidly connected electrochemical cells, the cathode of the first cell of the pair is electrically connected to the anode of the second cell of the pair, and

wherein a length of the one passageway is greater than a minimum distance of the gap between the anode and the cathode.

30. The electrochemical cell of claim 29, wherein the length of the passageway is greater than ten times the dimension of the gap.

31. The electrochemical cell system of claim 29, wherein the anode comprises a solid body of metal.

32. The electrochemical system of claim 31, wherein the metal is selected from the group consisting of zinc, iron, magnesium, aluminum, lithium, and any combination of two or more thereof.

33. The electrochemical cell system of claim 29, wherein the electrolyte comprises at least one aqueous solution selected from the group consisting of sulfuric acid, phosphoric acid, triflic acid, nitric acid, potassium hydroxide, sodium hydroxide, sodium chloride, potassium nitrate, lithium chloride, and any combination of two or more thereof.

34. The electrochemical cell system according to claim 33, wherein the electrolyte comprises potassium hydroxide.

35. The electrochemical cell system of claim 29, wherein the anode comprises a porous body configured to filter fuel particulates from the electrolyte for collecting the fuel thereon.

36. The electrochemical cell system of claim 35, wherein the fuel particulates include particulates selected from the group consisting of zinc, iron, magnesium, aluminum, lithium, and any combination of two or more thereof.

37. The electrochemical cell system of claim 29, wherein the cathode is a gas permeable electrode having an outer surface exposed to ambient air such that the oxidizer comprises oxygen that permeates the cathode.

38. The electrochemical cell system of claim 37, wherein the cathode comprises a barrier membrane on the outer surface thereof that is gas permeable and liquid impermeable so as to permit permeation of the oxidizer via the outer surface of the cathode and prevent the electrolyte from flowing through the outer surface of the cathode.

39. The electrochemical cell system of claim 29, wherein the cathode comprises a catalytic material selected from the group consisting of manganese oxide, nickel, cobalt, activated carbon, silver, platinum, and any combination of two or more thereof.

40. The electrochemical cell system of claim 29, further comprising a plurality of spacers, each of the spacers being disposed between the anode and the cathode of each of the plurality of electrochemical cells so as to space apart the anode and the cathode to create a gap through which the fluid containing the electrolyte flows.

41. The electrochemical system of claim 29, further comprising an anode holder configured to hold the anode of each of the plurality of electrochemical cells,

wherein the anode holder includes a plurality of inlets for introducing the fluid into the plurality of electrochemical cells, and a plurality of return ports to allow fluid introduced into each of the plurality of electrochemical cells to exit the plurality of electrochemical cells, wherein each inlet in the plurality of inlets and each return port in the plurality of return ports is associated with one electrochemical cell in the plurality of electrochemical cells.

42. The electrochemical system of claim 41, wherein the anode holder includes a plurality of recesses configured to receive the anode of each of the plurality of electrochemical cells, wherein each of the plurality of inlets and each of the plurality of return ports communicate with each of the plurality of recesses.

43. The electrochemical system of claim 42, wherein the anode holder further includes the plurality of passageways, the plurality of passageways being in communication with the plurality of return ports, the passageways being provided opposite the plurality of recesses, each passageway being associated with one electrochemical cell in the plurality of electrochemical cells.

44. The electrochemical system of claim 43, wherein, for each adjacent pair of electrochemical cells, a return channel in the first electrochemical cell of the pair is in communication with an inlet in the second electrochemical cell of the pair via a passageway in the second electrochemical cell of the pair.

45. The electrochemical cell system of claim 42, wherein each of the plurality of recesses has a conical shape for homogenizing a fluid flow throughout the anode in each of the plurality of electrochemical cells.

46. The electrochemical cell system of claim 29, wherein the passageways have a tortuous, spiral or meandering configuration.

47. The electrochemical cell system of claim 29, further comprising a cathode holder configured to hold the cathode.

48. The electrochemical cell system of claim 29, further comprising one or more flow generators configured to generate the flow of fluid containing the electrolyte across the anode towards the cathode to transport oxidized fuel ions within the electrolyte away from the anode towards the cathode and to transport at least the electrolyte and by-products formed by reaction of the oxidized fuel ions and reduced oxidizer ions away from the gap.

49. The electrochemical cell system of claim 29, wherein the fluid flows from an anode of the first cell into the gap towards a cathode of the first cell and from the first cell to an anode of the second cell.

50. The electrochemical system of claim 29, further comprising an anode holder configured to hold the anode of each of the plurality of electrochemical cells,

wherein the anode holder includes a fluid input port for introducing the fluid into the plurality of electrochemical cells, a fluid output port to allow the fluid to exit the plurality of electrochemical cells, and a plurality of return ports to allow fluid introduced into each of the plurality of electrochemical cells to exit each of the plurality of electrochemical cells and to enter a passageway between the pair of cells in the plurality of electrochemical cells.

51. A method for generating electrical current using an electrochemical cell system comprising a plurality of electrochemical cells, the method comprising:

flowing a fluid comprising an electrolyte through the plurality of cells, each electrochemical cell in the plurality of cells comprising an anode and a cathode spaced apart by a gap, the gap being provided along the fluid flow path; and

inputting an oxidizer through the cathode of each electrochemical cell in the plurality of cells, the cathode being permeable to the oxidizer,

wherein in each electrochemical cell in the plurality of cells, fuel is oxidized at the anode and the oxidizer is reduced at the cathode, and a by-product is formed by reaction of the oxidized fuel and reduced oxidizer in the electrolyte.

52. The method of claim 51, wherein the flowing comprises flowing the fluid from the anode of each of the plurality of electrochemical cells towards the cathode of each of the plurality of cells to transport oxidized fuel ions within the electrolyte away from the anode towards the cathode and to transport at least the electrolyte and the by-products away from the gap.

53. The method of claim 51, wherein the flowing comprises, for each pair of fluidly connected electrochemical cells, flowing the fluid from one electrochemical cell in the pair of electrochemical cells to an anode of another electrochemical cell in the pair of electrochemical cells.

54. The method of claim 53, further comprising, for each pair of fluidly connected electrochemical cell, conducting electrical current in series from the cathode of the one electrochemical cell of the pair to the anode of the other electrochemical cell of the pair.

55. The method of claim 54, wherein the plurality of electrochemical cells include an anode terminal cell and a cathode terminal cell, the method further comprising connecting a load to the anode terminal cell and to the cathode terminal cell to permit a flow of electrons through the load.