Fluid regulating microvalve assembly for fluid consuming cells

• US 20060257701A1
• Filed: 10/25/2005
• Published: 11/16/2006
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Brooke Schumm III, Brooke Schumm Jr, Elizabeth Schumm, Kari J. Schumm
• Original Assignee: Eveready Battery Company Incorporated (Energizer Holdings, Inc.)
• Inventors: Schumm, Brooke Jr.
• Granted Patent: US 7,378,168 B2
• Time in Patent Office: Days
• US Class Current: N/A
• CPC Class Codes: H01M 12/06 with one metallic and one gaseous electrode
• CPC Class Codes: H01M 50/325 comprising deformable valve members, e.g. elastic or flexible valve members
• CPC Class Codes: H01M 50/609 Arrangements or processes for filling with liquid, e.g. electrolytes
• CPC Class Codes: H01M 50/627 Filling ports
• CPC Class Codes: H01M 8/04201 Reactant storage and supply, e.g. means for feeding, pipes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fluid regulating microvalve assembly for use to control fluid flow to a fluid consuming electrode, such as an oxygen reduction electrode, in an electrochemical cell. The microvalve assembly includes a stationary valve body having an aperture and a microactuator movable from a first position where the microvalve body aperture is closed to fluid flow to at least a second position where fluid is able to pass through the microvalve body aperture. The fluid regulating microvalve assembly can utilize cell potential or a separate source to open and close the microvalve. The fluid regulating microvalve assembly can be located outside the cell housing or inside the cell housing, for example between one or more fluid inlet apertures and the fluid consuming electrode. The invention includes a method of making a multilayer microvalve assembly, particularly one for use in a fluid depolarized battery, using a printing process to deposit at least one of the layers.

Claims

1. A microvalve assembly for an electrochemical cell, comprising:

a stationary microvalve body comprising a polymer, elastomer or rubber and an aperture located between a first surface and a second surface; and

a movable microactuator connected to the microvalve body and capable of moving between a first position where fluid cannot pass through the microvalve body aperture and a second position which allows fluid to pass through the microvalve body aperture, and wherein the microactuator is thermally actuated.

2. The microvalve assembly according to claim 1, wherein the microvalve body includes a substrate and at least one printed layer.

3. The microvalve assembly according to claim 2, wherein an insulating layer is printed on at least a portion of the substrate.

4. The microvalve assembly according to claim 3, wherein the insulating layer has a curved upper surface, and wherein a parting layer is present on the insulating layer curved upper surface.

5. The microvalve assembly according to claim 4, wherein the insulating layer of the microvalve body includes a boss deposited as a rim around the valve body aperture.

6. The microvalve assembly according to claim 1, wherein the microactuator comprises at least one printed layer.

7. The microvalve assembly according to claim 1, wherein the microactuator comprises a resistive material layer.

8. The microvalve assembly according to claim 7, wherein the resistive material layer comprises metal or a polymer containing conductive particles.

9. The microvalve assembly according to claim 1, wherein the microvalve assembly includes a segment of a circuit extending from a first lead located on the microvalve body to a resistive material layer of the movable microactuator to a second lead of the microvalve body.

10. The microvalve assembly according to claim 9, wherein the resistive material layer heats and distorts away from the microvalve body aperture to the second position when a potential is applied between the first lead and the second lead.

11. The microvalve assembly according to claim 1, wherein the microvalve assembly includes a latch operatively connected to the microvalve body.

12. The microvalve assembly according to claim 1, wherein the microvalve assembly includes an integrated control unit capable of controlling the movement of the microactuator between the first position and the second position.

13. The microvalve assembly according to claim 1, wherein the movable microactuator is operatively connected to the microvalve body through one or more printed supports, and wherein the movable microactuator comprises a membrane sheet and a resistive material layer printed on the membrane sheet.

14. The microvalve assembly according to claim 13, wherein the microactuator includes a boss connected to a bottom side of the membrane sheet that seals the microvalve body aperture in the first position to prevent fluid flow through the microvalve body aperture.

15. The microvalve assembly according to claim 13, wherein the movable microactuator includes a segment of a circuit extending from a first lead to the resistive material layer to a second lead, and wherein a potential applied between the first lead and the second lead causes distortion of the microactuator and movement from the first position to the second position.

16. An electrochemical cell, comprising:

a housing comprising one or more fluid inlet apertures, a negative electrode, a fluid consuming positive electrode, and a microvalve assembly operatively connected to the one or more fluid inlet apertures for controlling passage of fluid to the fluid consuming positive electrode, wherein the microvalve assembly comprises (a) a stationary microvalve body comprising a polymer, elastomer or rubber and an aperture located between a first surface and a second surface; and

(b) a movable microactuator connected to the microvalve body and capable of moving between a first position where fluid cannot pass through the microvalve body aperture and a second position which allows fluid to pass through the microvalve body aperture.

17. The electrochemical cell according to claim 16, wherein the microactuator moves away from the microvalve body in moving from the first to the second position, and the microactuator moves toward the microvalve body in moving from the second to the first position.

18. The electrochemical cell according to claim 16, wherein at least one of the microvalve body and the microactuator comprises a printed layer.

19. The electrochemical cell according to claim 16, wherein the fluid consuming positive electrode is an oxygen reduction electrode, and wherein the microactuator is thermally actuated.

20. The electrochemical cell according to claim 16, wherein the microvalve assembly includes a control unit that is adapted to monitor a fluid level within the housing and is able to apply a potential across the microvalve assembly.

21. The electrochemical cell according to claim 19, wherein the microvalve assembly is disposed within the cell housing or outside of the cell housing.

22. The electrochemical cell according to claim 21, wherein the cell can be disposed within an appliance on which the microvalve assembly is mounted.

23. The electrochemical cell according to claim 21, wherein the cell can be disposed within an appliance on which at least a portion of a control circuit for monitoring a fluid level within the cell housing and applying a potential across the microvalve assembly.

24. The electrochemical cell according to claim 21, wherein the cell is a sole power source of power to operate the microvalve assembly.

25. The electrochemical cell according to claim 16, wherein the microvalve assembly is operatively connected between the one or more fluid entry apertures and the fluid consuming positive electrode.

26. The electrochemical cell according to claim 16, wherein the cell is an air depolarized cell, an air-assisted cell, or a fuel cell.

27. The electrochemical cell according to claim 16, wherein the cell is a button cell, a cylindrical cell, or a prismatic cell.

28. The electrochemical cell according to claim 16, wherein the microvalve body includes a substrate and an insulating layer printed on at least a portion of the substrate.

29. The electrochemical cell according to claim 28, wherein the insulating layer has a curved upper surface, and wherein a parting layer is present on the insulating layer curved upper surface.

30. The electrochemical cell according to claim 29, wherein the insulating layer of the microvalve body includes a boss deposited as a rim around the valve body aperture.

31. The electrochemical cell according to claim 16, wherein the microactuator comprises a resistive material layer.

32. The electrochemical cell according to claim 31, wherein the resistive material layer comprises metal or a polymer containing conductive particles.

33. The electrochemical cell according to claim 16, wherein the microvalve assembly includes a segment of a circuit extending from a first lead located on the microvalve body to a resistive material layer of the movable microactuator to a second lead of the microvalve body.

34. The electrochemical cell according to claim 33, wherein the resistive material layer heats and distorts away from the microvalve body aperture to the second position when a potential is applied between the first lead and the second lead.

35. The electrochemical cell according to claim 16, wherein the microvalve assembly includes a latch operatively connected to the microvalve body.

36. The electrochemical cell according to claim 16, wherein the microvalve assembly includes an integrated control unit capable of controlling the movement of the microactuator between the first position and the second position.

37. The electrochemical cell according to claim 16, wherein the movable microactuator is operatively connected to the microvalve body through one or more printed supports, and wherein the movable microactuator comprises a membrane sheet and a resistive material layer printed on the membrane sheet.

38. The electrochemical cell according to claim 37, wherein the microactuator includes a boss connected to a bottom side of the membrane sheet that seals the microvalve body aperture in the first position to prevent fluid flow through the microvalve body aperture.

39. The electrochemical cell according to claim 37, wherein the movable microactuator includes a segment of a circuit extending from a first lead to the resistive material layer to a second lead, and wherein a potential applied between the first lead and the second lead causes distortion of the microactuator and movement from the first position to the second position.

40. A method for preparing a microvalve assembly, comprising the steps of:

forming a microvalve body having one or more layers;

forming a microactuator having one or more layers; and

operatively joining the microvalve body to the microactuator, wherein the microvalve body comprises an aperture that extends through the body from a first surface to a second surface, wherein the forming of the one or more microvalve body or microactuator layers, or both, includes utilizing a printing process, and wherein the microactuator is operatively connected to the microvalve body and capable of moving between a first position where fluid cannot pass through the microvalve body aperture and a second position which allows fluid to pass through the microvalve body aperture.

41. The method according to claim 40, wherein the microvalve assembly comprises a latch and a control unit, and at least one of the latch and the control unit comprises at least one material deposited by printing.

42. The method according to claim 40, wherein the microvalve body is formed by applying a conductive layer to a substrate, said conductive layer comprising first and second electrical leads.

43. The method according to claim 42, wherein an insulating layer is applied on at least a portion of the substrate and on at least a portion of the conductive layer.

44. The method according to claim 43, wherein material from the insulating layer is removed from over at least a portion of the conductive layer.

45. The method according to claim 44, wherein electrical contact is formed and is connected to the conductive layer, and wherein a parting layer is formed on at least a portion of the insulating layer.

46. The method according to claim 44, wherein a resistive layer is applied to the assembly and is in electrical contact with at least two electrical contacts, wherein a segment of a circuit is formed extending from the first lead to the resistive material to the second lead, and wherein upon application of a potential between the first lead and the second lead, the resistive material layer distorts away from the microvalve body aperture allowing fluid to flow therethrough.

47. The method according to claim 41, wherein the valve body is formed by printing at least one support on a substrate.

48. The method according to claim 41, wherein the microactuator is formed by printing at least one support to a membrane.

49. The method according to claim 48, wherein a resistive material layer is printed on the membrane.

50. The method according to claim 40, wherein the microvalve body and the microactuator are joined by lamination or an adhesive.

51. The method according to claim 49, wherein the microactuator includes a boss that seals the microvalve body aperture in the first position.

52. The method according to claim 47, wherein the microvalve body includes two printed end supports and a printed boss formed as a rim around the aperture in the substrate.

53. The method according to claim 40, wherein the microvalve body is formed having a latch.

54. The method according to claim 40, further including the step of connecting the microvalve assembly to a control unit.

55. The method according to claim 40, further including the step of assembling the microvalve assembly into an electrochemical cell.

56. The method according to claim 55, further including the step of positioning the microvalve assembly between a fluid inlet aperture of the cell and a fluid consuming electrode of the cell.