Method and apparatus for facilitating a chemical reaction

• US 20040121196A1
• Filed: 12/18/2002
• Published: 06/24/2004
• Est. Priority Date: 12/18/2002
• Status: Active Grant

• Current Assignee: Intelligent Energy Limited (Lb-shell Plc)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Liu, Qin, Tsang, Joseph W., Mann, L. Chris
• Granted Patent: US 7,241,527 B2
• Time in Patent Office: Days
• US Class Current: 429/12
• CPC Class Codes: C01B 2203/066 with fuel cells
• CPC Class Codes: C01B 3/065 from a hydride
• CPC Class Codes: H01M 8/04216 characterised by the choice for a specific material, e.g. carbon, hydride, absorbent
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y10T 428/2938 Coating on discrete and individual rods, strands or filaments
• CPC Class Codes: Y10T 428/2991 Coated

Abstract

A method of facilitating a chemical reaction includes raising a temperature of a protective layer covering a catalyst in the presence of a chemical solution.

Claims

1. A method of facilitating a chemical reaction comprising raising a temperature of a protective layer covering a catalyst by activating a heating element to expose said catalyst to a chemical solution.

2. The method of claim 1, further comprising removing said protective layer by said raising of the temperature.

3. The method of claim 2, further comprising exposing said catalyst directly to said chemical solution by said removing of said protective layer.

4. The method of claim 3, wherein said chemical solution is an amino borane.

5. The method of claim 3, wherein said chemical solution is a metal borohydride.

6. The method of claim 5, wherein said metal borohydride comprises a gel.

7. The method of claim 5, wherein the metal borohydride is aqueous sodium borohydride.

8. The method of claim 7, further comprising generating hydrogen gas from said aqueous sodium borohydride exposed to said catalyst.

9. The method of claim 1, wherein said protective layer comprises wax, polymers, or copolymers of olefins.

10. The method of claim 1, further comprising compartmentalizing said chemical solution and providing a catalyst with a protective layer in each compartment.

11. The method of claim 10, further comprising selectively raising the temperature of individual compartments to remove said protective layers from said catalysts of selected compartments.

12. The method of claim 10, wherein each compartment of said chemical solution opens at an initiation point.

13. The method of claim 12, wherein said initiation point comprises a hydrophobic membrane.

14. The method of claim 12, wherein each of said compartments is predisposed to open at said initiation point upon an increase in pressure beyond ambient pressure, said increase in pressure resulting from exposure of said chemical solution to said catalyst.

15. A method of catalyzing a chemical solution comprising:

compartmentalizing said chemical solution into a plurality of cells, each of said plurality of cells comprising a catalyst covered by a protective layer and a heating element; and

selectively activating said heating elements to heat said protective layer covering said catalyst in one or more of said plurality of cells to remove said protective layer and expose said catalyst to said chemical solution.

16. The method of claim 15, further comprising generating hydrogen from said chemical solution at a controlled rate by said selective heating.

17. The method of claim 16, further comprising providing said hydrogen to a fuel cell.

18. The method of claim 15, wherein each of said plurality of cells opens at an initiation point.

19. The method of claim 18, wherein said initiation point comprises a hydrophobic membrane.

20. The method of claim 18, wherein each of said plurality of cells is predisposed to open at said initiation point upon an increase in pressure beyond ambient pressure, said increase in pressure resulting from exposure of said chemical solution to said catalyst.

21. The method of claim 15, wherein said chemical solution comprises a metal borohydride.

22. The method of claim 21, wherein said metal borohydride comprises a gel.

23. The method of claim 15, wherein said protective layer comprises wax, polymers, or copolymers of olefins.

24. A fuel pellet comprising:

a chemical solution;

a heating element; and

a chemical catalyst covered by a protective layer isolating said chemical catalyst from said chemical solution at ambient temperatures.

25. The pellet of claim 24, further comprising a plurality of compartmentalized fuel pellets, wherein each of said plurality of compartmentalized fuel pellets comprises a separate chemical solution, heating element, and chemical catalyst covered by a protective layer.

26. The pellet of claim 25, wherein each fuel pellet is independently operable by selectively activating said heating elements.

27. The pellet of claim 25, wherein said heating elements further comprise resistive heating elements.

28. The pellet of claim 25, wherein said chemical solution comprises a metal borohydride.

29. The pellet of claim 28, wherein said metal borohydride is a sodium borohydride solution.

30. The pellet of claim 25, wherein said protective coating comprises a heat-removable layer.

31. The pellet of claim 30, wherein said heat-removable layer comprises wax, polymers, or copolymers of olefins.

32. A method of generating hydrogen comprising:

providing a hydrogen-bearing fuel source in the presence of a catalyst with a protective coating insulating said catalyst from said fuel source;

selectively heating and removing said protective coating; and

exposing said catalyst to said hydrogen-bearing fuel source.

33. The method of claim 32 further comprising providing hydrogen gas produced from said hydrogen-bearing fuel source to a fuel cell.

34. The method of claim 32 wherein said hydrogen-bearing fuel source is compartmentalized into a plurality of compartments, and wherein each compartment comprises a catalyst with a protective coating and a separately controllable heating element.

35. A fuel cell cartridge comprising:

a hydrogen fuel source in the presence of a catalyst;

wherein said catalyst is insulated from said hydrogen fuel source by a heat-sensitive protective coating; and

a heating element for removing said heat-sensitive protective coating on demand.

36. The cartridge of claim 35, wherein said heating element is a resistive heating element.

37. The cartridge of claim 35, wherein said hydrogen fuel source is separated into a plurality of individual cells, each of said plurality of individual cells comprising a catalyst insulated from said hydrogen fuel source by a protective coating, and each of said plurality of individual cells comprising a heating element.

38. The cartridge of claim 37, wherein each of said plurality of individual cells comprises a cover layer with an initiator, said initiator predisposed to open at above-ambient temperatures or pressures to release hydrogen gas produced in said individual cells.

39. The cartridge of claim 35, wherein said hydrogen fuel source is an aqueous sodium borohydride solution.

40. The cartridge of claim 35, wherein said catalyst and said heat-sensitive protective coating are generally planar or spherical.

41. A fuel cell apparatus comprising:

an anode;

a cathode;

an electrolyte disposed between said anode and said cathode;

a hydrogen fuel source in the presence of a catalyst, said catalyst insulated from said hydrogen fuel source by a heat-sensitive protective coating; and

a heating element for removing said heat-sensitive protective coating on demand.

42. The apparatus of claim 41, wherein said heating element comprises a resistive heating element.

43. The apparatus of claim 41, wherein said hydrogen fuel source is divided into cells, and wherein each cell includes one or more of said heating element and said catalyst insulated by said protective coating.

44. An electronic device comprising:

a fuel cell;

a hydrogen generating system; and

an electrical load;

wherein said hydrogen generating system comprises a hydrogen-bearing chemical solution in the presence of a catalyst, said catalyst being insulated from said hydrogen-bearing chemical solution by a protective coating at ambient temperatures, and a heating element for removing said protective coating insulating said catalyst from said chemical solution.

45. The device of claim 44, wherein said hydrogen generating system further comprises a cover with an initiator predisposed to open at elevated temperatures or pressures to release hydrogen gas when said protective layer is removed from said catalyst.

46. The device of claim 44, further comprising a plurality of cells containing said chemical solution, wherein each of said plurality of cells includes one or more of said catalyst insulated by said protective coating and one or more of said heating element.

47. The device of claim 46, wherein each heating element of said plurality of cells is separately controllable.

48. A hydrogen generating apparatus comprising:

means for compartmentalizing a hydrogen-bearing fuel source;

means for catalyzing said hydrogen-bearing fuel source;

means for insulating said means for catalyzing from said hydrogen-bearing fuel source at ambient temperatures; and

means for removing said means for insulating.

49. The apparatus of claim 48, further comprising means for providing hydrogen produced from said hydrogen-bearing fuel source to a fuel cell.

50. The apparatus of claim 49, wherein said means for providing comprise a cover layer with an initiator, said initiator predisposed to open at above-ambient temperatures or pressures to release hydrogen gas produced in said means for compartmentalizing.

51. The apparatus of claim 48, wherein said means for removing comprises one or more thin film heating elements.

52. A method of making a chemical reactor comprising:

presenting an array of addressable heating elements to a substrate;

patterning a plurality of cell frames configured to receive a volume of chemical solution about said substrate; and

providing a catalyst insulated by a protective layer in each of said plurality of cell frames.

53. The method of claim 52, wherein said presenting further comprises placing resistors on said substrate.

54. The method of claim 52, wherein said presenting further comprises screen printed resistor elements.

55. The method of claim 52, wherein said presenting further comprises depositing and patterning resistor elements.

56. The method of claim 55, wherein said depositing and patterning further comprises sputtering, plating, CVD, PECVD, photomask/etch, or laser ablation.

57. The method of claim 52, wherein said array of addressable heating elements is addressed by direct drive or logic.

58. The method of claim 52, wherein said patterning further comprises patterning photosensitive materials or screen printing to form said plurality of cell frames.

59. The method of claim 52, wherein said patterning further comprises injection molding to form said plurality of cell frames.

60. The method of claim 59, wherein said plurality of cell frames are bonded to said substrate.

61. The method of claim 59, wherein said plurality of cell frames are integrally formed with said substrate.

62. The method of claim 52, further comprising enclosing said plurality of cell frames with a cover layer.

63. The method of claim 62, further comprising applying a second layer to said cover layer.

64. The method of claim 62, wherein said cover layer is integral to said plurality of cell frames.

65. A method of making a chemical reactor comprising:

embedding a heating element in a film;

constructing said film into a flexible bag; and

disposing a catalyst covered with a protective layer in said flexible bag.

66. The method of claim 65, wherein said disposing a catalyst covered with a protective layer further comprises coating said catalyst onto said film and coating said protective layer over said catalyst.

67. The method of claim 65, wherein said disposing a catalyst covered with a protective layer further comprises inserting a plurality of catalyst beads covered with said protective layer into said flexible bag.

68. The method of claim 65, wherein said protective layer is removable by the application of heat from said heating element.

69. The method of claim 65, further comprising inserting a hydrogen-bearing solution into said flexible bag.

70. A method of making a hydrogen generator comprising:

forming a plurality of individual cells;

providing a heating element to each of said plurality of individual cells;

coating a catalyst with a protective covering;

inserting said catalyst into each of said plurality of individual cells; and

enclosing each of said plurality of individual cells with a cover having one or more initiators.

71. The method of claim 70, further comprising filling each of said plurality of individual cells with a hydrogen-bearing chemical solution.

72. The method of claim 70, wherein said initiators comprise a hydrophobic membrane.