HYDROGEN PRODUCING FUEL FOR POWER GENERATOR

• US 20090113795A1
• Filed: 11/01/2007
• Published: 05/07/2009
• Est. Priority Date: 11/01/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Eickhoff, Steven J.
• Granted Patent: US 7,807,131 B2
• Time in Patent Office: Days
• US Class Current: 48/116
• CPC Class Codes: B01J 7/02 by wet methods
• CPC Class Codes: C01B 3/0005 Reversible uptake of hydrogen by an appropriate medium, i.e. based on physical or chemical sorption phenomena or on reversible chemical reactions, e.g. for hydrogen storage purposes purification of hydrogen C01B3/508; Reversible gettering of hydrogen; Reversible uptake of hydrogen by electrodes
• CPC Class Codes: C01B 3/0084 Solid storage mediums characterised by their shape, e.g. pellets, sintered shaped bodies, sheets, porous compacts, spongy metals, hollow particles, solids with cavities, layered solids
• CPC Class Codes: C01B 3/065 from a hydride
• CPC Class Codes: C01B 3/32 by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
• CPC Class Codes: C01B 3/323 Catalytic reaction of gaseous or liquid organic compounds other than hydrocarbons with gasifying agents
• CPC Class Codes: H01M 8/0247 characterised by the form characterised by a channel configuration H01M8/0258
• CPC Class Codes: H01M 8/025 semicylindrical
• CPC Class Codes: H01M 8/04216 characterised by the choice for a specific material, e.g. carbon, hydride, absorbent
• CPC Class Codes: H01M 8/0625 in a modular combined reactor/fuel cell structure
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• 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

Abstract

A hydrogen producing fuel comprises a chemical hydride and metal hydride. In one embodiment the chemical hydride evolves hydrogen spontaneously upon exposure to water vapor, and the metal hydride reversibly absorbs/desorbs hydrogen based on temperature and pressure. The hydrogen producing substance may be formed in the shape of a pellet and may be contained within a hydrogen and water vapor permeable, liquid water impermeable membrane.

Claims

1. A hydrogen producing substance comprising a chemical hydride and metal hydride.

2. The hydrogen producing substance of claim 1 wherein the chemical hydride evolves hydrogen spontaneously upon exposure to water vapor, and the metal hydride reversibly absorbs/desorbs hydrogen based on temperature and hydrogen pressure.

3. The hydrogen producing fuel of claim 2 wherein the chemical hydride is formed as a pellet having a hollow cylindrical shape and the metal hydride is concentric with and disposed within the hollow portion of the chemical hydride.

4. The hydrogen producing fuel of claim 3 and further comprising a heat conductor thermally coupled with the metal hydride.

5. The hydrogen producing fuel of claim 2 wherein the metal hydride is encapsulated within a porous silica or glass network.

6. The hydrogen producing fuel of claim 2 wherein the metal hydride is coated in copper.

7. The hydrogen producing fuel of claim 1 and further comprising a heat conductor disposed proximate the metal hydride.

8. The hydrogen producing fuel of claim 1 and further comprising a water vapor permeable, liquid water impermeable material formed about the chemical hydride.

9. The hydrogen producing substance of claim 1 wherein the chemical hydride is formed in a pellet shape, is porous and contains paths to allow water vapor to diffuse into the chemical hydride while still maintaining its shape.

10. The hydrogen producing substance of claim 9 wherein the pellet is cylindrical in shape and has a circumference and length suitable for inclusion in a power generator having the shape of a “

AA”

, “

AAA”

, “

C”

or “

D”

battery form factor.

11. A method of operating a hydrogen fuel cell based power generator, the method comprising:

producing hydrogen from a chemical hydride fuel in response to a demand for power;

desorbing hydrogen from a metal hydride fuel in response to a sustained pulse demand for power; and

adsorbing hydrogen to the metal hydride fuel with hydrogen from the chemical hydride fuel following the end of the sustained pulse demand for power.

12. A hydrogen producing fuel comprising a solid, water reactive fuel pellet form that is non-homogenous and is fissurized to allow water vapor to seep into the fissures.

13. The fuel of claim 12 and further comprising a water vapor permeable, liquid water impermeable material formed about the fuel pellet.

14. The fuel of claim 13 wherein the pellet has a circumference and combined length adapted for inclusion in a power generator having the shape of a “

AA”

, “

AAA”

, “

C”

or “

D”

battery form factor.

15. The fuel of claim 12 and further comprising a hydrophobic material dispersed around and in the fuel pellet.

16. The fuel pellet of claim 12 and further comprising a metal hydride material within the pellet.

17. A method comprising:

soaking a solid, water reactive, porous, hydrogen producing solid fuel pellet in a hydrophobic material to prevent rapid hydrogen release in the event of exposure of the fuel pellet to liquid water.

18. The method of claim 17 wherein the pellet is fissurized prior to soaking.

19. The method of claim 17 wherein the hydrophobic material comprises a petroleum based liquid.

20. The method of claim 17 wherein the hydrophobic material comprises a fluoropolymer dispersion.

21. A power generator comprising:

a container;

an ion exchange membrane within the container that produces water and energy from combining hydrogen with oxygen; and

a fissurized fuel pellet within the container, the fuel pellet having both a chemical hydride and a metal hydride that produce hydrogen when exposed to water vapor.

22. The power generator of claim 21 and further comprising a water vapor permeable, liquid water impermeable material formed about the fuel pellet.

23. The power generator of claim 21 and further comprising a valve separating the ion exchange membrane and the fuel pellet.

24. The power generator of claim 22 wherein the water vapor permeable, liquid water impermeable material comprises one or more layers of material comprising at least one of a fluoropolymer, polytetrafluoroethylene, oil or rubber.

25. The power generator of claim 24 and further comprising a hydrophobic material dispersed around and in the fuel pellet.

26. The power generator of claim 25 wherein the pellet is sufficiently fissurized to allow water vapor to seep into the fissures while still maintaining its shape.

27. The power generator of claim 24 wherein the pellet is of cylindrical shape.