Thermoelectric conversion of heat released during use of a power-plant or hydrogen storage material

• US 20050271916A1
• Filed: 06/06/2005
• Published: 12/08/2005
• Est. Priority Date: 06/07/2004
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Herbst, Jan F., Yang, Jihui, Verbrugge, Mark W.
• Granted Patent: US 7,405,013 B2
• Time in Patent Office: Days
• US Class Current: N/A
• CPC Class Codes: C01B 2203/066 with fuel cells
• 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: F17C 11/005 for hydrogen
• CPC Class Codes: H01M 16/003 of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2250/402 Combination of fuel cell with other electric generators
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04216 characterised by the choice for a specific material, e.g. carbon, hydride, absorbent
• CPC Class Codes: H01M 8/04701 Temperature
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: H10N 10/00 Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects integrated devices or assemblies of multiple devices H10N19/00
• CPC Class Codes: H10N 10/852 comprising tellurium, selenium or sulfur
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y10S 420/90 Hydrogen storage

Abstract

A method of generating electrical current in a system comprising a power-plant unit and/or hydrogen storage medium by transferring heat generated by the hydrogen storage medium and/or power-plant unit to a thermoelectric device, and converting the heat to generate electrical current using the thermoelectric device.

Claims

1. A hydrogen storage system, comprising:

a hydrogen storage medium that generates heat via an exothermic reaction; and

a thermoelectric device that is in heat exchange relationship with said hydrogen storage medium and that generates an electric current using said generated heat via said exothermic reaction.

2. The hydrogen storage system of claim 1, wherein said exothermic reaction is a hydrogen absorption reaction.

3. The hydrogen storage system of claim 1 wherein said hydrogen storage medium comprises a hydride.

4. The hydrogen storage system of claim 3 wherein said hydrogen storage medium comprises a hydride selected from the group consisting of LaNi₅H₇, Mg₂NiH₄, NaAlH₄, LiAlH₄, TiFeH₂, and VH₂, and mixtures thereof.

5. The hydrogen storage system of claim 1 wherein said thermoelectric device comprises a thermoelectric material.

6. The hydrogen storage system of claim 5 wherein said thermoelectric material comprises at least one material selected from the group consisting of a skutterudite, p-Te/Ag/Ge/Sb, Ce_yCo_xFe₄₋

xSb₁₂, Bi₂Te₃, SiGe, PbTe, BiSb, and mixtures thereof.

7. The hydrogen storage system of claim 1 wherein said thermoelectric device includes a thermoelectric material that has a peak energy conversion characteristic within a target temperature range.

8. The hydrogen storage system of claim 7 wherein said hydrogen storage medium is selected to generate sufficient heat during said exothermic reaction to achieve a temperature within said target temperature range at a high temperature side of said thermoelectric device.

9. A method of generating electrical current in a hydrogen storage system, comprising:

conducting an exothermic reaction in a hydrogen storage medium;

transferring heat generated by said exothermic reaction to a first side of a thermoelectric device; and

converting said heat to electrical current using said thermoelectric device.

10. The method of claim 9 further comprising selecting a material of said thermoelectric device based on thermal properties of said hydrogen storage medium.

11. The method of claim 9 wherein said hydrogen storage medium comprises a hydride.

12. The method of claim 11 wherein said hydrogen storage medium comprises a hydride selected from the group consisting of LaNi₅H₇, Mg₂NiH₄, NaAlH₄, LiAlH₄, TiFeH₂, and VH₂, and mixtures thereof.

13. The method of claim 9 wherein said thermoelectric device comprises a thermoelectric material.

14. The method of claim 13 wherein said thermoelectric material comprises at least one material selected from the group consisting of a skutterudite, p-Te/Ag/Ge/Sb, Ce_yCo_xFe₄₋

xSb₁₂, Bi₂Te₃, SiGe, PbTe, BiSb, and mixtures thereof.

15. The method of claim 9 wherein said thermoelectric device includes a thermoelectric material that has a peak energy conversion characteristic within a target temperature range.

16. The method of claim 15 further comprising selecting said hydrogen storage medium to generate sufficient heat during said exothermic reaction to achieve a temperature within said target temperature range at a high temperature side of said thermoelectric device.

17. A fuel cell system, comprising:

a fuel cell stack; and

a hydrogen storage system that supplies hydrogen to said fuel cell stack, comprising;

a hydrogen storage medium that generates heat via an exothermic reaction; and

a thermoelectric device that is in heat exchange relationship with said hydrogen storage medium and that generates an electric current using said heat generated by said exothermic reaction.

18. The fuel cell system of claim 17 wherein said hydrogen storage medium comprises a hydride.

19. The fuel cell system of claim 18 wherein said hydrogen storage medium comprises a hydride selected from the group consisting of LaNi₅H₇, Mg₂NiH₄, NaAlH₄, LiAlH₄, TiFeH₂, and VH₂, and mixtures thereof.

20. The fuel cell system of claim 17 wherein said thermoelectric device comprises a thermoelectric material.

21. The fuel cell system of claim 20 wherein said thermoelectric material comprises at least one material selected from the group consisting of a skutterudite, p-Te/Ag/Ge/Sb, Ce_yCo_xFe₄₋

xSb₁₂, Bi₂Te₃, SiGe, PbTe, BiSb, and mixtures thereof.

22. The fuel cell system of claim 17 wherein said thermoelectric device includes a thermoelectric material that has a peak energy conversion characteristic within a target temperature range.

23. The fuel cell system of claim 22 wherein said hydrogen storage medium is selected to generate sufficient heat during said exothermic reaction to achieve a temperature within said target temperature range at a high temperature side of said thermoelectric device.

24. The fuel cell system of claim 17 further comprising a thermal management system that provides a heat sink to a low temperature side of said thermoelectric device.

25. A fuel cell system, comprising:

a fuel cell stack; and

a hydrogen storage system that supplies hydrogen to said fuel cell stack, comprising;

a hydrogen storage medium; and

a thermoelectric device that is in heat exchange relationship with said hydrogen storage medium and that generates an electric current using heat generated by said hydrogen storage medium.

26. The fuel cell system of claim 25 wherein said heat is generated when said hydrogen storage medium absorbs hydrogen.

27. The fuel cell system of claim 25 wherein said heat is generated when said hydrogen storage medium desorbs hydrogen.

28. A system comprising a power-plant unit that produces effluent heat and a thermoelectric device that generates current using said effluent heat.

29. The system of claim 28 wherein said power-plant unit comprises a diesel engine and said effluent comprises diesel exhaust.

30. The system of claim 28 wherein said power-plant unit comprises a hydrogen storage medium and a diesel engine, and said effluent heat is derived from said medium and said engine.