Fuel cell stack structure

• US 20070134524A1
• Filed: 12/08/2006
• Published: 06/14/2007
• Est. Priority Date: 12/09/2005
• Status: Abandoned Application

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Lee, Jong-Hyun, Lim, Tae-Won, Yang, Yoo-Chang, Cho, Kyu-Taek
• Application Number:
  US11/636,699
• Publication Number:
  US 20070134524A1
• Time in Patent Office: Days
• US Class Current: 429/434
• CPC Class Codes: H01M 8/0247 characterised by the form characterised by a channel configuration H01M8/0258
• CPC Class Codes: H01M 8/0267 having heating or cooling means, e.g. heaters or coolant flow channels
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04201 Reactant storage and supply, e.g. means for feeding, pipes
• CPC Class Codes: H01M 8/2404 Processes or apparatus for grouping fuel cells
• CPC Class Codes: H01M 8/242 comprising framed electrodes or intermediary frame-like gaskets H01M8/2425, H01M8/244 take precedence
• CPC Class Codes: H01M 8/2465 Details of groupings of fuel cells
• CPC Class Codes: H01M 8/248 Means for compression of the fuel cell stacks
• CPC Class Codes: H01M 8/2483 characterised by internal manifolds
• CPC Class Codes: H01M 8/2484 characterised by external manifolds
• CPC Class Codes: H01M 8/249 comprising two or more groupings of fuel cells, e.g. modular assemblies
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fuel cell stack structure comprising a unit module, common distributor, and bus bar is disclosed. The unit module comprises fuel cells, current collecting plates, insulating plates, end plates, and fixing bands.

Claims

1. A fuel cell stack structure, comprising:

a plurality of unit modules comprising;

at least one fuel cell;

a current collecting plate pair, wherein each current collecting plate of said current collecting plate pair is respectively disposed at opposite sides of said fuel cell;

an insulating plate pair, wherein each insulating plate is respectively disposed at a distal side of each current collecting plate;

an end plate pair, wherein each end plate of said end plate pair is respectively disposed at a distal side of each insulating plate; and

fixing bands connecting said end plates;

a common distributor providing hydrogen, air, and coolant to said unit modules; and

a bus bar electrically connecting said unit modules.

2. The structure as defined in claim 1, wherein:

a first one of said end plate pair, a first one of said insulating plate pair, and a first one of said current collecting plate pair disposed at a first side of said unit module are formed at both ends thereof with communication holes; and

a second one of said end plate pair, a second one of said insulating plate pair, and a second one of said current collecting plate pair disposed at a second side of said unit module are formed without communication holes.

3. The structure as defined in claim 1, wherein each of said fixing bands comprises:

a pair of band heads enclosing an outer surface of said end plate and having a plurality of coupling holes; and

an insulator inserted into said coupling holes of said band heads and integrally formed with insulating bosses having bolt holes therein.

4. The structure as defined in claim 3, wherein:

said fixing band includes a band body connecting said band heads; and

said band heads and said band body are coated with an insulating material on outer surfaces thereof

5. The structure as defined in claim 2, wherein said first current collecting plate is integrally formed with a current outflow portion protruding from a side of said unit module perpendicular to said first side of said unit module.

6. The structure as defined in claim 1, wherein said bus bar has an elongated bar shape and includes:

a pair of bus bar heads disposed at both ends of said bus bar and bent in a first direction;

a bus bar body connecting said bus bar heads, wherein said bus bar body comprises a pair of separate parts coupled by connecting bolts and said bus bar body is coated with an insulating material; and

an insulating cover attached to said bus bar heads.

7. The structure as defined in claim 1, wherein at least one of said end plate pair comprises one of:

a first type of end plate formed with a plurality of bolt holes through which a plurality of module coupling bolts, having bolt heads, pass to couple with said common distributor wherein a plurality of bolt head covers are inserted into said first type of end plate thereby separating said bolt heads from said first type of end plate; and

a second type of end plate having a plurality of nuts to be coupled with said module coupling bolts wherein a plurality of nut covers are inserted into said second type of end plate thereby enclosing said nuts and separating a contact of said nuts and said end plate;

and wherein said first type of end plate of a first unit module faces said second type of end plate of a second unit module and said first type of end plate and said second type of end plate are coupled together by said module coupling bolts passing through said common distributor.

8. The structure as defined in claim 2, wherein a surface of said common distributor facing said first one of said end plate pair includes a plurality of gasket grooves into each one of which a gasket is inserted, said gasket grooves including a first subset nearer said module coupling bolts than a second subset, wherein said first subset of said gasket grooves is deeper than said second subset.

9. The structure as defined in claim 1, further comprising:

at least one first insulating layer having uneven portions on both upper and lower surfaces thereof for accommodating said fixing bands, said first insulating layer mounted between said unit modules;

at least one second insulating layer having uneven portions for accommodating said fixing bands on a lower surface thereof, said second insulating layer mounted on a farthest upper surface of said unit module stack; and

at least one third insulating layer having uneven portions for accommodating said fixing bands on an upper surface thereof, said third insulating layer mounted on a farthest lower surface of said unit module stack.

10. The structure as defined in claim 2, wherein an external side of said second one of said end plate paid opposite a connection between said unit module and said common distributor, is installed with an insulating cover.

11. The structure as defined in claim 1, said fuel cell comprising a membrane electrode assembly between separator plates;

said unit modules comprising;

12. The structure as defined in claim 1, wherein said at least one fuel cell comprising a plurality of fuel cells stacked in a row.

13. The structure as defined in claim 5, wherein said first insulating plate is substantially identical in shape to a body of said first current collecting plate not including said current outflow portion and said second insulating plate is substantially identical in shape to said second current collecting plate.

14. The structure as defined in claim 1, wherein each end plate is formed at an outer surface thereof with a plurality of reinforcing ribs.

15. A fuel cell stack structure, comprising:

a plurality of unit modules including fuel cells, each fuel cell comprising a membrane electrode assembly and separator plates;

said unit module comprising;

means for collecting current at both sides of said fuel cells;

means for insulating disposed outside of said means for collecting current;

means for stabilizing said unit module disposed outside of said means for insulating and having means for reinforcing an outer surface thereof; and

means for connecting said means for stabilizing;

means for providing hydrogen, air, and coolant to said unit modules; and

means for electrically connecting said unit modules.

16. A method of stacking fuels cells in a structure, comprising:

assembling a plurality of unit modules, comprising;

stacking fuel cells in a row;

collecting current with first plates on both sides of said row of fuel cells;

providing insulation with second plates on a side of said first plates facing away from said row of fuel cells; and

stabilizing said unit modules; and

providing hydrogen, air, and coolant to said unit modules; and

electrically connecting said unit modules.

17. The method of claim 16, further comprising electrically isolating said structure.

18. The method of claim 17, wherein electrically connecting said unit modules comprises:

fixing a first portion of a bus bar to a first unit module;

fixing a second portion of said bus bar to a second unit module; and

coupling said first and second portions of said bus bar body.

19. The method of claim 16, wherein providing hydrogen, air, and coolant to said unit modules comprises:

coupling one of said pair of end plates of each of a pair of unit modules with module coupling bolts passing through a common distributor of hydrogen, air, and coolant;

forming a passage for hydrogen, air, and coolant from said common distributor through said one of said pair of end plates on a first side of said row of fuels, a second plate on said first side of said row of fuels, and a first plate on said first side of said row of fuels to said fuel cells; and

forming a second passage returning to said common distributor from said row of fuel cells.

20. The method of claim 16, wherein stabilizing said unit modules providing a pair of end plates placed at a side of said second plates facing away from said row of fuel cells;

reinforcing said end plates; and

connecting said end plates.