Fuel cell stack seal structure and production method therefor

Patent metadata

Field	Value
Publication number	US-10615433-B2
Application number	US-201615780912-A
Country	US
Kind code	B2
Filing date	Sep 26, 2016
Priority date	Dec 18, 2015
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A fuel cell stack seal structure of a fuel cell stack, the fuel cell stack including a plurality of fuel cell single cells that are stacked, each of the fuel cell single cells including a membrane electrode assembly and a pair of separators holding the membrane electrode assembly between the pair of separators, includes inner peripheral sealing members and an outer peripheral sealing member at peripheral edges of a pair of separators, in which the inner peripheral sealing members close a gap between inner peripheral ribs that protrude at least towards a mutually facing sides of the pair of separators, and the outer peripheral sealing member that closes a gap between outer peripheral ribs that protrude at least towards the mutually facing sides of the pair of separators. The inner peripheral sealing members and the outer peripheral sealing member form a first closed space between the inner peripheral sealing members and the outer peripheral sealing member. The outer peripheral sealing member has a notch that communicates the first closed space with the outside.

First claim

The invention claimed is:

1. A fuel cell stack seal structure of a fuel cell stack, the fuel cell stack comprising a plurality of fuel cell single cells that are stacked, each of the fuel cell single cells comprising a membrane electrode assembly and a pair of separators holding the membrane electrode assembly between the pair of separators,
wherein at least one of the pair of separators comprises an inner peripheral rib that protrudes at least towards a mutually facing side of the pair of separators at a peripheral part of the separator, at least one of the pair of separators comprises an outer peripheral rib that protrudes at least towards a mutually facing side of the pair of separators at an outer side of the inner peripheral rib,
the fuel cell stack seal structure comprising:
inner peripheral sealing members that close a gap between inner peripheral ribs of the pair of separators of each of the fuel cell single cells; and
an outer peripheral sealing member that is disposed at an outer side of the inner peripheral sealing members to close a gap between outer peripheral ribs of the pair of separators,

wherein a first closed space is formed between the inner peripheral sealing members and the outer peripheral sealing member,
wherein the outer peripheral sealing member has a notch that communicates the first closed space with the outside to allow air to move between the first closed space and the outside, and
wherein the outer peripheral sealing member comprises a notch forming member at the notch.

2. The fuel cell stack seal structure according to claim 1 , wherein the outer peripheral rib comprises a portion at which a distance between the pair of separators is shorter than a distance between outer peripheral ends of the pair of separators.

3. The fuel cell stack seal structure according to claim 1 , wherein each of the pair of separators comprises the outer peripheral rib, the outer peripheral rib comprises a protruded face and a distance between the protruded face of a first of the pair of separators and the protruded face of a second of the pair of separators is uniform, and the outer peripheral rib forms a narrow path at which the distance between the pair of separators is shorter than the distance between the outer peripheral ends of the pair of separators.

4. The fuel cell stack seal structure according to claim 3 , wherein an inner peripheral end of the outer peripheral sealing member is disposed in the narrow path.

5. The fuel cell stack seal structure according to claim 4 , wherein the outer peripheral sealing member comprises inner-outer peripheral sealing members and an outer-outer peripheral sealing member,
the inner-outer peripheral sealing members are integrally disposed in the narrow path and at an outer side of the narrow path, and
the outer-outer peripheral sealing member is disposed at an outer side of the inner-outer peripheral sealing members.

6. The fuel cell stack seal structure according to claim 5 , wherein the inner-outer peripheral sealing members contain a thermoset resin, and the outer-outer peripheral sealing member contains a thermoplastic resin.

7. The fuel cell stack seal structure according to claim 2 , wherein each of the pair of separators comprises the outer peripheral rib, the outer peripheral rib comprises a protruded face and a distance between the protruded face of a first of the pair of separators and the protruded face of a second of the pair of separators is uniform, and the outer peripheral rib forms a narrow path at which the distance between the pair of separators is shorter than the distance between the outer peripheral ends of the pair of separators.

8. The fuel cell stack seal structure according to claim 1 , wherein the outer peripheral sealing member and/or the inner peripheral sealing members have an adhesive function.

9. The fuel cell stack seal structure according to claim 1 , wherein the outer peripheral sealing member and/or the inner peripheral sealing members are made of a filler.

10. The fuel cell stack seal structure according to claim 9 , wherein the filler is made of a resin material.

11. The fuel cell stack seal structure according to claim 1 , wherein the membrane electrode assembly comprises a frame, and the frame is held by the inner peripheral rib.

12. The fuel cell stack seal structure according to claim 1 , further comprising:
a second inner peripheral sealing member that closes a gap between peripheral edges of the fuel cell single cells: and
a second outer peripheral sealing member that is disposed at an outer side of the second inner peripheral sealing member to close the gap between the peripheral edges of the fuel cell single cells,
wherein a second closed space is formed between the second inner peripheral sealing member and the second outer peripheral sealing member, and
the second outer peripheral sealing member has a notch that communicates the second closed space with the outside.

13. The fuel cell stack seal structure according to claim 1 , wherein the fuel cell stack comprises a plurality of fuel cell modules that are stacked, each of the modules comprising the plurality of fuel cell single cells that are stacked.

14. The fuel cell stack seal structure according to claim 13 , further comprising:
a sealing plate disposed between the fuel cell modules;
a third inner peripheral sealing member that closes a gap between a peripheral edge of an end separator of each of the fuel cell modules and a peripheral edge of the sealing plate; and
a third outer peripheral sealing member that is disposed at an outer side of the third inner peripheral sealing member to close the gap between the peripheral edge of the end separator of each of the fuel cell modules and the peripheral edge of the sealing plate,
wherein a third closed space is formed between the third inner peripheral sealing member and the third outer peripheral sealing member, and
the third outer peripheral sealing member has a notch that communicates the third closed space with the outside.

15. The fuel cell stack seal structure according to claim 1 ,
wherein at least one of the pair of separators comprises a protruded measuring terminal that extends in an in-plane direction of the separators, and
the measuring terminal is exposed at the notch.

16. A fuel cell stack seal structure of a fuel cell stack, the fuel cell stack comprising a plurality of fuel cell single cells that are stacked, each of the fuel cell single cells comprising a membrane electrode assembly and a pair of separators holding the membrane electrode assembly between the pair of separators,
wherein at least one of the pair of separators comprises an inner peripheral rib that protrudes at least towards a mutually facing side of the pair of separators at a peripheral part of the separator, at least one of the pair of separators comprises an outer peripheral rib that protrudes at least towards a mutually facing side of the pair of separators at an outer side of the inner peripheral rib,
the fuel cell stack seal structure comprising:
inner peripheral sealing members that close a gap between inner peripheral ribs of the pair of separators of each of the fuel cell single cells; and
an outer peripheral sealing member that is disposed at an outer side of the inner peripheral sealing members to close a gap between outer peripheral ribs of the pair of separators,

wherein a first closed space is formed between the inner peripheral sealing members and the outer peripheral sealing member,
wherein the outer peripheral sealing member has a notch that communicates the first closed space w

Assignees

• Nissan Motor

Inventors

• Sekine Norikatsu
• Numao Yasuhiro
• Ichihara Keiji
• Oku Takanori
• Miyaoka Hiroshi

Classifications

• H01M8/0286

  Processes for forming seals · CPC title

• H01M8/0276 Primary

  Sealing means characterised by their form (H01M8/0273 takes precedence) · CPC title

• H01M8/0254

  corrugated or undulated · CPC title

• H01M8/2465

  Details of groupings of fuel cells · CPC title

• H01M8/0271

  Sealing or supporting means around electrodes, matrices or membranes · CPC title