Power generating cell

Patent metadata

Field	Value
Publication number	US-2019198902-A1
Application number	US-201816229001-A
Country	US
Kind code	A1
Filing date	Dec 21, 2018
Priority date	Dec 26, 2017
Publication date	Jun 27, 2019
Grant date	—

Abstract

A power generating cell is equipped with an MEA to which a resin frame is attached, and a first metal separator. In the first metal separator, there are provided an oxygen-containing gas flow field through which an oxygen-containing gas flows along an electrode surface, an outer peripheral bead surrounding the oxygen-containing gas flow field and which prevents leakage of a reaction gas, and a plurality of first bypass stopping convex portions that prevent bypassing of the reaction gas. Intermediate convex portions that support the resin film are provided between mutually adjacent ones of the first bypass stopping convex portions.

First claim

What is claimed is:

1 . A power generating cell comprising a resin film equipped membrane electrode assembly, and metal separators disposed on both sides of the resin film equipped membrane electrode assembly, the resin film equipped membrane electrode assembly including a membrane electrode assembly formed with electrodes provided on both sides of an electrolyte membrane, and a resin film having a frame shape which is provided over an entire outer peripheral portion of the membrane electrode assembly, and reaction gas flow fields that allow reaction gases to flow along power generating surfaces being formed from one end to another end of the metal separators, and bead seals being provided that surround the reaction gas flow fields and configured to prevent leakage of the reaction gases, wherein the reaction gas flow fields include a plurality of flow field forming protrusions extending from the one end to the other end of the metal separators, and a plurality of flow field grooves formed between the plurality of flow field forming protrusions, and wherein a plurality of bypass stopping convex portions configured to prevent bypassing of the reaction gases are provided at intervals in a direction of extension of the flow field forming protrusions, between portions of the bead seals that extend from the one end to the other end of the metal separators, and the flow field forming protrusions that are positioned at ends in a flow field widthwise direction of the reaction gas flow fields;
wherein intermediate convex portions configured to support the resin film are provided in at least one of a pair of the metal separators, between mutually adjacent ones of the bypass stopping convex portions.

2 . The power generating cell according to claim 1 , wherein the intermediate convex portions are provided respectively in one of the metal separators and another of the metal separators.

3 . The power generating cell according to claim 2 , wherein the intermediate convex portions provided on the one of the metal separators face toward the intermediate convex portions provided on the other of the metal separators with the membrane electrode assembly intervening therebetween.

4 . The power generating cell according to claim 2 , wherein the intermediate convex portions differ in shape from each other between the pair of metal separators.

5 . The power generating cell according to claim 2 , wherein the intermediate convex portions provided on the one of the metal separators, and the intermediate convex portions provided on the other of the metal separators have shapes that extend along directions intersecting with each other.

6 . The power generating cell according to claim 2 , wherein:
the intermediate convex portions provided on the one of the metal separators extend along the flow field widthwise direction; and the intermediate convex portions provided on the other of the metal separators extend along the direction of extension of the flow field forming protrusions.

7 . The power generating cell according to claim 1 , wherein:
the bead seals are of a wavy shape in a plan view as viewed from a thickness direction of the metal separators; side walls of the bead seals facing toward the flow field forming protrusions positioned at the ends include concave side walls, which are curved so as to be recessed with respect to the flow field forming protrusions, and convex side walls, which are curved so as to bulge outwardly with respect to the flow field forming protrusions; the bypass stopping convex portions are disposed at positions adjacent to the concave side walls; and the intermediate convex portions are disposed at positions adjacent to the convex side walls.

8 . The power generating cell according to claim 7 , wherein the intermediate convex portions are placed adjacent to the convex side walls via gaps.

9 . The power generating cell according to claim 1 , wherein a plurality of the intermediate convex portions are disposed in parallel between mutually adjacent ones of the bypass stopping convex portions.

10 . The power generating cell according to claim 9 , wherein the plurality of intermediate convex portions differ in length from each other.

11 . The power generating cell according to claim 9 , wherein:
the plurality of bypass stopping convex portions are connected to the bead seal, and to the flow field forming protrusions positioned at the ends; and the plurality of intermediate convex portions are disposed at a distance from the plurality of bypass stopping convex portions, the bead seal, and the flow field forming protrusions positioned at the ends.

12 . The power generating cell according to claim 9 , wherein the plurality of intermediate convex portions are mutually of same length.

13 . The power generating cell according to claim 12 , wherein:
each of the plurality of bypass stopping convex portions includes, respectively, one bypass stopping convex portion one end of which is connected to the bead seal, and another end of which is separated from the flow field forming protrusions positioned at the ends, and another bypass stopping convex portion one end of which is connected to the bead seal, and another end of which is connected to the flow field forming protrusions positioned at the ends; and the one bypass stopping convex portion and the other bypass stopping convex portion are alternately arranged at intervals in the direction of extension of the flow field forming protrusions.

14 . The power generating cell according to claim 1 , wherein the intermediate convex portions have an arcuate curved shape when viewed from a thickness direction of the metal separators.

15 . The power generating cell according to claim 14 , wherein the intermediate convex portions are curved so as to have a convex shape on a side of the reaction gas flow field.

Assignees

• Honda Motor Co Ltd

Inventors

• Ishida Kentaro
• Tomana Yu
• Giga Akihito

Classifications

• H01M8/1007

  with both reactants being gaseous or vaporised (H01M8/12 takes precedence) · CPC title

• H01M8/0273

  with sealing or supporting means in the form of a frame · CPC title

• H01M2250/20

  Fuel cells in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M8/0263

  having meandering or serpentine paths · CPC title

• H01M8/0267

  having heating or cooling means, e.g. heaters or coolant flow channels · CPC title