Power generating cell

Patent metadata

Field	Value
Publication number	US-2019198889-A1
Application number	US-201816232178-A
Country	US
Kind code	A1
Filing date	Dec 26, 2018
Priority date	Dec 27, 2017
Publication date	Jun 27, 2019
Grant date	—

Abstract

In a power generating cell, on a surface on a side opposite from an electrolyte membrane in an anode, there are provided an outer peripheral surface positioned on an outer peripheral portion of the anode, a central surface located more inwardly than an inner peripheral portion of a resin frame member, and a stepped portion connecting the outer peripheral surface and the central surface to each other. A height of the central surface from the electrolyte membrane is lower than that of the outer peripheral surface. A protruding end surface of an end linear protrusion is in contact with the central surface.

First claim

What is claimed is:

1 . A power generating cell comprising a membrane electrode assembly on which electrodes are provided on both sides of an electrolyte membrane, metal separators disposed on both sides of the membrane electrode assembly, and a resin frame member protruding outwardly from outer peripheral portions of the electrodes and surrounding the outer peripheral portions of the electrodes in a state of being sandwiched between the outer peripheral portion of one of the electrodes and the outer peripheral portion of another of the electrodes;
wherein reaction gas flow fields are formed therein having a plurality of linear protrusions extending from one end to another end of the metal separators, and a plurality of linear flow field grooves formed between the plurality of linear protrusions, and which are configured to allow reaction gases to flow along power generating surfaces thereof from the one end to the other end; and in the power generating cell, seals are provided to surround the reaction gas flow fields and are configured to prevent leakage of the reaction gases; wherein on a surface on an opposite side from the electrolyte membrane on one of the electrodes, there are provided: an outer peripheral surface positioned on an outer peripheral portion of the one of the electrodes; a central surface located more inwardly than an inner end of the resin frame member; and a stepped portion connecting the outer peripheral surface and the central surface to each other; wherein a height of the central surface from the electrolyte membrane is lower than that of the outer peripheral surface; and among the plurality of linear protrusions, a protruding end surface of an end linear protrusion, which is positioned at an end of the reaction gas flow field in the flow field widthwise direction, is in contact with the central surface.

2 . The power generating cell according to claim 1 , wherein the protruding end surface of the end linear protrusion is in contact with the central surface over an entire length of the end linear protrusion.

3 . The power generating cell according to claim 1 , wherein the protruding end surface of the end linear protrusion is positioned on or in vicinity of a boundary between the central surface and the stepped portion.

4 . The power generating cell according to claim 3 , wherein:
each of the linear flow field grooves extends in a wavy shape; a first side wall of the end linear protrusion near the linear flow field grooves extends in a wavy shape along the linear flow field grooves; and a second side wall of the end linear protrusion opposite from the linear flow field grooves extends in a straight line shape along the boundary.

5 . The power generating cell according to claim 1 , wherein, on at least one of the metal separators, a bypass stopping convex portion, which is configured to prevent bypassing of the reaction gas, is provided between the seal and the end linear protrusion, and is in contact with the outer peripheral surface.

6 . The power generating cell according to claim 1 , wherein the seals are bead seals which are formed in a bulging manner on the metal separators.

7 . The power generating cell according to claim 4 , wherein the end linear protrusion comprises:
a concave curved portion in which the first side wall is curved so as to be recessed with respect to the seal; and a convex curved portion in which the first side wall is curved in a projecting manner toward the seal.

8 . The power generating cell according to claim 7 , wherein:
on the metal separator facing toward the one of the electrodes, a bypass stopping convex portion, which is configured to prevent bypassing of the reaction gas, is provided between the seal and the end linear protrusion, and is in contact with the outer peripheral surface; the bypass stopping convex portion comprising: a first convex portion provided between the seal and the concave curved portion; and a second convex portion provided between the seal and the convex curved portion.

9 . The power generating cell according to claim 8 , wherein the first convex portion is connected to the seal.

10 . The power generating cell according to claim 8 , wherein the second convex portion is connected respectively to the seal and to the end linear protrusion.

11 . The power generating cell according to claim 8 , wherein an intermediate convex portion configured to support an outer peripheral portion of the membrane electrode assembly is provided between the first convex portion and the second convex portion.

Assignees

• Honda Motor Co Ltd

Inventors

• Nishida Yosuke

Classifications

• H01M8/0263

  having meandering or serpentine paths · CPC title

• H01M8/1007

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

• H01M8/0254

  corrugated or undulated · CPC title

• H01M8/1006

  Corrugated, curved or wave-shaped MEA · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title