Fuel cell

Patent metadata

Field	Value
Publication number	US-10205178-B2
Application number	US-201615299467-A
Country	US
Kind code	B2
Filing date	Oct 21, 2016
Priority date	Oct 22, 2015
Publication date	Feb 12, 2019
Grant date	Feb 12, 2019

Abstract

A fuel cell includes a membrane electrode assembly having a substantially rectangular shape having a first side and a second side opposite to the first side in a side direction. The substantially rectangular shape includes a first portion and a second portion. The first portion is closer to the first side than to the second side in the side direction. At least one of a cathode electrode and an anode electrode has a smaller amount of cracks in an electrode catalyst layer in the first portion than in the second portion. A fuel gas outlet manifold and an oxidant gas inlet manifold are closer to the first side than to the second side in the side direction. A fuel gas inlet manifold and an oxidant gas outlet manifold are closer to the second side than to the first side in the side direction.

First claim

What is claimed is:

1. A fuel cell comprising:
a membrane electrode assembly having a rectangular shape and including a solid polymer electrolyte membrane, a cathode electrode disposed on one surface of the solid polymer electrolyte membrane, and an anode electrode disposed on the other surface of the solid polymer electrolyte membrane;
a separator stacked on the membrane electrode assembly;
a fuel gas channel through which a fuel gas flows along an electrode surface of the anode electrode;
an oxidant gas channel through which an oxidant gas flows along an electrode surface of the cathode electrode in a direction opposite to a direction in which the fuel gas flows through the fuel gas channel;
a fuel gas outlet manifold and an oxidant gas inlet manifold that are formed near one end of the rectangular shape in a longitudinal direction, the fuel gas outlet manifold discharging the fuel gas in a stacking direction in which the membrane electrode assembly and the separator are stacked, the oxidant gas inlet manifold supplying the oxidant gas in the stacking direction; and
a fuel gas inlet manifold and an oxidant gas outlet manifold that are formed near the other end of the rectangular shape in the longitudinal direction, the fuel gas inlet manifold supplying the fuel gas in the stacking direction, the oxidant gas outlet manifold discharging the oxidant gas in the stacking direction,
wherein, in at least one of the cathode electrode and the anode electrode, an amount of cracks in a portion of an electrode catalyst layer near the one end in the longitudinal direction is smaller than an amount of cracks in a portion of the electrode catalyst layer near the other end in the longitudinal direction, the portion of the electrode catalyst layer near the one end being defined as a first region extending from the one end to an imaginary line spaced from the one end by a first distance in the longitudinal direction, and the portion of the electrode catalyst layer near the other end being defined as a second region extending from the other end to the imaginary line spaced from the other end by a second distance in the longitudinal direction.

2. The fuel cell according to claim 1 ,
wherein the membrane electrode assembly is a resin-framed MEA including a resin frame member that surrounds an outer periphery of the solid polymer electrolyte membrane, and
wherein a shape of a corner of a portion of the membrane electrode assembly near the one end in the longitudinal direction differs from a shape of a corner of a portion of the membrane electrode assembly near the other end in the longitudinal direction, the corners being disposed on the resin frame member.

3. The fuel cell according to claim 1 , wherein the first distance is in a range of 0.02×L to 0.1×L from the one end, where L is a length of the electrode catalyst layer in the longitudinal direction.

4. The fuel cell according to claim 2 , comprising:
power generation cells each including a first separator, a first resin-framed MEA, a second separator, a second resin-framed MEA, and a third separator that are stacked,
wherein a coolant channel is formed between each pair of the power generation cells that are adjacent to each other, and
wherein the electrode catalyst layer is an electrode catalyst layer of the cathode electrode that faces the anode electrode that is closest to the coolant channel with the solid polymer electrolyte membrane therebetween.

5. A fuel cell comprising:
a membrane electrode assembly having a substantially rectangular shape having a first side and a second side opposite to the first side in a side direction, the substantially rectangular shape comprising:
a first portion which is closer to the first side than to the second side in the side direction; and
a second portion which is a remaining portion of the substantially rectangular shape which excludes the first portion,

the membrane electrode assembly comprising:
a solid polymer electrolyte membrane having a first surface and a second surface opposite to the first surface in a stacking direction;
a cathode electrode disposed on the first surface; and
an anode electrode disposed on the second surface, at least one of the cathode electrode and the anode electrode having a smaller amount of cracks in an electrode catalyst layer in the first portion than in the second portion, the first portion being defined as a first region extending from one end of the cathode electrode or the anode electrode to an imaginary line at a first distance from the one end in the side direction, the second portion being defined as a second region extending from another end of the cathode electrode or the anode electrode to the imaginary line at a second distance from the another end in the side direction;
a separator stacked on the membrane electrode assembly in the stacking direction;
a fuel gas channel which is provided on a side of the anode electrode and through which a fuel gas flows in a first flow direction from the second side to the first side along an electrode surface of the anode electrode;
an oxidant gas channel which is provided on a side of the cathode electrode and through which an oxidant gas flows in a second flow direction from the first side to the second side along an electrode surface of the cathode electrode;
a fuel gas outlet manifold connected to the fuel gas channel to discharge the fuel gas in the stacking direction;
an oxidant gas inlet manifold connected to the oxidant gas channel to supply the oxidant gas in the stacking direction, the fuel gas outlet manifold and the oxidant gas inlet manifold being closer to the first side than to the second side in the side direction;
a fuel gas inlet manifold connected to the fuel gas channel to supply the fuel gas in the stacking direction; and
an oxidant gas outlet manifold connected to the oxidant gas channel to discharge the oxidant gas in the stacking direction, the fuel gas inlet manifold and the oxidant gas outlet manifold being closer to the second side than to the first side in the side direction.

6. The fuel cell according to claim 5 ,
wherein the membrane electrode assembly further comprises a resin frame member that surrounds an outer periphery of the solid polymer electrolyte membrane to constitute a resin-framed membrane electrode assembly,
wherein the resin frame member has a first corner to which the first side of the membrane electrode assembly is attached and a second corner to which the second side of the membrane electrode assembly is attached, and
wherein a shape of the first corner is different from a shape of the second corner.

7. The fuel cell according to claim 5 , wherein the first distance is in a range of 0.02×L to 0.1×L from the one end, where L is a length of the electrode catalyst layer in the side direction.

8. The fuel cell according to claim 6 , comprising:
power generation cells each including a first separator, a first resin-framed membrane electrode assembly, a second separator, a second resin-framed membrane electrode assembly, and a third separator which are stacked in the stacking direction,
wherein a coolant channel is formed between each pair of the power generation cells that are adjacent to each other, and
wherein the electrode catalyst layer is in the cathode electrode that faces the anode electrode that is closest to the coolant channel with the solid polymer electrolyte membrane therebetween.

9. The fuel cell according to claim 1 , wherein an average length of a plurality of cracks in the portion of the electrode catalyst layer near the one end is smaller than an average length of a plurality of cracks in the portion of the electrode catalyst layer near the other end.

10. The

Assignees

• Honda Motor Co Ltd

Inventors

• Tanaka Yukihito
• Ohmori Suguru
• Terada Eri

Classifications

• H01M8/04201

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title

• H01M8/0258 Primary

  characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant · CPC title

• H01M8/04007

  related to heat exchange · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/0273

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