JP6180381B2 - Fuel cell stack - Google Patents

Description

  The present invention relates to a fuel cell stack having a fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and in which a plurality of the fuel cells are stacked.

  For example, in a polymer electrolyte fuel cell, an electrolyte membrane / electrode structure in which an anode electrode is disposed on one side of an electrolyte membrane made of a polymer ion exchange membrane and a cathode electrode is disposed on the other surface side ( MEA). The electrolyte membrane / electrode structure constitutes a power generation cell by being sandwiched between separators. A fuel cell is usually incorporated in a fuel cell vehicle as an in-vehicle fuel cell stack, for example, by stacking a predetermined number of power generation cells and disposing end plates at both ends in the stacking direction.

  In the fuel cell, a fuel gas channel for flowing fuel gas to the anode electrode and an oxidant gas channel for flowing oxidant gas to the cathode electrode are provided in the plane of the separator. On the other hand, between the separators adjacent to each other, a cooling medium flow path for flowing the cooling medium is provided along the surface direction of the separator.

  In the fuel cell, a so-called fuel gas communication hole through which fuel gas flows through the stacking direction, an oxidant gas communication hole through which oxidant gas flows, and a cooling medium communication hole through which a cooling medium flows are provided. Internal manifold type fuel cell is adopted. The fuel gas communication hole has a fuel gas inlet communication hole and a fuel gas outlet communication hole. The oxidant gas communication hole has an oxidant gas inlet communication hole and an oxidant gas outlet communication hole, and the cooling medium communication hole has a cooling medium inlet communication hole and a cooling medium outlet communication hole.

  In the fuel cell, at least one end plate is provided with a fluid manifold that supplies or discharges fluid (fuel gas, oxidant gas, or cooling medium) connected to each communication hole.

  At that time, since reaction product water, condensed water, and a cooling medium circulate in the fluid manifold, there is a possibility that a so-called liquid junction occurs in which this type of liquid water flows and current flows. For this reason, it is necessary to ensure the insulation of the whole fuel cell system. For example, a fuel cell stack disclosed in Patent Document 1 is known.

  In this fuel cell stack, a manifold member communicating with at least the reaction gas outlet communication hole is connected to the lower end portion in the stacking direction of the fuel cell stack. Further, at least a lower end portion of the discharge pipe that forms the reaction gas outlet communication hole is provided with a protruding portion that protrudes into the manifold member.

  Therefore, the dew condensation water that moves in the direction of gravity along the reaction gas outlet communication hole is disconnected from the continuity (liquid connection) under the action of the protruding portion and discharged into the manifold member. This makes it possible to prevent the occurrence of a liquid junction between the power generation cells as much as possible with a simple configuration.

JP 2011-204512 A

  The present invention has been made in connection with this type of technology, and with a simple configuration, it is possible to reliably suppress the connection of liquid water in the manifold member and prevent liquid junctions as much as possible. An object is to provide a fuel cell stack.

  A fuel cell stack according to the present invention includes a fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and a plurality of the fuel cells are stacked to form a stacking direction. End plates are disposed at both ends. The fuel cell stack includes a reaction gas channel that circulates the reaction gas along the electrode surface direction, a reaction gas inlet communication hole that communicates with the reaction gas channel, and that circulates the reaction gas in the stacking direction of the fuel cell. A gas outlet communication hole is provided.

  At least one of the end plates is provided with a manifold member in which a discharge port that communicates with the reaction gas outlet communication hole and discharges the reaction gas is disposed downward in the gravity direction. The manifold member is connected to a reaction gas discharge member that protrudes the discharge port to the inside, and the reaction gas discharge member has a flow that partially changes the flow direction of the reaction gas flowing downward from the discharge port in the gravity direction. A regulation section is provided.

  The flow restricting portion is connected to the flat portion disposed below the discharge port in the gravitational direction and the flat portion, and the reaction gas blown to the flat portion is directed from the upper side in the gravity direction to the central side of the reaction gas discharge member. And a folded-back portion that guides toward the vehicle.

  Further, in this fuel cell stack, the discharge port preferably has a circular shape of the opening cross section, and the flat portion is configured in a ring shape having an opening portion having an opening diameter smaller than the opening diameter of the discharge port. .

  Further, in this fuel cell stack, it is preferable that the discharge port has a circular shape of the opening cross section, and the flat portion has an opening having a rectangular shape of the opening cross section whose opening short side is shorter than the opening diameter of the discharge port. .

  According to the present invention, when the reaction gas is discharged into the reaction gas discharge member from the discharge port toward the lower side in the direction of gravity, a part of the reaction gas is sprayed on the flat portion constituting the flow restricting portion. For this reason, the flow direction of the reaction gas is partially changed from the lower side in the gravitational direction toward the upper side in the gravitational direction. Further, the reactive gas is guided from the upper side in the direction of gravity toward the center of the reactive gas discharge member along the folded portion provided to connect to the flat portion.

  Accordingly, since the reaction gas is folded back in a spiral shape by the flow restricting portion at a position spaced downward from the discharge port in the direction of gravity, liquid water that moves along the reaction gas flow flows from the discharge port to the inside of the reaction gas discharge member. It does not continue to the wall. Thereby, with a simple structure, the connection of the liquid water in a manifold member can be suppressed reliably, and a liquid junction can be prevented as much as possible.

FIG. 2 is a schematic perspective explanatory view from the first end plate side of the fuel cell stack according to the first embodiment of the present invention. It is a principal part disassembled perspective explanatory drawing of the fuel cell which comprises the said fuel cell stack. FIG. 3 is a cross-sectional view of the oxidant gas discharge manifold member and the oxidant gas discharge member taken along line III-III in FIG. 1. FIG. 4 is a cross-sectional explanatory view of the oxidant gas discharge manifold member and the oxidant gas discharge member. FIG. 5 is a cross-sectional view of the oxidant gas discharge member taken along line VV in FIG. 4. It is a principal part perspective explanatory view by the side of the 1st end plate of the fuel cell stack concerning a 2nd embodiment of the present invention. FIG. 7 is a cross-sectional view of the oxidant gas discharge manifold member and the oxidant gas discharge member taken along line VII-VII in FIG. 6. FIG. 8 is a cross-sectional view of the oxidant gas discharge member taken along line VIII-VIII in FIG. 7.

  As shown in FIG. 1, the fuel cell stack 10 according to the first embodiment of the present invention is mounted on, for example, a fuel cell electric vehicle (not shown). In the fuel cell stack 10, a plurality of fuel cells 12 are stacked in the horizontal direction (arrow B direction) with the electrode surface in an upright posture. Note that the fuel cell stack 10 may be configured by stacking a plurality of fuel cells 12 in the direction of gravity (arrow C direction).

  At one end in the stacking direction of the fuel cell 12, a first terminal plate 14a, a first insulating plate 16a, and a first end plate 18a are sequentially arranged outward. At the other end of the fuel cell 12 in the stacking direction, a second terminal plate 14b, a second insulating plate 16b, and a second end plate 18b are sequentially disposed outward.

  A first power output terminal 20a connected to the first terminal plate 14a extends outward from the central portion of the rectangular first end plate 18a. A second power output terminal 20b connected to the second terminal plate 14b extends outward from the center of the rectangular second end plate 18b.

  Between the sides of the first end plate 18a and the second end plate 18b, both ends of the connecting bar 22 are fixed by screws 24, and a plurality of stacked fuel cells 12 are subjected to a tightening load in the stacking direction (arrow B direction). Give.

  As shown in FIG. 2, the fuel cell 12 includes an electrolyte membrane / electrode structure 26, and a cathode side separator 28 and an anode side separator 30 that sandwich the electrolyte membrane / electrode structure 26.

  The cathode-side separator 28 and the anode-side separator 30 are made of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a metal plate whose surface is subjected to anticorrosion treatment. The cathode side separator 28 and the anode side separator 30 have a rectangular shape (rectangular shape or square shape) as a plane, and are formed into a concavo-convex shape by pressing a metal thin plate into a wave shape. For example, a carbon separator may be used as the cathode side separator 28 and the anode side separator 30 instead of the metal separator.

  An oxidant gas inlet communication hole 32a, a cooling medium inlet communication hole 34a, and a fuel gas outlet communication hole 36b communicate with each other in the arrow B direction at one edge of the long side direction (arrow A direction) of the fuel cell 12. Provided. The oxidant gas inlet communication hole 32a supplies an oxidant gas, for example, an oxygen-containing gas. The cooling medium inlet communication hole 34a supplies a cooling medium, and the fuel gas outlet communication hole 36b discharges a fuel gas, for example, a hydrogen-containing gas.

  A fuel gas inlet communication hole 36a, a cooling medium outlet communication hole 34b, and an oxidant gas outlet communication hole 32b are provided at the other edge of the fuel cell 12 in the long side direction so as to communicate with each other in the arrow B direction. The fuel gas inlet communication hole 36a supplies fuel gas, the cooling medium outlet communication hole 34b discharges the cooling medium, and the oxidant gas outlet communication hole 32b discharges the oxidant gas.

  The electrolyte membrane / electrode structure 26 includes, for example, a solid polymer electrolyte membrane 38 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode electrode 40 and an anode electrode 42 sandwiching the solid polymer electrolyte membrane 38. Prepare.

  The cathode electrode 40 and the anode electrode 42 have a gas diffusion layer (not shown) made of carbon paper or the like. Porous carbon particles having a platinum alloy supported on the surface are uniformly applied to the surface of the gas diffusion layer to form an electrode catalyst layer (not shown). The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 38.

  The surface 28a of the cathode-side separator 28 facing the electrolyte membrane / electrode structure 26 has an oxidant gas flow path that communicates an oxidant gas inlet communication hole 32a and an oxidant gas outlet communication hole (reaction gas outlet communication hole) 32b. 44 is formed. The oxidant gas channel 44 is formed by a plurality of wavy channel grooves (or linear channel grooves) extending in the direction of arrow A.

  A fuel gas flow path 46 that communicates the fuel gas inlet communication hole 36a and the fuel gas outlet communication hole (reactive gas outlet communication hole) 36b is formed on the surface 30a of the anode separator 30 facing the electrolyte membrane / electrode structure 26. Is done. The fuel gas channel 46 is formed by a plurality of wave-like channel grooves (or linear channel grooves) extending in the direction of arrow A.

  Between the surface 30b of the anode-side separator 30 and the surface 28b of the adjacent cathode-side separator 28, a cooling medium flow channel 48 that communicates with the cooling medium inlet communication hole 34a and the cooling medium outlet communication hole 34b is formed. The cooling medium flow path 48 extends in the horizontal direction and allows the cooling medium to flow over the electrode range of the electrolyte membrane / electrode structure 26.

  A first seal member 50 is integrally formed on the surfaces 28 a and 28 b of the cathode side separator 28 around the outer peripheral edge of the cathode side separator 28. A second seal member 52 is integrally formed on the surfaces 30 a and 30 b of the anode separator 30 so as to go around the outer peripheral edge of the anode separator 30.

  As the first seal member 50 and the second seal member 52, for example, EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber or the like, cushion material Alternatively, an elastic seal member such as a packing material is used.

  As shown in FIG. 1, the first end plate 18a includes an oxidant gas supply manifold member 54a, an oxidant gas discharge manifold member 54b, a fuel gas supply manifold member 56a, and a fuel gas discharge manifold member 56b. 58 is attached. The oxidant gas supply manifold member 54a communicates with the oxidant gas inlet communication hole 32a, and the oxidant gas discharge manifold member 54b communicates with the oxidant gas outlet communication hole 32b. The fuel gas supply manifold member 56a communicates with the fuel gas inlet communication hole 36a, and the fuel gas discharge manifold member 56b communicates with the fuel gas outlet communication hole 36b.

  Although not shown, the second end plate 18b includes a cooling medium supply manifold member that communicates with the cooling medium inlet communication hole 34a and a cooling medium discharge manifold member that communicates with the cooling medium outlet communication hole 34b. It is attached.

  As shown in FIGS. 1, 3, and 4, the oxidant gas discharge manifold member 54 b has a plate-like attachment portion 60. The plate-like attachment portion 60 is disposed corresponding to the oxidant gas outlet communication hole 32b of the first end plate 18a via a seal (not shown). The plate-like attachment portion 60 is fixed to the first end plate 18a by a plurality of screws 58.

  The manifold body 62 is integrally formed by bulging in the horizontal direction (arrow B direction) from the plate-like mounting portion 60. The manifold main body 62 has a hollow shape, and a discharge port 64 having a circular opening cross section for discharging the oxidant gas is provided at the tip of the manifold main body 62 with a tapered shape downward in the direction of gravity. . The manifold body 62 is provided with a disk-shaped connecting plate portion 66 in the vicinity of the discharge port 64, and the connecting plate portion 66 projects outward.

  An oxidant gas discharge member (reactive gas discharge member) 68 that projects a discharge port 64 to the inside is connected to the manifold main body 62. The oxidant gas discharge member 68 has a substantially cylindrical shape, and a connection plate portion 70 is integrally provided on the upper portion. The connecting plate portion 70 is fixed to the connecting plate portion 66 of the manifold main body portion 62 by screwing or the like, and the oxidant gas discharge member 68 is held by the manifold main body portion 62.

  A flow restricting portion 72 that changes the flow direction of the oxidant gas that flows downward from the discharge port 64 in the direction of gravity is provided below the oxidant gas discharge member 68. As shown in FIG. 4, the discharge port 64 and the flow restricting portion 72 are separated from each other in the gravitational direction by a predetermined distance L, and the oxidant gas discharge member 68 has a cylindrical shape over the distance L. Formed.

  As shown in FIGS. 3 and 4, the flow restricting portion 72 has a flat portion 74 that is disposed below the discharge port 64 in the gravity direction, and a folded portion 76. The folded portion 76 is connected to the flat portion 74 and guides the oxidant gas blown to the flat portion 74 from above in the direction of gravity toward the center of the oxidant gas discharge member 68.

  The folded portion 76 has a semicircular cross section, and is provided around the outer periphery of the disk-shaped flat portion 74. As shown in FIGS. 4 and 5, the flat portion 74 is configured in a ring shape having an opening 78 having an opening diameter D2 smaller than the opening diameter D1 of the discharge port 64. For example, a piping member 80 is connected to the lower end of the oxidant gas discharge member 68. Note that various devices such as an on-off valve and a back pressure valve can be connected to the lower end portion of the oxidant gas discharge member 68 instead of the piping member 80.

  The fuel gas discharge manifold member 56b connected to the fuel gas outlet communication hole 36b is configured in the same manner as the oxidant gas discharge manifold member 54b. For this reason, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  The operation of the fuel cell stack 10 configured as described above will be described below.

  First, as shown in FIG. 1, an oxidizing gas such as an oxygen-containing gas is supplied from the oxidizing gas supply manifold member 54a of the first end plate 18a to the oxidizing gas inlet communication hole 32a. Fuel gas such as hydrogen-containing gas is supplied from the fuel gas supply manifold member 56a of the first end plate 18a to the fuel gas inlet communication hole 36a.

  On the other hand, a coolant such as pure water, ethylene glycol, or oil is supplied from a coolant supply manifold member (not shown) of the second end plate 18b to the coolant supply passage 34a.

  As a result, as shown in FIG. 2, the oxidant gas is introduced from the oxidant gas inlet communication hole 32 a into the oxidant gas flow path 44 of the cathode-side separator 28. The oxidant gas moves in the direction of arrow A along the oxidant gas flow path 44 and is supplied to the cathode electrode 40 of the electrolyte membrane / electrode structure 26.

  On the other hand, the fuel gas is supplied from the fuel gas inlet communication hole 36 a to the fuel gas flow path 46 of the anode side separator 30. The fuel gas moves in the direction of arrow A along the fuel gas flow path 46 and is supplied to the anode electrode 42 of the electrolyte membrane / electrode structure 26.

  Therefore, in the electrolyte membrane / electrode structure 26, the oxidizing gas supplied to the cathode electrode 40 and the fuel gas supplied to the anode electrode 42 are consumed by an electrochemical reaction in the electrode catalyst layer to generate power. Done.

  Next, the oxidant gas consumed by being supplied to the cathode electrode 40 of the electrolyte membrane / electrode structure 26 circulates in the direction of arrow B along the oxidant gas outlet communication hole 32b, from the oxidant gas discharge manifold member 54b. It is discharged (see FIG. 1). On the other hand, the consumed fuel gas supplied to the anode electrode 42 of the electrolyte membrane / electrode structure 26 flows in the direction of arrow B along the fuel gas outlet communication hole 36b and is discharged from the fuel gas discharge manifold member 56b. .

  As shown in FIG. 2, the cooling medium supplied to the cooling medium inlet communication hole 34 a is introduced into the cooling medium flow path 48 between the cathode side separator 28 and the anode side separator 30. The cooling medium moves in the direction of arrow A to cool the electrolyte membrane / electrode structure 26, and then is discharged to the cooling medium outlet communication hole 34b. The cooling medium is discharged from the second end plate 18b.

  In this case, in the first embodiment, as shown in FIGS. 3 and 4, the first end plate 18a is provided with an oxidant gas discharge manifold member 54b communicating with the oxidant gas outlet communication hole 32b. . The oxidant gas discharge manifold member 54 b is connected with an oxidant gas discharge member 68 that projects the discharge port 64 to the inside, and a flow restricting portion 72 is provided below the oxidant gas discharge member 68. Yes.

  The flow restricting portion 72 has a flat portion 74 disposed below the discharge port 64 in the gravitational direction and a folded portion 76. The folded portion 76 is connected to the flat portion 74 and guides the oxidant gas blown to the flat portion 74 from above in the direction of gravity toward the center of the oxidant gas discharge member 68 (see FIG. 4). ).

  For this reason, part of the oxidant gas discharged into the oxidant gas discharge member 68 from the discharge port 64 downward in the gravitational direction is blown to the flat portion 74 constituting the flow restricting portion 72 from below in the gravitational direction. The flow direction is partially changed upward in the direction of gravity. Further, the oxidant gas is guided from the upper side in the direction of gravity toward the center of the oxidant gas discharge member 68 along the folded-back part 76 connected to the flat part 74.

  Accordingly, the oxidant gas is folded back in a spiral shape by the flow restricting portion 72 at a position spaced downward from the discharge port 64 in the direction of gravity. Thereby, the generated water (liquid water) moving along the oxidant gas flow does not continue from the discharge port 64 to the inner wall surface of the oxidant gas discharge member 68. For this reason, with a simple configuration, it is possible to reliably suppress the connection of the generated water in the oxidant gas discharge manifold member 54b and to prevent the liquid junction as much as possible.

  On the other hand, the fuel gas discharge manifold member 56b connected to the fuel gas outlet communication hole 36b is configured similarly to the oxidant gas discharge manifold member 54b. Therefore, with the simple configuration, it is possible to reliably suppress the connection of the condensed water (liquid water) in the fuel gas discharge manifold member 56b and prevent the liquid junction as much as possible.

  FIG. 6 is an explanatory perspective view of a main part on the first end plate 18a side constituting the fuel cell stack 90 according to the second embodiment of the present invention. The same components as those of the fuel cell stack 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIGS. 6 and 7, an oxidant gas discharge member 92 that protrudes the discharge port 64 to the inside is connected to the oxidant gas discharge manifold member 54b. The oxidant gas discharge member 92 has a substantially rectangular tube shape (substantially rectangular parallelepiped shape), and a flow restricting portion 94 that changes the flow direction of the oxidant gas flowing downward from the discharge port 64 in the gravity direction is provided at the lower part. It is done.

  As shown in FIGS. 7 and 8, the flow restricting portion 94 has a flat portion 96 disposed below the discharge port 64 in the gravitational direction and a folded portion 98. The folded portion 98 is connected to the flat portion 96 and guides the oxidant gas blown to the flat portion 96 from the upper side in the direction of gravity toward the center of the oxidant gas discharge member 92.

  The folded portion 98 has a semicircular cross section, and the flat portion 96 has an opening 100 having a rectangular opening cross section whose opening short side dimension H1 is shorter than the opening diameter D1 of the discharge port 64 (see FIG. 8). ). Although the opening long side of the opening part 100 is set to the dimension (or substantially the same dimension) smaller than the opening diameter D1 of the discharge port 64, it is not limited to this. As the shape of the opening 100, the wall surface forming the opening 100 only has to overlap with the discharge port 64. Although not shown, the fuel gas discharge manifold member can be configured in the same manner as the oxidant gas discharge manifold member 54b.

  In the second embodiment configured as described above, a part of the oxidant gas discharged into the oxidant gas discharge member 92 from the discharge port 64 downward in the gravitational direction is a flat surface constituting the flow restriction unit 94. The part 96 is sprayed. Therefore, a part of the oxidant gas can be folded back in a spiral shape by the flow restricting portion 94 at a position spaced downward from the discharge port 64 in the direction of gravity.

  Thereby, the generated water (liquid water) moving along the oxidant gas flow does not continue from the discharge port 64 to the inner wall surface of the oxidant gas discharge member 92. Therefore, with the simple configuration, the connection of the generated water in the oxidant gas discharge manifold member 54b can be reliably suppressed, and the liquid junction can be prevented as much as possible. The same effect can be obtained.

DESCRIPTION OF SYMBOLS 10, 90 ... Fuel cell stack 12 ... Fuel cell 18a, 18b ... End plate 26 ... Electrolyte membrane electrode assembly 28 ... Cathode side separator 30 ... Anode side separator 32a ... Oxidant gas inlet communication hole 32b ... Oxidant gas outlet communication Hole 34a ... Cooling medium inlet communication hole 34b ... Cooling medium outlet communication hole 36a ... Fuel gas inlet communication hole 36b ... Fuel gas outlet communication hole 38 ... Solid polymer electrolyte membrane 40 ... Cathode electrode 42 ... Anode electrode 44 ... Oxidant gas flow Path 46 ... Fuel gas flow path 48 ... Cooling medium flow path 54a ... Oxidant gas supply manifold 54b ... Oxidant gas discharge manifold 56a ... Fuel gas supply manifold 56b ... Fuel gas discharge manifold 60 ... Plate-like mounting part 62 ... Manifold body part 64 ... Exhaust port 66, 70 ... Connecting plate portion 68, 92 ... Oxidant gas exhaust Outlet member 72, 94 ... Flow restricting part 74, 96 ... Flat member 76, 98 ... Folded part 78, 100 ... Opening part

Claims (2)

A fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and a plurality of the fuel cells are stacked, and end plates are disposed at both ends in the stacking direction. And a reaction gas flow path for flowing the reaction gas along the electrode surface direction, a reaction gas inlet communication hole communicating with the reaction gas flow path, and for flowing the reaction gas in the stacking direction of the fuel cell, and a reaction gas outlet A fuel cell stack provided with a communication hole,
At least one of the end plates is provided with a manifold member in which a discharge port that communicates with the reaction gas outlet communication hole and discharges the reaction gas is disposed downward in the gravity direction,
The manifold member is connected to a reaction gas discharge member that protrudes the discharge port to the inside.
The reaction gas discharge member is provided with a flow restricting portion that partially changes the flow direction of the reaction gas flowing downward from the discharge port in the direction of gravity.
The flow restricting portion is a flat portion disposed below the discharge port in the gravity direction;
A folded portion that is connected to the flat portion and guides the reaction gas blown to the flat portion from above in the direction of gravity toward the center of the reaction gas discharge member;
I have a,
The discharge port has an opening cross-sectional circular shape,
Said flat portion, a fuel cell stack according to claim Rukoto configured in a ring shape having an opening portion of the small-diameter opening diameter than the opening diameter of the discharge port. A fuel cell in which an electrolyte membrane / electrode structure provided with a pair of electrodes on both sides of an electrolyte membrane and a separator are stacked, and a plurality of the fuel cells are stacked, and end plates are disposed at both ends in the stacking direction. And a reaction gas flow path for flowing the reaction gas along the electrode surface direction, a reaction gas inlet communication hole communicating with the reaction gas flow path, and for flowing the reaction gas in the stacking direction of the fuel cell, and a reaction gas outlet A fuel cell stack provided with a communication hole,
At least one of the end plates is provided with a manifold member in which a discharge port that communicates with the reaction gas outlet communication hole and discharges the reaction gas is disposed downward in the gravity direction,
The manifold member is connected to a reaction gas discharge member that protrudes the discharge port to the inside.
The reaction gas discharge member is provided with a flow restricting portion that partially changes the flow direction of the reaction gas flowing downward from the discharge port in the direction of gravity.
The flow restricting portion is a flat portion disposed below the discharge port in the gravity direction;
A folded portion that is connected to the flat portion and guides the reaction gas blown to the flat portion from above in the direction of gravity toward the center of the reaction gas discharge member;
Have
The discharge port has an opening cross-sectional circular shape,
The fuel cell stack, wherein the flat portion has an opening having a rectangular opening cross-section whose opening short side is shorter than the opening diameter of the discharge port.

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