JP2007194038A - Flow distribution plate for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flow distribution plate for a fuel cell advantageous to separate water present in a gas passage as apart as possible from a membrane electrode assembly, and to enhance exhausting ability of water in the gas passage. <P>SOLUTION: In the cross section along the vertical direction, at least a part of a gas passage 3A is equipped with a bottom wall surface 30 forming the bottom of the gas passage 3A of the flow distribution plate 2 arranged along the up and down direction, a ceiling wall surface 32 facing the bottom wall surface 30, and a standing wall surface 34 formed along the crossing direction to the bottom wall surface 30 and the ceiling wall surface 32 so as to face the membrane electrode assembly 1. The bottom wall surface 30 is descended and inclined toward the gravity direction (arrow G direction) with separation from the membrane electrode assembly 1 in the direction (arrow E direction) crossing to the vertical direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell distribution plate having a gas flow channel facing a membrane electrode assembly.

  Patent Document 1 discloses a fuel cell in which flow distribution plates called separators arranged in the vertical direction are stacked in the thickness direction. This flow distribution plate has a gas flow path facing the membrane electrode assembly. In a fuel cell, water is generated by a power generation reaction. In order to efficiently supply the reaction gas to the gas flow path of the flow distribution plate, it is preferable to efficiently drain water from the gas flow path of the flow distribution plate. When water as a liquid exists in the gas flow path of the flow distribution plate, the water is pushed out and discharged to the downstream side of the gas flow path of the flow distribution plate by the reaction gas flowing through the gas flow path.

  In Patent Document 1, as shown in FIG. 5, the flow distribution plate includes a gas flow path 3 </ b> X having a triangular shape in cross section. The gas flow path 3X includes a bottom wall surface 30X and a ceiling wall surface 32X. The back portion 36X of the gas flow path 3X is formed into an acute angle. Here, the bottom wall surface 30X of the gas flow path 3X is separated from the membrane electrode assembly 1X in the direction (arrow E direction) intersecting the vertical direction (arrow Y direction), that is, as it moves toward the arrow E1 direction, gravity is increased. Inclined downward in the direction (arrow G direction). As a result, the bottom wall surface 30X causes the water present in the gas flow path 3X to flow down in the direction of gravity (arrow G direction) along the bottom wall surface 30X of the gas flow path 3X, that is, along the arrow E1 direction. It is possible to move to the inner portion 36X of the gas flow path 3X as far as possible from the joined body 1X.

Furthermore, Patent Document 2 discloses a flow distribution plate in which an inclined surface is formed in a gas flow path. The inclined surface of the gas flow channel is inclined downward as it approaches the membrane electrode assembly.
JP-A-10-172585 JP 2005-108789 A

  According to the fuel cell according to Patent Document 1 described above, the gas flow path 3X has a triangular shape in cross section. For this reason, in the deep corner portion 36X of the gas flow path 3X, the influence of friction on the bottom wall surface 30X and the ceiling wall surface 32X increases, and the frictional resistance of the reaction gas increases. Therefore, in the acute-angled deep part 36X of the gas flow path 3X, the flow rate of the reaction gas is considerably higher due to frictional resistance than the opening 37X side of the gas flow path 3X (that is, the side facing the membrane electrode assembly 1X). May decrease. When the flow rate of the reaction gas is decreased, the ability to push water out of the gas flow path 3X downstream from the opening 36X side of the gas flow path 3X and to discharge the water may decrease. .

  Furthermore, since the back portion 36X of the gas flow path 3X has an acute angle shape in cross section, the surface tension increases in the back portion 36X. For this reason, the water present in the inner portion 36X is more easily affected by the surface tension or the like than the water present on the opening 37X side of the gas flow path 3X. Therefore, the water present in the acute-angled deep portion 36X of the gas flow path 3X is easily held at that position. As a result, even if the reaction gas flows into the gas flow path 3X, there is a possibility that water will not be pushed out toward the downstream side of the gas flow path 3X. For this reason, there is a limit in improving the water discharge performance in the gas flow path 3X of the flow distribution plate 2X.

  Furthermore, according to the flow distribution plate according to Patent Document 2, since the inclined surface of the gas flow path is inclined downward as it approaches the membrane electrode assembly, water present in the gas flow path is directed toward the membrane electrode assembly. Flow down. As a result, the area where water and the membrane electrode assembly come into contact increases. Therefore, the frequency of contact between the reaction gas and the membrane electrode assembly is reduced, and there is a limit to improving the reaction efficiency of the reaction gas.

  The present invention has been made in view of the above-described circumstances, and is advantageous in separating water existing in the gas flow path as far as possible from the membrane electrode assembly and improving the water discharge performance in the gas flow path of the flow distribution plate. An object of the present invention is to provide a fuel flow distributor plate.

The fuel cell distribution plate according to the present invention is disposed along the vertical direction, and has a facing surface facing the membrane electrode assembly of the fuel cell and a groove-shaped gas flow channel opening in the facing surface. In the flow distribution plate for use, in the cross-sectional view along the thickness direction and the vertical direction of the flow distribution plate, at least a part of the gas flow path forms a bottom wall surface that forms the bottom of the gas flow path of the flow distribution plate arranged along the vertical direction And a ceiling wall surface facing the bottom wall surface, and a standing wall surface formed along a direction intersecting the bottom wall surface and the ceiling wall surface so as to face the membrane electrode assembly,
The bottom wall surface is inclined downward in the direction of gravity as it is separated from the membrane electrode assembly in a direction intersecting the vertical direction.

  According to the present invention, as described above, the bottom wall surface of the gas flow path is inclined downward in the direction of gravity as the distance from the membrane electrode assembly increases. For this reason, even when water as a liquid is present in the gas flow path, the water can flow down in the direction of gravity along the bottom wall surface of the gas flow path. That is, water as a liquid can be separated from the membrane electrode assembly as much as possible. As a result, the area where the water as the liquid covers the membrane electrode assembly is reduced. Therefore, the contact probability between the reaction gas and the membrane electrode assembly is improved, and the reaction efficiency of the reaction gas is improved.

  According to the present invention, since the gas flow path includes the bottom wall surface and the ceiling wall surface, and also includes the standing wall surface, a clearance gap between the bottom wall surface and the ceiling wall surface can be secured at the back of the gas flow path. Therefore, it is possible to secure the flow path width at the back of the gas flow path. Therefore, the influence of the friction on the bottom wall surface and the ceiling wall surface, or the influence of the surface tension between the bottom wall surface and the ceiling wall surface, etc. is reduced in the inner part of the gas flow path. Therefore, it is difficult to hold water in the back of the gas flow path, and there is an advantage that water can easily flow toward the downstream side of the gas flow path.

  According to the present invention, since the gas flow path includes the bottom wall surface and the ceiling wall surface and the standing wall surface, a large flow path width at the back of the gas flow path can be ensured. For this reason, when water is present in the gas flow path, the water is caused to flow down in the direction of gravity along the bottom wall surface of the gas flow path, and is moved as far as possible from the membrane electrode assembly to the back of the gas flow path. Can do. For this reason, the contact probability between the reaction gas and the membrane electrode assembly is improved, and the reaction efficiency of the reaction gas is improved.

  Furthermore, according to the present invention, as described above, since the gas flow path includes the bottom wall surface and the ceiling wall surface and the standing wall surface, a large flow path width at the back of the gas flow path can be ensured. Therefore, the influence of friction on the bottom wall surface and the ceiling wall surface of the gas flow path, or the influence of surface tension or the like between the bottom wall surface and the ceiling wall surface is reduced. Therefore, it is difficult to hold water in the back of the gas flow path, and there is an advantage that water can easily flow toward the downstream side of the gas flow path. For this reason, it becomes advantageous to improve the discharge property of the water in the gas flow path of the flow distribution plate.

  The flow distribution plate is disposed along the vertical direction. Accordingly, the plurality of flow distribution plates are stacked along the lateral direction. The flow distribution plate has a facing surface facing the membrane electrode assembly of the fuel cell and a gas flow path opening in the facing surface. The material of the flow distribution plate may be carbon or metal.

  In the cross-sectional view along the thickness direction and the vertical direction of the flow distribution plate, at least a part of the gas flow path is formed on the bottom wall surface that forms the bottom of the gas flow path of the flow distribution plate arranged along the vertical direction. The ceiling wall surface which opposes, and the standing wall surface formed along the direction which cross | intersects with respect to a bottom wall surface and a ceiling wall surface so that a membrane electrode assembly may be faced. The bottom wall surface is inclined downward in the direction of gravity as it is separated from the membrane electrode assembly in a direction intersecting the vertical direction.

  According to the present invention, the form in which the ceiling wall surface is inclined downward in the direction of gravity as it is separated from the membrane electrode assembly in the direction intersecting the vertical direction is exemplified. In this case, it is advantageous for reducing the cross-sectional area of the gas flow path, and the flow velocity of the reaction gas flowing through the gas flow path is ensured. Here, as illustrated in FIG. 1, when the intersection angle between the facing surface and the bottom wall surface of the flow distribution plate is θ1, and when the intersection angle between the extension line of the facing surface of the flow distribution plate and the ceiling wall surface is θ2, θ1 is A configuration in which it is set larger than θ2 (θ1> θ2) is exemplified.

  According to the present invention, as illustrated in FIG. 1, among the channel widths of the gas channel, the channel width of the portion closest to the membrane electrode assembly is set to D1, and the most to the membrane electrode assembly. When the flow path width of a distant part is set to D2, the form which D1 is set larger than D2 (D1> D2) is illustrated. In this case, the reaction area is increased by increasing the contact area between the reaction gas flowing in the gas flow path and the membrane electrode assembly, while reducing the cross-sectional area of the gas flow path to increase the flow velocity of the reaction gas flowing through the gas flow path. This is advantageous for increasing the gas reaction probability.

  In addition, as a flow distribution plate used as the object of the present invention, a flow distribution plate for an oxidant electrode or a flow distribution plate for a fuel electrode may be used. However, since water is easily generated at the oxidant electrode due to the power generation reaction of the fuel cell, it is particularly effective for the flow distribution plate for the oxidant electrode.

  A first embodiment according to the present invention will be described below with reference to FIGS. As schematically shown in FIG. 1, a polymer fuel cell according to the present embodiment includes a membrane electrode assembly 1, a flow distribution plate 2 also called a separator that supplies an oxidant gas, and a separator that supplies a fuel gas. It is formed by laminating a flow distribution plate 2F also called a thickness direction. The membrane electrode assembly 1 includes a polymer solid electrolyte membrane 10 and a fuel electrode 11 (anode) and an oxidant electrode 12 (cathode) laminated in the thickness direction of the solid electrolyte membrane 10. The fuel electrode 11 is formed of a catalyst layer 11a facing the solid electrolyte membrane 10 and a gas diffusion layer 11b facing the flow distribution plate 2F. The oxidant electrode 12 is supplied with an oxidant gas (generally air), and is formed by a catalyst layer 12 a facing the solid electrolyte membrane 10 and a gas diffusion layer 12 b facing the flow distribution plate 2. Yes. The gas diffusion layers 11b and 12b are formed of aggregates such as carbon fibers so as to have gas permeability and conductivity. The fuel gas distribution plate 2 </ b> F has a gas flow path 300. The gas channel 300 includes a bottom wall surface 301 that forms the bottom of the gas channel 300, a ceiling wall surface 320 that faces the bottom wall surface 301, and a standing wall surface 340 that faces the fuel electrode 11 of the membrane electrode assembly 1. Yes.

  The flow distribution plate 2 is arranged vertically along with the flow distribution plate 2F in the vertical direction, and is formed of a carbon-based material or a metal having good corrosion resistance. As shown in FIG. 1, the flow distributor 2 includes a counter surface 20 facing the oxidant electrode 12 of the membrane electrode assembly 1 and a gas flow formed in a groove shape on the counter surface 20 so as to open to the counter surface 20. Road 3.

  FIG. 2 schematically shows a front view of the flow distributor 2. As shown in FIG. 2, the gas flow path 3 has an S shape or an inverted S shape from a supply hole 3i for supplying an oxidant gas as a reaction gas toward a discharge hole 3o for discharging an oxidant off gas. It is extended to. The oxidant gas supplied from the supply hole 3i flows along the gas flow path 3 toward the discharge hole 3o. Here, the gas flow path 3 has a gas flow path 3A flowing along the horizontal direction and a gas flow path 3C flowing along the vertical direction. Since the gas flow path 3C is along the vertical direction in the flow distribution plate 2, the water discharge property using gravity is ensured. Since the gas flow path 3A flows along the horizontal direction in the flow distribution plate 2, it is required to enhance the water discharge performance compared to the case of the gas flow path 3C.

  FIG. 1 shows a cross-sectional view taken along the thickness direction of the flow distribution plate 2 and along the vertical direction of the flow distribution plate 2. FIG. 1 is a cross-sectional view showing the thickness of the flow distribution plate 2 and the flow distribution plate 2F. FIG. 1 shows a cross-sectional view of the vicinity of the gas flow path 3 </ b> A through which the reaction gas flows in the lateral direction in the flow distribution plate 2. As shown in FIG. 1, the gas flow path 3 </ b> A through which the reaction gas flows laterally includes a bottom wall surface 30 that forms the bottom of the gas flow path 3 </ b> A of the flow distributor 2, a ceiling wall surface 32 that faces the bottom wall surface 30, and a membrane And an upstanding wall surface 34 facing the oxidant electrode 12 of the electrode assembly 1. As shown in FIG. 1, the gas flow path 3A has a non-triangular shape in cross section, and the bottom wall surface 30 and the ceiling wall surface 32 are in a non-parallel state. The standing wall surface 34 is formed along a direction intersecting the bottom wall surface 30 and the ceiling wall surface 32. In addition, although the standing wall surface 34 is along the opposing surface 20 of the flow distribution plate 2, and is made substantially parallel with respect to the opposing surface 20, it is not restricted to this.

  In FIG. 1, an arrow E direction indicates a direction orthogonal to the vertical direction (arrow Y direction). The bottom wall surface 30 of the gas flow path 3A is inclined downward toward the direction of gravity (arrow G direction) as the distance from the gas diffusion layer 12b of the oxidant electrode 12 of the membrane electrode assembly 1 increases, that is, toward the arrow E1 direction. is doing.

  For this reason, when water W as a liquid is present in the gas flow path 3A of the flow distribution plate 2, the water is distributed along the bottom wall surface 30 of the gas flow path 3A, that is, in the direction of arrow E1 (in the thickness direction of the flow distribution plate 2). It is possible to flow down in the direction of gravity (in the direction of arrow G) along the direction away from the opposing surface 20 of the plate 2. That is, it is advantageous to keep water away from the surface of the gas diffusion layer 12b of the oxidant electrode 12 of the membrane electrode assembly 1 as far as possible in the direction of the arrow E1. As a result, when water is present in the gas flow path 3A of the flow distribution plate 2, the area of the water covering the oxidant electrode 12 of the membrane electrode assembly 1 is reduced. Therefore, the contact probability between the oxidant gas, which is a reactive gas, and the oxidant electrode 12 of the membrane electrode assembly 1 is improved, the reaction efficiency of the oxidant gas is improved, and the power generation efficiency of the fuel cell is improved.

  According to the present embodiment, as shown in FIG. 1, the gas flow path 3A includes the bottom wall surface 30 and the ceiling wall surface 32, and also includes the standing wall surface 34. Therefore, the bottom wall surface 30 in the inner portion 36 of the gas flow path 3A. And the gap between the ceiling wall surface 32 can be increased. As a result, as shown in FIG. 1, the flow path width D <b> 2 of the back portion 36 of the gas flow path 3 </ b> A can be made larger than in the case of the related art 1 shown in FIG. 5. For this reason, in the back part 36 of 3 A of gas flow paths, the influence of the friction in the bottom wall surface 30 and the ceiling wall surface 32, surface tension, etc. can be made small. The reason is that the narrower the gap between the bottom wall 30 and the ceiling wall 32, the greater the influence of the friction of the fluid flowing therethrough and the influence of the surface tension, and the wider the gap between the bottom wall 30 and the ceiling wall 32. This is because the influence of the friction of the fluid flowing here and the influence of the surface tension are reduced.

  As described above, according to the present embodiment, the influence of friction, surface tension, and the like of the fluid flowing therethrough is reduced in the inner portion 36 of the gas flow path 3A. For this reason, it becomes easy for gas to flow also in the back portion 36 of the gas flow path 3A, and water is suppressed from being held in the back portion 36 due to surface tension. As a result, the advantage that water easily flows with the gas toward the downstream side of the gas flow path 3A can be obtained.

  By the way, the bottom wall surface 30 is inclined downward in the direction of gravity (arrow G direction) as it goes in the direction of arrow E1, and the ceiling wall surface 32 is directed in the opposite direction to the direction of gravity (arrow G direction) as it goes in the direction of arrow E1. It is also possible to use a channel structure that is inclined upward. In this case, the flow path cross-sectional area of the gas flow path 3A increases, and the flow rate of the reaction gas flowing through the gas flow path 3A decreases.

  In this respect, according to the present embodiment, as shown in FIG. 1, both the bottom wall surface 30 and the ceiling wall surface 32 are in the direction (arrow E direction) intersecting the vertical direction (arrow Y direction). As the distance from the oxidant electrode 12 increases, that is, as it goes in the direction of the arrow E1, it is inclined downward in the direction of gravity (the direction of the arrow G). For this reason, it is advantageous to reduce the flow path cross-sectional area of the gas flow path 3A and increase the flow rate of the reaction gas flowing through the gas flow path 3A. Here, as described above, when the flow rate of the reaction gas flowing through the gas flow path 3A is increased, it is advantageous to push the water remaining in the gas flow path 3A to the downstream side of the gas flow path 3A to be discharged.

  According to this embodiment, when the sectional view along the vertical direction (FIG. 1) is viewed, the intersection angle between the facing surface 20 of the flow distribution plate 2 and the bottom wall surface 30 is θ1, and the extension line of the counter surface 20 of the flow distribution plate 2 And θ1 is set to be larger than θ2 (θ1> θ2), where θ2 is the intersection angle between the ceiling wall surface 32 and the ceiling wall surface 32. Since such a structure is adopted, the flow passage cross-sectional area of the gas flow passage 3A can be reduced while flowing the water along the bottom wall surface 30 in the direction of gravity along the arrow E1 direction. This is advantageous for increasing the flow rate of the oxidizing gas which is the flowing reaction gas. In FIG. 1, θ1 and θ2 are acute angles of 90 degrees or less.

  Further, according to the present embodiment, among the channel widths of the gas channel 3A, the channel width of the portion of the opening 37 closest to the oxidant electrode 12 of the membrane electrode assembly 1 is D1, and the membrane electrode assembly When the flow path width of the farthest part of one oxidant electrode 12, that is, the depth 36 of the gas flow path 3A is D2, D1 is set to be larger than D2 (D1> D2). For this reason, while increasing the contact area between the oxidant gas (reactive gas) flowing through the gas flow path 3A and the oxidant electrode 12 of the membrane electrode assembly 1, the cross-sectional area of the gas flow path 3A is reduced to oxidize. It is advantageous to increase the flow rate of the agent gas.

  As an example of forming the gas flow path 3A of the separator 2, a press pressing die having a molding convex part for molding the gas flow path 3A is used, and the molding convex part for molding the gas flow path 3A is formed on the bottom wall surface 30. The gas flow path 3A can be formed by releasing the molds in parallel directions.

  FIG. 3 shows a second embodiment. The present embodiment basically has the same configuration and the same function and effect as the first embodiment. However, in addition to the flow distribution plate 2 for the oxidant electrode 12, the flow distribution plate 2F for the fuel electrode 11 is an object of the present invention. FIG. 3 shows a cross-sectional view along the thickness direction of the flow distribution plates 2 and 2F and along the vertical direction. As shown in FIG. 3, similarly to the first embodiment, the gas flow path 3 </ b> A of the flow distribution plate 2 includes a bottom wall surface 30, a ceiling wall surface 32 facing the bottom wall surface 30, and a standing wall surface 34.

  Hereinafter, a description will be given centering on differences from the first embodiment. In the flow distribution plate 2F for the fuel electrode 11, the gas flow path 3A includes a bottom wall surface 30 that forms the bottom of the gas flow path 3A of the flow distribution plate 2, a ceiling wall surface 32 that faces the bottom wall surface 30, and the membrane electrode assembly 1. And a standing wall 34 facing the fuel electrode 11. The standing wall surface 34 is formed along a direction intersecting the bottom wall surface 30 and the ceiling wall surface 32.

  Also in the present embodiment, when the sectional view along the vertical direction (FIG. 3) is viewed, the intersection angle between the facing surface 20 of the flow distribution plate 2F and the bottom wall surface 30 is θ1 ′, and the extension line of the facing surface 20 of the flow distribution plate 2F. And θ1 ′ is set to be larger than θ2 ′ (θ1 ′> θ2 ′).

  According to such a present Example, among the channel widths of the gas channel 3A, the channel width of the portion closest to the fuel electrode 11 of the membrane electrode assembly 1 is D1 ′, and the membrane electrode assembly 1 D1 ′ is set to be larger than D2 ′ (D1 ′> D2 ′), where D2 ′ is the farthest part of the fuel electrode 11, that is, the flow path width of the inner portion 36 of the gas flow path 3A. .

  In the present embodiment, similarly to the first embodiment, in the flow distribution plate 2F for the fuel electrode 11, even when water as a liquid is present in the gas flow path 3A, the water is supplied to the bottom of the gas flow path 3A. It can be made to flow down in the gravity direction (arrow G direction) along the wall surface 30, that is, along the arrow E2 direction. That is, water as a liquid can be separated from the gas diffusion layer 11 b of the fuel electrode 11 of the membrane electrode assembly 1 as much as possible. As a result, the contact probability between the fuel gas, which is the reaction gas, and the fuel electrode 11 of the membrane electrode assembly 1 is improved, the reaction efficiency of the fuel gas is improved, and the power generation efficiency is improved.

  Further, also in the flow distribution plate 2F, the gas flow path 3A includes the bottom wall surface 30 and the ceiling wall surface 32, and the standing wall surface 34. Therefore, the flow path width D2 'of the inner portion 36 of the gas flow path 3A can be secured. Therefore, the influence of friction on the bottom wall surface 30 and the ceiling wall surface 32 or the influence of surface tension between the bottom wall surface 30 and the ceiling wall surface 32 can be reduced in the inner portion 36 of the gas flow path 3A. Therefore, it is difficult for water to be held in the inner portion 36 of the gas flow path 3A, and there is an advantage that water can easily flow toward the downstream side of the gas flow path 3A.

  FIG. 4 shows a third embodiment. The present embodiment basically has the same configuration and the same function and effect as the first embodiment. FIG. 4 shows a cross-sectional view along the thickness direction of the flow distribution plates 2 and 2F and along the vertical direction. 3 A of gas flow paths face the bottom wall surface 30 which forms the bottom of the gas flow path 3A of the flow distribution board 2 arrange | positioned along an up-down direction, the ceiling wall surface 32 which opposes the bottom wall surface 30, and the membrane electrode assembly 1. Standing wall surface 34B. The standing wall surface 34 </ b> B is formed along a direction intersecting the bottom wall surface 30 and the ceiling wall surface 32, but has an arc concave shape in cross section so as to be recessed in a direction away from the membrane electrode assembly 1. If the arc is concave in the cross section, the corners in the cross section are reduced, so that the frictional resistance of water and reaction gas in the gas flow path 3A is further reduced.

  In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with appropriate modifications without departing from the scope of the invention. For example, the gas channel 3 </ b> A may be configured to extend along the oblique lateral direction so that the reactive gas flows in the lateral direction but flows upward or downward. The following idea can also be grasped from the above description.

(Additional Item 1) A fuel cell in which a membrane electrode assembly, a fuel flow distribution plate having a gas flow path, and an oxidant gas flow distribution plate having a gas flow path are stacked in the thickness direction. In the flow distribution plate and / or the fuel flow distribution plate, the flow distribution plate is a cross-sectional view along the thickness direction of the flow distribution plate and along the vertical direction, and at least a part of the gas flow path is disposed along the vertical direction. A bottom wall surface forming the bottom of the gas flow path, a ceiling wall surface facing the bottom wall surface, and a direction intersecting the bottom wall surface and the ceiling wall surface so as to face the membrane electrode assembly A fuel cell, wherein the bottom wall surface is inclined downward in the direction of gravity as it is separated from the membrane electrode assembly in a direction intersecting the vertical direction. .

  The present invention can be used in, for example, fuel cell systems for vehicles, stationary devices, electric devices, electronic devices, and portable devices.

FIG. 3 is a cross-sectional view of the main part of the fuel cell according to Example 1; It is a front view of a distribution board. FIG. 6 is a cross-sectional view of the main part of the fuel cell according to Example 2. FIG. 10 is a cross-sectional view of the main part of the fuel cell according to Example 3. It is sectional drawing of the principal part of a fuel cell concerning a prior art.

Explanation of symbols

  1 is a membrane electrode assembly, 2 is a flow distribution plate, 3 and 3A are gas flow paths, 30 is a bottom wall surface, 32 is a ceiling wall surface, and 34 is a standing wall surface.

Claims (5)

In the fuel cell distribution plate, which is disposed along the vertical direction and has a facing surface facing the membrane electrode assembly of the fuel cell and a groove-like gas flow channel opening in the facing surface,
In a sectional view along the thickness direction and the vertical direction of the flow distribution plate, at least a part of the gas flow path,
The bottom wall surface forming the bottom of the gas flow path of the flow distribution plate disposed along the vertical direction, the ceiling wall surface facing the bottom wall surface, the bottom wall surface and the membrane electrode assembly so as to face each other And a standing wall formed along a direction intersecting the ceiling wall,
The fuel cell distribution plate according to claim 1, wherein the bottom wall surface is inclined downward in the direction of gravity as it is separated from the membrane electrode assembly in a direction intersecting the vertical direction.   2. The fuel according to claim 1, wherein the ceiling wall surface is downwardly inclined toward the gravitational direction as the distance from the membrane electrode assembly is a cross-sectional view along the thickness direction and the vertical direction of the flow distribution plate. Battery distribution plate.   3. The cross-sectional view along the thickness direction and the vertical direction of the flow distribution plate according to claim 1 or 2, wherein an intersecting angle between the facing surface of the flow distribution plate and the bottom wall surface is θ1, and A fuel cell distribution plate, wherein θ1 is set to be larger than θ2 (θ1> θ2) when an intersection angle between the extension line and the ceiling wall surface is θ2.   The cross-sectional view along the vertical direction according to any one of claims 1 to 3, wherein the flow path width of the portion closest to the membrane electrode assembly is selected from the flow path widths of the gas flow paths. A fuel cell distribution plate, wherein D1 is set to be greater than D2 (D1> D2), where D1 is a flow path width of a portion farthest from the membrane electrode assembly.   5. The fuel cell flow distributor plate according to claim 1, wherein the fuel cell flow distributor plate is used for an oxidant electrode and / or a fuel electrode.

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