JP2009252427A - Member for flow channel and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain degradation in power generating performance, caused by local detention of product water due to electrochemical reaction of reaction gas. <P>SOLUTION: In a cathode-side porous body flow channel 28, a cathode-side flow channel member 200 for guiding flow of oxidizing gas is arranged so as the oxidizing gas to flow from a site with slow flow speed of the oxidizing gas toward a site with quick flow speed. According to Bernoulli's theorem, the higher the flow speed of the site, the smaller the pressure generated by fluid becomes, so that, as shown in Fig.8, pressure P1 at a center part B becomes smaller than that P2 at an end part A, C. As a result, suction force F according to a pressure difference (P2-P1) acts from the end parts A and C toward the center part B, along the flowing direction of the oxidizing gas. Hence, product water Wa locally detained at the end parts A and C is suctioned to the center part B by the suction force F, and is drained outside the fuel cell, being forced to flow by the oxidizing gas which is flowing in the center part B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fuel cell, and more particularly to the structure of a channel member disposed in a gas channel of a fuel cell.

  A fuel cell has a stack structure in which a plurality of membrane electrode assemblies each having an anode electrode layer and a cathode electrode layer bonded to each other on both sides of an electrolyte membrane having proton conductivity with a separator interposed therebetween There is. In a fuel cell, for example, a porous member is disposed between a membrane electrode assembly and a separator in a reaction gas channel for supplying a reaction gas to each membrane electrode assembly. As the porous member, for example, expanded metal is used.

  In such a fuel cell, when a fuel gas (for example, hydrogen) and an oxidizing gas (for example, air) are supplied to the membrane electrode assembly from the outside through a manifold connected to the fuel cell, an electrochemical reaction occurs. In addition to generating electricity, water is generated by an electrochemical reaction. The generated water is flowed by the fuel gas and the oxidizing gas and drained to the outside of the fuel cell.

JP 2005-310633 A

  However, the flow rate of the reaction gas flowing through the reaction gas flow path varies depending on the overall configuration of the manifold and the fuel cell. If there is a variation in the flow rate of the reaction gas, the drainage efficiency of the produced water is reduced in the portion where the flow rate of the reaction gas is low compared to the portion where the flow rate is high. For this reason, between the membrane electrode assembly and the separator, the generated water stays in a portion where the flow rate of the reaction gas is low. As a result, the power generation performance of the fuel cell is reduced.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to suppress a decrease in power generation performance due to local retention of generated water by an electrochemical reaction of a reaction gas in a fuel cell.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
A flow path member disposed in a gas flow path for supplying a reaction gas used for power generation of a fuel cell to a membrane electrode assembly, formed by a porous body, and the reaction gas in the gas flow path A flow path member having a configuration for promoting movement of generated water generated by an electrochemical reaction of the fuel cell from a site where the flow velocity of the fuel cell is slow to a fast site.

  According to the flow path member of Application Example 1, in the gas flow path, the movement of the generated water is promoted from the part where the flow rate of the reaction gas is low to the part where it is fast. As a result, the generated water moved from the part where the flow rate of the reaction gas is low to the part where it is fast is drained outside the fuel cell by the reaction gas. Therefore, by applying the flow path member of Application Example 1 to the fuel cell, retention of generated water can be suppressed, and a decrease in power generation performance of the fuel cell can be suppressed.

  In the flow path member of Application Example 1, the configuration is configured such that the flow of the reaction gas in the gas flow path is directed from a slow part of the reaction gas flow to a fast part. According to the flow path member of Application Example 1, since the pressure due to the reaction gas is higher in the portion where the reaction gas flow rate is slower than the portion where the reaction gas flow rate is higher, A suction force corresponding to the pressure difference acts toward a site where the flow velocity of the reaction gas is slow. Therefore, the generated water can be moved to a part having a high flow rate, and the drainage of the generated water to the outside of the fuel cell can be promoted.

  In the flow path member of Application Example 1, the structure is arranged in the gas flow path at a portion where the flow rate of the reaction gas is high, and the flow of the reaction gas is guided in the same direction as the flow direction of the reaction gas. 1 porous body, and a second porous body that is disposed in a slow flow portion of the reactive gas in the gas flow path and guides the reactive gas flow toward the first porous body. Has been. According to the flow path member of Application Example 1, the flow path member is configured by a combination of the first porous body and the second porous body. Therefore, with a simple configuration, the flow direction of the reaction gas can be directed from the slow part to the fast part.

[Application Example 2]
A fuel cell having a stack structure in which a plurality of membrane electrode assemblies each having an electrode bonded to both surfaces of an electrolyte membrane are stacked with a separator interposed therebetween, and the fuel cell of Application Example 1 is interposed between the membrane electrode assembly and the separator. A fuel cell comprising a channel member. According to the fuel cell of Application Example 2, the generated water that partially retains due to the difference in the flow velocity of the reaction gas in the gas flow path surface is changed from the portion where the reaction gas flow velocity is low to the portion where the reaction gas flow velocity is high. Can be moved toward. Therefore, the water produced by the electrochemical reaction can be efficiently drained to the outside of the fuel cell, and the retention of the produced water can be suppressed. Therefore, it is possible to suppress a decrease in power generation performance of the fuel cell.

  In the present invention, the various aspects described above can be applied by appropriately combining or omitting some of them.

A. Example:
A1. Overall configuration of the fuel cell:
A schematic configuration of the fuel cell of the embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is an explanatory diagram illustrating a schematic configuration of a fuel cell 100 according to an embodiment. FIG. 2 shows a configuration of the fuel cell in the embodiment, and is a cross-sectional view cut along the AA cross section of FIG. In the embodiment, a solid polymer fuel cell that generates electric power by receiving supply of oxidizing gas and fuel gas will be described as an example. After that. Oxidizing gas and fuel gas are collectively referred to as reaction gas. As the fuel gas, for example, hydrogen gas is used, and as the oxidizing gas, for example, air is used.

  The fuel cell 100 is formed by alternately stacking power generators 20 and separators 40 and sandwiching them from both ends of the stacked body with terminals, insulators, and end plates (not shown).

  As shown in FIG. 2, the power generation body 20 includes an MEA 24 (Membrane Electrode Assembly), gas diffusion layers 23 a and 23 b, a cathode side porous body channel 28, and an anode side porous body channel 29. The gas diffusion layers 23 a and 23 b are disposed on both surfaces of the MEA 24. A member composed of the MEA 24, the gas diffusion layer 23a, and the gas diffusion layer 23b is referred to as MEGA 25.

  The MEA 24 includes a cathode electrode catalyst layer 22 a and an anode electrode catalyst layer 22 b on the surface of the electrolyte membrane 21. The electrolyte membrane 21 is a thin film of a solid polymer material that has proton conductivity and exhibits good electrical conductivity in a wet state, and is formed in a rectangle that is smaller than the outer shape of the separator 40 and larger than the outer shape of the gas channel. Yes. The electrolyte membrane 21 is, for example, Nafion. The cathode electrode catalyst layer 22a and the anode electrode catalyst layer 22b formed on the surface of the electrolyte membrane 21 carry a catalyst that promotes an electrochemical reaction, for example, platinum.

  The gas diffusion layers 23a and 23b are carbon porous bodies having a porosity of about 20%, and are formed of, for example, carbon cloth or carbon paper. The gas diffusion layers 23a and 23b are integrated with the MEA 24 by bonding to form the MEGA 25. The gas diffusion layer 23a is disposed on the cathode side of the MEA 24, and the gas diffusion layer 23b is disposed on the anode side. The gas diffusion layer 23a diffuses the oxidizing gas in the thickness direction and supplies the entire surface of the cathode electrode catalyst layer 22a. The gas diffusion layer 23b diffuses the fuel gas in the thickness direction and supplies it to the entire surface of the anode electrode catalyst layer 22b. The gas diffusion layers 23a and 23b have a relatively low porosity because the main purpose is gas diffusion in the thickness direction.

  The cathode-side porous body channel 28 is a channel for oxidizing gas that is used for an electrochemical reaction in the MEA 24. In the cathode side porous body channel 28, a cathode side channel member 200 for defining the flow direction of the oxidizing gas is disposed so as to be in contact with the MEGA 25 and the separator 40. The anode-side porous channel 29 is a fuel gas channel. An anode side flow path member 210 for defining the flow direction of the fuel gas is disposed in the anode side porous body flow path 29 so as to contact the MEGA 25 and the separator 40. Generally, the cathode side flow path member 200 and the anode side flow path member 210 can be formed of a gas permeable conductive member, for example, carbon paper, carbon cloth, carbon nanotube, or the like. In the embodiment, the cathode side flow path member 200 and the anode side flow path member 210 are regularly formed with through holes having the same shape in a metal plate. In the present embodiment, the cathode-side channel member 200 and the anode-side channel member 210 correspond to the “channel member” in the claims.

  The flow rate of the reaction gas flowing through the cathode side porous body channel 28 and the anode side porous body channel 29 varies depending on the overall configuration of the manifold and the fuel cell. The cathode-side channel member 200 is configured such that the oxidizing gas flowing in the cathode-side porous channel 28 flows from a part having a low flow rate toward a part having a low flow rate. Similar to the flow path member 200, the fuel gas flowing through the anode-side porous flow path 29 is configured to flow from a part having a low flow rate toward a part having a high flow rate. The configurations of the cathode-side channel member 200 and the anode-side channel member 210 will be described in detail later.

  The separator 40 is configured to form the wall surfaces of the cathode-side porous channel 28 and the anode-side porous channel 29. The separator 40 can be made of various materials such as a conductive member that does not allow reaction gas to pass through, for example, dense carbon, carbon that has been compressed by carbon, and baked carbon, or stainless steel. In the present embodiment, the separator 40 includes a cathode side plate 41 that contacts the cathode side porous body flow path 28, an anode side plate 43 that contacts the anode side porous body flow path 29, and an intermediate plate disposed therebetween. 42 is configured as a three-layer separator.

  The MEGA 25, the cathode side porous channel 28, and the anode side porous channel 29 are formed integrally with the seal gasket 26 so that the outer periphery is surrounded by the seal gasket 26. The seal gasket 26 is made of an insulating resin material made of rubber, such as silicon rubber, butyl rubber, and fluoro rubber, and has a seal line SL that suppresses leakage of fluid (hydrogen, oxidizing gas, cooling water) flowing in the manifold. Form. The separators 40 are disposed on both sides of the MEGA 25, the cathode-side porous channel 28, the anode-side porous channel 29, and the seal gasket 26 that are integrally formed.

  The flow of cooling water, fuel gas, and oxidizing gas will be described with reference to FIG. The cooling water flow path is configured such that the cooling water flows in this order via the cooling water supply manifold 11wm, the cooling water supply path 12w, and the cooling water discharge manifold 13wm. The fuel gas is configured such that the fuel gas flows in this order through the fuel gas supply manifold 11hm, the anode-side porous body flow passage 29, and the fuel gas discharge manifold 17hm. The oxidizing gas is configured such that air flows in this order through the oxidizing gas supply manifold 11am, the cathode-side porous body flow path 28, and the oxidizing gas discharge manifold 17am. Hereinafter, in the examples, the direction in which the reaction gas flows is referred to as the flow direction. In the embodiment, the flow direction of the oxidizing gas is downward → upward when the separator 40 is erected, and the flow direction of the fuel gas is horizontal (left and right) direction when the separator 40 is erected.

A2. About fuel cell drainage:
A2-1. About the mechanism of retention of generated water:
FIG. 3 is a schematic diagram illustrating a mechanism of retention of generated water of the fuel cell in the example. In FIG. 3, the cathode side porous body flow path 28 is shown as an example. Since the space between the MEGA 25 and the separator 40 is very narrow, the water produced by the electrochemical reaction of the fuel cell 100 is usually generated between the MEGA 25 and the separator 40 as shown in FIG. It is made to flow by the oxidizing gas flowing through the side porous body flow path 28 and is drained to the outside of the fuel cell through the manifold. However, depending on the overall structure of the fuel cell, such as the manifold structure and the stacking direction, the flow rate of the oxidizing gas flowing in the surface of the cathode side porous body flow path 28 may be partially different. May stay. For example, as shown in FIG. 3, the flow velocity of the central portion B of the cathode-side porous channel 28 corresponding to the central portion of the separator 40 is the end of the cathode-side porous channel 28 corresponding to the end of the separator 40. When the flow rate is faster than the flow rates of A and C, the generated water is drained to the outside of the fuel cell without staying in the central portion B, but only a part of the generated water is drained at the end portions A and C. Instead, the generated water Wa stays in proportion to the operation time of the fuel cell. The flow rate of the oxidizing gas is slower on the outlet side (in FIG. 3, above the cathode-side porous passage 28) than on the inlet side of the oxidizing gas (in FIG. 3, below the separator 40). As shown in FIG. 3, the produced water Wa tends to stay in the vicinity of the outlet. Such stagnation of generated water also occurs in the anode-side porous body channel 29 in the same manner.

  Therefore, in this embodiment, in order to suppress local stagnation (flooding) of the generated water Wa, in the cathode side porous body channel 28 and the anode side porous body channel 29, the flow rate from the part where the flow rate of the reaction gas is low. The cathode side flow path member 200 and the anode side flow path member 210 are configured so as to guide the flow of the reaction gas to the fast part.

A2-2. Detailed configuration of flow path member:
The detailed configuration of the cathode side porous body channel 28 and the anode side porous body channel 29 will be described with reference to FIGS. FIG. 4 is an explanatory diagram illustrating the gas flow direction FD in the gas flow path in the embodiment. FIG. 5 is an explanatory view illustrating a flow path component that constitutes the gas flow path in the embodiment. FIG. 6 is a cross-sectional view of the cathode-side porous passage 28 configured between the cathode side of the MEGA 25 and the separator 40 in the embodiment. FIG. 7 is a schematic view illustrating the configuration of the channel member disposed in the cathode-side porous channel 28 in the example. Fig.5 (a) is a perspective view of a flow-path structural member, FIG.5 (b) is a front view of a flow-path structural member. The cross-sectional view shown in FIG. 6 is an enlarged view of a circle Y portion in FIG. 2, and also shows the separator 40 and the MEGA 25.

  In the embodiment, as shown in FIG. 4, in the cathode side porous body channel 28, the oxidizing gas flows from below and flows upward. Here, when the flow rate of the central portion B of the cathode-side porous channel 28 is higher than the flow rates of the ends A and C of the cathode-side porous channel 28, as shown in FIG. The cathode-side flow path member 200 is configured such that the oxidizing gas flowing through the portions A and C is directed toward the central portion B where the flow velocity of the oxidizing gas flowing through the end portions A and C is higher than that flowing through the end portions A and C.

  As shown in FIG. 5A, the cathode-side channel member 200 is formed by using a gas channel constituting member 30 in which through holes having the same shape are regularly formed in a metal plate. FIG. 5A shows a partially enlarged view of the cathode-side channel member 200. As shown in FIG. 5 (a), the gas flow path component 30 has a basic structure of corrugated plate portions 32 in which crest portions 32a and trough portions 32b continue alternately, and a plurality of corrugated plate portions 32 are connected. It is a configuration. The plurality of corrugated plate portions 32 have the same shape and the same width W. The connecting portion between the valley portion 32b and the mountain portion 32a forms a single plane (hereinafter, this plane is referred to as a “connecting surface”) S. As can be seen from FIG. A hexagonal through hole H is formed between the next valley 32b and the connecting surface S2 formed by the peaks 32a. The hexagonal through holes H are arranged in a zigzag shape, and when viewed from the front direction, a so-called honeycomb shape is formed as shown in FIG. A broken line in FIG. 5A is attached for the sake of convenience in order to distinguish between two adjacent corrugated plate portions 32. In the gas flow path constituting member 30 used for the cathode side flow path member 28 of the present embodiment, the frequency of the mountain valley is actually about 350, the number of connections of the corrugated plate portions 32 is about 250, and about 87,000 pieces. The hexagonal through hole H is provided.

  In the cathode side flow path member 200 using the gas flow path constituting member 30 in the embodiment, the oxidizing gas flows along the surface of the connecting surface S along the surface of the cathode side of the MEGA 25 as shown by the thick line in FIG. The oxidizing gas that flows toward the cathode and has not been subjected to the power generation reaction at the cathode flows along the surface of the next connecting surface S toward the cathode-side surface of the MEGA 25. Therefore, the oxidizing gas hits the connecting surface S and partly diffuses around, but mainly flows in the depth direction (Z direction in FIG. 5A). The direction in which the reaction gas flows is the above-described “flow direction”.

  A method of forming the cathode-side porous body flow path 28 shown in FIG. 4 using the gas flow path constituting member 30 will be described below with reference to FIG. In addition, in the end part A, the central part B, and the end part C of FIG. 7, the through holes H of the gas flow path component 30 are shown in different sizes as shown in the front view. In A, the center part B, and the edge part C, it has shown typically in order to represent that a flow direction differs. Actually, the size of each through hole H is the same in the end portions A and C and the central portion B. The direction connecting the long sides of the through holes H at the end portions A and C in FIG. 7 represents the flow direction FD.

  As shown in FIG. 7, in the central portion B, the gas flow path component 30 is arranged so that the flow direction of the gas flow path component 30 is substantially parallel to the vertical direction of the gas flow path. In C, the gas flow path constituting member 30 is inclined and arranged so that the flow direction FD faces the central portion B. This “tilting” includes rotating the gas flow path component 30 about the normal of the thin plate when the gas flow path component 30 is considered as a single thin plate. The ends A and C and the central portion B may be joined using, for example, welding or an adhesive. Thus, the cathode side porous body flow path 28 is formed by joining a plurality of gas flow path constituting members 30 having different flow directions. In the embodiment, the gas flow path component 30 disposed in the central portion B corresponds to the “first porous body” in the claims, and the gas flow path component 30 disposed in the end portions A and C is This corresponds to the “second porous body” in the claims.

A2-3. About movement of generated water:
FIG. 8 is an explanatory diagram illustrating the state of movement of the produced water in the example. As described above, in the cathode-side porous channel 28 of the present embodiment, the cathode-side channel member 200 is configured such that the oxidizing gas flows from the portion where the oxidizing gas flow rate is low toward the portion where the oxidizing gas flow rate is high. Is arranged. According to Bernoulli's theorem, the higher the flow velocity, the smaller the pressure generated by the fluid. Therefore, as shown in FIG. 8, the pressure P1 at the central portion B is smaller than the pressure P2 at the ends A and C. As a result, a suction force F corresponding to the pressure difference (P2-P1) acts from the end portions A and C toward the central portion B along the flow direction of the oxidizing gas. Therefore, the generated water Wa locally retained at the end portions A and C is sucked into the central portion B by the suction force F, and is discharged to the outside of the fuel cell by flowing into the oxidizing gas flowing through the central portion B.

  According to the fuel cell of the embodiment described above, the flow path members 200 and 210 for accelerating the movement of the generated water from the slow flow velocity portion to the fast flow velocity portion in the gas flow passage are arranged. Therefore, the movement of the generated water can be promoted from a portion having a low flow rate toward a portion having a high flow rate. Therefore, the drainage of the fuel cell can be improved.

  Further, according to the fuel cell of the embodiment, since the flow path component members 200 and 210 are arranged in the gas flow path so that the reaction gas flows from the low flow rate portion toward the high flow velocity portion, the Bernoulli According to the theorem, a force (suction force) corresponding to the pressure difference acts from a part having a low flow rate to a part having a high flow rate. Accordingly, it is possible to promote the movement of the generated water from a portion where the generated water is likely to stay, in other words, from a portion where the generated water drainage performance is low to a high portion, and to improve drainage to the outside of the fuel cell. Therefore, according to the fuel cell using the cathode side flow path member 200 and the anode side flow path member 210, it is possible to suppress a voltage drop due to flooding and to improve the power generation efficiency of the fuel cell.

  In addition, according to the embodiment, by preparing a plurality of flow path components having a defined flow direction and joining them in different directions, the cathode-side flow path member 200 and the anode-side flow path member 210 are It is manufactured. Therefore, it is possible to easily manufacture a flow path member that guides the flow of the reaction gas in a desired direction.

B. Variations:
(1) In the above-described embodiment, the case where the generated water stays at the end portions A and C of the cathode-side porous channel 28 is described. For example, as shown in FIG. Even in the case where water stays, drainage of the generated water to the outside of the fuel cell can be promoted in the same manner as in the embodiment by directing the flow path from the part where the flow rate of the reaction gas is slow toward the fast part.

  FIG. 9 is an explanatory diagram illustrating the cathode-side channel member 200a disposed in the cathode-side porous channel 28 in the modification. In the present modification, the flow rates of the end portions A and C are higher than the flow rate of the central portion B. Therefore, as shown in FIG. Wa tends to stay. Therefore, as shown in FIG. 9, the central portion B is divided into two regions B1 and B2, and in the region B1 close to the end A, the flow of the reaction gas is guided from the region B1 to the end A, and In the region B2 close to the end C, the cathode side flow path member 200a configured to guide the flow of the reaction gas from the region B2 to the end C is disposed in the cathode side porous body flow channel 28. By doing so, a force (suction force) F corresponding to the pressure difference acts from the regions B1 and B2 where the flow velocity of the reaction gas is low toward the end portions A and C where the flow velocity is high. Can promote the drainage of water.

(2) In the above-described embodiment, the direction of each of the cathode side porous body flow path 28 and the anode side porous body flow path 29 is set so that the reaction gas flows from a portion where the flow velocity of the reaction gas is low to a portion where it is fast. However, for example, at least one of the cathode side porous body channel 28 and the anode side porous body channel 29 may be configured such that the reaction gas flows from a part where the flow rate of the reaction gas is low to a part where it is fast. Good. If only the porous flow path on the side where water is generated is configured as in the embodiment according to the configuration of the fuel cell, flooding can be efficiently suppressed while reducing the manufacturing load of the porous flow path.

(3) In the above-described embodiment to the third embodiment, the vertical fuel cell is described, but the present invention can be applied to, for example, a horizontal fuel cell.

  As mentioned above, although the various Example of this invention was described, this invention is not limited to these Examples, A various structure can be taken in the range which does not deviate from the meaning.

Explanatory drawing which shows schematic structure of the fuel cell 100 in an Example. Sectional drawing which illustrates the structure of the fuel cell in an Example. The schematic diagram explaining the mechanism of the retention of the produced water of the fuel cell in an Example. Explanatory drawing explaining the flow direction of the gas in the gas flow path in an Example. Explanatory drawing which illustrates the flow-path structural member which comprises the gas flow path in an Example. Sectional drawing of the cathode side porous body flow path 28 comprised between the cathode side of MEGA25 and the separator 40 in an Example. The schematic diagram explaining the member for flow paths arrange | positioned in the cathode side porous body flow path in an Example. Explanatory drawing explaining the mechanism of the waste_water | drain of the produced water in an Example. The schematic diagram explaining the member for flow paths arrange | positioned at the cathode side porous body flow path in a modification.

Explanation of symbols

11am ... oxidizing gas supply manifold 11hm ... fuel gas supply manifold 11wm ... cooling water supply manifold 12w ... cooling water supply passage 13wm ... cooling water discharge manifold 17am ... oxidizing gas discharge manifold 17hm ... fuel gas discharge manifold 20 ... power generator 21 ... electrolyte membrane 22a ... Cathode electrode catalyst layer 22b ... Anode electrode catalyst layer 23a ... Gas diffusion layer 23b ... Gas diffusion layer 26 ... Seal gasket 28 ... Cathode side porous channel 29 ... Anode side porous channel 30 ... Gas channel component 32 ... Corrugated plate part 32a ... Mountain part 32b ... Tani part 40 ... Separator 41 ... Cathode side plate 42 ... Intermediate plate 43 ... Anode side plate 100 ... Fuel cell

Claims (4)

A flow path member disposed in a gas flow path for supplying a reaction gas used for power generation of a fuel cell to a membrane electrode assembly,
Formed of a porous body, and has a configuration for promoting the movement of generated water generated by the electrochemical reaction of the fuel cell from a site where the flow rate of the reaction gas in the gas flow path is slow to a fast site, Channel member. The flow path member according to claim 1,
The said structure is a member for flow paths comprised so that the flow of the said reactive gas in the said gas flow path may be directed from the site | part with the slow flow of the said reactive gas to the site | part early. The flow path member according to claim 1 or 2,
The configuration is as follows:
A first porous body that is disposed in a portion of the gas flow path where the flow rate of the reaction gas is fast and guides the flow of the reaction gas in the same direction as the flow direction of the reaction gas;
For the flow path, which is arranged in the gas flow path in a portion where the flow of the reactive gas is slow and is configured by a second porous body that guides the flow of the reactive gas toward the first porous body Element. A fuel cell in which a plurality of membrane electrode assemblies each having electrodes bonded to both surfaces of an electrolyte membrane are stacked with a separator interposed therebetween,
A fuel cell comprising the channel member according to any one of claims 1 to 3 between the membrane electrode assembly and the separator.

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