JP2009259735A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell in which performance can be improved. <P>SOLUTION: The fuel cell is equipped with a membrane electrode structure having an electrolyte membrane, an anode catalyst layer formed on one face of the electrolyte membrane, and a cathode catalyst layer formed on the other face of the electrolyte membrane, and a separator equipped with a plurality of flow passages in which fluid is circulated. In the plurality of flow passages, a plurality of supply flow passages in which the fluid supplied to the membrane electrode structure is circulated, and a plurality of exhaust flow passages in which the fluid exhausted from the membrane electrode structure is circulated are equipped. In the supply flow passages and the exhaust flow passages, entrances or exits are closed, and the aperture width of the supply flow passages and the exhaust flow passages of the separator equipped on the faces opposing to the membrane electrode structure are narrower than the average width of the respective flow passages of the supply flow passages and the exhaust flow passages, while apertures equipped at the supply flow passages and the exhaust flow passages opposed to the outer circumferential side region of the membrane electrode structure are respectively equipped closer toward the outer peripheral side of the membrane electrode structure than toward the center of the respective flow passages of the supply flow passages and the exhaust flow passages. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fuel cell, and more particularly to a fuel cell having a closed channel.

  A fuel cell has a membrane electrode structure (hereinafter referred to as “MEA”) including an electrolyte layer (hereinafter referred to as “electrolyte membrane”) and electrodes (an anode catalyst layer and a cathode catalyst layer) formed on both sides of the electrolyte membrane, respectively. In this case, an electrochemical reaction is caused and the electrical energy generated by the electrochemical reaction is taken out to the outside. Among fuel cells, a polymer electrolyte fuel cell (hereinafter sometimes referred to as “PEFC”) used in a home cogeneration system, an automobile, or the like can be operated in a low temperature region. This PEFC has been attracting attention as a power source and portable power source for electric vehicles because of its high energy conversion efficiency, short start-up time, and small and light system.

  A single cell of PEFC includes a MEA and a pair of current collectors (separators) sandwiching the MEA, and the MEA has a proton conducting polymer that exhibits proton conducting performance by being kept in a water-containing state. Is contained. During operation of the PEFC, a hydrogen-containing gas (hereinafter referred to as “hydrogen”) is supplied to the anode, and an oxygen-containing gas (hereinafter referred to as “air”) is supplied to the cathode. The hydrogen supplied to the anode is separated into protons and electrons under the action of the catalyst contained in the catalyst layer of the anode (hereinafter also referred to as “anode catalyst layer”). It reaches the cathode catalyst layer (hereinafter also referred to as “cathode catalyst layer”) through the layer and the electrolyte membrane. On the other hand, electrons reach the cathode catalyst layer through an external circuit, and through such a process, electric energy can be extracted. Then, protons and electrons that have reached the cathode catalyst layer react with oxygen contained in the air supplied to the cathode catalyst layer, thereby generating water.

  In PEFC in which separators having flow paths through which fluids such as hydrogen and air circulate are arranged on both sides of the MEA, a curved flow path (so-called serpentine shape), a linear flow path, and the like are provided. Is known, and an inlet for fluid flowing into the channel (hereinafter referred to as “channel inlet”) and an outlet for fluid flowing out from the channel (hereinafter referred to as “channel outlet”). However, it is well known that both are not occluded. However, when a fluid is supplied from such a channel to the MEA, the fluid is difficult to diffuse to the MEA region facing the convex portion of the separator sandwiched between the channels, and it is difficult to improve the power generation performance of the single cell. was there. Therefore, for the purpose of improving the diffusibility of the fluid to the MEA region facing the convex portion of the separator, etc., a flow channel in which the flow channel inlet or outlet has been closed so far (hereinafter referred to as “clogged flow channel”). PEFC has been developed in a form that is equipped with

  For example, Patent Document 1 includes a power generation cell having an electrolyte membrane and a separator facing the power generation cell as a technology related to PEFC in a form in which a closed channel is provided. A fuel cell is disclosed in which a gas flow path in which a groove-shaped flow path closed by a closing member and a groove-shaped flow path closed by a closing member are alternately arranged in a stripe shape is formed. . Patent Document 2 discloses a fuel cell in which the width of the opening on the MEA side of the closed channel is smaller than the width of the closed channel at a position away from the MEA. Patent Document 3 discloses a fuel cell in which the opening width of the closed channel is smaller than the maximum width of the closed channel. Patent Document 4 discloses a fuel cell separator in which the width on the opening side of the groove is reduced on the upstream side of the fluid passage and the width on the opening side of the groove is increased on the downstream side of the fluid passage. .

JP 2006-127770 A JP 2005-190983 A JP 2006-114386 A JP 2001-43870 A

  According to the technique disclosed in Patent Document 1, since the closed channel is provided, the power generation performance can be improved by easily diffusing the fluid also in the MEA region facing the convex portion of the separator. It will be possible. However, in the technique disclosed in Patent Document 1, the amount of fluid flowing through the region facing the closed channel is likely to be smaller than the region facing the convex portion of the separator, and the optimum amount for each region There was a problem that it was difficult to supply the fluid. Further, according to the techniques disclosed in Patent Document 2 and Patent Document 3, it is considered that the diffusibility of the fluid in the constituent member in contact with the separator can be improved. However, these techniques have a problem that it is difficult to supply fluid to the outer peripheral side of the MEA. Further, according to the technique disclosed in Patent Document 4, it is considered that a large amount of fluid can be diffused also to the downstream side of the fluid. However, even with such a technique, the fluid is supplied to the outer peripheral side of the MEA. There was a problem that was difficult. That is, with the techniques disclosed in Patent Documents 1 to 4, it is difficult to uniformly supply fluid to substantially the entire surface of the anode catalyst layer and cathode catalyst layer provided in the MEA, and it is difficult to improve performance. There was a problem of being.

  Then, this invention makes it a subject to provide the fuel cell which can improve performance.

In order to solve the above problems, the present invention takes the following means. That is,
The present invention relates to a membrane electrode structure having an electrolyte membrane, an anode catalyst layer formed on one surface of the electrolyte membrane, and a cathode catalyst layer formed on the other surface of the electrolyte membrane, and a plurality of fluids flowing therethrough A separator provided with a flow path, and a plurality of flow paths for supply through which a fluid supplied to the membrane electrode structure circulates, and fluid discharged from the membrane electrode structure. A plurality of discharge channels that circulate, the supply channels and the discharge channels are closed at the inlet or outlet, and the supply channels are provided on the surface of the separator facing the membrane electrode structure And the width of the opening of the discharge channel is narrower than the average channel width of the supply channel and the discharge channel, respectively, and the supply channel and the discharge channel facing the outer peripheral region of the membrane electrode structure The openings provided in the flow paths are the widths of the supply flow path and the discharge flow path, respectively. Characterized in that it is provided Intention to the outer peripheral side of the membrane electrode assembly from the central, a fuel cell.

  Here, “the inlet and outlet of the supply channel and the outlet channel are closed” means that the outlet of the supply channel is the side of the separator (the surface of the separator facing the membrane electrode structure is the front or It means the side surface in the case of the back side, the same shall apply hereinafter), and the discharge channel means that one end on the side adjacent to the inlet of the supply channel is not open on the side surface of the separator. To do. Furthermore, the “average channel width” is the width of the space through which fluid flows when one channel is cut along a plurality of planes whose normal direction is the thickness direction of the membrane electrode structure (channel width) ) Mean value. Further, the “region on the outer peripheral side of the membrane electrode structure” means a membrane electrode structure constituted by a portion closer to the outer periphery of the membrane electrode structure than the center of the surface of the membrane electrode structure facing the separator It means the body area.

  In the present invention, the width of the opening on the outlet side of the supply channel is preferably wider than the width of the opening on the inlet side of the supply channel.

  In the present invention, the width of the opening of the closed channel facing the membrane electrode structure is narrower than the average channel width of the closed channel. By adopting such a configuration, the amount of fluid supplied to the region of the membrane electrode structure facing the closed channel and the amount of fluid supplied to the region of the membrane electrode structure facing the convex portion of the separator The difference can be reduced as compared with the prior art. Furthermore, in the present invention, the opening portion of the closed channel facing the region on the outer peripheral side of the membrane electrode structure is provided from the center of the channel width of the closed channel toward the outer peripheral side of the membrane electrode structure. By adopting such a configuration, a large amount of fluid can also be supplied to the region on the outer peripheral side of the membrane electrode structure. Therefore, according to the present invention, it is possible to provide a fuel cell capable of improving performance by supplying fluid uniformly to substantially the entire surface of the membrane electrode structure.

  Further, in the present invention, the width of the opening on the outlet side of the supply channel is wider than the width of the opening on the inlet side of the supply channel, thereby opposing the outlet side of the supply channel. A large amount of fluid can also be supplied to the region of the electrode structure. By adopting such a configuration, it becomes easy to uniformly supply the fluid to substantially the entire surface of the membrane electrode structure. Therefore, according to the present invention, a fuel cell capable of easily improving performance is provided. be able to.

  The present invention will be described below with reference to the drawings. In addition, the form shown below is an illustration of this invention and this invention is not limited to the form shown below.

  FIG. 1 is a cross-sectional view showing an example of a single cell provided in the fuel cell of the present invention, and the left-right direction in FIG. 1 is the thickness direction of the separator. In FIG. 1, the description of some symbols is omitted. As shown in FIG. 1, the unit cell 10 provided in the fuel cell 100 of the present invention includes an electrolyte membrane 1, an anode catalyst layer 2 formed on one surface of the electrolyte membrane 1, and the other surface of the electrolyte membrane 1. The MEA 4 having the cathode catalyst layer 3 formed on the surface opposite to the surface on which the anode catalyst layer 2 is formed, the gas diffusion layer 5 disposed on the anode catalyst layer 2 side, and the cathode catalyst layer 3 A gas diffusion layer 6 disposed on the side, a separator 7 disposed on the gas diffusion layer 5 side, and a separator 8 disposed on the gas diffusion layer 6 side. The separator 7 has a supply channel 71, 71,... Whose outlet is not open on the side surface of the separator 7, and one end adjacent to the inlet side of the supply channel 71, 71,. The discharge channels 72, 72,... That are not opened are alternately provided, and the separator 8 is supplied with the supply channels 81, 81,. .. Are alternately provided with one end adjacent to the inlet side of the flow channels 81, 81,... Not opening on the side surface of the separator 8.

  During the operation of the fuel cell of the present invention, the hydrogen supplied through the supply channels 71, 71,... And passing through the gas diffusion layer 5 reaches the anode catalyst layer 2 and is contained in the anode catalyst layer 2. An electrochemical reaction in which protons and electrons are generated from hydrogen occurs under the action of the catalyst (for example, platinum, etc.). Protons generated in this way are passed through proton conductors (for example, a fluorine-based proton conducting polymer, etc .; the same shall apply hereinafter) contained in the anode catalyst layer 2, the electrolyte membrane 1, and the cathode catalyst layer 3. Then, it is conducted to the catalyst contained in the cathode catalyst layer 3. On the other hand, the electrons generated in the anode catalyst layer 2 are conducted to the catalyst contained in the cathode catalyst layer 3 via an external circuit. Then, oxygen contained in the air supplied to the cathode catalyst layer 3 via the supply channels 81, 81,... And the gas diffusion layer 6, and protons conducted to the cathode catalyst layer 3. Then, the electrons and the electrons undergo an electrochemical reaction under the action of the catalyst contained in the cathode catalyst layer 3, whereby water is generated in the cathode catalyst layer 3.

  Of the hydrogen supplied to the anode catalyst layer 2 through the supply channels 71, 71,... During the operation of the fuel cell, the hydrogen that was not used for the electrochemical reaction in the anode catalyst layer 2 (hereinafter referred to as “residual” .. Are discharged out of the unit cell 10 through discharge channels 72, 72,... Provided adjacent to the supply channels 71, 71,. Here, since the outlets of the supply channels 71, 71,... Are not opened on the side surfaces of the separator 7, the remaining hydrogen faces the convex portions of the separator 7 from the supply channels 71, 71,. Via the MEA4 region, the discharge channels 72, 72, ... are reached. Therefore, according to the fuel cell of the present invention provided with the supply flow paths 71, 71,... And the discharge flow paths 72, 72,. Of hydrogen can be supplied.

  On the other hand, of the air supplied to the cathode catalyst layer 3 through the supply flow channels 81, 81,... During the operation of the fuel cell, the air that has not been used for the electrochemical reaction in the cathode catalyst layer 3 (in the following) The “remaining air” is discharged out of the unit cell 10 through discharge channels 82, 82,... Provided adjacent to the supply channels 81, 81,. Here, since the outlets of the supply channels 81, 81,... Are not opened on the side surfaces of the separator 8, the remaining air faces the convex portions of the separator 8 from the supply channels 81, 81,. Via the region of the gas diffusion layer 6, it reaches the discharge channels 82, 82,. Therefore, according to the fuel cell of the present invention provided with the supply channels 81, 81,... And the discharge channels 82, 82,. Of air can be supplied.

  FIG. 2 is an enlarged cross-sectional view showing a part of the separator 7 and the gas diffusion layer 5 provided in the fuel cell 100 shown in FIG. 1, and the vertical direction in FIG. 2 is the thickness direction of the separator 7. . Since the separator 7 and the separator 8 have the same form, and the gas diffusion layer 5 and the gas diffusion layer 6 have the same form, the reference numerals of the separator 8 and the gas diffusion layer 6 are added in parentheses in FIG. FIG. 3 is an enlarged cross-sectional view of a part of a conventional fuel cell including a separator having a closed channel whose position of the opening is not controlled. The vertical direction of FIG. It is the thickness direction.

  As shown in FIGS. 1 and 2, the supply flow channels 71, 71,... In the present invention have openings 71x, 71x having a width smaller than the average flow channel width of the supply flow channels 71, 71,. In the present invention, the discharge channels 72, 72,... Have openings 72x, 72x,... That are smaller than the average channel width of the discharge channels 72, 72,. It has been. Similarly, the supply channels 81, 81,... In the present invention are provided with openings 81x, 81x,... That are smaller than the average channel width of the supply channels 81, 81,. In the invention, the discharge channels 82, 82,... Are provided with openings 82x, 82x,... That are smaller than the average channel width of the discharge channels 82, 82,. Further, as shown in FIGS. 1 and 2, the openings 71x, 71x,... And the openings 72x, 72x,... Provided at positions facing the outer peripheral regions of the MEA 4 and the gas diffusion layer 5 are for supply. Are formed closer to the outer peripheral side of the MEA 4 and the gas diffusion layer 5 than the center of the flow path width of the flow paths 71, 71, ... and the discharge flow paths 72, 72, .... Similarly, the openings 81x, 81x,... And the openings 82x, 82x,... Provided at positions facing the outer peripheral regions of the MEA 4 and the gas diffusion layer 6 are supply channels 81, 81,. Are formed closer to the outer peripheral side of the MEA 4 and the gas diffusion layer 6 than the center of the channel width of the channels 82, 82,. On the other hand, in the separator shown in FIG. 3, an opening is formed at a substantially central position of the channel width in all the closed channels.

  As shown in FIGS. 1 to 3, openings 71x, 71x,..., Openings 72x, 72x,..., Openings 81x provided at positions facing the outer peripheral regions of the MEA 4 and the gas diffusion layers 5, 6. , 81x,... And the openings 82x, 82x,... Are formed close to the outer peripheral side of the MEA 4 and the gas diffusion layers 6 and 7, so that the region indicated by A1 in FIG. It can reduce than the area | region shown by. The areas indicated by A1 and A2 on the outer peripheral side are considered to be less likely to be supplied with hydrogen or air than the other areas, but according to the present invention for controlling the position of the opening provided in the closed flow path. For example, hydrogen can be supplied to substantially the entire surface of the anode catalyst layer 2 and the gas diffusion layer 5, and oxygen can be supplied to substantially the entire surfaces of the cathode catalyst layer 3 and the gas diffusion layer 6. Therefore, according to the present invention, the area A1 can be reduced, so that hydrogen is uniformly supplied to substantially the entire surface of the anode catalyst layer 2, and air is uniformly supplied to substantially the entire surface of the cathode catalyst layer 3. By doing so, the fuel cell 100 which can improve performance can be provided.

  FIG. 4 is an enlarged front view showing a part of the separator 7 provided in the fuel cell 100 shown in FIG. 1, and the direction of fluid flow is indicated by arrows. The back / front direction in FIG. 4 is the thickness direction of the separator. Since the separator 7 and the separator 8 have the same shape, the reference numeral of the separator 8 is added in parentheses in FIG. 4, in the fuel cell 100 of the present invention, openings 71x, 71x,... On the outlet side of the supply channels 71, 71,... (Hereinafter referred to as “openings 71a, 71a,...”). Are wider than the widths of the openings 71x, 71x,... (Hereinafter referred to as “openings 71b, 71b,...”) On the inlet side of the supply channels 71, 71,. Further, the width of the openings 72x, 72x,... (Hereinafter referred to as “openings 72a, 72a,...”) Of the discharge channels 72, 72,... Adjacent to the openings 71a, 71a,. 71b, 71b,... Adjacent to 71b, 71b,... (Hereinafter referred to as “openings 72b, 72b,...”) Are wider. In addition, in the fuel cell 100, the width of the openings 81x, 81x,... (Hereinafter referred to as “openings 81a, 81a,...”) On the outlet side of the supply channels 81, 81,. .. Wider than the width of the openings 81x, 81x,... (Hereinafter referred to as “openings 81b, 81b,...”) On the entrance side of the paths 81, 81,. The openings 82x, 82x,... Adjacent to the openings 81a, 81a,... (Hereinafter referred to as “openings 82a, 82a,...”) Are adjacent to the openings 81b, 81b,. 82x, 82x, ... (hereinafter referred to as "openings 82b, 82b, ...").

  As described above, since at least a part of the hydrogen supplied through the supply channels 71, 71,... Is used for the electrochemical reaction in the anode catalyst layer 2, the supply channels 71, 71,. The flow rate of hydrogen flowing in the vicinity of the outlet is less than the flow rate of hydrogen flowing in the vicinity of the inlet of the supply flow channels 71, 71,. Therefore, if the widths of the openings 71a, 71a,... Are the same as the widths of the openings 71b, 71b,..., A smaller amount of hydrogen is supplied from the openings 71a, 71a,. Therefore, in the region of the anode catalyst layer 2 facing the openings 71a, 71a,..., The occurrence frequency of the electrochemical reaction is lower than in the region of the anode catalyst layer 2 facing the openings 71b, 71b,. There is a fear. However, in the fuel cell 100 of the present invention, the widths of the openings 71a, 71a,... Are made larger than the widths of the openings 71b, 71b, ..., and the widths of the openings 72a, 72a,. The width of the convex portion of the separator 7 on the outlet side of the supply passages 71, 71,... Is made larger than the width of the supply passages 71, 71,. It is smaller than the width of the part. By adopting such a configuration, it is possible to reduce the pressure loss of hydrogen on the outlet side of the supply channels 71, 71,... Less than the pressure loss of hydrogen on the inlet side of the supply channels 71, 71,. Therefore, the same amount of hydrogen is supplied to the region of the anode catalyst layer 2 facing the openings 71a, 71a,... As the region of the anode catalyst layer 2 facing the openings 71b, 71b,. Is possible. Therefore, according to the present invention, it is possible to provide the fuel cell 100 that facilitates uniform supply of hydrogen to substantially the entire surface of the anode catalyst layer 2 and can easily improve performance.

  Further, as described above, since at least a part of the air supplied through the supply channels 81, 81,... Is used for the electrochemical reaction in the cathode catalyst layer 3, the supply channels 81, 81. The flow rate of air flowing in the vicinity of the outlets of,... Is smaller than the flow rate of air flowing in the vicinity of the inlets of the supply flow channels 81, 81,. Therefore, if the width of the openings 81a, 81a,... Is the same as the width of the openings 81b, 81b,..., A smaller amount of air is supplied from the openings 81a, 81a,. Therefore, in the region of the cathode catalyst layer 3 facing the openings 81a, 81a,..., The occurrence frequency of the electrochemical reaction is lower than in the region of the cathode catalyst layer 3 facing the openings 81b, 81b,. There is a fear. However, in the fuel cell 100 of the present invention, the widths of the openings 81a, 81a,... Are larger than the widths of the openings 81b, 81b,... And the widths of the openings 82a, 82a,. The width of the convex portion of the separator 8 on the outlet side of the supply channels 81, 81,... Is made larger than the width of the supply channels 81, 81,. It is smaller than the width of the convex part. By adopting such a configuration, it is possible to reduce the pressure loss of air on the outlet side of the supply channels 81, 81,... Less than the pressure loss of air on the inlet side of the supply channels 81, 81,. Therefore, the same amount of air is supplied to the area of the cathode catalyst layer 3 facing the openings 81a, 81a,... As the area of the cathode catalyst layer 3 facing the openings 81b, 81b,. Can do. Therefore, according to the present invention, it is possible to provide the fuel cell 100 that can easily supply air uniformly to substantially the entire surface of the cathode catalyst layer 3 and can easily improve the performance. That is, according to the present invention, the performance can be easily improved by supplying hydrogen uniformly to substantially the entire surface of the anode catalyst layer 2 and supplying air uniformly to the substantially entire surface of the cathode catalyst layer 3. Thus, the fuel cell 100 can be provided.

  In the above description regarding the fuel cell 100 of the present invention, the supply channels 71, 71,..., The discharge channels 72, 72,. Although the supply channel 81, 81,... And the discharge channel 82, 82,... Are illustrated, the cross-sectional shape of the closed channel provided in the fuel cell of the present invention is limited to this. It is not something. The closed channel according to the present invention only needs to be provided with an opening narrower than the average channel width on the surface facing the MEA, and the cross-sectional shape with the axial direction of the closed channel as the normal direction Can be any polygonal shape such as a triangle or a hexagon in addition to a circle.

  In the above description regarding the fuel cell 100 of the present invention, the separator 7 having the supply flow paths 71, 71,... And the discharge flow paths 72, 72,. Although the form provided with the separator 8 which has the flow path 81, 81, ... for which the position and width | variety of the opening part were controlled, and the discharge flow paths 82, 82, ... was illustrated, this invention is limited to the said form. Is not to be done. The fuel cell of the present invention can be configured such that only the position of the opening in the supply channel and / or the discharge channel provided on the surface facing the anode catalyst layer is controlled, and the cathode catalyst Only the position of the opening in the supply channel and / or the discharge channel provided on the surface facing the layer may be controlled. In addition to this, only the position and width of the opening in the supply channel and / or the discharge channel provided on the surface facing the cathode catalyst layer are controlled, or the surface facing the cathode catalyst layer. It is also possible to adopt a form in which only the position and width of the opening in the supply channel and / or the discharge channel are controlled. However, from the viewpoint of making the fuel cell performance easy to improve, at least the position of the opening of the supply channel and / or the discharge channel formed on the surface facing the cathode catalyst layer is controlled. It is preferable to use the form. In the fuel cell of the present invention, the supply flow path and the discharge flow path provided in the separator may be arranged in a so-called counter flow form.

  Moreover, the manufacturing method of the separator with which the fuel cell of this invention is equipped is not specifically limited. In the case where a separator having a closed flow path having an opening having a width narrower than the average flow path width is constituted by one member, for example, a plurality of closed flow paths opened only on one side surface of the separator are provided. After the formation, the holes (openings) penetrating into each of the plurality of closed channels can be manufactured through a process such as forming from the front or the back of the separator. In addition, in the case where the separator according to the present invention is configured by joining two or more members, for example, a closed channel opened on the front surface (or the back surface) and one side surface of the first plate-shaped member is formed. Then, it manufactures through processes, such as joining the front (or back) in which the block passage of the 1st plate-like member is formed, and the 2nd plate-like member which has a slit equivalent to an opening. Can do.

  In the fuel cell system of the present invention, the form of the electrolyte membrane is not particularly limited, and any form usable in a fuel cell in which hydrogen is supplied to the anode side and air is supplied to the cathode side. can do. Furthermore, in the fuel cell system of the present invention, the form of the anode catalyst layer and the cathode catalyst layer is not particularly limited, and can be used in a fuel cell in which hydrogen is supplied to the anode side and air is supplied to the cathode side. Any form can be used.

It is sectional drawing which shows the example of the form of the single cell 10 with which the fuel cell 100 of this invention is equipped. It is sectional drawing which expands and shows a part of separator 7 (separator 8) and gas diffusion layer 5 (gas diffusion layer 6). It is sectional drawing which expands and shows a part of conventional fuel cell. It is a front view which expands and shows a part of separator 7 with which the fuel cell 100 of this invention is equipped.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electrolyte membrane 2 ... Anode catalyst layer 3 ... Cathode catalyst layer 4 ... MEA (membrane electrode structure)
5, 6 ... Gas diffusion layer 7, 8 ... Separator 10 ... Single cell 71, 81 ... Supply flow path 71x, 81x ... Opening 72, 82 ... Discharge flow path 72x, 82x ... Opening 100 ... Fuel cell

Claims (2)

A membrane electrode structure having an electrolyte membrane, an anode catalyst layer formed on one surface of the electrolyte membrane, and a cathode catalyst layer formed on the other surface of the electrolyte membrane, and a plurality of channels through which fluid flows A separator provided with,
A plurality of supply channels through which the fluid supplied to the membrane electrode structure flows through the plurality of channels, and a plurality of discharge streams through which the fluid discharged from the membrane electrode structure flows A road,
The supply channel and the discharge channel are closed at the inlet or the outlet,
The widths of the openings of the supply channel and the discharge channel provided on the surface of the separator facing the membrane electrode structure are the average of the supply channel and the discharge channel, respectively. Narrower than the channel width,
The openings provided in the supply flow channel and the discharge flow channel facing the region on the outer peripheral side of the membrane electrode structure are the flow channel widths of the supply flow channel and the discharge flow channel, respectively. A fuel cell, wherein the fuel cell is provided close to the outer peripheral side of the membrane electrode structure. 2. The fuel according to claim 1, wherein the width of the opening on the outlet side of the supply channel is wider than the width of the opening on the inlet side of the supply channel. battery.

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