JP2008288069A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell which can raise an effectiveness of a controlling effect on deviation and deformation caused by vibration working on a fuel cell composed of a lamination of a plurality of fuel battery cells. <P>SOLUTION: The fuel cell 100 is provided with a separator 130 on which protrusions 140 made of nonconductive rubber are spotted when the fuel battery cells are laminated in a plurality with separators in-between. Each of the spotted protrusions 140 penetrates a gas diffusion member 125 and a gas supplying member 126 in the battery cells and contacts with a membrane electrode assembly 124. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cell in which a plurality of fuel cells are stacked with a separator interposed therebetween.

  A fuel battery cell constituting this type of fuel cell uses a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane as a power generation unit, and gas is applied to the electrodes of the membrane electrode assembly in this power generation unit. The reaction gas is diffused and supplied by the diffusion supply member. That is, even in the fuel cell, the fuel cell has a multi-layered structure, and the fuel cell is mounted on a moving body such as a vehicle in a state where a plurality of the fuel cells are stacked with a separator interposed therebetween. Built into the plant.

  As described above, since the fuel cell itself has a laminated structure of a plurality of members, various joining methods for stacking the cell constituent materials have been proposed for stacking and assembling the cell constituent materials (for example, Patent Document 1). etc).

JP 2004-207071 A JP 2002-237317 A JP-A-11-204122 JP 2005-276820 A JP-A-2005-79059

  According to the method proposed in each of the above-mentioned patent documents, the reliability of securing the seal at the joint portion can be improved by devising the shape and the like while arranging the seal member at the joint portion of the cell constituent material. . However, since the fuel cell has a configuration in which a plurality of fuel cells are stacked, the following problems have been pointed out.

  In a fuel cell in which a plurality of fuel cells are stacked, a vibration having an amplitude in a direction intersecting the cell stacking direction may be applied during the operation. For example, vibration based on driving of a driving device such as a vehicle running or a motor, or vibration based on driving of a driving device other than a fuel cell in a power plant may act on the fuel cell. When such vibrations act on the fuel cell, the individual fuel cell cells may be deformed by displacement between cell constituent materials or shearing force. And this gap and deformation become larger in the stacked fuel cells on both ends than in the cells in other parts.

  In the seal member proposed in each of the above-mentioned patent documents, it is possible to exhibit a suppressing effect for suppressing such displacement and deformation due to shear to some extent. However, since the sealing member is merely disposed so as to surround the electrode, the effectiveness of the suppression effect in the fuel cells on both ends of the fuel cell, where the degree of displacement and deformation increases, may be lacking. is expected. When large vibrations are applied, it is expected that the effectiveness of the suppression effect described above may be lacking not only in the fuel cells on both ends of the fuel cell, but also in the fuel cells in the central region of the stack. The

  The present invention is made in order to solve the above-described problems associated with a fuel cell including a plurality of stacked fuel cell units, and enhances the effectiveness of the effect of suppressing displacement and deformation caused by vibration acting on the fuel cell. For that purpose.

  In order to achieve at least a part of the above object, the present invention adopts the following configuration.

[Application: Fuel cell]
A fuel cell in which a plurality of fuel cell cells each having a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane as a power generation unit are interposed with a separator interposed therebetween,
The fuel cell includes a gas diffusion supply member for diffusing and supplying reactive gas to the electrode in the membrane electrode assembly,
The gist of the invention is that the separator is provided with non-conductive convex bodies that protrude toward the gas diffusion supply member and enter the gas diffusion supply member.

  In the above-described fuel cell, when stacking a plurality of fuel cells with separators interposed therebetween, non-conductive convex bodies are provided on the separator, and each of the dotted convex bodies is attached to a membrane electrode joint. The gas diffusion supply member is protruded toward the gas diffusion supply member for supplying the reaction gas to the electrodes in the body. Accordingly, each convex body of the separator acts against a displacement and a shearing force between the separator and the gas diffusion supply member. Therefore, even when a vibration is applied to the fuel cell, a deviation caused by the vibration is caused. And the effectiveness of the effect of suppressing deformation increases.

  The fuel cell described above can be configured as follows. For example, in the separator, the convex bodies can be scattered in a uniform distribution, or the convex bodies can be scattered at least in the central region of the gas diffusion supply member. In this way, the effectiveness described above is more certain.

  Further, the gas diffusion supply member of the fuel battery cell includes a gas diffusion member bonded to the electrode in the membrane electrode assembly and a porous gas supply member bonded to the member. Thus, the convex body in the separator may be provided so as to penetrate at least the gas supply member of the gas diffusion supply member. If it carries out like this, even if it is a gas diffusion supply member separated into the gas diffusion member and the gas supply member, the effectiveness of the said suppression effect by a convex body can be improved.

  In this case, the convex body can be made to contact the electrode of the membrane electrode assembly through the gas diffusion supply member. In this way, in addition to improving the effectiveness of the suppression effect between the separator and the gas diffusion supply member due to the penetration of the convex body, the membrane electrode assembly is brought into contact with the electrode of the membrane electrode assembly by contact with the electrode. The effect of suppressing displacement and deformation can be exhibited.

  Thus, when the convex body is brought into contact with the electrode of the membrane electrode assembly, the total contact area of the convex body in contact with the electrode is set within a range of 0.1 to 5% of the power generation area of the electrode. That's fine. In this way, since the electrode area involved in power generation can be ensured, an inadvertent decrease in power generation capacity in the fuel cell can be avoided.

  Furthermore, if the convex body is formed of an insulating rubber, it can be prevented from causing any particular trouble in power generation. If the insulating rubber convex body is disposed so as to be compressed in the convex direction, the force accumulated in the rubber convex body resists the displacement and shearing force to resist the compression. Since it can be made to act, it becomes possible to raise the above-mentioned suppression effect more.

  Further, the convex body can be convex in the shape of a cylinder, a prism, a truncated cone, a truncated pyramid, etc., or a rectangular shape, and the long side of the rectangular shape extends from the manifold of the fuel cell. The gas diffusion supply member may be disposed along the direction of the gas flow. By doing so, it is possible to prevent the gas flow from being inadvertently disturbed, so that it is possible to suppress bias in the diffusion supply of the reaction gas to the electrodes. Therefore, an inadvertent decrease in power generation capacity in the fuel cell can be avoided.

  Hereinafter, embodiments of the present invention will be described based on examples. FIG. 1 is an explanatory diagram schematically showing the configuration of a fuel cell 100 as an embodiment of the present invention, and FIG. 2 is an explanatory diagram schematically showing the configuration of a fuel cell 120 constituting the fuel cell 100 in section. 3 is an explanatory view showing the main configuration of the fuel battery cell 120 in an exploded manner.

  As shown in the figure, the fuel cell 100 of this embodiment has a stack structure in which a plurality of fuel cells 120 are stacked with separators 130 interposed. In this case, the number of stacked fuel cells 120 in the fuel cell 100 can be arbitrarily set according to the output required for the fuel cell 100.

  The fuel cell 100 includes an end plate 101a, an insulating plate 102a, and a current collecting plate 103a joined to one end side in the stacking direction, and an end plate 101b, an insulating plate 102b, and a current collecting plate 103b on the other end side. Are provided. The fuel cell 100 includes separators 130 and fuel cells 120 alternately stacked between the current collector plates. In the present embodiment, these each have a horizontally long rectangular shape.

  The fuel cell 100 having the stack structure described above is fastened by a fastening member (not shown) in the stacking direction of the fuel battery cells 120, and a fastening load is applied in the cell stacking direction. With this fastening load, suppression of cell performance degradation due to an increase in contact resistance at any location of the stack structure and prevention of leakage of gas and cooling water flowing inside the fuel cell 100 are achieved.

  In order to distribute and supply hydrogen as a fuel gas, air as an oxidant gas, and cooling water to each fuel cell 120 (specifically, a membrane electrode assembly described later) inside the fuel cell 100. Supply manifold (hydrogen supply manifold, air supply manifold, cooling water supply manifold), anode off-gas and cathode off-gas discharged from the anode and cathode of each fuel cell 120, respectively, and cooling water to collect fuel cell 100 A discharge manifold (an anode offgas discharge manifold, a cathode offgas discharge manifold, and a cooling water discharge manifold) for discharging to the outside is formed.

  As shown in FIG. 1, an air supply port 104i constituting an air supply manifold is formed inside the lower long side of the end plate 101a along the lower long side. A cathode offgas discharge port 104o constituting a cathode offgas discharge manifold is formed along the upper long side inside the upper long side of the end plate 101a. Further, inside the left short side of the end plate 101a, a hydrogen supply port 105i constituting a hydrogen supply manifold and a cooling water supply port 106i constituting a cooling water supply manifold are formed adjacent to each other in the vertical direction. Further, on the right short side of the end plate 101a, a cooling water discharge port 106o constituting a cooling water discharge manifold and an anode off gas discharge port 105o constituting an anode off gas discharge manifold are formed adjacent to each other in the vertical direction.

  Hydrogen as a fuel gas is supplied from a hydrogen tank (not shown) to the hydrogen supply port 105i, and the anode offgas discharged from the anode of the fuel cell 100 is discharged from the anode offgas discharge port 105o. Also, air containing oxygen as an oxidant gas compressed by an air compressor (not shown) is supplied to the air supply port 104i, and the cathode offgas discharged from the cathode of the fuel cell 100 is discharged from the cathode offgas discharge port 104o. Discharged. The cooling water supply port 106i is supplied with cooling water cooled by a radiator (not shown) and pressurized by a pump, flows through the fuel cell 100, is discharged from the cooling water discharge port 106o, and circulates.

  As shown in FIG. 2, a fuel cell 120 stacked in the presence of a separator 130 includes a membrane electrode assembly (MEA: Membrane Electrode) in which electrodes 122 and 123 are bonded to both surfaces of an electrolyte membrane 121 having proton conductivity. Assembly) 124, one electrode as an anode and the other electrode as a cathode, and this membrane electrode assembly 124 is used as a power generation unit. Various electrolyte membranes 121 can be employed, and can be a solid polymer membrane or an electrolyte membrane using a solid oxide or the like as an electrolyte.

  Further, the fuel battery cell 120 has a gas diffusion member 125 and a gas in order to diffusely supply a reactive gas (hydrogen gas for an anode and oxygen for a cathode) to each electrode surface side of the membrane electrode assembly 124. And a supply member 126. The gas diffusion member 125 is joined to the electrode 122 or the electrode 123, and delivers the reaction gas while diffusing to the electrode. The gas supply member 126 is formed of a porous material such as a metal mesh or carbon paper, and supplies the reaction gas supplied through the separator 130 to the gas diffusion member 125. Although the gas diffusion member 125 is porous, it has pores smaller than the gas supply member 126 in order to diffuse the gas to the electrode surface.

  The fuel cell 120 described above is sandwiched by separators 130 from both sides, and the periphery of the cell is sealed with a seal gasket 127 made of, for example, silicon rubber. The seal gasket 127 forms a flow path for the above-described reaction gas (hydrogen gas / air) or cooling water.

  Next, the separator 130 will be described with reference to FIG. As shown in FIGS. 2 and 3, the separator 130 that separates adjacent fuel cells 120 includes a through hole 132i that is continuous with the air supply port 104i of the end plate 101a, and a through hole 132o that is continuous with the cathode offgas discharge port 104o. , A through hole 133i continuous with the hydrogen supply port 105i, a through hole 133o continuous with the anode off-gas discharge port 105o, a through hole 134i continuous with the cooling water supply port 106i, and a through hole 134o continuous with the cooling water discharge port 106o With. These through holes function as a manifold inside the fuel cell described above. The separator 130 supplies air to the fuel cell 120 on one side and supplies hydrogen gas to the fuel cell 120 on the other side. For example, if the upper surface side of the separator 130 in FIG. 3 is the cathode of the fuel cell 120, the separator 130 sends air that has reached the through hole 132i continuous to the air supply port 104i from the pore 135 to the separator upper surface side. The exhaust gas is supplied to the cathode on the upper surface, and the exhaust gas flows into the through hole 132o through the pore 136. On the lower surface side of the separator 130, the hydrogen gas that has reached the through-hole 133 i continuous with the hydrogen supply port 105 i is sent to the separator lower surface side from the pores (not shown) on the separator lower surface side, and supplied to the anode on the separator lower surface. Exhaust gas flows into the through-hole 133o through a pore (not shown).

  The separator 130 includes a plurality of convex bodies 140 protruding toward the fuel cell 120 in addition to the above-described through holes. As shown in FIGS. 2 and 3, the convex body 140 is disposed in a scattered manner in the separator 130, penetrates the gas supply member 126 and the gas diffusion member 125 included in the fuel cell 120, and is a membrane electrode It is in contact with the electrodes 122 and 123 of the joined body 124. FIG. 4 is an explanatory diagram for explaining a contact portion of the convex body 140 with the electrode. As shown in FIG. 4, the separator 130 has a plurality of convex bodies 140 in contact with the central portions 140 c of the electrodes 122 and 123 in the membrane electrode assembly 124, and a plurality of separators 130 are formed around the convex bodies 140. Convex objects 140 are provided in a uniform distribution. Therefore, as shown in FIG. 4, each convex body 140 abuts against the electrode of the membrane electrode assembly 124, and the abutting portion is distributed substantially uniformly around the periphery including the central portion 140c. It will be. In this case, the sum total of the contact areas of the convex bodies 140 at the respective contact positions shown in FIG. 4 is 0.1 to 5 of the electrode power generation area (area of the electrode contributing to power generation in the membrane electrode assembly 124). % Range.

  The relationship between the gas diffusion member 125 and the gas supply member 126 is as follows. The gas diffusion member 125 and the gas supply member 126 respectively have through holes 128 corresponding to the formation pitch of the convex bodies 140 in the separator 130. Therefore, the separator 130 has a plurality of convex bodies 140 penetrating through the members at substantially uniformly distributed locations including the central portions of the gas diffusion member 125 and the gas supply member 126. .

  The convex body 140 is a cylindrical body having a spherical tip, and protrudes from the surface of the separator 130. FIG. 5 is an explanatory view showing a manner of mounting the convex body 140. As shown in FIG. 5, the separator 130 has a three-layer structure in which plates are stacked in three layers, and the lower end protrusion 141 of the convex body 140 is fitted into the hole 131 of the separator 130 so that the convex body 140 is separated into the separator. It can protrude from 130. Alternatively, the lower end flange 142 of the convex body 140 can be fitted into the hole 132 of the separator 130 so that the convex body 140 protrudes from the hole 133 of the separator 130 and the convex body 140 protrudes from the separator 130. Alternatively, the convex body 140 can be adhered to the surface of the separator 130 on its lower surface.

  The above-mentioned convex body 140 is made of various rubber materials such as insulating rubber, for example, silicon rubber, SBR rubber (styrene butadiene rubber), fluorine rubber, butyl rubber, and has elasticity. In this embodiment, the protruding height of the convex body 140 from the separator 130 exceeds the sum of the thicknesses of the gas diffusion member 125 and the gas supply member 126 in the fuel cell 120. As described above, when contacting the electrodes 123 and 124 of the membrane electrode assembly 124 after passing through the gas diffusion member 125 and the gas supply member 126, the state is compressed in the convex direction.

  Next, the manufacturing procedure of the fuel cell 100 of the present embodiment having the above-described configuration will be described. FIG. 6 is a flowchart showing the manufacturing procedure of the fuel cell 100. In manufacturing the fuel cell 100, the step of forming the membrane electrode assembly 124 (Step S100), the step of preparing the gas diffusion member 125 (Step S110), the step of preparing the gas supply member 126 (Step S120), the separator The 130 preparation steps (step S130) are performed in this order, in an appropriate order, or in parallel.

  In the step of forming the membrane / electrode assembly 124, electrode forming catalyst ink is applied to both surfaces of the electrolyte membrane 121 that has been formed into a horizontally long rectangular shape, and dried to form the electrodes 122 and 123. The catalyst ink to be used is obtained by mixing a carbon carrying a catalytic metal (for example, platinum) that promotes an electrochemical reaction between hydrogen and oxygen and an electrolyte solution (for example, an electrolyte solution having the same quality as the electrolyte membrane 121) in an appropriate solvent. It is dispersed. If the electrolyte membrane 121 is a Nafion membrane (Nafion is a registered trademark), a catalyst ink in which carbon carrying a catalyst metal such as platinum is mixed and dispersed in a solvent such as water, ethanol, or polyethylene glycol together with a Nafion solution is used as the electrolyte membrane 121. Apply to dry.

  In the preparation step of the gas diffusion member 125, a through hole 128 (see FIG. 3) having a diameter sufficient to penetrate the convex body 140 is formed in the porous base material for forming the gas diffusion member 125 that has been formed into a horizontally long rectangular shape. To do. The through hole 128 can be formed by machining such as a drill. The same applies to the preparation step of the gas supply member 126, and a through hole 128 having a diameter sufficient to penetrate the convex body 140 is formed in the porous base material for forming the gas supply member 126. In addition, the through-hole 128 can also be formed in the state which joined both the base materials. In the step of preparing the separator 130, as shown in FIG. 3, a plurality of convex bodies 140 are scattered on both surfaces of the separator 130 to form the separator 130 having the convex bodies 140.

  In subsequent step S140, the fuel cell 120 is formed by bonding the gas diffusion member 125 and the gas supply member 126 to both surfaces of the membrane electrode assembly 124 obtained in the above step, and the separator 130 is interposed therebetween. The fuel cells 120 are stacked (stacked). When the gas diffusion member 125 and the gas supply member 126 are bonded to the membrane electrode assembly 124, hot pressing is performed by applying a pressure of about 2 MPa in a temperature environment of, for example, 80 ° C. When stacking the cells with the fuel cell 120 sandwiched between the separators 130, the convex body 140 of the separator 130 enters the through holes 128 of the gas diffusion member 125 and the gas supply member 126, and both members , And the convex body 140 is brought into contact with the electrode of the membrane electrode assembly 124. In this case, the convex body 140 abuts on the electrode while being compressed in the convex direction as described above. When stacking is completed in this manner, the fuel cell 100 is obtained by being fastened by a fastening member (not shown).

  As described above, in this embodiment, in the fuel cell 100 in which a plurality of fuel cells 120 are stacked with the separators 130 interposed, the separators 130 are provided with the convex bodies 140 made of nonconductive rubber. Each of the scattered convex bodies 140 is brought into contact with the electrode of the membrane electrode assembly 124 through the gas diffusion member 125 and the gas supply member 126 in the fuel cell 120. Therefore, the convex body 140 is moved against the deviation between the separator 130 and the gas supply member 126, the deviation between the gas diffusion member 125 and the gas supply member 126, and the deviation between the gas diffusion member 125 and the gas supply member 126 with respect to the separator 130. It can be supported. For this reason, even if the fuel cell 100 shown in FIG. 1 is vibrated in the vertical direction or the horizontal direction in the figure, each convex body 140 of the separator 130 serves as a support as described above. Since the shape body 140 acts against the above-described displacement and shearing force, the displacement and deformation caused by vibration acting on the fuel cell can be effectively suppressed.

  As described above, since the effect of suppressing displacement and deformation due to vibration acting on the fuel cell is achieved in each fuel cell 120, the fastening with the fastening member of the fuel cell is a contact at any part of the stack structure. It is sufficient to avoid the increase in resistance and to prevent leakage of gas / cooling water. For this reason, the fastening member is not required to have a configuration that exerts an effect of suppressing displacement and deformation due to vibration acting on the fuel cell, for example, an improvement in fastening force, a high rigidity of the member, etc. Simplification, weight reduction, etc. can be achieved.

  In addition, in the present embodiment, when the convex bodies 140 are scattered in the separator 130, the convex bodies 140 are scattered in a uniform distribution, and the convex bodies 140 are dispersed in the gas diffusion member 125 and the gas supply member 126. In addition, the membrane electrode assembly 124 was interspersed including the center of the electrode. For this reason, since the support of the convex body 140 works at each location uniformly distributed including the center of the electrode or the like with respect to the above-described deviation, the above-described suppression effect can be achieved more reliably.

  Since the convex body 140 is brought into contact with the electrode of the membrane electrode assembly 124, the contact between the separator 130, the gas diffusion member 125, and the gas supply member 126 with respect to the membrane electrode assembly 144 is also caused by this contact. And the effect of suppressing deformation.

  As described above, when the convex body 140 is brought into contact with the electrode of the membrane electrode assembly 144, in this embodiment, the total contact area of the convex body 140 in contact with the electrode is set to 0.1 to 0.1 of the power generation area of the electrode. It was kept in the range of 5%. Therefore, since the electrode area involved in power generation can be secured, an inadvertent reduction in power generation capacity in the fuel cell 120 can be avoided, which is preferable.

  Furthermore, since the convex body 140 is formed of an insulating rubber, it is possible to ensure the insulation between the separator 130 and the membrane electrode assembly 144. For this reason, it can be made not to interfere with power generation. Since the convex body 140 is disposed so as to be compressed in the convex direction, the force accumulated in the rubber convex body is made to act against displacement and shearing force to resist the compression. Can do. For this reason, the above-described suppression effect can be further enhanced, which is preferable.

  Next, a modified example will be described. FIG. 7 is an explanatory view showing a modification of the convex body. As shown in the figure, in this modification, the separator 130 includes a convex body 140a that is convex in a rectangular shape instead of the cylindrical convex body 140 described above. On the upper surface side of the separator 130 in the drawing, as described above, the air that has reached the through hole 132i flows from the pore 135 through the pore 136 to the through hole 132o. On the other hand, on the lower surface side of the separator 130 in the drawing, as described above, the hydrogen gas that has reached the through hole 133i has a gas flow that flows toward the through hole 133o. Therefore, in this modification, the convex body 140a is arranged so that the long side of the rectangular shape of the convex body 140a is along the above-described gas flow direction on both the upper surface side and the lower surface side of the separator 130. . Therefore, according to this modification, even if the convex shape 140a having a rectangular shape is installed, the gas flow can be prevented from being inadvertently disturbed. Can be suppressed. For this reason, it is possible to avoid an inadvertent decrease in the power generation capacity of the fuel battery cell 120.

  The present invention is not limited to the above-described embodiments and modifications, and can be implemented in various modes without departing from the scope of the invention. For example, the convex body 140 provided in the separator 130 can be a convex shape in a prismatic shape, a truncated cone, a truncated pyramid shape, or the like in addition to a cylindrical shape or a rectangular shape. In this case, a through hole into which the convex body 140 having such a shape enters may be formed in the gas diffusion member 125 or the gas supply member 126.

  In the above-described embodiment, the convex body 140 penetrates the gas diffusion member 125 and the gas supply member 126. However, the convex body 140 penetrates the gas supply member 126 to the gas diffusion member 125. Alternatively, the gas diffusion member 125 may be partially inserted after contacting the gas supply member 126.

  In the above-described embodiment, the fuel battery cell 120 has a configuration in which the gas diffusion member 125 and the gas supply member 126 are joined. However, the electrode in the membrane electrode assembly 124 is formed by a single member. It is also possible to adopt a configuration in which reaction gas is supplied to 122 and 123 by diffusion. Furthermore, the gas diffusion member 125 may be a multi-layer gas diffusion member by providing a difference in porosity and density between the side bonded to the electrode and the side bonded to the gas supply member 126. In this case, the convex body 140 can pass through each layer of the gas diffusion member 125, and the convex body 140 can enter partway through the gas diffusion member 125.

It is explanatory drawing which shows roughly the structure of the fuel cell 100 as an Example of this invention. FIG. 2 is an explanatory diagram schematically showing the configuration of a fuel battery cell 120 constituting the fuel cell 100 in cross section. FIG. 3 is an explanatory diagram showing the main configuration of a fuel cell 120 in an exploded manner. It is explanatory drawing for demonstrating the contact location to the electrode of the convex body. It is explanatory drawing which shows the aspect of mounting | wearing of the convex body. FIG. 5 is a procedure diagram showing a procedure for manufacturing the fuel cell 100. It is explanatory drawing which shows the modification of a convex-shaped body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Fuel cell 101a ... End plate 101b ... End plate 102a ... Insulating plate 102b ... Insulating plate 103a ... Current collecting plate 103b ... Current collecting plate 104i ... Air supply port 104o ... Cathode off-gas discharge port 105i ... Hydrogen supply port 105o ... Anode off gas Discharge port 106i ... Cooling water supply port 106o ... Cooling water discharge port 120 ... Fuel cell 121 ... Electrolyte membrane 122 ... Electrode 123 ... Electrode 124 ... Membrane electrode assembly 125 ... Gas diffusion member 126 ... Gas supply member 127 ... Seal gasket 128 ... through hole 130 ... separator 131 ... hole 132 ... hole 132i ... through hole 132o ... through hole 133 ... hole 133i ... through hole 133o ... through hole 134i ... through hole 134o ... through hole 135 ... pore 136 ... pore 140 ... convex 140a ... Convex 140c ... Central portion 141 ... bottom projections 142 ... lower flange

Claims (9)

A fuel cell in which a plurality of fuel cell cells each having a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane as a power generation unit are interposed with a separator interposed therebetween,
The fuel cell includes a gas diffusion supply member for diffusing and supplying reactive gas to the electrode in the membrane electrode assembly,
The separator is provided with interspersed non-conductive convex bodies protruding toward the gas diffusion supply member and entering the gas diffusion supply member.   The fuel cell according to claim 1, wherein the separator is interspersed with a uniform distribution of the convex bodies. The fuel cell according to claim 1 or 2, wherein
The separator is interspersed with the convex body provided at least in a central region of the gas diffusion supply member. A fuel cell according to any one of claims 1 to 3,
The fuel battery cell is
The gas diffusion supply member includes a gas diffusion member bonded to the electrode in the membrane electrode assembly, and a porous gas supply member bonded to the member,
The separator is
A fuel cell comprising the convex body penetrating at least the gas supply member of the gas diffusion supply member.   The fuel cell according to claim 4, wherein the convex body penetrates the gas diffusion supply member and contacts the electrode of the membrane electrode assembly.   6. The fuel cell according to claim 5, wherein a sum of contact areas where the convex bodies contact the electrodes is in a range of 0.1 to 5% of a power generation area of the electrodes. The fuel cell according to any one of claims 1 to 6,
The convex body is formed of an insulating rubber.   The fuel cell according to claim 7, wherein the convex body is disposed to be compressed in a convex direction. A fuel cell according to any one of claims 1 to 8,
The convex body is formed in a rectangular shape to be convex, and the long side of the rectangular shape is disposed so as to follow the direction of the flow of gas flowing from the manifold of the fuel cell into the gas diffusion supply member. A fuel cell.

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