JP2017126448A - Power generation module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a damage on an electrolyte membrane in a gap between a seal member and a peripheral end surface of a gas diffusion layer and a catalyst layer.SOLUTION: A power generation module comprises: a membrane-electrode assembly including an electrolyte membrane, and a pair of anode-side and cathode-side catalyst layers with the electrolyte membrane located therebetween; a pair of anode-side and cathode-side gas diffusion layers which sandwiches the membrane-electrode assembly located therebetween, and in which a gas diffusion layer on a side of one electrode is smaller than the electrolyte membrane in size; a seal member disposed at a position corresponding to the electrolyte membrane in a direction of lamination of the electrolyte membrane, the pair of catalyst layer and the pair of gas diffusion layer outside a peripheral end surface of the gas diffusion layer on the side of the one electrode; and a support layer disposed to include at least a region corresponding to a gap between the catalyst layer and the gas diffusion layer on the other electrode side opposite to the one electrode side and between the seal member and peripheral end surface when viewed from the direction of lamination, and having a higher rigidity or elasticity than that of the electrolyte membrane.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power generation module constituting a fuel cell.

  As a power generation module constituting a fuel cell, a single cell having a configuration in which a membrane electrode assembly (MEA) is sandwiched between a pair of gas diffusion layers and a separator is used. Further, as such a power generation module, on one electrode side of the membrane electrode assembly, a seal member made of a resin frame is provided outside the outer peripheral end surfaces of the gas diffusion layer and the catalyst layer, so that the membrane electrode assembly and the gas are provided. A power generation module that prevents leakage of reaction gas and generated water between the diffusion layer and the separator may be used. In such a power generation module, a gap may occur between the gas diffusion layer and the catalyst layer and the seal member due to tolerances or manufacturing errors. When such a gap occurs, the electrolyte membrane may be deformed and damaged due to stress concentration on the electrolyte membrane exposed in the gap portion as the electrolyte membrane expands and contracts. Therefore, it has been proposed to dispose a filler in the gap described above to suppress damage to the electrolyte membrane in the gap (see Patent Document 1).

JP2015-125925A

  However, even if the filler is disposed in the gap, the electrolyte membrane cannot be sufficiently supported in such a portion, so that stress concentration accompanying deformation may occur and the electrolyte membrane may be damaged. For this reason, there is a demand for a technique that can suppress damage to the electrolyte membrane in the gap between the outer peripheral end faces of the gas diffusion layer and the catalyst layer and the seal member.

  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.

  (1) According to one embodiment of the present invention, there is provided a power generation module that is used in a stacked manner to constitute a fuel cell. The power generation module includes a membrane electrode assembly having an electrolyte membrane; a pair of catalyst layers on the anode side and cathode side sandwiching the electrolyte membrane; a pair of gas on the anode side and cathode side sandwiching the membrane electrode assembly A pair of gas diffusion layers, each having a gas diffusion layer size on one electrode side smaller than that of the electrolyte membrane; outside the outer peripheral end face of the gas diffusion layer on the one electrode side, A seal member disposed at a position corresponding to the electrolyte membrane in the stacking direction of the electrolyte membrane, the pair of catalyst layers, and the pair of gas diffusion layers; a catalyst on the other electrode side opposite to the one electrode side Between the layer and the gas diffusion layer, it is disposed so as to include at least a region corresponding to the gap between the seal member and the outer peripheral end surface when viewed in the stacking direction, and has higher rigidity or higher than the electrolyte membrane. It comprises; a support layer having a sex.

  According to this configuration, the support layer having higher rigidity or higher elasticity than the electrolyte membrane has a region corresponding to the gap formed between the outer peripheral end face of the gas diffusion layer on one electrode side and the seal member. It is arrange | positioned between the catalyst layer and gas diffusion layer of the other electrode side so that it may include. Therefore, the portion corresponding to the gap in the electrolyte membrane is constrained by such a support layer, and it is possible to suppress the stress due to the deformation from concentrating on the portion, thereby suppressing damage to the electrolyte membrane. In addition, the support layer improves the overall bondability between the electrolyte membrane exposed in the gap, the catalyst layer on the other electrode side, and the gas diffusion layer on the other electrode side, and promotes deterioration of the electrolyte membrane. Since generation of hydrogen oxide and radicals can be suppressed, deformation and breakage due to expansion and contraction of the electrolyte membrane can be suppressed. In addition, for example, the material constituting the gas diffusion layer on the other electrode side can be prevented from piercing the electrolyte membrane in such a region and damaging the electrolyte membrane.

  The present invention can be realized in various forms. For example, the present invention can also be realized in the form of a fuel cell including a power generation module, a fuel cell system including the fuel cell, and a vehicle including the fuel cell system.

It is sectional drawing which shows the structure of the single cell 500 to which the electric power generation module 200 as one Embodiment of this invention is applied. FIG. 2 is an enlarged view of the vicinity of a gap 60 of the power generation module 200 shown in FIG. 1. It is explanatory drawing which shows the single cell 500 at the time of receiving a cell fastening pressure. It is explanatory drawing which shows the single cell 500 at the time of hydrogen deficiency. It is a figure which shows the electric power generation module 250 of a comparative example. It is an expanded sectional view showing power generation module 200a in a 2nd embodiment. It is an expanded sectional view showing power generation module 200b in a 3rd embodiment. It is sectional drawing which shows the electric power generation module 200c in 4th Embodiment. It is an expanded sectional view showing power generation module 200d in a modification.

A. First embodiment:
A1. Schematic configuration of single cell and power generation module:
FIG. 1 is a cross-sectional view showing a configuration of a single cell 500 to which a power generation module 200 according to an embodiment of the present invention is applied. In the present embodiment, the single cell 500 is a solid polymer fuel cell, and is used in a stacked manner to constitute a fuel cell (fuel cell stack). The stacking direction when used by stacking is a direction parallel to the Y axis shown in FIG. The single cell 500 includes a power generation module 200 and a pair of separators 40a and 40c disposed with the power generation module 200 sandwiched in the stacking direction. The separator 40 a is a separator disposed on the anode side of the single cell 500. The separator 40 c is a separator disposed on the cathode side of the single cell 500. Each of the pair of separators 40a and 40c is a substantially rectangular thin plate member, and concave and convex shapes are formed on both surfaces in the stacking direction. Due to the uneven shape, an in-cell gas flow path through which a reaction gas (fuel gas or oxidant gas) flows is formed, and a cooling medium flow path is formed between the separators 40a and 40c of adjacent single cells 500. .

  The power generation module 200 includes a membrane electrode assembly 100, a pair of gas diffusion layers 30a and 30c that sandwich the membrane electrode assembly 100, a seal member 50, and a support layer 70. The membrane electrode assembly 100 includes an electrolyte membrane 10, and an anode side catalyst layer 20 a and a cathode side catalyst layer 20 c that sandwich the electrolyte membrane 10. In the present embodiment, the lower side (−Y direction) of the electrolyte membrane 10 is the anode side, and the upper side (+ Y direction) is the cathode side. The electrolyte membrane 10 is a solid polymer electrolyte membrane, for example, a Nafion membrane. On the lower side (−Y direction) of the electrolyte membrane 10, the anode side catalyst layer 20a is disposed, and on the upper side (+ Y direction), the cathode side catalyst layer 20c is disposed. The anode side catalyst layer 20a and the cathode side catalyst layer 20c are formed of carbon particles supporting a catalyst (for example, platinum) for promoting a fuel cell reaction in the power generation module 200 and an electrolyte resin (ionomer). As shown in FIG. 1, the size of the cathode catalyst layer 20 c in plan view is smaller than the size of the electrolyte membrane 10 in plan view. Therefore, the end portion in the −X direction of the cathode side catalyst layer 20 c is positioned in the + X direction rather than the end portion in the −X direction of the electrolyte membrane 10. On the other hand, the size of the anode catalyst layer 20a in plan view is substantially equal to the size of the electrolyte membrane 10 in plan view.

  On the anode side (−Y direction side) of the membrane electrode assembly 100, an anode side gas diffusion layer 30a is disposed. Further, a cathode side gas diffusion layer 30 c is disposed on the cathode side (+ Y direction side) of the membrane electrode assembly 100. The anode side gas diffusion layer 30a and the cathode side gas diffusion layer 30c diffuse and spread the reaction gas (fuel gas or oxidant gas) over the entire electrode surface. As shown in FIG. 1, the size of the cathode-side gas diffusion layer 30c in plan view is substantially equal to the size of the cathode-side catalyst layer 20c in plan view. Therefore, the size of the cathode-side gas diffusion layer 30 c in plan view is smaller than the size of the electrolyte membrane 10 in plan view. In contrast, the size of the anode-side gas diffusion layer 30a in plan view is substantially equal to the size of the electrolyte membrane 10 and the anode-side catalyst layer 20a in plan view. In this embodiment, both the anode side gas diffusion layer 30a and the cathode side gas diffusion layer 30c are formed of carbon fibers.

  The seal member 50 is disposed on the outer side (−X direction side) of the outer peripheral end face of the cathode side gas diffusion layer 30c. More precisely, the seal member 50 is arranged at a position corresponding to the electrolyte membrane 10 in the stacking direction, outside the outer peripheral end faces (−X direction side) of the cathode side gas diffusion layer 30c and the cathode side catalyst layer 20c. . The seal member 50 prevents leakage of reaction gas, generated water, and the like from between the power generation module 200 and the separators 40a and 40c. In the present embodiment, the seal member 50 is formed of a polymer film (PET (polyethylene terephthalate), PP (polypropylene), PE (polyethylene), PEN (polyethylene naphthalate), or the like) or rubber. For example, butyl rubber or silicone rubber may be employed as the rubber.

  Here, between the outer peripheral end surface of the cathode side gas diffusion layer 30c and the outer peripheral end surface of the cathode side catalyst layer 20c and the seal member 50, that is, the end in the −X direction of the cathode side gas diffusion layer 30c and the cathode side catalyst layer 20c. A gap 60 is formed between the portion and the end of the seal member 50 in the + X direction. Such a gap 60 is caused by tolerance, manufacturing error, aging, and the like. As described above, the size of the cathode-side catalyst layer 20c and the cathode-side gas diffusion layer 30c in plan view is smaller than the size of the electrolyte membrane 10 in plan view, so that the electrolyte membrane 10 is exposed in the gap 60.

  The support layer 70 is disposed between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a. The support layer 70 is disposed so as to include at least a region corresponding to the gap 60 formed on the cathode side. Details of the arrangement position of the support layer 70 will be described later. The support layer 70 is formed of a liquid adhesive member having higher rigidity or higher elasticity than the electrolyte membrane 10. Specifically, in the present embodiment, the support layer 70 is formed of an epoxy resin. Note that the support layer 70 may be formed of any other material having higher rigidity or higher elasticity than the electrolyte membrane 10 instead of the epoxy resin. In the power generation module 200, the electrolyte membrane 10 is supported by providing the support layer 70 having such characteristics. Since the anode side catalyst layer 20a is a porous layer, the bonding property with the electrolyte membrane 10 is low. Similarly, since the anode side gas diffusion layer 30a is a porous layer, the bonding property with the anode side catalyst layer 20a is low. For this reason, the force which supports the electrolyte membrane 10 by the anode side catalyst layer 20a and the anode side gas diffusion layer 30a is low, and deformation of the electrolyte membrane 10 cannot be suppressed by these two layers 20a and 30a. Therefore, in the power generation module 200 of the present embodiment, the support layer 70 is provided to support the electrolyte membrane 10 and suppress deformation of the electrolyte membrane 10. Detailed actions and effects of the support layer 70 will be described later.

  In the present embodiment, the support layer 70 is formed as follows. When the power generation module 200 is manufactured, the support layer 70 is formed by applying an epoxy resin to a predetermined position of the anode side catalyst layer 20a after the membrane electrode assembly 100 is manufactured. Thereafter, the power generation module 200 is formed by thermocompression bonding the pair of gas diffusion layers 30 a and 30 c to the membrane electrode assembly 100 and the support layer 70. The location where the epoxy resin is applied may be the surface of the anode side gas diffusion layer 30a instead of the surface of the anode side catalyst layer 20a or in addition to the surface of the anode side catalyst layer 20a.

A2. Detailed configuration of the support layer 70:
FIG. 2 is an enlarged view of the vicinity of the gap 60 of the power generation module 200 shown in FIG. In FIG. 2, the pair of separators 40a and 40c is omitted. As shown in FIG. 2, the support layer 70 is disposed between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a. The support layer 70 is disposed so as to include a region corresponding to the gap 60 on the cathode side, that is, a region S1 overlapping with the gap 60 when viewed in the Y-axis direction (hereinafter simply referred to as “corresponding region S1”). Yes. Specifically, the position along the X axis of the end surface E3 in the + X direction of the support layer 70 is a distance d1 from the position along the X axis direction of the outer peripheral end surface E2 in the −X direction of the cathode side gas diffusion layer 30c. Only in the + X direction, that is, inside the power generation module 200. Further, the position along the X-axis direction of the end surface in the −X direction of the support layer 70 is equal to the position along the X-axis direction of the end surface in the −X direction of the power generation module 200 as shown in FIG. 1. That is, the position along the X-axis direction of the end surface in the −X direction of the support layer 70 is arranged in the −X direction rather than the position along the X-axis direction of the end surface E1 of the seal member 50. Therefore, when the support layer 70 and the gap 60 are viewed along the stacking direction, the support layer 70 is disposed so as to include the gap 60.

  FIG. 3 is an explanatory diagram showing the single cell 500 when receiving the cell fastening pressure. At the time of cell fastening, the separator 40c receives a fastening pressure F1 from the upper side (+ Y direction) of the single cell 500 to the lower side (−Y direction). Similarly, the separator 40a is applied from below the single cell 500 (−Y direction). The fastening pressure F2 that is directed upward (+ Y direction) is received. Along with this, the membrane electrode assembly 100 similarly receives a fastening pressure. However, in the power generation module 200 of the present embodiment, the support layer 70 having higher rigidity than the electrolyte membrane 10 is provided between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a so as to include the corresponding region S1. Therefore, the fastening pressure is also propagated by the support layer 70 via the anode-side catalyst layer 20a to a portion exposed in the gap 60 in the electrolyte membrane 10 (hereinafter referred to as “exposed portion”). . For this reason, even when the expansion and contraction of the electrolyte membrane 10 occur, the deformation of the exposed portion can be suppressed. The other effect by arrange | positioning the support layer 70 is demonstrated using FIG.

FIG. 4 is an explanatory diagram showing the single cell 500 at the time of hydrogen deficiency. Generally, since the hydrogen diffusion distance is longer at the end of the power generation module 200 than at the center of the power generation module 200, there is a possibility that hydrogen necessary for the electrochemical reaction may not be sufficiently supplied. When the power generation module 200 generates power in such a hydrogen-deficient state, the anode side oxygen reduction reaction (1) together with the oxidation reaction of the carrier carbon on the cathode side (1 / 2C + H ₂ O → 1 / 2CO ₂ + 2H ⁺ + 2e ⁻ ). / 2O ₂ + 2H ⁺ + e ⁻ → H ₂ O) proceeds. As a result, on the cathode side, the adhesive strength between the cathode side gas diffusion layer 30c and the membrane electrode assembly 100 is lowered, and the electrolyte membrane 10 is likely to expand and contract. However, since the power generation module 200 of this embodiment includes the support layer 70 between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a, the above-described oxygen reduction reaction on the anode side can be inhibited. Along with this, the oxidation reaction of the carrier carbon on the cathode side can be suppressed, and a decrease in the adhesive strength between the cathode side gas diffusion layer 30c and the membrane electrode assembly 100 can be suppressed. Therefore, even if the electrolyte membrane 10 is exposed in the gap 60, deformation due to expansion and contraction of the electrolyte membrane 10 can be suppressed.

Further, since the anode side catalyst layer 20a and the anode side gas diffusion layer 30a are not present in the stacking direction (+ Y direction) of the exposed portion, the oxygen supply amount of the exposed portion is large. For this reason, hydrogen and oxygen that permeate from the anode side to the cathode side through the electrolyte membrane 10 react to generate hydrogen peroxide (2H ⁺ + O ₂ + 2e ⁻ → H ₂ O ₂ ). . As a result, the electrolyte membrane 10 is easily deteriorated by hydrogen peroxide. However, since the power generation module 200 of the present embodiment is provided with the support layer 70 between the anode-side catalyst layer 20a and the anode-side gas diffusion layer 30a, the support layer 70 allows hydrogen from the anode side to the cathode side. Since the movement can be blocked, the above-described reaction in which hydrogen peroxide is generated can be suppressed. Therefore, even if the electrolyte membrane 10 is exposed in the gap 60, the deterioration of the electrolyte membrane 10 can be suppressed.

  Further, in the power generation module 200 of the present embodiment, since the support layer 70 exists between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a, the fluff of carbon fibers forming the anode side gas diffusion layer 30a is present. Further, it is possible to suppress the penetration through the catalyst layer 20a to the electrolyte membrane 10.

A3. Comparative example:
FIG. 5 is a diagram showing a power generation module 250 of a comparative example. As shown in FIG. 5, the power generation module 250 in the comparative example is not provided with the support layer 70. Therefore, for example, a fastening pressure is not applied to the gap 90 in a single cell to which the power generation module 250 is applied. For this reason, when the electrolyte membrane 10 is to expand and contract, no fastening pressure is applied to the portion corresponding to the gap 90, so that it can be freely deformed, and the stress concentrates on the portion. As a result, the electrolyte membrane 10 may be deformed or broken. On the other hand, in the power generation module 200 of the first embodiment, since the support layer 70 is provided, the fastening pressure can be applied to the exposed portion, and the electrolyte membrane 10 is restrained to deform the electrolyte membrane 10. Can be suppressed. As a result, stress concentration on the exposed portion can be suppressed and damage to the electrolyte membrane 10 can be suppressed.

  According to the power generation module 200 of the first embodiment described above, the support layer 70 having higher rigidity or higher elasticity than the electrolyte membrane 10 includes the corresponding region S1 corresponding to the gap 60 formed on the cathode side. Furthermore, since the anode side catalyst layer 20a and the anode side gas diffusion layer 30a are disposed between the anode side catalyst layer 20a and the anode side gas diffusion layer 30a, the support layer 70 constrains the exposed portion of the electrolyte membrane 10, and stresses due to deformation of the electrolyte membrane 10 are concentrated on the exposed portion. This can suppress the damage to the electrolyte membrane 10. In addition, the mutual bonding property between the electrolyte membrane 10 exposed in the gap 60 and the anode side catalyst layer 20 a and the anode side gas diffusion layer 30 a can be enhanced via the support layer 70. Further, since the oxygen reduction reaction on the anode side can be suppressed by the support layer 70, the carbon oxidation reaction on the cathode side caused by the reaction is suppressed, and the anode side gas diffusion layer 30a and the membrane electrode assembly 100 are bonded. Can be improved. For this reason, the force which supports the electrolyte membrane 10 can be improved. Further, since the support layer 70 can block the movement of hydrogen from the anode side to the cathode side, generation of hydrogen peroxide and radicals that promote deterioration of the electrolyte membrane 10 can be suppressed. For this reason, deterioration of the electrolyte membrane 10 can be suppressed, and damage to the electrolyte membrane 10 can be suppressed.

B. Second embodiment:
FIG. 6 is an enlarged cross-sectional view showing the power generation module 200a in the second embodiment. In FIG. 6, the vicinity of the gap 60 is shown enlarged in the power generation module 200a of the second embodiment. The power generation module 200a according to the second embodiment is different from the first embodiment in that the membrane electrode assembly 100a is provided instead of the membrane electrode assembly 100 and the support layer 71 is provided instead of the support layer 70. It differs from the power generation module 200 of the form. Since the other structure in the power generation module 200a of 2nd Embodiment is the same as the power generation module 200 of 1st Embodiment, the same code | symbol is attached | subjected to the same component and the detailed description is abbreviate | omitted.

  The membrane electrode assembly 100a differs from the membrane electrode assembly 100 of the first embodiment in that an anode side catalyst layer 21a is provided instead of the anode side catalyst layer 20a. Since other configurations of the membrane electrode assembly 100a are the same as those of the membrane electrode assembly 100, the same components are denoted by the same reference numerals, and detailed description thereof is omitted. The size of the anode side catalyst layer 21a of the second embodiment in plan view is smaller than the size of the anode side gas diffusion layer 30a in plan view. For this reason, as shown in FIG. 6, the end surface in the −X direction of the anode side catalyst layer 21a is positioned in the + X direction from the end surfaces in the −X direction of the anode side gas diffusion layer 30a and the electrolyte membrane 10.

  The support layer 71 of the second embodiment is disposed between the electrolyte membrane 10 and the anode side gas diffusion layer 30a, and also outside the outer peripheral end face of the anode side catalyst layer 21a. As shown in FIG. 6, the support layer 71 is the same as the support layer 70 of the first embodiment in that the support layer 71 is disposed so as to include the corresponding region S1 corresponding to the gap 60 formed on the cathode side. .

  The power generation module 200a of the second embodiment having the above configuration has the same effect as the power generation module 200 of the first embodiment. In addition, since the support layer 71 is directly bonded to the electrolyte membrane 10, the bonding property between itself and the electrolyte membrane 10 can be further improved as compared with the first embodiment, and deformation or breakage of the electrolyte membrane 10 can be prevented. Can be suppressed.

C. Third embodiment:
FIG. 7 is an enlarged cross-sectional view showing a power generation module 200b in the third embodiment. In FIG. 7, the vicinity of the gap 60 is shown enlarged in the power generation module 200b of the third embodiment. The power generation module 200b according to the third embodiment is provided with a membrane electrode assembly 100b instead of the membrane electrode assembly 100, a point provided with a seal member 51 instead of the seal member 50, and supported on the cathode side. It differs from the electric power generation module 200 of 1st Embodiment in the point provided with the layer 72. FIG. Since the other configuration of the power generation module 200b of the third embodiment is the same as that of the power generation module 200 of the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  The membrane electrode assembly 100b is different from the membrane electrode assembly 100 of the first embodiment in that a cathode side catalyst layer 21c is provided instead of the cathode side catalyst layer 20c. Since other configurations of the membrane electrode assembly 100b are the same as those of the membrane electrode assembly 100, the same components are denoted by the same reference numerals, and detailed description thereof is omitted. The size of the cathode side catalyst layer 21c of the third embodiment in plan view is smaller than the size of the cathode side gas diffusion layer 30c in plan view. Therefore, as shown in FIG. 7, the end surface in the −X direction of the cathode side catalyst layer 21c is located in the + X direction with respect to the end surface of the cathode side gas diffusion layer 30c.

  The seal member 51 is different from the seal member 50 in that the thickness (the length in the Y-axis direction) is short, and the other configuration is the same as that of the seal member 50.

  The support layer 72 is disposed between the seal member 51 and the electrolyte membrane 10 and at a position in contact with the electrolyte membrane 10 in the gap 60. The support layer 72 is also disposed in a region surrounded on three sides by the outer peripheral end surface of the cathode side catalyst layer 21 c, the cathode side gas diffusion layer 30 c, and the electrolyte membrane 10. Such a support layer 72 is common to the support layer 70 in that it is disposed so as to include a region S1 corresponding to the gap 60 formed on the cathode side when viewed in the Y-axis direction.

  The power generation module 200b of the third embodiment having the above configuration has the same effect as the power generation module 200 of the first embodiment. In addition, since the support layer 72 is provided in contact with the cathode side surface of the electrolyte membrane 10 exposed in the gap 60 formed on the cathode side, deformation and breakage of the electrolyte membrane 10 can be suppressed.

D. Fourth embodiment:
FIG. 8 is a cross-sectional view showing a power generation module 200c in the fourth embodiment. In FIG. 8, the vicinity of the gap 60 is shown enlarged in the power generation module 200c of the fourth embodiment. The power generation module 200c of the fourth embodiment is the first implementation in that the membrane electrode assembly 100c is provided instead of the membrane electrode assembly 100, and the seal member 52 is provided instead of the seal member 50. It differs from the power generation module 200 of the form. Since the other configuration of the power generation module 200c of the third embodiment is the same as that of the power generation module 200 of the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  The membrane electrode assembly 100c is different from the membrane electrode assembly 100 of the first embodiment in that a cathode side catalyst layer 22c is provided instead of the cathode side catalyst layer 20c. Since the other structure of the membrane electrode assembly 100c is the same as that of the membrane electrode assembly 100, the same components are denoted by the same reference numerals, and detailed description thereof is omitted. The size of the cathode catalyst layer 22c of the fourth embodiment in plan view is substantially equal to the size of the electrolyte membrane 10 in plan view. For this reason, the electrolyte membrane 10 is not exposed in the gap 60.

  The seal member 52 is different from the seal member 50 of the first embodiment in that it is in contact with the cathode side catalyst layer 22c. Specifically, the seal member 52 is disposed in contact with the surface in the + Y direction at the end portion in the −X direction of the cathode side catalyst layer 22c.

  The power generation module 200c of the fourth embodiment having the above configuration has the same effect as the power generation module 200 of the first embodiment. In addition, in the power generation module 200c of the fourth embodiment, since the electrolyte membrane 10 is not exposed in the gap 60, deformation of the portion corresponding to the gap 60 in the electrolyte membrane 10 can be suppressed by the cathode side catalyst layer 22c.

E. Variations:
E1. Modification 1:
FIG. 9 is an enlarged cross-sectional view showing a power generation module 200d in a modified example. The power generation module 200d of the modified example has the anode side and cathode side configurations opposite to those of the power generation module 200 of the first embodiment shown in FIG. Specifically, among the electrolyte membrane 10, the anode side catalyst layer 25a, and the cathode side catalyst layer 25c constituting the membrane electrode assembly 100d, the size of the anode side catalyst layer 25a in plan view is the plane of the electrolyte membrane 10. Smaller than visual size. The size of the cathode-side catalyst layer 25c in plan view is substantially equal to the size of the electrolyte membrane 10 in plan view. The size of the anode-side gas diffusion layer 35a in plan view is smaller than the size of the electrolyte membrane 10 in plan view. The seal member 53 is disposed outside the outer peripheral end surfaces of the anode side catalyst layer 25a and the anode side gas diffusion layer 35a. A gap 65 is formed between the outer peripheral end surfaces of the anode side catalyst layer 25 a and the anode side gas diffusion layer 35 a and the seal member 53. The support layer 73 is disposed between the cathode side catalyst layer 25c and the cathode side gas diffusion layer 35c. The support layer 73 is disposed so as to include a region S2 corresponding to the gap 65, that is, a region S2 that overlaps the gap 65 when viewed in the Y-axis direction.

  The modified power generation module 200d having such a configuration has the same effects as the power generation module 200 of the first embodiment. Therefore, the support layer 73 can suppress the stress from concentrating on the exposed portion of the electrolyte membrane 10 in the gap 65, thereby suppressing damage to the electrolyte membrane 10.

  The present invention is not limited to the above-described embodiments and modifications, and can be realized with various configurations without departing from the spirit of the present invention. For example, the technical features in the embodiments and the modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 10 ... Electrolyte membrane 20a, 21a, 25a ... Anode side catalyst layer 20c, 21c, 22c, 25c ... Cathode side catalyst layer 30a, 35a ... Anode side gas diffusion layer 30c, 35c ... Cathode side gas diffusion layer 40a, 40c ... Separator 50 , 51, 52, 53 ... Seal members 60, 65, 90 ... Gap 70, 71, 72, 73 ... Support layer 100, 100a, 100b, 100c, 100d ... Membrane electrode assembly 200, 200a, 200b, 200c, 200d, 250 ... Power generation module 500 ... Single cell E1, E2, E3 ... End face F1, F2 ... Fastening pressure S1, S2 ... Area (corresponding area)
d1 Distance

Claims (1)

A power generation module used by stacking to constitute a fuel cell,
A membrane electrode assembly having an electrolyte membrane and a pair of catalyst layers on the anode side and the cathode side sandwiching the electrolyte membrane;
A pair of gas diffusion layers on the anode side and cathode side sandwiching the membrane electrode assembly, wherein the gas diffusion layer on one electrode side is smaller in size than the electrolyte membrane; and
It is outside the outer peripheral end surface of the gas diffusion layer on the one electrode side, and is disposed at a position corresponding to the electrolyte membrane in the stacking direction of the electrolyte membrane, the pair of catalyst layers, and the pair of gas diffusion layers. A sealing member;
At least a region corresponding to the gap between the seal member and the outer peripheral end surface when viewed in the stacking direction between the catalyst layer and the gas diffusion layer on the other electrode side opposite to the one electrode side. And a support layer having higher rigidity or higher elasticity than the electrolyte membrane,
A power generation module.

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