Separator for fuel cell and single cell of fuel cell

Abstract

The present application relates to a separator for fuel cells and a single cell of a fuel cell. The separator for fuel cells has an opposing surface configured in an opposing manner to a power generation portion of the fuel cell. A plurality of groove flow paths and a plurality of ribs projecting toward the power generation portion are provided on the opposing surface. At least one of the plurality of ribs is provided with at least one recess located in the center of the rib in the arrangement direction of the plurality of groove flow paths. The recess has a bottom surface opposing the power generation portion and a pair of inner side surfaces rising from both ends in the arrangement direction of the bottom surface. The pair of inner side surfaces are inclined in a manner that the closer to the power generation portion in the opposing direction of the power generation portion and the separator, the farther from the bottom surface in the arrangement direction.

Description

Technical Field

[0001] This disclosure relates to a separator for fuel cells and a single cell of a fuel cell. Background Technology

[0002] A fuel cell is disclosed in Japanese Patent Application Publication No. 2017-188346. The fuel cell includes a membrane electrode gas diffusion layer assembly (MEGA) and a resin frame member disposed on the outer periphery of the MEGA.

[0003] In addition, the fuel cell has a separator on the anode side and cathode side that holds the MEGA and resin frame components.

[0004] MEGA comprises a membrane electrode assembly (MEA) and a gas diffusion layer (GDL) sandwiching the anode and cathode sides of the MEA.

[0005] The separator has multiple channel paths for supplying oxidizing gas or fuel gas (hereinafter referred to as reaction gas) to the MEGA and multiple ribs located between the channel paths and abutting the GDL. Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Furthermore, in such fuel cells, sometimes the portion of the GDL adjacent to the separator that faces the channel flow path flexes and deforms, sinking into the channel flow path. In this case, the sunken GDL becomes a resistance to the reactant gas flowing in the channel flow path, thus potentially increasing the pressure loss of the reactant gas.

[0008] The purpose of this disclosure is to provide a separator for a fuel cell and a single cell of a fuel cell that can suppress the sinking of the gas diffusion layer into the channel flow path.

[0009] Solution for solving the problem

[0010] The first technical solution for achieving the above-mentioned objective includes a separator for a fuel cell having a facing surface configured to face the power generation section of the fuel cell. A plurality of channel passages for the flow of reactant gases are arranged on the facing surface. A plurality of ribs are provided on the facing surface, located between the channel passages and protruding toward the power generation section. At least one of the ribs has at least one recess located at the center of the rib in the arrangement direction of the plurality of channel passages. The recess has: a bottom surface extending along the surface direction of the power generation section and facing the power generation section; and a pair of inner side surfaces rising from both ends of the bottom surface in the arrangement direction. The pair of inner side surfaces are inclined such that they are closer to the power generation section in the facing direction of the power generation section and further away from the bottom surface in the arrangement direction.

[0011] A single cell of a fuel cell for achieving the above-mentioned objective comprises: a pair of separators; and a power generation unit sandwiched between the pair of separators and having a pair of gas diffusion layers respectively abutting against the pair of separators, wherein at least one of the pair of separators is the aforementioned separator, and the power generation unit is recessed into the recess.

[0012] The second technical solution for achieving the above-mentioned objective provides a separator for a fuel cell having opposing surfaces arranged opposite to the power generation section of the fuel cell. Multiple flow channels for the flow of reactant gases are arranged on the opposing surfaces. The separator for the fuel cell comprises: a base material having the multiple flow channels and multiple ribs located between the flow channels and protruding toward the power generation section; and an abutting member abutting the power generation section, the abutting member engaging with one of the multiple ribs. The abutting member has: a base engaging with the rib; and a pair of protrusions protruding from the base and spaced apart from each other in the arrangement direction of the multiple flow channels.

[0013] To achieve the above objective, the second technical solution provides a fuel cell comprising: a pair of separators; and a power generation unit sandwiched between the pair of separators and having a pair of gas diffusion layers respectively abutting against the pair of separators, wherein at least one of the pair of separators is the aforementioned separator, and the power generation unit is recessed into the portion of the base between the protrusions. Attached Figure Description

[0014] Figure 1 This is a first embodiment of a separator for a fuel cell, showing an exploded perspective view of a single cell of the fuel cell.

[0015] Figure 2 This is a top view showing the partition of the first embodiment.

[0016] Figure 3It is along Figure 2 A sectional view along line 3-3.

[0017] Figure 4 This is a cross-sectional view showing the state in which the power generation unit is stacked on the partition body of the first embodiment.

[0018] Figure 5 This is a cross-sectional view showing the state in which the GDL sinks into the recess of the rib.

[0019] Figure 6 It is a cross-sectional view showing the state in which the frame member sinks into the recess of the rib.

[0020] Figure 7 This is a top view showing a modified example of the partition body of the first embodiment.

[0021] Figure 8 This is a second embodiment of a separator for a fuel cell, showing an exploded perspective view of a single cell of the fuel cell.

[0022] Figure 9 This is a top view showing the partition of the second embodiment.

[0023] Figure 10 It is along Figure 9 A sectional view along line 10-10.

[0024] Figure 11 This is a cross-sectional view showing the state in which the power generation unit is stacked on the partition body of the second embodiment.

[0025] Figure 12 This is a cross-sectional view showing the state in which the GDL sinks into the recess of the abutting member.

[0026] Figure 13 It is a cross-sectional view showing the state in which the frame member is recessed into the recess of the abutting member.

[0027] Figure 14 This is a top view showing a modified example of the partition body in the second embodiment. Detailed Implementation

[0028] Implementation Method 1

[0029] The following is for reference Figures 1-6 The first embodiment of the separator for a fuel cell and a single cell of the fuel cell will be described. Furthermore, in the accompanying drawings, for ease of explanation, parts of the structure are exaggerated or simplified; therefore, the dimensional proportions of each structure may differ from the actual dimensions.

[0030] <Overall Structure of a Single Cell in a Fuel Cell Stack>

[0031] like Figure 1As shown, the single cell 190 of the fuel cell stack has a membrane electrode assembly 110 (hereinafter referred to as MEA110), a frame member 120 for holding the MEA110, and a pair of separators 130, 150 for clamping the MEA110 and the frame member 120.

[0032] The single battery 190 is in the shape of a rectangular plate.

[0033] Furthermore, the stacking direction of the partition 130, MEA110 and frame member 120, partition 150 will be described below as the first direction X.

[0034] In addition, the direction that is the length direction of the single cell 190 and is orthogonal to the first direction X will be described as the second direction Y.

[0035] In addition, the direction orthogonal to both the first direction X and the second direction Y will be described as the third direction Z.

[0036] The single cell 190 has inlet holes 191, 193, and 195 for introducing reactant gas or cooling medium into the single cell 190, and outlet holes 192, 194, and 196 for discharging reactant gas and cooling medium from the single cell 190 to the outside. Furthermore, in this embodiment, inlet hole 191 and outlet hole 192 are holes for the flow of fuel gas. Inlet hole 193 and outlet hole 194 are holes for the flow of cooling medium. Inlet hole 195 and outlet hole 196 are holes for the flow of oxidant gas. Here, the fuel gas is hydrogen. The cooling medium is cooling water. The oxidant gas is air.

[0037] Inlet holes 191, 193, 195 and outlet holes 192, 194, 196 are rectangular in plan view, longer in the second direction Y, and penetrate the single cell 190 along the first direction X. Inlet holes 191 and outlet holes 194, 196 are located on one side of the single cell 190 in the second direction Y. Figure 1 (Left side in the left-right direction). The inlet hole 191 and outlet holes 194, 196 are arranged spaced apart from each other in the third direction Z. The outlet hole 192 and inlet holes 193, 195 are located on the other side of the single cell 190 in the second direction Y. Figure 1 (Right side). The outlet hole 192 and the inlet holes 193 and 195 are arranged at intervals in the third direction Z.

[0038] <mea110>

[0039] like Figure 1 As shown, MEA110 is a rectangular shape viewed from above, with a longer length in the second direction Y.

[0040] MEA110 has a solid polymer electrolyte membrane (hereinafter referred to as the electrolyte membrane) not shown and electrodes 111A and 111B disposed on both sides of the electrolyte membrane. Furthermore, in this embodiment, one side of the electrolyte membrane (not shown) in the first direction X (… Figure 1 The electrode that is bonded to the upper side (in the vertical direction) is the cathode electrode 111A. Additionally, the electrode that is bonded to the other side (in the first direction X) of the electrolyte membrane... Figure 1 The electrode that is joined to the lower side of the surface is the anode electrode 111B.

[0041] Electrodes 111A and 111B have a catalyst layer (not shown) bonded to the electrolyte membrane and a gas diffusion layer 112 (hereinafter referred to as GDL112) bonded to the catalyst layer.

[0042] Furthermore, MEA110 is equivalent to the power generation section of the fuel cell disclosed herein.

[0043] <Frame Component 120>

[0044] like Figure 1 As shown, the frame member 120 is a rectangular frame that is longer in the second direction Y.

[0045] The frame member 120 is formed in sheet form, for example, from a synthetic resin material.

[0046] The frame member 120 has through holes 121, 122, 123, 124, 125, and 126 that form holes 191, 192, 193, 194, 195, and 196.

[0047] The frame member 120 has a rectangular opening 127 in the center, which is longer in the second direction Y when viewed from above. MEA110 extends from one side in the first direction X ( Figure 1 The upper side of the frame member 120 is joined to the edge of the opening 127. That is, the frame member 120 is located on the outer periphery of the MEA110.

[0048] <Separator 130>

[0049] like Figure 1 and Figure 2 As shown, the separator 130 is a rectangular plate that is longer in the second direction Y when viewed from above.

[0050] The separator 130 is formed, for example, by stamping a metal component such as titanium or stainless steel.

[0051] The separator 130 is located on the anode electrode 111B side of the MEA110 (refer to...). Figure 1 ).

[0052] The partition 130 has an inner opposing surface 130a opposite to MEA110 and an outer opposing surface 130b opposite to frame member 120.

[0053] The partition 130 has through holes 131, 132, 133, 134, 135, and 136 that form holes 191, 192, 193, 194, 195, and 196. Through holes 131, 134, and 136 are respectively located in the third direction Z, corresponding to through holes 121, 124, and 126 of the frame member 120. Furthermore, through holes 132, 133, and 135 are respectively located in the third direction Z, corresponding to through holes 122, 123, and 125 of the frame member 120.

[0054] The separator 130 has multiple channel passages 137 for the flow of fuel gas and multiple ribs 138 located between the channel passages 137. Furthermore, in Figure 1 In the simplified representation, the outer edge of the portion forming multiple channel flow paths 137 and multiple ribs 138 is shown.

[0055] <Channel Flow 137>

[0056] like Figure 2 As shown, the multiple slot flow paths 137 are slots that connect the through holes 131 and 132. Furthermore, in this embodiment, the six slot flow paths 137 are arranged at intervals between each other in the third direction Z.

[0057] The width of the channel flow path 137, i.e., the cross-sectional area of ​​the flow path, is constant throughout the entire extension direction of the channel flow path 137. The width of each channel flow path 137 is the same.

[0058] The six slot flow paths 137 consist of three first slot flow paths 171 and three second slot flow paths 172. The first slot flow paths 171 and the second slot flow paths 172 are alternately arranged in the third direction Z.

[0059] The first channel flow path 171 has a wavy portion 173 provided on the inner opposite surface 130a and an extension portion 175 extending from the wavy portion 173 to the outer opposite surface 130b.

[0060] The wavy portion 173 extends in a wavy shape along the surface direction of the inner opposing surface 130a. The wavelength λ and amplitude A of the wavy portion 173 are constant throughout the entire extension direction of the wavy portion 173. In addition, the wavy portion 173 has 3 waves.

[0061] The protrusion 175 extends in a straight line from both ends of the wavy portion 173 toward the through holes 131 and 132, respectively.

[0062] The second channel flow path 172 has a corrugated portion 174 provided on the inner opposite surface 130a and an extension portion 176 extending from the corrugated portion 174 to the outer opposite surface 130b. Furthermore, in this embodiment, the corrugated portion 174 has the same waveform as the corrugated portion 173.

[0063] The protrusion 176 extends in a straight line from both ends of the wavy portion 174 toward the through holes 131 and 132, respectively.

[0064] The outermost channel flow path 137 in the third direction Z has a portion located in the third direction Z that is outside the outer edge of the inner opposite surface 130a.

[0065] <rib 138>

[0066] like Figure 3 As shown, multiple ribs 138 are directed towards one side in the first direction X ( Figure 3 The upper side of the vertical direction protrudes.

[0067] like Figure 2 As shown, in this embodiment, the five ribs 138 are arranged at intervals in the third direction Z.

[0068] Each rib 138 has a wavy portion 181 provided on the inner opposing surface 130a and an extension portion 184 extending from the wavy portion 181 to the outer opposing surface 130b. Furthermore, in this embodiment, the outermost wavy portion 181 among the plurality of wavy portions 181 in the third direction Z has a portion located outside the outer edge of the inner opposing surface 130a.

[0069] The wavy portion 181 has a narrow portion 183, and the width W of the narrow portion 183 in the third direction Z is smaller than that of the other portions of the wavy portion 181 (hereinafter referred to as the general portion 182). Furthermore, in this embodiment, the narrow portion 183 is located between the vertices V1 and V2 of the wavy portion 181 and between the vertices V2 and V3 of the wavy portion 181 in the extending direction of the wavy portion 181.

[0070] like Figure 3 As shown, a recess 140 is provided in rib 138 that opens toward the MEA110 side. The recess 140 is located at the center of rib 138 in the third direction Z.

[0071] The recess 140 has a bottom surface 141 extending along the surface direction of MEA110 and opposite to MEA110, and a pair of inner surface surfaces 142 rising from both ends in the third direction Z of the bottom surface 141.

[0072] The height H from the bottom surface 141 to the top of the rib 138 is preferably in the range of 10 μm or more and 30 μm or less. More preferably, this height H is 20 μm or more and 30 μm or less. In this embodiment, this height H is set to 20 μm or more and 30 μm or less.

[0073] The pair of inner surfaces 142 are inclined such that they are closer to MEA110 in the first direction X and further away from the bottom surface 141 in the third direction Z.

[0074] The inclination angle θ of the pair of inner surfaces 142 relative to the bottom surface 141 is preferably in the range of 1 degree or more and 5 degrees or less. Furthermore, this inclination angle θ is more preferably 2 degrees or more and 5 degrees or less. Further, this inclination angle θ is more preferably 3 degrees or more and 5 degrees or less. Furthermore, this inclination angle θ is more preferably 4 degrees or more and 5 degrees or less. In this embodiment, the inclination angle θ is set to 4 degrees or more and 5 degrees or less.

[0075] like Figure 2 As shown, recesses 140 are provided at multiple locations (four in this embodiment) along the extending direction of each rib 138. Two of the four recesses 140 are provided at the wavy portions 181 of the ribs 138. Specifically, recesses 140 are provided at two narrow portions 183. The remaining two recesses 140 are provided at the protruding portions 184 of the ribs 138. Specifically, recesses 140 are provided at the protruding portions 184 extending toward the through hole 131 and the through holes 132, respectively.

[0076] <Channel Flow Path 138A, Rib 137A>

[0077] like Figure 1 and Figure 3 As shown, the partition 130 has a surface 130c on the side opposite to the opposing surfaces 130a and 130b in the first direction X. Multiple channel channels 138A for cooling medium flow are provided on surface 130c, and multiple ribs 137A are located between the channel channels 138A. Ribs 137A are formed by the back surfaces of the channel channels 137. Similarly, channel channels 138A are formed by the back surfaces of the ribs 138. That is, ribs 137A and channel channels 138A are integrally formed with the channel channels 137 and ribs 138 on the opposing surfaces 130a and 130b (see reference). Figure 3 In addition, in Figure 1 In the simplified representation, the outer edge of the portion forming multiple channel flow paths 138A and ribs 137A is shown.

[0078] Multiple channel flow paths 138A are channels that connect through holes 133 and 134. Within channel flow paths 138A, the cooling medium flows in the opposite direction to the fuel gas flowing in channel flow path 137.

[0079] <Separator 150>

[0080] like Figure 1 As shown, the separator 150 is a rectangular plate that is longer in the second direction Y when viewed from above.

[0081] The separator 150 is formed, for example, by stamping metal components such as titanium or stainless steel.

[0082] The separator 150 is provided on the cathode electrode 111A side of the MEA110. The separator 150 has a first surface 150a including a facing surface opposite to the MEA110 and a second surface 150b opposite to the first surface 150a.

[0083] The partition 150 has through holes 151, 152, 153, 154, 155, and 156 that form holes 191, 192, 193, 194, 195, and 196. Through holes 151, 154, and 156 are respectively located in the third direction Z, corresponding to through holes 121, 124, and 126 of the frame member 120. Furthermore, through holes 152, 153, and 155 are respectively located in the third direction Z, corresponding to through holes 122, 123, and 125 of the frame member 120.

[0084] like Figure 1 As shown, the partition 150 has multiple channel flows 157 for the flow of oxidant gas and multiple channel flows 158 for the flow of cooling medium. Furthermore, in Figure 1 In the diagram, the outer edges of the portion forming multiple channel flow paths 157 and the outer edges of the portion forming multiple channel flow paths 158 in the partition body 150 are simplified to represent these, respectively.

[0085] Multiple channel paths 157 are channels that connect through holes 155 and 156. Within channel paths 157, oxidant gas flows in the opposite direction to the fuel gas flowing in channel path 137.

[0086] Multiple channel flow paths 158 are channels that connect through holes 153 and 154. Within channel flow paths 158, the cooling medium flows in the same direction as the oxidant gas flowing in channel flow path 157.

[0087] Next, the function of the first embodiment will be explained.

[0088] like Figure 4 and Figure 5 As shown, when the separator 130, MEA 110, and frame member 120 are stacked to manufacture a single cell 190 of a fuel cell, GDL 112 is recessed into the recess 140 along a pair of inner side surfaces 142 on the inner opposing surfaces 130a of the separator 130. Furthermore, GDL 112 abuts against the bottom surface 141 of the recess 140. As a result, the portion of GDL 112 opposite to the channel flow path 137 becomes extended. Furthermore, in Figure 4 and Figure 5 Only GDL112 in MEA110 is shown in the image.

[0089] On the other hand, such as Figure 6 As shown, on the outer opposite surface 130b of the separator 130, the frame member 120 is recessed into the recess 140 along a pair of inner side surfaces 142. Furthermore, the frame member 120 abuts against the bottom surface 141 of the recess 140. As a result, the portion of the frame member 120 opposite to the channel flow path 137 is extended.

[0090] Next, the effects of the first embodiment will be explained.

[0091] (1) The separator 130 has an inner opposing surface 130a configured to face the MEA 110 of the fuel cell. A plurality of ribs 138 are provided on the inner opposing surface 130a, located between each other in the channel flow paths 137 and protruding toward the MEA 110. A recess 140 is provided in the center of each rib 138 in the third direction Z. The recess 140 has: a bottom surface 141 extending in the surface direction of the MEA 110 and facing the MEA 110; and a pair of inner side surfaces 142 rising from both ends of the bottom surface 141 in the third direction Z. The pair of inner side surfaces 142 are inclined such that the closer they are to the MEA 110 in the first direction X, the further away they are from the bottom surface 141 in the third direction Z.

[0092] Based on this structure, the aforementioned function is achieved. Therefore, it is possible to suppress the sinking of GDL112 into the channel flow path 137.

[0093] (2) The height H from the bottom surface 141 of the recess 140 to the top of the rib 138 is 20 μm or more and 30 μm or less. The inclination angle θ of the pair of inner surfaces 142 relative to the bottom surface 141 is 4 degrees or more and 5 degrees or less.

[0094] According to this structure, the effect of (1) can be properly achieved, and the gap between the bottom surface 141 of the recess 140 and GDL112 can be properly suppressed.

[0095] (3) The recess 140 is provided at multiple points on the inner opposite surface 130a in the extension direction of the rib 138.

[0096] According to this structure, the effect in (1) can be achieved at multiple points in the extension direction of rib 138. Therefore, it is possible to further suppress the sinking of GDL112 into the channel flow path 137.

[0097] (4) The plurality of channel flow paths 137 have a first channel flow path 171 and a second channel flow path 172 that extend in a wavy manner in the surface direction of their inner opposing surfaces 130a and are adjacent to each other in the third direction Z. The plurality of ribs 138 have a wavy portion 181 located between the first channel flow path 171 and the second channel flow path 172. The wavy portion 181 has a narrow portion 183, and the width W of the narrow portion 183 in the third direction Z is smaller than that of the general portion 182 of the wavy portion 181. A recess 140 is provided in the narrow portion 183.

[0098] The smaller the width W of the rib 138 adjacent to the channel flow path 137 in the third direction Z, the easier it is for GDL 112 to sink into the channel flow path 137. In this regard, according to the above structure, a recess 140 is provided in the narrow portion 183 of the rib 138. Therefore, in the portions of the first channel flow path 171 and the second channel flow path 172 adjacent to the narrow portion 183, i.e., the portions where GDL 112 easily sinks into the channel flow path 137, the GDL 112 opposite to this portion can be made to extend. Therefore, the sinking of GDL 112 into the channel flow path 137 can be suppressed.

[0099] Furthermore, according to the above structure, the separator 130 has a first groove flow path 171 and a second groove flow path 172 extending in a wavy manner. Therefore, for example, compared to the case where the plurality of groove flow paths 137 of the separator 130 extend in a straight line in the surface direction of the inner opposing surfaces 130a, when the single cells 190 are stacked on top of each other, the contact portion between the separator 130 of one single cell 190 and the separator 150 of another single cell 190 increases. Therefore, the stability of the contact structure between adjacent separators 130, 150 can be improved, and thus the stability of the contact structure between the single cells 190 can be improved.

[0100] (5) The recesses 140 are respectively provided on multiple ribs 138.

[0101] With this structure, for each of the multiple channel flow paths 137, it is possible to suppress the sinking of GDL112 into the channel flow path 137.

[0102] (6) The partition 130 has an outer opposing surface 130b opposite to the frame member 120. Multiple channel flow paths 137 have protrusions 175, 176 extending outwards from the outer opposing surface 130b. Multiple ribs 138 have protrusions 184 extending outwards from the outer opposing surface 130b. A recess 140 includes a recess 140 provided in the protrusions 184 of the ribs 138.

[0103] In a fuel cell, the MEA110 is held in place by a frame member 120 located on the outer periphery of the MEA110. If such a frame member 120 is formed of a synthetic resin material, sometimes the portion of the frame member 120 opposite to the channel flow path 137 may flex and deform, sinking into the channel flow path 137. In this case, the sunken frame member 120, like the GDL112, becomes a resistance to the fuel gas flowing in the channel flow path 137, and thus may increase the pressure loss of the fuel gas.

[0104] In this respect, according to the above structure, it plays the same role as the above function, and thus can suppress the sinking of the frame member 120 into the channel flow path 137.

[0105] <Example of Change>

[0106] The first embodiment can be implemented in the following modified ways. The first embodiment and the following modifications can be implemented in combination with each other within the scope of technical inconsistency.

[0107] The shapes of the inlet holes 191, 193, 195 and the outlet holes 192, 194, 196 are not limited to the rectangular shape shown in the first embodiment. For example, the shapes of the inlet holes 191, 193, 195 and the outlet holes 192, 194, 196 may also be square or oblong in view.

[0108] The flow of the reactant gas and cooling medium in orifices 191, 192, 193, 194, 195, and 196 is not limited to the flow illustrated in the first embodiment. For example, orifice 196 may be used as an inlet orifice for the oxidant gas, and orifice 195 as an outlet orifice for the oxidant gas. Similarly, orifice 194 may be used as an inlet orifice for the cooling medium, and orifice 193 as an outlet orifice for the cooling medium. That is, the oxidant gas flowing in channel flow path 157 and the cooling medium flowing in channel flow paths 138A and 158 may be configured to flow in the same direction as the fuel gas flowing in channel flow path 137.

[0109] The number of channel paths 137 is not limited to the six illustrated in the first embodiment; it may be five or fewer, or seven or more.

[0110] • As long as the intended effect of this disclosure is achieved, the width of each channel of the channel flow path 137, i.e., the cross-sectional area of ​​the flow path, may not be fixed in the entire extension direction of the channel flow path 137.

[0111] The separator 130 is not limited to the portion of the plurality of channel flow paths 137 illustrated in the first embodiment where the outermost channel flow path 137 in the third direction Z has a position located outside the outer edge of the inner opposing surface 130a. For example, the channel flow path 137 may be located at the same position as the outer edge of the inner opposing surface 130a in the third direction Z, or it may be located inside the outer edge. In addition, it may be configured such that the outermost wavy portion 181 of the plurality of ribs 138 in the third direction Z is located inside the outer edge of the inner opposing surface 130a.

[0112] The recess 140 may not be provided on each rib 138 as illustrated in the first embodiment, but may be provided on at least one rib 138.

[0113] • The partition 130 is not limited to having a recess 140 on the wavy portion 181 of the rib 138 only in the narrow portion 183, as illustrated in the first embodiment. For example, the recess 140 may be provided on both the narrow portion 183 and the general portion 182 on the wavy portion 181, or it may be provided only in the general portion 182.

[0114] • The multiple slot flow paths 137 are not limited to being composed of multiple first slot flow paths 171 and multiple second slot flow paths 172. For example, the multiple slot flow paths 137 only need to have at least one first slot flow path 171 and one second slot flow path 172 that are adjacent to each other, and they may also have slot flow paths that are different from the first slot flow paths 171 and the second slot flow paths 172.

[0115] The second channel flow path 172 is not limited to having the same waveform as the wave portion 173 of the first channel flow path 171 as illustrated in the first embodiment. The wavelength λ, amplitude A, and wave number of the wave portion 174 can be appropriately changed to be different from those of the wave portion 173. In this case, the narrow portion 183 of the rib 138 may not be located between the vertices V1 and V2 of the wave portion 181 and between the vertices V2 and V3, as illustrated in the first embodiment.

[0116] • The shape of the first groove flow path 171 is not limited to the shape illustrated in the first embodiment. That is, the first groove flow path 171 is not limited to the wavelength λ and amplitude A of the wave portion 173 being constant throughout the entire extension direction of the wave portion 173. For example, the wavelength λ and amplitude A of the three waves of the wave portion 173 may be different.

[0117] • The number of waves in the wavy section 173 is not limited to the three illustrated in the first embodiment; it may be two or less, or it may be four or more.

[0118] The recess 140 is not limited to multiple locations on the inner opposing surface 130a in the extending direction of the rib 138, as illustrated in the first embodiment. That is, as... Figure 7 As shown, the recess 140 can also be provided along the entire extending direction of the corrugated portion 181. In this case, the recess 140 provided in the protrusion 184 can also extend from the recess 140 provided in the corrugated portion 181, and can also be provided independently (see reference). Figure 7 Alternatively, the recess 140 can be omitted from the protruding part 184.

[0119] • The shape of the plurality of channel flow paths 137 is not limited to the shape illustrated in the first embodiment, and can be appropriately modified as follows. That is, the plurality of channel flow paths 137 are not limited to the first channel flow path 171 and the second channel flow path 172 that extend in a wavy manner in the surface direction of the inner opposing surface 130a, respectively. For example, each channel flow path 137 may be modified to extend in a straight line in the surface direction of the inner opposing surface 130a.

[0120] The separator for fuel cells disclosed herein is not limited to the separator 130 shown in the first embodiment, which is connected to the anode electrode 111B side of the MEA110, but can also be applied to the separator 150 connected to the cathode electrode 111A side.

[0121] • The separators 130 and 150 are not limited to being formed by stamping metal components; for example, they can also be formed by cutting or etching.

[0122] • The materials used for separators 130 and 150 are not limited to titanium or stainless steel; aluminum or carbon can also be used.

[0123] Implementation Method 2

[0124] The following is for reference Figures 8 to 13 The second embodiment of the separator for the fuel cell and the single cell of the fuel cell will be described. Furthermore, in the accompanying drawings, for ease of explanation, parts of the structure are exaggerated or simplified; therefore, the dimensional proportions of each structure may differ from the actual dimensions.

[0125] <Overall structure of a single cell 290 in a fuel cell stack>

[0126] like Figure 8 As shown, the single cell 290 of the fuel cell stack has a membrane electrode assembly 210 (hereinafter referred to as MEA210), a frame member 220 for holding the MEA210, and a pair of separators 230, 250 for clamping the MEA210 and the frame member 220.

[0127] The single battery 290 is in the shape of a rectangular plate.

[0128] Furthermore, the stacking direction of the partition 230, MEA210 and frame member 220, partition 250 will be described below as the first direction X.

[0129] Furthermore, the direction that is the length direction of the single cell 290 and orthogonal to the first direction X will be described as the second direction Y.

[0130] In addition, the direction orthogonal to both the first direction X and the second direction Y will be described as the third direction Z.

[0131] The single cell 290 has inlet holes 291, 293, and 295 for introducing reactant gas or cooling medium into the single cell 290, and outlet holes 292, 294, and 296 for discharging reactant gas and cooling medium from the single cell 290 to the outside. Furthermore, in this embodiment, inlet hole 291 and outlet hole 292 are holes for the flow of fuel gas. Inlet hole 293 and outlet hole 294 are holes for the flow of cooling medium. Inlet hole 295 and outlet hole 296 are holes for the flow of oxidant gas. Here, the fuel gas is hydrogen. The cooling medium is cooling water. The oxidant gas is air.

[0132] Inlet holes 291, 293, 295 and outlet holes 292, 294, 296 are rectangular in plan view, longer in the second direction Y, and penetrate the single cell 290 along the first direction X. Inlet holes 291 and outlet holes 294, 296 are located on one side of the single cell 290 in the second direction Y. Figure 8 (Left side in the left-right direction). The inlet hole 291 and outlet holes 294, 296 are arranged spaced apart from each other in the third direction Z. The outlet hole 292 and inlet holes 293, 295 are located on the other side of the single cell 290 in the second direction Y. Figure 8 (on the right side). The outlet hole 292 and the inlet holes 293 and 295 are arranged at intervals in the third direction Z.

[0133] <mea210>

[0134] As Figure 8 shown, the MEA 210 is a top view oblong shape that is longer in the second direction Y.

[0135] The MEA 210 has a solid polymer electrolyte film (hereinafter referred to as an electrolyte film) not shown and electrodes 211A, 211B provided on both faces of the electrolyte film. Further, in the present embodiment, the electrode that is bonded to the face of the side (upper side in the up-down direction of Figure 8 ) of the electrolyte film (omitted from the drawing) in the first direction X is a cathode electrode 211A. In addition, the electrode that is bonded to the face of the other side (lower side of Figure 1 ) of the electrolyte film in the first direction X is an anode electrode 211B.

[0136] The electrodes 211A, 211B have a catalyst layer (omitted from the drawing) that is bonded to the electrolyte film and a gas diffusion layer 212 (hereinafter referred to as a GDL 212) that is bonded to the catalyst layer.

[0137] Further, the MEA 210 corresponds to the power generation portion of the fuel cell of the present disclosure.

[0138] <Frame member 220>

[0139] As Figure 8 shown, the frame member 220 is an oblong frame shape that is longer in the second direction Y.

[0140] The frame member 220 is formed in a sheet shape, for example, from a synthetic resin material.

[0141] The frame member 220 has through-holes 221, 222, 223, 224, 225, 226 that constitute holes 291, 292, 293, 294, 295, 296.

[0142] The frame member 220 has an opening portion 227 in a top view oblong shape that is longer in the second direction Y in the center. The MEA 210 is bonded to the edge portion of the opening portion 227 from the side (upper side of Figure 8 ) in the first direction X. That is, the frame member 220 is positioned on the outer peripheral side of the MEA 210.

[0143] <Partition body 230>

[0144] As Figure 8 and Figure 9 shown, the partition body 230 is a top view oblong plate shape that is longer in the second direction Y.

[0145] The partition body 230 is provided on the anode electrode 211B side of the MEA 210 (refer to Figure 8 ).

[0146] The partition 230 has an inner opposing surface 230a opposite to MEA210 and an outer opposing surface 230b opposite to frame member 220.

[0147] The partition 230 includes a substrate 230A constituting the main body of the partition 230 and a plurality of abutting members 240 formed separately from the substrate 230A (see reference). Figure 9 ).

[0148] <Substrate 230A>

[0149] The substrate 230A is formed, for example, by stamping metal components such as titanium and stainless steel.

[0150] The substrate 230A has through holes 231, 232, 233, 234, 235, and 236 that form holes 291, 292, 293, 294, 295, and 296. Through holes 231, 234, and 236 are respectively located in the third direction Z corresponding to through holes 221, 224, and 226 of the frame member 220. Furthermore, through holes 232, 233, and 235 are respectively located in the third direction Z corresponding to through holes 222, 223, and 225 of the frame member 220.

[0151] The substrate 230A has multiple channel passages 237 for the flow of fuel gas and multiple ribs 238 located between the channel passages 237. Furthermore, in Figure 8 In simplified representation, the outer edge of the portion in the substrate 230A in which multiple groove flow paths 237 and multiple ribs 238 are formed is shown.

[0152] like Figure 9 As shown, the multiple slot flow paths 237 are slots that connect the through holes 231 and 232. Furthermore, in this embodiment, the six slot flow paths 237 are arranged at intervals between each other in the third direction Z.

[0153] The width of the channel flow path 237, i.e., the cross-sectional area of ​​the flow path, is constant throughout the entire extension direction of the channel flow path 237. The width of each channel flow path 237 is the same.

[0154] Each channel flow path 237 has a wavy portion 237a provided on the inner opposite surface 230a and an extension portion 237b extending from the wavy portion 237a to the outer opposite surface 230b.

[0155] The wavy portion 237a extends in a wavy shape along the surface direction of the inner opposing surface 230a. The wavelength λ and amplitude A of the wavy portion 237a are constant throughout its entire extension direction. Furthermore, the wavy portion 237a has three wave numbers. In this embodiment, each wavy portion 237a has the same waveform. Additionally, in this embodiment, the outermost wavy portion 237a in the third direction Z has a portion located further outward than the outer edge of the inner opposing surface 230a.

[0156] The protrusion 237b extends in a straight line from both ends of the wavy portion 237a toward the through holes 231 and 232, respectively.

[0157] like Figure 10 As shown, multiple ribs 238 are directed towards one side in the first direction X ( Figure 10 The upper side of the vertical direction protrudes.

[0158] like Figure 9 As shown, in this embodiment, the five ribs 238 are arranged at intervals in the third direction Z.

[0159] Each rib 238 has a wavy portion 238a provided on the inner opposing surface 230a and a protruding portion 238b extending from the wavy portion 238a to the outer opposing surface 230b. Furthermore, in this embodiment, the outermost wavy portion 238a among the plurality of wavy portions 238a in the third direction Z has a portion located outside the outer edge of the inner opposing surface 230a.

[0160] like Figure 8 and Figure 10 As shown, the substrate 230A has a surface 230c on the side opposite to the opposing surfaces 230a and 230b in the first direction X. Multiple channel channels 238A for cooling medium flow are provided on surface 230c, and multiple ribs 237A are located between the channel channels 238A. The ribs 237A are formed by the back surfaces of the channel channels 237. Furthermore, the channel channels 238A are formed by the back surfaces of the ribs 238. That is, the ribs 237A and the channel channels 238A are integrally formed with the channel channels 237 and ribs 238 on the opposing surfaces 230a and 230b (see reference). Figure 10 In addition, in Figure 8 In the simplified representation, the outer edge of the portion having multiple channel flow paths 238A and multiple ribs 237A is shown.

[0161] Multiple slot flow paths 238A are slots that connect through holes 233 and 234. Within slot flow paths 238A, the cooling medium flows in the opposite direction to the fuel gas flowing in slot flow path 237.

[0162] <Abutting Component 240>

[0163] like Figure 10 As shown, the abutting member 240 is a member that abuts against GDL212 of MEA210, and is formed of a conductive material different from the substrate 230A. In detail, the abutting member 240 is formed using a conductive material comprising a bonding material composed of a thermosetting resin such as epoxy resin and conductive particles such as carbon.

[0164] Each abutment member 240 has a base 241 that engages with the corresponding rib 238 and a pair of protrusions 242 that protrude from the base 241.

[0165] The base 241 has a bottom surface 241a that extends between the protrusions 242 in the surface direction of MEA210 and is opposite to MEA210, and a mating surface 241b that is located on the side opposite to the bottom surface 241a in the first direction X and engages with the top surface 238c of the rib 238.

[0166] The base 241 covers the entire top surface 238c of the rib 238 in the third direction Z. Each abutment member 240 is fixed to the substrate 230A by bonding the two ends of the mating surface 241b in the third direction Z with an adhesive (not shown).

[0167] A pair of protrusions 242 are spaced apart from each other in the third direction Z. Each pair of protrusions 242 has an inner surface 242a that rises from the bottom surface 241a in the third direction Z. That is, in the abutment member 240, a recess 243 is formed between the protrusions 242, consisting of the bottom surface 241a and the pair of inner surfaces 242a. The inner surfaces 242a are inclined such that the closer they are to the MEA210 in the first direction X, the further away they are from the bottom surface 241a in the third direction Z.

[0168] The height H from the bottom surface 241a of the base 241 to the top of the pair of protrusions 242 is preferably in the range of 10 μm or more and 30 μm or less. More preferably, this height H is 20 μm or more and 30 μm or less. In this embodiment, this height H is set to 20 μm or more and 30 μm or less.

[0169] The inclination angle θ of the pair of inner surfaces 242a relative to the bottom surface 241a is preferably in the range of 1 degree or more and 5 degrees or less. Furthermore, this inclination angle θ is more preferably 2 degrees or more and 5 degrees or less. Further, this inclination angle θ is more preferably 3 degrees or more and 5 degrees or less. Furthermore, this inclination angle θ is more preferably 4 degrees or more and 5 degrees or less. In this embodiment, the inclination angle θ is set to 4 degrees or more and 5 degrees or less.

[0170] like Figure 9 As shown, the abutment member 240 is bonded to both the corrugated portion 238a and the protruding portion 238b. In detail, the abutment member 240 is provided along the entire extension direction of the corresponding rib 238.

[0171] The abutment members 240 are respectively provided on 5 ribs 238.

[0172] <Separator 250>

[0173] like Figure 8 As shown, the separator 250 is a rectangular plate that is longer in the second direction Y when viewed from above.

[0174] The separator 250 is formed, for example, by stamping metal components such as titanium or stainless steel.

[0175] The separator 250 is provided on the cathode electrode 211A side of the MEA210. The separator 250 has a first surface 250a including a facing surface opposite to the MEA210 and a second surface 250b opposite to the first surface 250a.

[0176] The partition 250 has through holes 251, 252, 253, 254, 255, and 256 that form holes 291, 292, 293, 294, 295, and 296. Through holes 251, 254, and 256 are respectively located in the third direction Z, corresponding to through holes 221, 224, and 226 of the frame member 220. Furthermore, through holes 252, 253, and 255 are respectively located in the third direction Z, corresponding to through holes 222, 223, and 225 of the frame member 220.

[0177] like Figure 8 As shown, the partition 250 has multiple channel channels 257 for the flow of oxidant gas and multiple channel channels 258 for the flow of cooling medium. Furthermore, in Figure 8 In the diagram, the outer edges of the portion forming multiple channel flow paths 257 and the outer edges of the portion forming multiple channel flow paths 258 in the partition body 250 are simplified to represent these, respectively.

[0178] Multiple channel paths 257 are channels that connect through holes 255 and 256. Within channel paths 257, oxidant gas flows in the opposite direction to the fuel gas flowing in channel path 237.

[0179] Multiple channel flow paths 258 are channels that connect through holes 253 and 254. Within channel flow paths 258, the cooling medium flows in the same direction as the oxidant gas flowing in channel flow path 257.

[0180] Next, the function of the second embodiment will be explained.

[0181] like Figure 11 As shown, a separator 230, an MEA 210, and a frame member 220 are stacked to manufacture a single cell 290 of a fuel cell. At this time, on the inner opposing surfaces 230a of the separator 230, a pair of protrusions 242 of the abutment member 240, which is bonded to the wavy portion 238a of the rib 238, and the GDL 212 of the MEA 210 are in abutment. Thus, as... Figure 12 As shown, a pair of protrusions 242 of the abutment member 240 engage with the GDL 212 of the MEA 210, and the GDL 212 sinks into the recess 243 formed between the protrusions 242 in the abutment member 240. Furthermore, the GDL 212 abuts against the bottom surface 241a of the base 241. As a result, the portion of the GDL 212 opposite to the channel flow path 237 becomes extended. Furthermore, in Figure 11 and Figure 12 Only GDL212 in MEA210 is shown in the image.

[0182] On the other hand, on the opposite outer surface 230b of the partition 230, a pair of protrusions 242 of the abutting member 240, which is bonded to the protrusion 238b of the rib 238, and the frame member 220 are in an abutting state. Thus, as Figure 13 As shown, a pair of protrusions 242 of the abutting member 240 engage with the frame member 220, and the frame member 220 is recessed into the recess 243 formed between the protrusions 242 in the abutting member 240. Furthermore, the frame member 220 abuts against the bottom surface 241a of the base 241. As a result, the portion of the frame member 220 opposite to the channel flow path 237 becomes extended.

[0183] Next, the effects of the second embodiment will be explained.

[0184] (7) The separator 230 includes a substrate 230A and an abutment member 240. The substrate 230A has a plurality of channel flow paths 237 and a plurality of ribs 238 located between the channel flow paths 237 and protruding toward the MEA 210. The abutment member 240 engages with the ribs 238 and abuts against the MEA 210. The abutment member 240 has a base 241 that engages with the ribs 238 and a pair of protrusions 242 that protrude from the base 241 and are spaced apart from each other in a third direction Z, which is the arrangement direction of the plurality of channel flow paths 237.

[0185] Based on this structure, the aforementioned function is achieved. Therefore, it is possible to suppress the sinking of GDL212 into the channel flow path 237.

[0186] Furthermore, according to the above structure, by providing the abutment member 240, the protrusion height of the rib 238 of the substrate 230A can be reduced by an amount corresponding to the height of the abutment member 240. Therefore, the forming of the substrate 230A of the partition 230 can be facilitated, thereby making the manufacturing of the partition 230 easier.

[0187] (8) The base 241 has a bottom surface 241a extending between the protrusions 242 in the surface direction of MEA210 and opposite to MEA210. The pair of protrusions 242 have an inner surface 242a that rises from the bottom surface 241a in the third direction Z. The inner surface 242a is inclined such that it is closer to MEA210 in the first direction X, which is the direction opposite to MEA210 and the separator 230, and further away from the bottom surface 241a in the third direction Z.

[0188] With this structure, compared to the case where the inner surfaces 242a of the pair of protrusions 242 stand vertically relative to the bottom surface 241a, the GDL 212 sinks along the pair of inner surfaces 242a. As a result, the portion of the GDL 212 opposite to the channel flow path 237 becomes more extended. Therefore, it is possible to further suppress the sinking of the GDL 212 into the channel flow path 237.

[0189] (9) The height H from the bottom surface 241a of the base 241 to the top of the pair of protrusions 242 is 20 μm or more and 30 μm or less. The inclination angle θ of the pair of inner surfaces 242a relative to the bottom surface 241a is 4 degrees or more and 5 degrees or less.

[0190] According to this structure, the effect in (8) can be properly achieved, and the gap between the bottom surface 241a of the base 241 and GDL212 can be properly suppressed.

[0191] (10) The abutment member 240 is provided in the entire extension direction of the rib 238.

[0192] With this structure, it is possible to suppress the sinking of GDL212 into the channel flow path 237 along the entire extension direction of rib 238. Furthermore, the number of abutment members 240 arranged in the extension direction of rib 238 can be reduced to one. Therefore, compared to the case where multiple abutment members 240 are provided in the extension direction of rib 238, the manufacture of the partition 230 can be made easier.

[0193] (11) The abutting members 240 are respectively provided on multiple ribs 238.

[0194] With this structure, for each of the multiple channel flow paths 237, it is possible to suppress the sinking of GDL212 into the channel flow path 237.

[0195] (12) The separator 230 has an outer facing surface 230b opposite to the frame member 220. Multiple channel flow paths 237 have protrusions 237b extending outwards from the outer facing surface 230b. Multiple ribs 238 have protrusions 238b extending outwards from the outer facing surface 230b. An abutment member 240 is also provided at the protrusions 238b of the ribs 238.

[0196] In a fuel cell, the MEA210 is held in place by a frame member 220 located on the outer periphery of the MEA210. If such a frame member 220 is formed of a synthetic resin material, sometimes the portion of the frame member 220 opposite to the channel flow path 237 may flex and deform, sinking into the channel flow path 237. In this case, the sinking frame member 220, like the GDL212, becomes a resistance to the fuel gas flowing in the channel flow path 237, and thus may increase the pressure loss of the fuel gas.

[0197] In this respect, according to the above structure, it plays the same role as the above function, and thus can suppress the sinking of the frame member 220 into the channel flow path 237.

[0198] <Example of Change>

[0199] The second embodiment can be implemented in the following modified ways. The second embodiment and the following modifications can be implemented in combination with each other within the scope of technical inconsistency.

[0200] The shapes of the inlet holes 291, 293, 295 and the outlet holes 292, 294, 296 are not limited to the rectangular shape shown in the second embodiment. For example, the shapes of the inlet holes 291, 293, 295 and the outlet holes 292, 294, 296 may also be square or oblong in view.

[0201] The flow of the reactant gas and cooling medium in orifices 291, 292, 293, 294, 295, and 296 is not limited to the flow illustrated in the second embodiment. For example, orifice 296 may be used as an inlet orifice for the oxidant gas, and orifice 295 as an outlet orifice for the oxidant gas. Similarly, orifice 294 may be used as an inlet orifice for the cooling medium, and orifice 293 as an outlet orifice for the cooling medium. That is, the oxidant gas flowing in channel flow path 257 and the cooling medium flowing in channel flow paths 238A and 258 may be configured to flow in the same direction as the fuel gas flowing in channel flow path 237.

[0202] The number of channel paths 237 is not limited to the six illustrated in the second embodiment; it may be five or fewer, or seven or more.

[0203] • The separator 230 is not limited to having the same shape for each of the wave sections 237a as illustrated in the second embodiment. That is, each channel flow path 237 is not limited to having a wavelength λ and amplitude A of each wave section 237a that are constant throughout the entire extension direction of the wave section 237a. For example, the wavelength λ and amplitude A of the three waves of each wave section 237a may be different.

[0204] • The number of waves in each wave section 237a is not limited to the three illustrated in the second embodiment; it may be two or less, or it may be four or more.

[0205] • As long as the desired effect of this disclosure can be achieved, the width of each channel 237, i.e., the cross-sectional area of ​​the channel, does not have to be fixed in the entire extension direction of the channel 237.

[0206] The separator 230 is not limited to the portion of the plurality of corrugated portions 237a exemplified in the second embodiment that is located outside the outermost corrugated portion 237a in the third direction Z, which is positioned outside the outer edge of the inner opposing surface 230a. For example, the corrugated portion 237a may be located at the same position as the outer edge of the inner opposing surface 230a in the third direction Z, or it may be located inside the outer edge. In addition, the corrugated portion 238a exemplified in the plurality of corrugated portions 238a that is located outside the outermost corrugated portion 238a in the third direction Z may be located inside the outer edge of the inner opposing surface 230a.

[0207] • The partition 230 is not limited to the abutting member 240 provided on each rib 238 as illustrated in the second embodiment, as long as the abutting member 240 is provided relative to at least one rib 238.

[0208] The abutment member 240 may not be limited to being provided along the entire extending direction of the rib 238 as illustrated in the second embodiment. That is, as... Figure 14 As shown, the partition 230 can also be a plurality of abutment members 240 provided at intervals from each other in the extending direction of the rib 238. Furthermore, the partition 230 is not limited to bonding the abutment members 240 to both the corrugated portion 238a and the protruding portion 238b of the rib 238; it is also possible for the abutment members 240 to be bonded to only either the corrugated portion 238a or the protruding portion 238b. In any case, it is acceptable as long as the partition is configured such that the protrusion height of the portion of the rib 238 where the abutment members 240 are not provided is increased by an amount corresponding to the height of the abutment members 240.

[0209] The channel flow path 237 is not limited to having a wavy portion 237a that extends in a wavy manner in the surface direction of the inner opposing surface 230a, as illustrated in the second embodiment. For example, at least one of the multiple channel flow paths 237 may extend in a straight manner in the surface direction of the inner opposing surface 230a.

[0210] The shape of the abutting member 240 is not limited to the shape illustrated in the second embodiment, and can be modified as follows: The shape of the recess 243 of the abutting member 240 is not limited to the bottom surface 241a extending along the surface direction of the MEA210 as illustrated in the second embodiment; for example, the shape of the recess 243 can be set to have a U-shaped cross-section. Furthermore, the inner surface 242a of the abutting member 240 is not limited to being inclined relative to the bottom surface 241a as illustrated in the second embodiment; for example, it can be provided in a manner that is perpendicular to the bottom surface 241a.

[0211] • The abutment member 240 is not limited to being bonded to the rib 238 with an adhesive as illustrated in the second embodiment. For example, the abutment member 240 and the substrate 230A can also be joined by hot pressing.

[0212] The bonding material included in the conductive material forming the contact member 240 is not limited to the epoxy resin exemplified in the second embodiment; for example, phenolic resin can also be used. Furthermore, the bonding material is not limited to thermosetting resins; thermoplastic resins such as polypropylene, polyamide, and polyphenylene sulfide can also be used.

[0213] • Alternatively, the abutment member 240 can be integrally formed relative to the rib 238 by embedding the substrate 230A into the molding die and injection molding.

[0214] • The substrate 230A of the separator 230 is not limited to being formed by stamping a metal component; for example, it can also be formed by cutting or etching.

[0215] • The material 230A used as the base material for the separator 230 is not limited to titanium or stainless steel, and aluminum or carbon can also be used.

[0216] The separator for fuel cells disclosed herein is not limited to the separator 230 shown in the second embodiment, which is connected to the anode electrode 211B side of the MEA210, but can also be applied to the separator 250 connected to the cathode electrode 211A side.

Claims

1. A separator for a fuel cell, comprising opposing surfaces arranged opposite to the power generation section of the fuel cell, wherein a plurality of channel paths for the flow of reactant gases are arranged on the opposing surfaces, wherein, Multiple ribs are provided on the opposite surfaces, located between the flow channels and protruding toward the power generation unit. At least one of the plurality of ribs is provided with at least one recess located at the center of the rib in the arrangement direction of the plurality of groove flow paths. The recess has: a bottom surface extending along the surface direction of the power generation part and opposite to the power generation part; and a pair of inner side surfaces rising from both ends of the bottom surface in the arrangement direction. The pair of inner surfaces are inclined such that they are closer to the power generation unit in the direction opposite to the power generation unit and further away from the bottom surface in the arrangement direction. The plurality of said slot flow paths include a first slot flow path and a second slot flow path that extend in a wavy manner in the surface direction of the opposite surfaces and are adjacent to each other in the arrangement direction. The plurality of ribs have wavy portions located between the first groove flow path and the second groove flow path. The wavy portion has a narrow section, which is narrower in width along the arrangement direction compared to other portions of the wavy portion. The at least one recess includes a recess provided in the narrow portion.

2. The separator for a fuel cell according to claim 1, wherein, The height from the bottom surface of the recess to the top of the rib is more than 10 μm and less than 30 μm. The angle of inclination of the pair of inner surfaces relative to the bottom surface is more than 1 degree and less than 5 degrees.

3. The separator for a fuel cell according to claim 1, wherein, The at least one recess includes a plurality of recesses located at multiple points on the opposite surface in the direction of extension of the rib.

4. The separator for a fuel cell according to claim 1, wherein, The at least one recess is provided in each of the plurality of ribs.

5. The separator for a fuel cell according to any one of claims 1 to 4, wherein, The power generation unit is held by a frame member located on the outer periphery of the power generation unit. When the opposing surfaces are considered as inner opposing surfaces The separator for the fuel cell has an outer opposing surface opposite to the frame member. Each of the plurality of said channel flow paths and the plurality of said ribs has a protrusion extending outward toward the opposite outer surface. The at least one recess includes a recess provided in the protrusion of the rib.

6. A single cell of a fuel cell, wherein, The single cell of this fuel cell has the following features: A pair of partitions; and The power generation unit is held between the pair of partitions and has a pair of gas diffusion layers that respectively abut against the pair of partitions. At least one of the pair of separators is a separator as described in any one of claims 1 to 5. The power generation unit sinks into the recess.

7. A separator for a fuel cell, having opposing surfaces arranged opposite to the power generation section of the fuel cell, wherein a plurality of channel paths for the flow of reactant gases are arranged on the opposing surfaces, wherein... The separator used in this fuel cell has the following features: The substrate has the plurality of channel flow paths and a plurality of ribs located between the channel flow paths and protruding toward the power generation section; as well as The abutting member abuts against the power generation unit. The abutment member engages with one of the plurality of ribs. The abutment member has: The base, which engages with the rib; and A pair of protrusions, which protrude from the base and are spaced apart from each other in the arrangement direction of the plurality of channel flow paths, The plurality of said slot flow paths include a first slot flow path and a second slot flow path that extend in a wavy manner in the surface direction of the opposite surfaces and are adjacent to each other in the arrangement direction. The plurality of ribs have wavy portions located between the first groove flow path and the second groove flow path. The wavy portion has a narrow section, which is narrower in width along the arrangement direction compared to other portions of the wavy portion. The recesses formed between the protrusions include the recesses provided in the narrow portion.

8. The separator for a fuel cell according to claim 7, wherein, The base has a bottom surface that extends between the protrusions along the surface direction of the power-generating portion and is opposite to the power-generating portion. The pair of protrusions have inner surfaces that stand upright from the ends in the arrangement direction of the bottom surface. The inner surface is inclined such that it is closer to the power generation unit in the direction opposite to the power generation unit and further away from the bottom surface in the arrangement direction.

9. The separator for a fuel cell according to claim 8, wherein, The height from the bottom surface of the base to the top of the pair of protrusions is more than 10 μm and less than 30 μm. The angle of inclination of the pair of inner surfaces relative to the bottom surface is more than 1 degree and less than 5 degrees.

10. The separator for a fuel cell according to claim 7, wherein, The abutting member is disposed on the opposite surface along the entire extension direction of the rib.

11. The separator for a fuel cell according to claim 7, wherein, The abutting member is provided on each of the plurality of ribs.

12. The separator for a fuel cell according to any one of claims 7 to 11, wherein, The power generation unit is held by a frame member located on the outer periphery of the power generation unit. When the opposing surfaces are considered as inner opposing surfaces The separator for the fuel cell has an outer opposing surface opposite to the frame member. Each of the plurality of said channel flow paths and the plurality of said ribs has a protrusion extending outward toward the opposite outer surface. The abutting member is also provided at the protrusion of the rib.

13. A single cell of a fuel cell, wherein, The single cell of this fuel cell has the following features: A pair of partitions; and The power generation unit is held between the pair of partitions and has a pair of gas diffusion layers that respectively abut against the pair of partitions. At least one of the pair of separators is the separator according to any one of claims 7 to 12. The power generation unit sinks into the portion of the base located between the protrusions.

Images