Punching die

Abstract

In a unit of a fuel cell stack, there is a problem of poor adhesion of a separator to a resin frame. A press die for manufacturing a unit of a fuel cell stack, the unit including a membrane electrode assembly, a frame holding the membrane electrode assembly, and a separator, the frame and the separator being adhered by an adhesive, the press die being used to adhere the separator, the adhesive, and the frame by pressing the separator, the adhesive, and the frame in a heated state, the press die including a press surface that, when pressed, contacts the separator and is located at an edge portion of the frame when the separator and the frame are viewed in a direction in which the separator and the frame overlap, the press surface including a groove portion that, when the separator and the frame are viewed in the direction of pressing, extends along the edge portion of the frame and is located at at least a portion of the edge portion of the frame.

Description

Technical Field

[0001] This invention relates to a stamping die. Background Technology

[0002] As shown in Patent Document 1, in the manufacturing of a fuel cell stack unit, the separator is bonded to a resin frame while being heated and pressurized through a mold. Furthermore, a thermoplastic adhesive is used in this bonding process.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2021-141005 Summary of the Invention

[0004] Due to limitations in machining precision, minute irregularities can sometimes occur on the surface of the mold used when pressurizing the partition. Furthermore, thermal expansion caused by heating during pressurization can also deform the mold surface, sometimes resulting in irregularities.

[0005] During pressurization, air inside the adhesive or at the interface between the partition and the adhesive may not be completely expelled. In particular, when there are depressions on the mold surface, air in the portion of the partition facing the depression is more difficult to pressurize than in other portions, making it even harder to expel. This unexpelled air remains as air bubbles, hindering the tight adhesion between the partition and the adhesive. Therefore, poor adhesion between the partition and the resin frame becomes a problem.

[0006] The present invention can be implemented in the following ways.

[0007] (1) According to one aspect of the present invention, a stamping die is provided for manufacturing a unit of a fuel cell stack. In the stamping die, the unit includes: a membrane electrode assembly; a frame that holds the membrane electrode assembly; and a separator that is arranged to overlap with the membrane electrode assembly held in the frame and the frame, the frame and the separator being bonded by an adhesive, the stamping die being used to bond the separator, the adhesive and the frame by applying pressure to the separator, the adhesive and the frame in a heated state, the stamping die including: a stamping surface that contacts the separator when pressure is applied and is located at the edge of the frame when the separator and the frame are viewed in the direction of overlap of the separator and the frame, i.e., the pressure direction, the stamping surface including: one or more grooves that extend along the edge of the frame and are located at at least a portion of the edge of the frame when the separator and the frame are viewed in the pressure direction. In this method, the portion of the partition facing the groove bulges relatively due to the strong pressure applied around it. This increases the contact area between the partition and the adhesive, thus suppressing poor adhesion. Therefore, compared to a stamping die with a flat stamping surface, the stamping die can suppress the occurrence of poor adhesion between the partition and the frame.

[0008] (2) In the stamping die described above, the fuel cell stack has multiple units stacked along the pressurization direction. In the stacked state, the stamping die receives pressure in the pressurization direction. The partition and the frame each further include: a manifold opening that opens in the pressurization direction and is arranged to overlap each other when viewed along the pressurization direction. Each unit also includes: a gasket that is arranged on the partition between each of the multiple units in the stacked state and is disposed on a first portion including a portion of the edge of the manifold opening. The gasket receives pressure in the pressurization direction in the stacked state. The one or more slots, when viewed along the pressurization direction, can be arranged as a second portion of the edge of the manifold opening, which is part of the edge of the manifold opening other than the first portion. In this manner, the gasket receives pressure in the stacked state. Thus, the first portion of the partition with the gasket receives this pressure. On the other hand, the second part without the gasket is less able to withstand the pressure. That is, the second part without the gasket is more likely to peel off the partition from the frame than the first part with the gasket. However, by positioning the groove in the second part, the stamping die can suppress poor adhesion in the second part.

[0009] (3) In the stamping die of the above manner, the more than one groove can be constituted by one. By setting it in this way, when there is only one groove, the pressure applied to the partition may be difficult to distribute compared to the case of two or more grooves. Therefore, compared to the case where there are two or more grooves, the stamping die can sometimes suppress poor adhesion between the partition and the frame. Attached Figure Description

[0010] Figure 1 This is a three-dimensional diagram showing the general structure of a fuel cell stack.

[0011] Figure 2 This is an explanatory diagram showing the unit in its exploded form.

[0012] Figure 3 This is an explanatory diagram showing the range of pressure applied through the stamping surface in the partition.

[0013] Figure 4 It is shown Figure 3 A sectional view of section IV-IV.

[0014] Figure 5 This is a process diagram illustrating the manufacturing method of a fuel cell unit.

[0015] Figure 6 It is magnification Figure 4 A cross-sectional view of the adhesive portion under pressure.

[0016] Figure 7 This is an explanatory diagram showing the stamping die of the second embodiment. Detailed Implementation

[0017] A. Implementation Method 1:

[0018] A-1. Structure of a fuel cell unit:

[0019] Figure 1 This is a perspective view showing the schematic structure of the fuel cell stack 1. The fuel cell of this embodiment is a solid polymer type fuel cell that generates electricity by accepting hydrogen and oxygen as reactant gases. The fuel cell stack 1 of the fuel cell is constructed by stacking multiple units 10.

[0020] exist Figure 1 In order to illustrate the structure of fuel cell stack 1, an orthogonal XYZ coordinate system was defined. Figure 1In this diagram, the X-axis direction is along the long side of unit 10. The Y-axis direction is along the short side of unit 10. The Z-axis direction is the thickness direction of unit 10 and the direction of the stacked units 10. That is, the Z-axis direction is the direction in which the frame 130 and the partition plate 120 overlap. In addition, the +Z direction in the Z-axis direction is also the direction in which unit 10 receives pressure from the stamping die 20 during the manufacturing of unit 10. The +Z direction is also the direction in which multiple units 10 receive pressure to form the fuel cell stack 1. Hereinafter, the +Z direction will be referred to as the "pressurization direction Dp".

[0021] That is, the fuel cell stack 1 has multiple units 10 stacked in the pressurization direction Dp. Moreover, the fuel cell stack 1 is configured to receive pressure in the pressurization direction Dp in the stacked state. Specifically, the fuel cell stack 1 is configured to receive pressure in the pressurization direction Dp by fastening it in the pressurization direction Dp by fastening members (not shown).

[0022] Figure 2 This is an exploded view of unit 10. Unit 10 includes a membrane electrode assembly (MEA) 110, a frame 130, a separator 120, and a gasket 140. The frame 130 is also referred to as "resin sheet 130". Furthermore, in the actual unit 10, the membrane electrode assembly 110, the frame 130, and the separator 120 overlap in a consistent manner. However, in... Figure 2 In order to facilitate understanding of the technology, the diagram illustrates how to use it. Figure 1 The state of positional offset of each structure on the XY plane.

[0023] Membrane electrode assembly 110 (reference) Figure 2 The middle section (central portion) includes: an electrolyte membrane; a cathode electrode formed on one surface of the electrolyte membrane; an anode electrode formed on the other surface of the electrolyte membrane; a gas diffusion layer formed on the side of the cathode electrode that is not in contact with the electrolyte membrane; and a gas diffusion layer formed on the side of the anode electrode that is not in contact with the electrolyte membrane. Additionally, in Figure 2 The diagrams of the constituent components are omitted. The electrolyte membrane is, for example, an ion-exchange membrane made of fluorinated resin. The anode electrode is the electrode on the side supplied with anolyte gas. The cathode electrode is the electrode on the side supplied with cathode gas. Both the anode and cathode electrodes are, for example, made of a carbon support carrying a platinum catalyst. The gas diffusion layer is, for example, made of carbon cloth. Furthermore, the anode gas is hydrogen. The cathode gas is air.

[0024] The partition 120 is a conductive component that forms a flow path for the anolyte gas or the cathode gas. The partition 120 consists of a first partition 121 (see reference 121). Figure 2 (the upper section) and the second partition 122 (refer to) Figure 2The lower section is constructed. The first partition 121 forms the flow path for the anode gas. The second partition 122 forms the flow path for the cathode gas. The partition 120 is formed, for example, from a dense carbon component made of compressed carbon to prevent gas from passing through. Furthermore, in Figure 2 The diagram omits the irregular shapes formed on the surface of the partition 120 to create flow paths for the reactant gas or coolant.

[0025] The partition 120 is a rectangular plate-shaped component. The shape of the partition 120 is the same as that of the frame 130. Thus, the partition 120 can clamp the membrane electrode assembly 110 held by the frame 130 between the first partition 121 and the second partition 122. That is, the partition 120 is arranged in a manner that overlaps with the membrane electrode assembly 110 held by the frame 130 and with the frame 130.

[0026] Frame 130 (Reference) Figure 2 The membrane electrode assembly 110 is held in the middle section of the frame 130. More specifically, the frame 130 is a rectangular frame with a central opening 131. Hereinafter, the portion constituting the frame 130 will be referred to as the "edge portion". The membrane electrode assembly 110 is held in the central opening 131 of the frame 130. The frame 130 is made of, for example, a thermoplastic resin. More specifically, polyethylene terephthalate (PET) is used as the material constituting the frame 130. Various other thermoplastic resins such as polypropylene and polyethylene may also be used.

[0027] In the state constituting unit 10, the frame 130 and the partition 120 are bonded together by a thermoplastic adhesive Ad. Adhesive Ad is, for example, thermoplastic polypropylene (PP). Alternatively, adhesive Ad can be ethylene propylene rubber. Furthermore, "bonding of partition 120 to frame 130" refers to the state where, by applying pressure to partition 120, adhesive Ad, and frame 130 under heating, the adhesive Ad undergoes a chemical reaction between the surface of frame 130 and the surface of partition 120, forming hydrogen bonds or covalent bonds, thereby binding frame 130 and partition 120 together.

[0028] The partition 120 and the frame 130 each have a manifold orifice M that opens in the pressurization direction Dp. The manifold orifice M is a through-hole that allows gas or cooling water to flow between the multiple units 10 constituting the fuel cell stack 1. That is, the respective manifold orifices M of the partition 120 and the frame 130 are arranged in an overlapping manner when viewed along the pressurization direction Dp. Thus, the manifold orifices M form a flow path by connecting in the pressurization direction Dp. The manifold orifices M are further classified into a first manifold orifice M1h, a second manifold orifice M2o, and a third manifold orifice M3w.

[0029] The first manifold M1h allows anolyte gas to flow within the membrane electrode assembly 110. That is, the first manifold M1h supplies and discharges anolyte gas into and out of the membrane electrode assembly 110. The second manifold M2o allows cathodic gas to flow within the membrane electrode assembly 110. That is, the second manifold M2o supplies and discharges cathodic gas into and out of the membrane electrode assembly 110. The third manifold M3w allows cooling water to flow within the partitions 120. That is, the third manifold M3w supplies and discharges cooling water between the partitions 120 in each unit 10.

[0030] Various manifold orifices are respectively configured as a pair for supply and discharge at the periphery of the partition 120 and the frame 130. For example, in Figure 2 In the first partition 121, one of the left and right first manifold holes M1h is a manifold hole M for supplying anode gas, and the other is a manifold hole M for discharging gas. The supply manifold hole M and the discharging manifold hole M are also included in the second manifold hole M2o and the third manifold hole M3w. Gas or cooling water passes through the corresponding flow path within the unit 10 via the supply manifold hole M and the discharging manifold hole M.

[0031] The gasket 140 has the function of sealing the space between two adjacent units 10 by clamping the surfaces of two adjacent units 10 when multiple units 10 are stacked. Therefore, the gasket 140 is made of an elastic component such as rubber or resin.

[0032] The gasket 140 is disposed on the partition 120 such that it is located between each of the multiple units 10 in a stacked state. More specifically, the gasket 140 is disposed on the surface of the first partition 121 opposite to the surface facing the frame 130. Furthermore, the gasket 140 is disposed along the edge of the manifold hole M in a first portion 120p1 including a portion of the edge of the manifold hole M. More specifically, the gasket 140 is disposed around the periphery of each of the first manifold hole M1h and the second manifold hole M2o. Moreover, the gasket 140 is disposed in the edge of the third manifold hole M3w, except for a portion on the side facing the center of the partition 120. This other portion, excluding the first portion 120p1 in the edge of the manifold hole M in the partition 120, is referred to as the "second portion 120p2". Figure 2 In the diagram, part 2, 120p2, is the portion enclosed by the dashed line. The gasket 140, in a state where multiple units 10 are stacked, prevents gas flowing in the manifold orifice M from leaking between the stacked units 10 by receiving pressure in the pressurization direction Dp.

[0033] A-2. Structure of stamping die 20:

[0034] The stamping die 20 is used to manufacture the unit 10 of the fuel cell stack 1. More specifically, the stamping die 20 is used to bond the separator 120, adhesive Ad, and frame 130 by pressing them under heat. For example, the stamping die 20 is heated by a heater, and the separator 120, adhesive Ad, and frame 130 are pressed under heat. Therefore, a metal material with a low coefficient of thermal expansion and high durability is used in the stamping die 20. For example, stainless steel is used in the stamping die 20.

[0035] Figure 3 This is an explanatory diagram showing the range of pressure applied through the stamping surface 21 in the partition 120. Figure 3 The diagram illustrates the surface of the first partition 121 when viewed along the pressure direction Dp, where the unit 10 is disposed within the stamping die 20. The membrane electrode assembly range A110 represents the range of the membrane electrode assembly 110 located on the side opposite to the surface of the first partition 121 shown. The pressure range Ap, indicated by the shaded line, is the range within the surface of the first partition 121 other than the membrane electrode assembly range A110. That is, the pressure range Ap is the range along the edge of the frame 130.

[0036] The stamping die 20 includes a stamping surface 21. The stamping surface 21 is the surface of the stamping die 20 that contacts the partition 120 when pressure is applied. In this embodiment, the stamping surface 21 contacts the first partition 121 of the first partition 121 and the second partition 122 when pressure is applied. When pressure is applied, the stamping surface 21 is located at the edge of the frame 130 when viewing the partition 120 and the frame 130 along the pressure direction Dp, as shown in the pressure range Ap.

[0037] Figure 4 It is shown Figure 3 A sectional view of section IV-IV. Figure 4 To illustrate the positional relationship between the stamping die 20 and the partition 120, the stamping die 20 before pressurization is shown in the diagram. The stamping surface 21 has a groove 211. Specifically, the groove 211 is configured to extend along the edge of the frame 130 when viewed along the pressurization direction Dp, where the partition 120 and the frame 130 are disposed within the stamping die 20. Therefore, a cross-section perpendicular to the extending direction of the groove 211 is shown as follows. Figure 4 As shown.

[0038] The groove 211 is not located entirely on the edge of the frame 130, but only on a portion of the edge of the frame 130. More specifically, when viewing the partition 120 and the frame 130 disposed within the stamping die 20 along the pressing direction Dp, the groove 211 is located in the second part 120p2 of the edge of the manifold hole M in the partition 120 where the gasket 140 is not disposed (see reference). Figure 3 ).

[0039] Furthermore, the "1" in "1 groove 211" indicates the number of grooves arranged side by side. That is, it does not refer to the number of parts with grooves 211 in the entire stamping surface 21. In this embodiment, the groove 211 is located in the second part 120p2 at position 2, but the number of grooves in each part is 1.

[0040] like Figure 4 As shown, the groove 211, when viewed along its extension direction, is configured as a roughly quadrilateral gap. The depth D of the groove 211 is, for example, tens of μm. The width W of the groove 211 is, for example, several mm. The groove 211 is formed, for example, by laser processing. Alternatively, the groove 211 can also be formed by cutting.

[0041] A-3. Manufacturing method of fuel cell unit:

[0042] Figure 5 This is a process diagram illustrating the manufacturing method of cell 10 of the fuel cell. The manufacturing method of cell 10 will be described below. In the following description, the operator is a human, but the operation can also be performed by a robot.

[0043] exist Figure 5 In step S100, the operator prepares the components of unit 10. More specifically, the operator prepares the membrane electrode assembly 110, frame 130, partition 120, and gasket 140. The prepared frame 130 is used to hold the membrane electrode assembly 110 in place. Furthermore, the prepared first partition 121 is configured with the gasket 140.

[0044] exist Figure 5 In step S200, the operator prepares the stamping die 20. That is, the operator installs the stamping die 20 onto the stamping machine.

[0045] exist Figure 5 In step S300, the operator places the components of unit 10 onto the stamping die 20. More specifically, with the frame 130 clamped by the first partition 121 and the second partition 122, the operator places the frame 130 and the partition 120 onto the stamping die 20. Furthermore, with adhesive Ad applied between the frame 130 and the first partition 121 and between the frame 130 and the second partition 122, the operator places the partition 120 and the frame 130 onto the stamping die 20.

[0046] exist Figure 5 In step S400, the operator bonds the partition 120 and the frame 130. That is, while the stamping die 20 is heated, the operator applies pressure to the partition 120 through the stamping surface 21, thereby bonding the partition 120 and the frame 130.

[0047] Figure 6 It is magnification Figure 4 A cross-sectional view of the Ad portion of the adhesive under pressure. Figure 6 In, such as Figure 4 As shown, a cross-sectional view perpendicular to the extending direction of the groove 211 is illustrated. When pressure is applied by the stamping die 20, the portion 212 of the stamping surface 21 other than the groove 211 contacts the partition 120, thereby pressurizing the partition 120. Furthermore, through heating based on the stamping die 20, a chemical reaction occurs between the adhesive Ad and the frame 130 and the partition 120, thereby bonding the frame 130 and the partition 120.

[0048] Furthermore, in the groove 211, during pressurization, the portion 120p3 of the partition 120 facing the groove 211 experiences lower pressure than its surroundings. When the adhesive Ad, pressurized via the partition 120, contains air, the air moves from the high-pressure portion to the low-pressure portion due to pressurization. Therefore, the likelihood of air contained in the adhesive Ad near the portion 120p3 of the partition 120 facing the groove 211 moving to the surroundings is low. That is, more air remains in the portion 120p3 of the partition 120 facing the groove 211, making it easier for air bubbles to form. As a result, more air bubbles may form at the interface Ads between the partition 120 and the adhesive Ad. When air bubbles are located at this interface Ads, the contact area between the partition 120 and the adhesive Ad is reduced, thus making poor adhesion more likely. However, the adhesive Ad near the portion 120p3 of the partition 120 facing the groove 211 bulges relatively due to the strong pressure applied to its surroundings. As a result, the partition 120 facing the groove 211 expands, increasing its surface area. Therefore, air bubbles are more likely to form in this portion 120p3. On the other hand, the contact area between the partition 120 and the adhesive Ad increases. Thus, poor adhesion is suppressed. Furthermore, the area around this portion 120p3 is strongly pressurized, making it difficult for air to remain and thus reducing the likelihood of air bubble formation. In other words, poor adhesion is also suppressed around this portion 120p3.

[0049] Furthermore, the portion 120p3 of the partition 120 facing the groove 211 does not directly contact the stamping surface 21, and therefore is less susceptible to heating than other portions of the partition 120 that do contact the stamping surface 21. However, this portion 120p3 of the partition 120 facing the groove 211 is also heated by heat transferred from the surroundings. Therefore, the adhesive Ad located on this portion 120p3 also bonds the frame 130 and the partition 120.

[0050] exist Figure 5In step S500, the operator stacks and bonds multiple units 10 with partitions 120 and frames 130 together. Furthermore, the operator fastens the stacked units 10 in the pressurization direction Dp using fastening components. Thus, the manufacturing of the fuel cell stack 1 is completed.

[0051] In the first embodiment described above, the groove 211 is located along the edge of the frame 130 when pressurized. During pressurization, the portion 120p3 of the partition 120 facing the groove 211 experiences lower pressure than its surroundings. When the adhesive Ad, pressurized via the partition 120, contains air, the air moves from the high-pressure portion to the low-pressure portion due to pressurization. Therefore, the likelihood of air contained in the adhesive Ad near the portion 120p3 of the partition 120 facing the groove 211 moving to the surroundings is low. That is, more air remains in the portion 120p3 of the partition 120 facing the groove 211, making it easier for air bubbles to form. As a result, more air bubbles may form at the interface Ads between the partition 120 and the adhesive Ad. When air bubbles are located at this interface Ads, the contact area between the partition 120 and the adhesive Ad is reduced, thus making poor adhesion more likely. However, the portion 120p3 of the partition 120 facing the groove 211 bulges relatively due to the strong pressure applied to its surroundings. As a result, the partition 120 facing the groove 211 expands, increasing its surface area. Therefore, air bubbles are more likely to form in this portion 120p3. On the other hand, the contact area between the partition 120 and the adhesive Ad increases. This suppresses poor adhesion. Furthermore, the area around this portion 120p3 is strongly pressurized, making it less likely for air to remain and thus less prone to air bubble formation. In other words, poor adhesion is also less likely to occur. Therefore, compared to a stamping die 20 with a flat stamping surface 21, the stamping die 20 of this embodiment can suppress the occurrence of poor adhesion between the partition 120 and the frame 130.

[0052] Furthermore, in the first embodiment, the gasket 140 receives pressure while multiple units 10 are stacked. Therefore, the first portion 120p1 of the partition 120 where the gasket 140 is disposed receives this pressure. On the other hand, the second portion 120p2 without the gasket 140 is less able to withstand this pressure. That is, the second portion 120p2 without the gasket 140 is more likely to peel the partition 120 from the frame 130 than the first portion 120p1 with the gasket 140. However, the stamping die 20 of this embodiment, by positioning the groove 211 in the second portion 120p2, can suppress poor adhesion in the second portion 120p2.

[0053] Furthermore, in the first embodiment, the groove 211 is composed of only one portion. Therefore, when there is only one groove 211, the pressure applied to the partition 120 may be more difficult to distribute compared to when there are two or more grooves 211. That is, compared to when there are two or more grooves 211, the portion 120p3 of the partition 120 facing the groove 211 protrudes more significantly. Therefore, poor adhesion is more easily suppressed. Thus, compared to when there are two or more grooves 211, the stamping die 20 of this embodiment can sometimes suppress poor adhesion between the partition 120 and the frame 130.

[0054] B. Second Implementation Method:

[0055] Figure 7 This is an explanatory diagram showing the stamping die 20A according to the second embodiment. Figure 7 In the middle, in with Figure 6 The cross-sectional view of the same unit 10 illustrates the stamping die 20A of the second embodiment. In the above embodiment, there is one groove 211. However, there may be two or three grooves 211, as long as there is one or more. Furthermore, two or more grooves 211 may be arranged side-by-side and extend along the edge of the frame 130. For example, in two grooves 211, such as... Figure 7 As shown, in a cross section perpendicular to the extending direction of the groove 211, gaps are formed in an adjacent manner.

[0056] C. Other implementation methods:

[0057] (C1) In the above embodiment, the groove 211 is formed by a generally quadrilateral gap in a cross section perpendicular to the extending direction of the groove 211. However, the shape of the gap is not limited to a generally quadrilateral shape. The shape of the gap may be formed by a generally triangular or a generally semi-circular gap.

[0058] (C2) In the above embodiment, when viewed along the pressing direction Dp, the partition 120 and the frame 130 disposed within the stamping die 20 are located on a portion of the edge of the frame 130. However, the groove 211 may be located on the entire edge of the frame 130. That is, the groove 211 need only be located on at least a portion of the edge of the frame 130.

[0059] (C3) In the above embodiment, when viewed along the pressing direction Dp, the partition 120 and frame 130 disposed within the stamping die 20 are located in the second portion 120p2 where the gasket 140 is not disposed. However, the more than one groove 211 may also be located in the first portion 120p1 where the gasket 140 is disposed. More specifically, the more than one groove 211 may be located along the first portion 120p1 in a manner that does not overlap with the gasket 140.

[0060] (C4) In the above embodiment, the stamping surface 21 contacts the first partition 121 of the first partition 121 and the second partition 122 when pressurized. However, the stamping surface 21 may also contact the second partition 122 of the first partition 121 and the second partition 122 when pressurized. That is, the stamping die 20 can pressurize the partition 120 from the side of the second partition 122.

[0061] (C5) In the above embodiment, the gasket 140 is disposed on the first partition 121. However, the gasket 140 may also be disposed on the second partition 122 instead of the first partition 121.

[0062] This invention is not limited to the embodiments described above, and can be implemented in various structures without departing from its spirit. For example, in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects, the technical features of the embodiments corresponding to the technical features in the various methods described in the summary section of the invention can be appropriately replaced or combined. Furthermore, if such technical features are not required to be described in this specification, they can be appropriately omitted.

[0063] Symbol Explanation

[0064] 1-Fuel cell stack, 10-Unit, 20, 20A-Stamping die, 21-Stamping surface, 110-Membrane electrode assembly, 120-Separator, 120p1-Part 1, 120p2-Part 2, 121-First separator, 122-Second separator, 130-Frame, 131-Opening, 140-Gasket, 211-Groove, Ad-Adhesive, Ap-Pressure range, A110-Membrane electrode assembly range, Dp-Pressure direction, M-Manifold hole, M1h-First manifold hole, M2o-Second manifold hole, M3w-Third manifold hole.

Claims

1. A stamping die for manufacturing units of a fuel cell stack, characterized in that, The unit comprises: Membrane electrode assembly; A frame that holds the membrane electrode assembly; and A septum, which is configured to overlap with the membrane electrode assembly held in the frame and the frame itself. The frame and the partition are bonded together with adhesive. The stamping die is used to bond the partition, the adhesive, and the frame by applying pressure to them under a heated state. The stamping die includes a stamping surface that contacts the partition plate during pressurization and, when viewed along the direction of overlap between the partition plate and the frame (i.e., the pressurization direction), is located at the edge of the frame. The stamping surface includes: one or more grooves that, when viewed along the pressing direction, extend along the edge of the frame and are located at least a portion of the edge of the frame.

2. The stamping die according to claim 1, characterized in that, The fuel cell stack comprises multiple units stacked along the pressurization direction. In this stacked state, the fuel cell receives pressure from the pressurization direction through the stamping die. The partition and the frame each further include a manifold opening in the pressurization direction, and are arranged to overlap each other when viewed along the pressurization direction. The unit further comprises: a gasket, which, in the stacked state, is disposed on the partition in such a manner as to be located between each of the plurality of units, and is disposed on a first portion including a portion of the edge portion of the manifold orifice. The gasket receives pressure in the direction of pressure application in the stacked state. When viewed along the pressurization direction, the one or more slots disposed within the stamping die and the partition plate are arranged as a second part located in the edge portion of the manifold hole, which is part of the edge portion of the manifold hole other than the first part.

3. The stamping die according to claim 2, characterized in that, The more than one groove is composed of one.

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