Fuel cell and method for manufacturing a fuel cell.

Abstract

The present invention provides a fuel cell and a method for manufacturing a fuel cell that can prevent fastening bolts from loosening due to expansion and contraction caused by temperature changes, even when fastening dissimilar materials. [Solution] The wet-side end unit 30 is provided with a wet-side end plate 31 that presses a cell stack 10, which consists of multiple power generation cells 14 of the power generation unit 11, in the stacking direction. The wet-side end unit 30 has a frame-shaped reinforcing portion 34 along the outer circumference of a terminal plate 32 having a current collector 33 positioned corresponding to the power generation unit 11, and a plurality of fastening bolts 50 that fasten the frame-shaped reinforcing portion 34 to an insulator 35 provided on the wet-side end plate 31 side of the current collector 33. Adhesive is applied to at least one of the fastening bolts 50.

Description

Technical Field

[0001] The present invention relates to a fuel cell and a method for manufacturing a fuel cell.

Background Art

[0002] Conventionally, a gas seal structure provided with a ridge portion that is fitted into a joint surface to ensure airtightness between a metal member having a through screw hole and the head of a bolt screwed into the screw hole is known (for example, Patent Document 1). In such a structure, a ridge is provided on the seating surface of the head of the bolt and is bitten into the substrate, so that gas sealing performance is maintained without using a gasket or washer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, end units provided at both ends of a stacked cell of a fuel cell are generally composed of different materials, including a terminal plate or an end plate which is a metal plate and a resin insulator (insulator), and are fastened to each other with fastening bolts. In the prior art, when fastening different materials such as each plate and insulator serving as reinforcing members using a fastening bolt, the coefficient of thermal expansion is different for each material. Therefore, there is a risk of cracks occurring starting from the ridge portion into which the fastening bolt is bitten. In addition, such a stacked cell of a fuel cell is compression-fixed, and it is known that the power generation part becomes high temperature during power generation. Therefore, each component of the end unit may repeatedly expand and contract due to the temperature difference between the start-up and stop of the fuel cell, resulting in looseness in the fastening bolt. In particular, fuel cells are composed of different materials and have a difference in the coefficient of thermal expansion, making them even more likely to loosen. If cracks or loose fastening bolts occur, fuel gas or air from the fuel cell may leak, potentially resulting in insufficient power generation performance, or water may enter the power generation section, leading to unstable power generation. There was room for further improvement. The purpose of this invention is to provide a fuel cell and a method for manufacturing a fuel cell that can prevent fastening bolts from loosening due to expansion and contraction caused by temperature, even when fastening dissimilar materials. [Means for solving the problem]

[0005] To solve the aforementioned problems, the fuel cell of the present invention comprises a cell stack comprising a plurality of power generation cells having a membrane electrode structure and a separator, which are stacked to form a power generation section, and end units provided at both ends of the cell stack. The end units have an end plate that presses the cell stack in the stacking direction and a terminal plate that collects power from the power generation section. The terminal plate has a current collector positioned at a location corresponding to the power generation section and a frame-shaped reinforcing section provided in a frame shape along the outer circumference of the current collector. The terminal plate also has an insulator provided on the end plate side of the current collector and a plurality of fastening bolts that fasten the frame-shaped reinforcing section to the insulator. Furthermore, at least one of the plurality of fastening sections that fasten the frame-shaped reinforcing section to the insulator with the fastening bolts is coated with adhesive. [Effects of the Invention]

[0006] According to the present invention, a fuel cell and a method for manufacturing a fuel cell are provided that can prevent fastening bolts from loosening due to expansion and contraction caused by temperature, even when fastening dissimilar materials. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view showing the overall configuration of a fuel cell according to an embodiment of the present invention. [Figure 2] This is a perspective view illustrating the configuration of the end unit. [Figure 3]This is a simplified cross-sectional view of the fastening portion of the embodiment, taken along line III-III in Figure 1. [Figure 4] This is a plan view of the terminal plate as seen from the cell stack side. [Figure 5] This is a cross-sectional view illustrating the assembly sequence of the end unit. [Modes for carrying out the invention]

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. The same reference numerals will be used for identical components, and redundant explanations will be omitted. For convenience, as shown in the figure, among the three mutually orthogonal axis directions, the cell stacking direction will be defined as the front-to-back stacking direction X, the left-to-right direction Y, and the up-to-down direction Z, and the configuration of each part will be described according to this definition. These directions do not necessarily coincide with, for example, the front-to-back direction of a vehicle when a fuel cell is mounted on the vehicle.

[0009] First, we will explain the overall configuration of the fuel cell 100 using Figure 1. The fuel cell 100 comprises a cell stack 10, a case 20 that surrounds and houses the cell stack 10, and a pair of wet-side end units 30 and dry-side end units 40 positioned at both ends of the case 20 to press the cell stack 10 in the stacking direction X, and the whole has a rectangular parallelepiped shape. Of these, the cell stack 10, which constitutes the main part of the stack structure, has multiple power generation cells 14, each having a membrane electrode structure 12 and a separator 13, stacked to form a power generation section 11. Multiple manifolds communicating in the stacking direction X are formed around the power generation section 11 of the cell stack 10.

[0010] Furthermore, the case 20 has four substantially rectangular side walls that face the top, right, bottom, and left sides of the cell stack 10, respectively. The case 20 is made of a metal material such as aluminum or iron. When these four side walls are connected, a substantially box-shaped storage space is formed that opens the dry end opening 22 and the wet end opening 21 at the rear.

[0011] Furthermore, the fuel cell 100 of this embodiment has a wet-side end unit 30 and a dry-side end unit 40 as end units on both sides of the cell stack 10. Of these, the wet-side end unit 30 mainly comprises a wet-side end plate 31 that closes one end of the case 20, and a terminal plate 32 that is positioned between the wet-side end plate 31 and the cell laminate 10.

[0012] Furthermore, the dry-side end unit 40 includes a dry-side end plate 41 that closes the other end of the case 20, and a terminal plate 42, etc., which is positioned between the dry-side end plate 41 and the cell laminate 10. Then, the metal wet-side end plate 31 and dry-side end plate 41 of the wet-side end unit 30 shown in Figure 1 are attached to the wet-side end opening 21 and dry-side end opening 22 of the case 20, respectively, using multiple screw members (not shown), with annular sealing members 38 interposed between them. As a result, the wet-side end plate 31 and the dry-side end plate 41 press both end faces of the cell stack 10 in the housing space from both sides of the case 20 toward the inside in the stacking direction X.

[0013] For example, a terminal plate 32 (see Figure 2) is provided between the wet-side end plate 31 and the cell laminate 10 on the inside. The wet-side end plate 31 presses the flat terminal plate 32 from the outside to the inside via a plurality of sealing members 37. As a result, the cell laminate 10 provided on the inside of the terminal plate 32 is pressed between the membrane electrode structure 12 and the separator 13, and is sandwiched between the wet-side end unit 30 and the dry-side end unit 40 provided on both ends in the lamination direction X, and fixed in the storage space of the case 20.

[0014] Next, here, the configuration of the wet-side end unit 30 among the end units of the embodiment will be described. Note that the dry-side end unit 40 is configured in the same manner as the wet-side end unit 30, except for the shape of the dry-side end plate 41 that closes the case closing end, the inner insulator 35, and the terminal plate 42. Therefore, the description of the configuration of the dry-side end unit 40 will be omitted.

[0015] Also, a terminal plate 32 (see FIG. 2) is provided between the wet-side end plate 31 and the cell stack 10 inside the wet-side end plate 31. The wet-side end plate 31 presses the flat terminal plate 32 from the outside toward the inside via a plurality of seal members 37. As a result, the cell stack 10 provided inside the terminal plate 32 is sandwiched by the wet-side end unit 30 and the dry-side end unit 40 provided at both ends in the stacking direction X and is fixed in the storage space of the case 20.

[0016] As shown in FIG. 2, the terminal plate 32 provided in the wet-side end unit 30 of the embodiment includes a current collector 33 that collects the power generated in the power generation unit 11, a frame-shaped reinforcing portion 34, an insulator 35 made of resin as an insulator, and a plurality of fastening bolts 50 that fasten the frame-shaped reinforcing portion 34 to the insulator 35. Among these, the current collector 33 has its inner surface 33c in contact with the side surface 13a of the separator 13 located on both end faces in the stacking direction X of the cell stack 10 (see FIG. 3). The current collector 33 also connects a metal L-shaped terminal 36. The power generated in the power generation unit 11 is configured to be collected by the current collector 33 and output to the outside of the case 20 via the terminal 36.

[0017] Further, the frame-shaped reinforcing portion 34 of the embodiment is made of a metal such as stainless steel (SUS) and is provided in a frame shape along the outer periphery of the terminal plate 32. And, between the frame-shaped reinforcing portion 34 of the terminal plate 32 and the cell stack 10, a sealing material 15 (see FIG. 3) for sealing around the manifold opening formed in the cell stack 10 and the like is provided. The sealing material 15 is pre-coated on the side surface 13a of the separator 13. The sealing material 15 can be cured after coating to provide a desired interval between the frame-shaped reinforcing portion 34 and the cell stack 10.

[0018] Furthermore, as shown in FIG. 2, the wet-side end unit 30 has a resin insulator 35 as an insulator on the wet-side end plate 31 side of the current collector 33. A plurality of manifold openings are formed in the insulator 35 and are provided over substantially the entire surface of the terminal plate 32. And, as shown in FIG. 1, between the insulator 35 and the wet-side end plate 31, a plurality of seal members 37 for sealing around the manifold opening are provided. Thus, the insulator 35 is interposed between the current collector 33 of the terminal plate 32 and the wet-side end plate 31, and insulation is provided between the energized portions such as the current collector 33 and the case 20.

[0019] Also, as shown in FIG. 4, the frame-shaped reinforcing portion 34 of the embodiment is composed of a flat plate material. The frame-shaped reinforcing portion 34呈口字状 in a plan view so as to surround the central opening portion 34e where the current collector 33 is disposed. Furthermore, the frame-shaped reinforcing portion 34 of the embodiment is disposed outside the outer edge portion 33b of the current collector 33 in a plan view and inside along the outer peripheral edge of the terminal plate 32 and has a predetermined width. And, in the frame-shaped reinforcing portion 34, a plurality of communication openings 34a respectively corresponding to the manifold openings formed in the side surface 13a of the separator 13 are formed. The communication openings 34a are formed at positions corresponding to the manifold communication holes provided in the cell stack 10 and the insulator 35 and are communicated.

[0020] Around the communication opening 34a, a gasket 16 is provided on the insulator 35 side, corresponding to the position of the sealing material 15 on the separator 13 side (see Figure 3). The gasket 16 is made of rubber and is fitted into a recessed groove 35a formed in the insulator 35. The gasket 16 is then pressed against the frame-shaped reinforcing portion 34 and the insulator 35 to create a seal.

[0021] As shown in Figure 2, the terminal plate 32 has a plurality of insertion holes 32a through which the male threaded portions 51 of the fastening bolts 50 are each inserted. The insertion holes 32a are each inserted in the stacking direction X by the plurality of fastening bolts 50 that fix the frame-shaped reinforcing portion 34 to the insulator 35. In this embodiment, the insertion hole 32a corresponds in the stacking direction X to the bolt hole 34d formed through the frame-shaped reinforcing portion 34 and the boss portion 35b formed in recess at positions corresponding to each bolt hole 34d of the insulator 35. Of these, the bolt hole 34d, as shown in Figure 3, is sized to be larger than the outer diameter of the male threaded portion 51 of the fastening bolt 50 and smaller than the outer diameter of the head 52, allowing it to be freely inserted in the stacking direction X. Furthermore, a female threaded portion 35c is formed on the inner circumferential wall of the boss portion 35b, into which the male threaded portion 51 of the fastening bolt 50 is screwed.

[0022] Then, as shown in Figure 2, each fastening bolt 50 is inserted into the insertion hole 32a from the terminal plate 32 side, and the male threaded portion 51 at the tip is screwed into the female threaded portion 35c (see Figure 3) of the boss portion 35b. The back side of the head 52 of the fastening bolt 50 abuts against the opening edge of the bolt hole 34d, and the axial force generated between the head 52 and the male threaded portion 51 screwed into the female threaded portion 35c presses the frame-shaped reinforcing portion 34 against the insulator 35. Therefore, the fastening bolts 50 are fastened at multiple outer fastening parts 60, inner fastening parts 60a to 60h, and outer fastening parts 60i to 60t (hereinafter also referred to as fastening parts 60, etc.), and the frame-shaped reinforcing part 34 of the terminal plate 32 is attached to the insulator 35 (see Figure 4).

[0023] In the fuel cell 100 of the present invention, adhesive 70 is applied to at least one of the fastening parts 60, etc. In this embodiment, as shown in Figure 3, adhesive 70 is applied to at least one of the male threaded portion 51 of the fastening bolt 50 or the female threaded portion 35c formed on the boss portion 35b of the insulator 35, in the area that is inserted into the boss portion 35b. This section describes a case in which adhesive 70 is applied to the portion of the male threaded portion 51 of the fastening bolt 50 that is inserted into the boss portion 35b. However, this is not the only case; adhesive 70 may also be applied to the female threaded portion 35c, or adhesive 70 may be applied to both the portion of the female threaded portion 35c that is inserted into the boss portion 35b and to the female threaded portion 35c itself.

[0024] Furthermore, in the fuel cell 100 of this embodiment, among the multiple fastening parts 60, as shown in Figure 4, adhesive 70 is not applied to the inner fastening parts 60a to 60h which are arranged on the inner peripheral edge 34b of the frame-shaped reinforcing part 34 along the outer edge 33b of the current collector 33 (see Figure 3).

[0025] Furthermore, adhesive 70 is applied to the multiple outer fastening parts 60 and outer fastening parts 60i to 60t shown in Figure 4, which are arranged circumferentially along the outer edge 34c of the frame-shaped reinforcing part 34 (see Figure 3). In other words, adhesive 70 is applied only to the outer fastening parts 60 and outer fastening parts 60i to 60t. The frame-shaped reinforcing portion 34 is fastened and fixed to the insulator 35 by fastening bolts 50 at the inner fastening portions 60a to 60h or the outer fastening portions 60i to 60t. As a result, the fastening bolts 50 fastened to the outer fastening portions 60i to 60t along the outer peripheral edge 34c of the frame-shaped reinforcing portion 34 are prevented from loosening by the applied adhesive 70. Therefore, the gasket 16 pressed between the frame-shaped reinforcing portion 34 and the insulator 35 can maintain a good sealing condition.

[0026] Next, the manufacturing method of the fuel cell according to the embodiment will be described using Figure 5. In the manufacturing method of the fuel cell 100 of the embodiment, adhesive 70 is applied in advance to the female screw portion 35c formed on the boss portion 35b of the insulator 35 of the wet-side end unit 30. In this case, adhesive 70 is not applied to the inner fastening portions 60a to 60h which are arranged on the inner peripheral edge 34b of the frame-shaped reinforcing portion 34 along the outer edge 33b of the current collector 33.

[0027] Then, the fastening bolt 50 is inserted into the bolt hole 34d of the frame-shaped reinforcing part 34 from the inside toward the outer boss portion 35b in the stacking direction X of the frame-shaped reinforcing part 34. The tip of the male threaded portion 51 of the fastening bolt 50 reaches the female threaded portion 35c of the insulator 35, and the male threaded portion 51 is screwed into the female threaded portion 35c. As a result, the fastening bolt 50 can fasten and attach the frame-shaped reinforcing portion 34 of the terminal plate 32 to the insulator 35.

[0028] In the manufacturing method of the fuel cell 100 of this embodiment, the fastening bolt 50 inserted from the frame-shaped reinforcing portion 34 side does not have adhesive 70 applied to the male threaded portion 51. Therefore, when inserting the fastening bolt 50 into the bolt hole 34d of the frame-shaped reinforcing portion 34, the risk of adhesive 70 adhering to the peripheral edge or inner wall surface of the bolt hole 34d can be eliminated.

[0029] Then, as shown in Figure 3, each fastening part 60, etc., is fastened with a fastening bolt 50. At this time, the gasket 16 fitted into the groove 35a of the insulator 35 is compressed and seals the space between the frame-shaped reinforcing part 34 and the insulator 35. Furthermore, as shown in Figure 1, when the wet-side end plate 31 is attached to the wet-side end unit 30, the sealing member 37 seals the space between the insulator 35 and the wet-side end plate 31. As a result, the area around each manifold opening is sealed by the sealing material 15 and the sealing member 37.

[0030] Meanwhile, liquid sealant 15 has been pre-applied to the side surface 13a of the separator 13 located on the terminal plate 32 side of the cell laminate 10 shown in Figure 3, and has begun to harden. Therefore, when the wet-side end unit 30 (see Figure 1) is attached to the wet-side end opening 21 of the case 20, the frame-shaped reinforcing portion 34 presses the cell laminate 10 in the stacking direction X via the sealing material 15, fixing it in place so that it does not move within the case 20.

[0031] However, the gasket 16 deteriorates due to the surrounding heat and sealing solution generated by the power generation unit 11, and the reaction force of the rubber constituting the gasket 16 may weaken. In such a state, the axial force of the fastening bolt 50 decreases. Furthermore, in vehicles to which the fuel cell 100 is applied, the load applied to the sealing material 15 may momentarily increase due to vibrations during driving.

[0032] For example, the liquid sealant 15 pre-applied to the side surface 13a of the separator 13 hardens, resulting in a greater elastic reaction force compared to the rubber gasket 16, making it less prone to crushing. Therefore, the load applied to the sealing material 15 from the cell laminate 10 can compress the gasket 16, causing a momentary decrease in the axial force of the fastening bolt 50. In such cases, there was a risk that the fastening bolt 50 would loosen, causing the head or other parts protruding inward in the laminate direction X to come into contact with the power generation unit 11.

[0033] In this embodiment, the fuel cell 100 can prevent the fastening bolts 50 from loosening due to expansion and contraction caused by temperature, even when fastening dissimilar materials. In particular, when the frame-shaped reinforcing portion 34 is fastened to the insulator 35 of the wet-side end plate 31, which constitutes the wet-side end unit 30, by the fastening portion 60, the gasket 16 is pressed against the frame-shaped reinforcing portion 34 and the insulator 35 and pushed into the groove portion 35a. Therefore, even if the gasket 16 deteriorates due to the effects of ambient heat from power generation and the sealing solution, causing a decrease in reaction force, the adhesive 70 applied to the fastening portion 60 prevents the fastening bolt 50 from loosening.

[0034] In this embodiment, adhesive 70 is applied to a plurality of outer fastening parts 60 and outer fastening parts 60i to 60t arranged circumferentially along the outer edge 34c of the frame-shaped reinforcing part 34 shown in Figure 4 (see Figure 3). As a result, the fastening bolts 50 fastened at the multiple outer fastening parts 60 and outer fastening parts 60i to 60t are fixed to the female threaded portion 35c of the insulator 35 with adhesive 70 so as not to loosen. Therefore, even if the amount of expansion or contraction due to temperature changes differs between the frame-shaped reinforcing part 34 fastened with the fastening bolts 50 and the insulator 35, the loosening of the fastening bolts 50 can be prevented.

[0035] Furthermore, as shown in Figure 4, adhesive 70 is not applied to the inner fastening portions 60a to 60h which are located on the inner peripheral edge 34b of the frame-shaped reinforcing portion 34 along the outer edge 33b of the current collector 33 (see Figure 3). Therefore, for example, when performing maintenance on the fastening bolt 50, the adhesive 70 will not peel off during the attachment and detachment process and enter the power generation unit 11.

[0036] Furthermore, as shown in Figure 4, for the outer fastening portions 60 and 60i to 60t, which are arranged circumferentially along the outer edge 34c of the frame-shaped reinforcing portion 34, the adhesive 70 is pre-applied only to the portion of the insulator 35 that is inserted into the boss portion 35b, as shown in Figure 3. Therefore, it is not necessary to apply adhesive 70 to the portion of the fastening bolt 50 that is not inserted into the insulator 35, for example, the portion that is inserted into the bolt hole 34d of the frame-shaped reinforcing part 34. Therefore, even when the fastening bolts 50 are removed and reattached during maintenance, the amount of adhesive 70 that peels off can be reduced, thus providing practically beneficial effects.

[0037] As described above, the fuel cell 100 of the present invention includes a cell stack 10 in which a plurality of power generation cells 14, each having a membrane electrode structure 12 and a separator 13, are stacked to form a power generation section 11. The fuel cell 100 also includes a wet-side end unit 30 and a dry-side end unit 40 on both sides of the cell stack 10. Furthermore, the wet-side end unit 30 includes a wet-side end plate 31 that presses the cell stack 10 in the stacking direction X, and a terminal plate 32 that collects power from the power generation unit 11.

[0038] Furthermore, the terminal plate 32 includes a current collector 33 positioned at a location corresponding to the power generation unit 11, a frame-shaped reinforcing portion 34 provided in a frame shape along the outer circumference of the current collector 33, and an insulator 35 provided on the wet-side end plate 31 of the current collector 33. Furthermore, the terminal plate 32 has a plurality of fastening bolts 50 for fastening the frame-shaped reinforcing portion 34 to the insulator 35. A feature is that at least one of the plurality of fastening portions 60 that fasten the frame-shaped reinforcing portion 34 to the insulator 35 with the fastening bolts 50 is coated with adhesive 70.

[0039] The fuel cell 100 of the present invention, configured in this way, can provide a stack structure that prevents the fastening bolts 50 from loosening due to expansion and contraction caused by temperature, even when fastening different materials together.

[0040] As shown in Figure 3, at least one of the multiple fastening points 60 that fasten the frame-shaped reinforcing part 34 to the insulator 35 is secured to the insulator 35 by adhesive 70, preventing the fastening bolt 50 from loosening and rotating. Therefore, even if the amount of expansion and contraction due to temperature changes differs between the fastening bolt 50 and the different materials fastened together, such as the frame-shaped reinforcing part 34 and the insulator 35, the loosening of the fastening bolt 50 can be prevented.

[0041] Furthermore, the multiple fastening parts 60, etc., include outer fastening parts 60 and outer fastening parts 60i to 60t provided along the outer peripheral edge 34c of the frame-shaped reinforcing part 34. In addition, the fastening parts 60, etc., include inner fastening parts 60a to 60h provided along the inner peripheral edge 34b of the frame-shaped reinforcing part 34. The adhesive 70 is not provided on the inner fastening parts 60a to 60h. Therefore, even when fastening bolts 50 are attached or detached at the inner fastening portions 60a to 60h along the outer edge 34c of the current collector 33 during fastening or maintenance, the adhesive 70 will not peel off. Consequently, the peeled-off adhesive 70 will not enter the power generation unit 11 and cause power generation instability.

[0042] Furthermore, as shown in Figure 3, at least one of the fastening bolts 50 to which adhesive 70 is applied at the fastening portion 60, etc., has adhesive 70 applied to the portion that is inserted into the insulator 35.

[0043] Therefore, the adhesive 70 can fix the portion of the fastening bolt 50 that is inserted into the insulator 35 to the insulator 35, preventing it from loosening and rotating. Furthermore, adhesive 70 does not need to be applied to the portion of the fastening bolt 50 that is not inserted into the insulator 35, for example, the portion that is inserted into the bolt hole 34d within the frame-shaped reinforcing portion 34. Therefore, the amount of adhesive 70 that peels off during maintenance does not increase, and the risk of causing power generation instability is further reduced.

[0044] The manufacturing method for the fuel cell 100 includes the steps of applying adhesive 70 to at least one of the male threaded portion 51 of the fastening bolt 50 and the female threaded portion 35c provided on the insulator 35, and the fastening step of inserting the fastening bolt 50 into the female threaded portion 35c from the frame-shaped reinforcing portion 34 side and fastening the frame-shaped reinforcing portion 34 to the insulator 35. Then, after applying adhesive 70 to the female threaded portion 35c formed on the insulator 35, the fastening bolt 50 is inserted into the female threaded portion 35c of the insulator 35 from the frame-shaped reinforcing portion 34 side, thereby fastening the frame-shaped reinforcing portion 34 to the insulator 35.

[0045] The manufacturing method for the fuel cell 100 of the present invention, configured in this way, can prevent the fastening bolts 50 from loosening due to expansion and contraction caused by temperature, even when fastening different materials together. More specifically, even if adhesive 70 is not applied to the fastening bolt 50 inserted from the frame-shaped reinforcement part 34 side, the adhesive 70 that has been pre-applied to the female threaded part 35c of the insulator 35 fixes the fastening bolt 50 in the female threaded part 35c of the insulator 35 and prevents it from rotating. Therefore, when inserting the fastening bolt 50 from the frame-shaped reinforcing part 34 side, the adhesive 70 does not adhere to the fastening bolt 50 or the frame-shaped reinforcing part 34 side and remain there, eliminating the risk of it peeling off later, thus providing practically beneficial effects.

[0046] The present invention is not limited to the embodiments described above, and various modifications are possible. The embodiments described above are illustrative examples provided to facilitate understanding of the present invention, and are not necessarily limited to those comprising all the configurations described. Furthermore, it is possible to replace parts of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add configurations from other embodiments to the configuration of one embodiment. In addition, it is possible to delete parts of the configuration of each embodiment, or to add or replace other configurations. Possible modifications to the above embodiments are as follows, for example.

[0047] In the fastening portion 60 of the embodiment, as shown in Figure 4, adhesive 70 is not applied to the portion arranged along the outer peripheral edge 34c of the current collector 33. Also, as shown in Figure 3, adhesive 70 is applied to at least one of the fastening bolts 50 to which adhesive 70 is applied in the fastening portion 60, in the portion that is inserted into the insulator 35. However, the present invention is not limited thereto. For example, adhesive 70 may be applied to the part arranged along the outer peripheral edge 34c of the current collector 33. Also, adhesive 70 may be applied to the fastening bolts 50 in the part corresponding to the frame-shaped reinforcing part 34, not limited to the part inserted into the insulator 35. In other words, it is sufficient that at least one of the fastening parts 60 that fasten the frame-shaped reinforcing part 34 to the insulator 35 is secured to the insulator 35 by adhesive 70, preventing it from loosening and rotating. Furthermore, the shape, quantity, and material of the fastening bolts 50 are not particularly limited. [Explanation of Symbols]

[0048] 10-cell stack 11 Power Generation Department 12 Membrane electrode structure 13 Separator 14 power cells 30 Wet side end unit (end unit) 31. Wet side end plate (end plate) 32 Terminal Plates 33 Current collector 34 Frame-shaped reinforcing section 50 fastening bolts 60 Fastening part 70 Adhesives 100 fuel cell

Claims

1. A cell laminate in which multiple power generation cells having membrane electrode structures and separators are stacked to form a power generation section, The cell laminate comprises end units provided at both ends, The aforementioned end unit is An end plate that presses the cell stack in the stacking direction, It has a terminal plate that collects power from the power generation unit, The aforementioned terminal plate is A current collector positioned at a location corresponding to the power generation unit, A frame-shaped reinforcing portion is provided in a frame shape along the outer circumference of the current collector, An insulator provided on the end plate side of the current collector, The insulator has a plurality of fastening bolts that fasten the frame-shaped reinforcing portion, A fuel cell characterized in that at least one of the plurality of fastening points that fasten the frame-shaped reinforcing portion to the insulator with the fastening bolts is coated with adhesive.

2. The plurality of fastening portions comprises outer fastening portions provided along the outer peripheral edge of the frame-shaped reinforcing portion and inner fastening portions provided along the inner peripheral edge of the frame-shaped reinforcing portion, The adhesive is not provided in the inner fastening portion. The fuel cell according to claim 1, characterized in that it is as described above.

3. The fuel cell according to claim 1 or 2, characterized in that at least one of the fastening bolts to which the adhesive is applied to the fastening portion has the adhesive applied to the portion that is inserted into the insulator.

4. A method for manufacturing a fuel cell according to claim 1, The steps include applying adhesive to at least one of the male threaded portion of the fastening bolt and the female threaded portion provided on the insulator, A fastening step of inserting the fastening bolt from the frame-shaped reinforcing portion side into the female thread portion to fasten the frame-shaped reinforcing portion to the insulator, A method for manufacturing a fuel cell, comprising the above.

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