JP2016115446A - Fuel cell stack and manufacturing method of fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent water or dust from being collected on a gas permeable membrane of a ventilation hole on a case.SOLUTION: A fuel cell stack A comprises: a fuel cell body 1 including a laminate 11 which is formed by stacking a plurality of fuel battery unit cells in a stacking direction S; and a case 2 which has four lateral walls 22a surrounding the fuel cell body along the stacking direction and at least one opening 22c, and which houses the fuel cell body. The four lateral walls include an upper lateral wall 22a1 which is arranged on the upper side when the fuel cell stack is mounted on a mobile body. The case comprises a ventilation part 4 formed on the upper lateral wall. The ventilation part comprises: an open hole 40 which is formed on the upper lateral wall and communicates the inside of the case to the outside; a cylindrical wall 41 which stands from the circumference of the open hole toward the outside; a plurality of ventilation holes 44 formed on the cylindrical wall; a gas permeable membrane 43 arranged to cover the plurality of ventilation holes; and a lid 42 fitted to the outer end of the cylindrical wall.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fuel cell stack and a method for manufacturing the fuel cell stack.

  A case main body that houses a fuel cell stack including a plurality of single fuel cell cells, a side wall of the case main body that becomes an upper side when the fuel cell stack is mounted on a moving body, that is, a ventilation hole that is formed upward on the upper side wall; A fuel cell stack case including a gas permeable membrane disposed so as to cover a ventilation hole and a protective member disposed so as to cover the gas permeable membrane is disclosed (for example, see Patent Document 1). As protective means, a mesh structure such as a metal mesh or nylon mesh or a porous material is cited.

  In the fuel cell stack, hydrogen gas that is fuel gas may leak to the outside. Therefore, when the fuel cell stack is accommodated in the fuel cell stack case, the hydrogen gas concentration in the fuel cell stack case may increase. Therefore, in Patent Document 1, a ventilation hole is provided in the upper side wall where light hydrogen gas easily diffuses, and the ventilation hole is sealed with a gas permeable membrane. As a result, even when hydrogen gas leaks from the fuel cell stack into the fuel cell stack case, the hydrogen gas diffuses to the outside through the gas permeable membrane from the ventilation hole, so the hydrogen gas concentration in the fuel cell stack case Is kept at a low concentration. Here, the gas permeable membrane of the ventilation hole prevents intrusion of water or dust into the stack case from the outside. However, if the ventilation hole is formed upward on the upper side wall, water or dust tends to accumulate on the gas permeable membrane, the gas permeable membrane may be clogged, and the performance of ventilating hydrogen gas may be deteriorated. Therefore, in Patent Document 1, a protective means is provided on the upper side of the gas permeable film so as to cover the gas permeable film.

JP 2005-149732 A

  Incidentally, the configuration of the fuel cell stack accommodated in the fuel cell stack case of Patent Document 1 is not specifically described in Patent Document 1, but there are a plurality of fuel cell main bodies including a plurality of fuel cell single cells. A fuel cell stack surrounded by plates can be considered. For example, when the fuel cell body is a rectangular parallelepiped, the six surfaces of the rectangular parallelepiped are covered with six plates. In this case, a gasket is inserted between the plates to ensure water tightness. On the other hand, the inventors of the present application prepare a box-shaped case instead of a plate, and the fuel cell main body is housed in the case, so that the manufacturing cost can be reduced and the productivity can be improved while improving the water tightness. I found out. In this case, since the water tightness of the fuel cell stack is high, it is not necessary to further accommodate the fuel cell stack in a fuel cell stack case as in Patent Document 1.

  However, in this case, hydrogen gas may leak from the fuel cell body, and the hydrogen gas may stay in the case outside the fuel cell body. In order to cope with this, the inventors examined the application of a structure for exhausting hydrogen gas from the fuel cell stack case as in Patent Document 1 to a case for housing the fuel cell main body. As a result, even when using a mesh structure such as a metal mesh or nylon mesh or a protective member made of a porous material, water and dust gradually pass through the protective member when viewed in detail. Found that water and dust could pass through. When water or dust passes through the protective member, water or dust accumulates on the gas permeable membrane, the gas permeable membrane may be clogged, and the performance of ventilating hydrogen gas may be deteriorated. A technique capable of exhausting hydrogen gas in the case without being affected by water or dust is desired.

  According to one aspect of the present invention, a fuel cell main body including a stacked body formed by stacking a plurality of fuel cell single cells along the stacking direction, and four surrounding the fuel cell main body along the stacking direction. A fuel cell stack having at least one side wall and a case in which the fuel cell main body is accommodated, wherein the four side walls are mounted on a movable body. An upper side wall disposed on the upper side, and the case includes a ventilation part formed on the upper side wall, and the ventilation part is formed on the upper side wall and communicates with the inside and the outside of the case A hole, a cylindrical wall portion erected from the periphery of the through hole to the outside of the case, a plurality of ventilation holes formed in the cylindrical wall portion, and the plurality of ventilation holes. Gas permeable membrane and outside of the cylindrical wall Fuel cell stack comprising a lid attached, to is provided.

  According to another aspect of the present invention, a fuel cell main body including a stack formed by stacking a plurality of fuel cell single cells along the stacking direction, and four surrounding the fuel cell main body along the stacking direction. A fuel cell stack having at least one side wall and a case in which the fuel cell main body is accommodated, wherein the four side walls are mounted on a movable body. An upper side wall disposed on the upper side, and the case includes a ventilation part formed on the upper side wall, and the ventilation part is formed on the upper side wall and communicates with the inside and the outside of the case A hole, a cylindrical wall portion erected from the periphery of the through hole to the outside of the case, a plurality of ventilation holes formed in the cylindrical wall portion, and the plurality of ventilation holes. Gas permeable membrane and outside of the cylindrical wall And a lid portion attached to the fuel cell stack, the first hole serving as the through hole, and the plurality of ventilation holes formed in a peripheral region of the first hole. A step of preparing a plate member having a plurality of second holes, and a surrounding region of the first hole are raised from the plate member by burring, and the cylindrical wall portion having the plurality of ventilation holes is provided. Forming the gas-permeable membrane so as to cover the plurality of ventilation holes in the cylindrical wall, and forming the plate material into a case having the four side walls and the at least one opening. There is provided a method for manufacturing a fuel cell stack, comprising a step of arranging and a step of attaching the lid to the outer end of the cylindrical wall.

  According to the present invention, hydrogen gas in the case can be exhausted without being affected by water or dust.

It is a perspective view of the structural example of a fuel cell stack. It is sectional drawing of the structural example of a fuel cell stack. It is sectional drawing of the structural example of a fuel cell stack. It is sectional drawing of the structural example of a ventilation part. It is the schematic explaining the effect | action of a ventilation part. It is the schematic explaining the effect | action of a ventilation part. It is the schematic explaining the effect | action of a ventilation part. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing which shows the manufacturing process of a fuel cell stack. It is sectional drawing of the structural example of the ventilation part of another Example. It is sectional drawing of the structural example of the ventilation part of another Example. It is sectional drawing of the structural example of the ventilation part of another Example.

  The fuel cell stack A according to the example will be described. FIG. 1 is a schematic perspective view of a configuration example of the fuel cell stack A. FIG. The fuel cell stack A includes a fuel cell main body 1 and a case 2 that accommodates the fuel cell main body 1. The case 2 is provided with a ventilation part 4 for ventilation in the case 2.

  2 and 3 are schematic cross-sectional views of configuration examples of the fuel cell stack A. FIG. 2 is an E2-E2 cross-sectional view of FIG. 1, and FIG. 3 is an E3-E3 cross-sectional view of FIG. The fuel cell body 1 is supplied with a fuel gas such as hydrogen gas and an oxidant gas such as air, and generates electric power through an electrochemical reaction. The fuel cell main body 1 includes a stacked body 11, a terminal plate 12, an end plate 14, and an insulating plate 13. The stacked body 11 is formed by stacking a plurality of fuel cell single cells along the stacking direction S. The terminal plate 12 is disposed at both ends of the stacked body 11 in the stacking direction S. The end plate 14 is disposed outside the terminal plate 12 in the stacking direction S. The insulating plate 13 is disposed between the terminal plate 12 and the end plate 14. The terminal plate 12, the end plate 14, and the insulating plate 13 each have a rectangular shape when viewed in a cross section perpendicular to the stacking direction S. At that time, the terminal plate 12 and the insulating plate 13 have substantially the same size. On the other hand, the end plate 14 is approximately the same size as or slightly larger than the terminal plate 12 and the insulating plate 13. The terminal plate 12 and the end plate 14 are made of a conductive material, and the insulating plate 13 is made of an electrically insulating material.

  The case 2 holds the fuel cell main body 1 in a compressed state via the buffer layer 3 and restrains the fuel cell main body 1. The case 2 includes a case main body 22 and a lid plate 21. The case main body 22 accommodates the fuel cell main body 1 therein. The case main body 22 is substantially a rectangular parallelepiped, has four side walls 22a and a bottom wall 22b surrounding the fuel cell main body 1 along the stacking direction S, and has an opening facing the bottom wall 22b. The width of the bottom surface inside the case body 22 is slightly larger than the cross section perpendicular to the stacking direction S of the fuel cell body 1. The length in the stacking direction S inside the case body 22, that is, the depth, is the same as or slightly longer than the length in the stacking direction S when the fuel cell body 1 is compressed in the stacking direction S. The lid plate 21 is a lid of the case body 22 and is fastened to the case body 22 with a fastening member (not shown) so as to close the opening of the case body 22. The case body 22 and the lid plate 21 are made of a metal such as stainless steel or aluminum. In the embodiment shown in FIGS. 2 and 3, the side wall 22a and the bottom wall 22b are substantially flat side walls. However, in another embodiment (not shown), at least one of the side wall 22a and the bottom wall 22b is partially or entirely. A side wall having a curved surface.

  The four side walls 22a of the case body 22 include an upper side wall 22a1 disposed on the upper side when the fuel cell stack A is mounted on a moving body such as a vehicle, a lower side wall 22a2 disposed on the lower side, and an upper side wall 22a1. And lateral side walls 22a3 and 22a4 connecting the lower side wall 22a2. The ventilation part 4 is formed in the upper side wall 22a1. The ventilation unit 4 communicates the inside and the outside of the case 2 so that a gas such as hydrogen gas or air flows but water does not flow. In the embodiment shown in FIG. 2, two ventilation parts 4 are arranged along the stacking direction S on the upper side wall 22 a 1. In another embodiment (not shown), one or three or more ventilation parts 4 are arranged at an arbitrary position on the upper side wall 22a1.

  When the fuel cell body 1 is accommodated in the case body 22, the opening is closed by the lid plate 21, and the case body 22 and the lid plate 21 are fastened by a fastening member, the fuel cell body 1 is separated from the lid plate 21. The bottom wall 22b of the case body 22 is pressed and restrained from both sides in the stacking direction S. As a result, the end plates 14 and 14 on both sides of the fuel cell main body 1 approach each other in the stacking direction S. Therefore, the stacked body 11, the terminal plate 12, the insulating plate 13, and the end plate 14 are in close contact with each other in the stacking direction S. At this time, a gap G having a distance D is formed between the outer peripheral surface 1a of the fuel cell main body 1 along the stacking direction S and the inner peripheral surface 2a of the side wall 22a of the case 2 facing the outer peripheral surface 1a. When the depth of the case body 22 is slightly longer than the length of the compressed fuel cell body 1 in the stacking direction S, the bolt is tightened from the outside of the bottom wall 22b of the case body 22 and protrudes from the inside of the bottom wall 22b. The bolts press the end plate 14 of the fuel cell body 1 to restrain the fuel cell body 1.

  The buffer layer 3 absorbs the impact applied to the fuel cell main body 1, suppresses the displacement of the fuel cell main body 1, electrically insulates the fuel cell main body 1 and the case 2, and changes the dimension changed by the external force to the original. It is a member having a restoring force to return to dimensions. The buffer layer 3 preferably further has a dilatant characteristic that exhibits fluidity at a slow input load, deforms slowly, behaves like a solid at an abrupt input load, and hardly deforms. The buffer layer 3 is disposed between the fuel cell body 1 and the case 2, that is, in the gap G. 2 and 3, the buffer layer 3 is provided from one end to the other end of the fuel cell body 1 along the stacking direction S when viewed in the stacking direction S (FIG. 2). When viewed in a direction perpendicular to S (FIG. 3), it is provided at least in the vicinity of the four corners Cn of the fuel cell body 1. Examples of the material of the buffer layer 3 include a mixture of a resin and a solid material such as a mixture of silicone oil and boric acid or a mixture of silicone resin and silica.

  The lid plate 21, the terminal plate 12, the insulating plate 13, and the end plate 14 positioned at one end in the stacking direction S of the fuel cell stack A penetrate the plates in the stacking direction S from the outside of the fuel cell stack A. Are provided with a plurality of flow paths (not shown). In these flow passages, a supply path for supplying fuel gas to the stacked body 11, a discharge path for discharging fuel gas from the stacked body 11, a supply path for supplying oxidant gas to the stacked body 11, and an oxidant gas for the stacked body 11 A discharge path for discharging the cooling water, a supply path for supplying cooling water to the stacked body 11, and a discharge path for discharging cooling water from the stacked body 11.

  Each single fuel cell has an anode electrode and a cathode electrode (not shown), and the anode electrode is electrically connected to the cathode electrode of the fuel cell unit cell adjacent to one side, and the cathode electrode is adjacent to the other side. It is electrically connected to the anode electrode of the single fuel cell. The anode electrode at one end of the laminate 11 is electrically connected to one terminal plate 12, and the cathode electrode at the other end is electrically connected to the other terminal plate 12. The electric power generated in the single fuel cell is taken out of the fuel cell stack A through a plurality of wires extending from the terminal plate 12 to the outside of the fuel cell stack A. The electric power extracted from the fuel cell stack A is supplied to, for example, an electric motor for driving a vehicle or a capacitor. The end plate 14 and the case 2 are grounded. Note that illustration of these electrical configurations is omitted.

  FIG. 4 is a schematic cross-sectional view showing the configuration of the ventilation unit. When the hydrogen gas leaks from the fuel cell main body 1 inside the case 2 while preventing the water from entering the inside from the outside of the case 2, the ventilating unit 4 stays inside the case 2. The flow path for diffusing outside the case 2 is formed. The ventilation part 4 is formed in the upper side wall 22a1, and has a through hole 40 that communicates the inside and the outside of the case 2, a cylindrical wall part 41 that is erected substantially vertically from the periphery of the through hole 40 to the outside, A plurality of ventilation holes 44 formed so as to penetrate the wall 41, a gas permeable membrane 43 disposed so as to cover the plurality of ventilation holes 44, and a lid attached to the top end 41 p of the cylindrical wall 41 Part 42. The lid portion 42 includes a cylindrical outer peripheral portion 42 a that extends around the plurality of ventilation holes 44. That is, the outer peripheral portion 42a extends from the top end 41p of the cylindrical wall portion 41 to a region around the cylindrical wall portion 41, and the height position of the bottom end 42ap of the outer peripheral portion 42a is the height position of the top end 41p of the cylindrical wall portion. Lower than. However, the bottom end 42ap is separated from the upper side wall 22a1. The outer peripheral portion 42a is separated from the cylindrical wall portion 41. The cylindrical wall portion 41 and the lid portion 42 are formed of the same material as the case 2, that is, a metal such as stainless steel or aluminum. The gas permeable film 43 is formed of a material that allows gas such as hydrogen gas or air to pass therethrough but does not pass water, and for example, Poreflon (registered trademark) manufactured by Sumitomo Electric Industries, Ltd. can be used.

  In the embodiment of FIG. 4, a cylindrical tubular wall portion 41 is erected along the peripheral edge of the circular through hole 40. A plurality of circular ventilation holes 44 are formed at approximately equal intervals along the cylindrical wall portion 41. In addition, an annular gas permeable membrane 43 is disposed outside the cylindrical wall of the cylindrical wall portion 41, whereby the plurality of ventilation holes 44 are covered with the annular membrane. In still another embodiment (not shown), the shape of the through hole 40 is another shape capable of burring, for example, an ellipse or a polygon. In still another embodiment (not shown), the shape of the plurality of ventilation holes 44 is an ellipse, a polygon, or a star. In still another embodiment (not shown), the gas permeable membrane 43 is formed for each ventilation hole 44.

  When the hydrogen gas leaks from the fuel cell main body 1 to the inside of the case 2, as shown in FIG. 5, the hydrogen gas mainly diffuses upward through the case 2 while flowing through the gap G, and passes through the through hole 40 to the ventilation unit 4. Enter. In the ventilation unit 4, the hydrogen gas passes through the ventilation hole 44 and diffuses to the outside of the case 2 through the gas permeable membrane 43 disposed outside the ventilation hole 44. Thereby, hydrogen gas does not stay inside the case 2, and the hydrogen gas concentration inside the case 2 is kept at a low concentration. Thus, since the ventilation part 4 is arrange | positioned in the upper side wall 22a1 of the case 2 where light hydrogen gas tends to gather, hydrogen gas can be efficiently and reliably exhausted outside the case 2 through the ventilation part 4.

  In the embodiment shown in FIG. 4, the outer peripheral portion 42 a of the lid portion 42 is formed so as to cover the gas permeable film 43. Therefore, as shown in FIG. 6, even when the fuel cell stack A mounted on the vehicle is exposed to the high-pressure jet Q by the high-pressure car wash of the vehicle, the outer peripheral portion 42a blocks the high-pressure jet Q and allows gas permeation. The membrane 43 is protected. Accordingly, it is possible to prevent water from adhering to the gas permeable film 43 or from entering the inside of the case 2 due to damage to the gas permeable film 43. Further, even if water 52 or dust 51 from the surroundings is directed toward the gas permeable film 43, the outer peripheral portion 42 a blocks the water 52 or dust 51 and makes it difficult for the water 52 or dust 51 to reach the gas permeable film 43. . As a result, water 52 and dust 51 are less likely to adhere to the gas permeable membrane 43, and hydrogen gas can be exhausted satisfactorily.

  In the embodiment shown in FIG. 4, the gas permeable film 43 is disposed so as to stand substantially perpendicular to the upper side wall 22a1. Therefore, as shown in FIG. 7, the water 52 and the dust 51 are not easily attached, and even if they are attached, they are not easily dropped and collected. As a result, the water 52 and the dust 51 are prevented from adhering or accumulating on the gas permeable film 43, and the hydrogen gas is exhausted satisfactorily. Even if dust adheres to the film surface, it can be easily washed away with water.

  Next, a method for manufacturing the fuel cell stack A according to the embodiment will be described. 8 to 16 are schematic cross-sectional views showing each manufacturing process of the fuel cell stack A.

  First, as shown in FIG. 8, press processing is performed on the plate material 22 s before the case body 22 is formed, and a first hole 40 a that becomes the through hole 40 and a plurality of second holes 44 a that become the plurality of ventilation holes 44. And form. The first hole 40a is formed in the portion that becomes the upper side wall of the plate member 22s, and the plurality of second holes 44a are formed in the peripheral region 40as of the first hole 40a. In the embodiment shown in FIG. 8, two circular first holes 40a are formed, and twelve circular second holes 44a are formed.

  Next, as shown in FIG. 9, burring is performed on the plate material 22s in which the first hole 40a and the plurality of second holes 44a are formed, and the peripheral region 40as of the first hole 40a is substantially omitted from the plate material 22s. A cylindrical wall portion 41 is formed by vertically rising in a cylindrical shape. The diameter of the first hole 40 a is widened to become the through hole 40, and the plurality of second holes 44 a become the plurality of ventilation holes 44 of the cylindrical wall portion 41. By using burring, the cylindrical wall portion 41 can be formed at low cost. In another embodiment (not shown), the cylindrical wall 41 is separately formed and joined to the plate by welding.

  Next, as shown in FIG. 10, a plate material 22s is formed and processed into a case shape having four side walls 22a and a bottom wall 22b, and having an opening 22c facing the bottom wall 22b. Thereby, the case main body 22 is formed. A cylindrical wall portion 41 is formed on the upper side wall 22a1 of the side wall 22a.

  Next, as shown in FIG. 11, the gas permeable membrane 43 is disposed on the outer surface of the cylindrical wall portion 41 so as to block the plurality of ventilation holes 44 of the cylindrical wall portion 41. At this time, in the embodiment of FIG. 11, an adhesive is applied to at least one of the surface on the gas permeable membrane 43 side and the surface on the cylindrical wall portion 41 side where the gas permeable membrane 43 and the cylindrical wall portion 41 are in contact. Is done. Therefore, the gas permeable membrane 43 and the cylindrical wall portion 41 are bound by the adhesive.

  Next, as shown in FIG. 12, the lid portion 42 is attached to the top end 41 p of the cylindrical wall portion 41. At this time, in the embodiment shown in FIG. 12, the lid portion 42 is attached to the top end 41p of the cylindrical wall portion 41 by friction welding. In friction welding, the back surface 42r of the lid portion 42 is rubbed against the top end 41p of the cylindrical wall portion 41 while rotating the lid portion 42 at a high speed, and at least one member is softened by the frictional heat generated at that time. To join both members. By using the friction welding, the lid portion 42 can be attached to the cylindrical wall portion 41 at a lower cost than in the case of using normal TIG welding. In another embodiment (not shown), the lid portion 42 is attached to the top end 41p of the cylindrical wall portion 41 with an adhesive.

  Next, the lid plate 21 of the case 2 is held by a fixing jig (not shown). Then, as shown in FIG. 13, the fuel cell main body 1 is pressed against the held lid plate 21 with a load P. Thereby, the fuel cell body 1 is compressed with the load P from the side in contact with the lid plate 21, that is, from the side opposite to the lid plate 21 side. Thereafter, the fuel cell body 1 continues to be compressed with the load P until the lid plate 21 and the case body 22 are fastened.

  Next, the buffer layer 3 is prepared. The buffer layer 3 has a thickness d1 larger than the distance D between the outer peripheral surface 1a of the fuel cell main body 1 and the inner peripheral surface 2a of the case 2 when the fuel cell main body 1 is accommodated in the case 2. The thickness d1 is a thickness when the load in the thickness direction applied to the buffer layer 3 is zero. Then, as shown in FIG. 14, two buffer layers 3 are arranged on each of the four outer peripheral surfaces 1 a of the fuel cell main body 1.

  Subsequently, as shown in FIG. 15, the buffer layer 3 is crushed to a thickness d2 smaller than the distance D. Since the buffer layer 3 slowly returns to its original shape, the fuel cell body 1 is accommodated in the case body 22 before the thickness of the buffer layer 3 expands to the distance D. Thereafter, the case main body 22 is fastened to the lid plate 21 with a fastening member (not shown) such as a bolt. The load P can be applied through an opening (for wiring and piping) provided in the bottom wall 22b of the case 2.

  Thereafter, as shown in FIG. 16, the buffer layer 3 returns to the original shape, that is, the thickness d <b> 1 by the restoring force. However, since the gap between the outer peripheral surface 1a and the inner peripheral surface 2a is only the distance D, the buffer layer 3 is held between the outer peripheral surface 1a and the inner peripheral surface 2a in a compressed state after returning to the thickness D. The

  Thus, the fuel cell stack A is completed. At this time, the buffer layer 3 swells and recovers its thickness while filling the gap with the case 2 according to the unevenness of each plate of the fuel cell main body 1 and each fuel cell single cell, and the outer peripheral surface 1a of the fuel cell main body 1 It arrange | positions in the compression state between the internal peripheral surfaces 2a of case 2. As shown in FIG.

  In the manufacturing method of the fuel cell stack A, the cylindrical wall portion 41 having a plurality of ventilation holes 44 is formed by burring, and the lid portion 42 is attached to the cylindrical wall portion 41 by friction welding, thereby reducing the manufacturing cost. can do.

  Next, another embodiment will be described with reference to FIG.

  FIG. 17 is a cross-sectional view illustrating a configuration example of the ventilation unit 4 according to another embodiment. In the ventilation part 4, the height position of the bottom end 42 ap of the outer peripheral part 42 a of the lid part 42 is lower than the height position of the bottom ends 44 p of the plurality of ventilation holes 44 by Dx. That is, the whole ventilation hole 44 is covered with the outer peripheral part 42a. In this case, the same effect as in the case of FIG. 4 can be obtained. In addition, the gas permeable membrane 43 can be more reliably covered with the outer peripheral portion 42a, and the gas permeable membrane 43 can be more reliably protected from water, dust, and high-pressure jet.

  Next, another embodiment will be described with reference to FIG.

  FIG. 18 is a cross-sectional view illustrating a configuration example of the ventilation unit 4 according to another embodiment. In this ventilation part 4, the cover part 42 is not provided with the outer peripheral part 42a. In this case, although the high-pressure jet and water and dust cannot be blocked, the gas permeable membrane 43 is disposed so as to stand substantially perpendicular to the upper side wall 22a1, and therefore the water 52 and dust 51 are difficult to adhere and are attached. Will soon fall off and will not collect easily (Figure 7). As a result, the water 52 and the dust 51 are prevented from adhering or accumulating on the gas permeable film 43, and the hydrogen gas is exhausted satisfactorily. Even if dust adheres to the film surface, it can be easily washed away with water. In addition, since the structure is simple, the manufacturing cost can be reduced.

  Next, another embodiment will be described with reference to FIG.

  FIG. 19 is a cross-sectional view illustrating a configuration example of the ventilation unit 4 according to another embodiment. In the ventilation part 4, the gas permeable membrane 43 is arranged inside the cylindrical wall part 41. In this case, there is a possibility that some water or dust may accumulate in the ventilation hole 44, but since the amount thereof is very small, the same effect as in the case of FIG. 4 can be obtained. Further, if the ventilation hole 44 is tapered so that the hole diameter increases toward the outside, it is possible to suppress accumulation of water and dust.

DESCRIPTION OF SYMBOLS 1 Fuel cell main body 2 Case 4 Ventilation part 11 Laminated body 22a Side wall 22a1 Upper side wall 22c Opening 40 Through-hole 41 Cylindrical wall part 44 Ventilation hole 43 Gas permeable membrane 42 Lid part A Fuel cell stack S Stacking direction

Claims (8)

A fuel cell main body including a laminate formed by laminating a plurality of fuel cell single cells along the lamination direction;
A case having four side walls and at least one opening surrounding the fuel cell main body along the stacking direction;
A fuel cell stack comprising:
The four side walls include an upper side wall disposed on the upper side when the fuel cell stack is mounted on a moving body,
The case includes a ventilation part formed on the upper side wall,
The ventilation section is
A through hole formed in the upper side wall and communicating between the inside and the outside of the case;
A cylindrical wall portion erected from the periphery of the through hole to the outside of the case;
A plurality of ventilation holes formed in the tubular wall;
A gas permeable membrane disposed so as to cover the plurality of ventilation holes;
A lid attached to the outer end of the cylindrical wall,
Comprising
Fuel cell stack. The lid portion includes a cylindrical outer peripheral portion extending around the plurality of ventilation holes.
The fuel cell stack according to claim 1. The height position of the bottom end of the outer peripheral portion of the lid portion is lower than the height position of the bottom ends of the plurality of ventilation holes,
The fuel cell stack according to claim 2. The gas permeable membrane is disposed outside the cylindrical wall portion,
The fuel cell stack according to any one of claims 1 to 3. A fuel cell main body including a stack formed by stacking a plurality of fuel cell single cells along the stacking direction; four side walls surrounding the fuel cell main body along the stacking direction; and at least one opening. A fuel cell stack including a case in which the fuel cell main body is housed, wherein the four side walls include an upper side wall disposed on the upper side when the fuel cell stack is mounted on a moving body. The case includes a ventilation part formed on the upper side wall, and the ventilation part is formed on the upper side wall and communicates with an inner side and an outer side of the case from the periphery of the through hole. A cylindrical wall portion erected to the outside of the case, a plurality of ventilation holes formed in the cylindrical wall portion, a gas permeable membrane disposed so as to cover the plurality of ventilation holes, and the cylindrical wall A lid part attached to the outer end of the part; A method of manufacturing a fuel cell stack comprising,
Preparing a plate having a first hole to be the through hole and a plurality of second holes to be formed in a peripheral region of the first hole and to be the plurality of ventilation holes;
A step of raising a peripheral region of the first hole from the plate material by burring to form the cylindrical wall portion having the plurality of ventilation holes;
Processing the plate material into a case having the four side walls and the at least one opening;
Arranging the gas permeable membrane so as to cover the plurality of ventilation holes of the cylindrical wall portion;
Attaching the lid to the outer end of the cylindrical wall;
Comprising
Manufacturing method of fuel cell stack. The lid portion includes a cylindrical outer peripheral portion extending around the plurality of ventilation holes.
The method for producing a fuel cell stack according to claim 5. The height position of the bottom end of the outer peripheral portion of the lid portion is lower than the height position of the bottom ends of the plurality of ventilation holes,
The manufacturing method of the fuel cell stack according to claim 6. The gas permeable membrane is disposed outside the cylindrical wall portion.
The method for manufacturing a fuel cell stack according to any one of claims 5 to 7.

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