Fuel cell stack

Abstract

To favorably ventilate the inside of a housing of a fuel cell stack.SOLUTION: A fuel cell stack comprises: a cell laminate; a housing that surrounds the cell laminate; a closing part that is arranged in close contact with end faces of the cell laminate; and a plurality of partitioning member that extend to divide a space between an inside surface of the housing and an outside surface of the cell laminate into a plurality of spaces. The closing part is provided with an air inlet port, and the housing is provided with an air exhaust port. The closing part has a passage forming part that forms a communication channel for communicating the air inlet port, the plurality of spaces, and the air exhaust port, with each other.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a fuel cell stack with a ventilation function. [Background technology]

[0002] In recent years, technological development has been conducted on fuel cells that contribute to energy efficiency in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy. As a technology related to fuel cell stacks used in this type of fuel cell, a technology that ventilates the inside of a case that houses the fuel cell has been known (see, for example, Patent Document 1). The case described in Patent Document 1 is provided with an air intake and an air exhaust, and the case is configured so that air taken in from the outside through the air intake passes through the case and is exhausted from the air exhaust. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-302606 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of fuel cell stack, the case may be divided into multiple spaces, making it difficult to ventilate the entire case using the flow of air taken into the case through the air intake. [Means for solving the problem]

[0005] A fuel cell stack according to one aspect of the present invention includes a cell stack formed by stacking a plurality of power-generating cells in a predetermined direction, a housing surrounding the cell stack, a closing section disposed adjacent to an end face of the cell stack in the predetermined direction and attached to the end of the housing in the predetermined direction so as to close an opening in the end face of the housing, and a plurality of partition members extending in the predetermined direction so as to divide the space between the inner surface of the housing and the outer surface of the cell stack into a plurality of spaces, including a first space and a second space. The closing section is provided with a first air port, which is either an air inlet for taking in air from the outside or an air outlet for discharging air to the outside, and the housing is provided with a second air port, which is the other of the air inlet and the air outlet and communicates with either the first space or the second space. The closing section has a passage forming section that forms a communication flow path connecting the first air port with the first space and the second space. [Effects of the Invention]

[0006] According to the present invention, the entire interior of the fuel cell stack housing can be well ventilated. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view schematically showing the overall configuration of a fuel cell stack according to an embodiment of the present invention; [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3 . [Figure 5] 5 is a cross-sectional view taken along line VV in FIG. 4. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 4. [Figure 7] Enlarged view of part VII in Figure 4. [Figure 8] FIG. 3 is a diagram schematically illustrating the flow of cooling air through a fuel cell stack according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to Figs. 1 to 8. A fuel cell stack according to an embodiment of the present invention is a main component of a fuel cell. The fuel cell is mounted, for example, in a vehicle and can generate electric power for driving the vehicle. The fuel cell can also be mounted in moving bodies other than vehicles, such as aircraft and ships, robots, and various industrial machines.

[0009] FIG. 1 is a perspective view showing a schematic view of the overall configuration of a fuel cell stack 100 according to an embodiment of the present invention. For convenience, three mutually orthogonal axial directions as shown in the figure are defined as the front-rear direction, the left-right direction, and the up-down direction, and the configuration of each part will be described in accordance with these definitions. The downward direction in the up-down direction in FIG. 1 corresponds to the direction of gravity. The front-rear direction in FIG. 1 corresponds to the stacking direction of the fuel cell stack 100. Note that the front-rear direction and the left-right direction in FIG. 1 are not necessarily the same as the front-rear direction and the left-right direction of a vehicle.

[0010] 1, the fuel cell stack 100 has a cell stack 10, end units 40 arranged at both front-rear end portions of the cell stack 10, and a case 30 arranged around the cell stack 10, and has a generally rectangular parallelepiped shape as a whole. The length of the fuel cell stack 100 in the left-right direction is longer than the length in the up-down direction.

[0011] Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1, and Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1. As shown in Figs. 1 to 3, the case 30 has a lower case 31 that defines a substantially rectangular parallelepiped lower space SP1, and an upper case 32 that defines a substantially rectangular parallelepiped upper space SP2. The upper case 32 is provided above the lower case 31 via a partition wall 33. The case 30 is formed by a plurality of side walls 300 that extend vertically or horizontally. The side walls 300 are made of a metal such as aluminum or iron.

[0012] The cell stack 10 is housed in the lower space SP1. When the cell stack 10 is housed therein, a substantially frame-shaped surplus space SP10 is formed between the inner wall surface 301 of the side wall 300 and the outer surface 110 of the cell stack 10. Although not shown, the upper space SP2 houses a control unit (e.g., a voltage control unit) that controls the fuel cell. A through-hole 33a that penetrates the partition wall 33 in the vertical direction is opened, and the lower space SP1 (strictly speaking, a part of the lower space SP1, as will be described later) and the upper space SP2 communicate with each other via the through-hole 33a.

[0013] The case 30 is formed by a plurality of side walls 300 extending horizontally (front-rear and left-right) or up-down. As shown in Fig. 3, the front and rear surfaces of the lower case 31 are open. Therefore, openings 311, 312 are provided in the front and rear surfaces of the lower case 31, and the openings 311, 312 are closed by a pair of front and rear end units 40.

[0014] The pair of end units 40, 40 have a pair of terminal plates 41, 41 arranged adjacent to the front end surface and rear end surface of the cell stack 10, a pair of insulating plates 42, 42 arranged adjacent to the pair of terminal plates 41, 41 and on the front-to-back outside of the pair of terminal plates 41, 41, and a pair of end plates 43, 43 arranged adjacent to the pair of insulating plates 42, 42 and on the front-to-back outside of the pair of insulating plates 42, 42.

[0015] The terminal plate 41 is a generally rectangular metal plate-like member and has a terminal portion for extracting the electric power generated by the electrochemical reaction in the cell stack 10. The insulating plate 42 is a generally rectangular non-conductive resin or rubber plate-like member that electrically insulates the terminal plate 41 from the end plate 43. The end plate 43 is a generally rectangular metal or high-strength resin plate-like member. The terminal plate 41 and the insulating plate 42 are disposed inside the lower case 31. The pair of end plates 43 are fastened to the front and rear end faces of the lower case 31 by bolts (not shown).

[0016] The cell stack 10 has a plurality of power-generating cells 1 (for convenience, only a single power-generating cell 1 is shown in FIG. 3) arranged in the lower space SP1. The power-generating cell 1 has an integrated electrode assembly (UEA) 2 having a membrane electrode assembly including an electrolyte membrane and electrodes, and separators 3 arranged on both sides of the integrated electrode assembly 2 in the front-to-rear direction and sandwiching the integrated electrode assembly 2. The integrated electrode assemblies 2 and the separators 3 are arranged alternately in the front-to-rear direction. The integrated electrode assembly 2 can also be called a membrane electrode structure.

[0017] The separator 3 is formed by joining together a pair of corrugated front and rear plates (front plate and rear plate) made of stainless steel, titanium, titanium alloy, etc. An anode flow path through which a fuel gas containing hydrogen flows is formed between the rear plate and the integrated electrode assembly 2. A cathode flow path through which an oxidant gas containing oxygen (e.g., air) flows is formed between the front plate and the integrated electrode assembly 2. A cooling flow path through which a coolant flows is formed between the pair of plates.

[0018] The electrolyte membrane of the integrated electrode assembly 2 is, for example, a solid polymer electrolyte membrane. The anode electrode is formed on the front surface of the electrolyte membrane and has an electrode catalyst layer that serves as a reaction field for electrode reactions, and a gas diffusion layer that is provided on the front surface of the electrode catalyst layer and diffuses and supplies fuel gas. The cathode electrode is formed on the rear surface of the electrolyte membrane and has an electrode catalyst layer that serves as a reaction field for electrode reactions, and a gas diffusion layer that is provided on the rear surface of the electrode catalyst layer and diffuses and supplies oxidant gas.

[0019] At the anode electrode, fuel gas supplied via the anode flow channel and gas diffusion layer is ionized by the action of a catalyst and moves through the electrolyte membrane to the cathode electrode. The electrons generated at this time pass through an external circuit and are extracted as electrical energy. At the cathode electrode, oxidant gas supplied via the cathode flow channel and gas diffusion layer reacts with hydrogen ions introduced from the anode electrode and electrons transferred from the anode electrode to produce water. The produced water provides an appropriate humidity to the electrolyte membrane, and excess water is discharged outside the integrated electrode assembly 2.

[0020] As shown in Fig. 1, a plurality of through holes 401 to 406 are opened through the rear end unit 40 in the front-rear direction. The through holes 401 to 406 are not opened in the front end unit 40. As shown in Fig. 2, a plurality of through holes 101 to 106 are opened in the cell stack 10 at positions corresponding to the through holes 401 to 406. The through holes 101 to 106 include through holes provided in the integrated electrode assembly 2 and through holes provided in the separator 3.

[0021] As shown by the solid arrow in Fig. 1, fuel gas is supplied to the fuel cell stack 100 via the through-holes 401. This fuel gas is guided to the anode flow path of each power-generating cell 1 via the through-holes 101 in the cell stack 10. After passing through the anode flow path, the fuel gas passes through the through-holes 106 and is then discharged from the through-holes 406 as shown by the solid arrow in Fig. 1.

[0022] As shown by the dotted arrow in Fig. 1, an oxidant gas is supplied to the fuel cell stack 100 via the through-holes 404. This oxidant gas is guided to the cathode flow path of each power-generating cell 1 via the through-holes 104 of the cell stack 10. After passing through the cathode flow path, the oxidant gas passes through the through-holes 103 and is discharged from the through-holes 403 as shown by the dotted arrow in Fig. 1.

[0023] A cooling medium is supplied to the fuel cell stack 100 via the through holes 405, as shown by the dashed-dotted arrows in Fig. 1. This cooling medium is guided to the cooling flow paths of each power-generating cell 1 via the through holes 105 in the cell stack 10. After passing through the cooling flow paths, the cooling medium passes through the through holes 102 and is discharged from the through holes 402, as shown by the dashed-dotted arrows in Fig. 1.

[0024] 1 and 2, substantially rod-shaped or plate-shaped guide members 50 extending in the front-rear direction are interposed between the outer surface 110 of the cell stack 10 and the inner wall surfaces 301 of the side walls 300 of the lower case 31. Specifically, as shown in Fig. 2, an upper guide member 51, a left guide member 52, a lower guide member 53, and a right guide member 54 are interposed on the inner wall surfaces 301 of the upper, left, lower, and right side walls 300 of the lower case 31, respectively. The multiple guide members 50 (51 to 54) have the same configuration.

[0025] The guide member 50 is fitted into a recess 315 provided in the inner wall surface 301 of the side wall 300. As shown in FIG. 3, the guide member 50 extends in the front-to-rear direction beyond the openings 311, 312 of the lower case 31. The front and rear ends of the guide member 50 are fitted into fitting portions 431 (recesses or through holes) provided in the end plate 43. This fixes the guide member 50 to the case 30.

[0026] 2, the guide member 50 protrudes toward the outer surface 110 of the cell stack 10, and a concave engaging recess 55 is provided at the tip of the guide member 50. A convex engaging protrusion 115 is provided on the outer surface 110 of the cell stack 10, corresponding to the engaging recess 55. The engaging protrusion 115 engages with the engaging recess 55, thereby positioning the cell stack 10 in the case 30 via the guide member 50.

[0027] When such a guide member 50 is provided, the approximately frame-shaped excess space SP10 between the inner wall surface 301 of the side wall 300 and the outer surface 110 of the cell stack 10 is divided into multiple spaces via the guide member 50. That is, it is divided into an upper left space (upper left space SP11), a lower left space (lower left space SP12), an upper right space (upper right space SP14), and a lower right space (lower right space SP143). The upper left space SP11 and the upper right space SP14 communicate with the upper space SP2 via the through-hole 33a.

[0028] The upper-left space SP11 and the upper-right space SP14 communicate with each other via the upper space SP2. Meanwhile, communication between the upper-left space SP11, the lower-left space SP12, and the lower-right space SP13, and communication between the upper-right space SP14, the lower-right space SP13, and the lower-left space SP12 are blocked by the guide member 50. For this reason, there is no gas flow between these spaces, or there is only a slight gas flow via gaps between the guide member 50 and the side wall 300 and between the cell stack 10 and the side wall 300.

[0029] The gas flow paths (anode flow path, cathode flow path) of the cell stack 10 are sealed by a sealing member provided between the integrated electrode assembly 2 and the separator 3 so as to surround the gas flow paths. The sealing member is made of flexible rubber, resin, or the like, and ensures airtightness by adhering closely to the surfaces of the integrated electrode assembly 2 and the separator 3. A certain amount of gas leaks from the inside of the cell stack 10 through this sealing member. The leaked gas accumulates in the surplus space SP10. This may increase the concentration of hydrogen gas contained in the fuel gas in the surplus space SP10.

[0030] To prevent this increase in hydrogen gas concentration, specifically to keep the hydrogen gas concentration below a predetermined value, the fuel cell stack 100 of this embodiment is provided with a ventilation device. The predetermined value is, for example, the flammability limit of hydrogen gas (the lower limit concentration of the fuel range) or a value lower than the flammability limit. The configuration of the ventilation device will be described below.

[0031] As shown in FIG. 2, the case 30 is provided with a plurality of ventilation openings 61-64 penetrating the side wall 300. The ventilation opening 61 is provided in the right side wall 300 of the upper case 32, and connects an upper space SP2 inside the case to the space outside the fuel cell stack 100 via the ventilation opening 61. The ventilation opening 62 is provided in the right side wall 300 of the lower case 31, and connects a lower-right space SP13 to the space outside via the ventilation opening 62. The ventilation opening 63 is provided in the lower side wall 300 of the lower case 31, and connects a lower-left space SP12 to the space outside via the ventilation opening 63. The ventilation opening 64 is provided in the left side wall 300 of the lower case 31, and connects an upper-left space SP11 to the space outside via the ventilation opening 64. The ventilation openings 61-64 are provided, for example, in the center of the case 30 in the front-rear direction.

[0032] A filter unit 65 is provided in each of the ventilation openings 61 to 64. The filter unit 65 has a cover 66 attached to the side wall 300 from the outside so as to cover the ventilation openings 61 to 64 with bolts or the like, and a filter 67 fixed to the cover 66 so as to shield the ventilation openings 61 to 64. The cover 66 has a mesh portion or louver portion that covers the ventilation openings 61 to 64, prevents relatively large foreign objects from entering the case 30, and protects the filter 67. The filter 67 is an air filter that removes dust and other particles from passing gas, particularly from air flowing into the case 30 from the outside, thereby preventing the dust and other particles from entering the case 30 and protecting the cell stack 10.

[0033] Because hydrogen gas has a smaller specific gravity than air, hydrogen gas leaking from the cell stack 10 rises within the excess space SP10. This flow of hydrogen gas allows the hydrogen gas to be discharged to the outside space through a ventilation opening (for example, ventilation opening 61) by natural ventilation. This allows the inside of the case 30 to be ventilated.

[0034] However, natural ventilation does not occur throughout the entire surplus space SP10. For example, natural ventilation is difficult to achieve in areas AR1, AR2, and AR3 in Figure 2, and hydrogen gas tends to accumulate in these areas AR1, AR2, and AR3. Therefore, in this embodiment, the ventilation device is further configured as follows to ensure that hydrogen gas can be efficiently discharged throughout the entire surplus space SP10.

[0035] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. 4 includes a rear view of the rear insulating plate 42. FIG. 5 is a cross-sectional view taken along line VV in FIG. 4 (a cross-sectional view taken along reference line L3 in FIG. 7), and FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 4. FIGS. 5 and 6 also show a rear end plate 43. As shown in FIG. 4, an engaging protrusion 421 similar to that of the cell stack 10 is provided on the outer surface of the insulating plate 42, and the engaging protrusion 421 engages with the engaging recess 55 of the guide member 50. Between the inner wall surface 301 of the side wall 300 of the lower case 31 and the outer surface of the insulating plate 42, spaces SP11 to SP14 (FIG. 2) between the lower case 31 and the cell stack 10 exist beyond the cell stack 10 in the front-to-rear direction.

[0036] As shown in FIG. 6, the insulating plate 42 has a front surface 42f that contacts the terminal plate 41 and a rear surface 42r that contacts the end plate 43. As shown in FIG. 4, the insulating plate 42 has through holes 401-406 (FIG. 1) that communicate with the insulating plate 42 in the front-to-rear direction. Sealing members 422 such as O-rings are attached to the rear surface 42r of the insulating plate 42 around the through holes 401-403 and around the through holes 404-406 so as to surround the through holes 401-403 and 404-406, respectively. The insulating plate 42 and the end plate 43 are pressed against each other via the sealing members 422, thereby sealing the periphery of the through holes 401-406 from the excess space SP10 (spaces SP11-SP14) between the case 30 and the cell stack 10.

[0037] A plurality of ribs 423 are provided on the rear surface 42r of the insulating plate 42, between the pair of left and right seal members 422, 422. As shown in Figures 5 and 6, the ribs 423 protrude rearward from the rear surface of a babe portion 424 having a predetermined thickness in the front-rear direction. The tip surfaces, i.e., top surfaces (rear end surfaces), of the ribs 423 form the rear surface (rear end surface) 42r of the insulating plate 42 and abut against the end plate 43.

[0038] Fig. 7 is an enlarged view of part VII in Fig. 4. As shown in Fig. 7, the rib 423 has a plurality of vertical ribs 423a arranged at equal intervals in the left-right direction along a plurality of reference lines L1 extending generally parallel to one another in the up-down direction, and a plurality of horizontal ribs 423b arranged at equal intervals in the up-down direction along a plurality of reference lines L2 extending generally parallel to one another in the left-right direction. The left-right widths of the vertical ribs 423a and the vertical widths of the horizontal ribs 423b are the same.

[0039] As a result, the ribs 423 are formed in a lattice pattern as a whole, as shown in Fig. 4. Providing the lattice-shaped ribs 423 can increase the rigidity of the insulating plate 42 made of a resin material or the like. As shown in Fig. 7, a plurality of rib recesses 420, each of which is substantially rectangular in plan view and surrounded by the ribs 423, are provided inside the lattice-shaped ribs 423.

[0040] As shown in Fig. 4, a plurality of notches 425, 426 are provided at both left and right ends of the plurality of horizontal ribs 423b, and extend across the plurality of horizontal ribs 423b in the up-down direction. Furthermore, a plurality of notches 427 are provided at the lower ends of the plurality of vertical ribs 423a, and extend across the plurality of vertical ribs 423a in the left-right direction. Fig. 5 shows the configuration of notch 425. The configurations (width and depth) of the plurality of notches 425 to 427 are identical to one another.

[0041] 5, bottom surface 425a of notch 425 extends substantially parallel to rear surface 42r of insulating plate 42. Notch 425 is set to a predetermined depth, as indicated by the arrow, to allow smooth flow of hydrogen gas through notch 425, and is also set to a predetermined width, as shown in FIG.

[0042] 4 and 7, the plurality of cutouts 425 are provided along a reference line L3 extending in the vertical direction from the upper end surface 42u to the lower end surface 42d of the insulating plate 42. The upper-right space SP14 and the lower-right space SP13 communicate with each other through the plurality of cutouts 425. Therefore, the plurality of cutouts 425 form a communication flow path PA1 that communicates between the spaces SP13 and SP14.

[0043] 4, the plurality of cutouts 426 are similarly provided along a reference line extending in the vertical direction from the upper end surface 42u to the lower end surface 42d of the insulating plate 42. The upper-left space SP11 and the lower-left space SP12 communicate with each other via the plurality of cutouts 426. Therefore, the plurality of cutouts 426 form a communication flow path PA2 that communicates between the spaces SP11 and SP12.

[0044] 4 and 7, the multiple cutouts 427 are provided along a reference line L4 extending in the left-right direction, from the right-end rib recess 420 to the left-end rib recess 420. The right-side communication flow path PA1 communicates with the left-side communication flow path PA2 via the multiple cutouts 427. Therefore, the multiple cutouts 427 form a communication flow path PA3 that communicates the communication flow paths PA1 and PA2. The rib recess 420 at the position where the communication flow paths PA1 and PA3 intersect may be referred to as a communication rib recess 420a (FIG. 7) to distinguish it from the other rib recesses 420.

[0045] As shown in Fig. 5, end plate 43 has air intake port 430 that penetrates end plate 43 in the front-rear direction. Air intake port 430 is provided at a position (dotted line in Fig. 7) facing communicating rib recess 420a. Fan 200 is connected to air intake port 430 via, for example, a tube or piping, and cooling air is blown from fan 200 to air intake port 430. Note that cooling air may also be blown from fan 200 to air intake port 430 without using a tube or piping.

[0046] In this embodiment, the inside of the case 30 is ventilated by forced ventilation, in which cooling air is blown from the blower 200. FIG. 8 is a diagram schematically illustrating the flow of the cooling air. As shown in FIG. 8, when cooling air is blown into the fuel cell stack 100 through the air intake port 430, part of the cooling air flows upward toward the upper right space SP14 in the lower case 31 through the communication flow path PA1 formed by the cutout 425, as indicated by arrow A1. The cooling air then changes its flow direction forward, as indicated by the arrow in FIG. 5, and flows forward through the upper right space SP14. The air in the upper right space SP14 flows into the upper space SP2 in the upper case 32 through the through-hole 33a, as indicated by the arrow in FIG. 8. The air then flows out of the case 30 through the ventilation port 61, which serves as an exhaust port.

[0047] Furthermore, as indicated by arrow A2, a portion of the cooling air blown through air intake port 430 flows downward through communication flow path PA1 toward lower-right space SP13 in lower case 31. The cooling air then changes direction and flows forward through lower-right space SP13 as indicated by the arrow in Fig. 5. The air in lower-right space SP13 uses ventilation port 62 as an exhaust port and flows out of the case through ventilation port 62 as indicated by the arrow in Fig. 8.

[0048] Furthermore, as shown by arrow A3, a portion of the cooling air blown through air intake port 430 passes through communication flow path PA3 formed by notch 427 and flows into communication flow path PA2 formed by notch 426. As shown by arrow A4, a portion of the cooling air in communication flow path PA2 flows downward toward the lower-left space SP12 in lower case 31. The cooling air then changes direction forward and flows forward through lower-left space SP12. The cooling air then uses ventilation port 63 as an exhaust port and flows out of the case through ventilation port 63.

[0049] The remaining cooling air in the communication flow path PA2 flows upward toward the upper-left space SP11 in the lower case 31, as indicated by arrow A5. The cooling air then changes direction and flows forward through the upper-left space SP11. The air in the upper-left space SP11 flows into the upper space SP2 in the upper case 32 through the through-hole 33a, as indicated by the arrow. The air then flows out of the case through the ventilation opening 61, which serves as an exhaust opening.

[0050] As described above, in this embodiment, forced ventilation that sends cooling air from a single air intake port 430 causes cooling air to flow through the multiple spaces SP11-SP14 around the cell stack 10. Therefore, even when the inside of the case 30 is divided into the multiple spaces SP11-SP14 by the guide member 50, the inside of the case 30 can be sufficiently ventilated, and hydrogen gas can be efficiently discharged from the spaces SP11-SP14.

[0051] The blower 200 may be driven constantly or at a predetermined timing. For example, a sensor may be provided to detect the hydrogen concentration in the surplus space SP10, and when the hydrogen concentration detected by the sensor reaches or exceeds a predetermined value, a controller may output a control signal to the blower 200 to drive the blower 200.

[0052] According to this embodiment, the following effects can be achieved. (1) A fuel cell stack 100 includes a cell stack 10 formed by stacking a plurality of power-generating cells 1 in the front-rear direction, a case 30 surrounding the cell stack 10, an end unit 40 disposed adjacent to the front-rear end face of the cell stack 10 and attached to the front-rear end of the case 30 so as to close openings 311, 312 in the front-rear end face of the case 30, and a plurality of guide members 50 extending in the front-rear direction so as to divide a lower space SP1 between an inner wall surface (inner surface) 301 of the case 30 and an outer surface 110 of the cell stack 10 into a plurality of spaces SP11 to SP14 (FIGS. 1 to 3). The end unit 40 is provided with an air intake port 430 for taking in air from the outside (FIG. 5). The case 30 is provided with ventilation ports 61 to 64 as exhaust ports (FIG. 2). The end unit 40 has cutouts 425 to 427 that form communication flow paths PA1 to PA3 that connect the spaces SP11 to SP14 (FIG. 8).

[0053] With this configuration, when the inside of the case 30 is divided into a plurality of spaces SP11 to SP14 by the guide member 50, the cooling air blown through the air supply port 430 can be supplied to the plurality of spaces SP11 to SP14 via the communication flow paths PA1 to PA3. As a result, the entire surplus space SP10 inside the case can be efficiently ventilated, and hydrogen gas accumulated in the surplus space SP10 can be efficiently discharged to the outside.

[0054] (2) The end unit 40 has a conductive terminal plate 41 arranged adjacent to the front-rear end face of the cell stack 10, an insulating plate 42 arranged adjacent to the terminal plate 41, and an end plate 43 arranged adjacent to the insulating plate 42 (FIG. 3). An air supply port 430 is provided through the end plate 43 (FIG. 5). Notches 425-427 that form the communication flow paths PA1-PA3 are provided in the insulating plate 42 (FIG. 4). This makes it easy to form the communication flow paths PA1-PA3.

[0055] (3) The insulating plate 42 has a front surface 42f facing the terminal plate 41 and a rear surface 42r facing the end plate 43 (FIG. 5). The communication flow path PA1 extends from the upper end surface 42u of the insulating plate 42 facing the upper-right space SP14 to the lower end surface 42d of the insulating plate 42 facing the lower-right space SP13, and onto the rear surface 42r (FIGS. 4 and 5). This allows the spaces SP13 and SP14 to easily communicate with each other via the insulating plate 42, whose shape is relatively easy to change, i.e., via the notch 425 of the insulating plate 42.

[0056] (4) The insulating plate 42 has reinforcing ribs 423 provided on the rear surface 42r (FIG. 7). The communicating flow paths PA1-PA3 are formed by notches 425-427 provided at the tops of the ribs 423 (FIGS. 4 and 7). As a result, the areas of the notches 425-427 are small, making it easy to form the communicating flow paths PA1-PA3.

[0057] (5) The guide member 50 is a positioning member extending in the front-rear direction, and the cell stack 10 has an engaging protrusion 115 provided on the outer surface 110 so as to engage with the engaging recess 55 of the guide member 50 (FIG. 2). The guide member 50 extends in the front-rear direction so as to block communication between the spaces SP11 to SP14, so that the guide member 50 can be constructed firmly and the cell stack 10 can be stably positioned.

[0058] (6) Case 30 has lower case 31 that defines lower space SP1, and upper case 32 that communicates with lower space SP1 and defines upper space SP2 above lower case 31 (FIG. 3). Ventilation openings 62-64 are provided in lower case 31, and ventilation opening 61 is provided in upper case 32 (FIG. 2). This allows cooling air supplied via blower 200 to be efficiently exhausted from ventilation openings 61-64 in upper case 32 and lower case 31, respectively.

[0059] The above embodiment can be modified in various ways. Some modifications will be described below. In the above embodiment, the blower 200 blows cooling air into the case 30 to ventilate the inside of the case 30. However, the inside of the case 30 may be ventilated by drawing air into the case 30 with a fan or the like. Therefore, the end unit 40 may be provided with an exhaust port (air exhaust port) that exhausts air to the outside as the first air vent, instead of the air supply port 430 (air intake port) that takes in air from the outside. Furthermore, the case 30 may be provided with an air intake port that functions as an air supply port as the second air vent, instead of the ventilation ports 61-64 (air exhaust port) that function as an exhaust port.

[0060] In the above embodiment, the communication channels PA1 to PA3 are formed by providing notches 425 to 427 in the ribs 423 provided on the insulating plate 42, but the configuration of the channel formation portion is not limited to that described above. The communication channels may be formed on the front surface 42f (first surface) of the insulating plate 42, rather than on the rear surface 42r (second surface) of the insulating plate 42 where the ribs 423 are provided. In the above embodiment, multiple communication channels PA1 to PA3 are formed, but the number of communication channels is not limited to that described above. In the above embodiment, the communication channel PA1 extends from the upper end surface 42u (first edge) of the insulating plate 42 facing the upper-right space SP14 to the lower end surface 42d (second edge) of the insulating plate 42 facing the lower-right space SP13, but the configuration of the communication channels is not limited to that described above.

[0061] In the above embodiment, the case 30 serving as the housing is provided with multiple ventilation openings 61-64. However, a single ventilation opening may be provided. For example, only the uppermost ventilation opening 61 may be provided. In the above embodiment, the end unit 40 serving as the blocking portion is configured by the conductive terminal plate 41 (first member), the insulating plate 42 (second member), and the end plate 43 (third member). However, the configuration of the blocking portion is not limited to the above. That is, the blocking portion may have any configuration as long as it is provided with either an air intake port or an air exhaust port and has a passage forming portion that forms a communication flow path connecting the first air port (air supply port 430) and two of the multiple spaces SP11-SP14 (first space, second space). The combination of the first space and the second space may be any combination, such as spaces SP13 and SP14, spaces SP11 and SP12, spaces SP11 and SP14, or spaces SP12 and SP13.

[0062] In the above embodiment, the surplus space SP10 between the inner wall surface (inner surface) 301 of the case 30 and the outer surface 110 of the cell stack 10 is divided into a plurality of spaces SP11 to SP14 by the guide member 50 as a positioning member extending in a predetermined direction, but the partition member that divides the space SP10 is not limited to a positioning member. In the above embodiment, the space SP10 is divided into four spaces, but the space SP10 may be divided into spaces other than four as long as it is divided into a plurality of spaces including at least a first space (for example, an upper right space SP14) and a second space (for example, a lower right space SP13).

[0063] In the above embodiment, the outer surface 110 of the cell stack 10 is provided with an engaging protrusion 115 that engages with the guide member 50, but an engaging recess may be provided instead of an engaging protrusion. The guide member 50 may be fitted into the guide member 50 instead of being engaged with it. Therefore, the configuration of the positioning member is not limited to that described above, and the configuration of the positioned portion provided on the outer surface 110 of the cell stack 10 is not limited to that described above.

[0064] In the above embodiment, the case 30 (housing) is configured by the lower case 31 (first housing) that forms the lower space SP1 and the upper case 32 (second housing) that forms the upper space SP2 (another space) in the lower case 31, but the configuration of the housing is not limited to that described above. In the above embodiment, the upper case 32 and the lower case 31 are provided with the ventilation openings 61 to 64, respectively, but ventilation openings (air intake openings or air exhaust openings) may be provided only in the upper case 32 or only in the lower case 31.

[0065] The above description is merely an example, and the present invention is not limited to the above-described embodiment and modifications as long as the features of the present invention are not impaired. One or more of the above-described embodiment and modifications can be arbitrarily combined, and modifications can also be combined with each other.

[0066] 1 power generation cell, 10 cell stack, 30 case, 31 lower case, 32 upper case, 40 end unit, 41 terminal plate, 42 insulating plate, 42f front surface, 42r rear surface, 42u upper end surface, 42d lower end surface, 43 end plate, 45 guide member, 61 to 64 ventilation opening, 100 fuel cell stack, 423 rib, 423 notch, 430 air intake port, 515 engaging protrusion, SP1 lower space, SP2 upper space, SP10 excess space, SP11 to SP14 spaces, PA1 to PA3 communicating flow path

Claims

1. a cell stack formed by stacking a plurality of power generating cells in a predetermined direction; a housing that surrounds the cell stack; a closing portion disposed adjacent to an end surface of the cell stack in the predetermined direction and attached to an end portion of the housing in the predetermined direction so as to close an opening in the end surface of the housing; a plurality of partition members extending in the predetermined direction so as to divide a space between an inner surface of the housing and an outer surface of the cell stack into a plurality of spaces including a first space and a second space; The closing portion is provided with a first air vent which is either an air intake port for taking in air from the outside or an air exhaust port for exhausting air to the outside, a second air vent, which is the other of the air intake port and the air exhaust port and communicates with the first space or the second space, is provided in the housing; The blocking portion has a passage forming portion that forms a communication flow path that connects the first air port, the first space, and the second space.

2. 2. The fuel cell stack according to claim 1, the blocking portion has a first member having conductivity and arranged adjacent to the end surface of the cell stack, a second member having insulation and arranged adjacent to the first member, and a third member arranged adjacent to the second member, the first air vent is provided through the third member, The fuel cell stack is characterized in that the passage forming portion is provided in the second member.

3. 3. The fuel cell stack according to claim 2, the second member has a first surface facing the first member and a second surface facing the third member, a fuel cell stack characterized in that the communicating flow path is provided on the second surface so as to extend from a first edge portion of the second member facing the first space to a second edge portion of the second member facing the second space.

4. 4. The fuel cell stack according to claim 3, the second member has a rib provided on the second surface, The fuel cell stack according to claim 1, wherein the passage forming portion is formed by a notch provided at the top of the rib.

5. 5. The fuel cell stack according to claim 1, the partition member is a positioning member extending in the predetermined direction, The cell stack has a positioned portion provided on the outer surface thereof so as to engage or fit with the positioning member.

6. 5. The fuel cell stack according to claim 1, the housing includes a first housing that forms the space, and a second housing that communicates with the space and forms another space above the first housing; The fuel cell stack is characterized in that the second air vent is provided in at least one of the first housing and the second housing.

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