JP2013219000A - Fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell stack that prevents a power generation failure therein due to accumulated water even when a vehicle is inclined.SOLUTION: A fuel cell stack 1 is mounted in a vehicle. In the fuel cell stack 1, a pair of end plates 25a and 25b are arranged on both ends, in a lamination direction, of a laminate including a membrane electrode assembly and separators. In the lamination direction, a first gas outlet passage and a second gas outlet passage are provided for discharging reactant gas used in power generation. The end plate 25a arranged on a first side has gas manifolds 10a to 10d. The end plate 25b arranged on a second side has water storage sections 40, on the second side, that communicate with the first gas outlet passage and the second gas outlet passage.

Description

  The present invention relates to a fuel cell stack.

A solid polymer electrolyte membrane type fuel cell includes an electrolyte membrane electrode structure formed by sandwiching a solid polymer electrolyte membrane between an anode electrode and a cathode electrode, and the electrolyte membrane electrode structure is sandwiched between a pair of separators. This constitutes a unit fuel cell. The fuel cell stack is configured by laminating a plurality (tens to hundreds) of unit fuel cells.
Also, a so-called fuel cell vehicle is known which travels by mounting a fuel cell stack on a vehicle and driving an electric motor with electric energy generated from the fuel cell stack.

  For example, in Patent Document 1, a plurality of fuel cells are stacked to form a cell stack, end plates are arranged on both sides of the cell stack, and through holes and ends formed in the stacking direction of the cell stack. The through hole of the plate communicates to form a communication hole through which a fluid composed of a fuel gas, an oxidant gas, and a cooling medium flows, and the end of the resin material pipe through which the fluid flows communicates with the communication hole. A fuel cell stack fastened to a plate is described.

  In this type of fuel cell stack, as a fuel gas, for example, a gas mainly containing hydrogen (hereinafter referred to as “hydrogen-containing gas”) is supplied to the anode electrode via the first reaction gas channel. . In addition, as the oxidant gas, for example, a gas containing mainly oxygen or air (hereinafter referred to as “oxygen-containing gas”) is supplied to the cathode electrode through the second reaction gas flow path. In the fuel gas supplied to the anode electrode, hydrogen is ionized on the electrode catalyst and moves to the cathode electrode side through the electrolyte membrane. Electrons generated during that time are taken out to an external circuit and used as direct current electric energy. On the cathode electrode side, oxygen (oxygen), hydrogen ions and electrons of the oxygen-containing gas react to generate water (hereinafter referred to as “product water”).

Here, in the communication hole through which the oxygen-containing gas flows, stagnant water is generated by the generated water generated at the cathode electrode. In addition, in the communication hole through which the hydrogen-containing gas flows, stagnant water is generated due to condensation or generated water that has permeated through the electrolyte membrane electrode structure. This staying water may reduce the area of the communication hole through which each reaction gas of the oxygen-containing gas and the hydrogen-containing gas flows, or may block the communication hole. In particular, when stagnant water closes the communication hole, the reaction gas flow paths formed between the separator and the cathode electrode and between the separator and the anode electrode are also blocked to prevent the flow of each reaction gas. There is a risk of power generation failure of the fuel cell stack.
Therefore, for example, a catch tank, a drain, a water discharge valve or the like is provided in a gas manifold or the like on the opening side of the communication hole, and the accumulated water is periodically discharged from the drain or the water discharge valve.

JP 2010-55892 A

  By the way, the attitude of the fuel cell vehicle changes due to running or stopping. Therefore, when a large amount of stagnant water is temporarily generated, depending on the configuration of the fuel cell stack, the position of the fuel cell stack, the attitude of the fuel cell vehicle, etc., each reaction gas flow path is blocked by the stagnant water, There is a risk of power generation failure of the fuel cell stack.

  Specifically, in the fuel cell stack described in Patent Document 1, it is considered that one side of the communication hole is closed by an end plate in order to form a reaction gas passage. For this reason, when the fuel cell vehicle is tilted so that the end plate that closes the opening of the communication hole faces downward, the staying water moves to the end plate side by gravity, and the staying water is blocked by the end plate. . As a result, the accumulated water gathers on the end plate side, so that the level of the accumulated water in the communication hole on the end plate side rises. Therefore, the communication hole, which is the reaction gas passage, is blocked by the accumulated water, and the reaction gas cannot flow, which may cause a power generation failure of the fuel cell stack.

  Accordingly, an object of the present invention is to provide a fuel cell stack that can prevent the occurrence of power generation failure of the fuel cell stack due to stagnant water even when the vehicle is inclined.

  In order to solve the above problems, a fuel cell stack of the present invention (for example, the fuel cell stack 1 in the embodiment) is a fuel cell stack mounted on a vehicle (for example, the fuel cell automobile V in the embodiment), Provided with a laminated body (for example, laminated body 3 in the embodiment) in which an electrolyte membrane electrode structure (for example, the membrane electrode structure 7 in the embodiment) and a separator (for example, the separators 11 and 12 in the embodiment) are laminated, A pair of end plates (for example, end plates 25a and 25b in the embodiment) are disposed at both ends in the stacking direction of the stacked body, and the stacked body is used for power generation along the stacking direction. A reaction gas discharge communication hole (for example, the first gas outlet passage 32 and the second gas outlet passage 34 in the embodiment) for discharging the reaction gas is provided. Among the pair of end plates, an end plate disposed on one side in the stacking direction communicates with the reaction gas discharge communication hole and discharges the reaction gas (for example, the gas in the embodiment). Among the pair of end plates, the end plate disposed on the other side in the stacking direction has a water storage section (for example, the water storage in the embodiment) that communicates with the reaction gas discharge communication hole. Part 40) is provided.

  According to the present invention, when the vehicle is inclined to the other side in the stacking direction of the fuel cell stack, the accumulated water in the reaction gas discharge communication hole moves to the other side by gravity. Here, since the other end plate is provided with a water storage portion that communicates with the reaction gas discharge communication hole, the accumulated water that has moved to the other side is blocked in the reaction gas discharge communication hole by the end plate. Without being stopped, it moves to the water storage unit and is stored. Thereby, it is possible to suppress an increase in the water level in the reaction gas discharge communication hole due to the staying water that has moved on the other side of the reaction gas discharge communication hole. Accordingly, it is possible to prevent the reaction gas discharge communication holes from being blocked by the stagnant water in the reaction gas discharge communication holes, and thus it is possible to prevent power generation failure of the fuel cell stack. Further, as in the conventional case, the gas manifold functions as a water reservoir, and the accumulated water in the reaction gas discharge communication hole can be discharged. Therefore, even when the vehicle is tilted, it is possible to prevent power generation failure of the fuel cell stack due to the staying water.

  Further, the lowermost surface in the direction of gravity (for example, the -Z side surface 42a of the water storage member 41 in the embodiment) of the inner side surface of the water storage unit is the other side of the reaction gas discharge communication hole connected to the water storage unit. It is characterized in that it is positioned above the lowermost part in the gravitational direction (for example, the −Z side surface 34a of the second gas outlet passage 34 in the embodiment) among the ends.

  After the vehicle is inclined to the other side in the stacking direction and the accumulated water is stored in the reservoir, the accumulated water in the reservoir is returned from the reservoir to the reaction gas discharge communication hole when the vehicle returns to the horizontal level. . At this time, since the lowermost surface of the water storage portion is located above the lowermost portion of the end portion on the other side of the reaction gas discharge communication hole in the gravity direction, the accumulated water is not recirculated from the water storage portion to the reaction gas discharge communication hole. Therefore, it is possible to suppress staying in the water storage section and to quickly discharge the accumulated water. Therefore, according to this invention, in addition to the effect of Claim 1, the accumulated water in a water storage part can be discharged | emitted favorably.

  Further, the lowermost surface in the gravitational direction among the inner side surfaces of the water storage section is inclined downward in the gravitational direction from the other side toward the one side.

  According to the present invention, the lowermost surface in the gravity direction of the water storage portion is an inclined surface that is inclined downward in the gravity direction from the other side toward the one side, so that when the vehicle returns to the horizontal, The accumulated water can be discharged along the inclined surface. Therefore, it is possible to suppress the stagnant water from staying in the water reservoir without being recirculated from the water reservoir to the reaction gas discharge communication hole, and to reliably discharge the stagnant water in the water reservoir.

  In addition, the water storage section is formed with a partition wall (for example, the partition wall 47 in the embodiment) that divides the interior into a plurality of spaces (for example, the divided water storage cylinder section 49 in the embodiment).

  If the vehicle tilts to the other side in the stacking direction and the outside air temperature is below freezing while the accumulated water is stored in the reservoir, the accumulated water freezes and ice of a size corresponding to the reservoir is formed. . Thereafter, when the vehicle returns horizontally and ice in the water storage part is discharged from the water storage part to the reaction gas discharge communication hole, ice having a large outer shape may block the reaction gas discharge communication hole. However, according to the present invention, since the interior of the water reservoir is partitioned into a plurality of spaces by the partition wall, the ice formed in the water reservoir can be subdivided and the outer shape can be reduced. As a result, it is possible to prevent the ice discharged from the water storage part from blocking the reaction gas discharge communication hole, and thus it is possible to prevent the power generation failure of the fuel cell stack.

  According to the present invention, when the vehicle is inclined to the other side in the stacking direction of the fuel cell stack, the accumulated water in the reaction gas discharge communication hole moves to the other side by gravity. Here, since the other end plate of the other side is provided with a water storage portion that communicates with the reaction gas discharge communication hole, the accumulated water that has moved to the other side is allowed to react with the reaction gas discharge communication hole by the end plate. Without being blocked inside, it moves to the water storage part and is stored. Thereby, it is possible to suppress an increase in the water level in the reaction gas discharge communication hole due to the staying water that has moved on the other side of the reaction gas discharge communication hole. Accordingly, it is possible to prevent the reaction gas discharge communication holes from being blocked by the stagnant water in the reaction gas discharge communication holes, and thus it is possible to prevent power generation failure of the fuel cell stack. Further, as in the conventional case, the gas manifold functions as a water reservoir, and the accumulated water in the reaction gas discharge communication hole can be discharged. Therefore, even when the vehicle is tilted, it is possible to prevent power generation failure of the fuel cell stack due to the staying water.

It is a perspective view of a fuel cell stack. It is a disassembled perspective view of a fuel cell stack. It is a disassembled perspective view of a unit cell. It is sectional drawing along the AA line of FIG. It is explanatory drawing when a fuel cell stack is mounted in the engine room of a fuel cell vehicle. It is explanatory drawing when a fuel cell vehicle is drive | working the bank road surface. It is explanatory drawing of the staying water in a 2nd gas exit channel | path. It is explanatory drawing when a fuel cell stack is mounted in the center tunnel of a fuel cell vehicle. It is explanatory drawing when the fuel cell vehicle is drive | working the slope surface. It is explanatory drawing of the water storage part of 2nd embodiment. It is explanatory drawing of the water storage part of 3rd embodiment. It is explanatory drawing of the water storage part of 4th embodiment. It is explanatory drawing of the water storage part of 5th embodiment. It is explanatory drawing of the water storage part of 5th embodiment when it sees from + Y side. It is explanatory drawing of an effect | action of the water storage part of 5th embodiment. It is explanatory drawing of the water storage part of 6th embodiment.

(Fuel cell stack)
The fuel cell stack according to the first embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view of the fuel cell stack 1. In FIG. 1, gas manifolds 10a to 10d through which each reaction gas flows are illustrated by two-dot chain lines.
FIG. 2 is an exploded perspective view of the fuel cell stack 1.
As shown in FIG. 1, the fuel cell stack 1 is configured by laminating a large number of unit fuel cells 2 (hereinafter referred to as “unit cells 2”) having a substantially rectangular plate shape in plan view. The fuel cell stack 1 of the present embodiment is mounted on a vehicle such as a fuel cell vehicle V (see FIG. 5). In the following description, of the two sides sandwiching the corner of the unit cell 2 formed in a substantially rectangular shape in plan view, the extending direction of the long side is the X direction, and the stacking direction of the unit cells 2 is the Y direction. The direction orthogonal to the X direction and the Y direction will be referred to as the Z direction, and will be described using an XYZ orthogonal coordinate system as necessary. Moreover, in each figure, in order to make the structure of each member easy to understand, the dimensions (particularly in the Y direction) of each member and the number of stacked unit cells 2 are appropriately changed from the actual ones.

  As shown in FIG. 2, the fuel cell stack 1 includes a stacked body 3 in which unit cells 2 composed of a membrane electrode structure 7 and a pair of separators 11 and 12 are stacked in the Y direction, and a Y direction of the stacked body 3. A pair of terminal plates 21a, 21b disposed on both sides, a pair of insulating plates 23a, 23b disposed on both sides in the Y direction of the pair of terminal plates 21a, 21b, a pair of terminal plates 21a, 21b, and a pair of insulating plates It is comprised by a pair of end plates 25a and 25b which clamp the laminated body 3 from the Y direction via 23a and 23b.

FIG. 3 is an exploded perspective view of the unit cell 2.
As shown in FIG. 3, the unit cell 2 mainly includes a membrane electrode structure 7 (corresponding to the “electrolyte membrane electrode structure” in the claims) and a pair of separators 11 and 12. The unit cell 2 is formed by the membrane electrode structure 7 being sandwiched between a pair of separators 11 and 12.
The membrane electrode structure 7 includes a solid polymer electrolyte membrane 4, an anode electrode 5 arranged on the −Y side of the solid polymer electrolyte membrane 4, and a cathode electrode 6 arranged on the + Y side of the solid polymer electrolyte membrane 4. And.
The solid polymer electrolyte membrane 4 is formed of a material obtained by impregnating perfluorosulfonic acid polymer with water, for example. The solid polymer electrolyte membrane 4 is accommodated and held in an opening of an outer frame member 7a formed in a substantially rectangular frame shape when viewed in the Y direction.

  The anode electrode 5 and the cathode electrode 6 include a porous gas diffusion layer (not shown) formed of, for example, carbon paper, and porous carbon particles having a platinum alloy supported on the surface, for example, uniformly on the surface of the gas diffusion layer. And an electrode catalyst layer (not shown) formed by being laminated. The anode electrode 5 and the cathode electrode 6 are joined to the solid polymer electrolyte membrane 4 so that the electrode catalyst layers face each other with the solid polymer electrolyte membrane 4 interposed therebetween.

  A separator 11 is provided on the −Y side of the membrane electrode structure 7, and a separator 12 is provided on the + Y side of the membrane electrode structure 7. The separators 11 and 12 are metal plate members whose outer shapes are formed in a substantially rectangular shape when viewed in the Y direction, corresponding to the outer frame member 7a of the membrane electrode structure 7, and are formed by, for example, pressing. The separators 11 and 12 have a pair of cell voltage detection output terminals 15 extending to the + Z side.

A first gas flow path 13 for supplying and discharging a hydrogen-containing gas to and from the anode electrode 5 is provided on the surface of the separator 11 facing the anode electrode 5. The first gas flow path 13 is surrounded by a seal member 13a made of, for example, rubber.
On the (+ X, + Z) side of the first gas flow path 13, a cell bridge 13 b communicating with a first gas inlet passage 31 described later is formed. Further, on the (−X, −Z) side of the first gas flow path 13, there is a cell bridge 13 c that communicates with a first gas outlet passage 32 (corresponding to “reactive gas discharge communication hole” in the claims) described later. Is formed.

A second gas flow path 14 for supplying and discharging oxygen-containing gas to and from the cathode electrode 6 is provided on the surface of the separator 12 that faces the cathode electrode 6.
Similar to the first gas flow path 13, the second gas flow path 14 is surrounded by a seal member 14 a made of, for example, rubber.
On the (−X, + Z) side of the second gas flow path 14, a cell bridge 14 b communicating with a second gas inlet passage 33 described later is formed. Further, on the (+ X, −Z) side of the second gas flow path 14, a cell bridge 14 c communicating with a later-described second gas outlet passage 34 (corresponding to “reactive gas discharge communication hole” in the claims) is formed. Has been.

  Refrigerant flow paths 16 through which cooling water (coolant) for cooling each unit cell 2 flows are formed on the surfaces of the separators 11 and 12 of the adjacent unit cells 2 facing each other. The refrigerant channel 16 is surrounded by a seal member 16a made of rubber or the like, for example, and communicates with refrigerant passages 35 and 36 described later.

The membrane electrode structure 7 and the separators 11 and 12 constituting the unit cell 2 include a first gas inlet passage 31, a first gas outlet passage 32, a second gas inlet passage 33, a second gas outlet passage 34, and a refrigerant passage 35. , 36 are formed.
The first gas inlet passage 31 is a passage for allowing a hydrogen-containing gas to pass through, and is provided at a corner of the unit cell 2 in the (+ X, + Z) direction. The first gas outlet passage 32 is a passage for allowing the hydrogen-containing gas that has been provided for power generation to pass through, and (−X, −Z) of the unit cell 2 that is a diagonal position of the first gas inlet passage 31. It is provided at the corner of the direction. The first gas inlet passage 31 communicates with the first gas passage 13 through the cell bridge 13b. The first gas outlet passage 32 communicates with the first gas flow path 13 via the cell bridge 13c. The hydrogen-containing gas flows in the order of the first gas inlet passage 31, the cell bridge 13b, the first gas passage 13, the cell bridge 13c, and the first gas outlet passage 32.

  The second gas inlet passage 33 is a passage for allowing the oxygen-containing gas to pass through, and is provided at a corner of the unit cell 2 in the (−X, + Z) direction. The second gas outlet passage 34 is a passage for allowing the oxygen-containing gas after power generation to pass therethrough, and is in the (+ X, −Z) direction of the unit cell 2 that is the diagonal position of the second gas inlet passage 33. Are provided at the corners. The second gas inlet passage 33 communicates with the second gas flow path 14 via the cell bridge 14b. The second gas outlet passage 34 communicates with the second gas flow path 14 via the cell bridge 14c. The oxygen-containing gas flows in the order of the second gas inlet passage 33, the cell bridge 14b, the second gas passage 14, the cell bridge 14c, and the second gas outlet passage 34.

  The refrigerant passages 35 and 36 are passages for allowing cooling water to pass between the first gas inlet passage 31 and the second gas outlet passage 34 and between the second gas inlet passage 33 and the first gas outlet passage 32. Are provided respectively. For example, one refrigerant passage 35 serves as an inlet passage, and the other refrigerant passage 36 serves as an outlet passage. The refrigerant passages 35 and 36 are formed on the surfaces of the separator 11 and the separator 12 facing each other. Communicated with.

  As shown in FIG. 2, a pair of terminal plates 21 a and 21 b are arranged to face each other on the + Y side and the −Y side of the stacked body 3 formed by stacking the unit cells 2. The terminal plates 21a and 21b are formed of a metal such as copper, for example, so that the outer shape in the Y direction is substantially the same as that of the laminate 3. The terminal plates 21a and 21b are electrically connected to the unit cells 2 and draw the power of the unit cells 2 to the outside via the terminals 22. Similarly to the unit cell 2, the terminal plates 21 a and 21 b have the first gas inlet passage 31, the first gas outlet passage 32, the second gas inlet passage 33, the second gas outlet passage 34, and the refrigerant passages 35 and 36. A passage is formed.

  A pair of insulating plates 23a, 23b are disposed opposite to the + Y side and the -Y side of the pair of terminal plates 21a, 21b. The insulating plates 23a and 23b are formed with an insulating material such as phenol resin, for example, so that the outer shape in the Y direction is substantially the same as that of the laminate 3. The insulating plates 23a and 23b prevent power leakage from the terminal plates 21a and 21b. Similarly to the unit cell 2, the pair of insulating plates 23a and 23b includes the first gas inlet passage 31, the first gas outlet passage 32, the second gas inlet passage 33, the second gas outlet passage 34, and the refrigerant passages 35 and 36. Each passage is formed.

A pair of end plates 25a, 25b are disposed opposite to the + Y side and the -Y side of the pair of insulating plates 23a, 23b. The end plates 25 a and 25 b are made of, for example, a metal such as iron or aluminum and have an outer shape in the Y direction larger than that of the stacked body 3.
Similarly to the unit cell 2, the + Y side end plate 25 a has the first gas inlet passage 31, the first gas outlet passage 32, the second gas inlet passage 33, the second gas outlet passage 34, and the refrigerant passages 35 and 36. Each passage is formed.

  A first gas outlet passage 32 and a second gas outlet passage 34 are formed in the −Y side end plate 25b. The first gas inlet passage 31, the second gas inlet passage 33, and the refrigerant passages 35 and 36 are not formed in the -Y side end plate 25b, and the -Y side of each passage is closed. Yes.

FIG. 4 is a cross-sectional view taken along the line AA. The first gas outlet passage 32 (see FIG. 2) and the second gas outlet passage 34 formed in the end plate 25b on the -Y side have the same structure. Accordingly, the second gas outlet passage 34 will be described below, and the description of the first gas outlet passage 32 will be omitted.
As shown in FIG. 4, the second gas outlet passage 34 of the −Y side end plate 25 b is formed by a collar 38 that covers the inner surface of the through hole 37 formed in a substantially rectangular shape when viewed in the Y direction.
The outer shape of the through hole 37 of the end plate 25 b is larger than that of the second gas outlet passage 34. On the inner side surface of the through-hole 37, a convex portion 37a projecting inward of the through-hole 37 is formed over the entire circumference at substantially the center in the Y direction.

  The collar 38 is a member having a substantially rectangular frame shape when viewed in the Y direction, and is formed of, for example, resin. The opening in the frame of the collar 38 is a second gas outlet passage 34. On the outer surface of the collar 38, a recess 38a corresponding to the protrusion 37a of the through hole 37 is formed over the entire circumference at substantially the center in the Y direction. The collar 38 is attached to the through hole 37 by fitting the convex portion 37 a of the through hole 37 and the concave portion 38 a of the collar 38.

  The pair of end plates 25a and 25b are connected by a tie rod (not shown) to hold the unit cell 2, the terminal plates 21a and 21b, and the insulating plates 23a and 23b in a stacked and compressed state. Yes. By laminating each member, the fuel cell stack 1 includes a first gas inlet passage 31, a first gas outlet passage 32, a second gas inlet passage 33, a second gas outlet passage 34, and a Y direction. Respective refrigerant passages 35 and 36 are formed.

As shown in FIG. 1, gas manifolds 10a to 10d and a pair of refrigerant pipes (not shown) are arranged on the + Y side of the + Y side end plate 25a.
The gas manifolds 10a and 10b communicate with a first gas inlet passage 31 and a first gas outlet passage 32 (see FIG. 2). The hydrogen-containing gas is introduced from the gas manifold 10a into the first gas inlet passage 31, and then passes through the first gas flow path 13 (see FIG. 3) in the unit cell 2, and from the first gas outlet passage 32 to the gas manifold. 10 b (corresponding to “a gas manifold through which the reaction gas is discharged” in the claims).

  The gas manifolds 10c and 10d communicate with the second gas inlet passage 33 and the second gas outlet passage 34 (both see FIG. 2), respectively. The oxygen-containing gas is introduced from the gas manifold 10c into the second gas inlet passage 33, and then passes through the second gas flow path 14 (see FIG. 3) in the unit cell 2, and from the second gas outlet passage 34 to the gas manifold. 10d (corresponding to “a gas manifold through which the reaction gas is discharged” in the claims).

  A catch tank (not shown) is connected to the gas manifold 10b connected to the first gas outlet passage 32 and the gas manifold 10d connected to the second gas outlet passage 34 via a branch pipe (not shown). The catch tank is provided with a water discharge valve (not shown). The catch tank stores later-described retained water generated in the first gas outlet passage 32 and the second gas outlet passage 34. The water discharge valve is opened when the amount of water stored in the catch tank exceeds a specified value, and discharges stagnant water to the outside.

  The pair of refrigerant pipes are connected to refrigerant passages 35 and 36, respectively. The refrigerant is introduced from one refrigerant pipe into the refrigerant passage 35 on the inlet side, then passes through the refrigerant flow path 16 between the unit cells 2, and is discharged from the refrigerant passage 36 on the outlet side to the other refrigerant pipe.

(Water reservoir)
As shown in FIG. 2, two reservoirs 40 (40a and 40b) are provided on the −Y side of the −Y side end plate 25b.
The water storage section 40 a that closes the first gas outlet passage 32 has a function of storing the accumulated water in the first gas outlet passage 32. The staying water in the first gas outlet passage 32 is generated by, for example, water due to condensation or generated water that has passed through the membrane electrode structure 7 (see FIG. 3) from the cathode electrode 6 side (see FIG. 3).
The water reservoir 40b that closes the second gas outlet passage 34 has a function of storing the accumulated water in the second gas outlet passage 34. The staying water in the second gas outlet passage 34 is generated on the cathode electrode 6 (see FIG. 3) side by generated water generated by the reaction of oxygen, hydrogen ions, and electrons of the oxygen-containing gas.

Hereinafter, the water storage unit 40 will be described. The water reservoir 40a that closes the first gas outlet passage 32 and the water reservoir 40b that closes the second gas outlet passage 34 have the same structure. Therefore, hereinafter, the water storage section 40b that closes the second gas outlet passage 34 will be described, and the description of the water storage section 40a that closes the first gas outlet passage 32 will be omitted.
As shown in FIG. 2, the water storage part 40b of this embodiment is formed by a water storage member 41 that closes the second gas outlet passage 34 of the end plate 25b on the -Y side.

As shown in FIG. 4, the water storage member 41 is a member formed of a metal such as aluminum or a resin, for example, and has a bottomed water storage cylinder portion 42 disposed on the −Y side of the −Y side end plate 25 b. And a flange portion 43 formed in the opening of the water storage cylinder portion 42.
The water storage cylinder portion 42 is formed in a substantially rectangular shape corresponding to the shape of the second gas outlet passage 34 as viewed in the Y direction. The water storage cylinder portion 42 is connected to and communicated with the second gas outlet passage 34. The inner side surface of the water storage cylinder portion 42 is formed along the second gas outlet passage 34 except for a -Z side surface 42a (corresponding to "the lowermost surface of the water storage portion" in the claims) described later.

  The water storage cylinder portion 42 is formed to protrude to the -Y side of the -Y side end plate 25b so as to have a predetermined depth on the -Y side on the -Y side of the -Y side end plate 25b. . The volume of the water storage cylinder portion 42 is determined by the amount of stagnant water (that is, generated water generated by the fuel cell stack 1) in the second gas outlet passage 34, and the depth on the −Y side of the water storage cylinder portion 42. The deeper the water, the more accumulated water can be stored.

  The -Z side surface 42a of the water storage cylinder portion 42 is formed substantially parallel to the XY plane. Further, in the connecting portion between the water storage section 40 and the second gas outlet passage 34, the −Z side surface 42a of the water storage cylinder section 42 (corresponding to “the lowermost surface of the water storage section” in the claims) is the second gas outlet passage 34. The −Z side end of the −Z side 34a (corresponding to the “lowermost portion of the reaction gas discharge communication hole in the direction of gravity” in the claims) is arranged at a position higher by a predetermined height h on the + Z side. Is formed. In addition, about the effect when the -Z side surface 42a of the water storage cylinder part 42 is arrange | positioned by the predetermined height h in the + Z side rather than the -Z side surface 34a in the -Y side edge part of the 2nd gas exit channel | path 34. Will be described later.

  The flange portion 43 has a substantially rectangular shape when viewed in the Y direction, and is formed to project outward from the opening edge portion on the + Y side of the water storage tube portion 42. Bolt insertion holes 43 a that penetrate in the Y direction are formed at the four corners of the flange portion 43. Bolts 29 are inserted into the respective bolt insertion holes 43a, and the water storage member 41 is fixed to the -Y side end plate 25b by fastening each bolt 29 to the -Y side end plate 25b. ing.

  A seal member 45 is disposed between the flange portion 43 and the collar 38. The seal member 45 is a member formed in a substantially annular shape when viewed in the Y direction, for example, with rubber or the like. The seal member 45 is formed in a size that can be disposed outside the second gas outlet passage 34 and inside the bolt insertion hole 43 a of the flange portion 43. By holding and fixing the water storage member 41 to the -Y side end plate 25b via the seal member 45, the accumulated water stored in the water storage unit 40b is between the water storage member 41 and the -Y side end plate 25b. Prevents leakage.

(Operation of the water reservoir)
FIG. 5 is an explanatory diagram when the fuel cell stack 1 is mounted in the engine room of the fuel cell vehicle V. FIG. FIG. 5 illustrates a state in which the fuel cell vehicle V is traveling on a substantially flat flat road R1.
FIG. 6 is an explanatory diagram when the fuel cell vehicle V is traveling on the bank road surface R2 having an inclination angle α with respect to the horizontal plane H. FIG. As shown in FIG. 6, the bank road surface R2 is a road surface that is inclined downward by an angle α from the right side of the vehicle toward the left side of the vehicle. 5 and 6, the size of the water storage section 40b is exaggerated for easy understanding.
Below, the effect | action of the water storage part 40 is demonstrated. The operation of the water storage section 40a that closes the first gas outlet passage 32 and the water storage section 40b that closes the second gas outlet passage 34 are the same. Therefore, hereinafter, only the operation of the water storage section 40b that closes the second gas outlet passage 34 will be described, and the description of the operation of the water storage section 40a that closes the first gas outlet passage 32 will be omitted.

  As shown in FIG. 5, the fuel cell stack 1 formed as described above is mounted, for example, in an engine room of a fuel cell vehicle V. In the present embodiment, the fuel cell stack 1 is configured such that the X direction coincides with the vehicle longitudinal direction, the Y direction coincides with the vehicle lateral direction, and the Z direction coincides with the vehicle vertical direction (that is, the gravity direction vertical direction). , + Y side is mounted on the right side of the vehicle, and + Z side is mounted on the upper side of the vehicle. In the following description, the vehicle front-rear direction is simply referred to as the front-rear direction, the vehicle left-right direction is simply referred to as the left-right direction, and the vehicle vertical direction is simply referred to as the vertical direction.

  As shown in FIG. 6, when the fuel cell vehicle V travels on the bank road surface R2 having the inclination angle α, the fuel cell vehicle V moves downward in the direction of gravity from the right side to the left side in accordance with the inclination angle α of the bank road surface R2. Is inclined by an angle α. At this time, the fuel cell stack 1 mounted on the fuel cell vehicle V and the second gas outlet passage 34 formed along the Y direction of the fuel cell stack 1 are also downward in the gravity direction from the + Y side to the −Y side. Inclined by an angle α.

FIG. 7 is an explanatory diagram of the staying water W in the second gas outlet passage 34. In FIG. 7, the horizontal plane H is indicated by a two-dot chain line on the polar coordinate axis.
As shown in FIG. 7, when the second gas outlet passage 34 is inclined from the + Y side toward the −Y side by an angle α downward in the gravitational direction with respect to the horizontal plane H, the staying water W in the second gas outlet passage 34. Moves in the second gas outlet passage 34 from the + Y side toward the −Y side by gravity.

Here, in the prior art, when the water level of the stagnant water W is high when the fuel cell vehicle V is inclined, there is a possibility that many unit cells 2 are blocked by the cell bridge 14b.
However, in the present embodiment, the -Y side end plate 25b is provided with a water storage section 40b that communicates with the second gas outlet passage 34 and has a depth on the -Y side. Therefore, the staying water W that has moved in the second gas outlet passage 34 from the + Y side toward the −Y side is not blocked by the −Y side end plate 25b, and is not blocked in the water storage member 41 of the water storage section 40b. Moved to and stored. Thereby, the rise in the water level of the staying water W in the second gas outlet passage 34 on the -Y side is suppressed corresponding to the volume of the staying water W stored in the water storage section 40b. A space is formed. Accordingly, the number of unit cells 2 in which the second gas outlet passage 34 and the cell bridge 14b (see FIG. 3) between the separator 12 and the cathode electrode 6 are blocked by the staying water W can be suppressed to a small number or zero. can do.

  Further, when the fuel cell vehicle V travels on the horizontal flat road R1 (see FIG. 5) after traveling on the bank road surface R2, the road surface changes from the inclined bank road surface R2 to the horizontal flat road R1, The attitude of the fuel cell vehicle V changes from an inclined state to a horizontal state. At this time, the fuel cell stack 1 mounted on the fuel cell vehicle V and the second gas outlet passage 34 formed along the Y direction of the fuel cell stack 1 are also changed from the inclined state (the state shown in FIG. 7) to the horizontal state (the state shown in FIG. 7). (The state shown in FIG. 4).

  At this time, the accumulated water W in the water storage section 40b is recirculated into the second gas outlet passage 34 due to a change in the attitude of the fuel cell vehicle V. Here, among the inner side surfaces of the water storage cylinder portion 42 of the water storage portion 40 b, the −Z side surface 42 a that is the lowest surface in the gravity direction is the lowest portion in the gravity direction at the −Y side end portion of the second gas outlet passage 34. On the + Z side with respect to the −Z side surface 34a, it is arranged at a position higher by a predetermined height h. Thereby, since the staying water W in the water storage part 40b can be suppressed from staying in the water storage part 40b, the staying water W can be discharged quickly. Therefore, the stagnant water W in the water reservoir 40b can be discharged satisfactorily.

  Thereafter, the staying water W moves from the −Y side to the + Y side in the second gas outlet passage 34, reaches the gas manifold 10d (see FIG. 1), and then branches from the gas manifold 10d (not shown). Water is stored in the catch tank. When the amount of accumulated water W in the catch tank exceeds a specified value, the accumulated water W is opened outside the fuel cell vehicle V (see FIG. 5) by opening a water discharge valve (not shown). Can be discharged.

(Modification of the first embodiment)
FIG. 8 is an explanatory diagram when the fuel cell stack 1 is mounted in a center tunnel formed on the floor of the fuel cell vehicle V. FIG. 8 illustrates a state in which the fuel cell vehicle V is traveling on a substantially flat flat road R1.
FIG. 9 is an explanatory diagram when the fuel cell vehicle V is traveling on a slope road surface R3 having an inclination angle β with respect to the horizontal plane H. FIG. As shown in FIG. 9, the slope road surface R3 is a road surface that is inclined downward by an angle β from the vehicle rear side toward the vehicle front side. In FIG. 8 and FIG. 9, the size of the water storage section 40 is exaggerated for easy understanding.

In the fuel cell stack 1 of the first embodiment, the X direction coincides with the vehicle front-rear direction, the Y direction coincides with the vehicle left-right direction, and the Z direction coincides with the vehicle up-down direction, the + X side is the vehicle rear side, the + Y side is the vehicle right side, It was mounted with the side facing the upper side of the vehicle.
In contrast, in the fuel cell stack 1 according to the modification of the first embodiment, the X direction is aligned with the vehicle left-right direction, the Y direction is aligned with the vehicle front-rear direction, and the Z direction is aligned with the vehicle up-down direction. The second embodiment is different from the first embodiment in that the vehicle is mounted so that the + Y side faces the rear side of the vehicle and the + Z side faces the upper side of the vehicle. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

  As shown in FIG. 9, when the fuel cell vehicle V travels down a slope road surface R3 having an inclination angle β, the fuel cell vehicle V moves from the rear side toward the front side corresponding to the inclination angle β of the slope road surface R3. Inclined by an angle β downward in the direction of gravity. At this time, the second gas outlet passage 34 formed along the Y direction of the fuel cell stack 1 is also inclined by the angle β downward from the + Y side toward the −Y side in the gravity direction. Accordingly, the retained water W (see FIG. 7) in the second gas outlet passage 34 moves from the + Y side toward the −Y side by gravity and then is stored in the water storage unit 40b. The rise in water level is suppressed. Therefore, similarly to the first embodiment, the staying water W prevents the second gas outlet passage 34 and the cell bridge 14b (see FIG. 3) between the separator 12 and the cathode electrode 6 from being blocked.

  Further, when the fuel cell vehicle V travels on the flat road R1 shown in FIG. 8 after traveling on the slope road surface R3, the attitude of the fuel cell vehicle V changes from the inclined state to the horizontal state. At this time, the second gas outlet passage 34 formed along the Y direction of the fuel cell stack 1 also changes from the inclined state (the state shown in FIG. 7) to the horizontal state (the state shown in FIG. 4). As a result, the accumulated water W in the water storage section 40 is recirculated into the second gas outlet passage 34 due to the change in attitude of the fuel cell vehicle V, and moves in the second gas outlet passage 34 from the −Y side toward the + Y side. After that, the fuel cell vehicle V is discharged to the outside through a catch tank (not shown) and a water discharge valve (not shown).

(effect)
According to the first embodiment and the modification of the first embodiment, when the fuel cell vehicle V is inclined toward the −Y side of the fuel cell stack 1, the residence in the first gas outlet passage 32 and the second gas outlet passage 34. The water W moves to the −Y side by gravity. Here, on the -Y side of the -Y side end plate 25b, the water storage sections 40a and 40b communicating with the first gas outlet passage 32 and the second gas outlet passage 34 are provided. The retained water W that has moved in the second gas outlet passage 34 moves to the water storage units 40a and 40b without being blocked by the end plate 25b in the first gas outlet passage 32 and the second gas outlet passage 34. To be stored. As a result, on the -Y side of the first gas outlet passage 32 and the second gas outlet passage 34, the water level in the first gas outlet passage 32 and the second gas outlet passage 34 is prevented from rising due to the moved staying water W. it can. Therefore, the first gas outlet passage 32, the second gas outlet passage 34, the first gas passage 13, and the second gas passage 14 are caused by the staying water W in the first gas outlet passage 32 and the second gas outlet passage 34. Since blockage can be prevented, it is possible to prevent power generation failure of the fuel cell stack 1. Similarly to the prior art, the + Y side gas manifolds 10b and 10d of the fuel cell stack 1 function as a water storage section by the catch tanks of the + Y side gas manifolds 10b and 10d. The accumulated water W in the first gas outlet passage 32 and the second gas outlet passage 34 can be discharged. Therefore, even when the fuel cell vehicle V is inclined, it is possible to prevent the power generation failure of the fuel cell stack 1 due to the staying water W.

(Second embodiment)
FIG. 10 is an explanatory diagram of the water storage unit 40 of the second embodiment.
In the fuel cell stack 1 of the first embodiment, the seal member 45 of the water storage section 40 is disposed between the flange portion 43 of the water storage member 41 and the collar 38, and the retained water is outside the second gas outlet passage 34. Was prevented (see FIG. 4).
In contrast, in the fuel cell stack 1 of the second embodiment, the seal member 45 of the water storage section 40 is disposed between the water storage cylinder section 42 of the water storage member 41 and the insulating plate 23b, and the second gas outlet This is different from the first embodiment in that leakage of accumulated water is prevented inside the passage 34. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

As shown in FIG. 10, the -Y side insulating plate 23b includes a cylindrical portion 24 that covers the inner surface of the through hole 37 of the end plate 25b. The cylindrical portion 24 is integrally formed with the -Y side insulating plate 23b, and is formed to protrude to the -Y side. The outer surface of the cylindrical part 24 is formed in a substantially rectangular shape as viewed in the Y direction so as to follow the inner surface of the through hole 37.
The outer surface of the water storage cylinder portion 42 of the water storage member 41 is formed in a substantially rectangular shape when viewed in the Y direction so as to be along the inner surface of the cylindrical portion 24 of the insulating plate 23b. The opening part side of the water storage cylinder part 42 is inserted and arranged in the cylindrical part 24 of the insulating plate 23b. Accordingly, the −Z side surface 42 a of the water storage cylinder portion 42 of the water storage member 41 is disposed at a position higher by a predetermined height h on the + Z side than the −Z side surface 34 a at the −Y side end portion of the second gas outlet passage 34. Is done.
A flange portion 43 is formed on the −Y side of the opening of the water storage tube portion 42 so as to project outside the water storage tube portion 42.

  A seal member 45 is disposed between the cylindrical portion 24 of the insulating plate 23 b and the opening side of the water storage cylinder portion 42 of the water storage member 41. The seal member 45 prevents the accumulated water stored in the water storage part 40b from leaking outside the fuel cell stack 1 from between the cylindrical part 24 of the insulating plate 23b and the water storage cylinder part 42 of the water storage member 41. ing.

(Effect of the second embodiment)
According to the second embodiment, since the cylindrical portion 24 is inserted and arranged in the through hole 37, the −Z side surface 42 a of the water storage cylinder portion 42 is always + Z rather than the −Z side surface 34 a of the second gas outlet passage 34. On the side, it is arranged at a position higher by a predetermined height h. Accordingly, the staying water can be prevented from staying in the water storage section 40b, and the staying water can be discharged more quickly. Furthermore, since the collar 38 can be eliminated, the fuel cell stack 1 that can prevent the occurrence of power generation failure can be formed at low cost.

(Third embodiment)
FIG. 11 is an explanatory diagram of the water reservoir 40 of the third embodiment.
In the fuel cell stack 1 of the first embodiment, the water storage section 40 is formed by the water storage member 41 (see FIG. 4).
On the other hand, the fuel cell stack 1 of the third embodiment is different from the first embodiment in that the water reservoir 40 is formed by a cylindrical portion 24 that is integrally molded with the insulating plate 23b. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

As shown in FIG. 11, the water reservoir 40b of the present embodiment is formed by a bottomed tubular portion 24 that closes the second gas outlet passage 34 and is integrally molded with the -Y side insulating plate 23b. . The cylindrical portion 24 communicates with the opening connected to the second gas outlet passage 34.
The outer surface of the cylindrical portion 24 is formed in a substantially rectangular shape as viewed in the Y direction so as to be along the inner surface of the through hole 37, and is inserted into the through hole 37 of the end plate 25 b on the −Y side. The cylindrical portion 24 is formed so as to protrude to the -Y side of the -Y side end plate 25b so as to have a predetermined depth on the -Y side on the -Y side of the -Y side end plate 25b. . The −Z side surface 24 a of the cylindrical portion 24 is disposed at a position higher by a predetermined height h on the + Z side than the −Z side surface 34 a at the −Y side end of the second gas outlet passage 34.

(Effect of the third embodiment)
According to the third embodiment, the water storage part 40 is formed by the cylindrical part 24 integrally formed with the insulating plate 23b, so that the water storage member 41, the seal member 45, and the like (both shown in FIG. 4), the water storage section 40 can be formed. Thus, since the water storage part 40 can be formed without newly providing components, the fuel cell stack 1 that can prevent the occurrence of power generation failure can be formed at low cost. Moreover, the water storage part 40 and the 2nd gas exit channel | path 34 can be integrally connected by integrally molding the water storage part 40 and the insulating plate 23b. Therefore, it is possible to reliably prevent the stagnant water from leaking between the water reservoir 40 and the second gas outlet passage 34.

(Fourth embodiment)
FIG. 12 is an explanatory diagram of the water storage section 40 of the fourth embodiment.
The fuel cell stack 1 of the first embodiment was formed such that the −Z side surface 42a, which is the lowermost surface of the water storage section 40, is substantially parallel to the XY plane (that is, the horizontal plane) (see FIG. 4).
On the other hand, the fuel cell stack 1 of the fourth embodiment is different from the first embodiment in that the −Z side surface 42a that is the lowermost surface of the water storage section 40 is formed to be inclined with respect to the XY plane. Is different. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

  As shown in FIG. 12, in the water storage portion 40b of the present embodiment, the -Z side surface 42a of the water storage cylinder portion 42 is an inclined surface that inclines from the (+ Z, -Y) side to the (-Z, + Y) side. Yes. The (+ Z, −Y) side of the −Z side surface 42a of the water storage cylinder portion 42 is formed to be disposed at a position higher by a predetermined height h on the + Z side than the −Z side surface 34a of the second gas outlet passage 34. Has been. The −Z side surface 42a of the water storage cylinder portion 42 is formed to have an inclination angle γ with respect to the −Z side surface 34a of the second gas outlet passage 34 substantially parallel to the XY plane (that is, the horizontal plane).

(Effect of the fourth embodiment)
According to the fourth embodiment, among the inner surfaces of the water storage section 40, the inclined surface that inclines the −Z side surface 42a that is the lowest surface in the direction of gravity from the (+ Z, −Y) side to the (−Z, + Y) side. By doing so, when the fuel cell vehicle V returns to the horizontal position, the accumulated water W (see FIG. 7) in the water storage section 40 can be exhausted vigorously along the inclined surface. Therefore, the staying water W is prevented from remaining in the water storage unit 40 without being recirculated from the water storage unit 40 to the first gas outlet passage 32 and the second gas outlet passage 34, and the water remaining in the water storage unit 40 is reliably discharged. it can.

(Fifth embodiment)
FIG. 13 is an explanatory diagram of the water reservoir 40 of the fifth embodiment.
FIG. 14 is an explanatory diagram of the water reservoir 40 of the fifth embodiment when viewed from the + Y side.
In the fuel cell stack 1 of the first embodiment, the water reservoir 40 is formed in a substantially rectangular shape corresponding to the shape of the second gas outlet passage 34 as viewed in the Y direction.
On the other hand, in the fuel cell stack 1 of the fifth embodiment, the water reservoir 40 is formed in a substantially rectangular shape corresponding to the shape of the second gas outlet passage 34 in the Y direction, and the water reservoir 40 This is different from the first embodiment in that the inside is partitioned into a plurality of spaces by a partition wall 47. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

  As shown in FIG. 13, the partition wall 47 is formed from the opening of the water storage cylinder 42 to the bottom inside the water storage cylinder 42. Further, as shown in FIG. 14, the partition walls 47 are arranged in a substantially lattice shape in the Y direction as viewed in the Y direction, and two partition walls 47 in the X direction and the Z direction, respectively. By the partition wall 47, the interior of the water storage cylinder portion 42 is partitioned into a plurality of (9 in this embodiment) spaces (hereinafter referred to as “divided water storage cylinder portions 49”) that open in the + Y direction. Each divided water storage cylinder portion 49 is formed so that the outer shape in the Y direction is smaller than the outer shape of the second gas outlet passage 34.

(Operation of the water storage unit 40 of the fifth embodiment)
FIG. 15 is an explanatory diagram of the operation of the water storage unit 40 of the fifth embodiment. In addition, in FIG. 15, illustration of components other than the water storage cylinder part 42 is abbreviate | omitted in order to make description easy to understand.
When the fuel cell vehicle V stops in a state of being inclined on the bank road surface R2 (see FIG. 6) having an inclination angle α, the accumulated water W in the second gas outlet passage 34 is + Y in the second gas outlet passage 34 due to gravity. It moves toward the -Y side from the side and is stored inside the water storage cylinder part 42 (see FIG. 7). Further, when the outside air temperature falls below freezing point while the accumulated water W is stored in the water storage cylinder portion 42, the accumulated water W is frozen, and the ice I having a shape corresponding to the inner shape of the water storage cylinder portion 42 (FIG. 15) is formed. Here, since the inside of the water storage cylinder part 42 is partitioned by the partition wall 47 into the divided water storage cylinder part 49, the ice I formed by freezing the accumulated water W has a shape corresponding to the divided water storage cylinder part 49. Formed. Note that the length L1 of the ice I in the Y direction (see FIG. 15) corresponds to the depth of the water storage cylinder portion 42.

Thereafter, when the attitude of the fuel cell vehicle V changes from the inclined state to the horizontal state (see FIG. 5), as shown in FIG. 15, the substantially block-shaped ice formed in the divided water storage cylinder portion 49 (see FIG. 14). I is discharged into the second gas outlet passage 34 (see FIG. 13) on the + Y side.
Here, each divided water storage tube portion 49 is formed so that the outer shape in the Y direction is smaller than the outer shape of the second gas outlet passage 34, so that the outer shape of the ice I in the Y direction is also the second gas outlet passage 34. Is formed smaller than the outer shape of the second gas outlet passage 34. Therefore, the ice I is discharged into the second gas outlet passage 34 without closing the second gas outlet passage 34.

(Effect of the fifth embodiment)
According to the fifth embodiment, since the interior of the water storage section 40 is partitioned into the plurality of divided water storage cylinder sections 49 by the partition wall 47, the ice I formed in the water storage section 40 can be subdivided and the outer shape can be reduced. Thereby, it is possible to prevent the ice I discharged from the water storage section 40 from closing the first gas outlet passage 32 and the second gas outlet passage 34, and thus it is possible to prevent the occurrence of power generation failure of the fuel cell stack 1. . The depth of the water storage cylinder portion 42 is preferably set so that the length L1 of the ice I in the Y direction is shorter than the minimum width of the second gas outlet passage 34 when viewed in the Y direction. Thereby, it is possible to reliably prevent the ice I from closing the first gas outlet passage 32 and the second gas outlet passage 34.

(Sixth embodiment)
FIG. 16 is an explanatory diagram of the water reservoir 40 of the sixth embodiment. FIG. 16 illustrates a state in which the fuel cell vehicle V is traveling on the bank road surface R2 (see FIG. 6) having an inclination angle α with respect to the horizontal plane H.
The fuel cell stack 1 of the first embodiment is formed such that the + Z side surface of the water storage cylinder portion 42 forming the water storage portion 40 is substantially flush with the + Z side surface of the second gas outlet passage 34 (FIG. 4). reference).
On the other hand, in the fuel cell stack 1 of the sixth embodiment, the + Z side surface of the water storage cylinder portion 42 forming the water storage portion 40 is arranged on the + Z side with respect to the + Z side surface of the second gas outlet passage 34. This is different from the first embodiment. In addition, description is abbreviate | omitted about the component similar to 1st embodiment.

As shown in FIG. 16, the + Z side surface 42 b of the water storage cylinder portion 42 is disposed at a position higher by a predetermined height k on the + Z side than the + Z side surface at the −Y side end of the second gas outlet passage 34. . Thereby, since a space is formed on the + Z side with respect to the + Z side surface of the second gas outlet passage 34 in the water storage cylinder portion 42, the volume of the water storage cylinder portion 42 is ensured to be larger on the + Z side than in the first embodiment.
According to the sixth embodiment, since the accumulated water W can be stored also on the + Z side of the water storage cylinder portion 42, the rise in the water level of the accumulated water W is further suppressed, and the generation failure of the fuel cell stack 1 is prevented. it can. In particular, when the space on the -Y side of the water storage section 40 is limited and the depth of the water storage cylinder section 42 in the Y direction is restricted, it is necessary to secure a large volume of the water storage cylinder section 42. The form is effective.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  In each embodiment, both the first gas outlet passage 32 and the second gas outlet passage 34 are provided with the water storage portions 40a and 40b, respectively, but one of the first gas outlet passage 32 and the second gas outlet passage 34 is provided. The water storage units 40a and 40b may be provided only in the case.

  The mounting direction of the fuel cell stack 1 with respect to the fuel cell vehicle V is not limited to the first embodiment and the modification of the first embodiment. The water storage section 40 is located below the first gas outlet passage 32 and the second gas outlet passage 34 in the direction of gravity when the fuel cell vehicle V tilts in a direction in which the fuel cell vehicle V can tilt when traveling and stopping. What is necessary is just to be arrange | positioned. As a result, the water storage section 40 can store the accumulated water W in the first gas outlet passage 32 and the second gas outlet passage 34 when the fuel cell vehicle V is tilted, so that the increase in the water level of the retained water W is suppressed, and the fuel It is possible to prevent the power generation failure of the battery stack 1.

DESCRIPTION OF SYMBOLS 1 ... Fuel cell stack 3 ... Laminated body 7 ... Membrane electrode structure 10b, 10d ... Gas manifold (gas manifold from which reaction gas is discharged)
11, 12 ... separators 25a, 25b ... end plate 32 ... first gas outlet passage (reactive gas discharge passage)
34 ... Second gas outlet passage (reactive gas discharge passage)
34a ...- Z side surface (the lowest part in the gravity direction of the reaction gas discharge communication hole)
40 ... Water storage parts 24a, 42a ...- Z side surface (lowermost surface in the gravity direction of the water storage part)
47 ... Partition wall 49 ... Divided water storage cylinder (space)
V ... Fuel cell vehicle (vehicle)

Claims (4)

A fuel cell stack mounted on a vehicle,
Comprising a laminate in which an electrolyte membrane electrode structure and a separator are laminated;
A pair of end plates are arranged at both ends in the stacking direction of the stack,
The laminated body is provided with a reaction gas discharge communication hole for discharging the reaction gas used for power generation along the lamination direction,
Of the pair of end plates, an end plate disposed on one side in the stacking direction is provided with a gas manifold that communicates with the reaction gas discharge communication hole and discharges the reaction gas.
Of the pair of end plates, the end plate disposed on the other side in the stacking direction is provided with a water storage section that communicates with the reactive gas discharge communication hole. The fuel cell stack according to claim 1, wherein
The lowermost surface in the gravity direction of the inner surface of the water reservoir is located above the lowermost portion in the gravitational direction at the other end of the reaction gas discharge communication hole connected to the water reservoir. A fuel cell stack. The fuel cell stack according to claim 1 or 2,
The fuel cell stack, wherein the lowermost surface in the gravitational direction among the inner side surfaces of the water reservoir is inclined downward in the gravitational direction from the other side toward the one side. The fuel cell stack according to any one of claims 1 to 3,
A partition wall for partitioning the interior into a plurality of spaces is formed in the water storage section.

Images