JP5286780B2 - Fuel cell stack - Google Patents

Description

  The present invention relates to a fuel cell stack, and more particularly to a technique for improving the drainage of the fuel cell stack.

  In the energy field in recent years, fuel cells have attracted attention as natural energy-efficient and high-efficiency energy conversion devices. FIG. 6 is a partial schematic cross-sectional view showing a configuration of a general fuel cell stack 100. As shown in FIG. 6, a general fuel cell stack 100 includes a fuel cell stack 72 in which a plurality of fuel cells 70 are stacked, and end plates 74 a and 74 b provided at both ends of the fuel cell stack 72 in the stacking direction. The gas supply pipe 76 and the gas discharge pipe 78 are connected to the fuel cell stack 72 through the end plates 74a and 74b. The gas supply passage 76a inside the gas supply pipe 76 is connected to and communicates with a gas supply manifold 80 formed through in the stacking direction of the fuel cell stack 72, and the gas discharge passage 78a inside the gas discharge pipe 78 is connected to the fuel cell. It is connected to and communicates with a gas discharge manifold 82 formed so as to penetrate in the stacking direction of the stacked body 72.

  When the fuel gas supplied to the fuel electrode side of the fuel cell 70 is hydrogen gas and the oxidant gas supplied to the oxidation electrode side is oxygen gas, hydrogen ions are generated on the fuel electrode side during power generation of the fuel cell 70. The hydrogen ions pass through the electrolyte membrane of the fuel cell 70, and the electrons reach the oxidation electrode side through an external circuit. On the oxidation electrode side, a reaction in which hydrogen ions, electrons, and oxygen gas react to generate moisture is performed.

  The oxidant gas supplied to the fuel cell 70 is humidified by a humidifier provided in the fuel cell stack in order to impart ion conductivity to the electrolyte membrane of the fuel cell 70. However, since the temperature of the oxidant gas supplied to the fuel cell stack 72 is lower than the temperature of the fuel cell stack 72 during power generation, water contained in the oxidant gas may condense and liquid water may be generated. is there. Moreover, the water produced | generated by the electrochemical reaction in each fuel cell 70 may also condense, and it may become liquid water. These liquid waters (simply referred to as “water” hereinafter) flow into the gas discharge manifold 82 along with the waste oxidant gas, and then flow out of the system via the gas discharge manifold 82 and the gas discharge passage 78a. To be discharged.

In this case, in the fuel cell stack 100, it is desired that water is discharged well from the fuel cell stack 70 to the outside of the system. This is because, if water is accumulated in the gas exhaust manifold 82, may cause the power generation performance degradation is a factor that inhibits the waste unloading of the waste oxygen-containing gas from the fuel cell stack 72, also decreases the environmental temperature This is because when the water accumulated in the gas discharge manifold 82 is frozen, the manifold may be blocked.

  For example, Patent Document 1 discloses a fuel cell stack in which a lower surface of a gas discharge manifold in a fuel cell stack is formed to be inclined downward toward an exhaust direction downstream to an end plate connecting portion. In this fuel cell stack, the through hole of the end plate connected to the gas discharge manifold is formed in the horizontal direction, and a water reservoir is provided close to the end plate in the gas discharge pipe connected to the end plate. The water discharged through the manifold is once stored in the water reservoir, and then drained downward by opening the electromagnetic valve.

  Further, Patent Document 2 describes that drainage from the fuel cell stack is improved by providing a downward slope to the oxidant gas pipe connected to the end plate of the fuel cell stack.

JP 2003-177871 A JP 2004-134130 A

  However, in the fuel cell of Patent Document 1, since the lower surface of the through hole of the end plate connected to the gas discharge manifold in the fuel cell stack is formed along the horizontal direction, for example, a vehicle on which this fuel cell is mounted is on a slope. When the lower surface of the gas exhaust manifold in the fuel cell stack becomes horizontal when the vehicle is stopped or parked, the gas discharge passage constituted by the through hole of the end plate is in an upward inclined state. Then, it is conceivable that water can be accumulated at the boundary between the gas discharge manifold of the fuel cell stack and the through hole of the end plate, and the accumulated water flows back into the gas discharge manifold.

  In addition, in the fuel cell of Patent Document 2, although the oxidant gas pipe connected to the end plate is inclined downward, the gas discharge manifold in the fuel cell stack and the through hole of the end plate connected to the gas discharge manifold As described above with respect to Patent Document 1, water accumulated at the boundary between the gas discharge manifold of the fuel cell stack and the through hole of the end plate enters the gas discharge manifold. It is thought that it will flow backward.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a fuel cell stack that can reliably discharge water that has flowed out through a gas discharge manifold in the fuel cell stack outside the fuel cell stack with a simple configuration without being obstructed by an end plate. Is to provide.

The fuel cell stack according to the present invention, through a plurality of fuel cells and fuel cell stack formed by stacking, and the end plate which is provided at opposite ends in the stacking direction of the fuel cell stack, the stacking direction of the fuel cell stack a gas supply manifold that is, the fuel gas discharge manifold stacked is the direction in the through formation of the cell stack, and the gas discharge passage communicating with the gas exhaust manifold formed through said end plate, fuel Ru includes a battery The end plate in which the gas discharge passage is formed has a stack-facing surface facing the fuel cell stack and a mounting surface on the opposite side to which piping is mounted. When the fuel cell stack is installed so that the surface is along the vertical direction, the stacked body facing surface has a first inclination angle with respect to the vertical direction. When the fuel cell stack is installed so that the mounting surface of the end plate on which the gas discharge path is formed is oriented along the vertical direction, the fuel cell stack is formed so as to face obliquely upward. the said gas discharge manifold formed through along the stacking direction of Ri Do a downward slope toward the first inclination angle with the gas discharge direction downstream side with respect to the horizontal direction, the gas discharge passage in the horizontal direction with second inclination angle greater than the first inclination angle, wherein the benzalkonium such a downward slope toward the gas discharge direction downstream side against.

In the fuel cell stack according to the present invention, it is preferable that the lower surface of the gas discharge passage is formed linearly between the stacked body facing surface of the end plate and the mounting surface .

  The fuel cell stack according to the present invention further includes a gas discharge pipe connected to the end plate and communicating with the gas discharge passage, and the gas discharge pipe has a downward slope toward the downstream side in the gas discharge direction with respect to the horizontal direction. It is preferable to have a third inclination angle, and the third inclination angle is set to be larger than the second inclination angle.

  In the fuel cell stack according to the present invention, the inner surface of the gas discharge passage is preferably formed or coated with a hydrophilic material.

  Furthermore, in the fuel cell stack according to the present invention, the lower surface of the gas discharge passage is positioned below the lower surface of the gas discharge manifold at the connection portion between the gas discharge manifold of the fuel cell stack and the gas discharge passage of the end plate. A step may be provided.

  According to the fuel cell stack of the present invention, the gas discharge manifold has a first inclination angle that is downwardly inclined toward the downstream side in the gas discharge direction with respect to the horizontal direction, and the gas discharge passage is in the horizontal direction. For example, a vehicle equipped with a fuel cell stack has a second inclination angle that is downwardly inclined toward the downstream side in the gas discharge direction, and the second inclination angle is set to be larger than the first inclination angle. Even when the fuel cell stack is parked or parked on a slope, the gas exhaust passage of the end plate can be maintained in a downwardly inclined state even when the lower surface of the gas exhaust manifold in the fuel cell stack becomes horizontal. As a result, the water discharged from the gas discharge manifold of the fuel cell stack can be reliably discharged to the gas discharge passage without collecting at or near the boundary between the gas discharge manifold and the gas discharge passage. And back flow into the gas discharge manifold can be suppressed with a simple configuration.

  Embodiments of a fuel cell stack according to the present invention will be described below in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the purpose, purpose, and specifications.

  FIG. 1 is a block diagram showing a schematic configuration of a fuel cell system 1 including a fuel cell stack 10 according to an embodiment of the present invention. The fuel cell system 1 includes a fuel cell stack 10, a voltage converter 12, an inverter 14, a motor 16, a smoothing capacitor 18, a humidifier 20, a diluter 22, a fuel gas supply unit 24, an oxidant gas supply unit 26, and a refrigerant circulation. A portion 28 is included.

  The fuel cell stack 10 generates power by an electrochemical reaction through an electrolyte membrane of, for example, hydrogen, which is a fuel gas, and, for example, oxygen, which is an oxidant gas, and outputs a DC voltage to the voltage converter 12. The voltage converter 12 boosts the DC voltage supplied from the fuel cell stack 10 as necessary, and supplies the boosted high-voltage DC voltage to the inverter 14 via the smoothing capacitor 18. The inverter 14 converts the high-voltage DC voltage supplied from the voltage converter 12 into a three-phase AC voltage and applies it to, for example, a three-phase synchronous AC motor 16. The driving force of the motor 16 that is rotated by voltage application from the inverter 14 is used for driving wheels of a vehicle such as an automobile.

  Hydrogen is supplied to the fuel cell stack 10 as a fuel gas from the fuel gas supply unit 24. The fuel gas supply unit 24 can be composed of, for example, a high-pressure hydrogen tank. On the other hand, air containing oxygen as an oxidizing gas is taken in from the atmosphere by the oxidant gas supply unit 26 and supplied to the fuel cell stack 10 via the humidifier 20. In order to promote the electrochemical reaction in the fuel cell stack 10, the air is sufficiently humidified when passing through the humidifier 20.

  The waste hydrogen gas that has been subjected to an electrochemical reaction with oxygen in the fuel cell stack 10 is sent from the fuel cell stack 10 to the diluter 22. On the other hand, the waste air that has been subjected to the electrochemical reaction with hydrogen in the fuel cell stack 10 is discharged from the fuel cell stack 10 together with the water generated by the electrochemical reaction, and passes through the humidifier 20. And sent to the diluter 22. In the humidifier 20, the produced water contained in the waste air is collected by the porous body incorporated therein and reused for humidifying the supply air. In the diluter 22, the waste hydrogen gas is sufficiently mixed and diluted with waste air, and then exhausted out of the system. Since the waste hydrogen gas contains unused high-concentration hydrogen, it may be circulated and supplied to the fuel cell stack 10.

  The refrigerant circulation unit 28 circulates, for example, LLC (Long Life Coolant) as a cooling medium in the fuel cell stack 10 in order to cool the fuel cell stack 10 that is heated by an electrochemical reaction.

  FIG. 2 is a perspective view of the fuel cell stack 10, and FIG. 3 is a side view of one end portion of the fuel cell stack 10. In FIG. 3 (the same applies to FIGS. 4 and 5), the upper side of the paper is the upper side in the vertical direction, and the lower side of the paper is the lower side in the vertical direction. The fuel cell stack 10 is accommodated in a sheet metal stack case (not shown) and can be mounted or installed in an automobile or the like.

  The fuel cell stack 10 is a cell stack (fuel cell stack) configured by stacking a plurality of fuel cell cells 30 each having an anode electrode, an electrolyte membrane, and a cathode electrode sandwiched by separators and connecting them in series. 38. The cell stack 38 is sandwiched between a pair of current collecting plates 32a and 32b, insulating plates 34a and 34b, and end plates 36a and 36b provided at both ends in the stacking direction indicated by arrow B, respectively. The electric power generated by the plurality of fuel cells 30 constituting the cell stack 38 is output from the pair of current collector plates 32a and 32b.

  For example, each end plate 36a, 36b formed of a stainless steel plate is connected to the upper and lower portions by two belt-like members 40, and the cell laminate is connected to the end plates 36a, 36b by these belt-like members 40. A tensile force for clamping 38 is applied. The end portions of the belt-like members are fixed to the end plates 36a and 36b by appropriate fixing means such as screws.

  One end plate 36a of the end plates 36a, 36b has a stacked body facing surface 37a facing the cell stacked body 38 via the current collector plate 32a and the insulating plate 34a, and a system component mounting surface 37b on the opposite side thereof. . The end plate 36a has a trapezoidal side surface, and when the system component mounting surface 37b is disposed along the vertical direction, a predetermined amount with respect to the system component mounting surface 37b is set so that the stacked body facing surface 37a faces slightly upward. Are formed with an inclination angle θ1.

  The end plate 36a has a fuel gas supply passage 42a, an oxidant gas supply passage 44a, a cooling medium supply passage 46a, and a fuel gas discharge passage, each of which has a thickness direction, that is, a hole that is formed through both ends 37a and 37b. 42b, an oxidant gas discharge passage 44b and a cooling medium discharge passage 46b. Each of the passages 42a, 42b, 44a, 44b, 46a, 46b is formed in a vertical arrangement of three on each side of the end plate 36a in the horizontal direction.

  In the cell stack 38, a fuel gas supply formed so as to penetrate the cell stack 38 in the stacking direction in order to supply the fuel gas and the oxidant gas to the anode side electrode and the cathode side electrode of each fuel battery cell 30. A manifold 52a and an oxidizing gas supply manifold 54a are provided. The fuel gas supply manifold 52a and the oxidant gas supply manifold 54a are respectively connected to the fuel gas supply passage 42a and the oxidant gas supply passage 44a of the end plate 36a through through holes formed in the current collecting plate 32a and the insulating plate 34a. Communicate.

  Further, in the cell stack 38, a fuel gas discharge formed so as to penetrate in the cell stacking direction in order to discharge the waste fuel gas and the waste oxidant gas from the anode side electrode and the cathode side electrode of each fuel battery cell 30. A manifold 52b and an oxidant gas discharge manifold 54b are provided. The fuel gas discharge manifold 52b and the oxidant gas discharge manifold 54b are respectively connected to the fuel gas discharge passage 42b and the oxidant gas discharge passage 44b of the end plate 36a through through holes formed in the current collecting plate 32a and the insulating plate 34a. Communicate.

  Furthermore, in the cell stack 38, in order to suppress a temperature rise due to heat generated by the electrochemical reaction of the fuel cell 30, a cooling medium is flowed from the outside of the fuel cell stack 10 into each fuel cell 30. The cooling medium supply manifold 56a and the cooling medium discharge manifold 56b for supplying and discharging the cooling medium are also formed through the cell stack 38 in the stacking direction. The cooling medium supply manifold 56a and the cooling medium discharge manifold 56b communicate with the cooling medium supply passage 46a and the cooling medium discharge passage 46b of the end plate 36a through through holes formed in the current collector plate 32a and the insulating plate 34a, respectively. ing. In FIG. 2, the thick black arrow indicates the fuel gas flow direction, the thick white arrow indicates the oxidant gas flow direction, and the hatched thick arrow indicates the coolant flow direction.

  Six pipes 58 corresponding to the passages 42a, 42b, 44a, 44b, 46a, 46b are attached to the system component attachment surface 37b of the end plate 36a. Each pipe 58 can be made of resin or metal, and is fixed to the end plate 36a by screwing a flange portion 59 provided integrally at the end portion. Further, a pump 48 is attached to a substantially central portion of the system component attachment surface 37b of the end plate 36a by a method such as screwing. These piping 58, pump 48, and the like constitute system components.

  As shown in FIG. 2, in the present embodiment, three passages 42a, 42b, 44a, 44b, 46a, 46b are vertically arranged on the left and right sides of the end plate 36a. The arrangement is not limited to this, and can be appropriately changed according to the design of the manifolds 52a, 52b, 54a, 54b, 56a, and 56b of the fuel gas, the oxidant gas, and the cooling medium in the fuel cell stack 10. For example, the cooling medium manifolds 56a and 56b and the passages 46a and 46b may be formed above and below the cell stack 38 and the end plate 36a. Further, each manifold 52a, 52b, 54a, 54b, 56a, 56b only needs to pass through the cell stack 38 in the stacking direction of the fuel cells 30, and may not necessarily be formed in a straight line. Or you may incline with respect to the lamination direction (arrow B direction).

  Hydrogen, which is the fuel gas supplied from the fuel gas supply passage 42a of the end plate 36a to the fuel gas supply manifold 52a via the pipe 58, is the surface of the anode side electrode (power generation surface) in each stacked fuel cell 30. ) To the side (from the right side to the left side in FIG. 2). The anode side electrode is configured to contain a catalyst, and while flowing along the surface of the anode side electrode, a part of hydrogen is activated by the catalyst to release electrons and become hydrogen ions, which pass through the electrolyte membrane. Move to the cathode electrode. Electrons released by the ionization of hydrogen become electric power generated by the fuel cell 30. Hydrogen that has not been used for power generation (that is, not ionized) in the fuel cell 30 passes through the fuel gas discharge manifold 52b and the fuel cell stack 10 from the fuel gas discharge passage 42b of the end plate 36a through the pipe 58. Discharged outside.

  Air containing oxygen, which is an oxidant gas supplied from the oxidant gas supply passage 44a of the end plate 36a to the oxidant gas supply manifold 54a via the pipe 58, is laid in each stacked fuel battery cell 30. It flows from the left side to the right side in FIG. 2 along the surface of the cathode side electrode. The cathode side electrode is configured to include a catalyst, and while flowing along the surface of the cathode side electrode, a part of oxygen in the air is activated by the catalyst to become oxygen ions, and permeates the electrolyte membrane to reach the cathode side electrode. Chemical reaction with the hydrogen ions that have moved from the water produces water. The air that flows along the cathode side electrode in the fuel cell 30 passes through the oxidant gas discharge manifold 54b together with the reaction product water to the fuel from the oxidant gas discharge passage 44b of the end plate 36a through the pipe 58. It is discharged out of the battery stack 10.

  Further, the cooling medium supplied from the cooling medium supply passage 46a of the end plate 36b to the cooling medium supply manifold 56a via the pipe 58 passes through the flow path formed between the stacked fuel cell units 30 ( The fuel cell 30 that flows from the left side to the right side in FIG. 2 and rises in temperature due to heat generated by the internal electrochemical reaction is cooled. Thereafter, the cooling water is discharged from the cooling medium discharge passage 46b of the end plate 36a to the outside of the fuel cell stack 10 via the pipe 58 via the cooling medium discharge manifold 56b.

  FIG. 4 is a partial cross-sectional view showing the inclination relationship among the manifold in the cell stack 38, the gas passage in the end plate 36 a, and the pipe 58 in the fuel cell stack 10 as a representative example for oxidant gas discharge. As described above, the end plate 36a is formed such that the stacked body facing surface 37a has an inclination angle θ1 with respect to the system component mounting surface 37b. Therefore, when the fuel cell stack 10 is installed so that the system component mounting surface 37b of the end plate 36a is along the vertical direction, the cell stack that is mounted on the stacked body facing surface 37a via the insulating plate 34a and the current collector plate 32a. The lower surface of the oxidant gas discharge manifold 54b penetratingly formed along the cell stacking direction in the body 38 is inclined downward toward the downstream side of the gas discharge direction (arrow C direction) with an inclination angle θ1 with respect to the horizontal direction. It has become. As a result, the water contained in the waste oxidizing gas flows along the lower surface 60 of the downwardly inclined discharge manifold 54b, so that the cell stack 38 is easily drained.

  The lower surface 62 of the oxidant gas discharge passage 44b of the end plate 36a connected to the oxidant gas discharge manifold 54b also has an inclination angle θ2 with respect to the horizontal direction so as to be inclined downward toward the downstream side in the gas discharge direction. However, the inclination angle θ2 is set larger than the inclination angle θ1 of the oxidant gas discharge manifold 54b. Further, in this configuration, the lower surface of the flow path from the oxidant gas discharge manifold 54b to the outlet of the oxidant gas discharge passage 44b of the end plate 36a (opening on the system component mounting surface 37b) descends generally or entirely. It has a gradient. In this manner, for example, when the vehicle on which the fuel cell stack 10 is mounted stops or parks on a slope, the end surface of the oxidant gas discharge manifold 54b in the cell stack 38 becomes horizontal even when the lower surface 60 becomes horizontal. The lower surface 62 of the oxidant gas discharge passage 44b of the plate 36a can be maintained in a descending gradient state. As a result, the water discharged from the oxidant gas discharge manifold 54b of the cell stack 38 does not collect at the boundary portion or the connection portion 64 between the oxidant gas discharge manifold 54b and the oxidant gas discharge passage 44b or in the vicinity thereof. It can surely flow into the oxidant gas discharge passage 44b and be drained through the pipe 58, and backflow into the oxidant gas discharge manifold 54b can be suppressed with a simple configuration.

  The lower surface 68 in the pipe 58 connected to the oxidant gas discharge passage 44b of the end plate 36a also has an inclination angle θ3 with respect to the horizontal direction so as to become a downward gradient toward the downstream side in the gas discharge direction. The inclination angle θ3 is set to be larger than the inclination angle θ2 of the lower surface 62 of the oxidant gas discharge passage 44b. By doing in this way, the drainage property from the fuel cell stack 10 can be made better and more reliable. Further, the piping configuration is simplified and the cost is reduced as compared with the case where a water reservoir or a solenoid valve is provided in the piping 58.

  Here, the inclination relationship of the oxidant gas discharge manifold 54b, the discharge passage 44b, and the piping 58 has been described as an example. However, the same inclination relationship applies to the fuel gas discharge manifold 52b, the discharge passage 42b, and the piping 58. Is given. Further, the manifolds 52a and 54a for supplying the fuel gas and the oxidant gas, the supply passages 42a and 44a, and the pipe 58 may also contain the condensed water of the humidified water, etc. It is desirable to be configured.

  In FIG. 3, the cooling medium supply and discharge manifolds 56a and 56b, the passages 46a and 46b, and the piping 58 are also shown to have the above-described inclination relationship. This is because it is preferable to configure in this way, and the above-described inclination relationship does not necessarily have to be satisfied.

  The through holes constituting the gas discharge passages 42b, 44b and the like of the end plate 36a are formed by a processing method such as cutting, punching, molding, etc., but the lower surface in the passage is between both end surfaces 37a, 37b of the end plate 36a. It is preferable to form it linearly. This is for facilitating processing such as cutting and smoothing the flow of water toward the pipe 58.

  Moreover, it is preferable that the inner surfaces including at least the lower surface of the gas discharge passages 42b and 44b are made of a hydrophilic material. This can impart propulsive force to the water flowing into the passages 42b and 44b from the discharge manifolds 52b and 54b due to the hydrophilicity. As a result, for example, the pipe 58 is made of a material having water repellency. 58 has an advantage that water is easily introduced. In this case, the inner surfaces of the passages 42b and 44b may be coated with a hydrophilic material (for example, gold), or the end plate 36a itself may be coated with a hydrophilic material (for example, a metal oxide such as silica or titanium oxide). May be formed.

  Incidentally, in the above embodiment, the gas discharge manifolds 52b and 54b, the gas discharge passages 42b and 44b, and the flow paths in the pipe 58 are connected without any step, but as shown in FIG. While satisfying the magnitude relationship between θ1, θ2, and θ3, a step d may be provided so that the downstream flow path lower surface is positioned below in each of the connection portions 64 and 65. By doing in this way, it can prevent that a reverse level | step difference is formed in each connection part 64 and 65 by manufacturing tolerance, the dispersion | variation at the time of an assembly, etc., and it becomes a drainage resistance part.

  In the fuel cell stack 10 of the above-described embodiment, one end plate 36a is configured by a plate-like member having a trapezoidal side surface, but is not limited to this, and the end plate in the present invention has a constant thickness. You may be comprised with the plate-shaped member of.

  In the fuel cell stack 10 described above, the fuel gas, the oxidant gas, and the cooling medium are moved in and out from the same end plate. However, in the present invention, the fuel gas or the like is started from one (or the upper side) end plate. This is also applicable to a fuel cell stack of the type that supplies the gas and discharges it from the other (or lower) end plate.

1 is a schematic configuration diagram of a fuel cell system including a fuel cell stack according to an embodiment of the present invention. It is a perspective view of a fuel cell stack. It is a side view of the one side edge part of a fuel cell stack. It is a fragmentary sectional view which shows the inclination relation of the manifold for exhausting oxidant gas in a fuel cell stack, the gas path in an end plate, and piping. It is a figure which shows the modification of FIG. It is a figure which shows an example of the conventional fuel cell stack.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Fuel cell system, 10 Fuel cell stack, 12 Voltage converter, 14 Inverter, 16 Motor, 18 Smoothing capacitor, 20 Humidifier, 22 Diluter, 24 Fuel gas supply part, 26 Oxidant gas supply part, 28 Refrigerant circulation part , 30 Fuel cell, 32a, 32b Current collector plate, 34a, 34b Insulating plate, 36a, 36b End plate, 37a Laminated body facing surface, 37b System component mounting surface, 38 cell laminated body, 40 Band member, 42a Fuel gas supply Passage, 42b fuel gas discharge passage, 44a oxidant gas supply passage, 44b oxidant gas discharge passage, 46a cooling medium supply passage, 46b cooling medium discharge passage, 48 pump, 58 piping, 59 flange, 60 lower surface, 62 lower surface, 62 boundary or connection, 65 connection, 68 bottom surface, d step, θ1, θ2, θ3 Tilt angle.

Claims (5)

A fuel cell stack in which a plurality of fuel cells are stacked, end plates provided at both ends in the stacking direction of the fuel cell stack, a gas supply manifold formed so as to penetrate in the stacking direction of the fuel cell stack, and the fuel a gas exhaust manifold formed through the stacking direction of the cell stack, and the gas discharge passage communicating with the gas exhaust manifold formed through said end plate, a fuel cell stack Ru provided with,
The end plate in which the gas discharge passage is formed has a stacked body facing surface facing the fuel cell stacked body and a mounting surface on the opposite side to which piping is mounted, and the mounting surface is in a vertical direction. When the fuel cell stack is installed so as to be along, the stacked body facing surface forms a first inclination angle with respect to the vertical direction so as to face obliquely upward,
When the fuel cell stack is installed so that the mounting surface of the end plate in which the gas discharge path is formed is along the vertical direction, the gas formed so as to penetrate along the stacking direction of the fuel cell stack The discharge manifold has a downward slope toward the downstream side in the gas discharge direction with the first inclination angle with respect to the horizontal direction, and the gas discharge passage has a second inclination angle larger than the first inclination angle with respect to the horizontal direction. a fuel cell stack, wherein the benzalkonium such a downward slope toward the gas discharge direction downstream side with. The fuel cell stack according to claim 1, wherein
A lower surface of the gas discharge passage is formed in a straight line between the stacked body facing surface of the end plate and the mounting surface . The fuel cell stack according to claim 1 or 2,
A gas discharge pipe connected to the end plate and communicating with the gas discharge passage has a third inclination angle that is downwardly inclined toward the downstream side in the gas discharge direction, and the third inclination angle is the second inclination angle. A fuel cell stack characterized by being set larger than a corner. The fuel cell stack according to claim 3,
A fuel cell stack, wherein an inner surface of the gas discharge passage is formed or coated with a hydrophilic material. The fuel cell stack according to any one of claims 1 to 4,
A step is provided at the connecting portion between the gas discharge manifold of the fuel cell stack and the gas discharge passage of the end plate so that the lower surface of the gas discharge passage is located below the lower surface of the gas discharge manifold. Fuel cell stack.

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