JP4673877B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system, and more particularly to a drainage technique for a fuel cell system.

  In the energy field in recent years, a fuel cell has attracted attention as a highly efficient energy conversion device. FIG. 12 is a partial schematic cross-sectional view showing a configuration of a general fuel cell system. As shown in FIG. 12, a general fuel cell system includes a fuel cell stack 72 in which at least one fuel cell 70 is stacked, end plates 74a and 74b provided at both ends in the stacking direction, end plates 74a, A gas introduction pipe 76 and a gas discharge pipe 78 that penetrate through 74 b and are connected to the fuel cell stack 72 are provided. The gas introduction part 76 a inside the gas introduction pipe 76 communicates with a gas supply manifold 80 formed so as to penetrate in the stacking direction of the fuel cell stack 72, and the gas discharge part 78 a inside the gas discharge pipe 78 is connected to the fuel cell stack 72. The gas discharge manifold 82 is formed so as to penetrate in the stacking direction.

  When the anode gas supplied to the anode electrode side of the fuel cell 70 is hydrogen gas and the cathode gas supplied to the cathode electrode side is oxygen gas, when the fuel cell 70 generates power, it is converted to hydrogen ions and electrons on the anode electrode side. The hydrogen ions pass through the electrolyte membrane of the fuel cell 70, and the electrons reach the cathode side through an external circuit. On the cathode side, a reaction in which hydrogen ions, electrons, and oxygen gas react to generate moisture is performed.

  The anode gas and cathode gas supplied to the fuel cell 70 are humidified by a humidifier provided in the fuel cell system in order to impart ion conductivity to the electrolyte membrane of the fuel cell 70. However, since the temperatures of the anode gas and the cathode gas supplied to the fuel cell stack 72 are lower than the temperature of the fuel cell stack 72 during power generation, the temperature of the gas introduction part 76a in the end plates 74a and 74b decreases. . As a result, the anode gas and the cathode gas passing through the gas introduction part 76a in the end plates 74a and 74b may condense, and condensed water may be generated. Further, when the end plates 74a and 74b supplied to the fuel cell stack 72 are made of a metal plate or the like having a good thermal conductivity, the anode gas and the cathode gas are supplied from the gas introduction portions 76a in the end plate, When it passes through the gas discharge part 78a, it may condense by the influence of heat radiation and condensed water may be generated. In particular, the condensed water generated in the gas introduction part 76a in the end plates 74a and 74b easily flows into the fuel cell stack 72 by the anode gas or the cathode gas flowing through the gas introduction part 76a.

  When the condensed water generated in the gas introduction part (or gas discharge part) flows into the fuel cell stack 72, the supply of the anode gas or the cathode gas is hindered, and the power generation performance such as a voltage drop may be reduced.

  For example, Patent Document 1 proposes a fuel cell in which at least one of a gas supply manifold and a gas discharge manifold is inclined so as to become lower in the reaction gas traveling direction.

  Further, for example, in Patent Document 2, a gas supply manifold formed so as to penetrate from one end plate in the stacking direction of the unit cells and a gas supply manifold penetrating from the other end plate to the gas supply manifold are accumulated in the gas supply manifold. There has been proposed a fuel cell having a drainage channel for discharging the condensed water to the outside and inclining the bottom surface of the gas supply manifold toward the drainage channel.

  Further, for example, Patent Document 3 proposes a fuel cell in which an end plate is provided with a water reservoir portion that temporarily stores water and an inclined portion that is inclined downward from the manifold toward the water reservoir portion.

JP 2004-146303 A JP 2007-141039 A JP 2003-177871 A

  However, in the fuel cells of Patent Documents 1 and 2, the drainage of the condensed water generated in the manifold of the fuel cell stack is improved, and the condensed water generated in the gas introduction part supplied to the fuel cell stack is It is difficult to suppress the flow into the fuel cell.

  In addition, in the fuel cell of Patent Document 3, the configuration of the fuel cell is complicated because the water reservoir and the inclined portion that inclines toward the water reservoir are formed in the end plate.

  Therefore, an object of the present invention is to provide a fuel cell system that can suppress at least the condensed water generated in the gas introduction part from flowing into the fuel cell with a simple configuration.

  The present invention provides a fuel cell stack in which at least one fuel cell is stacked, an end plate provided at both ends of the fuel cell stack in the stacking direction, and the stack of the fuel cell stack through the end plate. A gas introduction portion that communicates with a gas supply manifold that is formed to penetrate in a direction, and a gas discharge portion that passes through the end plate and communicates with a gas discharge manifold that is formed so as to penetrate in the stacking direction of the fuel cell stack. The gas introduction part in the end plate is inclined so as to descend from the side facing the gas supply manifold toward the upstream side of the reaction gas passing through the gas introduction part.

  In the fuel cell system, the bottom surface of the gas supply manifold is perpendicular to the bottom surface of the gas introduction portion in the end plate at the boundary between the bottom surface of the gas introduction portion in the end plate and the bottom surface of the gas supply manifold. It is preferable that a step that is upward in the direction is formed.

  In the fuel cell system, the upper surface of the gas supply manifold is perpendicular to the upper surface of the gas introduction part in the end plate at the boundary between the upper surface of the gas introduction part in the end plate and the upper surface of the gas supply manifold. It is preferable that a step which is downward in the direction is formed.

  In the fuel cell system, the gas discharge part in the end plate may be inclined so as to descend from the side facing the gas discharge manifold toward the downstream side of the reaction gas passing through the gas discharge part. preferable.

  In the fuel cell system, the bottom surface of the gas discharge manifold is perpendicular to the bottom surface of the gas discharge portion in the end plate at the boundary between the bottom surface of the gas discharge portion in the end plate and the bottom surface of the gas discharge manifold. It is preferable that a step that is upward in the direction is formed.

  In the fuel cell system, the upper surface of the gas discharge manifold is perpendicular to the upper surface of the gas discharge portion in the end plate at the boundary between the upper surface of the gas discharge portion in the end plate and the upper surface of the gas discharge manifold. It is preferable that a step which is downward in the direction is formed.

According to the present invention, an end plate provided at both ends of the fuel cell stack in the stacking direction, a gas introduction portion that passes through the end plate and communicates with a gas supply manifold that is formed to penetrate in the stacking direction of the fuel cell stack, A gas discharge portion that communicates with a gas discharge manifold that is formed through the fuel cell stack in the stacking direction, and the gas introduction portion in the end plate is introduced from the side facing the gas supply manifold. The bottom surface of the gas supply manifold is inclined at the boundary between the bottom surface of the gas introduction portion in the end plate and the bottom surface of the gas supply manifold. A step is formed vertically above the bottom surface of the introduction portion, and the top surface of the gas introduction portion in the end plate and the top surface of the gas supply manifold The boundary portion, the Rukoto to form a step in which the upper surface of the gas supply manifold is vertically below the upper surface of the gas inlet in the end plate, the condensed water generated by at least the gas inlet flows into the fuel cell Can be provided with a simple configuration.

  Embodiments of the present invention will be described below.

  FIG. 1 is a schematic side view showing an example of the configuration of a fuel cell system according to an embodiment of the present invention. FIG. 2 is a partial schematic perspective view of the fuel cell system according to the embodiment of the present invention. As shown in FIGS. 1 and 2, the fuel cell system 1 includes a fuel cell stack 12 in which a plurality of fuel cells 10 are stacked, and a metal plate 14 as an end plate provided at both ends in the stacking direction of the fuel cell stack 12. And the insulating plate 16, the cathode gas introduction pipe 18, the cathode gas discharge pipe 20, the anode gas introduction pipe 22, the anode gas discharge pipe 24, the humidifier (A) 26, and the humidifier B (not shown). And a fastening tool 28. The fuel cell stack 12 is formed by stacking 20 fuel cells 10, but the number of fuel cells 10 may be at least one.

  The end plate is not necessarily the metal plate 14 and the insulating plate 16, but may be a metal plate coated with insulation. The metal plate 14 is not particularly limited as long as it is a pressure plate. For example, an aluminum plate, a stainless steel plate, or the like is used, and the insulating plate 16 is, for example, a resin plate such as phenol resin or polyphenylene sulfide. However, it is not limited to the above.

  The fastening tool 28 includes a fastening bolt 30 and a fixing base 32. When the fuel cell stack 12 is installed on the fixing base 32 and the tightening bolts 30 are tightened, a predetermined tightening pressure is applied to the fuel cell stack 12, and each fuel cell 10 is fixed.

  The humidifier (A) 26 is connected to the cathode gas introduction pipe 18 and the cathode gas discharge pipe 20, and the humidifier B (not shown) is connected to the anode gas introduction pipe 22 and the anode gas discharge pipe 24.

  As long as the humidifier used in the present embodiment humidifies the anode gas and cathode gas supplied to the fuel cell stack 12, a heating method, an ultrasonic method, a vaporization method, a bubbler method, a water vapor exchange method, etc. Various schemes can be employed. In the present embodiment, moisture contained in the wet gas (reaction gas discharged from the fuel cell stack 12) is absorbed by the water vapor exchange membrane, and moisture is supplied to the dry gas (reaction gas supplied to the fuel cell stack 12). As an example, a steam exchange type humidifier for supplying water will be described. The water vapor exchange membrane absorbs moisture from the wet gas and supplies moisture to the dry gas.

  3A and 3B are partial schematic cross-sectional views of the fuel cell system according to the embodiment of the present invention. As shown in FIGS. 3A and 3B, the fuel cell stack 12 includes a cathode gas supply manifold 34, a cathode gas discharge manifold 36, an anode gas supply manifold 38, and an anode gas discharge manifold which are formed to penetrate in the stacking direction. 40.

  As shown in FIGS. 3A and 3B, the cathode gas introduction pipe 18, the cathode gas discharge pipe 20, the anode gas introduction pipe 22 and the anode gas discharge pipe 24 are end plates (metal plate 14 and insulating plate 16). And is connected to the fuel cell stack 12.

  The cathode gas introduction part 18 a inside the cathode gas introduction pipe 18 communicates with the cathode gas supply manifold 34 of the fuel cell stack 12, and the cathode gas discharge part 20 a inside the cathode gas discharge pipe 20 communicates with the cathode gas discharge manifold 36. is doing. The anode gas introduction part 22 a inside the anode gas introduction pipe 22 communicates with the anode gas supply manifold 38, and the anode gas discharge part 24 a inside the anode gas discharge pipe 24 communicates with the anode gas discharge manifold 40.

  The configuration and the like of each introduction pipe and discharge pipe are not necessarily limited to the above. 4A and 4B are partial schematic cross-sectional views of a fuel cell system according to another embodiment of the present invention. As shown in FIGS. 4A and 4B, the cathode gas introduction pipe 18, the cathode gas discharge pipe 20, the anode gas introduction pipe 22 and the anode gas discharge pipe 24 are provided on the end plate (metal plate 14 and insulating plate 16). It is connected. In such a case, the cathode gas introduction portion 18a communicating with the cathode gas supply manifold 34, the cathode gas discharge portion 20a communicating with the cathode gas discharge manifold 36, the anode gas introduction portion 22a communicating with the anode gas supply manifold 38, and the anode gas discharge An anode gas discharge portion 24a communicating with the manifold 40 is formed directly on the end plate.

  The cathode gas introduction part 18 a formed on the end plate is a cathode gas introduction part 18 a of the cathode gas introduction pipe 18, and the cathode gas discharge part 20 a formed on the end plate is a cathode gas discharge part 20 a of the cathode gas discharge pipe 20. The anode gas introduction part 22a formed in the end plate is an anode gas introduction part 22a of the anode gas introduction pipe 22, and the anode gas discharge part 24a formed in the end plate is an anode gas discharge of the anode gas discharge pipe 24. It communicates with the part 24a.

5, as a reference example, which is a part schematic cross-sectional view of a fuel cell system in the dotted frame R in FIG. 3 (b). As shown in FIG. 5, the cathode gas introduction part 18a in the end plate (metal plate 14 and insulating plate 16) is formed from the side facing the cathode gas supply manifold 34 (dotted line A shown in FIG. 5). It inclines so that it may go down toward the upstream of the cathode gas which passes (arrow B shown in FIG. 4). The inclination of the cathode gas introduction part 18a in the end plate is such that the upper and lower surfaces (and the side faces) of the cathode gas introduction part 18a are lowered from the side facing the cathode gas supply manifold 34 toward the upstream side of the cathode gas. Means that The same applies to the anode gas introduction part 22a in the end plate.

In this reference example , at least one of the cathode gas introduction part 18a and the anode gas introduction part 22a in the end plate descends from the side facing the gas supply manifold toward the upstream side of the reaction gas passing through the gas introduction part. So long as it is inclined. However, when air is used as the cathode gas, air is supplied to the fuel cell stack 12 more than the anode gas (for example, hydrogen) in terms of reaction efficiency. Therefore, the flow velocity of the cathode gas flowing through the cathode gas introduction portion 18a is faster than the flow velocity of the anode gas flowing through the anode gas introduction portion 22a. Therefore, when condensed water is generated in the cathode gas introduction portion 18a, it is flowed into the cathode gas having a high flow rate and easily flows into the fuel cell stack 12. Therefore, it is preferable that the cathode gas introduction part 18a in the end plate is inclined so as to descend from the side facing the gas supply manifold toward the upstream side of the reaction gas passing through the gas introduction part.

6, as a reference example, which is a part schematic cross-sectional view showing another example of a fuel cell system in the dotted frame R in FIG. 3 (b). If the cathode gas introduction part 18a in the end plate is inclined so as to descend from the side facing the cathode gas supply manifold 34 toward the upstream side of the cathode gas passing through the cathode gas introduction part 18a, as shown in FIG. In addition, for example, a part of the cathode gas introduction part 18a in the end plate may have a flat part. The same applies to the anode gas introduction part 22a in the end plate.

  Even if condensed water is generated in the gas introduction part in the end plate by the influence of heat dissipation or the like when the reaction gas passes through the gas introduction part in the end plate by the above-described configuration, the fuel cell stack Inflow into the body 12 can be suppressed.

  Further, the inclination of the cathode gas introducing portion 18a can be formed by grinding, a mold or the like. 5 and 6, the external shape of the cathode gas introduction pipe 18 in the end plate (the cathode gas discharge pipe 20, the anode gas introduction pipe 22 and the anode gas discharge pipe 24 in the end plate are the same) is as follows. In order to facilitate positioning when connecting to the fuel cell stack 12, it is preferable that a step is formed so that the width becomes narrower from the end of the end plate toward the fuel cell stack 12. . The same applies to the anode gas introduction pipe 22, the cathode gas discharge pipe 20, and the anode gas discharge pipe 24. Such a step is formed by grinding, a mold or the like. Similarly, the end plate into which the gas introduction pipe and the gas discharge pipe are inserted is stepped by grinding, a mold or the like.

In this reference example , if the gas introduction part in the end plate is inclined as described above, the gas introduction part other than the end plate is not necessarily inclined, but the condensed water droplets fall. Preferably, it is formed vertically downward.

  FIG. 7 is a partial schematic cross-sectional view showing another example of the fuel cell system in the dotted line frame R of FIG. As shown in FIG. 7, the cathode gas supply manifold bottom surface 34a is perpendicular to the cathode gas introduction bottom surface 18b in the end plate at the boundary between the cathode gas introduction bottom surface 18b and the cathode gas supply manifold bottom surface 34a in the end plate. It is preferable that an upper step 42a is formed. Further, as shown in FIG. 7, the cathode gas supply manifold upper surface 34b is located at the boundary between the cathode gas introduction portion upper surface 18c and the cathode gas supply manifold upper surface 34b in the end plate than the cathode gas introduction portion upper surface 18c in the end plate. It is preferable that a step 42b that is vertically downward is formed. As shown in FIG. 7, it is preferable that both the steps 42a and 42b are formed, but at least one of them may be formed. The level difference serves as a barrier for preventing the condensed water generated in the gas introduction part in the end plate from flowing into the gas supply manifold.

  In the present embodiment, the cathode gas introduction portion 18a in the end plate has been described. However, the anode gas introduction portion 22a in the end plate shown in FIG. 3B is also described in the inclination described in FIGS. It is preferable to have a step. Further, the inclination angle and step width of the gas introduction part in the end plate in the present embodiment are not particularly limited.

  FIG. 8 is a schematic cross-sectional view showing an example of the configuration of the fuel battery cell used in the present embodiment. As shown in FIG. 8, the fuel cell 10 used in the present embodiment includes a membrane-electrode assembly 44, and an anode electrode separator 46 as a pair of fuel cell separators disposed via the membrane-electrode assembly 44. A cathode separator 48. The membrane-electrode assembly 44 includes an electrolyte membrane 50, and an anode 52 and a cathode 54 that sandwich the electrolyte membrane 50. In addition, an adhesive 56 for bonding the fuel cell separators is provided between the anode separator 46 and the cathode separator 48.

  FIG. 9A is a schematic plan view showing an example of the configuration of the anode separator used in this embodiment, and FIG. 9B shows an example of the configuration of the cathode separator used in this embodiment. It is a schematic plan view.

  As shown in FIGS. 9 (a) and 9 (b), the anode separator 46 and the cathode separator 48 are respectively an anode gas passage 58 or a cathode gas passage 60 as a reaction gas passage, and a cathode gas supply manifold hole 62. A cathode gas discharge manifold hole 64, an anode gas supply manifold hole 66, and an anode gas discharge manifold hole 68.

  When the fuel cells 10 are stacked, the cathode gas supply manifold holes 62 of the adjacent anode electrode separator 46 and cathode electrode separator 48 are overlapped, and the cathode gas discharge manifold hole 64 is overlapped, so that FIG. The cathode gas supply manifold 34 and the cathode gas discharge manifold 36 that are communicated in the stacking direction are formed as shown in FIG. Similarly, by overlapping the anode gas supply manifold hole 66 and overlapping the anode gas discharge manifold hole 68, the anode gas supply manifold 38 and the anode gas communicated in the stacking direction as shown in FIG. Each discharge manifold 40 is formed.

  Next, the flow of the reaction gas in the fuel cell system will be described. The anode gas humidified by the humidifier B (not shown) passes through the anode gas introduction part 22a shown in FIG. 3 (b), and passes through the end plate (metal plate 14 and insulating plate 16) to the anode of the fuel cell stack 12. It is introduced into the gas supply manifold 38 and supplied to each fuel cell 10. The anode gas supplied to the fuel cell 10 passes through the anode gas passage 58 via the anode gas supply manifold hole 66 shown in FIG. The anode gas that has not been used for power generation passes through the anode gas discharge manifold hole 68 and the anode gas discharge manifold 24a shown in FIG. To the humidifier B.

  Similarly, the cathode gas humidified by the humidifier (A) 26 shown in FIG. 1 passes through the cathode gas introduction part 18a shown in FIG. It is introduced into the cathode gas supply manifold 34 and supplied to each fuel cell 10. The cathode gas supplied to the fuel cell 10 passes through the cathode gas flow path 60 via the cathode gas supply manifold hole 62 shown in FIG. 9B, and is used for power generation of the fuel cell 10. The cathode gas not used for power generation passes from the cathode gas passage 60 through the cathode gas discharge manifold hole 64 to the cathode gas discharge manifold 36 and the cathode gas discharge portion 20a shown in FIG. (A) Introduced in 26.

  An example of the humidification method of the anode gas and the cathode gas by the humidifier (A) 26 and the humidifier B will be described. Cathode gas (wet gas) containing moisture discharged from the fuel cell stack is introduced into the humidifier (A) 26. The wet gas introduced into the humidifier (A) 26 comes into contact with one surface of the water vapor exchange membrane in the humidifier A (26), and moisture in the wet gas is absorbed and stored in the water vapor exchange membrane. On the other hand, the cathode gas (dry gas) supplied to the fuel cell stack is introduced into the humidifier (A) 26. When the dry gas introduced into the humidifier (A) 26 comes into contact with the other surface of the water vapor exchange membrane, the water stored in the water vapor exchange membrane is supplied to the dry gas and humidified. The humidification of the anode gas is performed by the humidifier B in the same manner as described above.

  FIGS. 10A and 10B are partial schematic cross-sectional views of a fuel cell system according to another embodiment of the present invention. As shown in FIGS. 10A and 10B, the cathode gas discharge part 20a and the anode in the end plate can be effectively suppressed from flowing in the condensed water into the fuel cell stack 12. It is preferable that at least one of the gas discharge portions 24a is inclined so as to descend from the side facing the gas discharge manifold toward the downstream side of the reaction gas passing through the gas discharge portion.

  FIG. 11 is a partial schematic cross-sectional view showing another example of the fuel cell system in the dotted line frame R of FIG. As shown in FIG. 11, the cathode gas discharge part 20a (the same applies to the anode gas discharge part 24a) is also provided on the boundary between the cathode gas discharge part bottom face 20b and the cathode gas discharge manifold bottom face 36a in the end plate. Preferably, a step 42a is formed so that 36a is vertically above the bottom surface 20b of the cathode gas discharge portion in the end plate. As shown in FIG. 11, the cathode gas discharge manifold upper surface 36b is located at the boundary between the cathode gas discharge portion upper surface 20c and the cathode gas discharge manifold upper surface 36b in the end plate than the cathode gas discharge portion upper surface 20c in the end plate. It is preferable that a step 42b that is vertically downward is formed. As shown in FIG. 11, it is preferable that both the steps 42a and 42b are formed, but at least one of them may be formed.

  Other configurations of the fuel cell system will be described. The fuel cell separator (anode electrode separator 46 and cathode electrode separator 48) used in the present embodiment is not particularly limited, such as a metal separator or a carbon separator.

  The electrolyte membrane 50 constituting the membrane-electrode assembly 44 used in the present embodiment is not particularly limited as long as it does not have electron transfer properties but has proton conductivity. For example, a perfluorosulfonic acid resin film, a copolymer film of a trifluorostyrene derivative, a polybenzimidazole film impregnated with phosphoric acid, an aromatic polyether ketone sulfonic acid film, and the like can be given.

  Each of the anode 52 and the cathode 54 constituting the membrane-electrode assembly 44 includes a catalyst layer and a diffusion layer.

  The diffusion layer is not particularly limited as long as it is a material having a high reaction gas diffusibility. Examples thereof include porous carbon materials such as carbon cloth and carbon paper.

  The catalyst layer is, for example, formed by mixing carbon carrying a metal catalyst such as platinum or ruthenium with a perfluorosulfonic acid-based electrolyte or the like on a diffusion layer or an electrolyte membrane. Examples of the carbon include carbon black such as acetylene black, furnace black, channel black, and thermal black.

  Thus, the fuel cell system according to the present embodiment is inclined such that the gas introduction part in the end plate is lowered from the side facing the gas supply manifold toward the upstream side of the reaction gas passing through the gas introduction part. Therefore, at least the condensed water generated in the gas introduction part can be prevented from flowing into the fuel cell with a simple configuration.

  The fuel cell and the fuel cell laminate according to the present embodiment can be used as, for example, a small power source for mobile devices such as a mobile phone and a portable personal computer, a power source for automobiles, and a household power source.

1 is a schematic side view illustrating an example of a configuration of a fuel cell system according to an embodiment of the present invention. 1 is a partial schematic perspective view of a fuel cell system according to an embodiment of the present invention. 1 is a partial schematic cross-sectional view of a fuel cell system according to an embodiment of the present invention. It is a partial schematic cross section of the fuel cell system concerning other embodiments of the present invention. As a reference example, it is a partial schematic cross-sectional view of the fuel cell system in a dotted frame R in FIG. As a reference example, it is a partial schematic cross-sectional view showing another example of a fuel cell system in a dotted frame R in FIG. It is a partial schematic cross section which shows another example of the fuel cell system in the dotted-line frame R of Fig.3 (a). It is a schematic cross section which shows an example of a structure of the fuel battery cell used by this embodiment. It is a schematic plan view which shows an example of a structure of the separator for fuel cells used for this embodiment. It is a partial schematic cross section of the fuel cell system concerning other embodiments of the present invention. FIG. 11 is a partial schematic cross-sectional view showing another example of the fuel cell system in a dotted frame R in FIG. 1 is a partial schematic cross-sectional view showing a configuration of a general fuel cell system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Fuel cell system 10,70 Fuel cell, 12,72 Fuel cell laminated body, 14 Metal plate, 16 Insulation plate, 18 Cathode gas introduction pipe, 18a Cathode gas introduction part, 18b Cathode gas introduction part bottom face, 18c Cathode gas Introduction part upper surface, 20 cathode gas discharge pipe, 20a cathode gas discharge part, 20b cathode gas discharge part bottom face, 20c cathode gas discharge part top face, 22 anode gas introduction pipe, 22a anode gas introduction part, 24 anode gas discharge pipe, 24a anode Gas exhaust, 28 Clamp, 30 Volt, 32 Fixing base, 34 Cathode gas supply manifold, 34a Cathode gas supply manifold bottom surface, 34b Cathode gas supply manifold top surface, 36 Cathode gas exhaust manifold, 36a Cathode gas exhaust manifold Bottom surface, 36b top surface of cathode gas discharge manifold, 38 anode gas supply manifold, 40 anode gas discharge manifold, 42a, 42b step, 44 membrane-electrode assembly, 46 anode electrode separator, 48 cathode electrode separator, 50 electrolyte membrane, 52 anode electrode , 54 Cathode electrode, 56 Adhesive, 58 Anode gas flow path, 60 Cathode gas flow path, 62 Cathode gas supply manifold hole, 64 Cathode gas discharge manifold hole, 66 Anode gas supply manifold hole, 68 Anode gas discharge manifold hole, 74a 74b End plate, 76 gas introduction pipe, 76a gas introduction section, 78 gas exhaust pipe, 78a gas exhaust section, 80 gas supply manifold, 82 gas exhaust manifold.

Claims (4)

A fuel cell stack in which a plurality of fuel battery cells are stacked, end plates provided at both ends in the stacking direction of the fuel cell stack, and through the end plates, the fuel cell stack is formed to penetrate in the stacking direction of the fuel cell stack A gas introduction part that communicates with the gas supply manifold, and a gas discharge part that passes through the end plate and communicates with a gas discharge manifold that is formed through the fuel cell stack in the stacking direction;
The gas introduction part in the end plate is inclined so as to descend from the side facing the gas supply manifold toward the upstream side of the reaction gas passing through the gas introduction part,
A step is formed at the boundary between the bottom surface of the gas introduction portion in the end plate and the bottom surface of the gas supply manifold so that the bottom surface of the gas supply manifold is vertically above the bottom surface of the gas introduction portion in the end plate. ,
A step is formed at the boundary between the upper surface of the gas introduction portion in the end plate and the upper surface of the gas supply manifold so that the upper surface of the gas supply manifold is vertically lower than the upper surface of the gas introduction portion in the end plate. ,
The stacking direction of the fuel cell stack is a direction parallel to a mounting surface on which the fuel cell stack is mounted, and the vertical direction is a direction perpendicular to the mounting surface. A fuel cell system.   2. The fuel cell system according to claim 1, wherein the gas discharge portion in the end plate is inclined so as to descend from the side facing the gas discharge manifold toward the downstream side of the reaction gas passing through the gas discharge portion. A fuel cell system characterized by comprising: 3. The fuel cell system according to claim 2, wherein a bottom surface of the gas discharge manifold in the end plate is located at a boundary portion between a bottom surface of the gas discharge portion in the end plate and a bottom surface of the gas discharge manifold. fuel cell system, characterized in that a step serving as the vertical above the bottom of are formed. 4. The fuel cell system according to claim 2, wherein an upper surface of the gas discharge manifold is located at a boundary portion between an upper surface of the gas discharge portion in the end plate and an upper surface of the gas discharge manifold. fuel cell system, wherein a level difference from the upper surface of the discharge section becomes the vertical downward is formed.