JP4613030B2 - Fuel cell stack - Google Patents

Description

  The present invention relates to a fuel cell stack in which a plurality of electrolyte / electrode assemblies each having electrodes provided on both sides of an electrolyte are stacked via a separator.

  For example, a solid polymer fuel cell employs a solid polymer electrolyte membrane made of a polymer ion exchange membrane. In this fuel cell, an electrolyte membrane / electrode structure in which an anode side electrode and a cathode side electrode each made of an electrode catalyst and porous carbon are provided on both sides of a solid polymer electrolyte membrane is sandwiched between separators (bipolar plates). It is composed of a single cell. Usually, a fuel cell stack using a laminate in which a predetermined number of single cells are laminated is used.

  In this type of fuel cell, a fuel gas, for example, a gas mainly containing hydrogen (hereinafter also referred to as a hydrogen-containing gas) is supplied to the anode side electrode, while an oxidant gas is supplied to the cathode side electrode. For example, oxygen-containing gas or air (hereinafter also referred to as oxygen-containing gas) is supplied. In the fuel gas supplied to the anode side electrode, hydrogen is ionized on the electrode catalyst and moves to the cathode side 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.

  The fuel cell stack is generally formed by penetrating the fuel cell stack in the stacking direction in order to supply an oxidant gas and a fuel gas, which are reaction gases, to the cathode side electrode and the anode side electrode. Stacking direction of the fuel cell stack in order to exhaust the oxidant gas and the fuel gas from the cathode side electrode and the anode side electrode, and the side communication hole and the fuel gas supply side communication hole (reaction gas supply side communication hole) And an oxidant gas discharge side communication hole and a fuel gas discharge side communication hole (reactive gas discharge side communication hole) formed therethrough.

  By the way, in particular, the generated water generated by the reaction on the electrode power generation surface is easily introduced into the oxidant gas discharge side communication hole, and the accumulated water is often present in the oxidant gas discharge side communication hole. In addition, in the fuel gas discharge side communication hole, there is a possibility that stagnant water is generated due to reverse diffusion or dew condensation of generated water through the electrolyte membrane. As a result, the oxidant gas discharge side communication hole and the fuel gas discharge side communication hole are reduced or blocked by the staying water, and the flow of the oxidant gas and the fuel gas is hindered, resulting in a problem that the power generation performance is lowered. .

  Thus, for example, a fuel cell stack disclosed in Patent Document 1 is known. In this fuel cell stack, an electrolyte / electrode assembly in which electrodes are provided on both sides of the electrolyte is provided with a laminate in which a plurality of layers are laminated via separators. This laminated body has a reaction gas supply side communication hole formed so as to penetrate in the laminating direction in order to supply the reaction gas to the corresponding electrode, and penetrates in the laminating direction in order to discharge the reaction gas from the corresponding electrode. The reaction gas discharge side communication hole is formed. Terminal terminals, insulators, and end plates are sequentially disposed at both ends in the stacking direction of the stack, respectively.

  The insulator or the end plate is provided with a bypass flow path connecting the reaction gas supply side communication hole and the reaction gas discharge side communication hole, and before the reaction gas is introduced into the laminate, The water is discharged from the bypass flow path to the reaction gas discharge side communication hole.

  For this reason, it is possible to reliably prevent the electrode power generation surface from being covered with water droplets with a simple and compact configuration, and to effectively maintain the power generation performance of the fuel cell stack. Yes.

Japanese Patent Laid-Open No. 2003-346869 (FIG. 5)

  An object of the present invention is to provide a fuel cell stack in which this type of bypass flow path is provided, and in particular, drainage can be further improved.

  The present invention comprises a laminate in which a plurality of electrolyte / electrode assemblies each provided with electrodes on both sides of an electrolyte are laminated with a separator interposed therebetween, and the laminate supplies a reaction gas to the corresponding electrode. For this purpose, a reaction gas supply side communication hole formed penetrating in the stacking direction and a reaction gas discharge side communication hole formed penetrating in the stacking direction to discharge the reaction gas from the corresponding electrode The fuel cell stack is provided with a terminal terminal plate, an insulator, and an end plate sequentially disposed at both ends in the stacking direction of the stack.

The insulator or the end plate is provided with one bypass flow path that connects the reaction gas supply side communication hole and the reaction gas discharge side communication hole, and the bypass flow path is connected to the reaction gas supply side communication hole. An opening cross-sectional area of the inlet opening is configured to be larger than an opening cross-sectional area of the outlet opening to the reaction gas discharge side communication hole, and the planar shape of the bypass flow path is the opening section from the inlet toward the outlet. area constitutes a wedge passage continuously decreases.

  Furthermore, it is preferable that the reaction gas supply side communication hole is disposed above the reaction gas discharge side communication hole. For this reason, water can flow smoothly in the bypass channel from the reaction gas supply side communication hole toward the reaction gas discharge side communication hole by its own weight.

  According to the present invention, since the inlet-side opening cross-sectional area of the bypass channel is set larger than the outlet-side opening cross-sectional area, the force for pushing water into the bypass channel is increased. As a result, the drainage of the reaction gas supply side communication hole is improved satisfactorily, the electrode power generation surface can be reliably prevented from being covered with water droplets with a simple and compact configuration, and the power generation performance of the fuel cell stack can be improved. It becomes possible to maintain it effectively.

  FIG. 1 is a schematic overall perspective view of a fuel cell stack 10 according to a first embodiment of the present invention, and FIG. 2 is a partial sectional side view of the fuel cell stack 10.

  The fuel cell stack 10 includes a stacked body 14 in which a plurality of single cells 12 are stacked in a horizontal direction (arrow A direction), and negative terminal terminals are provided at both ends of the stacked body 14 in the stacking direction (arrow A direction), respectively. The plate 16a, the positive terminal terminal plate 16b, the insulator portions 18a and 18b, and the end plates 20a and 20b are sequentially arranged outward.

  As shown in FIGS. 2 and 3, each single cell 12 includes an electrolyte membrane / electrode structure (electrolyte / electrode assembly) 24, and first and second separators 26 that sandwich the electrolyte membrane / electrode structure 24. , 28. The first and second separators 26 and 28 are made of, for example, a metal plate, and a resin seal member having an insulating and sealing function is integrally formed. In addition, you may comprise the 1st and 2nd separators 26 and 28 with a carbon member.

  An oxidant gas supply for supplying an oxidant gas, for example, an oxygen-containing gas, to one end edge of the long side (in the direction of arrow B in FIG. 3) of the unit cell 12 in communication with the arrow A direction. Side communication hole (reaction gas supply side communication hole) 30a, cooling medium supply side communication hole 32a for supplying a cooling medium, and fuel gas discharge side communication hole (reaction for discharging a hydrogen-containing gas, for example) Gas exhaust side communication hole) 34b is provided.

  The other end edge of the long side of the single cell 12 communicates with each other in the direction of arrow A, a fuel gas supply side communication hole (reaction gas supply side communication hole) 34a for supplying fuel gas, and a cooling medium. A cooling medium discharge side communication hole 32b for discharging and an oxidant gas discharge side communication hole (reactive gas discharge side communication hole) 30b for discharging oxidant gas are provided.

  The electrolyte membrane / electrode structure 24 includes, for example, a solid polymer electrolyte membrane 36 in which a perfluorosulfonic acid thin film is impregnated with water, and an anode side electrode 38 and a cathode side electrode 40 that sandwich the solid polymer electrolyte membrane 36. With.

  The anode side electrode 38 and the cathode side electrode 40 are composed of a gas diffusion layer made of carbon paper or the like, and an electrode catalyst layer in which porous carbon particles having a platinum alloy supported on the surface are uniformly applied to the surface of the gas diffusion layer. Respectively. The electrode catalyst layer is bonded to both surfaces of the solid polymer electrolyte membrane 36.

  As shown in FIGS. 3 and 4, the fuel gas that communicates the fuel gas supply side communication hole 34 a and the fuel gas discharge side communication hole 34 b to the surface 26 a of the first separator 26 facing the electrolyte membrane / electrode structure 24. A flow path 42 is formed. The fuel gas channel 42 includes, for example, a plurality of grooves extending in the arrow B direction. As shown in FIG. 3, a cooling medium flow path 44 that connects the cooling medium supply side communication hole 32 a and the cooling medium discharge side communication hole 32 b is formed on the surface 26 b of the first separator 26. The cooling medium flow path 44 includes a plurality of grooves extending in the direction of arrow B.

  On the surface 28a of the second separator 28 facing the electrolyte membrane / electrode structure 24, for example, an oxidant gas flow path 46 composed of a plurality of grooves extending in the direction of arrow B is provided. The passage 46 communicates with the oxidant gas supply side communication hole 30a and the oxidant gas discharge side communication hole 30b.

  As shown in FIG. 5, the insulator portion 18 a disposed outside the negative terminal terminal plate 16 a is formed by laminating a first insulating plate 50, an intermediate insulating plate 52 and a second insulating plate 54 in the direction of arrow A. Composed. On the surface 50a of the first insulating plate 50 facing the intermediate insulating plate 52, as shown in FIGS. 5 and 6, a bypass flow connecting the oxidant gas supply side communication hole 30a and the oxidant gas discharge side communication hole 30b. A path 56 is formed.

  The bypass passage 56 is configured such that the opening cross-sectional area on the inlet 56a side is larger than the opening cross-sectional area on the outlet 56b side. The bypass channel 56 actually constitutes a wedge-shaped channel whose opening cross-sectional area continuously decreases from the inlet 56a toward the outlet 56b.

  As shown in FIG. 5, a bypass flow path 58 that connects the fuel gas supply side communication hole 34 a and the fuel gas discharge side communication hole 34 b is formed on the surface 54 a of the second insulation plate 54 that faces the intermediate insulation plate 52. . The bypass flow path 58 has a larger opening cross-sectional area on the inlet 58 a side than an opening cross-sectional area on the outlet 58 b side, and is set in the same shape as the bypass flow path 56.

  The insulator portion 18b is configured in the same manner as the above-described insulator portion 18a. The same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 1, an oxidant gas supply side communication hole 30a, a coolant supply side communication hole 32a, and a fuel gas discharge side communication hole 34b are provided at one end edge of the end plate 20a on the long side (arrow B direction). Are provided with an oxidant gas supply port 60a, a coolant supply port 62a, and a fuel gas discharge port 64b. A fuel gas supply port 64a that communicates with the fuel gas supply side communication hole 34a, the cooling medium discharge side communication hole 32b, and the oxidant gas discharge side communication hole 30b is provided at the other end edge of the long side of the end plate 20a. A discharge port 62b and an oxidant gas discharge port 60b are provided.

  The operation of the fuel cell stack 10 according to the first embodiment configured as described above will be described below.

  As shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied from the oxidant gas supply port 60a of the end plate 20a into the fuel cell stack 10, and a hydrogen-containing gas or the like is supplied from the fuel gas supply port 64a. The fuel gas is supplied. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied from the cooling medium supply port 62a. For this reason, in the laminated body 14, oxidant gas, fuel gas, and a cooling medium are supplied in series to the arrow A1 direction with respect to the multiple unit cell 12 piled up in the arrow A direction.

  As shown in FIG. 3, the oxidant gas is introduced into the oxidant gas flow path 46 of the second separator 28 from the oxidant gas supply side communication hole 30 a, and the cathode side electrode 40 constituting the electrolyte membrane / electrode structure 24. Move along. On the other hand, the fuel gas is introduced into the fuel gas flow path 42 of the first separator 26 from the fuel gas supply side communication hole 34 a and moves along the anode side electrode 38 constituting the electrolyte membrane / electrode structure 24.

  Therefore, in each electrolyte membrane / electrode structure 24, the oxidant gas supplied to the cathode side electrode 40 and the fuel gas supplied to the anode side electrode 38 are consumed by an electrochemical reaction in the electrode catalyst layer, Power generation is performed.

  Next, the consumed oxidant gas supplied to the cathode side electrode 40 flows in the direction of the arrow A2 along the oxidant gas discharge side communication hole 30b, and is then discharged from the oxidant gas discharge port 60b of the end plate 20a. The Similarly, the fuel gas supplied and consumed to the anode side electrode 38 is discharged to the fuel gas discharge side communication hole 34b and flows in the direction of arrow A2, and then discharged from the fuel gas discharge port 64b of the end plate 20a. .

  The cooling medium supplied to the cooling medium supply port 62a is introduced into the cooling medium flow path 44 of the first separator 26 from the cooling medium supply side communication hole 32a, and then flows along the arrow B direction. The cooling medium cools the electrolyte membrane / electrode structure 24, then moves through the cooling medium discharge side communication hole 32b in the direction of arrow A2, and is discharged from the cooling medium discharge port 62b of the end plate 20a.

  By the way, when the fuel cell stack 10 is started or when power generation of the fuel cell stack 10 is temporarily stopped and then restarted, piping for supplying an oxidant gas or fuel gas to the fuel cell stack 10 is started. The temperature of (not shown) may decrease, and condensed water may be generated in the pipe.

  Here, in 1st Embodiment, the insulator part 18a is interposed between the negative electrode side terminal terminal board 16a and the end plate 20a corresponding to the entrance vicinity of the oxidizing gas supply side communication hole 30a. Therefore, when the oxidant gas supplied to the oxidant gas supply port 60a of the end plate 20a is introduced from the first insulation plate 50 to the intermediate insulation plate 52 as shown in FIG. Water (condensed water) moves to the bypass channel 56 formed on the surface 50 a of the plate 50. This moisture is sent from the bypass channel 56 to the oxidant gas discharge side communication hole 30b and then discharged from the oxidant gas discharge port 60b of the end plate 20a.

  At that time, force F is applied to the water introduced into the inlet 56a of the bypass channel 56 toward the outlet 56b. This force F is obtained from F = {(pressure on the inlet 56a side) × (area on which pressure acts) + gravity} − {(pressure on outlet 56b side) × (area on which pressure acts) + surface tension of water}. It is determined.

  Therefore, when the opening cross-sectional area on the inlet 56a side is configured to be larger than the opening cross-sectional area on the outlet 56b side, the force F for pushing water into the bypass channel 56 increases. For this reason, in the bypass flow path 56, water is favorably discharged toward the oxidant gas discharge side communication hole 30b, and the drainage of the oxidant gas supply side communication hole 30a is effectively improved.

  On the other hand, the fuel gas supplied to the fuel gas supply port 64 a of the end plate 20 a is introduced into the fuel gas supply side communication hole 34 a of the second insulating plate 54 through the first insulating plate 50 and the intermediate insulating plate 52. The moisture introduced into the fuel gas supply side communication hole 34 a moves to the bypass flow path 58 formed on the surface 54 a of the second insulating plate 54.

  In that case, the bypass flow path 58 is configured such that the opening cross-sectional area on the inlet 58a side is larger than the opening cross-sectional area on the outlet 58b side. Therefore, moisture is discharged from the bypass flow path 58 toward the fuel gas discharge side communication hole 34b and then discharged from the fuel gas discharge port 64b of the end plate 20a.

  As a result, in the first embodiment, it is possible to reliably prevent the dew condensation water from being introduced into the laminate 14 and the electrode power generation surface (electrode catalyst layer) from being covered with water droplets. It becomes possible to maintain performance effectively. Moreover, it is only necessary to interpose the insulator portion 18a between the negative terminal terminal plate 16a and the end plate 20a, and excess moisture can be reliably removed with a simple and compact configuration.

  Further, in the fuel cell stack 10, an insulator part 18b is interposed between the positive terminal terminal plate 16b and the end plate 20b. For this reason, the generated water which tends to stay in the back side (end plate 20b side) of the laminated body 14 is pushed out satisfactorily, and the discharge performance of the generated water and the condensed water is effectively improved.

FIG. 7 is a partial cross-sectional side view of a fuel cell stack 70 according to the second embodiment of the present invention. The same components as those of the fuel cell stack 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted .

  In the fuel cell stack 70, end plates 74a and 74b are laminated outside the negative electrode side terminal terminal plate 16a and the positive electrode side terminal terminal plate 16b via insulator plates 72a and 72b, and the end plate 74a, Lid plates 76a and 76b are attached to 74b.

  As shown in FIG. 8, a bypass channel 80 that connects the oxidant gas supply port 60a and the oxidant gas discharge port 60b is formed on the surface 78a of the end plate 74a facing the lid plate 76a. A bypass channel 82 that connects the fuel gas supply port 64a and the fuel gas discharge port 64b is formed on a surface 78b of the end plate 74a that faces the insulator plate 72a.

  The bypass flow path 80 is configured such that the opening cross-sectional area on the inlet 80a side is larger than the opening cross-sectional area on the outlet 80b side, and the bypass flow path 82 has an opening cross-sectional area on the outlet 82b side. It is configured to be larger than the area. The bypass channels 80 and 82 actually constitute a wedge-shaped channel whose opening cross-sectional area continuously decreases in the flow direction. The end plate 74b is configured in the same manner as the end plate 74a, and a detailed description thereof is omitted.

  In the second embodiment configured as described above, the end plates 74a and 74b constituting the fuel cell stack 70 are included in the fuel gas and the bypass channel 80 for removing moisture contained in the oxidant gas. A bypass channel 82 for removing moisture is provided. Moreover, the bypass channels 80 and 82 are configured such that the opening cross-sectional areas on the respective inlets 80a and 82a side are larger than the opening cross-sectional areas on the respective outlets 80b and 82b side.

  For this reason, the drainage from the bypass flow paths 80 and 82 is improved satisfactorily, and excess moisture can be reliably prevented from being introduced into the laminate 14. As a result, the same effects as those of the first embodiment can be obtained, for example, the power generation performance of the entire fuel cell stack 70 can be effectively maintained with a simple and compact configuration.

As shown in FIG. 9, in the insulator portion 84 related to the present invention, a bypass flow connecting the oxidant gas supply side communication hole 30 a and the oxidant gas discharge side communication hole 30 b to the surface 50 a of the first insulating plate 50. A path 88 is formed. The bypass channel 88 is configured such that the opening sectional area on the inlet 88a side is larger than the opening sectional area on the outlet 88b side. In practice, the bypass channel 88 has an opening cross-sectional area enlarged by the oxidant gas supply side communication hole 30a, and the remaining portion is set to have the same thickness (same opening cross-sectional area).

  A bypass channel 90 that connects the fuel gas supply side communication hole 34 a and the fuel gas discharge side communication hole 34 b is formed in the surface 54 a of the second insulating plate 54. The bypass flow path 90 is configured such that the opening cross-sectional area on the inlet 90a side is larger than the opening cross-sectional area on the outlet 90b side, and the opening cross-sectional area increases on the fuel gas supply side communication hole 34a side, while on the outlet 90b side. The thickness is set to be approximately the same.

As shown in FIG. 10, in the insulator portion 86 related to the present invention, a bypass channel 92 is formed in the first insulating plate 50 and a bypass channel 94 is formed in the second insulating plate 54. The bypass passages 92 and 94 are configured such that the opening cross-sectional area on the inlet 92a and 94a side is larger than the opening cross-sectional area on the outlet 92b and 94b side. The bypass channels 92 and 94 actually constitute a saw-toothed channel whose opening cross-sectional area decreases for a while from the inlets 92a and 94a toward the outlets 92b and 94b.

FIG. 11 is a schematic overall perspective view of a fuel cell stack 100 relating to the present invention.

  The end plate 20a constituting the fuel cell stack 100 includes an oxidant gas supply pipe (reactive gas introduction passage) 102a corresponding to the oxidant gas supply port 60a, the cooling medium supply port 62a, and the fuel gas discharge port 64b, respectively, The medium supply pipe 104a and the fuel gas discharge pipe (reactive gas outlet passage) 106b are connected. The end plate 20a further includes a fuel gas supply pipe (reaction gas introduction passage) 106a, a cooling medium discharge pipe 104b, and an oxidant corresponding to the fuel gas supply port 64a, the coolant discharge port 62b, and the oxidant gas discharge port 60b, respectively. A gas exhaust pipe (reactive gas outlet passage) 102b is attached.

  A bypass pipe 108 is connected to the oxidant gas supply pipe 102a and the oxidant gas discharge pipe 102b, and a bypass pipe 110 is similarly connected to the fuel gas supply pipe 106a and the fuel gas discharge pipe 106b. .

  As shown in FIG. 12, the oxidant gas supply pipe 102a and the fuel gas supply pipe 106a are provided with a ring-shaped wall plate portion 112, which is a baffle plate, protruding in the flow path of the oxidant gas and the fuel gas. The inlets 108a and 110a of the bypass pipes 108 and 110 are connected to a position separated from the wall plate 112 by a predetermined distance rearward in the flow direction (arrow A2 direction). The inlets 108a and 110a are widened, and the opening sectional areas of the inlets 108a and 110a are larger than the opening sectional areas of the outlets 108b and 110b of the bypass pipes 108 and 110, respectively.

  The wall plate 112 is not provided in the oxidant gas discharge pipe 102b and the fuel gas discharge pipe 106b. Solenoid valves 114a and 114b for opening and closing the respective pipelines are attached to the bypass pipes 108 and 110, respectively.

In this case , when the temperature is low, such as at the time of starting, or when the voltage is lowered, the conduits of the bypass pipes 108 and 110 are opened via the electromagnetic valves 114a and 114b. For this reason, for example, when the oxidant gas moves in the direction of the arrow A1 together with moisture (condensation water) in the oxidant gas supply pipe 102a, the moisture is caused by the wall plate portion 112 formed in the oxidant gas supply pipe 102a. To be supplemented.

  Therefore, the water is satisfactorily sent through the inlet 108a that expands to the bypass pipe 108 that communicates with the lower end side of the oxidant gas supply pipe 102a. Moisture is reliably discharged to the oxidant gas discharge pipe 102b through the bypass pipe 108, while only the oxidant gas that has been appropriately humidified is supplied into the fuel cell stack 100.

Thus, it is only providing the bypass pipe 108, 110 for connecting the external to the oxidant gas supply pipe 102a and the fuel gas supply pipe 106a of the fuel cell stack 100, an oxidant gas discharge pipe 102b and the fuel gas discharge pipe 106b The overall structure of the fuel cell stack 100 is effectively simplified. Moreover, since the bypass pipes 108 and 110 are attached to the outside of the fuel cell stack 100, there is an effect that assembly workability and maintenance management are further simplified.

1 is a schematic overall perspective view of a fuel cell stack according to a first embodiment of the present invention. It is a partial cross section side view of the said fuel cell stack. It is a disassembled perspective view of the single cell which comprises the said fuel cell stack. It is front explanatory drawing of one surface of the 1st separator which comprises the said single cell. It is a disassembled perspective explanatory drawing of the insulator part which comprises the said fuel cell stack. It is front explanatory drawing of one surface of the 1st insulating plate which comprises the said insulator part. It is a partial cross section side view of the fuel cell stack concerning the 2nd Embodiment of the present invention. It is a disassembled perspective view of the end plate which comprises the said fuel cell stack. It is a disassembled perspective explanatory drawing of the insulator part which comprises the fuel cell stack relevant to this invention. It is a disassembled perspective explanatory drawing of the insulator part which comprises the fuel cell stack relevant to this invention. 1 is a schematic overall perspective view of a fuel cell stack related to the present invention. It is a partial cross section explanatory view of the reaction gas supply pipe which constitutes the fuel cell stack.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 70, 100 ... Fuel cell stack 12 ... Single cell 14 ... Laminated body 16a, 16b ... Terminal terminal board 18a, 18b, 84, 86 ... Insulator part 20a, 20b, 74a, 74b ... End plate 24 ... Electrolyte membrane electrode Structures 26, 28 ... Separator 30a ... Oxidant gas supply side communication hole 30b ... Oxidant gas discharge side communication hole 32a ... Cooling medium supply side communication hole 32b ... Cooling medium discharge side communication hole 34a ... Fuel gas supply side communication hole 34b ... Fuel gas discharge side communication hole 36 ... Solid polymer electrolyte membrane 38 ... Anode side electrode 40 ... Cathode side electrode 42 ... Fuel gas flow path 44 ... Coolant flow path 46 ... Oxidant gas flow path 50, 54 ... Insulating plate 52 ... Intermediate insulating plates 56, 58, 80, 82, 88 to 94 ... Bypass channels 56a, 58a, 80a, 82a, 88a to 94 a, 108a, 110a ... Inlet 56b, 58b, 80b, 82b, 88b-94b, 108b, 110b ... Outlet 60a ... Oxidant gas supply port 60b ... Oxidant gas discharge port 62a ... Cooling medium supply port 62b ... Cooling medium discharge port 64a ... Fuel gas supply port 64b ... Fuel gas discharge ports 72a, 72b ... Insulator plates 76a, 76b ... Lid plate 102a ... Oxidant gas supply tube 102b ... Oxidant gas discharge tube 104a ... Cooling medium supply tube 104b ... Cooling medium discharge tube 106a ... Fuel gas supply pipe 106b ... Fuel gas discharge pipe 108, 110 ... Bypass pipe 112 ... Wall plate

Claims (2)

An electrolyte / electrode assembly provided with electrodes on both sides of an electrolyte includes a laminate in which a separator is interposed, and the laminate is provided in a stacking direction for supplying a reaction gas to the corresponding electrode. A reaction gas supply side communication hole formed so as to penetrate through the substrate, and a reaction gas discharge side communication hole formed so as to penetrate in the stacking direction in order to discharge the reaction gas from the corresponding electrode. A fuel cell stack in which a terminal terminal plate, an insulator, and an end plate are sequentially arranged outward at both ends in the stacking direction of the body,
The insulator or the end plate is provided with one bypass flow path connecting the reaction gas supply side communication hole and the reaction gas discharge side communication hole,
The bypass flow path is configured such that an opening cross-sectional area of an inlet opening in the reaction gas supply side communication hole is larger than an opening cross-sectional area of an outlet opening in the reaction gas discharge side communication hole,
The planar shape of the bypass passage, the fuel cell stack, characterized by configuring the wedge channel, wherein the opening cross-sectional area toward the outlet from the inlet is reduced continuously. The fuel cell stack according to claim 1 Symbol placement, the reaction gas supply communication hole, a fuel cell stack, characterized in that disposed above said reaction gas discharge passage.

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