JP5385033B2 - Fuel cell - Google Patents

Description

  The present invention includes a plurality of power generation units in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of an electrolyte and a separator are horizontally stacked, and an electrode facing surface of the separator is provided along the electrodes. The present invention relates to a fuel cell in which a reaction gas flow path for supplying a reaction gas that is a fuel gas or an oxidant gas is provided, and a reaction gas communication hole that passes through the reaction gas through the stacking direction is provided.

  For example, in a polymer electrolyte fuel cell, an electrolyte membrane / electrode structure (MEA) in which an anode side electrode and a cathode side electrode are disposed on both sides of an electrolyte membrane made of a polymer ion exchange membrane is provided by a pair of separators. The power generation unit is sandwiched. This type of fuel cell is normally used as a fuel cell stack by stacking a predetermined number of power generation units.

  In the above fuel cell, a fuel gas flow channel for flowing fuel gas is provided in the plane of one separator so as to face the anode side electrode, and the cathode side electrode is opposed in the plane of the other separator. An oxidant gas flow path for flowing an oxidant gas is provided. Further, between the separators adjacent to each other, a cooling medium flow path for flowing the cooling medium is provided along the surface direction of the separator.

  Further, in this type of fuel cell, a fuel gas inlet communication hole and a fuel gas outlet communication hole for flowing fuel gas through the power generation unit in the stacking direction, and an oxidant gas inlet communication hole for flowing oxidant gas In many cases, a so-called internal manifold type fuel cell is provided which includes an oxidant gas outlet communication hole, a cooling medium inlet communication hole for flowing a cooling medium, and a cooling medium outlet communication hole.

  As an internal manifold type fuel cell, for example, a polymer electrolyte fuel cell disclosed in Patent Document 1 is known. In this fuel cell, as shown in FIG. 12, a plurality of anode side flow paths 1 are formed along the vertical direction, and a water distribution board 2 and a gas distribution board are disposed upstream of the anode side flow path 1. 3 is disposed. The water distribution substrate 2 and the gas distribution substrate 3 are each formed with a plurality of pores 2 a and 3 a, and the pores 2 a and 3 a communicate with the anode side flow path 1.

  A pair of water introduction manifold holes 4a and 4a and fuel gas introduction manifold holes 5a and 5a are formed on both sides of the upper side of the fuel cell. A pair of manifold holes 5b and 5b for deriving fuel gas and manifold holes 4b and 4b for deriving water are formed on both sides of the lower side of the fuel cell.

  Water is supplied from a water pump 6 to the water introduction manifold holes 4a and 4a, while fuel gas is supplied from a hydrogen gas cylinder 7 to the fuel gas introduction manifold holes 5a and 5a. The water outlet manifold holes 4b and 4b and the fuel gas outlet manifold holes 5b and 5b communicate with the separation tank 8, and the water stored in the separation tank 8 is cooled by the cooler 9. The water is supplied to the manifold holes 4a and 4a through the water pump 6.

Japanese Patent No. 3123992

  In the above-mentioned Patent Document 1, water contained in the fuel gas used for the reaction through the anode side flow path 1 is led to the manifold holes 4b and 4b and sent to the separation tank 8, while this used Water contained in the fuel gas is introduced into the separation tank 8 and separated from the fuel gas.

  However, the downstream side (lower end portion side) of the anode-side channel 1 has a problem that water is particularly likely to stay and it is difficult to reliably discharge a large amount of the staying water.

  In addition, each of the fuel cells includes a pair of water introduction manifold holes 4a and 4a, a fuel gas introduction manifold hole 5a and 5a, a water discharge manifold hole 4b and 4b, and a fuel gas discharge manifold hole 5b, 5b is provided. For this reason, there is a problem that the configuration of the entire fuel cell is complicated, the fuel cell is increased in size, and the cost is increased.

  The present invention solves this type of problem, and an object thereof is to provide a fuel cell capable of easily and reliably discharging stagnant water from the separator surface with a simple and compact configuration.

  The present invention includes a plurality of power generation units in which an electrolyte / electrode structure in which a pair of electrodes are provided on both sides of an electrolyte and a separator are stacked, and a fuel gas or The present invention relates to a fuel cell in which a reaction gas flow path for supplying a reaction gas that is an oxidant gas is provided, and a reaction gas communication hole is provided that passes through the reaction gas in the stacking direction.

In this fuel cell, the lower end portion of the reaction gas flow path is provided with an outlet buffer portion communicating with the reaction gas communication hole on the outlet side, and drainage having an outlet protruding into the reaction gas communication hole on the outlet side. A reaction passage portion extending from the outlet buffer portion to the inside of the reaction gas communication hole on the outlet side, and retaining the water remaining in the outlet buffer portion from the outlet of the drain passage portion to the outlet side. A drainage passage portion is provided for discharging to the gas communication hole.

  Moreover, in this fuel cell, it is preferable that the outlet of the drainage passage portion has a drainage port that opens in a direction inclined with respect to the gas flow direction of the reaction gas communication hole on the outlet side.

  Furthermore, in this fuel cell, it is preferable that the electrolyte / electrode structure and the separator are stacked in the horizontal direction, and the inlet of the drainage passage is opened at the lowest position of the outlet buffer.

  Furthermore, in this fuel cell, it is preferable that the drain passage portions provided in the power generation units adjacent to each other are arranged in a staggered manner with respect to the stacking direction.

  In this fuel cell, the outlet of the drainage passage is preferably configured to narrow toward the outlet side reaction gas communication hole.

  Furthermore, in this fuel cell, it is preferable that the inlet of the drainage passage portion is configured to expand toward the outlet buffer portion.

  Furthermore, in this fuel cell, it is preferable that the drainage passage part is constituted by a pipe member that extends from the outlet buffer part to the inside of the reaction gas communication hole on the outlet side.

  Moreover, in this fuel cell, it is preferable that at least a portion of the pipe member that enters the reaction gas communication hole on the outlet side has an elliptical shape that is long in the flow direction of the reaction gas.

  Further, in this fuel cell, the separator is constituted by a metal plate, and the drainage passage portion is formed by overlapping the first bent portion of one of the separators adjacent to each other and the second bent portion of the other separator. It is preferable to be configured integrally.

  Furthermore, in this fuel cell, the first bent part on the upstream side in the reaction gas flow direction of the reaction gas communication hole on the outlet side may be set to a size larger than the second bent part on the downstream side in the reaction gas flow direction. preferable.

  According to the present invention, the drainage passage portion is provided so as to extend from the outlet buffer portion to the inside of the reaction gas communication hole on the outlet side. For this reason, the outlet of the drainage passage is opened inside the reaction gas communication hole where the flow of the reaction gas is fast, and a negative pressure is generated at the outlet of the drainage passage.

  Therefore, the retained water in the outlet buffer is good through the pushing force by the reactive gas flowing in the outlet buffer and the negative pressure generated at the outlet of the drainage passage by the flow rate of the reactive gas flowing through the reactive gas communication hole. To be discharged. Accordingly, it is possible to easily and reliably discharge the accumulated water from the separator surface with a simple and compact configuration, and the drainage performance can be improved.

It is a principal part disassembled perspective explanatory drawing of the electric power generation unit which comprises the fuel cell which concerns on the 1st Embodiment of this invention. FIG. 2 is a sectional view of the fuel cell taken along line II-II in FIG. 1. It is front explanatory drawing of the 2nd separator which comprises the said electric power generation unit. It is principal part expansion explanatory drawing of the pipe member which comprises the said fuel cell. It is an expansion perspective explanatory view of a pipe member which constitutes a fuel cell concerning a 2nd embodiment of the present invention. It is operation | movement explanatory drawing of the said pipe member. It is principal part expansion explanatory drawing of the pipe member which comprises the fuel cell which concerns on the 3rd Embodiment of this invention. It is principal part expansion explanatory drawing of the pipe member which comprises the fuel cell which concerns on the 4th Embodiment of this invention. It is a disassembled perspective explanatory drawing of the electric power generation unit which comprises the fuel cell which concerns on the 5th Embodiment of this invention. It is expansion explanatory drawing of the pipe member which comprises the said fuel cell. It is a disassembled perspective explanatory drawing of the electric power generation unit which comprises the fuel cell which concerns on the 6th Embodiment of this invention. 2 is an explanatory diagram of a polymer electrolyte fuel cell disclosed in Patent Document 1. FIG.

  As shown in FIG. 1, the fuel cell 10 according to the first embodiment of the present invention includes a power generation unit 12, and the plurality of power generation units 12 are stacked on each other along, for example, a horizontal direction (arrow A direction). To make up the stack. In addition, the electric power generation unit 12 may be laminated | stacked on the gravitational direction (vertical direction). At that time, the outlet of the pipe member described later is set downward (in the direction of gravity).

  As shown in FIGS. 1 and 2, the power generation unit 12 includes a first separator 14, an electrolyte membrane / electrode structure (electrolyte / electrode structure) 16, and a second separator 18. The first separator 14 and the second separator 18 are made of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a vertically long metal plate having a surface treated for anticorrosion on its metal surface.

  The first separator 14 and the second separator 18 have a rectangular planar shape, and are formed into a concavo-convex shape by pressing a metal thin plate into a wave shape. In addition, you may comprise the 1st separator 14 and the 2nd separator 18 with a carbon separator, for example.

  The electrolyte membrane / electrode structure 16 includes, for example, a solid polymer electrolyte membrane 22 in which a thin film of perfluorosulfonic acid is impregnated with water, and an anode side electrode 24 and a cathode side electrode 26 that sandwich the solid polymer electrolyte membrane 22. With. The anode side electrode 24 constitutes a so-called stepped MEA having a smaller surface area than the cathode side electrode 26.

  The anode side electrode 24 and the cathode side electrode 26 are uniformly coated on the surface of the gas diffusion layer with a gas diffusion layer (not shown) made of carbon paper or the like and porous carbon particles carrying a platinum alloy on the surface. And an electrode catalyst layer (not shown) formed. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 22.

  As shown in FIG. 1, the upper end edge of the power generation unit 12 in the long side direction (arrow C direction) communicates with each other in the direction of arrow A to oxidize for supplying an oxidant gas, for example, an oxygen-containing gas. An agent gas inlet communication hole (reaction gas communication hole) 30a and a fuel gas inlet communication hole (reaction gas communication hole) 32a for supplying a fuel gas, for example, a hydrogen-containing gas, are provided.

  A fuel gas outlet communication hole (reactive gas communication hole) 32b for communicating with each other in the direction of arrow A to discharge fuel gas is formed at the lower edge of the long side direction (arrow C direction) of the power generation unit 12, and oxidation An oxidant gas outlet communication hole (reaction gas communication hole) 30b for discharging the agent gas is provided.

  At one edge of the power generation unit 12 in the short side direction (arrow B direction), there is provided a cooling medium inlet communication hole 34a that communicates with each other in the direction of arrow A and supplies a cooling medium. A cooling medium outlet communication hole 34b for discharging the cooling medium is provided at the other end edge in the short side direction.

  As shown in FIG. 1, a fuel gas flow path (reactive gas) that connects a fuel gas inlet communication hole 32 a and a fuel gas outlet communication hole 32 b to the surface 14 a of the first separator 14 facing the electrolyte membrane / electrode structure 16. Channel) 36 is formed. The fuel gas channel 36 has a plurality of wave-like channel grooves 36a extending in the direction of arrow C, and an inlet buffer unit 38 having a plurality of embosses in the vicinity of the inlet and the outlet of the fuel gas channel 36, respectively. And an outlet buffer 40 is provided.

  On the surface 14b of the first separator 14, a plurality of flow channel grooves 44a that are part of the cooling medium flow channel 44 that communicates the cooling medium inlet communication hole 34a and the cooling medium outlet communication hole 34b are formed. An inlet buffer portion 46a and an outlet buffer portion 48a each having a plurality of embosses are provided in the vicinity of the inlet and the outlet of the channel groove 44a.

  On the surface 18a of the second separator 18 facing the electrolyte membrane / electrode structure 16, as shown in FIG. 3, an oxidant gas flow path that connects the oxidant gas inlet communication hole 30a and the oxidant gas outlet communication hole 30b. (Reactive gas flow path) 50 is formed. The oxidant gas channel 50 has a plurality of wave-like channel grooves 50a extending in the direction of arrow C. An inlet buffer portion 52 and an outlet buffer portion 54 are provided in the vicinity of the inlet and the outlet of the oxidizing gas channel 50.

  As shown in FIG. 1, a plurality of flow channel grooves 44 b that are part of the cooling medium flow channel 44 are formed on the surface 18 b of the second separator 18. An inlet buffer portion 46b and an outlet buffer portion 48b each having a plurality of embosses are provided in the vicinity of the inlet and outlet of the channel groove 44b.

  As shown in FIGS. 1 and 2, first seal members 56 are individually or integrally provided on the surfaces 14 a and 14 b of the first separator 14 so as to go around the outer peripheral edge of the first separator 14. . On the surfaces 18a and 18b of the second separator 18, a second seal member 58 is provided individually or integrally around the outer peripheral edge of the second separator 18.

  The first separator 14 includes a plurality of supply holes 60a that communicate with the fuel gas inlet communication hole 32a and the fuel gas flow path 36, and a plurality of discharge holes that communicate with the fuel gas outlet communication hole 32b and the fuel gas flow path 36. 60b.

  As shown in FIG. 3, the second separator 18 includes an oxidant gas inlet communication hole 30 a and a communication portion between the oxidant gas outlet communication hole 30 b and the oxidant gas flow path 50. A plurality of receiving portions 64a and 64b that form a plurality of outlet side connection flow paths 62b are provided.

  The second separator 18 includes a pipe member extending from the outlet buffer portion 54 to the inside of the oxidant gas outlet communication hole 30b and discharging water remaining in the outlet buffer portion 54 to the oxidant gas outlet communication hole 30b. A drainage passage part) 66 is provided.

  The pipe member 66 has an inlet 66 a that opens to the lowest position 54 a of the outlet buffer portion 54, and the inlet 66 a is configured to expand toward the outlet buffer portion 54.

  The pipe member 66 is bent or curved in a substantially L shape in a straight line or a gentle R shape, and the outlet 66b opens inside the oxidant gas outlet communication hole 30b, that is, in the high speed portion 68 where the flow velocity is high. The outlet 66b is configured to narrow toward the high speed portion 68. The outlet 66b of the pipe member 66 has a discharge port that opens in a direction (substantially orthogonal) to the direction of the oxidizing gas flow in the oxidizing gas outlet communication hole 30b.

  The pipe members 66 provided in the power generation units 12 adjacent to each other are arranged in a staggered manner with respect to the stacking direction.

  As shown in FIG. 1, the first separator 14 has a pipe member (drainage) whose inlet side communicates with the discharge hole 60b disposed at the lowest position and whose outlet side opens into the fuel gas outlet communication hole 32b. (Passage section) 70 is provided. The pipe member 70 is configured similarly to the pipe member 66 described above, and a detailed description thereof is omitted.

  As the power generation units 12 are stacked on each other, a cooling medium flow path 44 is formed between the first separator 14 constituting one power generation unit 12 and the second separator 18 constituting the other power generation unit 12. It is formed.

  The operation of the fuel cell 10 configured as described above will be described below.

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 30a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 32a. Supplied. Further, a cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlet communication hole 34a.

  For this reason, the oxidant gas is introduced into the oxidant gas flow path 50 of the second separator 18 from the oxidant gas inlet communication hole 30a. The oxidant gas moves in the direction of arrow C (the direction of gravity) along the oxidant gas flow path 50 and is supplied to the cathode side electrode 26 of the electrolyte membrane / electrode structure 16.

  On the other hand, as shown in FIG. 2, the fuel gas moves from the fuel gas inlet communication hole 32a to the surface 14a side of the first separator 14 through the supply hole 60a. The fuel gas moves in the gravity direction (arrow C direction) along the fuel gas flow path 36 and is supplied to the anode side electrode 24 of the electrolyte membrane / electrode structure 16 (see FIGS. 1 and 2).

  Therefore, in the electrolyte membrane / electrode structure 16, the oxidant gas supplied to the cathode side electrode 26 and the fuel gas supplied to the anode side electrode 24 are consumed by an electrochemical reaction in the electrode catalyst layer to generate power. Is done.

  Next, the oxidant gas supplied and consumed to the cathode electrode 26 of the electrolyte membrane / electrode structure 16 is discharged in the direction of arrow A along the oxidant gas outlet communication hole 30b. On the other hand, the fuel gas supplied and consumed to the anode side electrode 24 of the electrolyte membrane / electrode structure 16 is led to the surface 14b side of the first separator 14 through the discharge hole 60b. The fuel gas led out to the surface 14b side is discharged to the fuel gas outlet communication hole 32b.

  Further, the cooling medium supplied to the cooling medium inlet communication hole 34a includes a first separator 14 constituting one power generation unit 12 and a second separator constituting the other power generation unit 12, as shown in FIGS. It is introduced into a cooling medium flow path 44 formed between the separator 18.

  For this reason, the cooling medium supplied to the cooling medium flow path 44 from the cooling medium inlet communication hole 34a moves in the direction of arrow B to cool the power generation unit 12, and then is discharged to the cooling medium outlet communication hole 34b.

  In this case, in the first embodiment, as shown in FIG. 3, the second separator 18 extends from the outlet buffer portion 54 to the inside of the oxidant gas outlet communication hole 30 b (high-speed portion 68), and the pipe member 66. Is provided. That is, the outlet 66b of the pipe member 66 is opened inside the oxidant gas outlet communication hole 30b corresponding to the high speed portion 68 where the flow of the oxidant gas is fast.

  Therefore, as shown in FIG. 4, a negative pressure is generated at the outlet 66b of the pipe member 66 due to the flow of the oxidant gas (in the direction of arrow F). For this reason, through the pushing force by the oxidant gas flowing to the outlet buffer part 54 and the negative pressure generated at the outlet 66b by the oxidant gas flow velocity flowing through the oxidant gas outlet communication hole 30b, the outlet buffer part 54 The stagnant water is discharged well.

  Thereby, it is possible to obtain an effect that the accumulated water can be easily and reliably discharged from the surface of the second separator 18 (in the surface of the oxidant gas flow path 50) with a simple and compact configuration. Therefore, it is possible to reliably prevent poor oxidant gas flow and eliminate the need for scavenging with a large flow of oxidant gas to prevent a decrease in power generation efficiency and reliably maintain good power generation performance. Become.

  Further, the outlet 66b of the pipe member 66 is narrowed toward the oxidant gas outlet communication hole 30b, and has an inclination angle of 10 ° to 45 °, for example. For this reason, there exists an advantage that the suction of the water from the exit 66b is performed more reliably. On the other hand, the inlet 66a of the pipe member 66 is widened toward the outlet buffer portion 54 (for example, an inclination angle of 10 ° to 45 °), and stagnant water is smoothly introduced into the inlet 66a to improve drainage. Is easily achieved.

  Furthermore, the pipe members 66 of the power generation units 12 adjacent to each other are arranged in a staggered manner (offset) with respect to the stacking direction. Thereby, the high-speed site | part 68 with a quick flow velocity of the oxidizing agent gas outlet communicating hole 30b can be utilized effectively, and the improvement of drainage property is achieved easily.

  FIG. 5 is an enlarged perspective explanatory view of a pipe member (drainage passage portion) 80 constituting the fuel cell according to the second embodiment of the present invention.

  The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Here, the pipe member 80 can be applied to both the oxidant gas outlet and the fuel gas outlet. The same applies to the third to sixth embodiments described below.

  The pipe member 80 is configured such that the inlet 80a extends toward the outlet buffer portion 54, while the outlet 80b narrows toward the oxidizing gas outlet communication hole 30b. The outlet 80b has a long oval shape along the flow direction of the oxidant gas (the direction of the arrow F) (see FIGS. 5 and 6).

  In 2nd Embodiment comprised in this way, the exit 80b of the pipe member 80 is comprised in the elliptical shape the part which protrudes in the oxidizing agent gas exit communicating hole 30b. For this reason, in particular, there is an advantage that the flow of the oxidant gas in the oxidant gas outlet communication hole 30b is not disturbed, and the flow of the oxidant gas can be made smooth to ensure the cross-sectional area of the flow path. .

  FIG. 7 is an enlarged explanatory view of a main part of a pipe member (drainage passage part) 90 constituting a fuel cell according to the third embodiment of the present invention.

  The pipe member 90 has an elliptical outlet 90b that protrudes into the oxidant gas outlet communication hole 30b (high-speed portion 68), and has an angle θ ° (for example, 3 °) with respect to the gas flow direction (arrow F direction). An inclined end surface 92 is provided which is inclined by ˜45 °. The inclined end surface 92 is inclined in a direction away from the flow direction along the oxidant gas flow direction.

  In the third embodiment configured as described above, an inclined end surface 92 is provided at the outlet 90 b of the pipe member 90. Therefore, there is an advantage that water can be discharged more smoothly from the outlet 90b by the flow of the oxidant gas.

  FIG. 8 is an enlarged explanatory view of a main part of a pipe member (drainage passage portion) 100 constituting a fuel cell according to the fourth embodiment of the present invention.

  The pipe member 100 has an outlet 100b protruding into the oxidant gas outlet communication hole 30b (high speed portion 68), and the outlet 100b is inclined toward the upstream side in the oxidant gas flow direction (arrow F direction). An open end face 102 is provided. A discharge opening 104 is formed on the side surface of the outlet 100b on the downstream side in the gas flow direction.

  In the fourth embodiment configured as described above, the oxidant gas flowing along the oxidant gas outlet communication hole 30b flows under the guide action of the open end face 102 provided at the outlet 100b of the pipe member 100. After being introduced into 100b, it is discharged from the discharge opening 104 to the oxidant gas outlet communication hole 30b. For this reason, a negative pressure can be concentrated on the exit 100b, and there is an effect that drainage is performed more satisfactorily.

  FIG. 9 is an exploded perspective view of the power generation unit 112 constituting the fuel cell 110 according to the fifth embodiment of the present invention.

  The power generation unit 112 includes a first separator 114, an electrolyte membrane / electrode structure 16, and a second separator 116. The first separator 114 and the second separator 116 are constituted by a metal plate, and the drainage passage 118 is integrally constituted by the first separator 114 and the second separator 116.

  The drainage passage portion 118 has a first bent portion 120 formed integrally with the first separator 114 and a second bent portion 122 formed integrally with the second separator 116, and the lower end portion thereof is an oxidizing agent. The gas outlet communication hole 30b is disposed so as to protrude.

  As shown in FIG. 10, the first bent portion 120 is disposed upstream of the second bent portion 122 in the oxidizing gas flow direction of the oxidant gas outlet communication hole 30b, and the first bent portion 120 is The dimension in the width direction (arrow G direction) is set larger than that of the second bent portion 122.

  The first bent portion 120 has a substantially U-shaped cross section and has a function of smoothing the flow of the oxidant gas by curving the corners. Similarly, the second bent portion 122 has a U-shaped cross section, and the drain side nozzle flow path 124 is formed by bringing the opening side end into contact with the inner wall surface of the first bent portion 120.

  In the fifth embodiment configured as described above, the first separator 114 and the second separator 116 are formed of a metal plate, and the first bent portion 120 and the second bent portion 122 are integrated with each other by press molding. Molding.

  When the electrolyte membrane / electrode structure 16 is sandwiched between the first separator 114 and the second separator 116, the first bent portion 120 and the second bent portion 122 overlap each other, and the drainage nozzle flow path 124. Is formed.

  The drainage nozzle flow path 124 is opened inside the oxidant gas outlet communication hole 30b, and the oxidant gas outlet communication hole 30b from the drainage nozzle flow path 124 through a negative pressure generated by the flow of the oxidant gas. There is an advantage that it is possible to drain smoothly.

  FIG. 11 is an exploded perspective view of the power generation unit 132 constituting the fuel cell 130 according to the sixth embodiment of the present invention.

  The power generation unit 132 includes a first separator 134, an electrolyte membrane / electrode structure 16, and a second separator 136. The first separator 134 and the second separator 136 are constituted by a metal plate, and the drainage passage 138 is integrally constituted by the first separator 134 and the second separator 136.

  The drainage passage portion 138 includes a first bending member 140 welded to the first separator 114 and a second bending member 142 welded to the second separator 116, and the lower end portion thereof has an oxidant gas outlet. It protrudes and is arrange | positioned inside the communicating hole 30b.

  In the sixth embodiment configured as described above, the drainage passage portion 138 is configured by the first bending member 140 and the second bending member 142, and the same effect as in the fifth embodiment is obtained. It is done.

  In the first to sixth embodiments, the first separator 14 (114, 134), the electrolyte membrane / electrode structure 16 and the second separator 18 (116, 136) are provided. However, the present invention is not limited to this. For example, a power generation unit having a so-called thinning cooling structure including three separators and two electrolyte membrane / electrode structures may be used.

DESCRIPTION OF SYMBOLS 10, 110, 130 ... Fuel cell 12, 112, 132 ... Electric power generation unit 14, 18, 114, 116, 134, 136 ... Separator 16 ... Electrolyte membrane electrode structure 22 ... Solid polymer electrolyte membrane 24 ... Anode side electrode 26 ... cathode side electrode 30a ... oxidant gas inlet communication hole 30b ... oxidant gas outlet communication hole 32a ... fuel gas inlet communication hole 32b ... fuel gas outlet communication hole 34a ... cooling medium inlet communication hole 34b ... cooling medium outlet communication hole 36 ... Fuel gas flow path 38, 46a, 46b, 52 ... Inlet buffer section 40, 48a, 48b, 54 ... Outlet buffer section 44 ... Cooling medium flow path 50 ... Oxidant gas flow path 66, 70, 80, 90, 100 ... Pipe Member 66a, 80a ... Inlet 66b, 80b, 90b, 100b ... Outlet 68 ... High-speed part 92 ... Inclined end face 102 ... Open end face 104 ... Out openings 118 and 138 ... drainage passage 120, 122 ... bent portion 124 ... drainage nozzle channel 140, 142 ... bending member

Claims (10)

A plurality of power generation units in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of the electrolyte and a separator are stacked, and a fuel gas or an oxidant gas along the electrodes are provided on the electrode facing surface of the separator. A fuel cell is provided with a reaction gas flow path for supplying a certain reaction gas, and provided with a reaction gas communication hole through which the reaction gas flows in the stacking direction,
At the lower end portion of the reaction gas flow path, an outlet buffer portion communicating with the reaction gas communication hole on the outlet side is provided,
A drainage passage portion having an outlet projecting into the reaction gas communication hole on the outlet side, extending from the outlet buffer portion to the inside of the reaction gas communication hole on the outlet side, and staying in the outlet buffer portion A fuel cell comprising: a drainage passage portion that discharges water to be discharged from the outlet of the drainage passage portion to the reaction gas communication hole on the outlet side.   2. The fuel cell according to claim 1, wherein an outlet of the drainage passage has a drainage port that opens in a direction inclined with respect to a gas flow direction of the reaction gas communication hole on the outlet side. . The fuel cell according to claim 1 or 2, wherein the electrolyte / electrode structure and the separator are stacked in a horizontal direction,
The fuel cell according to claim 1, wherein an inlet of the drainage passage portion opens at a lowermost position of the outlet buffer portion.   The fuel cell according to any one of claims 1 to 3, wherein the drainage passage portions provided in the power generation units adjacent to each other are arranged in a staggered manner with respect to the stacking direction. Fuel cell.   5. The fuel cell according to claim 1, wherein an outlet of the drainage passage is configured to be narrowed toward the reaction gas communication hole on an outlet side. 6. .   6. The fuel cell according to claim 1, wherein an inlet of the drainage passage portion is configured to expand toward the outlet buffer portion. 6.   7. The fuel cell according to claim 1, wherein the drainage passage portion is arranged to extend from the outlet buffer portion to the inside of the reaction gas communication hole on the outlet side. A fuel cell comprising:   8. The fuel cell according to claim 7, wherein at least a portion of the pipe member that enters the reaction gas communication hole on the outlet side has an elliptical shape that is long in the flow direction of the reaction gas. Fuel cell. The fuel cell according to any one of claims 1 to 6, wherein the separator is constituted by a metal plate,
The drainage passage portion is configured integrally with a first bent portion of one of the separators adjacent to each other and a second bent portion of the other separator overlapping each other.   10. The fuel cell according to claim 9, wherein the first bent portion on the upstream side in the reaction gas flow direction of the reaction gas communication hole on the outlet side is set to a size larger than the second bent portion on the downstream side in the reaction gas flow direction. A fuel cell.

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