JP2008103241A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent inflow of condensed water by a simple and convenient constitution in a fuel cell. <P>SOLUTION: The bottom part of an air inlet hole of an air side fastening plate 19 is arranged more downside in the gravity direction than the bottom part of an air inlet port 30, and the bottom part of an air outlet hole 27 of the air side fastening plate 19 is arranged at the same as the bottom part of an air outlet port 32 or more downside in the gravity direction than that. Moreover, the bottom part of a hydrogen inlet hole 26 of a hydrogen side fastening plate 20 is arranged more downside in the gravity direction than the bottom part of a hydrogen inlet port 46, and the bottom part of a hydrogen outlet hole 28 of the hydrogen side fastening plate 20 is arranged at the same as the bottom part of a hydrogen outlet port 48 or more downside in the gravity direction than that. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a structure of a fuel cell.

  In a fuel cell, both sides of a membrane electrode assembly (MEA) constituted by a fuel side electrode having a catalyst layer on both sides of an electrolyte made of a polymer ion exchange membrane and an oxidant side electrode are opposed to each other by a separator. A plurality of unit cells configured as described above are stacked to form a cell stack (stack) that can obtain a predetermined voltage.

  In such a fuel cell, a fuel gas such as hydrogen is supplied to the fuel side electrode, and an oxidant gas such as oxygen gas or air is supplied to the oxidant side electrode. Hydrogen in the fuel gas supplied to the fuel side electrode is hydrogen ionized in the catalyst layer, and moves to the oxidant side electrode through the appropriately humidified electrolyte. Electrons generated in the meantime are taken out to an external circuit and used as direct current electric energy. In the oxidant side electrode, hydrogen ions, electrons and oxygen react to generate water.

  In this case, the electrolyte made of the polymer ion exchange membrane needs to be sufficiently humidified to maintain ion permeability. For this reason, it is configured to humidify the electrolyte by humidifying the oxidant gas and the fuel gas using a gas humidifier provided outside the fuel cell and sending them as water vapor to the stack of the fuel cell. ing.

  In general, a fuel cell generally has an optimum operating temperature of about 80 ° C., but when the temperature of the fuel cell is lower than this, the fuel cell is generated by moisture or reaction introduced as water vapor into the fuel cell stack. In some cases, the moisture is in the form of water droplets in the gas flow paths in the fuel cell stack, partially blocking the gas flow paths of the fuel gas and the oxidant gas. As described above, when a part of the gas flow path in the fuel cell stack is blocked by water droplets, the oxidant gas or the fuel gas is not sufficiently supplied to each unit cell of the fuel cell stack, and the fuel gas which is a reactive gas In addition, there is a problem that the diffusibility of the oxidant gas to the catalyst electrode layer is lowered and the power generation performance is deteriorated.

  To solve such a problem, the inlet of the drainage portion communicating with the fuel gas discharge internal manifold of the fuel cell stack is set to the same or lower position than the lowest position of the fuel gas discharge internal manifold. In addition, as the drainage portion extends downward from the inlet, the water droplets discharged to the fuel gas discharge internal manifold are smoothly drained from the drainage portion to the outside of the fuel cell stack, and the unit cell ( There has been proposed a method for preventing water droplets from staying in the power generation cell (see, for example, Patent Document 1).

  Further, in the fuel cell, humidification having a dew point is performed so that moisture supplied to the oxidant gas or fuel gas for humidification does not dew inside the fuel cell stack. However, when the temperature of the fuel gas or oxidant gas supply piping is lower than the temperature of the fuel cell stack, condensation of water vapor may occur in the piping and water droplets may flow into the fuel cell stack.

  For this reason, an enlarged portion is provided in the fuel gas or oxidant gas supply pipe, and water droplets condensed in the pipe are prevented from flowing into the gas flow path in the fuel cell stack by a step projecting downward from the enlarged portion. Has been proposed (see, for example, Patent Document 2).

  Also, condensate water that is condensed or generated in the fuel cell supply pipe, fuel gas exhaust pipe, air supply pipe, and air exhaust pipe to the end plate of each fuel cell in these pipes or from the fuel cell stack And a reservoir that protrudes downward to temporarily store the generated water, and a drain pipe is connected to the reservoir through an electromagnetic valve that is a drain valve that opens and closes by an electrical signal, so that the water accumulated in the reservoir is external to the fuel cell. A method for draining water has been proposed (see, for example, Patent Document 3).

JP 2004-327059 A JP 2000-90954 A JP 2003-177871 A

  In the prior art described in the above-mentioned Patent Document 1, the water droplets discharged to the fuel gas discharge internal manifold inside the fuel cell stack are smoothly drained to the outside of the fuel cell stack, and the unit cell (power generation cell) of the fuel cell Although it is disclosed that water droplets are prevented from staying therein, there is no disclosure of preventing water droplets in fuel gas or oxidant gas from flowing into the fuel cell stack.

  In Patent Documents 2 and 3, a fuel gas or oxidant gas supply pipe outside the fuel cell, or a step or a water reservoir that protrudes downward is provided at a connection portion to the end plate of these fuel cells. Although it is disclosed that water droplets condensed inside the fuel cell stack are prevented from flowing into the gas flow path in the fuel cell stack, it is necessary to provide another part for storing the water droplets outside the fuel cell stack. There is a problem that the flow path structure is complicated and the pressure loss increases.

  On the other hand, stationary fuel cells that require high efficiency reduce the power of auxiliary equipment such as compressors by reducing the pressure of each gas flow path. For this reason, it is required to reduce the flow path pressure loss of fuel gas and oxidant gas as much as possible.

  An object of the present invention is to prevent the flow of condensed water into a fuel cell with a simple configuration.

  The fuel cell according to the present invention includes a membrane electrode assembly, a reaction gas channel that is disposed in contact with both surfaces of the membrane electrode assembly, and a reaction gas channel that supplies a reaction gas supplied to each surface of the membrane electrode assembly, and the reaction gas channel. A cell stack in which a plurality of unit cells including a separator having an inlet port connected to each other, a reaction gas supply path formed by each of the inlet ports and penetrating through the cell stack, and the cell stack An end cell disposed at an end; an end member stacked on at least one end of the cell stack; and a reaction gas supply hole provided in the end member and communicating with the reaction gas supply path. A fuel cell comprising: a first member that is one of the end cell and the end member; and a first member of the end member that is upstream of the first reaction gas than the first member. Part 2 And a peripheral edge of the reaction gas supply hole of the second member is wider in a direction perpendicular to the reaction gas flow direction than an inlet port of the first member or a peripheral edge of the reaction gas supply hole. It is characterized by that. In the fuel cell of the present invention, the bottom part of the reaction gas supply hole of the second member is preferably lower in the direction of gravity than the inlet port of the first member or the bottom part of the reaction gas supply hole. It is also preferable that the first member and the second member are adjacent to each other.

  The fuel cell according to the present invention includes a membrane electrode assembly, a reaction gas channel that is disposed in contact with both surfaces of the membrane electrode assembly, and a reaction gas channel that supplies a reaction gas supplied to each surface of the membrane electrode assembly, and the reaction gas channel. A cell stack in which a plurality of unit cells including a separator having an inlet port connected to each other, a reaction gas supply path formed by each of the inlet ports and penetrating through the cell stack, and the cell stack In the fuel cell comprising: an end member stacked at least on one end side; and a reaction gas supply hole provided in the end member and communicating with the reaction gas supply path, the reaction gas supply hole of the end member A peripheral edge extends in a direction perpendicular to the reaction gas flow direction rather than a peripheral edge of the inlet port. The fuel cell of the present invention comprises a first end member on the cell stack side, and a second end member on the upstream side of the reaction gas with respect to the first end member, Preferably, the peripheral edge of the reaction gas supply hole of the second end member is wider in the direction perpendicular to the reaction gas flow direction than the peripheral edge of the reaction gas supply hole of the first end member. It is also preferable that the bottom portion of the reaction gas supply hole is lower in the gravity direction than the bottom portion of the inlet port, and the first end member and the second end member are adjacent to each other. And the bottom of the reaction gas supply hole of the second end member is below the bottom of the reaction gas supply hole of the first end member in the direction of gravity. This is also preferable.

  The fuel cell according to the present invention includes a membrane electrode assembly, a reaction gas channel that is disposed in contact with both surfaces of the membrane electrode assembly, and a reaction gas channel that supplies a reaction gas supplied to each surface of the membrane electrode assembly, and the reaction gas channel. A separator having an inlet port and an outlet port connected to each other, a cell stack including a plurality of unit cells, a reaction gas supply path formed by each of the inlet ports and passing through the cell stack, A reaction gas discharge path formed by each outlet port and penetrating the cell stack, a fastening plate stacked on both ends of the cell stack, and a reaction provided on one of the fastening plates and communicating with the reaction gas supply path A fuel cell comprising: a gas inlet hole; and a reactive gas outlet hole provided in one or the other of the fastening plates and communicating with the reactive gas discharge passage, wherein the reactive gas of the fastening plate The bottom of the mouth hole is below the bottom of the reaction gas inlet port in the direction of gravity, and the bottom of the reaction gas outlet hole of the fastening plate is the same as or lower than the bottom of the reaction gas outlet port. It is characterized by being down in the direction.

  In the fuel cell of the present invention, the reaction gas introduction hole and the reaction gas outlet hole, which are stacked between the cell stack and the fastening plate and communicate with the reaction gas inlet hole and the reaction gas supply path, A collector plate having a reactant gas outlet hole communicating with the reactant gas discharge path, and a bottom portion of the reactant gas introduction hole of the collector plate is the same as or lower than a bottom portion of the reactant gas inlet port The bottom of the reaction gas outlet hole of the current collector plate is preferably the same as or lower than the bottom of the reaction gas outlet port in the direction of gravity. A reaction that is laminated between the current collector plate and the fastening plate and communicates the reaction gas inlet hole, the reaction gas outlet hole, and the reaction gas discharge passage that communicates the reaction gas inlet hole and the reaction gas supply path. It has an insulating plate with a gas outlet hole, The bottom of the reaction gas introduction hole of the insulating plate is the same as or lower than the bottom of the reaction gas inlet port in the gravitational direction, and the bottom of the reaction gas outlet hole of the insulating plate is the reaction gas outlet port It is also preferable that it is the same as the bottom part of the bottom part or below the bottom part in the direction of gravity.

  The present invention has an effect that it is possible to prevent the flow of condensed water into the fuel cell with a simple configuration.

  A preferred embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the fuel cell 11 is a cell configured such that a predetermined voltage can be obtained by stacking a plurality of unit cells 13 formed by sandwiching both sides of a membrane electrode assembly (MEA) with a separator. The laminated body 14, the current collecting plates 15 and 16 for taking out the generated power laminated on both sides of the cell laminated body 14, and the insulating plates 17 and 18 laminated on both sides of the current collecting plate are arranged on the oxidant side electrode side. The air-side fastening plate 19 and the hydrogen-side fastening plate 20 laminated on the fuel-side electrode side are integrally fastened. The current collecting plates 15 and 16, the insulating plates 17 and 18, the air side fastening plate 19, and the hydrogen side fastening plate 20 are end members of the cell stack 14.

  Each unit cell 13 is provided with an air inlet port 30 and an air outlet port 32 penetrating each unit cell. Further, the air-side current collecting plate 15 and the insulating plate 17 are also provided with air inlet holes 30a ′ and 30a and air outlet holes 32a ′ and 32a having the same shape as the air inlet port 30 and air outlet port 32 of each unit cell 13, respectively. It has been. The ports 30 and 32 of each unit cell 13 are substantially the same size and arranged at the same height, and an air supply path 29 and an air discharge path 31 extending in the stacking direction of the unit cells 13 by stacking the unit cells 13. Configure. The air supply path 29 communicates with the air introduction holes 30 a ′ and 30 a provided in the current collector plate 15 and the insulating plate 17 and the air inlet hole 25 provided in the air side fastening plate 19, and the air discharge path 31. Are communicated with the air outlet holes 32 a ′ and 32 a provided in the current collecting plate 15 and the insulating plate 17 and the air outlet holes 27 provided in the air side fastening plate 19. An air inlet pipe 21 that communicates with the air inlet hole 25 and an air outlet pipe 23 that communicates with the air outlet hole 27 are provided on the end surface of the air-side fastening plate 19. Here, the stacking direction is a substantially horizontal direction, the air inlet port 30 side is the upper side in the gravity direction, and the side with the air outlet port 32 is the lower side in the gravity direction. The air introduction holes 30a, 30a ′ and the air inlet hole 25 communicate with the air inlet port 31 to form an air supply hole which is a reaction gas supply hole. The air outlet holes 32a, 32a ′ and the air outlet hole 27 The air outlet port 32 communicates with the air outlet port 32 to form an air outlet hole which is a reactive gas outlet hole.

  The peripheral edge of the air inlet hole 25 of the air side fastening plate 19 extends in a direction perpendicular to the gas flow direction from the peripheral edge of each air inlet port 30 of each unit cell 13, and the bottom thereof is each air of each unit cell 13. The bottom of the inlet port 30 and the current collecting plate 15 and the air introducing holes 30a ′ and 30a of the insulating plate 17 are disposed so as to be positioned below the bottom in the direction of gravity. With this arrangement, there is a step between the bottom of the air inlet hole 25 of the air-side fastening plate 19 and the bottom of the air introduction hole 30 a of the insulating plate 17. The bottom of the air outlet hole 27 of the air side fastening plate 19 is the bottom of each air outlet port 32 of each unit cell 13 and the bottom of each of the air outlet holes 32a ′ and 32a of the current collector plate 15 and the insulating plate 17. They are arranged so as to have substantially the same height, and there is no step between the air outlet hole 27 of the air side fastening plate 19 and the bottom of the air outlet hole 32a of the insulating plate 17.

  Each unit cell 13 is provided with a hydrogen inlet port 46 and a hydrogen outlet port 48 penetrating each unit cell. Further, the hydrogen-side current collecting plate 16 and the insulating plate 18 are also provided with hydrogen inlet holes 46a and hydrogen outlet holes 48a having the same shape as the hydrogen inlet port 46 and the hydrogen outlet port 48 of each unit cell 13, respectively. The ports 46 and 48 of each unit cell 13 are substantially the same size and arranged at the same height, and a hydrogen supply path 45 and a hydrogen discharge path 47 extending in the stacking direction of the unit cells 13 by stacking the unit cells 13. Configure. The hydrogen supply passage 45 communicates with the hydrogen introduction holes 46 a ′ and 46 a provided in the current collector plate 16 and the insulating plate 18 and the hydrogen inlet hole 26 provided in the hydrogen side fastening plate 20, and a hydrogen discharge passage 47. Is communicated with the hydrogen outlet holes 48a ′, 48a provided in the current collector plate 16 and the insulating plate 18 and the hydrogen outlet holes 28 provided in the hydrogen side fastening plate 20. A hydrogen inlet pipe 22 communicating with the hydrogen inlet hole 26 and a hydrogen outlet pipe 24 communicating with the hydrogen outlet hole 28 are provided on the end face of the hydrogen side fastening plate 20. The hydrogen introduction holes 46a and 46a ′ and the hydrogen inlet hole 26 communicate with the hydrogen inlet port 46 to form a hydrogen supply hole which is a reaction gas supply hole. The hydrogen outlet holes 48a and 48a ′ and the hydrogen outlet hole 28 The hydrogen discharge port which is the reaction gas discharge hole is configured to communicate with the hydrogen outlet port 48.

  The bottom of the hydrogen inlet hole 26 of the hydrogen side fastening plate 20 is more gravity than the bottom of each hydrogen inlet port 46 of each unit cell 13 and the bottom of each hydrogen introduction hole 46a ', 46a of the current collector plate 16 and insulating plate 18. It arrange | positions so that it may be located in the direction lower side. With this arrangement, there is a step between the bottom of the hydrogen inlet hole 26 of the hydrogen side fastening plate 20 and the bottom of the hydrogen introduction hole 46 a of the insulating plate 18. Further, the hydrogen outlet hole 28 of the hydrogen side fastening plate 20 has a bottom part at the bottom part of each hydrogen outlet port 48 of each unit cell 13 and the bottom part of each hydrogen outlet hole 48a ', 48a of the current collector plate 16 and insulating plate 18. Arranged so as to be substantially the same height, there is no step between the hydrogen outlet hole 28 of the hydrogen side fastening plate 20 and the bottom of the hydrogen outlet hole 48a of the insulating plate 18.

  FIG. 2 is a side view of the fuel cell 11 on the air side. As shown in FIG. 2, the air inlet hole 25 and the air outlet hole 27 provided in the air side fastening plate 19 are circular, and the air inlet port 30, the air outlet port 32 and the current collector plate 15 of each unit cell 13, The air introduction holes 30 a ′ and 30 a and the air outlet holes 32 a ′ and 32 a of the insulating plate 17 are both oblong and long circular, and an air flow path 41 for flowing air from the air inlet port 30 to the air outlet port 32 in the air-side separator. Is provided. The diameter of the air inlet hole 25 is larger than the vertical width of the air inlet port 30 and the air introduction holes 30a ′, 30a, that is, the width in the gravitational direction. 30. The center positions of the air introduction holes 30a ′ and 30a in the gravity direction are substantially the same height, and the bottom of the air inlet hole 25 is lower than the bottom of the air inlet port 30 and the air introduction holes 30a ′ and 30a in the gravity direction. It is arranged to be on the side. If the bottom part of the air inlet hole 25 is arranged to be lower in the gravity direction than the bottom part of the air inlet port 30 and the air introduction holes 30a ′, 30a, the center position of the air inlet hole 25 and the air The center positions of the inlet port 30 and the air introduction holes 30a′30a in the gravity direction are not limited to the same height. The diameter of the air outlet hole 27 is larger than the vertical width of the air outlet port 32 and the air outlet holes 32a ′ and 32a, that is, the width in the direction of gravity, but the bottom of the air outlet hole 27 is the air outlet port 32 and the air outlet hole. 32a 'and 32a are arranged so as to have substantially the same height.

  FIG. 3 is a side view of the hydrogen side of the fuel cell 11. As shown in FIG. 3, the hydrogen inlet hole 26 and the hydrogen outlet hole 28 provided in the hydrogen side fastening plate 20 are circular, and the hydrogen inlet port 46, the hydrogen outlet port 48 and the current collector plate 16 of each unit cell 13, The hydrogen introduction holes 46a ′ and 46a and the hydrogen lead-out holes 48a ′ and 48a of the insulating plate 18 are both vertically long rectangles, and a hydrogen flow path 43 for flowing hydrogen from the hydrogen inlet port 46 to the hydrogen outlet port 48 is provided on the hydrogen side separator. Is provided. The hydrogen inlet hole 26 is disposed at a position such that the bottom of the hydrogen inlet port 46 and the hydrogen inlet holes 46a 'and 46a are located below the gravitational direction. The hydrogen outlet hole 28 is arranged at a position where the bottom of the hydrogen outlet port 48 and the hydrogen outlet holes 48a ', 48a on the lower side in the gravitational direction and the bottom thereof have substantially the same height.

  Next, the flow path structure of the fuel cell 11 and the flow of air and hydrogen will be described. FIG. 4 shows a cross section of the fuel cell 11 around the air side fastening plate 19. As shown in FIG. 4, each unit cell 13 has a membrane electrode assembly in which a fuel side electrode having a catalyst layer on both sides of an electrolyte made of a polymer ion exchange membrane and an oxidant side electrode are arranged to face each other. Both sides of 35 are sandwiched between an air side separator 33 and a hydrogen side separator 37. The air side separator 33 is disposed on the oxidant side electrode side of the membrane electrode assembly, and the hydrogen side separator 37 is disposed on the fuel side electrode side. The air-side separator 33 is provided with an air channel 41 for flowing air from the air inlet port 30 to the air outlet port 32 on a surface in contact with the membrane electrode assembly 35 and a cooling water channel 39 provided on the opposite side of the air channel. . As shown in FIG. 5, the air flow path 41 has a large number of parallel flows for flowing air from the air inlet port 30 disposed on the upper side in the gravity direction toward the air outlet port 32 disposed on the lower side in the gravity direction. It is composed of roads. Further, as shown in FIG. 6, the hydrogen side separator 37 is provided with a vertically long rectangular hydrogen inlet port 46 and a hydrogen outlet port 48 provided on the left and right sides, and a surface in contact with the membrane electrode assembly 35 from the hydrogen inlet port 46. A hydrogen flow path 43 for flowing hydrogen to the hydrogen outlet port 48 is provided. The hydrogen flow path 43 is connected to the ports 46 and 48 substantially horizontally, and in the central portion of the fuel cell 11 is a large number of parallel flow paths that flow downward in the direction of gravity in the same manner as the air flow path. The air-side separator 33 and the hydrogen-side separator 37 are each provided with a cooling water inlet port 51 and a cooling water outlet port 53 that constitute a cooling water supply path and a discharge path.

  As shown in FIG. 4, the air introduced from the air inlet pipe 21 provided in the air-side fastening plate 19 contains moisture condensed in the air inlet pipe 21 in the form of water droplets. Since such water droplets have a higher specific gravity than air, the water droplets flow toward the fuel cell 11 along the bottom of the air inlet tube 21. Then, the water droplets entering with the air from the air inlet pipe 21 flow toward the unit cell 13 of the fuel cell 11 through the bottom of the air inlet hole 25 of the air side fastening plate 19 whose bottom is substantially the same height. And the bottom part of the air introduction hole 30a of the insulating plate 17 provided in contact with the downstream side of the air flow direction of the air side fastening plate 19 is disposed above the bottom part of the air inlet hole 25 in the gravity direction. . As described above, the contact surface of the insulating plate 17 provided adjacent to the air side fastening plate 19 that contacts the air side fastening plate 19 is exposed to the end face of the air inlet hole 25 of the air side fastening plate 19. . That is, the wall surface of the reaction gas channel is configured to be shifted between adjacent members. For this reason, the water droplets flowing along the bottom of the air inlet hole 25 are blocked by the insulating plate 17, and the air introducing hole 30a of the current collecting plate 15 is downstream of the insulating plate 17 and the air flow. ′ And the air supply passage 29 constituted by the air inlet ports 30 provided in the air side separator 33 and the hydrogen side separator 37, respectively, do not enter. For this reason, it is possible to reduce the occurrence of clogging due to water drops clogging the air flow path 41 of the air-side separator 33.

  On the other hand, water in the form of water vapor is supplied together with air from the air inlet hole 25 of the air-side fastening plate 19 through the air introduction holes 30a and 30a ′ provided in the insulating plate 17 and the current collector plate 15, respectively. The air enters the air supply path 29 formed in the stacking direction by the air inlet ports 30 provided in the side separators 37 respectively. And it flows in into the air flow path 41 from the air inlet port 30 of the air side separator 33 which comprises the air supply path 29, and flows toward the gravity direction lower side. Since moisture is generated in the air flowing through the air flow path 41 by the electrochemical reaction of the fuel cell 11, the amount of moisture increases toward the downstream. Exhaust air containing a large amount of moisture is discharged from the air flow path 41 to the air outlet port 32. The discharged air is supplied from the air discharge path 31 formed in the stacking direction by the air outlet port 32 provided in the air side separator 33 and the hydrogen side separator 37, respectively, to the current collector plate 15 and the insulating plate 17, respectively. The air is discharged from the air outlet hole 27 of the air side fastening plate 19 to the outside of the fuel cell 11 through the lead-out holes 32a ′ and 32a. Since this exhaust air contains a large amount of moisture, the moisture may flow through the bottom of the air discharge passage 31 in the form of water droplets, but the bottom of the air outlet hole 27 of the air side fastening plate 19 and the air discharge passage 31 The bottom of the air outlet port 32 provided in each of the air side separator 33 and the hydrogen side separator 37 to be formed and the bottom of the air outlet holes 32a ′ and 32a provided in the current collecting plate 15 and the insulating plate 17 are substantially the same height. Thus, the water droplets can be discharged to the outside of the fuel cell 11 without accumulating in the air discharge passage 31 and the air outlet holes 32a ′ and 32a.

  The flow of hydrogen is the same as the flow of air. As shown in FIG. 1, water droplets contained in hydrogen introduced from a hydrogen inlet pipe 22 provided on the hydrogen side fastening plate 20 flow toward the fuel cell 11 along the bottom of the hydrogen inlet pipe 22. . Then, the water droplets entering together with hydrogen from the hydrogen inlet pipe 22 flow toward the unit cell 13 of the fuel cell 11 through the bottom of the hydrogen inlet hole 26 of the hydrogen side fastening plate 20 whose bottom is substantially the same height. And the bottom part of the hydrogen introduction hole 46a of the insulating plate 18 provided in contact with the downstream side in the hydrogen flow direction of the hydrogen side fastening plate 20 is disposed above the bottom part of the hydrogen inlet hole 26 in the gravity direction. Therefore, water droplets flowing along the bottom of the hydrogen inlet hole 26 are blocked by the insulating plate 18 and do not enter the hydrogen supply path 45 of the fuel cell 11. As a result, it is possible to reduce clogging caused by water droplets clogging the hydrogen flow path of the hydrogen separator.

  On the other hand, water in the form of water vapor is supplied together with hydrogen from the hydrogen inlet hole 26 of the hydrogen side fastening plate 20 through the hydrogen introduction holes 46a and 46a 'provided in the insulating plate 18 and the current collector plate 16, respectively, to the air side separator and the hydrogen side. The hydrogen inlet port 46 provided in each separator enters the hydrogen supply path 45 formed in the stacking direction. Then, as shown in FIG. 6, hydrogen flows in a substantially horizontal direction from the hydrogen inlet port 46 of the hydrogen separator constituting the hydrogen supply path 45 into the hydrogen flow path, and then the flow is directed downward in the direction of gravity. Further, the flow is changed horizontally toward the hydrogen outlet port 48, and the discharged hydrogen containing moisture is discharged from the hydrogen flow path 43 to the hydrogen outlet port 48. As shown in FIG. 1, discharged hydrogen is discharged from the hydrogen discharge passage 47 through the hydrogen outlet holes 48 a and 48 a ′ to the outside of the fuel cell 11 through the hydrogen outlet hole 28 of the hydrogen side fastening plate 20. Since the discharged hydrogen contains moisture, the moisture may flow through the bottom of the hydrogen discharge passage 47 in the form of water droplets, but forms a hydrogen discharge passage 47 with the bottom of the hydrogen outlet hole 28 of the hydrogen side fastening plate 20. Since the bottom of the hydrogen outlet port 48 and the bottom of the hydrogen outlet holes 48a and 48a 'provided in the hydrogen side separator and the like are arranged at substantially the same height, the water droplets are placed in the hydrogen discharge passage 47 and the hydrogen. The fuel can be discharged outside the fuel cell 11 without accumulating in the lead-out holes 48a and 48a ′.

  In the embodiment described above, the bottoms of the air inlet holes 25 and the hydrogen inlet holes 26 provided in the fastening plates 19 and 20 are respectively connected to the insulating plates 17 and 18 and the current collector plates 15 and 16. The bottoms of the introduction holes 30a and 30a ′, the hydrogen introduction holes 46a and 46a ′, the air inlet port 30 provided in the air side separator 33 and the hydrogen side separator 37, and the bottoms of the hydrogen inlet port 46, respectively. Due to the simple structure of being disposed on the side, it is possible to prevent the condensed water flowing in the air supply passage 29 and the hydrogen supply passage 45 inside the fuel cell 11 from flowing into the condensed water. In addition, the air outlet holes 27 and 32a ′ provided in the insulating plates 17 and 18 and the current collecting plates 15 and 16, respectively, at the bottoms of the air outlet holes 27 and the hydrogen outlet holes 28 provided in the fastening plates 19 and 20, With a simple structure in which the bottoms of the hydrogen outlet holes 48a, the air side separator 33, the air outlet port 32 provided in the hydrogen side separator 37, and the bottoms of the hydrogen outlet port 48 are arranged at substantially the same height, Water droplets are discharged outside the fuel cell 11 without accumulating in the air supply / discharge path 31, the air outlet holes 32 a and 32 a ′, the hydrogen outlet path 47, and the hydrogen outlet holes 48 a and 48 a ′ inside the fuel cell 11. There is an effect that can be. A typical fuel cell 11 includes an air side fastening plate 19 provided with an air inlet hole 25 and an air outlet hole 27, a hydrogen side fastening plate 20 provided with a hydrogen inlet hole 26 and a hydrogen outlet hole 28, and Air introduction holes 30a and 30a ′, air introduction holes 32a and 32a ′, hydrogen introduction holes 46a and 46a ′, hydrogen introduction holes 48a and 48a ′, and air provided in the insulating plates 17 and 18 and the current collecting plates 15 and 16, respectively. Air inlet port 30, air outlet port 32, hydrogen inlet port 46, and hydrogen outlet port 48 provided in the side separator 33 and hydrogen side separator 37, respectively, and a new member is added to prevent inflow of condensed water With the simple structure that does not require the inflow of condensed water, it is possible to effectively prevent the inflow of condensed water. Furthermore, since an additional member is not required, an increase in pressure loss due to the structure for preventing the inflow of condensed water can be reduced, and the efficiency of the fuel cell 11 can be improved.

  The second embodiment will be described with reference to FIGS. Parts similar to those in FIGS. 1 to 6 described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIGS. 7A and 7B, in this embodiment, the vertical widths of the peripheral edges of the air introduction holes 30a and 30a ′ provided in the insulating plate 17 and the current collecting plate 15 are the air side. The width of the peripheral edge of the air inlet port 30 provided in each of the separator 33 and the hydrogen side separator 37 is wider, and the bottom thereof is substantially the same height as the bottom of the air inlet hole 25 of the air side fastening plate 19. . Further, the bottoms of the air introduction holes 30a and 30a ′ provided in the insulating plate 17 and the current collecting plate 15 are more in the direction of gravity than the bottoms of the air inlet ports 30 provided in the air side separator 33 and the hydrogen side separator 37, respectively. It is arranged to be on the lower side.

  With this configuration, the condensed water flowing in from the air inlet pipe 21 flows from the bottom of the air inlet hole 25 to the bottom of the air introduction holes 30a and 30a ′ of the insulating plate 17 and the current collector plate 15. The bottom of the air inlet port 30 of the side separator 33 is disposed above the bottom of the air inlet hole 25 in the direction of gravity from the bottom of the air introduction holes 30 a and 30 a ′ of the insulating plate 17 and the current collector plate 15. In this way, the contact surface of the air-side separator 33 provided adjacent to the current collecting plate 15 and contacting the current collecting plate 15 is exposed to the end surface of the air introduction hole 30a 'of the current collecting plate 15. That is, the wall surface of the reaction gas channel is configured to be shifted between adjacent members. For this reason, water droplets flowing along the bottom of the air introduction holes 30a and 30a ′ from the bottom of the air inlet hole 25 are blocked by the air-side separator 33 and do not enter the air supply path 29 of the fuel cell 11. . For this reason, it is possible to reduce the occurrence of clogging due to water drops clogging the air flow path 41 of the air-side separator 33.

  As shown in FIGS. 8A and 8B, in this embodiment, the vertical widths of the air outlet holes 32 a and 32 a ′ provided in the insulating plate 17 and the current collector plate 15 are the air-side separator 33. The width of the air outlet port 32 provided in the hydrogen separator 37 is wider than the width of the air outlet port 32, and the bottom of the air outlet port 32 is substantially the same height as the bottom of the air inlet hole 25 of the air side fastening plate 19. The bottoms of the air outlet holes 32a and 32a ′ provided in the insulating plate 17 and the current collecting plate 15 are more in the direction of gravity than the bottoms of the air outlet ports 32 provided in the air side separator 33 and the hydrogen side separator 37, respectively. It is arranged to be on the lower side.

  With this configuration, the moisture of the discharged air discharged from the air flow path 41 to the air discharge path 31 may flow in the form of water droplets in the bottom of the air discharge path 31. The bottom of the air outlet hole 27 and the bottom of the air outlet holes 32a'32a provided in the current collector plate 15 and the insulating plate 17 are provided in the air side separator 33 and the hydrogen side separator 37, respectively, which form the air discharge path 31, respectively. Since the air outlet port 32 is disposed so as to be lower in the gravity direction than the height of the bottom of the air outlet port 32, water droplets do not accumulate in the air discharge passage 31 and the air outlet holes 32a ′ and 32a and go to the outside of the fuel cell 11. It can be made to be discharged.

  The configuration on the hydrogen side and the flow of moisture are the same as the configuration on the air side. As shown in FIG. 9, on the hydrogen side, the vertical widths of the hydrogen introduction holes 46 a and 46 a ′ provided in the insulating plate 18 and the current collector plate 16 are provided in the air side separator 33 and the hydrogen side separator 37, respectively. The width of the hydrogen inlet port 46 is wider, and the bottom of the hydrogen inlet port 46 is substantially the same height as the bottom of the hydrogen inlet hole 26 of the hydrogen side fastening plate 20. Further, the bottoms of the hydrogen introduction holes 46a and 46a ′ provided in the insulating plate 18 and the current collector plate 16 are more in the direction of gravity than the bottoms of the hydrogen inlet ports 46 provided in the air side separator 33 and the hydrogen side separator 37, respectively. It is arranged to be on the lower side.

  The vertical widths of the hydrogen outlet holes 48 a and 48 a ′ provided in the insulating plate 18 and the current collector plate 16 are larger than the widths of the air outlet ports 32 provided in the air side separator 33 and the hydrogen side separator 37. The bottom portion is substantially the same height as the bottom portion of the hydrogen outlet hole 28 of the hydrogen fastening plate 20. Further, the bottoms of the hydrogen outlet holes 48a and 48a ′ provided in the insulating plate 18 and the current collector plate 16 are more in the direction of gravity than the bottoms of the hydrogen outlet ports 48 provided in the air side separator 33 and the hydrogen side separator 37, respectively. It is arranged to be on the lower side.

  With this configuration, the condensed water that has entered from the hydrogen inlet hole 26 is blocked by the hydrogen-side separator 37 and does not enter the hydrogen supply path 45 of the fuel cell 11, similarly to the air side. For this reason, it is possible to reduce the occurrence of clogging due to clogging of water droplets in the hydrogen flow path 43 of the hydrogen side separator 37. Further, water droplets contained in the discharged hydrogen discharged from the hydrogen flow path 43 can be discharged to the outside of the fuel cell 11 without accumulating in the hydrogen discharge path 47 and the hydrogen outlet holes 48a and 48a '.

  In the present embodiment described above, as in the above-described embodiments, the inflow of condensed water can be prevented with a simple configuration, the pressure loss can be reduced, and the efficiency of the fuel cell 11 can be improved. Play.

  A third embodiment will be described with reference to FIGS. Parts similar to those shown in FIGS. 1 to 9 described above are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIGS. 10 (a) and 10 (b), in the present embodiment, the shape of the air introduction holes 30a ′ and 30b provided in the current collector plate 15 and the insulating plate 17 is changed to an air side separator 33, a hydrogen side separator, respectively. 37 has the same shape as the air inlet port 30 provided in each of them, and the position of the bottom part in the gravitational direction is arranged between the bottom part of the air inlet port 30 and the bottom part of the air inlet hole 25. 11 (a) and 11 (b), the air outlet holes 32a 'and 32b provided in the current collector plate 15 and the insulating plate 17 are provided in the air side separator 33 and the hydrogen side separator 37, respectively. The air outlet port 32 has the same shape as that of the air outlet port 32, and is arranged so that the position in the gravity direction of the bottom part is located between the position of the bottom part of the air outlet port 32 and the position of the bottom part of the air outlet hole 27.

  By arranging in this way, the condensed water that has entered from the air inlet pipe 21 is stepped between the bottom of the air inlet hole 25 and the bottom of the air introduction hole 30b of the insulating plate 17 and the air introduction hole 30b ′ of the current collecting plate 15. The air flow path 41 is blocked by water droplets by clogging with a step between the bottom and the bottom of the air inlet port 30 of the air separator 33 so that the condensed water does not enter the air supply path 29 of the fuel cell 11. This can be reduced. Further, water droplets discharged from the air flow path 41 can be discharged to the outside of the fuel cell 11 without accumulating in the air discharge path 31 and the air outlet holes 32b and 32b '.

  The hydrogen side has the same configuration as the air side. As shown in FIG. 12, in the present embodiment, the shape of the hydrogen introduction holes 46b ′ and 46b provided in the current collector plate 16 and the insulating plate 18 is changed to the hydrogen inlet provided in the air side separator 33 and the hydrogen side separator 37, respectively. As the shape of the port 46 is the same as that of the port 46, the position of the bottom in the gravitational direction is arranged between the position of the bottom of the hydrogen inlet port 46 and the position of the bottom of the hydrogen inlet hole 26. 18 are formed in the same shape as the hydrogen outlet port 48 provided in each of the air-side separator 33 and the hydrogen-side separator 37, and the position of the bottom in the direction of gravity is set as the hydrogen outlet. It is arranged so as to come between the position of the bottom of the port 48 and the position of the bottom of the hydrogen outlet hole 28.

  By arranging in this way, the condensed water that has entered from the hydrogen inlet pipe 22 is stepped between the bottom of the hydrogen inlet hole 26 and the bottom of the hydrogen introduction hole 46b of the insulating plate 18 and the hydrogen introduction hole 46b ′ of the current collector plate 16. The hydrogen flow path 43 is blocked by water droplets by clogging by a step between the bottom and the bottom of the hydrogen inlet port 46 of the hydrogen separator 37 so that the condensed water does not enter the hydrogen supply path 45 of the fuel cell 11. This can be reduced. Further, the water droplets discharged from the hydrogen flow path 43 can be discharged to the outside of the fuel cell 11 without accumulating in the hydrogen discharge path 47 and the hydrogen outlet holes 48b and 48b '.

  The present embodiment described above also has an effect that the inflow of condensed water can be prevented with a simple configuration as in the above-described embodiment.

  In each of the above embodiments, the air inlet holes 30a ′, 30a, 30b ′, 30b, the air outlet holes 32a ′, 32a, 32b ′, 32b, the hydrogens of the current collector plates 15, 16 and the insulating plates 17, 18 Although the introduction holes 46a ′, 46a, 46b ′, 46b and the hydrogen outlet holes 48a ′, 48a, 48b ′, 48b have been described as being at the same position, the position of the bottom of each hole of the insulating plate 17 is the current collector. If it is below the position of the bottom of each hole of the plates 17 and 18 in the gravitational direction, the intrusion of condensed water can be prevented, and water droplets can be discharged without accumulating inside the fuel cell 11. , They may not be provided at the same position.

  A fourth embodiment will be described with reference to FIG. The same parts as those in FIGS. 1 to 12 described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 13, in this embodiment, the air inlet hole 25 and the air outlet hole 27 provided in the air side fastening plate 19 are circular, and the air inlet port 30 and the air outlet port 32 of each unit cell 13 are The air inlet holes 30a ′, 30a and the air outlet holes 32 ′, 32a of the current collector plate 15 and the insulating plate 17 are both long and rectangular in a rectangular shape, and air is supplied from the air inlet port 30 to the air outlet port 32 to the separator 33 on the air side. An air flow path 41 is provided. The peripheral edge of the air inlet hole 25 is wider in the direction perpendicular to the gas flow direction than the peripheral edges of the air inlet port 30 and the air introduction holes 30a ′ and 30a. The lateral width of the air inlet port 30 and the air introduction holes 30a ′ and 30a The width of the air inlet hole 25 is wider than that. The air outlet hole 28 is disposed at a position such that the bottom of the air outlet port 32 and the air outlet hole 32a'32a on the lower side in the gravity direction and the bottom thereof have substantially the same height.

  In the present embodiment, as in the first to third embodiments, the air inlet hole 25 of the air-side fastening plate 19 has a bottom at the bottom of each air inlet port 30 of each unit cell 13 or the current collector plate 15, insulation. Although not arranged so as to be positioned below the bottom of each air introduction hole 30a ′, 30a of the plate 17 in the direction of gravity, the inflow of water droplets flowing along the side surface of the air inlet hole 25 is suppressed, Intrusion into the fuel cell can be prevented.

  The present embodiment described above also has an effect that the inflow of condensed water can be prevented with a simple configuration as in the above-described embodiment.

  In the first to fourth embodiments described above, the air side fastening plate 19 is provided with the air inlet hole 25 and the air outlet hole 27, and the hydrogen side fastening plate 20 is provided with the hydrogen inlet hole 26 and the hydrogen outlet hole 28. However, in the present invention, when there is no outlet hole as in a dead-end type fuel cell, or when each inlet hole and each outlet hole are not the same fastening plate, the opposite fastening plate The same can be applied to the case where it is provided.

1 is an elevation view of a fuel cell in an embodiment according to the present invention. It is a side view of the air side of the fuel cell in the embodiment according to the present invention. It is a side view of the hydrogen side of the fuel cell in the embodiment according to the present invention. It is sectional drawing of the air side fastening plate, insulating plate, current collecting plate, air side separator, membrane electrode assembly, and hydrogen side separator of the fuel cell in the embodiment according to the present invention. It is a figure which shows the air flow path side surface of the air side separator of the fuel cell in embodiment which concerns on this invention. It is a figure which shows the hydrogen flow path side surface of the hydrogen side separator of the fuel cell in embodiment which concerns on this invention. Sections of an air side fastening plate, an insulating plate, a current collector plate, an air side separator, a membrane electrode assembly, and a hydrogen side separator on the air inlet side of the fuel cell in the second embodiment according to the present invention, and the air side of the fuel cell It is a side view of Sections of an air side fastening plate, an insulating plate, a current collector plate, an air side separator, a membrane electrode assembly, and a hydrogen side separator on the air outlet side of the fuel cell in the second embodiment according to the present invention, and the air side of the fuel cell It is a side view of It is a side view by the side of the hydrogen of the fuel cell in the 2nd embodiment concerning the present invention. Sections of an air side fastening plate, an insulating plate, a current collector plate, an air side separator, a membrane electrode assembly and a hydrogen side separator on the air inlet side of a fuel cell in a third embodiment according to the present invention, and an air side of the fuel cell It is a side view of Sections of air side fastening plate, insulating plate, current collector plate, air side separator, membrane electrode assembly and hydrogen side separator on the air outlet side of the fuel cell in the third embodiment according to the present invention, and the air side of the fuel cell It is a side view of It is a side view by the side of the hydrogen of the fuel cell in 3rd Embodiment which concerns on this invention. It is a side view by the side of the air of the fuel cell in 4th Embodiment which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Fuel cell, 13 Unit cell, 14 Cell laminated body, 15, 16 Current collecting plate, 17, 18 Insulating plate, 19 Air side fastening plate, 20 Hydrogen side fastening plate, 21 Air inlet pipe, 22 Hydrogen inlet pipe, 23 Air Outlet pipe, 24 Hydrogen outlet pipe, 25 Air inlet hole, 26 Hydrogen inlet hole, 27 Air outlet hole, 28 Hydrogen outlet hole, 29 Air supply path, 30 Air inlet port, 30a, 30a ′, 30b, 30b ′ Air introduction hole , 31 Air discharge path, 32 Air outlet port, 32a, 32a ′, 32b, 32b ′ Air outlet hole, 33 Air side separator, 35 Membrane electrode assembly, 37 Hydrogen side separator, 39 Cooling water flow path, 41 Air flow path, 43 Hydrogen flow path, 45 Hydrogen supply path, 46 Hydrogen inlet port, 46a, 46a ′, 46b, 46b ′ Hydrogen introduction hole, 47 Hydrogen discharge path, 48 Hydrogen Outlet port, 48a, 48a ', 48b, 48b' Hydrogen outlet hole, 51 cooling water inlet port, 53 cooling water outlet port.

Claims (11)

A membrane electrode assembly, a reaction gas channel disposed on both sides of the membrane electrode assembly, and a reaction gas channel for supplying a reaction gas supplied to each surface of the membrane electrode assembly; and an inlet port connected to the reaction gas channel. A cell stack including a plurality of unit cells including a separator,
A reaction gas supply path formed by each of the inlet ports and penetrating the cell stack;
An end cell disposed at an end of the cell stack;
In a fuel cell comprising: an end member stacked on at least one end side of the cell stack; and a reaction gas supply hole provided in the end member and communicating with the reaction gas supply path.
A first member that is one of the end cell and the end member;
A second member on the reactive gas upstream side of the first member among the end members;
In a fuel cell comprising:
A fuel cell, wherein a peripheral edge of the reactive gas supply hole of the second member is wider in a direction perpendicular to the reactive gas flow direction than the peripheral edge of the inlet port or the reactive gas supply hole of the first member. . The fuel cell according to claim 1, wherein
The bottom part of the reactive gas supply hole of the said 2nd member is below a gravity direction rather than the inlet port of the said 1st member, or the bottom part of the reactive gas supply hole. The fuel cell characterized by the above-mentioned. The fuel cell according to claim 1 or 2,
The fuel cell, wherein the first member and the second member are adjacent to each other. A membrane electrode assembly, a reaction gas channel disposed on both sides of the membrane electrode assembly, and a reaction gas channel for supplying a reaction gas supplied to each surface of the membrane electrode assembly; and an inlet port connected to the reaction gas channel. A cell stack including a plurality of unit cells including a separator,
A reaction gas supply path formed by each of the inlet ports and penetrating the cell stack;
In a fuel cell comprising: an end member stacked on at least one end side of the cell stack; and a reaction gas supply hole provided in the end member and communicating with the reaction gas supply path.
The fuel cell according to claim 1, wherein a peripheral edge of the reaction gas supply hole of the end member extends in a direction perpendicular to the reactive gas flow direction rather than a peripheral edge of the inlet port. The fuel cell according to claim 4, wherein
A first end member on the cell laminate side;
A second end member on the upstream side of the reaction gas with respect to the first end member;
With
The peripheral edge of the reactive gas supply hole of the second end member is wider in the direction perpendicular to the reactive gas flow direction than the peripheral edge of the reactive gas supply hole of the first end member. . The fuel cell according to claim 4 or 5,
The bottom part of the said reactive gas supply hole exists in the gravity direction below the bottom part of the said inlet port. The fuel cell characterized by the above-mentioned. The fuel cell according to claim 5, wherein
The fuel cell, wherein the first end member and the second end member are adjacent to each other. The fuel cell according to claim 5 or 7,
The bottom of the reactive gas supply hole of the second end member is located below the bottom of the reactive gas supply hole of the first end member in the direction of gravity. A membrane electrode assembly, a reaction gas channel that is disposed in contact with both surfaces of the membrane electrode assembly and flows a reaction gas supplied to each surface of the membrane electrode assembly, and an inlet port connected to the reaction gas channel A cell stack including a plurality of unit cells including a separator having an outlet port;
A reaction gas supply path formed by each of the inlet ports and penetrating the cell stack;
A reaction gas discharge path formed by each of the outlet ports and penetrating through the cell stack;
Fastening plates laminated on both ends of the cell stack, reactive gas inlet holes provided on one side of the fastening plate and communicating with the reactive gas supply path, and reactive gas discharge provided on one or the other side of the fastening plate A fuel cell comprising a reaction gas outlet hole communicating with the road,
The bottom of the reaction gas inlet hole of the fastening plate is below the bottom of the reaction gas inlet port in the direction of gravity;
The bottom of the reaction gas outlet hole of the fastening plate is the same as or lower than the bottom of the reaction gas outlet port in the direction of gravity;
A fuel cell. The fuel cell according to claim 9, wherein
It is laminated | stacked between the said cell laminated body and the said fastening plate, and connects the reactive gas inlet hole which connects the said reactive gas inlet hole and the said reactive gas supply path, the said reactive gas outlet hole, and the said reactive gas discharge path. A current collector plate with a reaction gas outlet hole;
The bottom of the reactive gas introduction hole of the current collector plate is the same as or lower than the bottom of the reactive gas inlet port in the direction of gravity,
The bottom of the reaction gas outlet hole of the current collector plate is the same as or lower than the bottom of the reaction gas outlet port in the direction of gravity;
A fuel cell. The fuel cell according to claim 9 or 10,
The reaction gas inlet hole, the reaction gas outlet hole, and the reaction gas discharge path that are stacked between the current collector plate and the fastening plate and communicate with the reaction gas inlet hole and the reaction gas supply path communicate with each other. Insulating plate with reaction gas outlet hole,
The bottom part of the reaction gas introduction hole of the insulating plate is the same as or lower than the bottom part of the reaction gas inlet port in the direction of gravity.
The bottom of the reaction gas outlet hole of the insulating plate is the same as or lower than the bottom of the reaction gas outlet port in the direction of gravity;
A fuel cell.

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