JP2008130350A - Fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel battery which controls freezing of moisture inside a manifold of a cell laminated body. <P>SOLUTION: In the fuel battery composed of a lamination of power generating cells and dummy cells, a bottom surface of an exit passage contacting with an air exit manifold 32 of an air-side separator of the power generating cell is at an upper side in a gravity direction than a bottom surface 38 of the air exit manifold 32, and a bottom surface of an exit passage 37a contacting the air exit manifold 32 of a cell-side separator of an air-side dummy cell is at a same position or at a lower side than the bottom surface 38 of the air exit manifold 32. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

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

  A fuel gas flow path is formed in the separator on one side of the cell stack, and an oxidant gas flow path is formed in the separator on the other side. Each separator is provided with an inlet manifold and an outlet manifold connected to the flow paths of the fuel gas and the oxidant gas, respectively. The inlet manifold and the outlet manifold of each separator are arranged at the same position, and are configured to penetrate in the stacking direction by stacking each power generation cell.

  A fuel gas, for example, hydrogen is supplied from the fuel gas inlet manifold, and an oxidant gas, for example, oxygen gas or air is supplied from the oxidant gas inlet manifold. Hydrogen in the fuel gas supplied from the fuel gas inlet manifold to the fuel side electrode through the fuel gas flow path is hydrogen ionized in the catalyst layer and moves to the oxidant side electrode via 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, oxygen, hydrogen ions, and electrons in the oxidant gas supplied from the oxidant gas inlet manifold react to generate water. The water produced by the reaction is discharged from the oxidant gas flow path to the oxidant gas outlet manifold. Unreacted hydrogen is discharged to the fuel gas outlet manifold.

  The water discharged to the oxidant outlet manifold is discharged outside the fuel cell. However, when the water discharge from the fuel cell is insufficient, flooding occurs in the oxidant gas flow path in the power generation cell, and the supply of the oxidant gas to the oxidant side electrode is hindered, resulting in the generation of power. Insufficient or potential drop may occur. For this reason, in order to smoothly drain the oxidant gas flow path from the oxidant gas flow path in the power generation cell to the oxidant outlet manifold, the oxidant outlet manifold has a lower end than the lower end of the oxidant gas flow path. A method of extending the lower end downward in the direction of gravity has been proposed. As a result, water is accumulated in the oxidant manifold to improve drainage from the oxidant gas flow path of the power generation cell to the oxidant outlet manifold (see, for example, Patent Document 1).

  In addition, the lower end height position of the separator inlet and outlet manifolds is set to a position lower than the lower end height position of the opening to the manifold of the reaction gas flow path of the separator, so that the generated water or condensed water generated by the cell reaction Even if it stays in the manifold, it is possible to discharge from the reaction gas flow path of the separator, and a method for preventing deterioration of battery performance has been proposed (for example, see Patent Document 2).

  On the other hand, the conventional cell stack of a fuel cell has a problem that the cell voltage of the end cell decreases during power generation. The reason why this problem occurs is that condensate and impurities (such as metal ions of the system) are likely to enter the cell at the end, causing flooding and contamination, leading to a decrease in cell voltage. Under the influence of external heat, it is easy to be cooled and flooding occurs.

  For this reason, a fuel cell stack structure is proposed in which a dummy cell that does not contribute to power generation is provided at the end of the cell stack of the fuel cell, which has a layer in which a gas flow path is formed but has no MEA. ing. Such a cell stack structure of a fuel cell can suppress a voltage drop due to water flooding or contamination due to impurities in the gas inlet / outlet side cells at the end of the cell stacking direction. Moreover, the influence of external temperature (low temperature) can be relieved to condense water, and flooding can be reduced (see, for example, Patent Document 3).

JP 2006-66225 A JP 2005-259424 A JP 2003-338305 A

  As described above, the prior arts disclosed in Patent Documents 1 and 2 are the outside of the fuel cell stack through the oxidant gas outlet manifold provided in the separator of the fuel cell stack through the oxidant gas outlet manifold. Discloses a means for draining moisture. In addition, the prior art described in Patent Document 3 discloses that dummy cells are provided to prevent flooding at the end of the cell stack.

  However, even when the conventional techniques described in Patent Documents 1 to 3 are used, minute moisture may remain in the reaction gas outlet manifold of the power generation cell of the fuel cell. In particular, in a power generation cell with a small gas flow rate flowing through the reaction gas outlet manifold such as an end cell on the back side of the gas flow path, minute moisture cannot be discharged by the flow of the reaction gas. Becomes stronger. In addition, cells close to the outer surface such as the end cells of the cell stack of the fuel cell are easily affected by the temperature of the outside air, and when the temperature is below freezing, the water staying inside may freeze.

  The cell stack of the fuel cell is configured so that each gas does not leak by sandwiching a gasket for sealing the fuel gas and the oxidant gas between the power generation cells. This gasket is attached around each power generation cell. On the other hand, a membrane electrode assembly that performs a power generation reaction is attached to the center of each power generation cell, and an inlet manifold and an outlet manifold for each reaction gas are formed between the membrane electrode assembly and the gasket.

  When the fuel cell is started, the temperature of the membrane electrode assembly at the center of each power generation cell first rises due to the power generation reaction, and this heat is transferred to gradually increase the temperature at the periphery of each power generation cell. Go. For this reason, at the initial start of the fuel cell, the thickness of the central portion where the membrane electrode assembly is disposed increases in the cell stacking direction due to the temperature rise. On the other hand, since the temperature rise is delayed in the peripheral portion, a difference in thickness occurs in the cell stacking direction due to the temperature difference. This difference in thickness ensures a gas seal due to the repulsive force of the above-described gasket, and thus gas is not leaked from the fuel cell even if a temperature difference occurs in the fuel cell.

  However, if minute moisture remains in the reaction gas outlet manifold provided in the power generation cell provided on the back side of the gas flow such as the end cell or the power generation cell with a low flow rate of the reaction gas, and this freezes, Since the gasket in the frozen portion cannot absorb the difference in thickness in the power generation cell stacking direction due to the temperature generated in the fuel cell, the amount of thermal expansion absorbed in the gasket in the other portion increases. And when it became a state which cannot absorb the thermal expansion by the gasket of another part, there existed a problem that the oxidant gas and fuel gas in a fuel cell might leak from the peripheral part of a cell.

  The above problem occurs in a reaction gas outlet manifold having a small reaction gas flow rate, such as an end portion of a cell stack of a fuel cell. Patent Documents 1 to 3 disclose and suggest such a problem. It does not disclose or suggest means for solving the problem.

  An object of the present invention is to suppress freezing of moisture inside a manifold of a cell stack.

  A fuel cell according to the present invention includes a power generation cell including a membrane electrode assembly, a reaction gas channel through which a reaction gas supplied to the membrane electrode assembly flows, and an outlet manifold connected to the reaction gas channel, and a reaction gas channel And a non-power generation cell including an outlet manifold connected to the reaction gas flow path, and a fuel cell stack including the outlet manifolds, the outlet flow of the power generation cell contacting the outlet manifold The bottom surface of the path is above the bottom surface of the outlet manifold in the gravitational direction, and the bottom surface of the outlet channel in contact with the outlet manifold of the non-power generation cell is at the same position or below the bottom surface of the outlet manifold in the gravity direction. It is on the side. In addition, the inner surface of the outlet channel of the non-power generation cell is preferably subjected to a hydrophilic treatment, and the non-power generation cell includes an end in the stacking direction of the cell stack or a stacking direction. It is also suitable to be provided in the middle.

  The present invention provides an effect that moisture freezing inside the manifold of the cell stack can be suppressed.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a side surface of the fuel cell of the present embodiment. The fuel cell of the present embodiment uses hydrogen as a reaction gas on the fuel side and air as a reaction gas on the oxidant side. As shown in FIG. 1, the fuel cell 11 includes a fuel side electrode having a catalyst layer and a fuel side diffusion layer on both sides of an electrolyte made of a polymer ion exchange membrane, and an oxidation having a catalyst layer and an oxidant side diffusion layer. A plurality of power generation cells 13 configured by sandwiching both sides of a membrane electrode assembly (MEA) configured to be disposed so as to be opposed to the agent side electrode are stacked to obtain a predetermined voltage. The cell stack 14, the air-side dummy cell 26 and the hydrogen-side dummy cell 28 without the membrane electrode assembly stacked on both sides of the cell stack 14, and the generated power stacked on both sides of each dummy cell 26, 28 are taken out. Current-carrying plates 15, 16 and insulating plates 17, 18 laminated on both sides of the current-collecting plate, air-side fastening plate 19 laminated on the air electrode side, and hydrogen-side fastening plate 20 laminated on the hydrogen electrode side, Together It is constructed by sintering.

  Each power generation cell 13 and each dummy cell 26, 28 are provided with an air inlet manifold 30 and an air outlet manifold 32 that pass through the cells 13, 26, 28, respectively. The air-side current collecting plate 15 and the insulating plate 17 are also provided with an air inlet hole 30a and an air outlet hole 32a having the same shape as the air inlet manifold 30 and the air outlet manifold 32 of each power generation cell 13. The manifolds 30 and 32 of each power generation cell 13 are arranged in substantially the same size and at the same height, and the air supply path 29 and air extending through the power generation cell 13 in the stacking direction by stacking the power generation cells 13. A discharge path 31 is configured. The air supply path 29 communicates with the air introduction holes 30a provided in the current collecting plate 15 and the insulating plate 17 and the air inlet holes 25 provided in the air side fastening plate 19, and the air discharge path 31 is provided with current collection. The air outlet holes 32 a provided in the plate 15 and the insulating plate 17 communicate with 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 manifold 30 side is the lower side in the gravity direction, and the side with the air outlet manifold 32 is the upper side in the gravity direction.

  In addition, each of the power generation cells, each manifold, the introduction / extraction hole, and the inlet / outlet hole are provided on the hydrogen side in the same configuration as the air side. These are not shown in FIG. Each power generation cell 13 and each dummy cell 26, 28 are provided with a hydrogen inlet manifold and a hydrogen outlet manifold, respectively. The hydrogen-side current collecting plate 16 and the insulating plate 18 are also provided with hydrogen inlet holes and hydrogen outlet holes having the same shape as the hydrogen inlet manifold and hydrogen outlet manifold of each power generation cell 13. The manifolds of the respective power generation cells 13 are arranged at substantially the same size and at the same height, and have a hydrogen supply path and a hydrogen discharge path extending through the power generation cells 13 in the stacking direction by stacking the power generation cells 13. Constitute. The hydrogen supply path communicates with each hydrogen introduction hole provided in the current collector plate 16 and the insulating plate 18 and the hydrogen inlet hole provided in the hydrogen side fastening plate 20, and the hydrogen discharge path communicates with the current collector plate 16 and the insulation plate. Each hydrogen outlet hole provided in the plate 18 communicates with a hydrogen outlet hole provided in the hydrogen side fastening plate 20. A hydrogen inlet pipe 22 communicating with the hydrogen inlet hole and a hydrogen outlet pipe 24 communicating with the hydrogen outlet hole are provided on the end face of the hydrogen side fastening plate 20.

  The configuration of each power generation cell 13, air side dummy cell 26, and hydrogen side dummy cell 28 of the fuel cell 11 will be described in detail with reference to FIG. 2. In each power generation cell 13, a membrane electrode assembly 13c is sandwiched between a hydrogen side separator 13a and an air side separator 13b. A hydrogen channel 33 through which hydrogen gas flows is formed on the surface of the hydrogen side separator 13a on the membrane electrode assembly side, and a cooling water channel 35 through which cooling water flows is formed on the opposite surface. An air flow path 34 through which air flows is formed on the surface of the air-side separator 13b on the membrane electrode assembly side, and a cooling water flow path 35 through which cooling water flows is formed on the opposite surface. The hydrogen-side separator 13a and the air-side separator 13b are provided with a gasket 60 at the periphery thereof, and a surface pressure is applied to the gasket 60 by the fastening force between the hydrogen-side fastening plate 20 and the air-side fastening plate 19, and each separator. Sealing of gas and cooling water between 13a and 13b is performed. Further, the surfaces of the air side separator 13b and the hydrogen side separator 13a opposite to the membrane electrode assembly 13c are in close contact with each other to form a cooling water passage 35 therebetween. A gasket 60 is also provided on the periphery of the surface of the air side separator 13b and the hydrogen side separator 13a opposite to the membrane electrode assembly 13c. By applying a surface pressure to the gasket 60, cooling water, air, hydrogen gas To prevent leakage. Since the crests of the hydrogen-side separator 13a and the air-side separator 13b that are in contact with the membrane electrode assembly 13c have a function of conducting electricity generated by the membrane electrode assembly 13c, each separator 13a, 13b is made of stainless steel, It is made of a conductive material such as titanium, aluminum or carbon.

  The air introduced from the air inlet pipe 21 of the air side fastening plate 19 of the fuel cell 11 is supplied to the air flow path 34 from the air inlet manifold 30 provided in the air side separator 13 b through the air supply path 29. This air is supplied to the membrane electrode assembly 13c by the air flow path 34 to cause a power generation reaction. The water generated by the power generation reaction and excess air are configured to be discharged from the air flow path 34 to the air outlet manifold 32. The water and excess air discharged to the air outlet manifold 32 are guided to the air outlet hole 27 along the air discharge path 31 and discharged from the air outlet pipe 23 of the air side fastening plate 19 to the outside of the fuel cell. .

  Hydrogen introduced from the hydrogen inlet pipe 22 of the hydrogen side fastening plate 20 of the fuel cell 11 is supplied to the hydrogen flow path 33 from a hydrogen inlet manifold provided in the hydrogen side separator 13a through the hydrogen supply path. This hydrogen is supplied to the membrane electrode assembly 13c through the hydrogen flow path 33 to cause a power generation reaction. The surplus hydrogen is configured to be discharged from the hydrogen flow path 33 to the hydrogen outlet manifold, and the surplus hydrogen discharged from the hydrogen outlet manifold is guided to the hydrogen outlet hole along the hydrogen discharge path, and the hydrogen outlet of the hydrogen side fastening plate 20 It is discharged from the tube 24 to the outside of the fuel cell.

  An air side dummy cell 26 is stacked from the air side fastening plate 19 having the air inlet pipe 21 and the air outlet pipe 23 to the farthest side in the cell stacking direction, that is, the upstream end of the air flow in the air discharge path 31. ing. The air side dummy cell 26 is configured by closely contacting a current collector plate side separator 26a provided on the current collector plate 16 side and a cell side separator 26b provided on the power generation cell 13 side, and the periphery of each separator 26a, 26b. The part is provided with a gasket 60 and is configured to seal air, hydrogen, and cooling water. A cooling water flow path 35 is formed on the current collecting plate 16 side surface of the current collecting plate side separator 26a. An air flow path 37 is formed on the current collecting plate 16 side of the cell side separator 26b, and a cooling water flow path 35 is provided on the power generation cell 13 side. The air flow path 37 is connected to the air inlet manifold 30 and the air outlet manifold 32, and is configured to discharge air supplied from the air supply path 29 to the air discharge path 31. Since the air side dummy cell 26 does not have the membrane electrode assembly 13c between the separators 26a and 26b, it is a non-power generation cell that does not contribute to power generation.

  A hydrogen-side dummy cell 28 is stacked from the hydrogen-side fastening plate 20 having the hydrogen inlet pipe 22 and the hydrogen outlet pipe 24 to the innermost side in the cell stacking direction, that is, the upstream end of the hydrogen flow in the hydrogen discharge path. Yes. The hydrogen side dummy cell 28 is configured by closely contacting a current collector plate side separator 28a provided on the current collector plate 15 side and a cell side separator 28b provided on the power generation cell 13 side, and the periphery of each separator 28a, 28b. The part is provided with a gasket 60 and is configured to seal air, hydrogen, and cooling water. A cooling water flow path 35 is formed on the current collecting plate 15 side surface of the current collecting plate side separator 28a. A hydrogen channel 36 is formed on the current collector 15 side of the cell side separator 28b, and a cooling water channel 35 is provided on the power generation cell 13 side. The hydrogen flow path 36 is connected to the hydrogen inlet manifold and the hydrogen outlet manifold, and is configured to discharge the hydrogen supplied from the hydrogen supply path to the hydrogen discharge path. Since the hydrogen-side dummy cell 28 does not have the membrane electrode assembly 13c between the separators 28a and 28b, it is a non-power generation cell that does not contribute to power generation.

  When the dummy cells 26 and 28 are disposed between the current collecting plates 15 and 16 as shown in FIG. 2, the electricity generated by the membrane electrode assemblies 13c is conducted to the current collecting plates 15 and 16. As in the case of each separator of the power generation cell 13, it is made of a conductive material such as stainless steel, titanium, aluminum, or carbon. However, the dummy cells 26 and 28 are arranged outside the current collector plates 15 and 16. In this case, an insulating material such as a resin may be used.

  FIG. 3A shows the air flow path surface of the air-side separator 13b of the power generation cell. The arrows in the figure indicate the air flow. An air inlet manifold 30 that forms an air supply passage 29 and an air outlet manifold 32 that forms an air discharge passage 31 are disposed around the air-side separator 13b. And the air flow path 34 comprised by many bending flow paths is formed in the center part surface of the air side separator 13b. Further, in the periphery, a hydrogen inlet manifold 40 that forms a hydrogen supply path, a hydrogen outlet manifold 42 that forms a hydrogen discharge path, a cooling water inlet manifold 50 that forms a cooling water supply path, and a cooling that forms a cooling water discharge path. A water outlet manifold 52 is disposed.

  FIG. 3B shows an enlarged portion of the outlet channel 34a that contacts the air outlet manifold 32 of the air channel 34 of the air-side separator 13b of the power generation cell. As shown in FIG. 3B, the bottom surface of the outlet flow path 34 a in contact with the air outlet manifold 32 is formed to be above the bottom surface 38 of the air outlet manifold 32 in the direction of gravity. The water generated in the air flow path 34 by the power generation reaction flows along the air flow through the air flow path 34 toward the outlet flow path 34a. Then, the water flows downward from the outlet flow path 34 a toward the air outlet manifold 32 in the gravity direction, and flows into the bottom surface 38 of the air outlet manifold 32. Then, the fuel is discharged to the outside of the fuel cell 11 along the air discharge passage 31 formed through the air outlet manifold 32. As described above, the water generated inside the air flow path 34 flows downward toward the bottom surface 38 of the air outlet manifold 32, and thus the air flow path of the water generated in the air flow path 34. The obstruction of the flow from 34 to the air outlet manifold 32 is suppressed. For this reason, flooding inside the air flow path 34 and the flow of air being inhibited are suppressed.

  FIG. 4A shows an air flow path 37 formed in the cell side separator 26 b of the air side dummy cell 26. FIG. 4B shows an enlarged portion of the outlet channel 37a that contacts the air outlet manifold 32 of the air channel 37 of the cell-side separator 26b. The arrows in the figure indicate the air flow. Although the basic flow path configuration is the same as that of the air-side separator 13b, the bottom surface of the outlet flow path 37a in contact with the air outlet manifold 32 is more than the bottom surface 38 of the air outlet manifold 32, as shown in FIG. It is formed to be on the lower side in the direction of gravity. Since the air-side dummy cell 26 is a non-power generation cell that does not generate a power generation reaction, water is not generated in the air flow path 37 by the power generation reaction, and the air flowing from the air inlet manifold 30 is directly discharged from the air outlet manifold 32. Is done. The air discharged to the air outlet manifold 32 carries the water discharged to the air outlet manifold 32 of the air side separator 13b onto the flow and pushes it to the outlet side. Moreover, since the inner surface of the outlet channel 37a has been subjected to a hydrophilic treatment, water on the inner surface is easily discharged.

  As described above, during operation of the fuel cell 11 of the present embodiment, water in the flow path is discharged from the outlet manifold 32 toward the air discharge path 31 by the air flowing through the air flow paths 34 and 37. However, the air flow rate inside the air supply path 29 and the air discharge path 31 is larger toward the side closer to the air-side fastening plate 19, and the further from the air-side fastening plate 19 toward the stacking direction, that is, the air discharge path 31. As the air flows upstream, the flow rate decreases, and the force that pushes water becomes weaker. For this reason, in the cell on the back side, that is, the upstream side of the air flow in the air discharge path 31, the water inside the air discharge path 31 cannot be completely discharged to the outside of the fuel cell 11. Minute water stays on the bottom surface of the air outlet manifold 32 or the bottom surface 38 of the air outlet manifold 32.

  FIG. 5 is a cross-sectional view showing the periphery of the air-side dummy cell 26 in the air discharge path 31 of the fuel cell 11. 1 to 4 are denoted by the same reference numerals and description thereof is omitted. As shown in FIG. 5, when the operation of the fuel cell 11 is stopped and the air flow ceases, the minute staying water is transferred from the bottom surface 38 of the air outlet manifold 32 to the air side dummy cell 26 that is on the lower side in the gravity direction. The air channel 37 tends to flow in the reverse direction toward the bottom surface of the outlet channel 37a. Since the inner surface of the outlet channel 37a is hydrophilized, water enters the air channel 37 from the outlet channel 37a even in a small flow force and enters the air channel 37 of the air side dummy cell 26. It will be stored. Thereby, it is possible to suppress water from staying at the bottom of the air discharge path 31, and even in the case where the outside air temperature is lowered, inside the air discharge path 31 of the cell stack 14 or the bottom surface 38 of the air outlet manifold 32. There is an effect that moisture freezing can be suppressed.

  Even if the outside air temperature decreases and the temperature of the fuel cell 11 becomes below freezing point and the accumulated water that has entered the air flow path 37 of the air side dummy cell 26 freezes, the membrane electrode assembly 13c is formed in the air side dummy cell 26. Since it is not provided, the power generation performance is not reduced by freezing. Further, even if the air flow path 37 of the air side dummy cell 26 is blocked due to freezing, the amount of air supplied to the membrane electrode assembly 13c is not reduced and the power generation performance is not lowered. Furthermore, since the portion where freezing occurs is closer to the center of the fuel cell 11 than to the air discharge path 31, there is an effect that the thawing temperature can be reached quickly by the temperature rise of the membrane electrode assembly 13c due to the power generation reaction.

  In the embodiment of the present invention described above, the bottom surface of the outlet channel 37a of the air channel 37 provided in the cell side separator 26b of the air side dummy cell 26 is lower in the gravity direction than the bottom surface 38 of the air outlet manifold 32. However, it may be configured at the same position instead of the lower side in the gravity direction. Also, the bottom surface of the outlet channel of the hydrogen channel 36 provided in the cell side separator 28b of the hydrogen side dummy cell 28 may be lower in the gravity direction than the bottom surface of the hydrogen outlet manifold 42 or at the same position. Alternatively, the air and hydrogen outlet channels of the dummy cells on both the air side and the hydrogen side may be configured to be lower than the outlet manifolds 32 and 42 in the gravity direction or at the same position. In the present embodiment, the inner surface of the outlet channel 37 a has been described as being hydrophilized, but the entire inner surface of the air channel 37 may be hydrophilized.

  In the present embodiment, the cell-side separator 26 b of the air-side dummy cell 26 is provided with an air flow path 37 that connects the air inlet manifold 30 and the air outlet manifold 32, and minute accumulated water is stored in the air flow path 37. As described above, the air flow path 37 is not a flow path connecting the air inlet manifold 30 and the air outlet manifold 32 but can be connected to the air outlet manifold 32 as long as the above-described minute accumulated water can be stored therein. It may be of a chamber shape.

  In the present embodiment, the dummy cell is described as being provided at the end of the cell stack 14 in which the air-side dummy cell 26 and the hydrogen-side dummy cell 28 are stacked with the power generation cell 13, but these dummy cells are not limited to the end. Alternatively, the cell stack 14 may be stacked in the middle. Further, the dummy cells are not limited to two places on both sides, and it is also preferable to provide two or more places in a place where a small amount of moisture is likely to stay and the flow rate of the reaction gas is small.

It is a figure which shows the side surface of the fuel cell in embodiment which concerns on this invention. It is a figure which shows the side cross section of the fuel cell in embodiment which concerns on this invention. It is explanatory drawing which shows the air flow path and air outlet manifold of the air side separator in embodiment which concerns on this invention. It is explanatory drawing which shows the air flow path and air outlet manifold of the cell side separator of the air side dummy cell of the fuel cell in embodiment which concerns on this invention. It is an enlarged view which shows the cross section around the air exhaust path and air outlet manifold of the fuel cell in embodiment which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Fuel cell, 13 Power generation cell, 13a Hydrogen side separator, 13b Air side separator, 13c Membrane electrode assembly, 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 Air side dummy cell, 26a Current collector side separator, 26b Cell side separator, 27 Air outlet hole, 28 Hydrogen side dummy cell, 28a Current collector side separator, 28b Cell side separator, 29 Air supply path, 30 Air inlet manifold, 30a Air inlet hole, 31 Air outlet path, 32 Air outlet manifold, 32a Air outlet hole, 33, 36 Hydrogen flow path, 34, 37 Air flow path, 34a, 37a Outlet flow path, 35 Cooling water flow Channel, 38 Bottom, 40 Hydrogen inlet manifold, 42 Hydrogen outlet manifold, 50 Cooling water inlet manifold, 52 Cooling water outlet manifold, 60 Gasket.

Claims (3)

A power generation cell including a membrane electrode assembly, a reaction gas flow path for flowing a reaction gas supplied to the membrane electrode assembly, and an outlet manifold connected to the reaction gas flow path; and a reaction gas flow path and the reaction gas flow path In a fuel cell including a cell stack in which each outlet manifold passes through a non-power generation cell including a connected outlet manifold,
The bottom surface of the outlet channel in contact with the outlet manifold of the power generation cell is above the bottom surface of the outlet manifold in the direction of gravity,
The bottom surface of the outlet channel in contact with the outlet manifold of the non-power generation cell is at the same position or lower side in the direction of gravity than the bottom surface of the outlet manifold;
A fuel cell. The fuel cell according to claim 1, wherein
The fuel cell, wherein an inner surface of the outlet channel of the non-power generation cell is subjected to a hydrophilic treatment. The fuel cell according to claim 1 or 2,
The non-power generation cell is provided at an end of the cell stack in the stacking direction or in the middle of the stacking direction.

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