JP2009187701A - Fuel cell system, and method of sealing oxidant electrode thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of airtight sealing of a cathode of the fuel cell body while suppressing increase of the number of parts and increase of a parts mounting volume. <P>SOLUTION: A water permeation type humidifier 11 carries out humidification by moving moisture in exhaust air exhausted from an exhaust air outlet 3 of the fuel cell main body 1 to air to be supplied to an air inlet 5. A first open-close valve 47 is opened and closed between an air exhaust port 37 of the water permeation type humidifier 11 and the air inlet 5 of the fuel cell main body 1. A second open-close valve 49 is opened and closed between the exhaust air exit 3 of the fuel cell main body 1 and an exhaust air supply port 31 of the water permeation type humidifier 11. The first open-close valve 47 and the second open-close valve 49 are fixed to a coaxial driving shaft 43. By means that one driving motor 45 rotates the driving shaft 43, the first open-close valve 47 and the second open-close valve 49 are opened and closed simultaneously. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cell system provided with an on-off valve capable of sealing an oxidation electrode of a fuel cell main body, and an oxidant electrode sealing method thereof.

2. Description of the Related Art There is known a fuel cell power generator in which a fuel gas containing hydrogen is sealed in an oxidant electrode and a fuel electrode in order to prevent deterioration due to oxidation of an electrode catalyst of the fuel cell when the polymer electrolyte fuel cell system is stopped. (For example, patent document 1).
Japanese Patent Laying-Open No. 2005-71949 (page 9, FIG. 2)

  However, if an attempt is made to enclose the fuel gas as described in Patent Document 1 in a fuel cell system that does not consider enclosing the fuel gas in the oxidant electrode, the oxidant electrode of the fuel cell body is sealed. It is necessary to provide an open / close valve (shutoff valve). For this reason, there are problems that the number of components increases and a space volume for mounting components is required.

  In order to solve the above-described problems, the present invention provides a fuel cell body including a fuel electrode supplied with fuel gas and an oxidant electrode supplied with oxidant gas, and an exhaust oxidant discharged from the oxidant electrode. A water permeable humidifier that moves and humidifies the moisture in the gas to an oxidant gas that supplies the oxidant electrode, a first on-off valve that opens and closes the passage of the oxidant gas, and a drive that is coaxial with the first on-off valve A second on-off valve that is driven by a shaft to open and close the passage of the exhaust oxidant gas; and a single motor that drives the drive shaft to simultaneously open and close the first on-off valve and the second on-off valve. A fuel cell system as a gist.

  According to the present invention, the first on-off valve for opening and closing the passage of the oxidant gas supplied to the fuel cell main body and the second on-off valve for opening and closing the passage of the exhaust oxidant gas discharged from the fuel cell main body are combined into one. It can be driven by a motor, and an increase in the number of components for sealing the oxidant electrode of the fuel cell body can be suppressed, and the space volume for component mounting can be reduced and the size can be reduced. .

  Next, the fuel cell system of the present invention will be described in detail with reference to the drawings. Although not particularly limited, the fuel cell system described below is a fuel cell system suitable for a vehicle power source.

  FIG. 1 is a perspective view showing a main configuration of a fuel cell system according to a first embodiment of the present invention. In FIG. 1, the direction in which air (oxidant gas) flows is indicated by white arrows, and the direction in which exhaust air (exhaust oxidant gas) flows is indicated by hatched arrows.

  1, the fuel cell system includes a fuel cell main body 1, a water permeable humidifier 11, an air pressure adjustment valve 13, a muffler 15, an exhaust pipe 17, a first on-off valve 47, and a second on-off valve. 49, a drive shaft 43, and a drive motor 45.

  The fuel cell body 1 is a power generation in which an anode (fuel electrode) supplied with hydrogen as a fuel gas and a cathode (oxidant electrode) supplied with air as an oxidant gas are sandwiched with an electrolyte / electrode catalyst composite interposed therebetween. It has a stack structure in which cells are stacked in multiple stages. The fuel cell main body 1 converts chemical energy into electrical energy by the electrochemical reactions of the following (Chemical Formula 1) and (Chemical Formula 2).

[Anode] H ₂ → 2H ⁺ + 2e ⁻ (Chemical Formula 1)
[Cathode] 2H ⁺ + 2e ^{− + (1/2) O} ₂ ^{→ H} ₂ ^O (Chemical Formula 2)
At the anode, hydrogen dissociates into hydrogen ions and electrons, the hydrogen ions pass through the electrolyte, and the electrons pass through an external circuit to generate power and move to the cathode. At the cathode, oxygen in the supplied air reacts with hydrogen ions and electrons to generate water. Then, due to the reaction of (Chemical Formula 2), oxygen is reduced, and humid exhaust air (exhaust oxidant gas) to which water vapor and minute water droplets are added is exhausted from the cathode.

  As the electrolyte of the fuel cell, for example, a solid polymer electrolyte is used in consideration of high energy density, low cost, light weight, and the like. The solid polymer electrolyte is made of an ion conductive polymer membrane such as a fluororesin ion exchange membrane, and functions as a hydrogen ion conductive electrolyte when saturated with water. For this reason, it is necessary to humidify the air supplied to the fuel cell.

  An exhaust air outlet (exhaust manifold) 3 from which exhaust air is exhausted from the cathode is provided on the left side, and an air inlet (supply manifold) 5 for supplying air to the cathode is provided on the right side of the side surface of the fuel cell body 1. One end portions of pipes 7 and 9 are connected to the exhaust air outlet 3 and the air inlet 5 of the fuel cell main body 1, respectively. The other end of the pipe 7 is connected to the second on-off valve 49, and the other end of the pipe 9 is connected to the first on-off valve 47.

  The valve body of the first on-off valve 47 and the valve body of the second on-off valve 49 are provided with a common valve body 41 in which both are integrated. Inside the valve body 41, a flow path for the first on-off valve 47 and a flow path for the second on-off valve 49 are provided independently, and a valve seat (not shown) is provided below the drive shaft 43, respectively. . Further, the valve body 41 is disposed integrally with the water permeable humidifier 11. Since the first on-off valve 47 opens into the air discharge port 37 and the second on-off valve 49 opens into the exhaust air supply port 31, the flow of the air and exhaust air in the valve body 41, respectively. The size of the direction (y direction in the figure) can be reduced, and the volume for mounting the first on-off valve 47 and the second on-off valve 49 can be reduced.

  The first on-off valve 47 and the second on-off valve 49 are arranged coaxially and are respectively fixed to the drive shaft 43. The drive shaft 43 is rotated by a drive motor 45 to open and close the first on-off valve 47 and the second on-off valve 49 simultaneously. More specifically, the first on-off valve 47 and the second on-off valve 49 rotate in the vertical direction (−z direction) by the rotation of the drive shaft 43 by the drive motor 45 and come into contact with respective valve seats (not shown). It is possible to switch between a state, that is, a valve-closed state, and a state that is rotated substantially horizontally, that is, a valve-open state.

  Accordingly, when the first on-off valve 47 and the second on-off valve 49 are closed, the air inlet (oxidant gas inlet) 5 and the exhaust air outlet (exhaust oxidant gas outlet) 3 of the fuel cell main body 1 are simultaneously sealed. In addition, the cathode of the fuel cell body 1 can be sealed.

  The water permeable humidifier 11 is air that has been pressurized and heated in a humid exhaust air (exhaust oxidant gas) discharged from the exhaust air outlet 3 of the fuel cell main body 1 and an air introduction unit such as a compressor (not shown). This is for humidifying the air supplied to the air inlet 5 of the fuel cell body 1 by exchanging moisture with the (oxidant gas).

  The water permeable humidifier 11 is a hollow fiber membrane type humidifier having a housing 19 and a hollow fiber membrane module 21. For the sake of explanation, FIG. 1 shows a state in which the upper lid of the water permeable humidifier 11 is removed and the hollow fiber membrane module 21 is taken out from the housing 19, but actually, the hollow fiber membrane module 21 is The housing 19 is housed inside, and the housing 19 is closed by an upper cover (not shown).

  A housing 19 of the water permeable humidifier 11 includes an exhaust air supply port 31 through which exhaust air is supplied from the fuel cell main body 1 via the pipe 7 and an exhaust air exhaust port through which exhaust air after being humidified is discharged. 33, an air supply port 35 through which air is supplied by a compressor (not shown), and an air discharge port 37 through which humidified air is discharged.

  The hollow fiber membrane module 21 has an approximately rectangular parallelepiped outer shape, and a large number of moisture-permeable hollow fiber membranes 25 extending in the axial direction of the rectangular tube (y direction in the figure) are arranged inside a rectangular tube case 23. It is a thing. At both ends of each hollow fiber membrane 25, with a hollow opening held, an adhesive or the like is applied to the potting portion 27 that is both openings of the square tube so as to seal the space outside the hollow fiber membrane. It is fixed. As a result, an inner flow path is formed which flows from one potting portion 27 to the other potting portion 27 (in the y direction in the figure) through the hollow fiber membrane 25. Air is supplied to the inner flow path from the air supply port 35, is humidified by the hollow fiber membrane 25, and is discharged from the air discharge port 37.

  A plurality of holes 29 are provided on both side surfaces of the case 23 excluding the potting portion 27 of the hollow fiber membrane module 21. By these holes 29, an outer flow path is formed from one side surface of the case 23 to the other side surface of the case 23 via the outer space of the hollow fiber membrane 25 (in the x direction in the figure). And the air flowing through the inner flow path of the hollow fiber membrane 25 and the exhaust air flowing through the outer flow path are flows perpendicular to the x direction and the y direction.

  The exhaust air supply port 31 of the water permeable humidifier 11 is opened and closed by a second opening / closing valve 49. When the second on-off valve 49 is opened, the humid exhaust air exhausted from the exhaust air outlet 3 of the fuel cell body 1 moves from the y direction to the -y direction, that is, in the hollow fiber membrane module 21. The exhaust air supply port 31 is entered from the direction opposite to the flowing direction. The exhaust air has a flow velocity that decreases in the space inside the exhaust air supply port 31 and the direction of the flow is changed to the x direction. From the hole 29 on one side surface of the hollow fiber membrane module 21 to the outer flow path of the hollow fiber membrane. enter. The exhausted air that has passed through the outer flow path and has been reduced in humidity is discharged from a hole (not shown) on the other side facing the one side and enters the exhausted air discharge port 33.

  Thus, in this embodiment, since the exhaust air is supplied to the exhaust air supply port 31 of the water permeable humidifier 11 from the direction opposite to the direction in which air flows in the hollow fiber membrane module 21, the water permeable humidifier is used. The air discharge port 37 and the exhaust air supply port of the vessel 11 can be disposed adjacent to each other. As a result, the water transmission type humidifier 11 and the first on-off valve 47 and the second on-off valve 49 are common. The integrated valve body 41 can be integrated to reduce the overall size.

  Next, the flow area Sv when the first on-off valve 47 and the second on-off valve 49 are opened and the area of the opening of the hollow fiber membrane module 21 will be examined. Sc (= n × s, n: number of hollow fiber membranes, s: breakage of hollow portion per one) of the cross-sectional area of the hollow portion of the hollow fiber membrane 25 that opens to the potting portion 27 of the hollow fiber membrane module 21 Area) and the total opening area of the holes 29 is Sh.

  In order to sufficiently exhibit the humidity exchange performance of the hollow fiber membrane module 21, the hollow fiber membrane module 21 is determined from the flow area when the first and second on-off valves are opened so that Sv <Sc and SV <Sh. The opening area is set to be large. Thereby, the air and exhaust air which flow into the hollow fiber membrane module 21 can fully exhibit humidity exchange performance, without concentrating locally in the hollow fiber membrane module 21. FIG.

  An air pressure adjustment valve 13 is connected downstream of the exhaust air discharge port 33. The air pressure adjusting valve 13 is a valve that adjusts the air pressure in the cathode by changing the pressure loss of the exhaust air discharged from the cathode. A muffler 15 is provided downstream of the air pressure adjustment valve 13 to reduce the emission sound of exhaust air discharged from the air pressure adjustment valve 13. An exhaust pipe 17 that discharges exhaust air to the outside air is provided downstream of the muffler 15.

  Air is supplied to the air supply port 35 of the water permeable humidifier 11 by a compressor or the like (not shown). The supplied air is humidified from the potting portion 27 on the near side of the hollow fiber membrane module 21 through the inner flow path of the hollow fiber membrane 25 and discharged from the opposite potting portion 27 to the air discharge port 37. A first on-off valve 47 is connected to the air discharge port 37. The air that has passed through the first on-off valve 47 is supplied from the air inlet 5 of the fuel cell body 1 to the cathode via the pipe 9.

  During operation of the fuel cell system, the first on-off valve 47 and the second on-off valve 49 are both open, and air humidified by the water permeable humidifier 11 is supplied to the cathode.

  When the fuel cell system is stopped, hydrogen, which is fuel gas, is supplied from the air supply port 35 through a path (not shown), and the air remaining on the cathode of the fuel cell main body 1 is replaced with hydrogen. When the replacement of the cathode air with hydrogen gas is completed, the first opening / closing valve 47 and the second opening / closing valve 49 are simultaneously closed by driving the drive motor 45 and rotating the drive shaft 43. Thus, when the fuel cell operation is stopped, hydrogen gas is enclosed in the cathode, and deterioration of the cathode catalyst due to oxidation can be prevented. Although not specifically shown, it goes without saying that hydrogen gas can be sealed in the anode while the fuel cell operation is stopped.

  In this embodiment, the air passes through the inner flow path of the hollow fiber membrane 25 and is humidified, and the exhaust air passes through the outer flow path of the hollow fiber membrane 25 to reduce moisture. The flow may be reversed so that exhaust air flows through the inner channel and air flows through the outer channel. In this case, for example, if the same configuration of the housing 19 as in FIG. 1 is used, a hollow fiber membrane module in which the extending direction of the hollow fiber membrane inside the hollow fiber membrane module is converted from the y direction to the x direction is used. .

  In the present embodiment, the drive shafts of the first on-off valve 47 and the second on-off valve 49 are positioned so that they do not engage with the opening of the valve seat. However, such as a well-known butterfly valve or ball valve, It is clear that the present invention can be applied even when a valve of the type is used. That is, the valve shafts of the butterfly valve and the ball valve of the first on-off valve and the second on-off valve are coaxially arranged, and these valve shafts connected by one valve shaft member are driven by one drive motor. Thus, the present invention can be applied.

  According to the present embodiment described above, the first on-off valve that opens and closes between the air (oxidant gas) outlet of the water permeable humidifier and the air (oxidant gas) inlet of the fuel cell main body, and the water permeable type Since the second on-off valve that opens and closes between the exhaust air (exhaust oxidant gas) inlet of the humidifier and the exhaust air (exhaust oxidant gas) outlet of the fuel cell main body is arranged coaxially, one drive shaft and one It can be driven by two motors, and the increase in the number of parts for sealing the oxidant electrode of the fuel cell main body can be suppressed, and the space volume for mounting the parts can be reduced and the size can be reduced. is there.

  Further, according to this embodiment, since the first on-off valve and the second on-off valve are arranged on the water permeable humidifier side, the fuel cell system can be further miniaturized, and the water permeable humidifier and the first and second There exists an effect that the intensity | strength of the fastening part with an on-off valve can be ensured.

  Further, according to this embodiment, since the water permeable humidifier is a hollow fiber membrane module, the second on-off valve can be provided in the space for introducing the exhaust gas into the hollow fiber membrane module, and the fuel cell system There is an effect that can be reduced in size.

  Further, according to the present embodiment, since the flow of the oxidant gas and the exhaust oxidant gas in the hollow fiber membrane module is an orthogonal flow, humidity transfer from the exhaust oxidant gas to the oxidant gas is performed with high efficiency. effective.

  Further, according to the present embodiment, the opening area of the hollow fiber membrane module is made larger than the opening area when the first and second on-off valves are opened, so that the oxidant gas and the exhaust oxidant gas are uniformly distributed to the hollow fiber membrane module. Can flow, and the humidity transfer efficiency can be further improved.

  Further, according to this embodiment, the exhaust oxidant gas is introduced into the supply port from the direction opposite to the direction in which the oxidant gas flows in the hollow fiber membrane module, and the flow direction of the exhaust oxidant gas is converted in the supply port. Since it becomes a cross flow, there exists an effect that the shape of a water permeable humidifier can be optimized.

  Furthermore, according to this embodiment, since the valve bodies of the first on-off valve and the second on-off valve are integrated, there is an effect that the number of parts can be further reduced and the size can be reduced.

  FIG. 2 is a perspective view showing the configuration of the main part of a second embodiment of the fuel cell system according to the present invention. FIG. 2 also shows a state in which the top cover of the water permeable humidifier 11 is removed, as in FIG. 1, but the hollow fiber membrane module itself is the same as in FIG.

  The difference in configuration between the second embodiment and the first embodiment is that the shape of the valve body and the shape of the drive motor are different, and the exhaust air outlet 3a and the air inlet 5a of the fuel cell main body 1 are arranged close to each other. The point is that the pipes 7 and 9 used in Example 1 are omitted. Other configurations are the same as those of the first embodiment. When the exhaust air outlet 3a and the air inlet 5a of the fuel cell main body 1 are arranged close to each other, the first on-off valve 47 and the second on-off valve 49 can be directly connected to the fuel cell main body 1 without using piping. .

  In this embodiment, the valve body 41a of the first on-off valve 47 and the valve body 41b of the second on-off valve 49 are separated, and a double-shaft type drive motor 45a is provided between the valve body 41a and the valve body 41b. It is arranged. Then, the fuel cell main body 1 and the water permeable humidifier 11 can be coupled via the valve body 41a and the valve body 41b without using piping.

  Further, a first on-off valve 47 is fixed to the right side of the drive shaft 43 that passes through the drive motor 45a and extends in both the left and right directions, and a second on-off valve 49 is fixed to the left side thereof. The first on-off valve 47 and the second on-off valve 49 can be simultaneously opened and closed by driving the drive shaft 43 by the drive motor 45a, as in the first embodiment.

  According to the second embodiment described above, the first on-off valve that opens and closes between the air (oxidant gas) outlet of the water permeable humidifier and the air (oxidant gas) inlet of the fuel cell body, and the water permeable type Since the second on-off valve that opens and closes between the exhaust air (exhaust oxidant gas) inlet of the humidifier and the exhaust air (exhaust oxidant gas) outlet of the fuel cell main body is arranged coaxially, one drive shaft and one It can be driven by two motors, and the increase in the number of parts for sealing the oxidant electrode of the fuel cell main body can be suppressed, and the space volume for mounting the parts can be reduced and the size can be reduced. is there.

  Further, according to the second embodiment, since the exhaust air outlet 3a and the air inlet 5a of the fuel cell main body 1 are arranged close to each other, the first on-off valve 47 and the second on-off valve 49 are connected to the fuel cell main body. There is an effect that it can be directly connected without being used, and the fuel cell system can be further miniaturized. Further, according to the present embodiment, there is an effect that the mechanical strength of the fuel cell system can be improved.

  FIG. 3 is a perspective view showing the configuration of the main part of a third embodiment of the fuel cell system according to the present invention. FIG. 3 also shows a state in which the upper lid of the water permeable humidifier 11 is removed as in FIG. 1, but the hollow fiber membrane module itself is the same as FIG.

  In the third embodiment, the interval between the exhaust air outlet 3a and the air inlet 5a of the fuel cell body 1 is arranged closer to the interval between the exhaust air outlet 3 and the air inlet 5 of the first embodiment. It is the structure which deleted the piping 7 and 9 used. In this embodiment, a valve assembly 51 using an integrated valve body 41 incorporating a first on-off valve and a second on-off valve is integrated with the fuel cell body 1 and fastened. Other configurations are the same as those of the first embodiment.

  According to the third embodiment described above, in addition to the effects of the first embodiment, the fuel cell system can be further reduced in size and the mechanical strength of the fuel cell system can be improved.

  In the fourth embodiment, a modification of the first and second embodiments will be described. In Example 1 and Example 2, the first on-off valve opens and closes the air outlet of the water permeable humidifier and the air inlet of the fuel cell main body, and the second on-off valve opens the exhaust air inlet of the water permeable humidifier. And the exhaust air outlet of the fuel cell body are opened and closed. However, the first on-off valve is disposed, for example, upstream of the air supply port 35 in FIG. 1, and the second on-off valve is disposed, for example, downstream of the exhaust air discharge port 33 in FIG. In addition, each embodiment can be modified. In this case, since the oxidant electrode (cathode) of the fuel cell main body is sealed in a state including the water permeable humidifier 11, high airtightness of the housing 19 of the water permeable humidifier 11 is required.

  Thus, in the fourth embodiment, which is a modification of the first and second embodiments, the drive shaft that drives the first on-off valve and the drive shaft that drives the second on-off valve are arranged coaxially, as in the first and second embodiments. The first on-off valve and the second on-off valve can be simultaneously opened and closed by driving these drive shafts with a single drive motor.

  According to the fourth embodiment described above, the first on-off valve that opens and closes the air (oxidant gas) outlet of the water permeable humidifier and the air (oxidant gas) inlet of the fuel cell main body, and the water permeable type Since the second on-off valve that opens and closes between the exhaust air (exhaust oxidant gas) inlet of the humidifier and the exhaust air (exhaust oxidant gas) outlet of the fuel cell main body is arranged coaxially, one drive shaft and one It can be driven by two motors, and the increase in the number of parts for sealing the oxidant electrode of the fuel cell main body can be suppressed, and the space volume for mounting the parts can be reduced and the size can be reduced. is there.

It is a perspective view explaining the principal part structure of Example 1 of the fuel cell system which concerns on this invention. It is a perspective view explaining the principal part structure of Example 2 of the fuel cell system which concerns on this invention. It is a perspective view explaining the principal part structure of Example 3 of the fuel cell system which concerns on this invention.

Explanation of symbols

1 Fuel cell body 3 Exhaust air outlet (exhaust oxidant gas outlet)
5 Air inlet (oxidant gas inlet)
7, 9 Piping 11 Water permeation type humidifier 13 Air pressure adjusting valve 15 Muffler 17 Exhaust pipe 19 Housing 21 Hollow fiber membrane module 23 Case 25 Hollow fiber membrane 27 Potting portion 29 Hole 31 Exhaust air supply port 33 Exhaust air discharge port 35 Air supply Port 37 Air discharge port 41 Valve body 43 Drive shaft 45 Drive motor 47 First on-off valve 49 Second on-off valve

Claims (9)

A fuel cell body having a fuel electrode supplied with fuel gas and an oxidant electrode supplied with oxidant gas;
A water permeable humidifier that moves and humidifies the moisture in the exhaust oxidant gas discharged from the oxidant electrode to the oxidant gas that is supplied to the oxidant electrode;
A first on-off valve for opening and closing the oxidant gas passage;
A second on-off valve that is driven by a drive shaft coaxial with the first on-off valve and opens and closes the passage of the exhaust oxidant gas;
One motor for driving the drive shaft to simultaneously open and close the first on-off valve and the second on-off valve;
A fuel cell system comprising: The first on-off valve opens and closes between the oxidant gas outlet of the water permeable humidifier and the oxidant gas inlet of the fuel cell main body,
2. The fuel cell system according to claim 1, wherein the second on-off valve opens and closes between an exhaust oxidant gas inlet of the water permeable humidifier and an exhaust oxidant gas outlet of the fuel cell main body.   The first on-off valve is provided on the oxidant gas outlet side of the water permeable humidifier, and the second on-off valve is provided on the exhaust oxidant gas inlet side of the water permeable humidifier, respectively. The fuel cell system described in 1. The water permeable humidifier comprises a hollow fiber membrane module having a hollow fiber membrane that moves moisture inside and outside the membrane, and a space for introducing gas before supplying the exhaust oxidant gas to the hollow fiber membrane module. With
The fuel cell system according to claim 3, wherein a second opening / closing valve is provided in the space.   Inside the water permeable humidifier, the flow of the oxidant gas and the exhaust oxidant gas is a cross flow, and the area of the opening of the hollow fiber membrane module is the opening of the first and second on-off valves. The fuel cell system according to claim 4, wherein the fuel cell system is larger than a passage area at the time. A supply port for introducing the exhaust oxidant gas into the hollow fiber membrane module;
The exhaust oxidant gas is introduced into the supply port from a direction opposite to the direction in which the oxidant gas flows in the hollow fiber membrane module, and the flow direction of the exhaust oxidant gas is converted in the supply port. The fuel cell system according to claim 5.   The fuel cell system according to any one of claims 2 to 6, wherein a valve body in which the valve body of the first on-off valve and the valve body of the second on-off valve are integrated is used. An oxidant gas inlet for supplying the oxidant gas humidified from the water permeable humidifier to the fuel cell main body and a waste oxidant gas outlet for discharging the exhaust oxidant gas from the fuel cell main body are disposed adjacent to each other,
The fuel according to claim 7, wherein the water permeable humidifier, the valve assembly using the integrated valve body, and the fuel cell main body are integrated without using a pipe. Battery system.   A first on-off valve that opens and closes an oxidant gas supply passage for supplying an oxidant gas to the oxidant electrode of the fuel cell main body, and is disposed coaxially with the first on-off valve to discharge exhaust oxidant gas from the oxidant electrode A method for sealing an oxidant electrode of a fuel cell system, wherein a second on-off valve that opens and closes a waste oxidant gas discharge passage is simultaneously opened and closed by a single motor.

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