JP2006344460A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system wherein unreacted gas is humidified by using water vapor of existing reactive gas without increasing the number of components. <P>SOLUTION: This fuel cell system 1 is provided with a solid polymer membrane 200 wherein a cathode electrode 207 and an anode electrode 270 are formed and a first separator 100 and a second separator 300 clamping the solid polymer membrane 200. In the first separator 100, an non-reaction passage 103a through which the unreacted gas flows and a reaction passage 103b guiding the gas flowing through the non-reaction passage 103a to the electrode 207 are formed. In the second separator 300, a passage 350 intersecting with the non-reaction passage 103a of the first separator 100 with the solid polymer membrane 200 in between and flowing existing reactive gas therein is formed. The water contained in the existing reactive gas flowing through the passage 350 penetrates the solid polymer membrane 200 to humidify the unreacted gas flowing through the non-reaction passage 103a of the first separator 100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell system.

  A polymer electrolyte fuel cell is configured by laminating a single cell composed of a membrane electrode assembly (hereinafter referred to as “MEA”) and a separator. The MEA has an anode electrode (anode gas electrode; hydrogen electrode) formed on one surface of the electrolyte membrane and a cathode electrode (cathode gas electrode; oxygen electrode) formed on the other surface.

In the anode electrode, an anode gas containing hydrogen H ₂ is supplied from the separator and reacts as follows.
Anode electrode: 2H ₂ → 4H ⁺ + 4e ⁻ .

The proton H ⁺ thus generated at the anode electrode passes through the electrolyte membrane and reaches the cathode electrode. Further, the electron e ⁻ reaches the cathode electrode through an external circuit.

In the cathode electrode, a cathode gas containing oxygen O ₂ is supplied from the separator. This cathode gas reacts with protons H ⁺ and electrons e ⁻ reaching the cathode electrode as follows.
Cathode electrode: O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O.

In this process, it is indispensable for the operation of a polymer electrolyte fuel cell (hereinafter referred to as “fuel cell”) to maintain an appropriate conductivity of proton H ⁺ that permeates the electrolyte membrane.

Since the conductivity of proton H ⁺ is proportional to the amount of water, it is necessary to keep the moisture content of the electrolyte membrane moderate during the operation of the fuel cell. However, during operation of the fuel cell, the electrolyte membrane is dried by the supplied anode gas and cathode gas (hereinafter referred to as “unreacted gas”) that have not yet reacted. Therefore, normally, the unreacted gas is humidified in advance, and the moisture content of the electrolyte membrane is maintained by this moisture.

  Here, if the water for humidifying the unreacted gas is stored outside, the fuel cell system becomes larger correspondingly. Therefore, the anode gas and the cathode gas that have already reacted through the anode electrode and the cathode electrode (hereinafter referred to as “reacted gas”) take advantage of the characteristics of the fuel cell that contain more water vapor than the unreacted gas. The method is used. In this method, since the water vapor of the already reacted gas is added to the unreacted gas, it is not necessary to prepare water for humidification outside the fuel cell in advance, and the fuel cell system can be downsized.

Therefore, in Patent Document 1, a fuel cell system provided with a wet temperature exchanging means configured to contact an already reacted gas and an unreacted gas through a temperature / humidity exchange membrane and add water vapor of the already reacted gas to the unreacted gas. Is provided.
Japanese Patent Laid-Open No. 2003-31246

  However, the conventional fuel cell system has a problem that the number of parts is still large because a plate for separating the unreacted gas and the already reacted gas or a wet temperature exchange membrane is used in addition to the separator used for the fuel cell. .

  The present invention has been made paying attention to such a conventional problem, and an object of the present invention is to provide a fuel cell system capable of adding the water vapor of the already reacted gas to the unreacted gas without newly providing parts. And

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected, it is not limited to this.

  A solid polymer film (200) on which a cathode electrode (207) and an anode electrode (270) are formed, and a first separator (100) and a second separator (300) that sandwich the solid polymer film (200). A fuel cell system (1) comprising: an unreacted passage (103a) through which unreacted gas that has been supplied from a supply manifold (101) and has not yet reacted flows to the first separator (100); A reaction passage (103b) for guiding the gas flowing through the passage (103a) to the electrode (207) is formed, and the first separator is sandwiched between the second polymer separator (300) and the solid polymer membrane (200). A passage (350) that intersects the unreacted passage (103a) of (100) and flows through the reaction passage (103b) and through which the reacted gas containing reaction water flows The water contained in the already-reacted gas flowing through the passage (350) formed in the second separator (300) permeates the solid polymer membrane (200) to form the first separator (100). The unreacted gas flowing through the unreacted passage (103a) is humidified.

  According to the present invention, the already-reacted gas and the unreacted gas are separated using the separator sandwiching the solid polymer membrane, and the water vapor of the already-reacted gas is added to the unreacted gas using the solid polymer membrane. Accordingly, it is possible to provide a fuel cell system that can humidify the unreacted gas using the water vapor of the already reacted gas without newly using a humidifying membrane or a separator for separating the gas.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing a single cell 1 used in the first embodiment of the fuel cell system of the present invention. FIG. 1A is a diagram showing a laminated cross section of the single cell 1. FIG. 1B is an enlarged view of the region b in FIG. 1A and is a view showing a cross section of the water vapor permeable portions 221 and 222 of the electrolyte membrane 200. In order to facilitate understanding of the present invention, the single cells 1 adjacent to both sides are also shown.

  The single cell 1 includes a cathode separator 100, an electrolyte membrane 200, and an anode separator 300.

  The electrolyte membrane 200 is sandwiched between the cathode separator 100 and the anode separator 300. As shown in FIG. 1B, the electrolyte membrane 200 is sandwiched between porous bodies 200b in water vapor permeable portions 221 and 222 described below. A gas diffusion layer is used for the porous body 200b. The electrolyte membrane 200 has a cathode electrode 207 near the center of one surface, and an anode electrode 270 on the back surface of the cathode electrode 207. The cathode electrode 207 includes a cathode catalyst layer and a gas diffusion layer. The anode electrode 270 includes an anode catalyst layer and a gas diffusion layer.

  In the single cell 1 configured as described above, the cathode gas contacts the cathode electrode 207 while flowing through the cathode separator 100. The anode gas contacts the anode electrode 270 while flowing through the anode separator 300. In this way, the single cell 1 generates power by bringing the cathode gas and the anode gas into contact with the respective electrodes.

  Next, details of the cathode separator 100, the electrolyte membrane 200, and the anode separator 300 will be described with reference to FIG.

  FIG. 2 is a diagram showing each component of the single cell 1 used in the first embodiment of the fuel cell system of the present invention. FIG. 2A is a view of the cathode separator 100 as viewed from the electrolyte membrane 200 side. FIG. 2B is a view of the electrolyte membrane 200 as viewed from the anode separator 300 side. FIG. 2C is a view seen through the anode separator 300 from the side opposite to the electrolyte membrane 200 side. 2 (A) to 2 (C), the thick line is a line indicating a sealing material for preventing leakage of anode gas and cathode gas.

  The cathode separator 100, the electrolyte membrane 200, and the anode separator 300 each have the same rectangular shape.

  The cathode separator 100 contacts the cathode electrode 207 near the center. This abutting area is shown as a cathode abutting area C in the figure. The cathode contact area C is rectangular.

  The cathode separator 100 includes a cathode gas supply manifold 101, a flow path 103, a recess 104, a cathode gas discharge manifold 106, an anode gas supply manifold 110, a recess 140, a straight flow path 150, and an anode gas discharge manifold. 160 is formed.

  The cathode gas supply manifold 101 is formed outside the cathode contact region C and near the center of the short side of the cathode separator 100 (the right end in FIG. 2A). The cathode gas supply manifold 101 is formed so as to penetrate the cathode separator 100.

  The recess 104 is formed between the cathode gas supply manifold 101 and the cathode contact region C. The recess 104 is formed by recessing the cathode separator 100.

  The channel 103 is a channel that communicates the cathode gas supply manifold 101 and the recess 104. The channel 103 includes a connection channel 103a, a reaction channel 103b, and a connection channel 103c. The connection flow path 103 a is disposed outside the cathode contact region C and communicates with the cathode gas supply manifold 101. The reaction channel 103b is disposed in the cathode contact region C and contacts the cathode electrode 207. The connection flow path 103 c is disposed outside the cathode contact region C and communicates with the recess 104. Cathode gas supplied from the cathode gas supply manifold 101 sequentially flows through the connection flow path 103a → the reaction flow path 103b → the connection flow path 103c, and the reaction at the cathode electrode described above occurs when flowing through the reaction flow path 103b. Is called. Moreover, the reaction channel 103b of this embodiment is a serpentine channel.

  The cathode gas discharge manifold 106 is formed on the opposite side of the recess 104 with the flow path 103a interposed therebetween. Cathode gas exhaust manifold 106 is formed to penetrate cathode separator 100.

  The anode gas supply manifold 110 is formed outside the cathode contact region C and near the center of the short side of the cathode separator 100 (left end in FIG. 2A). The anode gas supply manifold 110 is formed so as to penetrate the cathode separator 100.

  The recess 140 is formed between the anode gas supply manifold 110 and the cathode contact region C. The recess 140 is formed by recessing the cathode separator 100.

  The straight flow path 150 is a flow path that connects the recess 140 and an anode gas discharge manifold 160 described later.

  The anode gas discharge manifold 160 is formed between the anode gas supply manifold 110 and the cathode contact region C. The anode gas exhaust manifold 160 is formed to penetrate the cathode separator 100.

  In the electrolyte membrane 200, an anode electrode 270 is formed near the center. The anode electrode 270 is rectangular. A cathode electrode 207 is formed on the back side of the anode electrode 270 across the electrolyte membrane 200 (not shown).

  A cathode gas supply manifold 201, a communication hole 204, a cathode gas discharge manifold 206, an anode gas supply manifold 210, a communication hole 240, and an anode gas discharge manifold 260 are formed in the electrolyte membrane 200.

  The cathode gas supply manifold 201 is formed outside the anode electrode 270 and near the center of the short side of the electrolyte membrane 200 (right end in FIG. 2B). The cathode gas supply manifold 201 is formed so as to penetrate the electrolyte membrane 200. When the electrolyte membrane 200 is overlaid on the cathode separator 100, the cathode gas supply manifold 201 overlaps the cathode gas supply manifold 101.

  The communication hole 204 is formed between the cathode gas supply manifold 201 and the anode electrode 270. When the electrolyte membrane 200 is stacked on the cathode separator 100, the communication hole 204 overlaps with the recess 104.

  Cathode gas exhaust manifold 206 is formed between cathode gas supply manifold 201 and anode electrode 270. The cathode gas exhaust manifold 206 is formed so as to penetrate the electrolyte membrane 200. When the electrolyte membrane 200 is stacked on the cathode separator 100, the cathode gas discharge manifold 206 overlaps the cathode gas discharge manifold 106.

  A portion of the electrolyte membrane 200 between the communication hole 204 and the cathode gas discharge manifold 206 is shown as a water vapor permeation portion 221 in the figure. The water vapor transmission portion 221 contacts the connection flow path 103a.

  The anode gas supply manifold 210 is formed outside the anode electrode 270 and near the center of the short side of the electrolyte membrane 200 (left end in FIG. 2B). The anode gas supply manifold 210 is formed so as to penetrate the electrolyte membrane 200. When the electrolyte membrane 200 is overlaid on the cathode separator 100, the anode gas supply manifold 210 overlaps with the anode gas supply manifold 110.

  The communication hole 240 is formed between the anode gas supply manifold 210 and the anode electrode 270. When the electrolyte membrane 200 is stacked on the cathode separator 100, the communication hole 240 overlaps with the recess 140.

  The anode gas exhaust manifold 260 is formed between the anode gas supply manifold 210 and the anode electrode 270. The anode gas exhaust manifold 260 is formed so as to penetrate the electrolyte membrane 200. When the electrolyte membrane 200 is overlaid on the cathode separator 100, the anode gas discharge manifold 260 overlaps with the anode gas discharge manifold 160.

  A portion of the electrolyte membrane 200 between the communication hole 240 and the anode gas discharge manifold 260 is shown as a water vapor permeation portion 222 in the figure. The water vapor transmission portion 222 is in contact with the straight flow path 150.

  The anode separator 300 contacts the anode electrode 270 near the center. This abutting region is indicated by a square in the figure as an anode abutting region A. The anode contact area A is a rectangle equivalent to the cathode contact area C.

  The anode separator 300 includes an anode gas supply manifold 310, a flow path 303, a recess 340, an anode gas discharge manifold 360, a cathode gas supply manifold 301, a recess 304, a straight flow path 350, and a cathode gas discharge manifold 306. And are formed.

  The anode gas supply manifold 310 is formed outside the anode contact area A and in the vicinity of the center of the short side of the anode separator 300 (right end in FIG. 2C). The anode gas supply manifold 310 is formed so as to penetrate the anode separator 300. When the anode separator 300 is overlaid on the electrolyte membrane 200, the anode gas supply manifold 310 overlaps the anode gas supply manifold 210.

  The recess 340 is formed between the anode gas supply manifold 310 and the anode contact area A. The recess 340 is formed by recessing the anode separator 300. When the anode separator 300 is overlaid on the electrolyte membrane 200, the recess 340 overlaps the communication hole 240.

  The channel 303 is a channel that communicates the anode gas supply manifold 310 and the recess 340. The channel 303 has a connection channel 303a, a reaction channel 303b, and a connection channel 303c. The connection channel 303 a is disposed outside the anode contact region A and communicates with the anode gas supply manifold 310. When the anode separator 300 is stacked on the electrolyte membrane 200, the connection flow path 303 a contacts the water vapor transmission part 222 and intersects the straight flow path 150 with the water vapor transmission part 222 interposed therebetween. The reaction channel 303b is disposed in the anode contact area A and contacts the anode electrode 270. The connection flow path 303 c is disposed outside the anode contact area A and communicates with the recess 340. The anode gas supplied from the anode gas supply manifold 310 sequentially flows through the connection flow path 303a → the reaction flow path 303b → the connection flow path 303c, and the reaction at the anode electrode described above occurs when flowing through the reaction flow path 303b. Is called. Further, the reaction channel 303b of this embodiment is a serpentine channel.

  The anode gas discharge manifold 360 is formed on the opposite side of the recess 340 across the flow path 303a. The anode gas exhaust manifold 360 is formed to penetrate the anode separator 300. When the anode separator 300 is overlaid on the electrolyte membrane 200, the anode gas discharge manifold 360 overlaps with the anode gas discharge manifold 260.

  The cathode gas supply manifold 301 is formed outside the anode contact region A and near the center of the short side of the anode separator 300 (right end in FIG. 2C). The cathode gas supply manifold 301 is formed so as to penetrate the anode separator 300. When the anode separator 300 is stacked on the electrolyte membrane 200, the cathode gas supply manifold 301 overlaps the cathode gas supply manifold 201.

  The recess 304 is formed between the cathode gas supply manifold 301 and the anode contact area A. The recess 304 is formed by recessing the anode separator 300. When the anode separator 300 is stacked on the electrolyte membrane 200, the recess 304 overlaps the communication hole 204.

  The straight flow path 350 is a flow path that connects the recess 304 and an anode gas discharge manifold 306 described later. When the anode separator 300 is stacked on the electrolyte membrane 200, the straight flow path 350 is in contact with the water vapor transmission portion 221 and intersects the connection flow path 103a with the water vapor transmission portion 221 interposed therebetween.

  The cathode gas discharge manifold 306 is formed between the cathode gas supply manifold 301 and the anode contact area A. Cathode gas exhaust manifold 306 is formed to penetrate anode separator 300. When the anode separator 300 is stacked on the electrolyte membrane 200, the cathode gas discharge manifold 306 overlaps with the cathode gas discharge manifold 306.

  The movement of the cathode gas and the anode gas in the single cell 1 will be described with reference to FIGS. First, the movement of the cathode gas will be described.

  The cathode gas is supplied from the outside, flows through the cathode gas supply manifolds 301 and 201, and flows from the cathode gas supply manifold 101 over the cathode separator 100.

The cathode gas flows through the flow path 103 and flows into the recess 104. The cathode gas sequentially flows as described above, and reacts with proton H ⁺ on the cathode electrode 207 when the reaction gas 103b is circulated, and the generated water is added. For this reason, the already reacted cathode gas flowing through the connection flow path 103c contains more water vapor than the unreacted cathode gas flowing through the connection flow path 103a.

  The already-reacted cathode gas flows through the communication hole 204 from the recess 104. Then, the straight channel 350 flows from the recess 304.

  As described above, the straight flow path 350 intersects the connection flow path 103a with the water vapor transmission portion 221 interposed therebetween. For this reason, the already-reacted cathode gas having a high water vapor partial pressure flows through the water vapor transmitting portion 221 to the anode separator 300 side. On the cathode separator 100 side of the water vapor transmission portion 221, unreacted cathode gas having a lower water vapor partial pressure than the already reacted cathode gas flows. In this way, there is a difference in water vapor partial pressure between the cathode gases flowing on both sides of the water vapor permeable portion 221. Therefore, the water vapor transmission part 221 transmits water vapor from the already reacted cathode gas having a high water vapor partial pressure to the unreacted cathode gas having a low water vapor partial pressure. That is, the water vapor contained in the already reacted cathode gas in the straight channel 350 is added to the unreacted cathode gas in the connection channel 103a.

  The already-reacted cathode gas is discharged from the cathode gas discharge manifold 306 through the cathode gas discharge manifolds 206 and 106 to the outside.

  The movement of the anode gas will be described.

  The anode gas is supplied from the outside, flows through the anode gas supply manifolds 110 and 210, and flows from the anode gas supply manifold 310 over the anode separator 300.

  The anode gas flows through the flow path 303 and flows into the recess 340. The anode gas sequentially flows as described above, and water on the anode electrode 270 that has been moved by back diffusion is added when flowing through the reaction channel 303b. From this, the already-reacted anode gas flowing through the connection channel 303c contains more water vapor than the unreacted anode gas flowing through the connection channel 303a.

  The already reacted anode gas flows from the recess 340 through the communication hole 240. Then, the straight channel 150 flows from the recess 140.

  As described above, the straight flow path 150 intersects the connection flow path 303a with the water vapor transmission portion 222 interposed therebetween. For this reason, the already-reacted anode gas having a high water vapor partial pressure flows through the water vapor transmitting portion 222 to the cathode separator 100 side. On the anode separator 300 side of the water vapor transmission portion 222, unreacted anode gas having a lower water vapor partial pressure than the already reacted anode gas flows. In this way, the anode gas flowing on both sides of the water vapor permeable portion 222 has a difference in water vapor partial pressure. Therefore, the water vapor transmission part 222 transmits water vapor from the already reacted anode gas having a high water vapor partial pressure to the unreacted anode gas having a low water vapor partial pressure. That is, the water vapor contained in the already reacted anode gas in the straight channel 150 is added to the unreacted anode gas in the connection channel 303a.

  The already-reacted anode gas is discharged from the anode gas discharge manifold 160 through the anode gas discharge manifolds 260 and 360 to the outside.

  In the single cell 1 used in the fuel cell system of the present embodiment, the straight flow path 350 through which the reacted cathode gas flows and the connection flow path 103a through which the unreacted cathode gas flows cross each other across the water vapor transmission portion 221. It was. Similarly, the straight flow path 150 through which the reacted anode gas flows and the connection flow path 303a through which the unreacted anode gas flow intersect each other with the water vapor transmission portion 222 interposed therebetween. By configuring the single cell 1 in this way, the water vapor of the already reacted gas can be added to the unreacted gas using the water vapor permeable portions 221 and 222 which are part of the electrolyte membrane 200. From this, in the fuel cell system of the present embodiment, it is possible to add the water vapor of the already reacted gas to the unreacted gas without newly using a water vapor permeable membrane.

  In the present embodiment, the connection channel 103a through which unreacted cathode gas flows is formed in the cathode separator 100, and the straight channel 350 through which unreacted cathode gas flows is formed in the anode separator 300. Similarly, a connection flow path 303a through which unreacted anode gas flows is formed in the anode separator 300, and a straight flow path 150 through which pre-reacted anode gas flows is formed in the cathode separator 100.

  In this manner, the reacted gas and the unreacted gas are separated using the cathode separator 100 and the anode separator 300 of the single cell 1. Therefore, in the fuel cell system of the present embodiment, the previously reacted gas and the unreacted gas are separated without newly using a separator, and the water vapor of the already reacted gas can be added to the unreacted gas.

  In the present embodiment, the channel 103 having the serpentine-like reaction channel 103 b is formed in the cathode separator 100. Similarly, a channel 303 having a serpentine-like reaction channel 303b was formed in the anode separator 300. By doing in this way, the already reacted gas can be distribute | circulated in the vicinity of the connection flow paths 103a and 303a which an unreacted gas distribute | circulates.

  Furthermore, in this embodiment, the recessed part 104, the communication hole 204, and the recessed part 304 were formed. Similarly, a recess 340, a communication hole 240, and a recess 140 were formed. By doing in this way, unreacted gas and the already reacted gas cross | circulate and distribute | circulate on both sides of water vapor permeation | transmission area | regions 221 and 222.

  Both sides of the water vapor transmission portions 221 and 222 were sandwiched between the porous bodies 200b. From this, the water vapor transmission portions 221 and 222 are strengthened, and it is possible to cope with a case where a differential pressure is generated in each gas flowing between the cathode separator 100 side and the anode separator 300 side. Further, the water vapor transmission portions 221 and 222 can more quickly transmit water vapor from the straight flow paths 150 and 350 through which the already reacted gas flows to the connection flow paths 103a and 303a through which the unreacted gas flows.

  In this way, the already-reacted gas is circulated in the vicinity of the unreacted gas using each component of the single cell 1. Therefore, in the fuel cell system of the present embodiment, the water vapor of the already reacted cathode gas can be added to the unreacted cathode gas without newly using the piping for transporting the reactant gas.

Therefore, according to the present embodiment, it is possible to provide a fuel cell system capable of adding the water vapor of the already reacted gas to the unreacted gas without newly providing parts.
(Second Embodiment)
FIG. 3 is a diagram showing each component of the single cell 1 used in the second embodiment of the fuel cell system of the present invention. In the following embodiments, the same reference numerals are given to the portions that perform the same functions as those of the above-described embodiments, and redundant descriptions are omitted as appropriate.

  In the first embodiment, the reaction flow paths of the cathode separator 100 and the anode separator 300 are serpentine-shaped flow paths 103b and 303b, respectively, but in this embodiment, the straight flow paths 103b and 303b are used. In the first embodiment, the already-reacted cathode gas flows through the communication hole 204 in the electrolyte membrane 200, but in this embodiment, the cathode gas is disposed outside the electrolyte membrane 200 and flows through the passage formed by the recesses 104 and 304. Similarly, the already-reacted anode gas is different from the first embodiment in that it passes through the passage formed by the recesses 140 and 340.

  The electrolyte membrane 200 is rectangular as in the first embodiment. The cathode separator 100 and the anode separator 300 have the same shape, and have a rectangular portion in contact with the electrolyte membrane 200 and portions formed on the outer sides of the four sides.

  The cathode separator 100 includes a cathode gas supply manifold 101, a straight channel 103, a recess 104, a cathode gas discharge manifold 106, an anode gas supply manifold 110, a recess 140, a straight channel 150, and an anode. A gas exhaust manifold 160 is formed.

  The cathode gas supply manifold 101 and the anode gas supply manifold 110 are respectively arranged outside the short sides of the rectangular portion in contact with the electrolyte membrane 200 (the left end and the right end in FIG. 3A).

  The channel 103 includes a connection channel 103a, a reaction channel 103b, and a connection channel 103c. In the present embodiment, the reaction channel 103b is a straight channel.

  Cathode gas supplied from the cathode gas supply manifold 101 sequentially flows through the connection flow path 103a → the reaction flow path 103b → the connection flow path 103c, and the reaction at the cathode electrode described above occurs when flowing through the reaction flow path 103b. Is called.

  The recess 140 and the recess 104 are formed at one end of the cathode separator 100 (upper side and lower side in FIG. 3A). The concave portion 140 and the concave portion 104 form a passage together with the later-described concave portion 340 and the concave portion 304 when configuring the single cell 1. This passage is disposed outside the long side of the electrolyte membrane 200 described later.

  The left side region of the electrolyte membrane 200 is a water vapor permeable portion 221 and is indicated by dots in the drawing. The water vapor transmission portion 221 contacts the connection flow path 103a. Moreover, the area | region of the right side is the water vapor permeation | transmission part 222, and it shows with the half in a figure. The water vapor transmission portion 222 contacts the straight flow path 150. In addition, the broken line in a figure shows the channel | path formed with the channel | path formed with the recessed part 104 and the recessed part 304, and the recessed part 140 and the recessed part 340. As described above, these passages are disposed outside the electrolyte membrane 200.

  The anode separator 300 includes an anode gas supply manifold 310, a straight channel 303, a recess 340, an anode gas discharge manifold 360, a recess 304, a cathode gas supply manifold 301, a straight channel 350, a cathode. A gas exhaust manifold 306 is formed.

  When the anode separator 300 and the cathode separator 100 are overlapped to form a single cell 1, the anode gas supply manifold 310 is in the anode gas supply manifold 110, the recess 340 is in the recess 140, and the anode gas discharge manifold 360 is in the anode gas discharge manifold 160. In addition, the recess 304 overlaps the recess 104, the cathode gas supply manifold 301 overlaps the cathode gas supply manifold 101, and the cathode gas discharge manifold 306 overlaps the cathode gas discharge manifold 106.

  The channel 303 has a connection channel 303a, a reaction channel 303b, and a connection channel 303c. When the anode separator 300 is stacked on the electrolyte membrane 200, the connection flow path 303 a contacts the water vapor transmission part 222 and intersects the straight flow path 150 with the water vapor transmission part 222 interposed therebetween.

  The anode gas supplied from the anode gas supply manifold 310 sequentially flows through the connection flow path 303a → the reaction flow path 303b → the connection flow path 303c, and the reaction at the anode electrode described above occurs when flowing through the reaction flow path 303b. Is called.

  Further, when the anode separator 300 is overlaid on the electrolyte membrane 200, the straight flow path 350 contacts the water vapor transmission part 221 and intersects the flow path 103a with the water vapor exchange part 221 interposed therebetween.

  In the single cell 1 used in the fuel cell system of the present embodiment, a passage formed by the recesses 104 and 304 is provided. This passage communicates with the connection flow path 103c. In the present embodiment, the already-reacted cathode gas is folded and circulated in the vicinity of the unreacted cathode gas using the passage formed by the recesses 104 and 304.

  As in the first embodiment, it is not necessary to turn back the already-reacted cathode gas in the cathode separator 100, and the already-reacted cathode gas can be sent to the vicinity of the unreacted cathode gas using the straight reaction channel 103b.

  Similar to the passage formed from the recesses 104 and 304, the passage formed from the recesses 340 and 140 was provided. This passage communicates with the already-reacted gas circulation region 303c. In the present embodiment, the already-reacted anode gas is folded and circulated in the vicinity of the unreacted anode gas using the passage formed from the recesses 340 and 140.

  As in the first embodiment, it is not necessary to turn back the already-reacted anode gas in the anode separator 300, and the already-reacted anode gas can be sent to the vicinity of the unreacted anode gas using the straight reaction channel 303b.

  Further, in the straight reaction channels 103b and 303b, the cathode gas and the anode gas flow more smoothly than the serpentine channels 103b and 303b of the first embodiment.

Therefore, according to this embodiment, in addition to the effects of the first embodiment, it is possible to provide a fuel cell system in which the flow path of each separator can be easily formed and the circulation of the cathode gas and the anode gas is smooth. Can do.
(Third embodiment)
FIG. 4 is a diagram showing a cross-sectional cross section of the single cell 1, the end plate 800, and the end plate 80 used in the third embodiment of the fuel cell system of the present invention. The configuration of the fuel cell system of the present embodiment is a configuration in which an end plate 800 is stacked outside the cathode separator 100 of the single cell 1 and an end plate 80 is stacked outside the anode separator 300.

  5-8 is a figure which shows each component and end plate 80,800 of the single cell 1 used for 3rd Embodiment of the fuel cell system of this invention. FIG. 5 is a view of the end plate 800 as viewed from the cathode separator 100 side. FIG. 6A is a view of the cathode separator 100 as viewed from the electrolyte membrane 200 side. FIG. 6B is a view of the electrolyte membrane 200 as viewed from the anode separator 300 side. FIG. 6C is a diagram when the anode separator 300 is seen through from the side opposite to the electrolyte membrane 200. FIG. 7 is a view of the anode separator 300 as viewed from the end plate 80 side. FIG. 8 is a view of the end plate 80 as viewed from the anode separator 300 side. In addition, the thick line in the figure of FIGS. 5-8 is a line which shows the sealing material for preventing leakage of anode gas, cathode gas, and cooling water.

  In the second embodiment, the passage formed by the recesses 104 and 304 and the passage formed by the recesses 340 and 140 are used in order to return the already reacted gas to the vicinity of the unreacted gas. In this embodiment, flow paths 804b and 840b formed in the end plate 800 are used instead of these passages.

  The end plate 800, the cathode separator 100, the electrolyte membrane 200, the anode separator 300, and the end plate 80 have the same shape, and are elongated in the side and narrower in the vicinity of the center than the widths of both sides. It has become.

  The end plate 800 includes a cathode gas supply manifold 801, a cooling water supply manifold 820, a cathode gas discharge manifold 806, a first intermediate recess 840a, a second intermediate recess 804c, and straight channels 804b and 840b. A first intermediate recess 804a, a second intermediate recess 840c, an anode gas discharge manifold 860, a cooling water discharge manifold 830, and an anode gas supply manifold 810 are formed.

  The cathode gas supply manifold 801 is formed near the corners of the end plate 800. The cathode gas supply manifold 801 is formed so as to penetrate the end plate 800.

  The cooling water supply manifold 820 is formed at one end of the end plate 800 and near the center thereof.

  The cathode gas discharge manifold 806 is disposed on the opposite side of the cathode gas supply manifold 801 with the cooling water supply manifold 820 interposed therebetween. Cathode gas exhaust manifold 806 is formed to penetrate end plate 800.

  The second intermediate recess 804c is formed next to the cathode gas supply manifold 801 through a seal material. The second intermediate recess 804c is formed by recessing the end plate 800.

  The first intermediate recess 840a is formed next to the cathode gas discharge manifold 806 via a sealing material. The first intermediate recess 840a is formed by recessing the end plate 800.

  The anode gas supply manifold 810 is disposed symmetrically with respect to the cathode gas exhaust manifold 806. The cooling water discharge manifold 830 is a cooling water supply manifold 820, the anode gas discharge manifold 860 is a cathode gas supply manifold 801, the first intermediate recess 804a is a second intermediate recess 804c, and the second intermediate recess 840c is a first intermediate recess. 840a and are arranged symmetrically.

  Near the center of the end plate 800, a flow path 804b and a flow path 840b are formed. The channel 804b is a channel that communicates the first intermediate recess 804a and the second intermediate recess 804c. The flow path 840b is a flow path that connects the first intermediate recess 840a and the second intermediate recess 840c.

  The cathode separator 100 includes a cathode gas supply manifold 101, a cooling water supply manifold 120, a cathode gas discharge manifold 106, a first intermediate hole 180, a second intermediate hole 104c, a straight channel 103, A first intermediate hole 104a, a second intermediate hole 140, an anode gas discharge manifold 160, a cooling water discharge manifold 130, an anode gas supply manifold 110, and a flow path 150 are formed.

  When the cathode separator 100 is stacked on the end plate 800, the cathode gas supply manifold 101 is placed in the cathode gas supply manifold 801, the cooling water supply manifold 120 is placed in the cooling water supply manifold 820, and the cathode gas discharge manifold 106 is placed in the cathode gas discharge manifold 806. The first intermediate hole 180 is in the first intermediate recess 840a, the second intermediate hole 104c is in the second intermediate recess 804c, the first intermediate hole 104a is in the first intermediate recess 804a, and the second intermediate hole 140 is in the second intermediate recess 804c. Further, the anode gas discharge manifold 160 is the anode gas discharge manifold 860, the cooling water discharge manifold 130 is the cooling water discharge manifold 830, and the anode gas supply manifold 110 is the anode gas supply manifold 8. To 0, overlap each other, respectively.

  Cathode gas supplied from the cathode gas supply manifold 101 sequentially flows through the connection flow path 103a → the reaction flow path 103b → the connection flow path 103c, and the reaction at the cathode electrode described above occurs when flowing through the reaction flow path 103b. Is called.

  The electrolyte membrane 200 includes a cathode gas supply manifold 201, a cooling water supply manifold 220, a cathode gas discharge manifold 206, a second intermediate hole 204, a first intermediate hole 280, a cathode gas discharge manifold 260, a first Intermediate hole 281, second intermediate hole 240, anode gas discharge manifold 210, and cooling water discharge manifold 230 are formed.

  When the electrolyte membrane 200 is overlaid on the cathode separator 100, the cathode gas supply manifold 201 is in the cathode gas supply manifold 101, the cooling water supply manifold 220 is in the cooling water supply manifold 120, the cathode gas discharge manifold 206 is in the cathode gas discharge manifold 106, The second intermediate hole 204 is in the second intermediate hole 104c, the first intermediate hole 280 is in the first intermediate hole 180, the cathode gas discharge manifold 260 is in the anode gas discharge manifold 160, and the first intermediate hole 281 is in the first intermediate hole 104a. The second intermediate hole 240 overlaps the second intermediate hole 140, the anode gas discharge manifold 210 overlaps the anode gas supply manifold 110, and the cooling water discharge manifold 230 overlaps the cooling water discharge manifold 130.

  The anode separator 300 includes an anode gas supply manifold 310, a cooling water discharge manifold 330, a second intermediate hole 380, an anode gas discharge manifold 360, a first intermediate hole 381, a straight channel 303, 2 intermediate hole 304, first intermediate hole 340a, flow path 350, cathode gas discharge manifold 306, cooling water supply manifold 320, and cathode gas supply manifold 301 are formed.

  When the anode separator 300 is stacked on the electrolyte membrane 200, the anode gas supply manifold 310 is in the anode gas supply manifold 210, the cooling water discharge manifold 330 is in the cooling water discharge manifold 230, the second intermediate hole 380 is in the second intermediate hole 240, The anode gas exhaust manifold 360 is in the anode gas exhaust manifold 260, the first intermediate hole 381 is in the first intermediate hole 281, the second intermediate hole 304 is in the second intermediate hole 204, and the first intermediate hole 340 a is in the first intermediate hole 280. Furthermore, the cathode gas discharge manifold 306 and the cathode gas discharge manifold 206 overlap with each other, the cooling water supply manifold 320 overlaps with the cooling water supply manifold 220, and the cathode gas supply manifold 301 overlaps with the cathode gas supply manifold 201, respectively.

  A flow path 303 is formed near the center of the anode palator 300. The flow path 303 is a flow path that connects the anode gas supply manifold 310 and the first intermediate hole 340a. The channel 303 has a connection channel 303a, a reaction channel 303b, and a connection channel 303c. In the present embodiment, the reaction channel 303b is straight.

  The anode gas supplied from the anode gas supply manifold 310 sequentially flows through the connection flow path 303a → the reaction flow path 303b → the connection flow path 303c, and the reaction at the anode electrode described above occurs when flowing through the reaction flow path 303b. Is called.

  The details of the surface on the end plate 80 side of the anode separator 300 (the back surface of FIG. 6C) will be described with reference to FIG.

  A cooling water channel 390 is formed on the end plate 80 side of the anode separator 300. The cooling water channel 390 is a channel that connects the cooling water supply manifold 320 and the cooling water discharge manifold 330. The cooling water flow path 390 has a certain wide width near the center of the anode separator 300, and is constricted near the cooling water supply manifold 320 and the cooling water discharge manifold 330.

  FIG. 8 is a view showing a surface of the end plate 80 on the anode separator 300 side. The end plate 80 is an end plate used for a fuel cell, and sandwiches the single cell 1 together with the end plate 800. The end plate 80 prevents the reaction gas and cooling water flowing through the anode separator 300 from leaking.

  The movement of the cathode gas, the anode gas, and the cooling water in the fuel cell system of the present embodiment will be described with reference to FIGS. First, the movement of the cathode gas will be described.

  The cathode gas flows through the cathode gas supply manifold 801 and from the cathode gas supply manifold 101 over the cathode separator 100. And cathode gas distribute | circulates the flow path 103 and distribute | circulates to the 1st intermediate hole 104a. In this process, the generated water is added to the cathode gas when it flows through the reaction channel 103b.

  The already-reacted cathode gas flows on the end plate 800 from the first intermediate hole 804a. The already-reacted cathode gas flows through the flow path 804b and flows into the second intermediate recess 804c. Then, the second intermediate holes 104c → 204 → 304 are sequentially distributed to the anode separator 300.

  The already-reacted cathode gas flows through the flow path 350 and flows to the cathode gas discharge manifold 306. At this time, water vapor contained in the already reacted cathode gas in the flow channel 350 is added to the unreacted cathode gas in the connection flow channel 103a.

  The already-reacted cathode gas is discharged to the outside through the cathode gas discharge manifold 306 → 206 → 106 → 806 sequentially.

  Next, the movement and action of the anode gas will be described.

  The anode gas flows from the anode gas supply manifold 810 to the anode separator 300 through the anode gas supply manifold 110 → 210 → 310 sequentially. The anode gas flows through the flow path 303 and flows into the first intermediate hole 340a. In this process, the anode gas sequentially flows through the connection channel 303a → the reaction channel 303b → the connection channel 303c. As the anode gas flows through the reaction flow path 303b, water that has moved to the anode electrode 270 by reverse diffusion is added.

  The already-reacted anode gas sequentially flows through the first intermediate hole 280 → 180 and then flows over the end plate 800 from the first intermediate hole 840a. The already-reacted anode gas flows through the flow path 840b to the second intermediate hole 840c. The already-reacted anode gas flows from the second intermediate hole 140 onto the cathode separator 100, flows through the flow path 150, and flows to the anode gas discharge manifold 160. At this time, water vapor contained in the already-reacted anode gas in the flow path 150 is added to the unreacted anode gas in the connection flow path 303a.

  The already-reacted anode gas is discharged through the anode gas discharge manifold 160 → 860 sequentially.

  The movement of the cooling water will be described. The cooling water sequentially flows through the cooling water supply manifold 820 → 120 → 220, and flows from the cooling water supply manifold 320 to the end plate 80 side of the anode separator 300. The cooling water flows through the cooling water flow path 390 and flows to the cooling water discharge manifold 330. The cooling water is then discharged through the cooling water discharge manifold 230 → 130 → 830 in order.

  In the fuel cell system of this embodiment, the cathode separator 100 is provided with the first intermediate hole 104a and the second intermediate hole 104c. Then, a first intermediate hole 804a and a second intermediate hole 804c are formed in the end plate 800 so that the intermediate holes communicate with the flow path 804b in the end plate 800. By doing so, the already reacted cathode gas can be folded back in the end plate 800 and circulated in the vicinity of the unreacted cathode gas.

  For this reason, in the present embodiment, it is not necessary to turn back the already-reacted cathode gas in the cathode separator 100, and the already-reacted cathode gas can be circulated in the vicinity of the unreacted cathode gas using the straight reaction channel 103b.

  A first intermediate hole 340 a was formed in the anode separator 300. The first intermediate hole 180 was formed in the cathode separator 100 and the first intermediate recess 840a was formed in the end plate 800 so that the intermediate hole and the flow path 840b in the end plate 800 were communicated. Further, a second intermediate hole 140 was formed in the cathode separator 100, and a second intermediate recess 840 c was formed in the end plate 800. By doing so, the already reacted anode gas can be folded in the end plate 800 and circulated in the vicinity of the unreacted anode gas.

  For this reason, in the present embodiment, it is not necessary to turn back the already-reacted anode gas in the anode separator 300, and the already-reacted anode gas can be circulated in the vicinity of the unreacted anode gas using the straight reaction channel 303b.

  In this embodiment, the cathode separator 100 and the anode separator 300 do not need to return the already reacted gas, so that the same effect as that of the second embodiment can be obtained.

  Furthermore, since the channels 804b and 840b in the end plate 800 are used instead of the passage formed by the recesses 104 and 304 and the recesses 140 and 340 of the second embodiment, the number of parts of the single cell 1 is reduced. be able to.

Therefore, according to the present embodiment, it is possible to provide a fuel cell system that can add the water vapor of the already reacted gas to the unreacted gas with fewer parts than the first and second embodiments.
(Fourth embodiment)
FIG. 9 is a view of the end plate 800 used in the fourth embodiment of the fuel cell system of the present invention as viewed from the cathode separator 100 side, and corresponds to FIG.

  In this embodiment, the cathode separator 100 shown in FIG. 6 (A) is used, the electrolyte membrane 200 shown in FIG. 6 (B) is used, and the anode separator 300 is shown in FIG. 6 (C). The end plate 80 shown in FIG. 8 is used.

  In FIG. 5, the flow path 804b connecting the first intermediate recess 804a to the second intermediate recess 804c and the flow path 840b connecting the first intermediate recess 840a to the second intermediate recess 840c are formed. Then, instead of the first intermediate recess 804a, the first intermediate hole 805a, the second intermediate hole 805c instead of the second intermediate recess 804c, the first intermediate hole 850a instead of the first intermediate recess 840a, the second intermediate A second intermediate hole 850c is formed instead of the recess 840c. Then, the cathode three-way valve 901 is provided to communicate the first intermediate hole 805a to the second intermediate hole 805c, and the cathode three-way valve 901 is switched according to the operating state, so that the first intermediate hole 805a to the cathode gas discharge manifold 806 are switched. Communicate. In addition, an anode three-way valve 902 is provided to communicate the first intermediate hole 805a to the second intermediate hole 805c, and the anode three-way valve 902 is switched according to the operating state so that the first intermediate hole 850a to the anode gas discharge manifold 860 Communicate.

  According to this embodiment, the addition of water vapor to the unreacted gas can be controlled by the cathode three-way valve 901 and the anode three-way valve 902. That is, when it is necessary to add the water vapor of the already reacted cathode gas to the unreacted cathode gas, the cathode three-way valve 901 is switched to connect the first intermediate hole 805a to the second intermediate hole 805c. When it is not necessary to add the water vapor of the already reacted cathode gas to the unreacted cathode gas, the cathode three-way valve 901 is switched to connect the first intermediate hole 805a to the cathode gas discharge manifold 806. When it is necessary to add the water vapor of the already reacted anode gas to the unreacted anode gas, the anode three-way valve 902 is switched to communicate the first intermediate hole 805a to the second intermediate hole 805c. When it is not necessary to add the water vapor of the already reacted anode gas to the unreacted anode gas, the anode three-way valve 902 is switched to communicate the first intermediate hole 850a to the anode gas discharge manifold 860.

  As described above, according to this embodiment, the addition of water vapor to the unreacted gas can be controlled by the cathode three-way valve 901 and the anode three-way valve 902.

  The present invention is not limited to the embodiment described above, and various modifications and changes can be made within the scope of the technical idea, and it is obvious that these are equivalent to the present invention.

  In the first and second embodiments, cooling water may be circulated between the cathode separator 100 and the anode separator 300 as in the third embodiment. By doing so, in addition to the effects of the first and second embodiments, the single cell 1 can be cooled during operation of the fuel cell.

  In the third and fourth embodiments, a plurality of single cells 1 constituting the fuel cell system 3 may be used. Even in this case, the same effect as the third embodiment can be obtained.

  In the fourth embodiment, any one of the cathode three-way valve 901 and the anode three-way valve 902 may be used. In this way, only one of the unreacted cathode gas and the unreacted anode gas can be controlled and humidified.

  In the porous body 200b sandwiching the water vapor permeable portions 221 and 222 of the first to fourth embodiments, hydrophilic treatment is performed on the flow path side through which the already reacted gas flows, and water repellent treatment is performed on the side through which the unreacted gas flows. Also good. By doing in this way, the efficiency of permeation of water vapor from the already reacted gas to the unreacted gas can be increased, and the water vapor permeating portion can be reduced.

  In the first to fourth embodiments, water vapor may be added from the already reacted gas to the unreacted gas only in either the cathode gas or the anode gas. Even in such a case, the same effect as the fuel cell system of the present invention can be obtained.

  The water vapor permeation portion of the first to fourth embodiments may be made thinner than the portion sandwiched between the cathode electrode and the anode electrode. By doing in this way, the area of a water vapor transmission part can be made small and the effect equivalent to 4th Embodiment can be acquired from 1st Embodiment.

1 is a diagram showing a single cell 1 used in a first embodiment of a fuel cell system according to the present invention. It is a figure which shows the surface of each component of the single cell 1 used for 1st Embodiment of the fuel cell system by this invention. It is a figure which shows the surface of each component of the single cell 1 used for 2nd Embodiment of the fuel cell system by this invention. It is a lamination | stacking cross section of the single cell 1 used for 3rd Embodiment of the fuel cell system by this invention, and end plate 80,800. It is a figure which shows the surface of the end plate 800 used for 3rd Embodiment of the fuel cell system by this invention. It is a figure which shows the surface of each component of the single cell 1 used for 3rd Embodiment of the fuel cell system by this invention. It is a figure which shows the surface of the back side of the anode separator 300 of the single cell 1 used for 3rd Embodiment of the fuel cell system by this invention. It is a figure which shows the surface of the end plate 80 of the single cell 1 used for 3rd Embodiment of the fuel cell system by this invention. It is a figure which shows the relationship between the end plate 800 of the single cell 1 used for 4th Embodiment of the fuel cell system by this invention, the cathode three-way valve 901, and the anode three-way valve 902. FIG.

Explanation of symbols

1 Single cell 1 (fuel cell system)
100 Cathode separator (first separator)
101 Cathode gas supply manifold (supply manifold)
200 Electrolyte membrane (solid polymer membrane)
207 Cathode electrode 270 Anode electrode 300 Anode separator (second separator)
221 and 222 Water vapor transmission part (solid polymer membrane)
150,350 Straight channel (passage through which the reaction gas flows)
103a, 303a Connection flow path (unreacted gas passage)
C Cathode contact area A Anode contact area 103b Reaction flow path 204 Communication hole 901 Cathode three-way valve (three-way valve)
902 Anode three-way valve (three-way valve)

Claims (10)

A solid polymer film on which a cathode electrode and an anode electrode are formed;
A first separator and a second separator that sandwich the solid polymer film;
A fuel cell system comprising:
The first separator is formed with an unreacted passage through which unreacted gas supplied from the supply manifold and not yet reacted flows, and a reaction passage for guiding the gas that has flowed through the unreacted passage to the electrode,
The second separator is formed with a passage that intersects the unreacted passage of the first separator with the solid polymer membrane interposed therebetween, and that flows through the reaction passage and through which the reacted gas containing reaction water flows. And
Water contained in the already reacted gas flowing through the passage formed in the second separator permeates the solid polymer membrane and humidifies the unreacted gas flowing in the unreacted passage of the first separator. ,
A fuel cell system. The reaction passage has a serpentine shape,
The fuel cell system according to claim 1. The reaction passage is straight.
The fuel cell system according to claim 1. The already-reacted gas that has flowed through the reaction path of the first separator flows through the path of the second separator through the hole formed in the solid polymer film.
The fuel cell system according to any one of claims 1 to 3, wherein The already-reacted gas that has flowed through the reaction path of the first separator flows through the path of the second separator through the path formed on the outer periphery of the first separator.
The fuel cell system according to any one of claims 1 to 3, wherein An end plate disposed outside the first separator and having a passage formed therein;
The already reacted gas that has flowed through the reaction passage of the first separator flows through the passage of the second separator through the passage formed in the end plate.
The fuel cell system according to any one of claims 1 to 3, wherein A three-way valve that causes the already-reacted gas that has flowed through the reaction passage of the first separator to flow into the passage of the second separator or the exhaust manifold;
The fuel cell system according to any one of claims 1 to 3, wherein The portion of the solid polymer membrane that is permeable to water is thinner than other portions of the solid polymer membrane,
The fuel cell system according to any one of claims 1 to 6, wherein The portion of the solid polymer membrane that transmits water is formed of a porous body.
The fuel cell system according to any one of claims 1 to 7, wherein The porous body is subjected to a hydrophilic treatment on the second separator side and a water repellent treatment on the first separator side.
The fuel cell system according to claim 8.

Images