JP2005285694A - Solid polymer fuel cell and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell and a fuel cell system capable of recovering water generated in the fuel cell while suppressing a system becoming huge size. <P>SOLUTION: The fuel cell comprises an oxidant electrode 3 and a fuel electrode 4 provided on both main surfaces of an electrolyte membrane 2, and reaction gas passages 8, 9 for circulating oxidant gas or fuel gas between the respective electrodes 3, 4, and has separators 6, 7 each having a laminating face larger than the electrodes 3, 4. A condensation heat exchange part 14 using the oxidant gas as a heat source after flowing in the reaction gas passage 8 is provided at a region (region other than a region A) other than a region overlapping with the electrodes 3, 4 on the laminating faces of the separators 6, 7. The condensation heat exchange part 14 is constructed so as to be able to exchange heat between a post-reaction oxidant gas passage 16 in which the oxidant gas after reaction flows and a first coolant passage 15a in which a coolant before cooling the reaction region flows. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polymer electrolyte fuel cell and a fuel cell system using the same. In particular, the present invention relates to a structure of a polymer electrolyte fuel cell for making a fuel cell system compact.

As a conventional fuel cell system, a heat recovery system condensing heat exchanger uses the exhaust fluid from the electricity generation system as a heat source, heat is supplied from the water supply system as a heat source, and heat is exchanged into hot water, and the hot water is used as a heat utilization part. Water is circulated in the hot water supply means to supply, the steam separator for premixing the drain water generated during heat exchange with the condensation heat exchanger to the fuel to be supplied to the fuel reforming system, and the battery body of the electricity generating system And a circulation path for exchanging heat and supplying the hot water to a heat utilization section is known. The drain water contained in the combustion exhaust gas is effectively and sufficiently recovered, and the recovered drain water is effectively used (for example, see Patent Document 1).
International Publication No. 02/23661 Pamphlet

  The purpose of the heat and water recovery system is to recover the generated water and water generated in the fuel cell body. The generated water may exist as droplets or may exist as water vapor mixed in the exhaust gas. When it exists as a droplet, it can be easily separated by utilizing the difference in density from the gas, but when it exists as water vapor, it is condensed to recover water and heat.

  In the above background art, liquid water and exhaust gas are heat-exchanged in the condensation heat exchanger, and the drain water generated by the heat exchange is recovered in the buffer part of the condensation heat exchanger and used in the system. Yes. In such a case, a condensation heat exchanger having a heat exchange area necessary for sufficiently recovering drain water by condensation by heat exchange and a buffer part as a water recovery part is required. Further, a refrigerant system for circulating a refrigerant for exchanging heat with the exhaust gas to the condensation heat exchanger is required. Therefore, there has been a problem that the fuel cell system becomes complicated and becomes enormous.

  In view of the above problems, an object of the present invention is to provide a polymer electrolyte fuel cell and a fuel cell system that can recover water generated by a fuel cell while suppressing the enlarging of the system.

  The present invention includes a cathode electrode layer and an anode electrode layer provided on both main surfaces of an electrolyte membrane, and a reaction gas flow path for flowing an oxidant gas or a fuel gas between the electrode layers, and a laminated surface Comprising a separator larger than the electrode layer. A condensing heat exchanging portion having at least one of the oxidant gas and the fuel gas after circulation of the reaction gas flow path as a heat source is provided in a region other than the electrode layer on the separator lamination surface.

  Thus, by using a fuel cell including a condensation heat exchanging section that uses the oxidant gas or fuel gas after circulation of the reaction gas flow path as a heat source in a region other than the electrode layer on the separator stacking surface, the fuel cell main body is used. Even if the size of the system becomes slightly larger, a condensing heat exchanger and a refrigerant system for condensing heat exchange are not required, and the entire system can be improved in efficiency and downsized. In addition, the water in the oxidant gas or the fuel gas after flowing through the reaction gas channel is easily condensed by heat exchange. As a result, water generated by the fuel cell can be recovered while suppressing the enlargement of the system.

  A first embodiment will be described. A cross section of the fuel cell 1 is shown in FIG. Here, the fuel cell 1 is constituted by a stack formed by laminating a plurality of unit cells 1a. However, the present invention is not limited to this and may be constituted by one unit cell 1a.

  A membrane electrode assembly 5 in which a unit cell 1a is sandwiched between a solid polymer electrolyte membrane (hereinafter referred to as an electrolyte membrane) 2 such as a perfluorocarbon sulfonic acid membrane between a pair of an oxidant electrode 3 and a fuel electrode 4. And an oxidant gas separator 6 and a fuel gas separator 7 sandwiched from the outside. The oxidant electrode 3 and the fuel electrode 4 are reaction regions that generate a power generation reaction, and are composed of carbon paper or carbon cloth having a catalyst such as platinum on the electrolyte membrane 2 side. The catalyst may be applied to the electrolyte membrane 2 side.

  The oxidant gas separator 6 and the fuel gas separator 7 are each made of a dense carbon material. A groove-like oxidant gas flow path 8 is formed on the surface 6a of the oxidant gas separator 6 facing the oxidant electrode 3, and the oxidant gas is supplied to the oxidant electrode 3 by flowing the oxidant gas therethrough. Supply. Further, a groove-like fuel gas flow path 9 is formed on the surface 7 a facing the fuel electrode 4 of the fuel gas separator 7, and the fuel gas is supplied to the fuel electrode 4 by flowing the fuel gas therethrough. Further, a groove-like refrigerant flow path 15 (15b) is formed on the back surface 7b of the surface 7a of the fuel gas separator 7, and the temperature of the unit cell 1a is adjusted by circulating the refrigerant therethrough. The fuel cell 1 is configured by stacking a plurality of such unit cells 1a. When the unit cells 1a are stacked, the back surface 7b of the fuel gas separator 7 in which the refrigerant channel 15 (15b) is formed is in contact with the back surface 6b of the adjacent oxidant gas separator 6.

  In addition, a manifold is provided in a region other than the region A that overlaps the reaction region of the fuel cell 1. As will be described later, the oxidant gas, the fuel gas, and the refrigerant are circulated in the stacking direction, and are distributed and recovered to the oxidant gas flow path 8, the fuel gas flow path 9, and the refrigerant flow path 15, and the fuel gas. A manifold 12 and a refrigerant manifold 13 are provided. FIG. 1 shows only the refrigerant manifold 13.

  Next, details of the oxidant gas separator 6 and the fuel gas separator 7 will be described with reference to the plan views of FIGS. FIG. 2 is a plan view of the surface 6 a facing the oxidant electrode 3 of the oxidant gas separator 6. 3A is a plan view of the surface 7a facing the fuel electrode 4 of the fuel gas separator 7, and FIG. 3B is a plan view of the back surface 7b thereof.

  As shown in FIG. 2, an oxidant gas flow path 8 is formed in a region A of the surface 6 a of the oxidant gas separator 6 that overlaps the reaction region (oxidant electrode 3). Further, as shown in FIG. 3A, a fuel gas flow path 9 is formed in a region A of the surface 7a of the fuel gas separator 7 that overlaps the reaction region (fuel electrode 4). The oxidant gas flow path 8 and the fuel gas flow path 9 are each constituted by a plurality of parallel linear grooves, but this is not restrictive. Further, as shown in FIG. 3B, a second refrigerant flow path 15 b for circulating a refrigerant for adjusting the temperature of the reaction region is provided in a region A overlapping the reaction region of the back surface 7 b of the fuel gas separator 7. Here, in the region A, the flow directions of the oxidant gas, the fuel gas, and the refrigerant are substantially orthogonal, but this is not limited thereto.

  Further, as shown in FIG. 2, a post-reaction oxidant gas flow path 16 for circulating the oxidant gas that has become high temperature and high humidity after the power generation reaction is provided outside the region A on the surface 6a side of the oxidant gas separator 6. Provide. Here, the post-reaction oxidant gas flow path 16 is constituted by a groove having a plurality of heat exchange fins on the bottom surface. Further, as shown in FIG. 3 (a), the first refrigerant flow in which the refrigerant before the temperature adjustment of the reaction region flows in the region overlapping the post-reaction oxidant gas flow path 16 on the surface 7a of the fuel gas separator 7. A path 15a is provided. The post-reaction oxidant gas flow path 16 and the first refrigerant flow path 15a constitute a condensation heat exchange section 14.

  Here, the oxidant gas separator 6 and the fuel gas separator 7 are in direct contact with the back surfaces 6a and 7a. Therefore, heat exchange is performed between the oxidant gas after the reaction and the refrigerant introduced from the outside through the bottom surface of the post-reaction oxidant gas flow channel 16 and the bottom surface of the first refrigerant flow channel 15a. In addition, although the structure of the back surface 6b of the oxidizing gas separator 6 is not shown in figure, it is set as a plane, for example. In addition, heat exchange is performed through the electrolyte membrane 2 sandwiched between the openings of the grooves constituting the post-reaction oxidant gas channel 16 and the first refrigerant channel 15a.

  Further, an oxidant gas manifold 11, a fuel gas manifold 12, and a refrigerant manifold 13 are provided outside the region A. The oxidant gas manifold 11 includes a first oxidant gas manifold 11 a connected to the outside of the fuel cell 1 and the upstream end of the oxidant gas flow path 8, a downstream end of the oxidant gas flow path 8, and a post-reaction oxidant gas flow path. A first dioxide gas manifold 11b connected to the upstream end of the fuel cell 16 and a third oxidizing gas manifold 11c connected to the downstream end of the post-reaction oxidizing gas channel 16 and the outside of the fuel cell 1 are provided. Further, as the fuel gas manifold 12, a first fuel gas manifold 12 a connected to the outside of the fuel cell 1 and the upstream end of the fuel gas passage 9, a first fuel gas manifold 12 a connected to the downstream end of the fuel gas passage 9 and the outside of the fuel cell 1. A dual fuel gas manifold 12b is provided. Furthermore, as the refrigerant manifold 13, the first refrigerant manifold 13a connected to the outside of the fuel cell 1 and the upstream end of the first refrigerant flow path 15a, the downstream end of the first refrigerant flow path 15a, and the upstream end of the second refrigerant flow path 15b And a third refrigerant manifold 13c connected to the outside of the fuel cell 1 and a downstream end of the second refrigerant flow path 15b.

  The first refrigerant manifold 13a and the second refrigerant manifold 13b are configured to sandwich the post-reaction oxidant gas flow path 16. Here, along the flow axis direction of the post-reaction oxidant gas flow channel 16, the first refrigerant manifold 13a is disposed on one side and the second refrigerant manifold 13b is disposed on the other side. At this time, the refrigerant flows in the first refrigerant flow path 15a in a substantially vertical direction with respect to the oxidant gas after the reaction in the post-reaction oxidant gas flow path 16. Thus, although the post-reaction oxidant gas flow path 16 and the flow in the first refrigerant flow path 15a are substantially vertical here, this is not restrictive. Moreover, although the 1st refrigerant | coolant manifold 13a and the 2nd refrigerant | coolant manifold 13b are each comprised by the multiple (three here) through-hole, it is not this limitation.

  Note that the second dioxide agent gas manifold 11b is not necessarily a through hole. You may comprise by the groove | channel provided in the surface of the oxidizing agent gas separator 6. FIG. Further, a gasket (not shown) that seals the fluid flowing through each of the flow paths 8, 9, 15 and the manifolds 11, 12, 13 is provided to prevent mixing between the fluids.

  Next, the configuration of a fuel cell system using such a fuel cell 1 will be described with reference to FIG.

  The fuel cell system includes a refrigerant loop 21 that is a circulation path for introducing the refrigerant into the fuel cell 1. The refrigerant loop 21 includes a pump 22 that circulates the refrigerant, a radiator 23 that radiates the refrigerant, and a refrigerant accumulation unit 24 that accumulates the refrigerant. Here, for example, pure water is used as the refrigerant.

  Further, an oxidant inlet pipe 25 i and a fuel inlet pipe 26 i for introducing oxidant gas and fuel gas into the fuel cell 1, an oxidant outlet pipe 25 o and a fuel outlet pipe 26 o for discharging from the fuel cell 1 are provided. The oxidant outlet pipe 25o includes a buffer part 27 that separates and recovers moisture in the oxidant exhaust gas, and a condensed water pipe 28 that takes out water from the buffer part 27. Although not shown here, the extracted water can be used for humidification of the electrolyte membrane 2 or for the refrigerant of the fuel cell 1.

  Next, the flow state of oxidant gas, fuel gas and refrigerant in such a fuel cell system will be described.

  The oxidant gas introduced into the fuel cell 1 from the oxidant inlet pipe 25i is distributed to the oxidant gas flow path 8 of each unit cell 1a through the first oxidant manifold 11a. Further, the fuel gas introduced into the fuel cell 1 from the fuel inlet pipe 26i is distributed to the fuel gas flow path 9 of each unit cell 1a through the first fuel gas manifold 12a. The oxidant gas flowing through the oxidant gas flow path 8 diffuses into the oxidant electrode 3, and the fuel gas flowing through the fuel gas flow path 9 diffuses into the fuel electrode 4 and near the electrolyte membrane 2 as follows. Generates a power generation reaction.

Oxidant electrode 3 side: _1/2 O ₂ + 2H ⁺ + 2e ⁻ → H ₂ O
Fuel electrode 4 side: H ₂ → 2H ⁺ + 2e ⁻
This power generation reaction is an exothermic reaction, and accordingly, the temperatures of the oxidant gas and the fuel gas rise. Moreover, since water is generated as a product on the oxidant electrode 3 side, the humidity of the oxidant gas increases. Furthermore, the humidity of the fuel gas also increases due to evaporation from the electrolyte membrane 2 or the like.

  The high-temperature fuel gas that was not used for power generation at the fuel electrode 4 was collected in the second fuel gas manifold 12b, discharged from the fuel cell 1 to the fuel outlet pipe 26o, and burned by, for example, a combustor (not shown). Thereafter, the fuel cell system is discharged. On the other hand, the high-temperature and high-humidity oxidant gas that has not been used for power generation at the oxidant electrode 3 is collected in the second dioxide gas manifold 11b and redistributed to the oxidant gas channel 16 after the reaction.

  When flowing through the post-reaction oxidant gas flow path 16 constituting the condensation heat exchange unit 14, heat exchange is performed between the post-reaction oxidant gas and the refrigerant flowing through the first refrigerant flow path 15a. Thereby, oxidant gas temperature falls and the condensation of the water contained in oxidant gas after reaction arises. Here, since the refrigerant that performs heat exchange is a refrigerant at a relatively low temperature before heat exchange with the reaction region, condensation in the oxidant gas after the reaction is promoted.

  The post-reaction oxidant gas that has undergone condensation in the post-reaction oxidant gas flow path 16 is collected in the third oxidant gas manifold 11c and discharged from the fuel cell 1 to the oxidant outlet pipe 25o. The discharged oxidant exhaust gas is separated and collected from the moisture condensed in the buffer unit 27, and then discharged from the fuel cell system via a combustor (not shown), for example. On the other hand, the water collected by the buffer unit 27 passes through the condensed water pipe 28 and is used for humidification of the electrolyte membrane 2 and refrigerant.

  On the other hand, the refrigerant for adjusting the temperature of the fuel cell 1 is introduced into the fuel cell 1 from the refrigerant loop 21 by the pump 22 and passes through the first refrigerant manifold 13a and is provided on the surface 7a of the fuel gas separator 7 of the unit cell 1a. The refrigerant is distributed to one refrigerant flow path 15a. When the refrigerant flows through the first refrigerant flow path 15a constituting the condensation heat exchange unit 14, the refrigerant receives heat from the post-reaction oxidant gas flow path 16 adjacent in the cell stacking direction, and the refrigerant temperature rises. At this time, since condensation occurs in the oxidant gas flow path 16 after the reaction, the refrigerant receives latent heat associated with the condensation in addition to heat from the high-temperature oxidant gas.

  The refrigerant whose temperature has risen is collected in the second refrigerant manifold 13 b and distributed to the second refrigerant flow path 15 b formed on the back surface 7 b of the fuel gas separator 7. Here, if the temperature difference between the refrigerant and the reaction region is larger than necessary, supercooling occurs in the reaction region overlapping the vicinity of the inlet of the second refrigerant flow path 15b, and power generation efficiency decreases. However, since the refrigerant heat is raised in the condensation heat exchanging section 14 and then introduced into the reaction region, a decrease in power generation efficiency due to overcooling is suppressed.

  When the refrigerant flows through the second refrigerant flow path 15b, the refrigerant further absorbs heat generated by the power generation reaction, becomes a high temperature state, and is recovered by the third refrigerant manifold 13c, and is transferred from the fuel cell 1 to the refrigerant loop 21. Discharged.

  In this way, in the condensation heat exchanging unit 14, heat exchange is performed between the existing reaction gas (oxidant gas after the reaction) that has become high temperature and high humidity by the power generation reaction and the relatively low temperature refrigerant. A condensing heat exchanger for condensing water in the reaction gas and a refrigerant system therefor are not required. Moreover, since the temperature of the reaction region is adjusted using the refrigerant after heat exchange is performed in the condensation heat exchange unit 14, a decrease in power generation efficiency due to local supercooling is suppressed.

  Here, the oxidant gas after the reaction is introduced into the condensation heat exchanging unit 14, but the fuel gas after the reaction may be introduced. In the condensation heat exchanging section 14, the same effect can be obtained by exchanging heat between the fuel gas that has become high in temperature after the reaction and has a relatively high water content and the refrigerant used for cooling the fuel cell 1. it can.

  Further, both the post-reaction oxidant gas flow channel 16 and the first refrigerant flow channel 15a are provided on the surfaces 6a and 7a of the separators 6 and 7 on the side facing the membrane electrode assembly 5, but this is not restrictive. Either one may be formed on the back surface 6b, 7b side.

  Next, the effect of this embodiment will be described.

  Between the oxidant electrode 3 and the fuel electrode 4 provided on both main surfaces of the electrolyte membrane 2 and the reaction gas flow paths 8 and 9 for flowing the oxidant gas or the fuel gas between the electrodes 3 and 4, respectively. The laminated surface includes separators 6 and 7 that are larger than the electrodes 3 and 4. Condensation using at least one of the oxidant gas or fuel gas after flowing through the reaction gas flow path 8 or 9 as a heat source in a region other than the electrodes 3 and 4 on the stacked surfaces of the separators 6 and 7 (regions other than the region A) A heat exchange unit 14 is provided. Here, post-reaction oxidant gas after circulation of the oxidant gas flow path 8 is used as a heat source. As a result, even if the size of the main body of the fuel cell 1 is slightly increased, a condensing heat exchanger and a refrigerant system for condensing heat exchange are not required, and the efficiency and compactness of the entire system can be achieved. In addition, it is possible to recover water of water vapor in the oxidant gas after the reaction, thereby improving water recovery efficiency. As a result, water generated in the fuel cell 1 can be recovered while suppressing an increase in the size of the system. As a result, water generated in the fuel cell 1 can be recovered while suppressing an increase in the size of the system.

  A post-reaction oxidant gas flow path 16 that circulates the oxidant gas flow path 8 provided between the oxidant electrode 3 and the oxidant gas separator 6 as the condensation heat exchange unit 14, and a reaction A first refrigerant channel 15a that is provided in a region overlapping the post-oxidant gas channel 16 in the stacking direction and distributes a refrigerant for adjusting the temperature of the fuel cell 1; Thereby, heat exchange can be performed between the oxidant gas that has become high temperature and high humidity due to the reaction and the refrigerant in the fuel cell 1 to condense and recover the water contained in the oxidant gas. .

  The first refrigerant flow path 15 a is provided in the upstream portion of the refrigerant path in the fuel cell 1. As a result, heat exchange between the relatively low-temperature refrigerant before the heat generated by the power generation reaction and a high temperature is performed and the oxidant gas after the reaction is performed, so that condensation can be promoted. Moreover, the supercooling by a refrigerant | coolant can be suppressed and electric power generation efficiency can be maintained.

  By using such a fuel cell 1 for a fuel cell system, water management can be improved while achieving a compact system.

  Next, a second embodiment will be described. FIG. 5 shows a plan view of the surface 6 a of the oxidant gas separator 6. FIG. 6A shows a plan view of the front surface 7a of the fuel gas separator 7, and FIG. 6B shows a plan view of the back surface 7b. Hereinafter, a description will be given centering on differences from the first embodiment.

  Each of the oxidant gas separator 6 and the fuel gas separator 7 is made of, for example, a corrosion-resistant metal material. Also, pure water is used as the refrigerant. Furthermore, the fuel cell 1 is installed so that the stacking direction of the unit cells 1a is substantially vertical during operation.

  Similar to the first embodiment, a region A overlapping the reaction region provided with the oxidant gas flow path 8 and the fuel gas flow path 9, a post-reaction oxidant gas flow path 16 and a first refrigerant flow path 15a are provided. A condensation heat exchange unit 14 is provided. Here, the second refrigerant flow path 15b is not provided on the back surface 7b of the fuel gas separator 7, but this is not restrictive.

  Further, the humidifying part 34 is provided outside the area A. Here, the condensing heat exchange unit 14 and the humidifying unit 34 are configured to sandwich the region A. A humidifying portion 34 is provided on the surface 7a of the oxidant gas separator 6 as shown in FIG. 5 and on the surface 7a of the fuel gas separator 7 as shown in FIG. 6A. The third refrigerant flow path 15c is used. The pre-reaction oxidant gas flow path 36, the oxidant gas flow path 8, and the post-reaction oxidant gas flow path 16 have substantially the same flow axis direction, but this is not restrictive.

  Further, an oxidant gas manifold 31, a fuel gas manifold 32, and a refrigerant manifold 33 are provided outside the region A.

  The oxidant gas manifold 31 includes a first oxidant gas manifold 31 a connected to the oxidant inlet pipe 25 i and the upstream end of the pre-reaction oxidant gas flow path 36, and a downstream end of the pre-reaction oxidant gas flow path 36 and the oxidation. A second dioxide agent gas manifold 31 b that connects the upstream end of the agent gas flow path 8 is provided. Further, a third oxidant gas manifold 31c connected to the downstream end of the oxidant gas flow path 8 and the upstream end of the post-reaction oxidant gas flow path 16, the downstream end of the post-reaction oxidant gas flow path 16 and the oxidant outlet A fourth oxidant gas manifold 31d connected to the pipe 25o is provided. As in the first embodiment, as the fuel gas manifold 32, the first fuel gas manifold 32a connected to the upstream end of the fuel inlet pipe 26i and the fuel gas passage 9, the downstream end of the fuel gas passage 9, and the fuel A second fuel gas manifold 32b connected to the outlet pipe 26o is provided. Further, as the refrigerant manifold 33, a first refrigerant manifold 33a connected to the refrigerant loop 21 and the upstream end of the first refrigerant flow path 15a, a first end connected to the downstream end of the first refrigerant flow path 15a and an external flow path (not shown). Two refrigerant manifolds 33b are provided. Further, a third refrigerant manifold 33c connected to the external flow path (not shown) and the upstream end of the third refrigerant flow path 15c, and a fourth refrigerant manifold 33d connected to the downstream end of the third refrigerant flow path 15c and the refrigerant loop 21 are provided. .

  The third refrigerant manifold 33c and the fourth refrigerant manifold 33d are constituted by a plurality of through holes. Here, the third refrigerant manifold 33c is arranged along one side surface of the pre-reaction oxidant gas flow path 36, and the fourth refrigerant manifold 33d is arranged along the other side surface. Thus, here, the flow direction of the oxidant gas in the pre-reaction oxidant gas flow path 36 constituting the humidifying section 34 and the third refrigerant flow path connected to the third and fourth refrigerant manifolds 33c and 33d. Although the flow direction of the refrigerant in 15c is made substantially orthogonal, it is not limited to this.

  Further, as shown in FIG. 5, in the upstream region of the pre-reaction oxidant gas flow path 36, a micro hole 37 is provided on the bottom surface of the groove constituting the pre-reaction oxidant gas flow path 36. The minute hole 37 is a hole penetrating the oxidant gas manifold 6 and the fuel gas manifold 7 which are in contact with each other on the back surfaces 6b and 7b. In other words, the pre-reaction oxidant gas flow path 36 and the third refrigerant flow path 15c are configured to communicate with each other through the micro holes 37. Here, the plurality of micropores 37 are equally provided on the upstream side of the pre-reaction oxidant gas flow path 36, but this is not restrictive. The micro hole 37 is a hole having a diameter of about 50 μm provided by, for example, etching.

  Further, the downstream side of the pre-reaction oxidant gas flow path 36 has a shape in which droplets in the oxidant gas tend to stay. Here, the cross section along the laminated surface of the ribs 38 constituting the side surfaces of the grooves constituting the pre-reaction oxidant gas flow path 36 is configured to have a continuous mountain shape. That is, the side surface is configured to be uneven with respect to the flow direction of the oxidant gas. Here, only the rib 38 constituting one side surface of the pre-reaction oxidant gas flow path 36 has a mountain shape, but this is not restrictive. You may comprise so that it may have a mountain shape about both sides | surfaces, and you may provide a triangular unevenness | corrugation in a groove bottom face.

  Next, the configuration of a fuel cell system using such a fuel cell 1 will be described with reference to FIG. Here, the description will focus on parts different from FIG.

  Here, the refrigerant storage unit 24 provided in the refrigerant loop 21 is provided with a discharge line 41 and a valve 42 for selectively discharging a part of the refrigerant accumulated inside. Further, a condensed water pipe 43 for collecting the water separated and collected by the buffer unit 27 in the refrigerant storage unit 24 is provided.

  Next, the flow state of the oxidant gas, fuel gas, and refrigerant will be described.

  The refrigerant introduced into the fuel cell 1 from the refrigerant loop 21 is introduced from the first refrigerant manifold 33a to the first refrigerant flow path 15a provided in the condensation heat exchanging section 14, and exchanges heat with the oxidant gas after the reaction. After that, it is collected in the second refrigerant manifold 33b. The second refrigerant manifold 33b is configured substantially along the reaction region in the stacking direction, and removes heat generated by the power generation reaction when the refrigerant flows. The refrigerant flowing through the second refrigerant manifold 33b is introduced into the third refrigerant manifold 33c through an external flow path (not shown). The third refrigerant manifold 33c is also configured substantially along the reaction region in the stacking direction, and the reaction region is cooled as the refrigerant flows therethrough. The refrigerant is distributed from the third refrigerant manifold 33c to the third refrigerant flow path 15c, and is supplied to the pre-reaction oxidant gas flow path 36 side through a minute hole 37 partially formed in the groove bottom surface. Since the refrigerant cools the reaction region before being supplied to the pre-reaction oxidant gas flow path 36, relatively high-temperature water is supplied to the pre-reaction oxidant gas flow path 36. The refrigerant that has not been supplied to the pre-reaction oxidant gas flow path 36 side is recovered by the fourth refrigerant manifold 33d and discharged to the refrigerant loop 21 side.

  On the other hand, the oxidant gas is distributed from the oxidant inlet pipe 25i through the first oxidant gas manifold 31a to the pre-reaction oxidant gas flow path 36 constituting the humidifying section 34. On the upstream side of the pre-reaction oxidant gas flow path 36, a part of the water (refrigerant) mixed in the flow path through the micro holes 37 evaporates, and the flowing oxidant gas is humidified. As described above, since relatively high-temperature water is mixed here, evaporation of water into the oxidant gas is promoted. After water is supplied from the micropores 37, the oxidant gas flows along the mountain-shaped ribs 38 on the downstream side of the pre-reaction oxidant gas flow path 36. At this time, surplus water mixed in the oxidant gas stays on the side surface constituted by the ribs 38.

  The oxidant gas that has flowed through the pre-reaction oxidant gas flow path 36 is collected in the second dioxide gas manifold 31 b and distributed to the oxidant gas flow path 8. At this time, since the stacking direction of the unit cells 1a is set to a substantially vertical direction, the droplet-like surplus water is separated below the second dioxide gas manifold 31b, and only the gas phase is distributed to the oxidant gas flow path 8. .

  As in the first embodiment, the oxidant gas flowing through the oxidant gas flow path 8 is used for the reaction at the oxidant electrode 3, and the relatively high temperature and high humidity oxidant gas after the reaction is used as the third oxidant gas. It supplies to the post-reaction oxidant gas flow path 16 which comprises the condensation heat exchange part 14 via the manifold 31c. After the reaction, heat exchange with the refrigerant flowing through the first refrigerant flow path 15a is performed in the oxidant gas flow path 16, and then discharged to the oxidant outlet pipe 25o via the fourth oxidant gas manifold 31d. Further, after gas-liquid separation in the buffer unit 27, the oxidant exhaust gas is discharged through a combustor or the like (not shown), and the condensed water is collected in the refrigerant storage unit 24 through the condensed water pipe 43. As described above, the refrigerant is mixed in the oxidant gas through the micro holes 37, but is condensed in the condensation heat exchange unit 14 and recovered again in the refrigerant system through the buffer unit 27. Can be maintained.

  The fuel gas is the same as in the first embodiment.

  As described above, the humidifying unit 34 is provided, and the oxidant gas is humidified by efficiently evaporating the relatively high-temperature refrigerant after cooling the reaction region into the oxidant gas before being introduced into the reaction region. . At this time, the water condensed in the heat exchanger 14 is collected in the refrigerant system to maintain the flow rate of the refrigerant.

  Although the oxidant gas separator 6 and the fuel gas separator 7 are separately configured here, they may be integrated into a single separator. In this case, the minute hole 37 is a through-hole penetrating the separator in the stacking direction.

  Next, the effect of this embodiment will be described. Only the effects different from those of the first embodiment will be described below.

  A humidifying unit 34 is provided for humidifying at least one of the oxidant gas and the fuel gas before being introduced into the electrodes 3 and 4. The pre-reaction gas flow path that circulates at least one of the oxidant gas or the fuel gas before flowing through the reaction gas flow path 8 or 9 provided between the electrode 3 or 4 and the separator 6 or 7 as the humidifying section 34. (36) and a third refrigerant flow path 15c provided in a region overlapping the pre-reaction gas flow path (36) in the stacking direction and flowing a refrigerant for adjusting the temperature of the fuel cell 1. Here, a pre-reaction oxidant gas flow path 36 for flowing the oxidant gas before flowing through the oxidant gas flow path 8 and a third refrigerant flow path 15c are provided. In this way, by configuring the humidifying unit 34 inside the laminated surface, the oxidant gas supplied to the oxidant electrode 3 can be humidified and supplied, and deterioration of the electrolyte membrane 2 due to drying can be suppressed. Moreover, since it becomes humidification after distributing to the flow path provided in each separator (6), gas distribution becomes favorable compared with humidification before distribution.

  At this time, the micro hole 37 communicating with the third refrigerant flow path 15a is provided at least in the upstream region of the pre-reaction oxidant gas flow path 36. Thereby, the oxidant gas flowing through the pre-reaction oxidant gas flow path 36 can be humidified using the refrigerant flowing through the third refrigerant flow path 15c.

  In particular, the third refrigerant flow path 15 c is provided in the downstream portion of the refrigerant path in the fuel cell 1. Thereby, since the refrigerant mixed in the oxidant gas before the reaction becomes a relatively high temperature, evaporation into the oxidant gas can be promoted.

  Next, a third embodiment will be described. Hereinafter, a description will be given centering on differences from the first embodiment.

  Here, the oxidant gas separator 6 and the fuel gas separator 7 are integrated into a single separator 59. FIG. 8A shows a plan view of the surface 59c of the separator 59 on the side in contact with the oxidant electrode 3, and FIG. 8B shows a plan view of the surface 59a on the side in contact with the fuel electrode 4. FIG. The separator 59 is made of a dense carbon material having a high thermal conductivity. However, as will be described later, a composite material that is a porous material is used for the regions that serve as the humidification / condensation heat exchange unit 54 and the condensation heat exchange unit 14. As the refrigerant, for example, an ethylene glycol aqueous solution is used.

  Similar to the second embodiment, a region A overlapping the reaction region and the condensation heat exchange unit 14 are provided. Further, a humidifying / condensing heat exchanging section 54 is provided outside the area A. Here, the region A is sandwiched between the condensation heat exchange unit 14 and the humidification / condensation heat exchange unit 54. As shown in FIG. 8, the humidifying / condensing heat exchanging portion 54 has a region overlapping the pre-reaction oxidant gas flow channel 56 provided on the surface 59c of the gas separator 59 and the pre-reaction oxidant gas flow channel 56 on the surface 59a. And a post-reaction fuel gas channel 55 provided. The pre-reaction oxidant gas flow path 56, the oxidant gas flow path 8, and the post-reaction oxidant gas flow path 16 have substantially the same flow axis, and the fuel gas flow path 9 and the post-reaction fuel gas flow path 55 are flow paths. Although the axial directions are substantially the same, this is not restrictive.

  The first to fourth oxidant gas manifolds 51a to 51d are configured in the same manner as the first to fourth oxidant gas manifolds 31a to 31d of the second embodiment. Further, as the fuel gas manifold 52, a first fuel gas manifold 52a connected to the fuel inlet pipe 26i and the upstream end of the fuel gas passage 9, a downstream end of the fuel gas passage 9, and an upstream end of the post-reaction fuel gas passage 55 And a second fuel gas manifold 52c connected to the downstream end of the post-reaction fuel gas passage 55 and the fuel outlet pipe 26o. Further, as the refrigerant manifold 53, a first refrigerant manifold 53a connected to the upstream end of the refrigerant loop 21 and the first refrigerant flow path 15a, a second refrigerant manifold 53b connected to the first refrigerant flow path 15a and an external flow path not shown, A third refrigerant manifold 53c connected to the external flow path and the refrigerant loop 21 is provided. Here, the third refrigerant manifold 53c is provided on the further outside of the humidification / condensation heat exchange unit 54, and the second refrigerant manifold 53b and the third refrigerant manifold 53c sandwich the region A and the humidification / condensation heat exchange unit 54. Configure, but not limited to this.

  The pre-reaction oxidant gas flow path 56 and the post-reaction fuel gas flow path 55 that constitute the humidification / condensation heat exchange section 54 are configured by grooves having heat exchange fins on their respective bottom surfaces. As described above, the region sandwiched between the bottom surface of the pre-reaction oxidant gas flow channel 56 and the post-reaction fuel gas flow channel 55 of the separator 59 is made of a porous material, and the pre-reaction oxidant gas flow channel 56. It is possible to move water between the fuel gas channel 55 after the reaction.

  The separator 59, the oxidant electrode 3, the electrolyte membrane 2, and the fuel electrode 4 are sequentially laminated to constitute the fuel cell 1, which is used in the same fuel cell system as in the second embodiment.

  Next, the flow state of oxidant gas, fuel gas, and refrigerant will be described.

  The refrigerant is introduced into the fuel cell 1 from the refrigerant loop 21 and distributed to the first refrigerant flow path 15a through the first refrigerant manifold 53a. After exchanging heat with the oxidant gas after reaction in the first refrigerant flow path 15a, the second refrigerant manifold 53b is circulated in the stacking direction to cool the fuel cell 1. Thereafter, the fuel cell 1 is introduced into the third refrigerant manifold 53c via an external channel (not shown), and the fuel cell 1 is cooled while flowing in the third refrigerant manifold 53c in the stacking direction.

  On the other hand, the fuel gas is supplied from the fuel inlet pipe 26i to the fuel gas flow path 9 via the first fuel gas manifold 52a and used for the power generation reaction. When flowing through the fuel gas passage 9, part of the water contained in the electrolyte membrane 2 in the fuel gas evaporates. As a result, the fuel gas having a relatively high temperature and high humidity is introduced into the post-reaction fuel gas passage 55 constituting the humidification / condensation heat exchanging portion 54 via the second fuel gas manifold 52b. Further, a relatively low temperature and low humidity oxidant gas is introduced from the oxidant inlet pipe 25i into the pre-reaction oxidant gas flow path 56 constituting the humidification / condensation heat exchange section 54 via the first oxidant gas manifold 51a. Is done.

  In the humidification / condensation heat exchanging section 54, water and heat are transferred through the electrolyte membrane 2 held between the opening sides of the grooves constituting the pre-reaction oxidant gas flow path 56 and the post-reaction fuel gas flow path 55, respectively. Arise. Further, movement of water and heat occurs through the porous material constituting the bottom surfaces of the pre-reaction oxidant gas flow channel 56 and the post-reaction fuel gas flow channel 55. Water moves from the relatively high-humidity fuel gas in the post-reaction fuel gas channel 55 to the relatively low-humidity oxidant gas in the pre-reaction oxidant gas channel 56. The driving force at that time is a water vapor partial pressure difference between the fuel gas and the oxidant gas. Further, heat is transferred from the relatively high temperature fuel gas in the post-reaction fuel gas flow channel 55 to the relatively low temperature oxidant gas in the pre-reaction oxidant gas flow channel 56. Along with this heat transfer, the oxidant gas is heated and the condensation in the fuel gas is promoted.

  After the water and heat are exchanged in this way, the fuel gas is discharged from the third fuel gas manifold 52c to the fuel outlet pipe 56o. On the other hand, the humidified oxidant gas is distributed to the oxidant gas flow path 8 through the second oxidant gas manifold 51b, and the third oxidant manifold 51c is passed through the third oxidant manifold 51c in a state of high temperature and high humidity accompanying the reaction. Then, it is introduced into the post-reaction oxidant gas flow path 16 constituting the condensation heat exchange section 14. Here, heat exchange with the refrigerant flowing through the first refrigerant flow path 15a formed on the back surface 59a is performed, and water in the oxidant gas after the reaction is condensed. As described above, since the region constituting the condensation heat exchanging portion 14 of the separator 59 is made of a porous material, water existing as droplets in the post-reaction oxidant gas flow channel 16 adjoins through the bottom surface. The first refrigerant flow path 15a is recovered. A part of the water is discharged together with the oxidant gas to the oxidant outlet pipe 25 o through the fourth oxidant gas manifold 51 d and is collected by the buffer unit 27.

  Since a part of the separator 59 is a porous material, it is preferable that the part is pre-hydrated when the fuel cell 1 is operated.

  In this way, in the humidification / condensation heat exchange section 54, water and heat are exchanged between the unreacted gas (oxidant gas before reaction) and the already-reacted gas (fuel gas after reaction). Water and heat exchange are performed via at least one of the porous material constituting the separator 59 or the electrolyte membrane 2. At this time, since moisture is contained in the porous material, a gas wet-sealing action is ensured.

  Next, the effect of this embodiment will be described. Only the effects different from those of the first and second embodiments will be described below.

  One of the oxidant gas or fuel gas before being introduced into the reaction gas channel 8 or 9 is humidified and contained in the other of the oxidant gas or fuel gas after flowing through the reaction gas channel 8 or 9 A humidifying / condensing heat exchanging unit 54 for condensing water. Here, the humidifying / condensing heat exchanging unit 54 that humidifies the oxidizing gas before being introduced into the oxidizing gas channel 8 and condenses the water contained in the fuel gas after flowing through the fuel gas channel 9 is provided. Prepare. As the humidification / condensation heat exchange section 54, the pre-reaction oxidant gas flow channel 56 for flowing the oxidant gas before flowing through the oxidant gas flow channel 8 and the fuel gas after flowing through the fuel gas flow channel 9 are circulated. And a post-reaction fuel gas channel 55. In the stacking direction, at least one of the electrolyte membrane 2 and the porous material is used as a partition wall that separates the pre-reaction oxidant gas flow channel 56 and the post-reaction fuel gas flow channel 55. Here, the electrolyte membrane 2 and a porous material constituting a part of the separator 59 are used as the partition walls. Thereby, in the humidification and condensation heat exchange part 54, while humidifying the oxidizing gas before reaction, the water contained in the fuel gas after reaction can be condensed.

  The area | region which provides the condensation heat exchange part 14 at least of the separator 59 is comprised with a porous material. Further, at least a region of the separator 59 where the humidification / condensation heat exchange unit 54 is provided is formed of a porous material. Thereby, when a driving force is generated, the condensed water generated by the condensation heat exchange can move inside the porous material.

  Furthermore, an aqueous solution containing an antifreeze component is used as a refrigerant. Thereby, freezing in an environment below the freezing point can be prevented.

  Next, a fourth embodiment will be described. Hereinafter, a description will be given centering on differences from the second embodiment.

  The oxidant gas separator 6 and the fuel gas separator 7 are integrated to form one separator 69. FIG. 9A shows a plan view of the surface 59c of the separator 69 on the side in contact with the oxidant electrode 3, and FIG. 9B shows a plan view of the surface 69a on the side in contact with the fuel electrode 4. As shown in FIG. The separator 69 is made of a hydrophilic porous carbon resin composite material. For example, the average pore diameter of the porous material is about 50 μm. The oxidant is introduced into the fuel cell 1 in a pressurized state. Pure water is used as the refrigerant. As will be described later, the refrigerant is adjusted so as to be at least negative with respect to the atmospheric pressure in the fuel cell 1.

  Similarly to the second embodiment, the region A and the condensation heat exchange unit 14 are configured. Moreover, the humidification part 64 is comprised from the pre-reaction oxidant gas flow path 66 and the 3rd refrigerant | coolant flow path 15c similarly to 2nd Embodiment. However, the pre-reaction oxidant gas flow channel 66 is not provided with the minute holes 37 and the chevron-shaped ribs 38, but is constituted by a groove having a heat exchange fin on the bottom surface.

  The oxidant gas manifold 31, the fuel gas manifold 32, and the refrigerant manifold 33 are the same as those in the second embodiment. The separator 69, the oxidant electrode 3, the electrolyte membrane 2, and the fuel electrode 4 are sequentially laminated to constitute the fuel cell 1. When the fuel cell 1 is operated, it is preferable to pre-hydrate the porous material.

  A fuel cell system using such a fuel cell 1 is shown in FIG.

  A refrigerant loop 71 for introducing a refrigerant into the fuel cell 1 is provided. Furthermore, a pump 72 serving as a power source for circulating the refrigerant, a radiator 73 for radiating the refrigerant, and a refrigerant accumulating unit 74 for accumulating the refrigerant are provided. The pump 72 is disposed on the downstream side of the fuel cell 1 in the refrigerant loop 71. In addition, the refrigerant accumulation unit 74 is disposed between the discharge port of the pump 72 and the inlet of the fuel cell 1. Furthermore, the upper part of the refrigerant | coolant storage part 74 is comprised so that air | atmosphere is open | released. Thereby, the refrigerant | coolant loop 71 turns into a loop of a negative pressure with respect to substantially atmospheric pressure. In particular, the fuel cell 1 has a negative pressure.

  The refrigerant accumulating portion 74 includes a U-shaped trap-shaped discharge line 79 for discharging a part of the refrigerant accumulated therein. Further, an oxidant inlet pipe 75i for introducing the oxidant gas and the fuel gas into the fuel cell 1, a fuel inlet pipe 76i, an oxidant outlet pipe 75o for discharging from the fuel cell 1, and a fuel outlet pipe 76o are provided. On the side of the oxidant outlet pipe 75o and the fuel outlet pipe 76o, a throttle 80 is provided as means for pressurizing the oxidant gas and fuel gas in the fuel cell 1. Here, as will be described later, since the condensed water is recovered in the refrigerant system inside the fuel cell 1, the buffer unit 27 described in the first embodiment and the like is omitted.

  Next, differences from the second embodiment regarding the flow of oxidant gas, fuel gas, and refrigerant will be described.

  In the humidification unit 64, the oxidant gas introduced from the outside of the fuel cell 1 in a low temperature and low humidity state is introduced into the pre-reaction oxidant gas flow channel 66 through the first oxidant gas manifold 31a. In addition, the refrigerant having a relatively high temperature through heat exchange when passing through the second refrigerant manifold 33b and the third refrigerant manifold 33c is introduced into the third refrigerant flow path 15c. In the humidifying section 64, using the concentration difference as a driving force, a part of the refrigerant moves to the pre-reaction oxidant gas flow channel 66 side through the inside of the porous material, and a part thereof evaporates into the oxidant gas. At this time, since the relatively high-temperature refrigerant moves into the pre-reaction oxidant gas flow channel 66, evaporation into the oxidant gas is promoted. Further, since the oxidant gas before being introduced into the reaction region is heated, it becomes easy to maintain an appropriate reaction temperature when introduced into the reaction region.

  On the other hand, in the condensation heat exchanging unit 14, a relatively low-temperature refrigerant is introduced into the first refrigerant flow path 15a from the outside of the fuel cell 1 via the first refrigerant manifold 33a. Further, the oxidant gas that has become high temperature and high humidity by the power generation reaction is introduced into the post-reaction oxidant gas flow path 16 through the third oxidant gas manifold 31c. The refrigerant before the high temperature and the refrigerant after the reaction exchange heat, thereby condensing water in the oxidant gas. Here, as described above, the refrigerant has a negative pressure relative to the atmospheric pressure at least in the fuel cell 1. Therefore, the water condensed in the oxidant gas flow path 16 after the reaction moves in the porous material and is collected by the refrigerant system using the pressure difference between the oxidant gas and the refrigerant as a driving force. Further, since the temperature of the refrigerant is increased by the oxidant gas, it is possible to avoid locally cooling the reaction region.

  Thus, a porous material is used for the condensation heat exchanging unit 14 and the humidifying unit 64, and the pressure of the refrigerant is made lower than the reaction gas pressure. In the condensation heat exchanging unit 14, the condensed water is selectively absorbed by the refrigerant through the porous material. In the humidifying section 66, the refrigerant smoothly moves inside the porous material according to the concentration difference caused by evaporation. Moreover, in the pre-reaction oxidant gas flow channel 66, since the refrigerant flows toward the back surface 69a side of the porous material, drying of the oxidant gas supplied to the reaction region is prevented.

  Moreover, since the average pore diameter of the porous material is 0.5 μm, it is possible to ensure the wet seal action of the gas by the refrigerant inside the porous material. FIG. 11 shows the relationship between the average pore diameter and bubble pressure. The bubble pressure is a pressure at which the force that the water contained in the pores stays in the pores due to surface tension is broken by the pressure of the gas (pressure difference between the gas and water). By setting the average pore size to 0.5 μm or less, the above bubble pressure is improved and the wet seal function works even if the differential pressure between the refrigerant below atmospheric pressure and the pressurized gas is 80 kPa.

  Next, the effect of this embodiment will be described. Hereinafter, only effects different from the effects of the first to third embodiments will be described.

  The area | region which provides the condensation heat exchange part 14 at least of the separator 69 is comprised with a porous material. Thereby, the condensed water generated by the condensation heat exchange can move inside the porous material. Moreover, the area | region which provides the humidification part 64 at least with the separator 69 is comprised with a porous material. Thereby, the water used for humidification can be moved inside the porous material.

  Here, the average pore diameter of the porous material is 0.5 μm or less. This makes it possible to prevent gas leaks penetrating through the porous material volume with the wet seal action due to the surface tension of the refrigerant, even under conditions where the differential pressure between the refrigerant and the reaction gas is large, improving durability against pressure changes. can do.

  Furthermore, the refrigerant | coolant pressure adjustment means which adjusts the pressure of the refrigerant | coolant which distribute | circulates the 1st refrigerant | coolant flow path 15a is provided. Here, a pump 71 is provided on the downstream side of the fuel cell 1, and a refrigerant storage unit 74 whose upper part is opened to the atmosphere is provided. The pressure of the refrigerant flowing through the first refrigerant channel 15a is made smaller than the oxidant gas pressure in the post-reaction oxidant gas channel 16. Thereby, condensed water can move to the inside of a porous material by a pressure difference.

  In the embodiment described above, the oxidant gas path and the fuel gas path may be interchanged in the fuel cell 1. In this case, for example, the condensation heat exchange unit 14 condenses water in the fuel gas after the reaction.

  Thus, the present invention is not limited to the best mode for carrying out the invention, and various modifications can be made within the scope of the technical idea described in the claims. Not too long.

  The present invention can be applied to a polymer electrolyte fuel cell and a fuel cell system using the same. In particular, the present invention can be applied to a fuel cell system used as a power source for a mobile body or the like that is required to be compact.

It is a schematic block diagram of the fuel cell used for 1st Embodiment. It is a top view of the oxidant gas separator used for a 1st embodiment. It is a top view of the fuel gas separator used for a 1st embodiment. It is a schematic block diagram of the fuel cell system used for 1st Embodiment. It is a top view of the oxidizing agent gas separator used for a 2nd embodiment. It is a top view of the fuel gas separator used for a 2nd embodiment. It is a schematic block diagram of the fuel cell system used for 2nd Embodiment. It is a top view of the separator used for a 3rd embodiment. It is a top view of the separator used for a 4th embodiment. It is a schematic block diagram of the fuel cell system used for 4th Embodiment. It is a relationship figure of an average porosity and bubble pressure.

Explanation of symbols

1 Fuel Cell 2 Electrolyte Membrane 3 Oxidant Electrode (Cathode Electrode Layer)
4 Fuel electrode (anode electrode layer)
6 Oxidant gas separator (separator)
7 Fuel gas separator (separator)
8 Oxidant gas channel (reactive gas channel)
9 Fuel gas channel (reactive gas channel)
14 Condensation heat exchanger 15 Refrigerant flow path 15a First refrigerant flow path 15c Third refrigerant flow path (second refrigerant flow path)
16 Post-reaction oxidant gas flow path (post-reaction gas flow path)
34 Humidification section 54 Humidification and condensation heat exchange section 55 Post-reaction fuel gas flow path (post-reaction gas flow path)
56 Pre-reaction oxidant gas flow path (pre-reaction gas flow path)
64 Humidifying section 66 Pre-reaction oxidant gas flow path 72 Pump (refrigerant pressure adjusting means)
74 Refrigerant accumulation part

Claims (13)

A cathode electrode layer provided on both main surfaces of the electrolyte membrane, an anode electrode layer, and
A reaction gas flow path for flowing an oxidant gas or a fuel gas between each of the electrode layers, and a separator having a laminate surface larger than the electrode layer,
A solid polymer comprising a condensation heat exchanging portion having at least one of an oxidant gas and a fuel gas after flowing through the reaction gas flow path as a heat source in a region other than the electrode layer on the separator lamination surface Type fuel cell. As the condensation heat exchange section,
A post-reaction gas flow path for flowing the reaction gas after flow of the reaction gas flow path provided between the electrode layer and the separator;
2. A solid polymer fuel according to claim 1, further comprising: a first refrigerant channel provided in a region overlapping with the post-reaction gas channel in a stacking direction and circulating a refrigerant for adjusting a temperature of the fuel cell. battery. A humidifying unit for humidifying at least one of the oxidant gas and the fuel gas before being introduced into the electrode layer;
Furthermore, the reforming includes
A pre-reaction gas flow path for flowing at least one of an oxidant gas or a fuel gas before flowing through the reaction gas flow path provided between the electrode layer and the separator;
2. A solid polymer fuel according to claim 1, further comprising: a second refrigerant channel provided in a region overlapping with the pre-reaction gas channel in a stacking direction and circulating a refrigerant for adjusting a temperature of the fuel cell. battery. One of the oxidant gas or fuel gas before being introduced into the reaction gas flow path is humidified, and water contained in the other of the oxidant gas or fuel gas after flowing through the reaction gas flow path is condensed. A humidifying and condensing heat exchanger
Furthermore, in the humidification and condensation heat exchange part,
A pre-reaction gas flow path that circulates one of oxidant gas or fuel gas before flowing through the reaction gas flow path provided between the electrode layer and the separator;
A post-reaction gas flow channel that circulates the other of the oxidant gas or the fuel gas after flowing through the reaction gas flow channel,
2. The polymer electrolyte fuel cell according to claim 1, wherein at least one of the electrolyte membrane and the porous material is used as a partition wall separating the pre-reaction gas flow channel and the post-reaction gas flow channel in the stacking direction.   The polymer electrolyte fuel cell according to claim 2, wherein at least the region of the separator in which the condensation heat exchange part is provided is formed of a porous material.   The polymer electrolyte fuel cell according to claim 2, wherein the first refrigerant flow path is provided in an upstream portion of a refrigerant path in the fuel cell.   4. The polymer electrolyte fuel cell according to claim 3, wherein a micropore communicating with the second refrigerant channel is provided in at least an upstream region of the pre-reaction gas channel.   The polymer electrolyte fuel cell according to claim 3, wherein at least the region of the separator where the humidifying portion is provided is formed of a porous material.   The polymer electrolyte fuel cell according to claim 3, wherein the second refrigerant flow path is provided in a downstream portion of a refrigerant path in the fuel cell.   4. The polymer electrolyte fuel cell according to 2 or 3, wherein the refrigerant is an aqueous solution containing an antifreeze component.   9. The polymer electrolyte fuel cell according to claim 4, wherein an average pore diameter of the porous material is 0.5 μm or less.   A fuel cell system using the polymer electrolyte fuel cell according to any one of claims 1 to 11. A fuel cell system using the solid polymer fuel cell according to claim 5,
Comprising refrigerant pressure adjusting means for adjusting the pressure of the refrigerant flowing through the first refrigerant flow path;
A fuel cell system, wherein a pressure of a refrigerant flowing through the first refrigerant flow path is made smaller than a reaction gas pressure in the post-reaction gas flow path.

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