JP5065601B2 - Fuel cell stack - Google Patents

Description

  The present invention relates to an internal manifold type fuel cell stack.

  A fuel cell stack used in a fuel cell vehicle or the like is generally configured by laminating a plurality of single cells each having an anode electrode and a cathode electrode disposed on both surfaces of an electrolyte membrane made of a solid polymer. In this type of fuel cell stack, a laminated body composed of a plurality of single cells is provided with a communication hole for supplying air (oxygen) to each cathode electrode and a communication hole for supplying hydrogen to each anode electrode. An internal manifold type fuel cell stack is generally employed. In this type of fuel cell stack, in order to improve ion conductivity by the electrolyte membrane, air supplied to the cathode electrode and hydrogen supplied to the anode electrode are humidified.

  However, when the above-described fuel cell stack is used in a low-temperature environment that is below freezing point, when the reaction gas is introduced into the communication hole formed in the fuel cell stack, the reaction gas is cooled and condensation occurs. There is a problem in that water droplets flow into each electrode of the cathode electrode and the anode electrode through the communication hole, and the supply of the reaction gas to the electrode is hindered to reduce the power generation performance.

Therefore, in order to prevent water droplets from flowing into the electrode surface, Patent Document 1 proposes a technique of draining water via a bypass channel that bypasses the fuel cell stack when water droplets are generated. Patent Document 2 proposes a technique of providing a drain device for collecting and discharging water droplets in the middle of a hydrogen gas path on the anode side.
Japanese Patent Laying-Open No. 2003-346869 (FIG. 9) JP 2002-313403 A (FIG. 1)

  However, in the fuel cell stack described in Patent Document 1, since the reaction gas supplied to the stack together with water droplets is also bypassed, there is a problem that a reaction gas that cannot be used for power generation is generated and power generation efficiency deteriorates. In addition, the fuel cell stack described in Patent Document 2 requires a drainage mechanism as shown in the drain device, which leads to an increase in the size of the fuel cell system, and it is necessary to periodically discharge the accumulated water droplets. In this case, unused hydrogen is also discharged at the same time, and there is a problem that power generation efficiency deteriorates.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a fuel cell stack capable of stabilizing power generation by preventing water droplets from flowing into the electrode surface of each single cell. .

The present invention includes a laminate in which a plurality of unit cells each having a membrane electrode assembly in which a pair of electrodes are arranged on both surfaces of an electrolyte membrane are sandwiched by a pair of separators and are laminated in the thickness direction. A through-side communication hole for supplying the reaction gas to the electrode of each single cell through the separator in the thickness direction, and a discharge-side communication hole for discharging off-gas from each single cell; an internal manifold type fuel cell stack which is provided, in front Symbol supply passage is provided supply-side heating section, the separator, the reaction gas circulating the reaction gas in a region corresponding to the electrode And a supply-side communication path that communicates the reaction gas flow path with the supply-side communication hole, and the supply-side heating means includes the supply-side communication path side of the inner wall that forms the supply-side communication hole. The inner wall of And having a shape covering the Ku inner wall. The supply side heating means corresponds to the heaters 10, 20, 10A, 20A of the embodiments described later. The supply side communication paths correspond to the communication paths 14g and 15g in the embodiments described later.

  According to the present invention, since the heating means is provided at least in the supply side communication hole, the heating side heats the inside of the supply side communication hole when there is a possibility that water droplets are generated due to condensation in the supply side communication hole. By doing so, dew condensation can be prevented, and water droplets can be prevented from flowing into the electrode surface of each single cell.

Further, the supply side communication path has a plurality of bridges arranged at intervals in the width direction,
The supply side heating means is arranged at a position corresponding to the bridge on the inner wall on the supply side communication path side.
The separator has a quadrangular shape, and the supply side communication hole is arranged at a corner of the separator.
Further, a communication hole through which a cooling medium flows is disposed adjacent to the supply side communication hole.
In addition, the inner wall of the supply-side communication hole is formed to be uneven by laminating the single cells, and the supply-side heating means has an outer surface configured along the unevenness of the inner wall.
The discharge-side communication hole is provided with a discharge-side heating means, and the separator includes a discharge-side communication path that connects the reaction gas flow passage and the discharge-side communication hole, and the discharge-side heating means The inner wall constituting the discharge-side communication hole has a shape that covers the inner wall excluding the inner wall on the discharge-side communication path side. The discharge side communication path corresponds to the communication paths 14i and 15i of the embodiment described later.
And a first temperature sensor for detecting a temperature of the reaction gas charged into the stacked body, and a second temperature sensor for detecting a surface temperature of the stacked body, wherein the temperature of the reactive gas and the surface temperature are provided. And a control device for controlling the supply-side heating means. The first temperature sensor corresponds to the temperature sensors 61 and 62 in the embodiment described later, and the second temperature sensor corresponds to the temperature sensor 60 in the embodiment described later.
Moreover, it is preferable that the said heating means is a sheet form. Thereby, since the unevenness | corrugation of the inner wall of the communicating hole formed by laminating | stacking a several single cell can be eliminated, it becomes possible to reduce the pressure loss of a reactive gas. As a result, the variation in the supply of the reaction gas between the single cells can be reduced, and the variation in the cell voltage can be reduced.

  According to the present invention, it is possible to prevent water droplets from flowing into the electrode surface of each single cell and to stabilize power generation.

  1A and 1B show a fuel cell stack of the present embodiment, in which FIG. 1A is an exploded perspective view, FIG. 2B is a side view, FIG. 2 is an exploded perspective view showing a single cell stack structure, and FIG. (B) is a plan view showing the cathode-side separator, FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 (b), (a) is a state before attaching the heating means, ( b) is a state after the heating means is attached, and FIGS. 5A to 5C are cross-sectional views showing a method for attaching the heating means.

  As shown in FIGS. 1 (a) and 1 (b), the fuel cell stack FC of this embodiment is an internal manifold type fuel cell stack, in which a plurality of single cells 1 are stacked, an end plate, and an end plate. 3, 4 and heaters 10 and 20 as heating means.

  As shown in FIG. 2, the single cell 1 includes an ionic conductive solid polymer electrolyte membrane (hereinafter abbreviated as an electrolyte membrane) 11 on one side, an anode electrode 12 having a catalyst, and the other side. Further, a membrane electrode assembly (MEA) sandwiched between cathode electrodes 13 provided with a catalyst is further sandwiched between a pair of conductive separators 14 and 15. A stack of the single cells 1 corresponds to the stacked body 2 (see FIG. 1). The electrolyte membrane 11 is formed so as to protrude laterally (in the left-right direction) from the edges of the anode electrode 12 and the cathode electrode 13, and through holes 11a, 11b, 11c is formed. Further, through holes 11d, 11e, and 11f are formed in the upper, middle, and lower stages on the front side in FIG.

  The separator 14 is provided on the side facing the anode electrode 12, and a comb-shaped anode in which hydrogen as a reaction gas flows in a region corresponding to the anode electrode 12 on a surface facing the anode electrode (electrode) 12. A gas flow passage 14S is formed. Further, the separator 14 is formed with through holes 14a, 14b, and 14c at the upper, middle, and lower stages on the back side in FIG. Further, through holes 14d, 14e, and 14f are formed in the upper, middle, and lower stages on the front side in FIG. The separator 14 is formed with a communication path 14g for communicating the through hole 14a and the anode gas flow path 14S, and a communication path 14i for communicating the anode gas flow path 14S and the through hole 14f. A plurality of bridges 14h and 14j formed of an elastic member such as rubber are arranged at 14g and 14i at intervals in the width direction.

  The separator 15 is provided on the side facing the cathode electrode 13, and is formed on the surface facing the cathode electrode 13 as a reactive gas in a region corresponding to the cathode electrode (electrode) 13 as shown in FIG. A comb-shaped cathode gas flow passage 15S through which air (oxygen) flows is formed. The separator 15 is formed with a communication path 15g for communicating the through hole 15d and the cathode gas flow path 15S, and a communication path 15i for communicating the cathode gas flow path 15S and the through hole 15c. A plurality of bridges 15h and 15j formed of an elastic member such as rubber are arranged in the communication paths 15g and 15i with a gap in the width direction. Further, as shown in FIG. 2, a cooling medium flow passage 16S through which the cooling medium flows is formed in a comb-tooth shape on the surface of the separator 15 opposite to the cathode gas flow passage 15S. This cooling medium cools the fuel cell stack FC by flowing through the cooling medium flow passage 16S. Further, the separator 15 has through holes 15a, 15b, and 15c formed at the upper, middle, and lower stages on the back side of FIG. 2, and through holes 15d, 15e, and 15f are formed at the upper, middle, and lower stages on the front side of the sheet. Yes. The separator 15 is formed with a communication path 16a for communicating the through hole 15b and the cooling medium flow path 16S, and a communication path 16c for communicating the cooling medium flow path 16S and the through hole 15e. A plurality of bridges 16b and 16d similar to the above are arranged on 16a and 16c.

  The single cell 1 is provided with seal members 17 and 18 between the MEA and the separator 14 and between the MEA and the separator 15, respectively. Further, a seal member 19 is provided between the separator 15 and the separator 14 of the single cell 1 adjacent thereto. Note that any of the seal members 17, 18, and 19 is formed of an elastic member such as rubber.

  The seal member 17 includes a seal portion 17a that covers and seals the through hole 14a, the communication path 14g, the cathode gas flow path 14S, the communication path 14i, and the through hole 14f, and a seal portion that covers and seals the periphery of the through hole 14b. 17b, a seal portion 17c that covers and seals the periphery of the through hole 14c, a seal portion 17d that covers and seals the periphery of the through hole 14d, and a seal portion 17e that covers and seals the periphery of the through hole 14e.

  The seal member 18 includes a seal portion 18a that covers and seals the periphery of the through hole 15a, a seal portion 18b that covers and seals the periphery of the through hole 15b, a through hole 15d, a communication path 15g, a cathode gas flow path 15S, and a communication path. 15i and a seal portion 18d that covers and seals the periphery of the through hole 15c, a seal portion 18e that covers and seals the periphery of the through hole 15e, and a seal portion 18f that covers and seals the periphery of the through hole 15f.

  The sealing member 19 includes a sealing portion 19a for covering and sealing the periphery of the through hole 15a, and a sealing portion for covering and sealing the periphery of the through hole 15b, the communication path 16a, the cooling medium flow path 16S, the communication path 16c, and the through hole 15e. 19b, a seal portion 19c that covers and seals the periphery of the through hole 15c, a seal portion 19d that covers and seals the periphery of the through hole 15d, and a seal portion 19f that covers and seals the periphery of the through hole 15f.

  In the single cell 1 described above, hydrogen is supplied while flowing through the supply-side communication hole R1 constituted by the seal portion 19a, the through-hole 15a, the seal portion 18a, the through-hole 11a, the seal portion 17a, and the through-hole 14a. (Anode off gas) is discharged while flowing through the discharge side communication hole R3 constituted by the through hole 14f, the seal part 17a, the through hole 11f, the seal part 18f, the through hole 15f, and the seal part 19f. . The air is supplied while flowing through the supply side communication hole R2 constituted by the seal portion 19d, the through hole 15d, the seal portion 18d, the through hole 11d, the seal portion 17d, and the through hole 14d, and off gas (cathode off gas) is supplied. The through-hole 14c, the seal portion 17c, the through-hole 11c, the seal portion 18d, the through-hole 15c, and the seal portion 19c are discharged while flowing through the discharge-side communication hole R4. Further, the cooling medium is supplied through the seal portion 19b, the through hole 15b, the seal portion 18b, the through hole 11b, the seal portion 17b, and the through hole 14b, and the through hole 14e, the seal portion 17e, the through hole 11e, and the seal portion. 18e, the through hole 15e, and the seal portion 19b are discharged.

  In addition, as shown to Fig.4 (a), seal part 17a, 18a, 19a is located outside opening edge part 14a1, 15a1 of through-hole 14a, 15a, and seal part 17d, 18d, 19d is located outside the opening edge portions 14d1 and 15d1 of the through holes 14d and 15d.

  Moreover, in this embodiment, the supply side communication hole R1 (anode side) of the present invention is configured by the seal portion 19a, the through hole 15a, the seal portion 18a, the through hole 11a, the seal portion 17a, the through hole 14a,. ing. Further, the supply side communication hole R2 (cathode side) of the present invention is configured by the seal portion 19d, the through hole 15d, the seal portion 18d, the through hole 11d, the seal portion 17d, the through hole 14d,. Further, in this embodiment, the discharge side communication hole R3 (see FIG. 3) on the anode side of the present invention is provided by the seal portion 19f, the through hole 15f, the seal portion 18f, the through hole 11f, the seal portion 17a, the through hole 14f,. ) Is configured. Further, the cathode side discharge side communication hole R4 (see FIG. 3) of the present invention is constituted by the seal portion 19c, the through hole 15c, the seal portion 18d, the through hole 11c, the seal portion 17c, and the through hole 14c.

  As shown in FIG. 1 (a), the end plate 3 has a metal plate laminated on one end face of the laminated body 2 of the single cell 1, and the through holes 15a, 15b, Through holes 3a, 3b, 3c, 3d, 3e, 3f are formed at positions corresponding to 15c, 15d, 15e, 15f. The end plate 4 has a metal plate laminated on the other end face of the laminate 2. Note that the end plate 3 and the end plate 4 are connected by a member (not shown) so that the laminated body 2 is held with no play when a predetermined load is applied thereto. Further, an insulator (insulator, not shown in FIG. 1) 5 is provided between the end plate 4 and the laminate 2 as shown in FIG. An electrode 6 for taking out electricity is provided.

  In the fuel cell stack FC described above, as shown in FIG. 2, when hydrogen is supplied from the through hole 3a (see FIG. 1), this hydrogen is passed through the through hole 15a, the seal portion 18a, the through hole 11a, and the seal portion 17a. The anode gas flow path 14S is supplied to the anode electrode 12 through the communication path 14g. The air supplied from the through hole 3d (see FIG. 1) is supplied to the cathode electrode 13 from the cathode gas flow passage 15S (see FIG. 3) through the through hole 15d and the communication path 15g. In the anode electrode 12, protons (hydrogen ions) and electrons are decomposed by the action of the catalyst, the protons pass through the electrolyte membrane 11 to the cathode electrode 13, and the electrons move to the cathode electrode 13 through an external load. Electrons generated at the anode electrode 12 are taken out from the separator 14 and the electrode 6 and return to the cathode electrode 13 from the electrode 6 through an electrode (not shown) on the end plate 4 side via an external load. On the other hand, in the cathode electrode 13, water is generated by the reaction of protons that have passed through the electrolyte membrane 11, oxygen in the air, and electrons from an external load by the action of the catalyst.

  The heater 10 has a sheet shape, and can be formed, for example, by sandwiching an electric resistor between sheet substrates made of synthetic resin facing each other. The heater 10 includes a surface 10a that covers the inner wall facing the outside of the supply side communication hole R1 on the anode side, a surface 10b that covers the inner wall facing upward, and a surface 10c that covers the inner wall facing downward. These are arranged so that the shape in a plan view in the stacking direction becomes a U-shape. The heater 20 is also formed in the same manner, and includes a surface 20a that covers the inner wall facing the outside of the supply side communication hole R2 on the cathode side, a surface 20b that covers the inner wall facing upward, and a surface 20c that covers the inner wall facing downward. It is comprised. The heaters 10 and 20 are formed with a length that can cover one end to the other end of the supply side communication holes R1 and R2 formed in the laminate 2.

  As a means for holding the heater 10 in the supply side communication hole R1, as shown in FIG. 5A, an extension 10d extending in the stacking direction is integrally formed at the end of the heater 10, and this extension is performed. The protruding portion 10 d may be held between the end plate 4 and the insulator 5. The position where the extending portion 10d is sandwiched is not limited between the end plate 4 and the insulator 5, but can be changed as appropriate according to the laminated structure of the end plate 4, the insulator 5, and the electrode 6. As other holding means, as shown in FIG. 5B, an adhesive layer 7 is provided between the heater 10 and the supply side communication hole R1, and the heater 10 is fixed in the supply side communication hole R1. You may do it. Alternatively, as shown in FIG. 5C, the rear surface of the heater 10 is formed with a convex portion 8 having a shape that follows the concave portion m (see FIG. 4B) formed in the supply side communication hole R1. The convex portion 8 may be fitted and held in the concave portion m of the supply side communication hole R1.

  Although only one end of the heater 10 has been described, the other, that is, the end plate 3 side can be similarly held. 5 (b) and 5 (c), only the surface 10a of the heater 10 has been described, but the other surfaces 10b and 10c are similarly supplied via the adhesive layer 7 and the convex portion 8 to the supply side communication hole R1. Is held in. Although only one heater 10 has been described, the other heater 20 can be configured in the same manner. Moreover, you may combine the means of Fig.5 (a)-(c).

  As shown in FIG. 6, the fuel cell system F1 equipped with the fuel cell stack FC of the present embodiment includes an anode system 30, a cathode system 40, a control device 50, temperature sensors 60, 61, 62, an ignition 70, and the like. ing. In the following description, the case where the vehicle is mounted on a vehicle such as a fuel cell vehicle will be described as an example.

  The anode system 30 includes an anode gas pipe 31, an anode off-gas pipe 32, a high-pressure hydrogen tank 33, a shut-off valve 34, a humidifier 35, and the like. The anode gas pipe 31 has one end connected to the high-pressure hydrogen tank 33 and the other end connected to the supply side communication hole R1 of the fuel cell stack FC. One end of the anode off-gas pipe 32 is connected to the discharge side communication hole R3 of the fuel cell stack FC, and the other end is connected to a dilution device (not shown). The high-pressure hydrogen tank 33 is filled with high-purity hydrogen at a high pressure of 35 MPa, for example. The shut-off valve 34 is, for example, an electromagnetically operated type, and is provided downstream of the high-pressure hydrogen tank 33. The humidifier 35 is provided with a water permeable membrane and humidifies hydrogen supplied to the fuel cell stack FC, and is configured by connecting an anode gas pipe 31 and an anode offgas pipe 32.

  The cathode system 40 includes a cathode gas pipe 41, a cathode offgas pipe 42, an air compressor 43, a humidifier 44, and the like. The cathode gas pipe 41 has one end connected to the air compressor 43 and the other end connected to the supply side communication hole R2 of the fuel cell stack FC. One end of the cathode offgas pipe 42 is connected to the discharge side communication hole R4 of the fuel cell stack FC, and the other end is connected to a diluting device (not shown). The air compressor 43 includes a supercharger and the like. The humidifier 44 is provided with a water permeable membrane and humidifies the air supplied to the fuel cell stack FC, and is configured by connecting a cathode gas pipe 41 and a cathode offgas pipe 42.

  Note that water generated at the cathode electrode 13 is used as a humidifying source for humidifying air, and water generated at the cathode electrode 13 is used as an humidifying source for humidifying hydrogen via the electrolyte membrane 10. Water that has permeated through the electrode 12 is used.

  The control device 50 includes a microcomputer, ROM, RAM, peripheral circuit, input / output interface, and the like (not shown), and includes heaters 10 and 20, a shutoff valve 34, an air compressor 43, temperature sensors 60, 61 and 62, an ignition (IG) ) 70. The temperature sensor 60 detects the temperature of the fuel cell stack FC. For example, the temperature sensor 60 detects the surface temperature of the fuel cell stack FC or the inner wall temperatures of the supply side communication holes R1 and R2. In addition, the inner wall temperature of the fuel cell stack FC is a position indicated by a point P in FIG. 4B, that is, between the recess m (see FIG. 4A) of the supply side communication hole R1 and the surface 10a of the heater 10. It can be detected by arranging a rod-shaped temperature sensor in the space. The temperature sensor 61 is provided in the vicinity of the inlet on the anode side of the fuel cell stack FC, and detects the temperature of hydrogen charged into the fuel cell stack FC. The temperature sensor 62 is provided in the vicinity of the cathode side inlet of the fuel cell stack FC, and detects the temperature of the air charged into the fuel cell stack FC. In this control device 50, ON / OFF switching of the heaters 10, 20, opening / closing of the shut-off valve 34, and rotation speed information of the air compressor 43 are output, temperature information of the fuel cell stack FC is output from the temperature sensor 60, and temperature sensor 61 The hydrogen temperature information, the air temperature information, and the ON / OFF signal of the ignition 70 are acquired from the temperature sensor 62.

Next, the operation of the fuel cell stack FC of the present embodiment will be described in a state including the control of the fuel cell system F1.
First, when the ignition (IG) 70 of the vehicle is turned on (step S1), the control device 50 starts the system (step S2). In this system start-up, the shutoff valve 34 is opened to supply hydrogen humidified by the humidifier 35 from the high-pressure hydrogen tank 33 to the anode electrode 12 of the fuel cell stack FC, and the air compressor 43 is driven. The outside air is taken in and the air (oxygen) humidified by the humidifier 44 is supplied to the cathode electrode 13 of the fuel cell stack FC. At this time, the humidified hydrogen is supplied from the through hole 3a formed in the end plate 3, and the humidified air is supplied from the through hole 3d.

  In step S3, the control device 50 determines whether the hydrogen temperature (input gas temperature) T1 and the air temperature T2 are equal to or higher than the surface temperature T of the fuel cell stack FC. If it is determined in step S3 that the hydrogen temperature T1 and the air temperature T2 are equal to or higher than the surface temperature T (Yes), the process proceeds to step S4, and the heaters 10 and 20 are turned on. That is, when the hydrogen temperature T1 and the air temperature T2 are equal to or higher than the surface temperature T, the hydrogen and air are humidified by the humidifiers 35 and 44, so that dew condensation occurs when hydrogen and air are supplied from the through holes 3a and 3d. And water droplets (droplet water) are generated, and the water droplets diffuse through the communication paths 14g and 15g to the surfaces of the anode electrode 12 and the cathode electrode 13. When the surfaces of the anode electrode 12 and the cathode electrode 13 are covered with water droplets, supply of hydrogen and air to the anode electrode 12 and the cathode electrode 13 is hindered, resulting in a decrease in power generation performance. Therefore, in the present embodiment, the heaters 10 and 20 are provided in the supply side communication holes R1 and R2, and when the hydrogen temperature T1 and the air temperature T2 are determined to be equal to or higher than the surface temperature T, the heaters 10 and 20 are turned on. By turning on and preventing the occurrence of condensation, water droplets can be prevented from being generated. As a result, the power generation performance can be stabilized. In addition, when starting in a low temperature environment (below freezing point), it is possible to prevent the generation of ice that hinders the flow of hydrogen and air on the supply side communication holes R1 and R2, thereby improving the power generation performance at the time of starting and freezing. Problems with the fuel cell stack FC can be reduced. Further, by preventing the generation of water droplets and reducing the hindrance of hydrogen supply to the anode electrode 12, the frequency of unused hydrogen being discharged as off-gas as it is can be reduced, and the reduction in power generation efficiency can be prevented. .

  Further, as shown in FIG. 4A, by laminating a plurality of single cells 1, the inner walls of the supply side communication holes R1 and R2 become uneven as shown by broken lines L1 and L2, but in this embodiment, 4B, since the heaters 10 and 20 inserted into the supply side communication holes R1 and R2 have a sheet shape, the inner walls in the three directions of the supply side communication holes R1 and R2 are It becomes smooth and the factor which disturbs the flow of hydrogen and air flowing through the supply side communication holes R1 and R2 can be reduced. As a result, the pressure loss of the supply side communication holes R1 and R2 is reduced, the variation range of the gas (hydrogen, air) supply between the single cells 1 can be reduced, and the variation of the cell voltage of each single cell 1 can be reduced. become.

  Returning to the flowchart of FIG. 7, when it is determined in step S3 that the hydrogen temperature T1 and the air temperature T2 are not equal to or higher than the surface temperature T (No), the process proceeds to step S5, and the heater 10 is turned off without turning it on. Keep it. That is, when the hydrogen temperature T1 and the air temperature T2 are not equal to or higher than the surface temperature T, the charged hydrogen and air are warmed, so that condensation does not occur. Accordingly, since water droplets (droplet water) are not generated from the humidified hydrogen or air, supply of hydrogen or air to the anode electrode 12 or the cathode electrode 13 is not hindered.

  Then, the process proceeds to step S6, in which the control device 50 determines whether or not the ignition (IG) 70 has been switched off. If the ignition 70 has not yet been switched off (No), the control apparatus 50 returns to step S3. If the ignition 70 is switched to OFF (Yes), the process proceeds to step S7, where the shutoff valve 34 is closed to stop the supply of hydrogen and the air compressor 43 is stopped to stop the supply of air and the fuel cell. System F1 is stopped. In step S7, when the heaters 10 and 20 are powered on, the heaters 10 and 20 are powered off and the fuel cell system F1 is stopped.

  Note that the control of the fuel cell system F1 including the fuel cell stack FC of the present embodiment is not limited to the flowchart shown in FIG. 7, for example, instead of the surface temperature T of the fuel cell stack FC in step S3, As shown in FIG. 4 (b), it is obtained from a rod-shaped temperature sensor arranged in a space between the concave portion of the uneven portion m (see FIG. 4 (a)) of the supply side communication hole R1 and the surface 10a of the heater 10. It is good also as inner wall temperature to be made.

  FIGS. 8A and 8B are plan views showing modifications of the heating means. As shown in FIG. 8, as heating means, for example, sheet-like heaters 10 and 20 such as sheath heaters, rod-like heaters 10A and 20A, and surfaces 10a, 10b, 10c, 20a, 20b and 20c of the heaters 10 and 20 are used. It may be added to the side of the communication paths 14g and 15g where no is formed. However, the rod-like heaters 10A and 20A are formed so as to extend in the stacking direction of the single cells 1 similarly to the heaters 10 and 20, and overlap the bridges 14h and 15h formed in the communication paths 14g and 15g. It is arranged at a position where the 15 g flow path is not blocked. Thus, by adding the heaters 10A and 20A, it becomes possible to more reliably prevent water droplets from being introduced into the communication paths 14g and 15g.

  In the present embodiment, the case where the heaters 10 and 20 are provided in the supply side communication holes R1 and R2 has been described as an example. However, the present invention is not limited to this, and the heaters are provided in the discharge side communication holes R3 and R4. May be added. As a result, the ice that hinders the flow of hydrogen and air over the discharge side communication holes R3 and R4 can be eliminated, so that the power generation performance at the time of starting below the freezing point can be further improved.

  In the present embodiment, the heaters 10 and 20 are provided in the supply side communication holes R1 and R2 of both the anode and the cathode. However, the present invention is not limited to this. For example, only the supply side communication hole R1 on the cathode side is provided. You may make it provide the heater 10 in this.

  In the present embodiment, the through-holes 11a to 11f are formed in the membrane electrode assembly MEA to constitute a part of the supply side communication holes R1 and R2 and the discharge side communication holes R3 and R4. However, the through-holes 11a to 11f are not formed in the membrane electrode assembly MEA. That is, the MEA is configured to be small in size so that the electrolyte membrane 11 has the same area as the anode electrodes 12 and 13, and the through-hole 14a. , 14d, 15a, 15d and seal portions 17a, 17d, 18a, 18d, 19a, 19d constitute supply side communication holes R1, R2, discharge side communication holes R3, R4, and a cooling medium communication hole. Good.

The fuel cell stack of this embodiment is shown, (a) is a disassembled perspective view, (b) is a side view. It is a disassembled perspective view which shows the laminated structure of a single cell. (A) is a top view which shows the anode side separator, (b) is a top view which shows the cathode side separator. FIG. 1B is a cross-sectional view taken along the line AA of FIG. 1B, in which FIG. 1A shows a state before the heating means is attached, and FIG. (A)-(c) is sectional drawing which shows the attachment method of a heating means, respectively. It is a whole lineblock diagram showing an example of a fuel cell system carrying a fuel cell stack of this embodiment. It is a flowchart which shows operation | movement of a fuel cell system. The modification of a heating means is shown, (a) is a top view which shows the separator by the side of an anode, (b) is a top view which shows the separator by the side of a cathode.

Explanation of symbols

1 Single cell 2 Laminate 10,20 Heater (heating means)
11 Solid polymer electrolyte membrane (electrolyte membrane)
12 Anode electrode (electrode)
13 Cathode electrode (electrode)
14, 15 Separator FC Fuel cell stack R1, R2 Supply side communication hole R3, R4 Discharge side communication hole

Claims (8)

A laminated body in which a plurality of unit cells configured by sandwiching a membrane electrode assembly formed by arranging a pair of electrodes on both surfaces of an electrolyte membrane with a pair of separators are stacked in the thickness direction, A supply-side communication hole for supplying a reaction gas to the electrode of each single cell through the separator in the thickness direction and a discharge-side communication hole for discharging off-gas from each single cell were provided. An internal manifold type fuel cell stack,
Supply-side heating means is provided in front Symbol supply passage,
The separator includes a reaction gas flow path for flowing the reaction gas in a region corresponding to the electrode, and a supply side communication path for communicating the reaction gas flow path and the supply side communication hole,
The fuel cell stack, wherein the supply side heating means has a shape that covers an inner wall of the supply side communication hole except for an inner wall on the supply side communication path side .   The supply side communication path has a plurality of bridges arranged at intervals in the width direction,
  2. The fuel cell stack according to claim 1, wherein the supply-side heating unit is disposed at a position corresponding to the bridge on the inner wall on the supply-side communication path side.   The separator has a rectangular shape,
  The fuel cell stack according to claim 1, wherein the supply side communication hole is disposed at a corner of the separator.   The fuel cell stack according to any one of claims 1 to 3, wherein a communication hole through which a cooling medium flows is disposed adjacent to the supply side communication hole.   The inner wall of the supply-side communication hole is formed to be uneven by stacking the single cells,
  5. The fuel cell stack according to claim 1, wherein an outer surface of the supply-side heating unit is configured along irregularities of the inner wall.   The discharge side communication hole is provided with a discharge side heating means,
  The separator includes a discharge side communication path that communicates the reaction gas flow path and the discharge side communication hole,
  The discharge side heating means has a shape covering an inner wall excluding an inner wall on the discharge side communication path side among inner walls constituting the discharge side communication hole. The fuel cell stack according to item.   A first temperature sensor for detecting a temperature of the reaction gas charged into the laminate;
  A second temperature sensor for detecting the surface temperature of the laminate,
  The fuel cell stack according to any one of claims 1 to 6, further comprising a control device that controls the supply-side heating unit based on a temperature of the reaction gas and the surface temperature. The fuel cell stack according to any one of claims 1 to 7, wherein the supply side heating means has a sheet shape.

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