JP2006079849A - Separator of fuel cell and fuel cell device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve utilization efficiency of energy in a fuel cell. <P>SOLUTION: The fuel cell main body 1 is provided with a collecting plate 2, a collecting plate 3, and a plurality of membrane electrode junctions 4 as well as a plurality of double-sided separators 5 alternately laminated between the collecting plate 2 and the collecting plate 3. An anode gas flow channel 71 is formed at one face of each double-sided separator, and a cathode gas flow channel at the other face. A combustion gas supply flow channel 74 communicated with the anode gas flow channel 71, a cathode gas supply flow channel 75 communicated with the cathode gas flow channel 76, and a heat exchange flow channel 73 communicated with the combustion gas supply flow channel 74 and the cathode gas supply flow channel 75, are formed on an inside face of each double-sided separator 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell separator in which an anode gas channel and a cathode gas channel are formed, and further relates to a fuel cell device using the separator.

  In recent years, research and development have been actively conducted on fuel cells that can achieve high energy use efficiency. A fuel cell is one that directly extracts electrical energy from chemical energy by electrochemically reacting hydrogen gas in the anode gas and oxygen gas in the air, and is positioned as a promising battery with great potential. Yes.

  Conventional fuel cells are stacked by alternately laminating separators and membrane electrode assemblies, and a membrane electrode assembly sandwiched between two separators is used as one power generation cell (see, for example, Patent Document 1). ). The membrane electrode assembly is a laminate in which gas diffusion layers are laminated on both sides of a solid polymer electrolyte membrane. The separator is a channel in which a channel is formed on both sides. The channel formed on one side of the separator has an anode. The gas flows, and the cathode gas flows through the flow path formed on the other surface.

In order to efficiently generate power with the fuel cell, there is an appropriate temperature, and it is necessary to heat or cool the fuel cell in order to keep the fuel cell at an appropriate temperature. For this purpose, an electric heating material is provided in the fuel cell and heated by the electric heating material (see Patent Document 1).
JP 2002-313391 A

However, in order to heat a fuel cell with an electric heating material, since electric power is required, the energy utilization efficiency was bad.
Therefore, the present invention has been made to solve the above-described problems, and an object thereof is to improve the efficiency of energy use in a fuel cell.

  In order to solve the above problems, the separator of the fuel cell of the present invention has an anode gas flow path through which the anode gas flows on one side and a cathode gas flow path through which the cathode gas flows on the other side, An internal flow path that communicates with the anode gas flow path and communicates with the cathode gas flow path is provided between the one surface and the other surface, and a combustion catalyst is provided on the wall surface of the internal flow path. .

  The fuel cell device of the present invention comprises a membrane electrode assembly having a solid polymer electrolyte membrane and a pair of gas diffusion layers facing each other with the solid polymer electrolyte membrane sandwiched therebetween, and the membrane electrode assembly laminated alternately A separator, and the separator has an anode gas flow path through which anode gas flows on one side and a cathode gas flow path through which cathode gas flows on the other side, the anode Having an internal flow path communicating with the gas flow path and communicating with the cathode gas flow path between the one surface and the other surface, and having a combustion catalyst on the wall surface of the internal flow path Features.

  As described above, since the internal flow channel communicates with the anode gas flow channel and the cathode gas flow channel, the anode gas flowing through the anode gas flow channel flows into the internal flow channel, and the cathode gas flowing through the cathode gas flow channel is also the internal flow channel. Flow into. Therefore, the cathode gas and the anode gas flow in the internal flow path, but since the combustion catalyst is provided on the wall surface of the internal flow path, the remaining combustible fuel or fuel remaining without being consumed by the fuel cell in the anode gas. The reformed combustible reacts with oxygen in the cathode gas to generate combustion heat. Accordingly, the fuel cell device and the separator are heated. Thus, since the fuel cell device is heated not by the electric heating material but by combustion of components in the anode gas released to the outside after power generation, the energy utilization efficiency is improved.

  Moreover, since the internal flow path is formed inside the separator, the combustion heat in the internal flow path is hardly transmitted to the outside. In particular, in a fuel cell device in which membrane electrode assemblies and separators are alternately stacked, an internal flow path is formed inside the separator. Therefore, the membrane is more than in the case where an electric heating material or the like is provided on the outer surface of the fuel cell device. Heat is easily transmitted to the gas diffusion layer of the electrode assembly, and the combustion heat can be efficiently used for the electrochemical reaction of the fuel cell device.

  In the present invention, it is preferable that the internal flow path communicates with a terminal portion of the anode gas flow path.

  As described above, since the internal flow path communicates with the terminal portion of the anode gas flow path, the anode gas that has flowed through the anode gas flow path flows into the internal flow path. That is, in the electrochemical reaction in the membrane electrode assembly, unreacted combustible fuel or anode gas containing combustible material modified from the fuel flows into the internal flow path. The combustible material can be used effectively for combustion reaction. Therefore, energy use efficiency is improved.

  In the present invention, it is preferable that the separator has a cathode gas introduction hole for introducing a cathode gas, and the internal channel and the cathode gas channel communicate with each other through the cathode gas introduction hole.

  As described above, since the internal flow path and the cathode gas flow path communicate with each other through the cathode gas introduction hole, fresh cathode gas is supplied from the cathode gas introduction port to both the cathode gas flow path and the internal flow path.

  In the present invention, the separator has an anode gas discharge passage for discharging an anode gas, and has an anode gas discharge passage communicating from a terminal portion of the anode gas passage to the anode gas discharge hole, and the anode It is preferable to have an anode gas valve for adjusting the opening amount of the gas discharge channel in the middle of the anode gas discharge channel.

  As described above, since the anode gas valve is provided in the middle of the anode gas discharge channel, the anode gas flowing through the anode gas channel becomes the anode gas discharge channel as the opening amount of the anode gas valve increases. It becomes easy to flow, and it becomes easy to discharge | emit from an anode gas discharge hole, and conversely becomes difficult to flow into an internal flow path. Therefore, combustion hardly occurs in the internal flow path, and the separator and the fuel cell device are air-cooled by the cathode gas flowing through the internal flow path.

  On the other hand, as the opening amount of the anode gas valve decreases, the anode gas that has flowed through the anode gas flow path becomes difficult to flow into the anode gas discharge flow path, and conversely, the anode gas easily flows into the internal flow path. Therefore, combustion easily occurs in the internal flow path, and the separator and the fuel cell device are heated by the combustion heat in the internal flow path.

  As described above, the temperature control of the separator and the fuel cell device can be performed by adjusting the opening amount of the anode gas valve.

  In the present invention, the internal flow path is a combustion gas flow path that communicates from the terminal portion of the anode gas flow path to the merge part, a cathode gas supply flow path that communicates from the cathode gas flow path to the merge part, It is preferable to have a heat exchange flow path communicating from the junction to the anode gas discharge hole.

  As described above, the anode gas that has flowed through the anode gas flow path flows into the combustion gas flow path, the cathode gas flows from the cathode gas flow path into the cathode gas supply flow path, and the anode gas and the cathode gas are mixed at the junction. To do. Then, the gas mixture of the anode gas and the cathode gas flows through the heat exchange channel, and combustion occurs in the heat exchange channel. In this way, the unreacted combustible fuel in the anode gas or the combustible material modified with the fuel burns, so that the unreacted combustible fuel or the combustible material modified with the fuel is effectively used for the combustion reaction Energy utilization efficiency can be improved.

  In the present invention, it is preferable that the separator has a cathode gas valve for adjusting an opening amount of the cathode gas supply channel in the middle of the cathode gas supply channel.

  As described above, since the cathode gas valve is provided in the middle of the cathode gas supply channel, the amount of cathode gas supplied to the heat exchange channel can be adjusted.

  In the present invention, the fuel cell device measures the input current of the DC-DC converter that inputs the power generated by the membrane electrode assembly, and the DC-DC converter, and the anode gas valve according to the input current. It is preferable to include a control unit that controls the opening amount.

  As described above, the temperature of the separator and the fuel cell device can be controlled by adjusting the opening amount of the anode gas valve by the control unit. Further, the input current of the DC-DC converter depends on the electric energy generated in the membrane electrode assembly, and further depends on the amount of combustible fuel reacted in the membrane electrode assembly or the combustible material reforming the fuel. Therefore, the unreacted combustible fuel or the amount of combustible material reformed from the fuel can be grasped from the input current of the DC-DC converter. That is, controlling the opening amount of the anode gas valve in accordance with the input current of the DC-DC converter controls the opening amount of the anode gas valve in accordance with the amount of unreacted combustible fuel or combustible material obtained by reforming the fuel. Is substantially the same. Thus, since the opening amount of the anode gas valve is controlled in accordance with the amount of unreacted combustible fuel or the amount of combustible material obtained by reforming the fuel, the temperature control of the separator and the fuel cell device can be performed more accurately. .

  In this invention, it is preferable that the said control part controls the opening amount of the said cathode gas valve | bulb according to the input current of the said DC-DC converter.

  As described above, the amount of cathode gas supplied to the heat exchange flow path can be adjusted by adjusting the opening amount of the cathode gas valve in the control unit. Further, since the input current of the DC-DC converter depends on the amount of combustible fuel reacted in the membrane electrode assembly or the amount of combustible material reformed, the unreacted combustible from the input current of the DC-DC converter. The amount of fuel or combustible material reformed can be grasped. That is, controlling the opening amount of the cathode gas valve in accordance with the input current of the DC-DC converter controls the opening amount of the cathode gas valve in accordance with the amount of unreacted combustible fuel or combustible material modified from the fuel. Since it is substantially the same as that, it is possible to supply an appropriate amount of cathode gas for burning unreacted combustible fuel or combustible reformed fuel. Therefore, the temperature control of the separator and the fuel cell device can be performed more accurately.

  According to the present invention, since the fuel cell device is heated by the combustion of the anode gas, not the electric heating material, the energy utilization efficiency is improved.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

FIG. 1 is a block diagram of the power generation device 200.
The power generation device 200 includes a desktop personal computer, a notebook personal computer, a mobile phone, a PDA (Personal Digital Assistant), an electronic notebook, a wristwatch, a digital still camera, a digital video camera, a game device, a game machine, a household electric device, It is provided in other electronic devices and is used as a power source for operating the electronic device main body.

  The power generation apparatus 200 includes a fuel container 201 that stores fuel such as methanol and water separately or in a mixed state, a vaporizer 203 that vaporizes the fuel and water supplied from the fuel container 201, and fuel from the fuel container 201. A fuel pump 202 that sucks water and supplies the sucked fuel and water to the vaporizer 203, and a mixture of the fuel and water supplied from the vaporizer 203 with hydrogen gas, carbon dioxide gas, etc. The reformer 204 generated as shown in (2) and the carbon monoxide in the gas mixture supplied from the reformer 204 are oxidized as shown in the chemical reaction formula (3), so that the carbon monoxide from the gas mixture. A carbon monoxide remover 205 that removes carbon dioxide, and a fuel cell main body 1 that generates electric energy by an electrochemical reaction between hydrogen gas and oxygen gas in the outside air of the gas mixture supplied from the carbon monoxide remover 205 Comprises an air pump 206 for supplying suction air to the carbon monoxide remover 205, and the fuel cell body 1 sucks the outside air of the air.

CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ (1)
2CH ₃ OH + H ₂ O → 5H ₂ + CO + CO ₂ (2)
2CO + O ₂ → 2CO ₂ (3)

  The vaporizer 203, the fuel pump 202, the reformer 204, the carbon monoxide remover 205, and the air pump 206 are mounted on the electronic device body. On the other hand, the fuel container 201 is provided so as to be detachable from the electronic apparatus main body. When the fuel container 201 is attached to the electronic apparatus main body, the fuel in the fuel container 201 is vaporized by the fuel pump 202 by the vaporizer 203. Sent to. The fuel cell main body 1 may be detachably attached to the electronic device main body, or may be fixed to the electronic device main body.

  As the fuel stored in the fuel container 201, a compound containing hydrogen atoms such as alcohols such as ethanol or gasoline can be used instead of methanol.

  A fuel cell device according to an embodiment to which the present invention is applied includes the fuel cell main body 1 and a controller 80 as shown in FIG.

  FIG. 2 is an end view of a cut surface parallel to the thickness direction of the stack type fuel cell main body 1. As shown in FIG. 2, the fuel cell main body 1 is formed by stacking a plurality of fuel cell units so that they are electrically connected in series. The fuel cell main body 1 includes a negative current collector plate 2, a positive current collector plate 3 substantially parallel to the current collector plate 2, and a current collector plate 2 and a current collector plate 3 alternately. A plurality of laminated membrane electrode assemblies (MEA) 4 and a plurality of double-sided separators 5 are provided, and are tightened in the thickness direction by bolt and nut coupling (not shown). Each fuel cell unit has a structure in which the membrane electrode assembly 4 is sandwiched between two double-sided separators 5, 5, a structure sandwiched between the current collector plate 2 and the double-sided separator 5, or the current collector plate 3 and the double-sided separator 5. It is a structure sandwiched between. One side of the double-sided separator 5 is disposed on the hydrogen electrode side of the fuel cell unit, and the other surface is disposed on the oxygen electrode side of another adjacent fuel cell unit. When the bolt-nut connection is removed, the fuel cell main body 1 can be separated into current collector plates 2 and 3, a plurality of membrane electrode assemblies 4, and a plurality of double-sided separators 5. In FIG. 2, the number of fuel cell units is four, but is not limited thereto.

  The membrane electrode assembly 4 will be described with reference to FIGS. FIG. 3 is a plan view of the membrane electrode assembly 4, and FIG. 4 is a cross-sectional view taken along the line IV-IV shown in FIG. As shown in FIGS. 3 and 4, the membrane / electrode assembly 4 includes a solid polymer electrolyte membrane 6, gas diffusion layers 7 and 8, catalysts 9 and 10, and gaskets 11 and 12. ing.

The solid polymer electrolyte membrane 6 is a membrane formed in a rectangular shape or a square shape, and selectively transmits hydrogen ions (H ⁺ ). Catalysts 9 and 10 are formed in a rectangular shape or a square shape on both surfaces of the solid polymer electrolyte membrane 6 and in the respective central portions. A gas diffusion layer 7 having gas permeability and electrical conductivity is formed on the catalyst 9, and a gas diffusion layer 8 having gas permeability and electrical conductivity is formed on the catalyst 10. The gas diffusion layer 7 functions as an anode (hydrogen electrode), and the gas diffusion layer 8 functions as a cathode (oxygen electrode). The gasket 11 is provided in a rectangular frame shape or a square frame shape so as to surround the gas diffusion layer 7, and the gasket 12 is provided in a rectangular frame shape or a square frame shape so as to surround the gas diffusion layer 8. The outer edge side of the solid polymer electrolyte membrane 6 is sandwiched between the gaskets 11 and 12. Each of the gaskets 11 and 12 is provided with a hole 29 into which a bolt is inserted in the vicinity of each apex angle.

  As shown in FIG. 3, around the gas diffusion layer 7, the anode gas introduction hole 15, the anode gas discharge hole 16, the cathode gas introduction hole 17 and the cathode gas discharge hole 18 penetrate from the surface of the gasket 11 to the surface of the gasket 12. It is formed to do. The anode gas means a gas containing hydrogen gas, specifically, a gas containing hydrogen gas generated by the reformer 204 or other by-product gas (for example, carbon dioxide gas). . The cathode gas means a gas containing oxygen gas, specifically air. The anode gas is supplied from the carbon monoxide remover 205 described above, and the cathode gas is supplied by the air pump 206.

  The double-sided separator 5 will be described with reference to FIGS. 5 is a plan view of a surface of the double-sided separator 5 that is in contact with the gas diffusion layer 7, and FIG. 6 is a surface that is opposite to the surface of FIG. 5 and that is in contact with the gas diffusion layer 8. FIG. 7 is a cross-sectional view taken along the line VII-VII shown in FIG. 5 and FIG.

  The double-sided separator 5 includes three metal plates 19, 20, 21, an anode gas valve 22, and a cathode gas valve 23. The metal plates 19, 20, and 21 are formed by forming stainless steel (SUS) into a rectangular plate or a square plate. These metal plates 19, 20, and 21 are laminated in this order and joined by diffusion bonding, and gold plating is applied to the entire surfaces of the joined metal plates 19, 20, and 21 to reduce contact resistance. The joining of the metal plates 19, 20, and 21 is not limited to diffusion joining, and other joining methods may be used. The metal plates 19, 20, 21 have holes 30 in which bolts are inserted in the vicinity of the respective apex angles. Here, in the drawing, the gold plating is very thin as compared with the metal plates 19, 20, and 21, and therefore, the gold plating is not shown in order to simplify the drawing.

  An anode gas introduction hole 25, an anode gas discharge hole 26, a cathode gas introduction hole 27, and a cathode gas discharge hole 28 that penetrate from one surface to the other surface are formed in the joined body of these metal plates 19, 20, and 21. Has been. Here, the anode gas introduction hole 25 is formed at a position opposite to the anode gas introduction hole 15 of the membrane electrode assembly 4, and the anode gas discharge hole 26 is located at a position opposite to the anode gas discharge hole 16 of the membrane electrode assembly 4. The cathode gas introduction hole 27 is formed at a position opposite to the cathode gas introduction hole 17 of the membrane electrode assembly 4, and the cathode gas discharge hole 28 is located at a position opposite to the cathode gas discharge hole 18 of the membrane electrode assembly 4. Is formed. The holes 30 of the metal plates 19, 20, 21 are formed at positions opposite to the holes 29 of the gaskets 11, 12.

  FIG. 8 is a plan view of the metal plate 21 when viewed in the direction of arrow A in FIG. As shown in FIG. 8, a meandering groove 31 is formed on one surface of the metal plate 21 (joint surface with the membrane electrode assembly 4) at the center thereof. In one end portion of the meandering groove 31, the perforation 32 penetrates to the opposite surface (joint surface with the metal plate 20), and in the other end portion of the meandering groove 31, the perforation 33 penetrates to the opposite surface. On the opposite surface, a long groove 34 led from the anode gas introduction hole 25 to the perforation 32, a long groove 35 led from the perforation 33, and a long groove led from the anode gas discharge hole 26 to the vicinity of the tip of the long groove 35 are provided. 36 is recessed.

  This opposite surface is a joint surface with the metal plate 20, and the long grooves 34, 35, 36 are covered with the metal plate 20 when the metal plate 21 and the metal plate 20 are joined. By joining the surface of the membrane electrode assembly 4 on the hydrogen electrode side to the metal plate 21, the meandering groove 31 is covered with the gas diffusion layer 7. By covering the meandering groove 31 and the long groove 34, a flow path 71 is formed which continues from the anode gas introduction hole 25 to the perforation 33 via the long groove 34 and the meandering groove 31. The flow path 71 facing the gas diffusion layer 7 of the joined body 4 is referred to as an anode gas flow path 71. The starting end portion of the anode gas passage 71 communicates with the anode gas introduction hole 25, and the end portion of the anode gas passage 71 is a perforation 33. The meandering groove 31, the perforations 32 and 33, and the long grooves 34, 35, and 36 are formed by etching before joining the metal plate 21 and the metal plate 20.

  FIG. 9 is a plan view of the metal plate 20 when viewed in the direction of arrow A shown in FIG. As shown in FIG. 9, a meandering groove 37 having a fold shape is formed at the center of the joint surface of the metal plate 20 with the metal plate 21. A combustion catalyst for burning (oxidizing) hydrogen is carried on the wall surface of the meandering groove 37.

  One end portion of the meandering groove 37 is led to the anode gas discharge hole 26, and the other end portion of the meandering groove 37 joins the long groove 39 and the long groove 40 at the joining portion 38. The long groove 39 is recessed from the joining portion 38 to a position corresponding to the perforation 33 of the metal plate 21, and the long groove 40 is recessed from the joining portion 38 to the perforation 41 penetrating through the opposite surface (joining surface with the metal plate 19). Yes. Further, in the vicinity of the perforation 41, a perforation 42 penetrating from the joint surface with the metal plate 21 to the joint surface with the metal plate 19 is provided. In addition, a long groove 43 led from the perforation 42 to the cathode gas introduction hole 27 is formed in the joint surface with the metal plate 21. A circular counterbore 44 is formed on the opposite surface (joint surface with the metal plate 19), and a perforation 41 and a perforation 42 are formed on the bottom of the counterbore 44. In addition, a circular counterbore 45 is formed in the vicinity of the end of the anode gas discharge hole 26 and the long groove 39 on the side opposite to the joining portion 38 on the joint surface with the metal plate 19. A perforation 46 and a perforation 47 penetrating to the joint surface with the metal plate 21 are formed. The perforations 46 are at positions corresponding to the tips of the long grooves 35 of the metal plate 21, and the perforations 47 are at positions corresponding to the tips of the long grooves 36 of the metal plate 21.

  By joining the metal plate 20 and the metal plate 21, the meandering groove 37 and the long grooves 39, 40, 43 are covered with the metal plate 21, and a flow path 73 from the junction 38 to the anode gas discharge hole 26 is formed. At the same time, a flow path 75 from the cathode gas introduction hole 27 to the junction 38 through the long groove 43, the perforations 42 and 41, the counterbore 44 and the long groove 40 is formed. Hereinafter, the flow path 73 is referred to as a heat exchange flow path 73, and the flow path 75 is referred to as a cathode gas supply flow path 75. The start end of the cathode gas supply channel 75 communicates with the cathode gas introduction hole 27, the end portion of the cathode gas supply channel 75 serves as the junction 38, and the start end of the heat exchange channel 73 serves as the cathode gas at the junction 38. The end portion of the heat exchange channel 73 communicates with the anode gas discharge hole 26 and communicates with the supply channel 75.

  Further, as shown in FIGS. 8 and 9, the metal plate 20 and the metal plate 21 are joined so that the tip of the long groove 39 and the perforation 33 overlap with each other, so that the end portion of the anode gas flow channel 71 passes through the perforation 33. A flow path 74 from the perforation 33 to the joining portion 38 is formed in communication with the distal end of the long groove 39. Hereinafter, the flow path 74 is referred to as a combustion gas supply flow path 74. The starting end of the combustion gas supply channel 74 communicates with the end of the anode gas channel 71 through the perforations 33, and the end of the combustion gas supply channel 74 is connected to the cathode gas supply channel 75 and the heat exchange flow at the junction 38. It communicates with the road 73.

  Further, since the metal plate 20 and the metal plate 21 are joined so that the tip of the long groove 35 and the perforation 46 overlap and the tip of the long groove 36 and the perforation 47 overlap, the long groove 35 passes through the perforations 46 and 47 and the counterbore 45. Thus, a flow path 72 from the perforation 33 to the anode gas discharge hole 26 is formed. Hereinafter, this flow path 72 is referred to as an anode gas discharge flow path 72. The starting end portion of the anode gas discharge channel 72 communicates with the end portion of the anode gas channel 71 through the perforations 33, and the end portion of the anode gas discharge channel 72 communicates with the anode gas discharge hole 26.

  FIG. 10 is a plan view of the metal plate 19 when viewed in the direction of arrow A shown in FIG. As shown in FIG. 10, a meandering groove 48 is formed on one surface of the metal plate 19 (joint surface with the membrane electrode assembly 4) at the center thereof. In one end portion of the meandering groove 48, the perforation 49 penetrates to the opposite surface (joint surface with the metal plate 20), and in the other end portion of the meandering groove 48, the perforation 50 penetrates to the opposite surface. On the opposite surface, a long groove 51 led from the cathode gas introduction hole 27 to the perforation 49 and a long groove 52 led from the perforation 50 to the cathode gas discharge hole 28 are recessed. Further, circular mounting holes 54 and 53 are formed so as to penetrate the metal plate 19 at positions concentric with the spot facings 44 and 45 of the metal plate 20. The diameter of the mounting hole 54 is larger than the diameter of the spot facing 44, and the diameter of the mounting hole 53 is larger than the diameter of the spot facing 45.

  The meandering groove 48, the perforations 49 and 50, the long grooves 51 and 52, and the attachment holes 53 and 54 are formed by etching before joining the metal plate 19 and the metal plate 20, and the metal plate 19 and the metal plate 20 are joined. Thus, the long grooves 51 and 52 are covered with the metal plate 20. On the other hand, the meandering groove 48 is covered with the gas diffusion layer 8 by joining the surface on the oxygen electrode side of the membrane electrode assembly 4 to the metal plate 19. By covering the meandering groove 48 and the long grooves 51, 52, a flow path 76 is formed that extends from the cathode gas introduction hole 27 to the cathode gas discharge hole 28 via the long groove 51, the meandering groove 48, and the long groove 52. Hereinafter, the flow path 76 facing the gas diffusion layer 8 of the membrane electrode assembly 4 is referred to as a cathode gas flow path 76 in the following. The cathode gas channel 76 has a start end communicating with the cathode gas introduction hole 27, a terminal end of the cathode gas channel 76 communicating with the cathode gas discharge hole 28, and the cathode gas channel 76 and the cathode gas supply channel 75 are connected to each other. The cathode gas introduction hole 27 communicates.

  One surface of both surfaces of the laminate of the metal plates 19 to 21 is a surface where the anode gas flow channel 71 of the fuel cell unit is formed, and the other surface is another fuel cell adjacent to the fuel cell unit. It is the surface where the cathode gas flow path 76 of the unit is formed. An internal flow path including a combustion gas supply flow path 74, a cathode gas supply flow path 75, and a heat exchange flow path 73 is formed inside the two surfaces.

  As shown in FIGS. 5 to 7, an anode gas valve 22 that adjusts the opening amount of the anode gas discharge channel 72 is attached to the middle part of the anode gas discharge channel 72. Specifically, the anode gas valve 22 is fitted into the mounting hole 53, and the counterbore 45 is closed by the anode gas valve 22. The anode gas valve 22 is a piezoelectric element type or MEMS (Micro Electro Mechanical Systems) type actuator. Further, a closing rubber 22 a is provided in a central portion of the anode gas valve 22 and facing the perforation 46. The anode gas valve 22 is configured to open and close the perforations 46 with the rubber 22a by vibrating. The anode gas valve 22 adjusts the flow rate of the fluid flowing through the anode gas discharge passage 72 by adjusting the opening amount of the perforation 46.

  A cathode gas valve 23 that adjusts the opening amount of the cathode gas supply channel 75 is attached to the middle part of the cathode gas supply channel 75. Specifically, a piezoelectric element type or MEMS type cathode gas valve 23 is fitted into the mounting hole 54, and the counterbore 44 is closed by the cathode gas valve 23. The cathode gas valve 23 is configured to open and close the perforation 42 with the closing rubber 23a by vibrating. The cathode gas valve 23 adjusts the flow rate of the fluid flowing through the cathode gas supply channel 75 by opening and closing the perforations 42 and adjusting the opening amount of the perforations 42.

  The current collector plate 2 will be described with reference to FIG. The current collector plate 2 is formed by laminating a plurality of metal plates having holes in a predetermined shape. As shown in FIG. 2, the current collector plate 2 is formed with an anode gas discharge hole 86 and a cathode gas introduction hole 87 penetrating from one surface to the other surface. The anode gas discharge hole 86 is formed at a position opposite to the anode gas discharge hole 16 of the membrane electrode assembly 4 and the anode gas discharge hole 26 of the double-sided separator 5, and the cathode gas introduction hole 87 is the cathode of the membrane electrode assembly 4. It is formed at a position facing the gas introduction hole 17 and the cathode gas introduction hole 27 of the double-sided separator 5. Therefore, when the current collector plate 2, the membrane electrode assembly 4 and the double-sided separator 5 are stacked, the anode gas discharge hole 86 of the current collector plate 2, the anode gas discharge hole 16 of the membrane electrode assembly 4 and the anode gas of the double-sided separator 5. The discharge holes 26 communicate with each other, and the cathode gas introduction holes 87 of the current collector plate 2, the cathode gas introduction holes 17 of the membrane electrode assembly 4, and the cathode gas introduction holes 27 of the double-sided separator 5 communicate with each other.

Like the metal plate 20, the current collector plate 2 has a long groove 35, a long groove 36, a meandering serpentine groove 37 (73), a merging portion 38, a long groove 39, a long groove 40, a perforation 41, a perforation 42, a long groove 43, Counterbore 44, perforation 46 and perforation 47 are provided. Similar to the anode gas flow path 71 having a meandering groove 31 provided in the metal plate 21 at the central portion of the current collector plate 2 on the joint surface with the membrane electrode assembly 4. An anode gas flow path 89 that is a twisted groove is formed. One end of the anode gas flow path 89 communicates with the anode gas introduction hole 15 of the membrane electrode assembly 4, and the other end of the anode gas flow path 89 communicates with the long groove 35. The current collector plate 2 further includes an anode gas valve storage chamber 61 in which an anode gas valve 22 and a rubber 22a are provided, like the double-sided separator 5. In the current collector plate 2, the anode gas valve storage chamber 61 communicates with the perforations 46 and 47 in the current collector plate 2, the perforations 47 communicate with the long grooves 36, and the long grooves 36 communicate with the anode gas discharge holes 86. Yes. When the surface on which the anode gas flow path 89 is formed is bonded to the membrane electrode assembly 4, the anode gas flow path 89 is covered with the gas diffusion layer 7.
The twisted meandering groove 37 and the anode gas flow path 89 in the current collector plate 2 overlap each other in a plane. Like the double-sided separator 5, the counterbore 44 of the current collector plate 2 is provided with the anode gas valve 22, and the long groove 43 communicates with the cathode gas introduction hole 87.

  The current collector plate 3 is formed with an anode gas introduction hole 85 and a cathode gas discharge hole 88 penetrating from one surface to the other surface. The anode gas introduction hole 85 is formed at a position opposite to the anode gas introduction hole 15 of the membrane electrode assembly 4 and the anode gas introduction hole 25 of the double-sided separator 5, and the cathode gas discharge hole 88 is a cathode of the membrane electrode assembly 4. The gas discharge hole 18 and the cathode gas discharge hole 28 of the double-sided separator 5 are formed at positions opposite to each other. Therefore, when the current collector plate 3, the membrane electrode assembly 4 and the double-sided separator 5 are laminated, the anode gas introduction hole 85 of the current collector plate 3, the anode gas introduction hole 15 of the membrane electrode assembly 4 and the anode gas of the double-sided separator 5 are used. The introduction holes 25 communicate with each other, and the cathode gas discharge holes 88 of the current collector plate 2, the cathode gas discharge holes 18 of the membrane electrode assembly 4, and the cathode gas discharge holes 28 of the double-sided separator 5 communicate with each other.

  A cathode gas flow path 90 that is a crease-like groove is formed at the center of the current collector plate 3 on the joint surface with the membrane electrode assembly 4, and one end of the cathode gas flow path 90 is The cathode electrode introduction hole 17 of the membrane electrode assembly 4 communicates with the other end of the cathode gas flow path 90 and communicates with the cathode gas discharge hole 88.

  As shown in FIG. 2, a temperature sensor 60 that measures the temperature of the fuel cell body 1 and outputs the measured temperature as an electrical signal is provided on the outer wall of the fuel cell body 1 as temperature measurement means.

  Further, tubular bases 65, 66, 67, and 68 are fitted in the anode gas introduction hole 85, the anode gas discharge hole 86, the cathode gas introduction hole 87, and the cathode gas discharge hole 88, respectively. The base 65 is connected to a carbon monoxide remover 205 so that the anode gas generated by the reformer 204 is supplied from the carbon monoxide remover 205 to the anode gas introduction holes 15, 25, 85. The base 67 communicates with the outside air, and the cathode gas is supplied to the cathode gas introduction holes 17, 27 and 87 through the base 67 by the pump 206.

The generation of electric power by the fuel cell main body 1 will be described.
The anode gas supplied to the anode gas introduction holes 15, 25, 85 through the base 65 flows through the anode gas flow paths 71, 89 and is discharged from the anode gas discharge holes 16, 26, 86. When the anode gas flows through the anode gas flow paths 71 and 89, the hydrogen gas is separated into hydrogen ions and electrons by the action of the catalyst 9 as shown in the electrochemical reaction formula (4), and the electrons are The hydrogen ions are taken out by the gas diffusion layer 7 and permeate the solid polymer electrolyte membrane 6.
H ₂ → 2H ⁺ + 2e ⁻ (4)

Through the base 67, a cathode gas containing oxygen gas (here, air) is supplied to the cathode gas introduction holes 17, 27, 87, and the cathode gas supplied to the cathode gas introduction holes 17, 27, 87 is the cathode gas flow path. 76 and 90 are discharged from the cathode gas discharge holes 18, 28 and 88. When the cathode gas is flowing through the cathode gas flow paths 76 and 90, oxygen is subjected to the action of the catalyst 10 as shown in the electrochemical reaction formula (5), and the hydrogen ions that have permeated the solid polymer electrolyte membrane 6 and It reacts with the electrons conducted to the gas diffusion layer 8 to generate water.
2H ⁺ + 1 / 2O ₂ + 2e ⁻ → H ₂ O (5)

  As described above, electric power is generated in each membrane electrode assembly 4. The membrane electrode assembly 4, the double-sided separator 5 and the current collector plates 2 and 3 are laminated so that the gas diffusion layers 7 and 8 of the membrane electrode assembly 4 are in contact with the conductive double-sided separator 5 and the current collector plates 2 and 3. Therefore, when the membrane electrode assembly 4 is a unit cell, the unit cells are connected in series. Therefore, the current collector plate 2 becomes a negative pole and the current collector plate 3 becomes a positive pole. In addition, the current collector plate 2 and the current collector plate 3 are connected to a later-described DC-DC converter 102 through lead wires or the like, and the power generated by the plurality of membrane electrode assemblies 4 is collected by the current collector plate 2 and the current collector plate. 3 to the DC-DC converter 102.

The opening and closing of the anode gas valve 22 and the cathode gas valve 23 and the gas flow will be described.
When the anode gas valve 22 is closed, the anode gas that has flowed through the anode gas passage 71 flows to the anode gas discharge holes 16, 26, 86 via the combustion gas supply passage 74 and the heat exchange passage 73. On the other hand, when the anode gas valve 22 is open, the anode gas does not flow from the anode gas flow channel 71 to the combustion gas supply flow channel 74 and the heat exchange flow channel 73 but directly flows to the anode gas discharge holes 16, 26, 86. .

  In addition, when the cathode gas valve 23 is open, the cathode gas supplied from the cathode gas introduction hole 27 passes through the cathode gas supply channel 75 and the heat exchange channel 73, and the cathode gas discharge holes 18, 28, 88. To flow. On the other hand, when the cathode gas valve 23 is closed, the cathode gas supplied from the cathode gas introduction hole 27 does not flow into the heat exchange flow path 73. The cathode gas flow path 76 is not limited to the opening and closing of the cathode gas valve 23, and the cathode gas flows from the cathode gas introduction hole 27 and discharges the cathode gas to the cathode gas discharge holes 18, 28 and 88.

  Further, when the anode gas valve 22 is closed and the cathode gas valve 23 is opened, the cathode gas and the anode gas are mixed at the junction 38, and the mixture flows through the heat exchange flow path 73. At this time, the anode gas passing through the combustion gas supply channel 74 contains hydrogen that does not permeate the solid polymer electrolyte membrane 6 and remains, and the mixture of the anode gas and the cathode gas exchanges heat. When flowing through the flow path 73, the remaining hydrogen gas and oxygen gas are subjected to the action of a combustion catalyst carried on the wall surface of the heat exchange flow path 73, and an oxidation reaction (combustion reaction) occurs. As a result, combustion heat is generated, and the temperature of the fuel cell body 1 rises. Thus, since the fuel cell main body 1 is heated by the combustion of the unreacted residual hydrogen gas in the fuel cell unit included in the anode gas instead of the electric heating material, the energy utilization efficiency is improved. Further, since the heat exchange channel 73 is formed inside the double-sided separator 5, the combustion heat in the heat exchange channel 73 is not easily transmitted to the outside, and the heat is transmitted to the gas diffusion layers 7 and 8 of the membrane electrode assembly 4. This facilitates the electrochemical reaction between hydrogen gas and oxygen gas in the fuel cell unit heated by the combustion heat.

  Here, when both the anode gas valve 22 and the cathode gas valve 23 are open, the cathode gas flows through the heat exchange flow path 73, but the anode gas does not flow through the heat exchange flow path 73. Therefore, an oxidation reaction does not occur in the heat exchange flow path 73, but heat exchange occurs in the atmosphere by the cathode gas at room temperature. Therefore, the temperature of the fuel cell main body 1 is lowered so as to approach normal temperature.

  Further, when both the anode gas valve 22 and the cathode gas valve 23 are closed, neither the cathode gas nor the anode gas flows through the heat exchange flow path 73.

The controller 80 of the fuel cell main body 1 will be described with reference to FIG.
The controller 80 includes a control unit 101, a DC-DC converter 102, and valve drivers 103 and 104.

  The DC-DC converter 102 converts an input voltage (here, a voltage between the current collector plate 2 and the current collector plate 3) from the fuel cell main body 1, and outputs the converted voltage to an external device.

  The valve driver 103 outputs driving power to the anode gas valve 22 based on the control signal from the control unit 101, and the valve driver 104 outputs driving power to the cathode gas valve 23 based on the control signal from the control unit 101.

  The control unit 101 includes a RAM (Random Access Memory), a ROM (Read Only Memory), and a CPU (Central Processing Unit). A program is stored in the ROM of the control unit 101, and the CPU of the control unit 101 performs processing according to the program using the RAM as a work area. The control unit 101 controls the opening amounts of the anode gas valve 22 and the cathode gas valve 23 by opening and closing the anode gas valve 22 and the cathode gas valve 23 via the valve drivers 103 and 104, or the DC-DC, as instructed by the program. The DC output voltage of the fuel cell body 1 is measured by measuring the input voltage of the converter 102, the DC output current of the fuel cell body 1 is measured by measuring the input current of the DC-DC converter 102, the temperature The temperature of the fuel cell main body 1 is measured by the sensor 60.

  In addition, the output voltage and output current of the fuel cell unit change depending on the temperature, and the ROM of the control unit 101 shows the relationship between the input voltage from the fuel cell unit to be set in the DC-DC converter 102 and the temperature. The represented input voltage / temperature table (A) is stored. The control unit 101 refers to the input voltage / temperature table (A), calculates the input voltage from the temperature measured by the temperature sensor 60, and controls the DC-DC converter 102 so as to obtain the calculated input voltage. The input voltage / temperature table (A) is set so that the input current input to the DC-DC converter 102 does not become an overcurrent.

  The ROM of the control unit 101 stores an opening amount / temperature table (B) representing the relationship between the opening amount to be set in the cathode gas valve 23 and the temperature. The control unit 101 refers to the opening amount / temperature table (B), calculates the opening amount from the temperature measured by the temperature sensor 60, and controls the cathode gas valve 23 so as to obtain the calculated opening amount. Here, in the opening amount / temperature table (B), the relationship between the temperature and the opening amount is such that the opening amount increases as the temperature increases.

  Further, the ROM of the control unit 101 stores an opening amount / temperature / containing hydrogen amount table (C) representing the relationship between the opening amount to be set in the anode gas valve 22, the temperature, and the hydrogen content. The hydrogen content is the amount of hydrogen gas contained in the anode gas that has flowed through the anode gas flow path 71. Here, in the opening amount / temperature / containing hydrogen amount table (C), the opening amount increases in inverse proportion to the temperature, and the opening amount increases in proportion to the containing hydrogen amount.

As shown in the following equation (6), the control unit 101 calculates the hydrogen content per unit time (unit: CCM) from the DC output current of the fuel cell main body 1.
Hydrogen content per unit time = anode gas amount × 0.75 × (1−DC output current / I _max ) (6)
The coefficient 0.75 is a hydrogen molar ratio in the air-fuel mixture when the anode gas reacts according to the 100% electrochemical reaction formula (1) to become a gas mixture of hydrogen and carbon dioxide on the right side.

In formula (6), I _max is the maximum current per unit time that can be taken out when the fuel cell unit generates electricity by causing the electrochemical reaction formula (4) of the fuel cell unit by the hydrogen gas contained in the supplied anode gas. Then, it is obtained by the following equation (7). In the following formula (7), the unit of the anode gas amount is liter per minute.
I _max = anode gas amount (l) × Faraday constant × 2 (ion valence) /22.4 (l / mol) / 60 (sec) / number of fuel cell unit stacks (7)

  The control unit 101 reads the opening amount from the temperature measured by the temperature sensor 60 and the calculated contained hydrogen amount with reference to the opening amount / temperature / containing hydrogen amount table (C), and the read opening. The anode gas valve 22 is controlled so as to be the amount. Since the hydrogen content per unit time is calculated from the DC output current, the opening amount / temperature / hydrogen content table (C) indicates the opening amount, temperature, and DC output current to be set in the anode gas valve 22. Is substantially expressed.

  The ROM of the control unit 101 stores an opening amount / temperature / necessary air amount table (D) representing the relationship between the opening amount to be set in the cathode gas valve 23, the temperature, and the required air amount per unit time. ing. The required air amount is the amount of air per unit time including the amount of oxygen per unit time necessary for burning the hydrogen from the amount of hydrogen contained per unit time. Here, in the opening amount / temperature / necessary air amount table (D), the opening amount increases in proportion to the required air amount.

The control unit 101 calculates the hydrogen content from the direct current output current of the fuel cell main body 1 according to the equation (6), and further calculates the required air amount from the hydrogen content according to the following equation (8). In equation (8), the coefficient 2.5 is the amount of air relative to the amount of oxygen in the air, and the coefficient 1.2 is a margin including surplus oxygen for sufficiently reacting hydrogen.
Necessary air amount = hydrogen content x 2.5 x 1.2 (8)

  Then, the control unit 101 refers to the opening amount / temperature / necessary air amount table (D), calculates the opening amount from the temperature measured by the temperature sensor 60 and the calculated necessary air amount, and determines the calculated opening. The cathode gas valve 23 is controlled so as to be the amount. Since the required air amount is calculated from the hydrogen content and the hydrogen content is calculated from the DC output current, the opening amount / temperature / required air amount table (D) is stored in the cathode gas valve 23. The relationship among the opening amount to be set, temperature, and DC output current is substantially represented.

  Next, the operation of the control unit 101 instructed by the program and the operation of the fuel cell apparatus accompanying the operation of the control unit 101 will be described.

  FIG. 12 is a flowchart showing the flow of operation of the control unit 101 instructed by the program.

  When the cathode gas is supplied to the cathode gas introduction holes 17, 27, 87 and the anode gas is supplied to the anode gas introduction holes 15, 25, 85, as described above, an electrochemical reaction occurs in each membrane electrode assembly 4. As a result, electric power is generated in the fuel cell main body 1 and thermal energy is also generated. As a result, current / voltage is output from the fuel cell main body 1 to the DC-DC converter 102, and the fuel cell main body 1 also generates heat.

  When the anode gas and the cathode gas are supplied to the fuel cell main body 1, the fuel cell main body 1 continues to generate power, but the control unit 101 performs processing as shown in FIG. 12 during power generation of the fuel cell main body 1.

  As shown in FIG. 12, the control unit 101 reads the output of the temperature sensor 60 and measures the temperature T of the fuel cell body 1 (step S1). Then, the control unit 101 compares the measured temperature T with the set threshold temperature T1, the danger threshold temperature T2, and the limit threshold temperature T3 (limit threshold temperature T3> danger threshold temperature T2> set threshold temperature T1) (step S2, step S3, Step S4). Here, the set threshold temperature T1 is an ideal temperature when the fuel cell body 1 generates power, the danger threshold temperature T2 is the lower limit of the temperature range representing danger, and the threshold threshold temperature T3 is This is the lower limit of the temperature range indicating the possibility of destruction. In other words, it means that the fuel cell main body 1 may be destroyed when the temperature is higher than the threshold threshold temperature T3, and it means that the life of the fuel cell main body 1 may be shortened when the temperature is higher than the critical threshold temperature T2.

  As a result of the comparison, when the control unit 101 determines that the measured temperature T is equal to or higher than the limit threshold temperature T3 (step S2: Yes), the control unit 101 determines that the control cannot be performed normally and outputs an error output (step S21). ), The input circuit of the DC-DC converter 102 is disconnected (step S22), the operation of the fuel cell device is stopped, and the standby mode is entered (step S23).

  When the control unit 101 determines that the measurement temperature T is less than the limit threshold temperature T3, it determines whether the measurement temperature T is equal to or higher than the critical threshold temperature T2 (step S3), and determines that the measurement temperature T is equal to or higher than the critical threshold temperature T2. In this case, the control unit 101 fully opens the anode gas valve 22 so that the anode gas containing residual hydrogen flowing through the anode gas flow channel 71 hardly flows into the combustion gas supply flow channel 74 and the heat exchange flow channel 73 and stops hydrogen combustion. The controller 101 reads the input voltage Vs of the DC-DC converter 102 according to the input voltage / temperature table (A) (step S19), and the DC input voltage of the DC-DC converter 102. Is set to the input voltage Vs (step S20). Thereby, the temperature of the fuel cell main body 1 is quickly lowered and the input voltage from the fuel cell main body 1 is set according to the temperature T.

  Even when the fuel cell main body 1 reaches the critical threshold temperature T2 or more, the heat loss of the fuel cell main body 1 can be reduced by reducing the DC input current of the DC-DC converter 102. This can be illustrated in FIG. FIG. 13 is a graph showing the relationship between the output current and output voltage of the fuel cell main body 1 for each temperature of the fuel cell main body 1 (however, the temperature of the fuel cell main body 1 is TX <TY <TZ). As shown in FIG. 13, the output voltage decreases as the output current of the fuel cell main body 1 increases, and the output voltage tends to increase and the output current increase as the temperature increases. If the output voltage of the fuel cell main body 1 at high temperature TZ is 0.4 V, the output current at that time is 0.8 A, and if the theoretical output voltage of the fuel cell main body 1 is 1.23 V, (1.23 −0.4) × 0.8 = 0.664 W heat loss occurs, the fuel cell body 1 is heated, and when the output voltage of the fuel cell body 1 at TZ is 0.62 V, the output current at that time is 0 .4A, (1.23-0.62) × 0.4 = 0.244 W, heat loss is reduced, and heating of the fuel cell body 1 is reduced. In this way, wasteful heating of the fuel cell main body 1 can be suppressed by relatively increasing the input voltage Vs from the fuel cell main body 1 and reducing the generated current from the fuel cell main body 1 to suppress heat loss. .

  If it is determined in step S3 that the measured temperature T is less than or equal to the danger threshold temperature T2, it is subsequently determined whether or not the measured temperature T is equal to or higher than the set threshold temperature T1 (step S4), and the measured temperature T is equal to or higher than the set threshold temperature T1. The control unit 101 fully opens the anode gas valve 22 (step S15), and the control unit 101 reads the opening amount Vb of the cathode gas valve 23 from the measured temperature T with reference to the opening amount / temperature table (B) (step S16). ), The opening amount of the cathode gas valve 23 is set to the opening amount Vb (step S17). After step S17, the process of the control unit 101 returns to step S1.

  As in step S17 described above, the cathode gas supplied from the cathode gas introduction hole 27 flows into the cathode gas supply channel 75 and the heat exchange channel 73. Thus, the anode gas does not flow through the heat exchange channel 73 but the cathode gas, which is air at normal temperature, flows, so that the fuel cell body 1 is air-cooled. Thus, since the cathode gas valve 23 opens with the opening amount Vb appropriate for the measured temperature T based on the opening amount / temperature table (B), the optimum amount of cathode gas flows through the heat exchange flow path 73 and the fuel cell main body. 1 accurate temperature control can be performed.

  When it is determined in step S4 that the measured temperature T is lower than the set threshold temperature T1, the control unit 101 sets the DC-DC converter 102 to the input voltage Vus (step S5). Thereby, the DC-DC converter 102 operates at a constant input voltage, and performs the steps shown below so that the input voltage from the fuel cell main body 1 does not become the input voltage Vus or less.

After a predetermined time has elapsed from step S5, the control unit 101 measures the DC output current I ₀ of the fuel cell main body 1 via the DC-DC converter 102 (step S6). Then, the control unit 101 measures the DC output voltage V ₀ of the fuel cell main body 1 via the DC-DC converter 102 (step S7). Steps S6 and S7 may be reversed in order.

Next, the control unit 101 compares the DC output voltage V ₀ with a predetermined value (here, for example, 0.3 [V] × the number of fuel cell units), and when the DC output voltage V ₀ is equal to or lower than the predetermined value. Is less than the set input voltage Vus of the DC-DC converter 102, the processing of the control unit 101 proceeds to step S21, and the operation of the fuel cell main body 1 is stopped. If the DC output voltage V ₀ exceeds the predetermined value in step S8, the processing of the control unit 101 proceeds to step S9.

In step S9, the control unit 101 calculates the hydrogen content Ch from the DC output current I ₀ according to the above equation (6). Next, the control unit 101 calculates the necessary air amount Na from the hydrogen content Ch according to the above equation (8) (step S10).

  Next, the controller 101 reads the opening amount Vh from the measured temperature T and the contained hydrogen amount Ch calculated in step S9 with reference to the opening amount / temperature / containing hydrogen amount table (C) (step S11). Next, the control unit 101 refers to the opening amount / temperature / necessary air amount table (D) and calculates the opening amount Va from the measured temperature T and the necessary air amount Na (step S12).

  Next, the control unit 101 controls the opening amount of the anode gas valve 22 to the opening amount Vh based on step S11 (step S13), and controls the opening amount of the cathode gas valve 23 to the opening amount Va based on step S12. (Step S14), and then the process of the control unit 101 returns to Step S1.

When the anode gas valve 22 is opened with the opening amount Vh (not fully opened) as in step S13 above, part of the anode gas that has flowed through the anode gas flow path 71 is transferred to the combustion gas supply flow path 74 and the heat exchange flow path 73. Flows in. Further, the cathode gas valve 23 is opened as in step S14 so as to take in the minimum amount of oxygen in consideration of the margin from the hydrogen content Ch in the anode gas calculated from the DC output current I ₀ of the fuel cell body 1. When opened by the amount Va (not completely closed), the cathode gas supplied from the cathode gas introduction hole 27 flows into the cathode gas supply channel 75 and the heat exchange channel 73. As described above, since the amount of oxygen flowing through the heat exchange channel 73 is the minimum necessary, it is possible to suppress a reduction in the temperature in the heat exchange channel 73 due to room temperature oxygen, and the mixture of anode gas and cathode gas is a heat exchange flow. An oxidation reaction (combustion reaction) takes place through the action of the combustion catalyst in which the hydrogen gas and the oxygen gas are carried on the wall surface of the heat exchange passage 73 through the passage 73.

  Here, the flow rate of the cathode gas flowing into the heat exchange flow path 73 depends on the opening amount Va of the cathode gas valve 23. That is, as the opening amount Va increases, the flow rate of the cathode gas flowing from the cathode gas introduction hole 27 to the heat exchange flow path 73 increases. The flow rate of the anode gas flowing from the anode gas channel 71 to the heat exchange channel 73 depends on the opening amount Vh of the anode gas valve 22. That is, as the opening amount Vh increases, the flow rate of the anode gas flowing from the anode gas channel 71 to the heat exchange channel 73 decreases.

  As described above, the control unit 101 calculates the amount of hydrogen gas in the anode gas from the DC input current of the DC-DC converter 102 in accordance with the temperature of the fuel cell main body 1 and further burns it. The amount of cathode gas is calculated, each valve 22, 23 is controlled, only the cathode gas at normal temperature is sent to the heat exchange flow path 73 to cool the fuel cell body 1, or the direct current of the DC-DC converter 102 By increasing the input voltage (setting the DC input voltage to the input voltage Vs), the DC input current is reduced and the temperature of the fuel cell main body 1 is controlled, thereby suppressing the heat generation of the fuel cell main body 1 itself. The temperature control of the battery body 1 can be realized efficiently.

  The present invention is not limited to the above embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.

[Modification 1]
In the above embodiment, in step S1, the temperature of the fuel cell main body 1 is directly measured by the temperature sensor 60 provided in the fuel cell main body 1. However, the fuel from the DC input current or DC input voltage of the DC-DC converter 102 is measured. The temperature T of the battery body 1 may be obtained. That is, as shown in FIG. 13, since the current-voltage characteristic of the fuel cell main body 1 depends on the temperature, the temperature T of the fuel cell main body 1 is obtained from the DC input current and DC input voltage of the DC-DC converter 102. Can do. When the DC input voltage of the DC-DC converter 102 is set to be constant, the temperature T of the fuel cell body 1 can be obtained from the DC input current of the DC-DC converter 102.

[Modification 2]
In the above embodiment, the valves 22 and 23 provided in the fuel cell main body 1 are electrically operated, but may be thermally operated. That is, the valves 22 and 23 are not a piezoelectric element type but a bimetal type or a shape memory alloy type. When the temperature of the fuel cell body 1 is equal to or lower than the set temperature, the bimetal type or shape memory alloy type valve 22 is closed, and the anode gas that has flowed through the anode gas flow path 71 flows into the heat exchange flow path 73, thereby burning The temperature of the fuel cell body 1 rises due to heat. On the other hand, when the temperature of the fuel cell main body 1 exceeds the set temperature, the valve 22 is opened, and the anode gas that has flowed through the anode gas flow path 71 does not flow into the heat exchange flow path 73, so that no combustion heat is generated.

[Modification 3]
A check valve may be provided in at least one of the middle part of the long groove 35 and the long groove 36, and the gas flow from the anode gas discharge hole 26 toward the perforation 33 may be blocked by these check valves. Further, a check valve may be provided in at least one of the middle portions of the long groove 40 and the long groove 43, and the flow of gas from the junction 38 to the cathode gas introduction hole 27 may be blocked by these check valves. Further, a check valve may be provided in the middle of the combustion gas supply flow path 74 and the flow of gas from the branch point toward the perforation 33 may be blocked by this check valve.

[Modification 4]
In the above embodiment, the anode gas discharge holes 16, 26, 86 and the cathode gas discharge holes 18, 28, 88 are separate, but they may also serve as the same discharge hole. For example, the terminal end of the cathode gas flow path 76 may not communicate with the cathode gas discharge hole 28 but may communicate with the anode gas discharge hole 26, and conversely, the anode gas discharge flow path 72 and the heat exchange flow path 73. Instead of communicating with the anode gas discharge hole 26, the end of each may communicate with the cathode gas discharge hole 28.

[Modification 5]
In the above embodiment, hydrogen is reformed and supplied to the fuel cell body 1. However, the present invention is not limited to this, and fuel such as methanol can be supplied without providing the vaporizer 203, the reformer 204, and the carbon monoxide remover 205. You may use for the direct fuel cell which supplies the fuel cell main body 1 and generates electric power.

2 is a block diagram of a power generation device 200. FIG. 1 is a cross-sectional view of a fuel cell main body 1. 3 is a plan view of the membrane electrode assembly 4. FIG. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. 3 is a plan view of one surface of a double-sided separator 5. FIG. 4 is a plan view of the other surface of the double-sided separator 5. FIG. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 5. 3 is a plan view of a metal plate 21. FIG. 2 is a plan view of a metal plate 20. FIG. 3 is a plan view of a metal plate 19. FIG. 2 is a block diagram of a controller 80. FIG. It is a flowchart of operation | movement of the controller 80 according to a program. 3 is a graph showing the relationship between the output current and output voltage of the fuel cell main body 1 for each temperature of the fuel cell main body 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fuel cell main body 4 ... Membrane electrode assembly 5 ... Double-sided separator 6 ... Solid polymer electrolyte membrane 7, 8 ... Gas diffusion layer 22 ... Anode gas valve 23 ... Cathode gas valve 25 ... Anode gas introduction hole 26 ... Anode gas discharge hole 27 ... cathode gas introduction hole 28 ... cathode gas discharge hole 33 ... perforation 71 ... anode gas flow path 72 ... anode gas discharge flow path 73 ... heat exchange flow path 74 ... combustion gas supply flow path 75 ... cathode gas supply flow path 76 ... cathode Gas flow path 80 ... Controller 101 ... Control unit 102 ... DC-DC converter

Claims (14)

An anode gas flow path through which the anode gas flows is provided on one side,
Having a cathode gas flow path through which the cathode gas flows on the other surface;
Having an internal flow channel communicating with the anode gas flow channel and communicating with the cathode gas flow channel between the one surface and the other surface;
A fuel cell separator comprising a combustion catalyst on a wall surface of the internal flow path.   2. The fuel cell separator according to claim 1, wherein the internal flow path communicates with a terminal portion of the anode gas flow path. A cathode gas introduction hole for introducing the cathode gas;
3. The fuel cell separator according to claim 1, wherein the internal channel and the cathode gas channel communicate with each other through the cathode gas introduction hole. An anode gas discharge hole for discharging the anode gas;
An anode gas discharge channel communicating from the terminal end of the anode gas channel to the anode gas discharge hole;
4. The fuel cell separator according to claim 1, further comprising an anode gas valve that adjusts an opening amount of the anode gas discharge passage in a middle portion of the anode gas discharge passage. 5.   The internal flow path is a combustion gas flow path that communicates from the terminal portion of the anode gas flow path to the merge section, a cathode gas supply flow path that communicates from the cathode gas flow path to the merge section, and the merge section The fuel cell separator according to claim 4, further comprising a heat exchange passage communicating with the anode gas discharge hole.   6. The fuel cell separator according to claim 5, further comprising a cathode gas valve for adjusting an opening amount of the cathode gas supply channel in a middle portion of the cathode gas supply channel. A fuel cell device comprising: a membrane electrode assembly having a solid polymer electrolyte membrane and a pair of gas diffusion layers facing each other across the solid polymer electrolyte membrane; and separators stacked alternately with the membrane electrode assembly Because
The separator has an anode gas flow path through which the anode gas flows on one side, a cathode gas flow path through which the cathode gas flows on the other side, and communicates with the anode gas flow path and the cathode gas flow path A fuel cell device comprising an internal flow passage communicating with the inside of the space between the one surface and the other surface, and a combustion catalyst on a wall surface of the internal flow passage.   The fuel cell device according to claim 7, wherein the internal flow path communicates with a terminal portion of the anode gas flow path. The separator has a cathode gas introduction hole for introducing a cathode gas;
The fuel cell device according to claim 7 or 8, wherein the internal flow path and the cathode gas flow path communicate with each other through the cathode gas introduction hole. The separator has an anode gas discharge hole for discharging the anode gas;
An anode gas discharge channel that communicates from the terminal end of the anode gas channel to the anode gas discharge hole, and an anode gas valve that adjusts an opening amount of the anode gas discharge channel is provided in the middle of the anode gas discharge channel The fuel cell device according to claim 7, wherein the fuel cell device is provided in the fuel cell device.   The internal flow path is a combustion gas flow path that communicates from the terminal portion of the anode gas flow path to the merge section, a cathode gas supply flow path that communicates from the cathode gas flow path to the merge section, and the merge section The fuel cell device according to claim 10, further comprising a heat exchange flow path communicating with the anode gas discharge hole.   12. The fuel cell device according to claim 11, wherein the separator has a cathode gas valve for adjusting an opening amount of the cathode gas supply channel in a middle portion of the cathode gas supply channel. A DC-DC converter for inputting power generated by the membrane electrode assembly;
The fuel cell device according to claim 12, further comprising: a control unit that measures an input current of the DC-DC converter and controls an opening amount of the anode gas valve according to the input current.   The fuel cell device according to claim 13, wherein the control unit controls an opening amount of the cathode gas valve in accordance with an input current of the DC-DC converter.

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