JP4501540B2 - Fuel cell - Google Patents

Description

  The present invention relates to a fuel cell, and more particularly to a solid oxide fuel cell operated at a high temperature.

  As a conventional solid oxide fuel cell (SOFC), for example, there is one described in Patent Document 1 below, which is roughly classified into a flat plate type and a cylindrical type. Of these, the flat plate type, which is said to be easy to increase the output density, is further broadly divided into a square type and a disk type, and the disc type has no singular points where thermal stress is concentrated, so the stress is dispersed. Many types of research institutes are investigating a type in which a large number of disk-shaped cells are stacked.

On the other hand, in the case of a structure that holds one end for supplying gas, the cylindrical type is resistant to thermal stress because thermal deformation is allowed in the length direction, and is a high-temperature operation type of about 1000 ° C. as a representative example of Westinghouse. Fuel cells are most practically used.
JP-A-6-243879

  However, even if the flat plate type is a disk type that is resistant to thermal stress, temperature unevenness is likely to occur during high-speed startup, and the electrolyte, interconnector, separator, etc. are distorted. Anxiety such as entering is not wiped out.

  In this case, it is possible to escape from destruction caused by deformation due to relatively stress if a structure in which the stacked flat disks are not firmly fixed to each other, but conversely, even with slight deformation, the interconnect For this reason, the uniformity of contact is impaired, and the strength of the disk must be ensured as in the case of Sulzer, so the packing density cannot be increased, and it is difficult to increase the output per volume.

  In addition, it is known that a large cylindrical type is easy to manufacture, but because there is a difference in gas concentration in the longitudinal direction, there is a difference in electromotive force according to the gas concentration difference, and power is consumed internally. ing.

  On the other hand, in the invention described in Patent Document 1, a plurality of tapered tube-type cells are connected in the axial direction to improve mechanical strength and gas sealing properties. Therefore, there is a lot of wasted space and it is difficult to increase the output density.

  In addition, when a large number of cylindrical fuel cells are packed in a casing at a high density, it is not easy to connect a gas supply system, and thus it is difficult to pack a cylindrical fuel cell in a casing at a high density. It is difficult to increase the volumetric power density.

  Therefore, an object of the present invention is to increase the output density while preventing deformation due to thermal stress without using a rigid member.

The present invention is a fuel cell using a solid oxide fuel cell as a power generation cell, comprising an electrolyte and a pair of electrodes on both sides on the outer periphery of a cell-side gas distribution member having two gas flow paths. A power generation cell having a taper portion inclined at a predetermined angle with respect to the cell side gas distribution member is provided to form a cell unit, and the separator is disposed on the outer periphery of the separator side gas distribution member having the two gas flow paths. Providing a separator having a tapered portion inclined at a predetermined angle with respect to the side gas distribution member to form a separator unit, laminating a large number of the cell unit and the separator unit as a set, and the power generation cell and the A conductive interconnector is interposed between the separator and each gas channel of the two systems and each interconnect on both sides of the electrolyte in the power generation cell. The most important feature is that the two gas systems are separately supplied to the interconnector installation areas by separately connecting the Kuta installation areas to the interconnector installation areas.

  According to the present invention, since the power generation cell and the separator are provided with the tapered portion, the strength against thermal deformation is improved and the reliability is improved. In addition, a large number of cell units and separator units are stacked, and a conductive interconnector is interposed between the power generation cell and the gas separator, enabling stable electrical connection. In addition to improving the power generation efficiency, the power generation cell and gas separator are tapered, so the power generation area becomes larger than the diameter, and the cell unit and separator unit can be stacked to reduce wasteful space. Thus, the output density can be increased.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a solid oxide fuel cell showing a first embodiment of the present invention. In this fuel cell, a separator unit 1 shown in FIG. 2 (a) and a cell unit 3 shown in FIG. 2 (b) are combined as a set, and a large number of these are stacked. , 7 and is fastened by bolts 9 and nuts 11 penetrating the center. At this time, a concave portion 5 a is formed in the center portion of the upper fixing member 5 in the stacking direction, and a disc spring 13 is interposed between the concave portion 5 a and the nut 11. The disc spring 13 is provided with a plurality of through holes 13a that communicate with a gas flow path 15 described later along the circumferential direction.

  The fixing member 5 includes a tapered surface 5b that protrudes downward in FIG. 1 in accordance with a later-described taper portion of the separator unit 1, and the fixing member 7 is illustrated in accordance with a later-described taper portion of the cell unit 3. 1 is provided with a tapered surface 7a which is concave at the top.

  A gas flow path 15 for inserting the bolt 9 described above is formed in the center portion of the laminated body so as to penetrate in the vertical direction. As shown in FIG. 1, the gas flow path 15 communicates with a recess 5a formed in the upper fixing member 5, and supplies hydrogen gas as a fuel gas to the gas flow path 15 through the recess 5a.

  On the outer peripheral side of the gas flow path 15, another gas flow path 17 is formed penetrating in the vertical direction. The gas flow path 17 communicates with a gas introduction hole 7a formed in the lower fixing member 7 and supplies air as an oxidant gas through the gas introduction hole 7a.

  As shown in FIG. 2A, the separator unit 1 includes, for example, a disk-shaped separator-side gas distribution member 19 having a diameter of 50 mm, for example, and a separator 21 having a thickness of, for example, about 100 μm, which is joined to the upper part. Both are made of a conductive refractory metal such as SUS430. The separator-side gas distribution member 19 includes a through hole 19a that forms the gas flow path 15 at the center, and a through hole 19b that forms the gas flow path 17 on the side. The through hole 19b is formed with a communication hole 19c that opens to the outer peripheral surface.

  FIG. 3A is a plan view of the separator-side gas distribution member 19 described above. Four through holes 19b and four communication holes 19c are provided at equal intervals in the circumferential direction, and a through hole 23b of the separator 25 described later. Are also provided corresponding to the through holes 19b.

  On the other hand, the separator 21 has a disk portion 23 as a flat plate portion integrated with the upper portion of the cell-side gas distribution member 19 by diffusion bonding, and an inner peripheral edge portion continuous with an outer peripheral edge portion of the disk portion 23, and the outer peripheral side is closer to FIG. A conical tapered portion 25 is provided to be an upper portion. That is, the separator 21 includes a tapered portion 25 that is inclined at a predetermined angle with respect to the separator-side gas distribution member 19.

  The disk portion 23 is formed in the separator-side gas distribution member 19 in the same manner as the through-hole 23a that constitutes the gas flow path 15 in alignment with the through-hole 19a formed in the separator-side gas distribution member 19 described above. A through-hole 23b that constitutes the gas flow path 17 is provided in alignment with the through-hole 19b.

  As shown in FIG. 2B, the cell unit 3 includes a disk-shaped cell-side gas distribution member 27 having the same outer shape as the separator-side gas distribution member 19 and an electrolyte 29 bonded to the upper portion thereof. The cell-side gas distribution member 27 is made of a conductive heat-resistant metal such as SUS430, and has a through hole 27a that constitutes the gas flow path 15 at the center, and the gas flow path 17 at the side. A through-hole 27b is provided. The through hole 27a is formed with a communication hole 27c that opens to the outer peripheral surface.

  FIG. 3B is a plan view of the cell-side gas distribution member 27 described above. Four through holes 27b and four communication holes 27c are provided at equal intervals in the circumferential direction, and a through hole 31b of the electrolyte 29 described later is provided. Similarly, four are provided corresponding to the through holes 27b.

  The electrolyte 29 is an electrolyte made of zirconia doped with scandia (ScSZ), for example, fired to a thickness of 100 μm, and the central disk portion 31 is joined to the cell side gas distribution member 27 by Au brazing, Insulation with respect to the separator-side gas distribution member 19 and gas sealing properties in the stacking direction are ensured. That is, here, the electrolyte 29 is an electrical insulating material.

  The outer peripheral edge of the disk portion 31 in the electrolyte 29 is integrally provided with a conical tapered portion 33 such that the inner peripheral edge is continuous and becomes the upper part in FIG. That is, the electrolyte 29 includes a tapered portion 33 that is inclined at a predetermined angle with respect to the cell-side gas distribution member 27.

  The disk portion 31 has a through-hole 31a that forms the gas flow path 15 in alignment with the through-hole 27a formed in the cell-side gas distribution member 27, and a through-hole that is also formed in the cell-side gas distribution member 27. A through-hole 31b that constitutes the gas flow path 17 is provided in alignment with the hole 27b.

  It should be noted that the laminated interfaces of the cell-side and separator-side gas distribution members 27 and 19 described above have gas-seal properties, and this gas seal is possible by applying them together while applying a ceramic adhesive. .

  As shown in FIG. 2B, an air electrode 35 is formed on the upper surface side of the tapered portion 33 of the electrolyte 29, and a fuel electrode 37 is formed on the lower surface side thereof by firing. On the air electrode 35 and the fuel electrode 37, current collectors 39 and 41 constituting a porous and flexible conductive interconnector are arranged, respectively. The electrolyte 29, the air electrode 35, and the fuel electrode 37 constitute a power generation cell.

  At this time, as shown in FIG. 1, a space 30 is provided between the current collector 39 and the separator-side gas distribution member 19 so as to communicate with the gas flow path 17 through the communication hole 19c. And a cell side gas distribution member 27 is provided with a space 40 communicating with the gas flow path 15 through the communication hole 27c.

  In FIG. 1, the air electrode 35 and the fuel electrode 37 are omitted for simplification.

  In the fuel cell described above, as shown in FIG. 1, the hydrogen gas supplied to the gas flow path 15 from the top in the drawing passes through the communication hole 27c of the cell side gas distribution member 27, passes through the space 40, and the fuel electrode 37. Into the installation area of the side interconnector 41. On the other hand, the air supplied to the gas flow path 17 from the lower part in FIG. 1 passes through the communication hole 19 c and flows into the installation area of the interconnector 39 on the air electrode 35 side through the space 30.

  In this manner, by supplying the fuel electrode 37 and the air electrode 35 on both sides of the electrolyte 29 with the hydrogen gas as the fuel and the air as the oxidant gas, electricity is generated as a fuel cell.

  In such a fuel cell according to the present embodiment, the outer peripheral sides of the electrolyte 29 constituting the power generation cell in the cell unit 3 and the separator 21 in the separator unit 1 are formed as the conical tapered portion 33 and the tapered portion 25, respectively. The strength against thermal deformation is improved and the reliability is improved.

  A large number of cell units 3 and separator units 1 are stacked, and a porous and flexible conductive current collector 39, between the power generation cell and the tapered portion 25 of the separator 21, By interposing 41, stable electrical connection is possible and the power generation efficiency is improved, and the above-mentioned conical shape increases the power generation area for the entire diameter, so that the cell unit 3 and the separator unit 1 In combination with the possibility of stacking, the useless space is reduced and the output density can be increased.

  Further, in the flat type fuel cell, if it is attempted to configure the gas distribution member at the center portion in accordance with the power generation cell where the layer thickness is desired to be as thin as possible, processing becomes very difficult. The thickness of each of the gas distribution members 19 and 27 on the cell side and the separator side can be increased and the cross section of the gas flow path can be increased, so that the manufacture is facilitated.

  Further, since the fixing members 5 and 7 at both the upper and lower ends in FIG. 1 have the taper surfaces 5b and 7a in contact with the separator unit 1 and the cell unit 3, respectively, have the same inclination angle as the taper portions 25 and 33, the separator unit 1 and By laminating a large number of cell units 3 and fastening them with bolts 9 and nuts 11, it is possible to apply an effective lamination pressure to the conical portion without excessively tightening the fastening force and making the whole connection. Since the current collecting performance can be secured while securing the strength, not only the power generation efficiency is high, but also the output fluctuation due to vibration is reduced.

  Spaces 40 and 30 communicating with the two gas flow paths 15 and 17 are provided between the current collectors 41 and 39 and the gas distribution members 27 and 19 on the cell side and the separator side, respectively. Therefore, the spaces 40 and 30 serve as gas distribution chambers, and two gases from the center can be uniformly distributed to the reaction system from the spaces 40 and 30 serving as gas distribution chambers. Can be increased. Further, when the spaces 40 and 30 are provided, no special processing is required, and the cost is reduced.

  FIG. 4 is a cross-sectional view of the separator unit 1 and the cell unit 3 corresponding to FIG. 2, showing a second embodiment of the present invention. This embodiment is the same as FIG. 2A for the separator unit 1 shown in FIG. Therefore, only the cell unit 3 shown in FIG.

The cell unit 3 shown in FIG. 4B joins the inner peripheral edge of a metal foil 43 as a conical metal plate to the outer peripheral edge of the cell- side gas distribution member 27 by welding, and shows the metal foil 43 in FIG. The fuel electrode 37, the electrolyte 45, and the air electrode 35 are formed in this order on the upper surface side. A current collector 39 is disposed on the upper surface of the air electrode 35, and a current collector 41 is disposed on the opposite side of the metal foil 43 from the fuel electrode 37.

  That is, in this embodiment, the separator 21 and the separator-side gas distribution member 19 are electrically connected, and one of the pair of electrodes (fuel electrode 37) of the power generation cell is connected to the cell-side gas distribution member 27 with the metal foil 43. And the other electrode (air electrode 35) is electrically insulated from the cell-side gas distribution member 27.

  An electrically insulating layer 47 having airtightness is provided between the cell-side gas distribution member 27 and the separator-side gas distribution member 19 that are electrically insulated from the air electrode 35. The electrical insulating layer 47 includes a through hole 47 a that matches the through hole 19 a of the separator side gas distribution member 19 and a through hole 47 b that matches the through hole 19 b of the separator side gas distribution member 19.

  Also in the second embodiment described above, the same effects as in the first embodiment can be obtained.

  In the first embodiment described above, the disk portion 31 of the electrolyte 29 constitutes the electrical insulating layer 47 in the second embodiment described above.

  FIG. 5 is a modification of the embodiment of FIG. 4, in which the inner peripheral edge of the conical metal foil 43 is joined to the outer peripheral edge of the cell-side gas distribution member 27 by welding, and the lower surface of the metal foil 43 in FIG. On the side, an air electrode 35, an electrolyte 45, and a fuel electrode 37 are formed in this order. A current collector 41 is disposed on the lower surface of the fuel electrode 37, and a current collector 39 is disposed on the opposite side of the metal foil 43 from the air electrode 35.

  In this example, contrary to the example of FIG. 4, the air electrode 35 is electrically connected to the cell-side gas distribution member 27 via the metal foil 43, and the fuel electrode 37 is electrically connected to the cell-side gas distribution member 27. Is electrically insulated. Therefore, here, the electrical insulating layer 47 is disposed on the lower side of the cell-side gas distribution member 27 in FIG.

FIG. 6 is a sectional view showing only the right half of the separator unit 1 and the cell unit 3 corresponding to FIG. 2, showing the third embodiment of the present invention. In this embodiment, any one of the separator 49 and the air electrode 35 and the fuel electrode 37 which are a pair of electrodes of the power generation cell is electrically connected to the separator-side gas distribution member 19 or the cell-side gas distribution member 27. The other two gas distribution members and the other gas distribution members are electrically connected to each other, and the other two gas distribution members are electrically insulated. Either one is provided.

In this embodiment, there are three combinations shown in Table 1 shows collectively the three combination example in FIG.

As a combination (1), the separator 49 and the separator-side gas distribution member 19 are electrically connected (P), and the other two electrodes, that is, the air electrode 35 and the fuel electrode 37 are electrically connected to the cell-side gas distribution member 27. Insulate. In this case, an electrically insulating material A, is placed on top of the separator-side gas distribution member 19 in FIG. 6.

As combination (2), the air electrode 35 and the cell side gas distribution member 27 are electrically connected (Q), and between the separator 49 and the separator side gas distribution member 19, and between the fuel electrode 37 and the cell side gas distribution member. 27 are electrically insulated from each other. In this case, an electrically insulating material B, and disposed below the separator-side gas distribution member 19 in FIG. 6.

As a combination (3), the fuel electrode 37 and the cell side gas distribution member 27 are electrically connected (R), and between the separator 49 and the separator side gas distribution member 19, and between the air electrode 35 and the cell side gas distribution member. 27 are electrically insulated from each other. In this case, an electrically insulating material C, and placed in the lower part of the cell side gas distribution member 27 in FIG. 6.

FIG. 7 is a cross-sectional view showing only the right half of the separator unit 1 and the cell unit 3 corresponding to FIG. 2, showing the fourth embodiment of the present invention. In this embodiment, the separator unit 1 is configured such that the separator 55 has a shape having only a conical taper portion, and the outer peripheral side of the conical metal foil 59 is bonded to the inner peripheral edge portion via an insulating adhesive 57. The end on the inner peripheral side of the metal foil 59 is joined to the separator-side gas distribution member 19 by welding.

  On the other hand, the cell unit 3 sandwiches the inner peripheral side end portion of the conical electrolyte 45 with the outer peripheral side end portions of the two conical metal foils 61 and 63 serving as the metal plates. The inner peripheral side end portions are joined to the outer peripheral portion of the cell-side gas distribution member 27 by welding in a state of being butted against each other.

  That is, in this embodiment, the separator 55 and the separator-side gas distribution member 19 are electrically insulated, and the air electrode 35 and the fuel electrode 37 and the cell-side gas distribution member 27 in the power generation cell are electrically insulated. .

According to the fourth embodiment described above, when the laminated structure of the separator-side gas distribution member 19 and the cell-side gas distribution member 27 in the center portion is used, it is not necessary to take electrical insulation and gas sealing at the same time, only gas sealing. Therefore, the gas distribution members 19 and 27 can adopt a gas seal structure that is easy to assemble such as forming a groove between the gas distribution members 19 and 27, thereby facilitating the stacking assembly process and reducing the cost. Can do.

  The metal foils 61 and 63 described above have a conical shape, and the conical electrolyte 45 is sandwiched and connected by the two metal foils 61 and 63, so that the metal foils 61 and 63 and the electrolyte 45 are connected at this connecting portion. It is firmly fixed.

Here, when a gas seal is secured between the front and back surfaces of the electrolyte 45, as shown in FIG. 8 , even when the glass or adhesive 65 is filled between the two metal foils 61 and 63, the glass or adhesive is used. There is no need to require adhesive strength for the agent 65, and the assembly becomes extremely simple.

As shown in FIG. 9 , the separator 55 can also be sandwiched between two metal foils 67 and 69 through a glass 71 serving as an electrical insulating material. The connection strength can be improved.

  According to the present invention, the separator and the separator-side gas distribution member are electrically connected, and one of the pair of electrodes of the power generation cell is electrically connected to the cell-side gas distribution member. The other of the pair of electrodes of the power generation cell is electrically insulated from the cell-side gas distribution member, and the air-tightness is provided between the cell-side gas distribution member and the separator-side gas distribution member on the other electrode side. Since the electrically insulating layer having the above is provided, the electrically insulating state can be ensured while ensuring the gas sealing property.

  The separator includes a flat plate portion that is joined to the separator-side gas distribution member in a stacked state, and a tapered portion that extends outward from an outer peripheral edge portion of the flat plate portion, and the power generation cell includes the one electrode and the Since the cell-side gas distribution member is connected to the cell-side gas distribution member, the connection of the one electrode to the cell-side gas distribution member can be strengthened while electrically connecting one electrode to the cell-side gas distribution member. it can.

  Since the separator and the separator-side gas distribution member are electrically insulated, and the electrodes of the power generation cell and the cell-side gas distribution member are electrically insulated, the separator-side gas distribution member at the center It is not necessary to take electrical insulation and gas sealing at the same time when configuring the laminated body with the cell-side gas distribution member, and only gas sealing needs to be considered, and the laminating and assembling process becomes easy and the cost can be reduced.

  Since the separator is connected to the separator-side gas distribution member with an insulating adhesive, and the electrolyte serving as an electrical insulating layer and the cell-side gas distribution member are connected via a metal plate, the separator and the separator It is possible to electrically insulate between the side gas distribution member and between each electrode on both sides of the power generation cell and the cell side gas distribution member.

  The metal plate is composed of two metal foils, and one end of each metal foil is joined to the cell side gas distribution member while abutting each other, and the other end is connected so as to sandwich the electrolyte from both sides. Therefore, the metal foil and the electrolyte can be firmly fixed at this connection portion.

  The cell-side and separator-side gas distribution members are superposed on each other with the same outer shape, and the power generation cell and the separator are superposed on each other with the inclination angles of the respective taper portions being the same angle. And since the laminated body in which a large number of these separator units are laminated as a set is pressed from both ends and fastened, an effective laminating pressure can be applied to the conical portion without excessive fastening force. The current collecting performance can be ensured while ensuring the coupling strength, and not only the power generation efficiency is high but also the output fluctuation due to vibration is reduced.

  Between the interconnector and each of the cell-side and separator-side distribution members, a space communicating with each of the two gas flow paths is provided, and this space becomes a gas distribution chamber. Gas can be uniformly distributed to the reaction system from each space serving as a gas distribution chamber, and power generation efficiency can be increased. Further, in this case, no special processing is required when providing the space, and the cost is reduced.

1 is a cross-sectional view of a solid oxide fuel cell showing a first embodiment of the present invention. (A) is sectional drawing of the separator unit in the fuel cell of FIG. 1, (b) is sectional drawing of the cell unit. (A) is a top view of the separator side gas distribution member in the fuel cell of FIG. 1, (b) is a top view of the cell side gas distribution member. It is sectional drawing of the separator unit and cell unit equivalent to FIG. 2 which shows the 2nd Embodiment of this invention. It is sectional drawing of the cell unit corresponding to FIG.4 (b) which shows the modification of FIG. It is sectional drawing which shows only the right half of the separator unit and cell unit which correspond to FIG. 2, which shows the 3rd Embodiment of this invention. It is sectional drawing which shows only the right half of the separator unit and cell unit corresponding to FIG. 2 which shows the 4th Embodiment of this invention. Is a sectional view showing an example filled with the glass between the metal foil each other in the cell unit of FIG. Ru sectional view showing an example in which sandwich the separator two metal foils in the separator unit of Fig.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Separator unit 3 Cell unit 15, 17 Gas flow path 19 Separator side gas distribution member 21, 49, 55 Separator 23 Disc part (flat plate part) of separator
25 Tapered portion of separator 27 Cell side gas distribution member 29,45 Electrolyte (power generation cell)
31 Electrolyte disk (electrical insulation layer)
30, 40 Space communicating with gas flow path 35 Air electrode (electrode, power generation cell)
37 Fuel electrode (electrode, power generation cell)
39, 41 Current collector (interconnector)
43, 61, 63 Kinzo foil (metal plate)
47, A, B, C Electrical insulating layer 57 Insulating adhesive

Claims (10)

A fuel cell using a solid oxide fuel cell as a power generation cell,
Provided on the outer periphery of the cell side gas distribution member having two gas flow paths is a power generation cell provided with an electrolyte and a pair of electrodes on both sides thereof and having a tapered portion inclined at a predetermined angle with respect to the cell side gas distribution member The separator unit is provided with a separator having a tapered portion inclined at a predetermined angle with respect to the separator-side gas distribution member on the outer periphery of the separator-side gas distribution member having the two gas flow paths. The cell unit and the separator unit are stacked as a set, and a conductive interconnector is interposed between the power generation cell and the separator, so that each gas flow of the two systems In this state, each interconnector is installed in a separate communication state between the road and each interconnector installation region on both sides of the electrolyte in the power generation cell. Fuel cell, wherein said that the gas of two systems to be supplied separately to the region.   The separator and the separator-side gas distribution member are electrically connected, and one of the pair of electrodes of the power generation cell is electrically connected to the cell-side gas distribution member, and the pair of power generation cells The other of the electrodes is electrically insulated from the cell side gas distribution member, and an electrically insulating layer having airtightness is provided between the cell side gas distribution member and the separator side gas distribution member on the other electrode side. The fuel cell according to claim 1, further comprising:   The separator includes a flat plate portion that is joined to the separator-side gas distribution member in a stacked state, and a tapered portion that extends outward from an outer peripheral edge portion of the flat plate portion, and the power generation cell includes the one electrode and the 3. The fuel cell according to claim 2, wherein the cell side gas distribution member is connected by a metal plate.   2. The fuel according to claim 1, wherein the separator and the separator-side gas distribution member are electrically insulated, and each electrode of the power generation cell and the cell-side gas distribution member are electrically insulated. battery.   The separator is connected to the separator-side gas distribution member with an insulating adhesive, and the electrolyte serving as an electrical insulating layer is connected to the cell-side gas distribution member via a metal plate. The fuel cell according to claim 4.   The metal plate is composed of two metal foils, and one end of each metal foil is joined to the cell side gas distribution member while abutting each other, and the other end is connected so as to sandwich the electrolyte from both sides. 6. The fuel cell according to claim 5, wherein The cell-side and separator-side gas distribution members are overlapped with each other with the same outer shape, and the power generation cell and the separator are overlapped with each other with the inclination angles of the respective taper portions being the same angle. The fuel cell according to any one of claims 1 to 6 , wherein a laminate obtained by laminating a plurality of the separator units as a set is pressed from both ends and fastened. 8. The space according to claim 1 , wherein a space communicating with each of the two gas flow paths is provided between the interconnector and each of the cell-side and separator-side distribution members. The fuel cell as described. The outer peripheral edge of the cell- side gas distribution member is connected to the inner peripheral edge of the conical metal foil in which a fuel electrode, an electrolyte, and an air electrode are arranged in this order on the upper surface as the power generation cell by welding. The fuel cell according to claim 1. The outer peripheral edge of the cell-side gas distribution member and a conical metal foil in which an air electrode, an electrolyte, and a fuel electrode are arranged in this order on the lower surface as the power generation cell are connected by welding. A fuel cell according to claim 1.