JP2013168227A - Method of manufacturing solid oxide fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a solid oxide fuel cell which allows reduction in cost.SOLUTION: The thickness of a collector member 14 prior to assembling is equal to or more than three times the degree of warpage of a unit cell 11. The thickness of the collector member 14 is also greater than a value obtained by subtracting the thickness of the unit cell 11 from a distance between the bottom face of a recess 121 and an air electrode interconnector 13, when in a state where a fuel electrode interconnector 12 and the air electrode interconnector 13 are assembled together. Consequently, fuel gas can be evenly supplied to the unit cell 11 without providing a groove or projection on the interconnector as in a conventional case. This significantly cuts down the cost of manufacturing the interconnectors, thereby allowing reduction in cost.

Description

  The present invention relates to a method for manufacturing a flat plate type solid oxide fuel cell including a flat plate type single cell and an interconnector that accommodates the single cell.

  A flat cell electrode, an electrolyte layer made of a solid oxide formed on the fuel electrode, and an air electrode formed on the electrolyte layer form a single cell, and a fuel gas and an oxidant are formed on the fuel electrode and the air electrode. Conventionally known is a solid oxide fuel cell (SOFC) that generates electricity using the reverse reaction of water electrolysis by supplying a gas and causing an oxidation-reduction reaction. . Such solid oxide fuel cells have high energy conversion efficiency and can generate power with reduced carbon dioxide emissions, and are therefore being actively developed by many research institutions.

  When actually operating a single cell as a fuel cell, in order to obtain a practically sufficient amount of power generation, the single cells are stacked (stacked) and connected in series, with the fuel electrode side in a reducing atmosphere and the air electrode side In addition to maintaining the oxidizing atmosphere, it is necessary to keep the fuel cell body at a high temperature of about 800-1000 ° C. in which the ionic conductivity of the electrolyte is ensured and an electrochemical reaction easily occurs in order to obtain sufficient power generation efficiency. In order to achieve this, the fuel electrode and the air electrode exposed to different atmospheres are electrically connected by gas-impermeable and electrically conductive parts, and fuel gas and oxidant gas are respectively connected to each electrode. An interconnector (separator) made of metal is arranged between each single cell for the purpose of proper distribution and supply. In addition, a current collecting member made of metal is disposed between the single cell and the interconnector to ensure the electrical connection between them. A single cell stack including a single cell, an interconnector that accommodates the single cell, and a current collecting member disposed between the single cell and the interconnector is stacked, and supplied from the manifold via the interconnector. The solid oxide fuel cell is supplied with a predetermined voltage level by supplying a fuel gas and an oxidant gas to each single cell and constructing an electric circuit of the battery having the upper and lower interconnectors as terminals. Can be generated.

  In such a solid oxide fuel cell, a general interconnector is used to collect fuel gas evenly to the reaction interface of the cell without depending on a subtle difference in the shape of the cell generated in the manufacturing process. A plurality of grooves and columnar protrusions are formed on a surface that contacts the electric member (hereinafter referred to as “contact surface”) (see, for example, Patent Document 1). The fuel gas guided to the contact surface spreads uniformly in the contact surface by flowing between the interconnector and the current collecting member along the arrangement of the grooves and protrusions. After spreading uniformly in this way, the fuel gas and the oxidant gas pass through the current collecting member and reach the single cell. As a result, the fuel gas and the oxidant gas are uniformly supplied to the fuel electrode or air electrode of the single cell.

  The grooves and protrusions on the contact surface are formed by cutting or etching a metal flat plate (see, for example, Non-Patent Document 1). However, in order to achieve cost reduction, it is desirable to use a metal plate that is thinner than the interconnector, or to perform a pressing process, a punching process, or the like rather than a cutting process or an etching process. .

JP 2008-117737 A

Magnes Co., Ltd., Business Guide, Fuel Cell Related Parts, [on line], Search January 30, 2012, Internet <URL: http://magnex.co.jp/products/>

  However, in order to form grooves and protrusions in the interconnector, it is necessary to use a plate having a certain thickness, and complicated precision processing must be performed. It has been difficult to achieve a reduction in cost by a method of uniformly supplying the.

  Then, an object of this invention is to provide the manufacturing method of the solid oxide fuel cell which can implement | achieve cost reduction.

  In order to solve the above-described problems, a method for manufacturing a solid oxide fuel cell according to the present invention includes a flat fuel electrode, an electrolyte composed of a solid oxide disposed on the fuel electrode, and an electrolyte on the electrolyte. A flat cell electrode-supported single cell comprising an air electrode disposed on the surface and a recess for accommodating the single cell, the bottom surface of the recess being disposed opposite the fuel electrode, and supplying fuel gas to the fuel electrode A first interconnector, a second interconnector disposed opposite to the air electrode and supplying an oxidant gas to the air electrode, and a current collecting member disposed between the fuel electrode and the first interconnector A method of manufacturing a solid oxide fuel cell comprising: a first cell interconnect and a second interconnector, wherein the first interconnector and the second interconnector The concave bottom surface and the second in the combined state A current collecting member having a thickness larger than the value obtained by subtracting the thickness of the single cell from the distance from the interconnector is disposed on the recessed portion, and the current collecting member disposed on the recessed portion is disposed on the current collecting member accommodated in the recessed portion. And a combination step of combining the first interconnector and the second interconnector by disposing the cell and pressing the second interconnector toward the first interconnector. .

  In the method for manufacturing a solid oxide fuel cell, the current collecting member may be made of a foam metal having a porosity of 95% to 98%.

  In the method for manufacturing a solid oxide fuel cell, the current collecting member may be made of any one of nickel alloy, nickel, and stainless steel.

  The solid oxide fuel cell manufacturing method may further include a metal grid disposed between the first interconnector and the current collecting member.

  According to the present invention, the bottom surface of the recess and the second interconnect in a state where the size of the warp in the normal direction of the single cell is three times or more and the first interconnector and the second interconnector are combined. By using a current collecting member having a thickness larger than the value obtained by subtracting the thickness of the single cell from the distance from the connector, the fuel gas can be uniformly supplied to the single cell without providing grooves or protrusions. Therefore, cost reduction can be realized.

FIG. 1 is a cross-sectional view showing the configuration of a cell of a solid oxide fuel cell according to an embodiment of the present invention. FIG. 2 is a diagram showing the relationship between the flow rate of the fuel gas and the cell voltage when constant current power generation is performed in the embodiment of the present invention and the conventional cell. FIG. 3 is a diagram showing the relationship between the flow rate of the fuel gas and the cell voltage when performing constant current power generation using current collecting members having different thicknesses. FIG. 4 is a diagram showing a difference in cell voltage when b / a is changed from 1.3 to 4.7. FIG. 5 is a diagram showing a simulation result of a two-dimensional flow velocity distribution in the fuel electrode side interconnector in the embodiment of the present invention. FIG. 6 is a cross-sectional view showing a configuration in which a metal grid is provided in a cell of a solid oxide fuel cell according to an embodiment of the present invention.

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

<Configuration of solid oxide fuel cell>
As shown in FIG. 1, the solid oxide fuel cell according to the present embodiment includes a single cell 11 and a recess 121 that accommodates the single cell 11 at the center of the upper surface. A flat electrode electrode interconnector 12 which is disposed opposite to the fuel electrode of the cell 11 and supplies fuel gas to the fuel electrode and is electrically connected to the fuel electrode; and an air electrode of the single cell 11; A flat air electrode interconnector 13 is provided which supplies an oxidant gas to the air electrode and is electrically connected to the air electrode. Such a cell 1 functions as a part of a solid oxide fuel cell stack in which a plurality of the cells 1 are stacked in order to obtain a practical output.

  The cell 1 includes a current collecting member 14 disposed between the single cell 11 and the recess 121 of the fuel electrode interconnector 12, an insulating member 15 disposed on the upper surface of the fuel electrode interconnector 12, The electrolyte of the single cell 11 and the metal foil 16 disposed on the upper surface of the insulating member 15 are provided.

The unit cell 11 has a fuel electrode support type structure composed of a flat fuel electrode, an electrolyte formed on the upper surface of the fuel electrode, and an air electrode formed on the upper surface of the electrolyte. Such a single cell 11 as a whole has a planar shape equivalent to the recess 121 of the fuel electrode interconnector 12.
Here, the fuel electrode is made of, for example, a metal Ni and an electrolyte such as nickel-added yttria stabilized zirconia (Ni-YSZ), nickel-added samaria stabilized zirconia (Ni-SSZ), and nickel-added scandia stabilized zirconia (Ni-ScSZ). It is comprised from the mixture with the material which comprises.
The electrolyte includes, for example, scandia-stabilized zirconia (ScSZ), yttria-stabilized zirconia (YSZ), samaria-stabilized zirconia (SSZ), cobalt-added lanthanum gallate oxide (LSGMC), and the like.
Examples of the air electrode include lanthanum nickel ferrite (LNF), lanthanum manganate (LSM), lanthanum strontium cobaltite (LSC), lanthanum strontium cobaltite ferrite (LSCF), lanthanum strontium ferrite (LSF), samarium strontium cobaltite (SSC). ) Etc.

  The fuel electrode interconnector 12 has a plate shape, and is formed with a recess 121 formed at the center of the upper surface. In addition, a fuel supply port 122 that supplies fuel gas supplied from the outside toward the current collecting member 14 is formed at the center of the bottom surface of the recess 121. Further, a fuel discharge port 123 for discharging unreacted fuel gas to the outside is formed at the outer edge of the bottom surface of the recess 121. Such a fuel electrode interconnector 2 is made of, for example, a ferritic heat-resistant alloy containing about 16 to 25% of chromium.

  The air electrode interconnector 13 has a plate shape, and an oxidant supply port 131 that supplies an oxidant gas such as air supplied from the outside toward the metal foil 16 is formed at the center of the lower surface. Such an air electrode interconnector 132 is made of, for example, a ferritic heat-resistant alloy containing about 16 to 25% of chromium.

  The current collecting member 14 has a plate shape having a planar shape equivalent to the outer shape of the recess 121. The current collecting member 14 is made of any one of nickel alloy, nickel, and stainless steel.

  The insulating member 15 has an outer shape equivalent to that of the fuel electrode interconnector 12, and an opening equivalent to the concave portion 121 is formed at the center thereof, and is disposed on the upper surface around the concave portion 121 of the fuel electrode interconnector 12. . Such an insulating member 15 is made of, for example, ceramics that are insulative at high temperatures such as alumina, or insulating materials such as mica. By providing such an insulating member 15, a short circuit between the fuel electrode interconnector 12 and the air electrode interconnector 13 can be prevented.

  The metal foil 16 has an outer shape equivalent to that of the fuel electrode interconnector 12, and an opening equivalent to the air electrode of the single cell 11 is formed at the center thereof, the outer edge being the insulating member 15, and the inner edge being the single edge. It is joined to the electrolyte of the cell 11. Thereby, the fuel electrode side and the air electrode side of the single cell 11 are hermetically separated. Such a metal foil 16 is made of a metal such as aluminum SUS, for example.

<Assembly method of solid oxide fuel cell>
An example of a method for assembling the solid oxide fuel cell will be described.

  First, the fuel electrode interconnector 12 in which the recess 121, the fuel supply port 122, and the fuel discharge port 123 are formed is disposed on a base made of a heat-resistant alloy. The current collecting member 14 is placed on the bottom surface of the recess 121 of the fuel electrode interconnector 2. The thickness of the current collecting member 14 at this time is at least three times the warpage of the single cell 11, and the bottom surface of the recess 121 and the air electrode in a state where the fuel electrode interconnector 12 and the air electrode interconnector 13 are combined. It is formed larger than the value obtained by subtracting the thickness of the single cell 11 from the distance from the lower surface of the interconnector 13. The current collecting member 14 preferably has a porosity of 95% or more and 98% or less, and is made of a foam metal having a pore size of 600 μm or less. The reason why the current collecting member 14 is configured as described above will be described later.

  When the current collecting member 14 is disposed inside the recess 121, the single cell 11 is placed on the current collecting member 14 so that the fuel electrode is positioned on the current collecting member 14.

  When the single cell 11 is disposed on the current collecting member 14 accommodated in the recess 121, the upper surface of the fuel electrode interconnector 12 is obtained in order to obtain electrical insulation between the fuel electrode interconnector 12 and the air electrode interconnector 13. That is, the insulating member 15 is disposed on the edge of the upper surface of the fuel electrode interconnector 12 excluding the opening of the recess 121.

  When the insulating member 15 is disposed, the metal foil 16 is disposed from the upper surface of the electrolyte of the single cell 11 to the upper surface of the insulating member 15.

  When the metal foil 16 is disposed, the air electrode interconnector 13 in which the oxidant supply port 131 is formed is prepared, and the air electrode interconnector 13 is disposed on the metal foil 16.

  When the air electrode interconnector 13 is disposed, a load is applied from the air electrode interconnector 13 toward the fuel electrode interconnector 12, and the fuel electrode interconnector 12 and the air electrode interconnector 13 are combined. Thereby, since the current collection member 14 is press-contacted with the fuel electrode interconnector 12, the electrical connection of the fuel electrode interconnector 12 and the current collection member 14 becomes favorable. In addition, since the air electrode interconnector 13 is pressed against the air electrode of the single cell 11, electrical insulation between the air electrode interconnector 13 and the air electrode is improved.

  When the fuel electrode interconnector 12 and the air electrode interconnector 13 are combined and then heated to a power generation state, for example, the single cell 11 is connected to the fuel electrode interconnector 12 and the air electrode interconnector 13 via the current collecting member 14. A solid oxide fuel cell consisting of one cell 1 held in between is completed.

  In a stack in which a plurality of such cells 1 are stacked, the fuel electrode interconnector 12 and the air electrode interconnector 13 are electrically connected to the fuel electrode interconnector 12 or the air electrode interconnector 13 of the cells adjacent vertically. It is connected. Therefore, electric power can be taken out by connecting the air electrode interconnector 13 at the upper end and the fuel electrode interconnector 12 at the lower end of the solid oxide fuel cell stack to the load circuit as terminals.

<Power generation operation of solid oxide fuel cell>
Next, the power generation operation of the solid oxide fuel cell assembled by the procedure as described above is performed by the procedure shown below.

  First, fuel gas such as dry hydrogen is supplied from the fuel supply port 122 of the fuel electrode interconnector 12 to the fuel electrode of the single cell 11 via the current collecting member 14. On the other hand, an oxidant gas such as air is supplied from the oxidant supply port 131 of the air electrode interconnector 13 to the air electrode of the single cell 11. As described above, when the fuel gas and the oxidant gas are supplied to the single cell 11 at a predetermined temperature, an electrochemical reaction occurs between the fuel electrode and the air electrode. In this state, when the air electrode interconnector 13 at the upper end and the fuel electrode interconnector 12 at the lower end of the solid oxide fuel cell stack are connected to the load circuit as terminals, electric power can be taken out.

<Configuration of current collecting member>
Next, the configuration of the current collecting member 14 before assembly will be described.
As shown in FIG. 1, the cell according to the present embodiment secures a space for accommodating the single cell 11 with the fuel electrode interconnector 12 and the air electrode interconnector 13 against the load from the air electrode interconnector 13 side. In addition, by applying an appropriate load to the single cell 11 and the current collecting member 14 using the load, the electric resistance between the fuel electrode of the single cell 11 and the current collecting member 14 is reduced. Yes. In the cell 1 having such a configuration, the current collecting member 14 is set as follows.

  First, the thickness of the current collecting member 14 is set so as to satisfy the following expression (1). Thereby, the gas diffusibility equivalent to the case where the interconnector which formed the protrusion by the conventional expensive process is used can be obtained. In the following formula (1), “a” indicates the amount of warpage of the single cell 11, and “b” indicates the thickness of the current collecting member 14. The warpage of the single cell 11 indicates the amount of deformation of the flat single cell 11 in the normal direction.

b ≧ 3a (1)

  FIG. 2 shows the relationship between the flow rate of the fuel gas and the cell voltage when constant current power generation is performed in the cell 1 shown in FIG. In FIG. 2, the measured value in the cell 1 according to the present embodiment indicated by the black triangle mark is the ratio of the thickness of the current collecting member 14 before stacking to the magnitude of warpage of the single cell 11, that is, b / a is 4.7. For reference, the measured values (black diamonds in FIG. 2) when using an interconnector in which protrusions and grooves are formed by expensive processing without using the current collecting member 14 made of foam metal are also shown in FIG. Show.

  In general, it can be said that a cell having a smaller voltage drop even when the flow rate of the fuel gas is decreased is a cell with good fuel diffusion. As shown in FIG. 2, in the cell 1 according to the present embodiment, the voltage drop when the fuel gas flow rate is reduced is substantially equal to the case where an interconnector having protrusions or the like formed by expensive processing is used. I understand. From this, it can be seen that by controlling the thickness of the current collecting member 14, the fuel gas can be supplied uniformly as in the case where the protrusions are formed on the interconnector.

  Therefore, in order to determine the thickness of the current collecting member 14, the fuel gas flow rate and the cell voltage when the constant current power generation is performed by the cell using the current collecting member 14 having two different thicknesses. The relationship was measured. The measurement results are shown in FIG.

  As shown in FIG. 3, when b / a is 1.3 (black square mark in FIG. 3), the voltage drops greatly when the fuel gas flow rate is decreased. It shows that there is. On the other hand, when b / a is 4.7 (black triangle mark in FIG. 3), the voltage drop when the fuel gas flow rate is decreased is the same as the case of using an interconnector in which protrusions are formed as in the conventional case. Similarly, since there are few, it turns out that a problem is not seen by the diffusibility of gas.

  As apparent from FIG. 3, when the fuel gas flow rate is large, the influence of b / a on the cell voltage is small, and as the fuel gas flow rate decreases, the value of the cell using the current collecting member having a small b / a value is reduced. The voltage drops rapidly. Therefore, it is considered how the difference between the cell voltage when the fuel gas flow rate is 467 ml / min and the cell voltage when the fuel gas flow rate is 438 ml / min changes when the current collecting member 14 having different b / a is used. did. FIG. 4 shows the difference in cell voltage when b / a is changed from 1.3 to 4.7.

  As shown in FIG. 4, when b / a is smaller than 3, the difference in cell voltage is large, and the cell voltage rapidly decreases as the fuel gas flow rate decreases, whereas b / a is larger than 3. In this case, the difference in cell voltage is small, and it can be seen that sufficient fuel gas is supplied to the entire fuel electrode even if the fuel gas flow rate is reduced. If the value of b / a is smaller than 3 as described above, the reason why the cell voltage suddenly decreases as the fuel gas flow rate decreases is as follows. As shown in FIG. It is mentioned that the current collecting member 14 in contact with the cell is strongly compressed as compared with the cell central portion. If b / a is larger than 3, the region of the current collecting member 14 remains between the fuel electrode interconnector 12 and the single cell 11 in the outer peripheral portion of the cell, but if b / a is smaller than 3, the single cell 11, the thickness of the current collecting member 14 in the vicinity of the outer peripheral portion, in other words, the thickness of the gas flow path is thin, and the pores in the current collecting member 14 are crushed by compression, so that a sufficient gas flow path is provided. It cannot be secured. On the other hand, when b / a is larger than 3, although a part of the pores inside the current collecting member 14 is crushed near the outer periphery of the single cell 11, a sufficient pore diameter is maintained even after pressurization. It is considered that a sufficient gas flow path is ensured because the pores that remain are left with a certain thickness. Therefore, in the present embodiment, the thickness of the current collecting member 14 is set so as to satisfy the above formula (1).

  Further, the thickness of the current collecting member 14 accommodates the cells formed in these interconnectors when the fuel electrode interconnector 12 and the air electrode interconnector 13 are combined to assemble the fuel cell stack. It is set to be larger than the value obtained by subtracting the thickness of the single cell 1 from the depth of the space (hereinafter referred to as “storage portion”). The reason is as follows.

  The depth d of the storage part in FIG. 1 is obtained by adding the thickness of the insulating member 15 and the metal foil 16 to the depth of the recess 121 of the fuel electrode interconnector 12. If the thickness of the current collecting member 14 is smaller than the depth of the storage portion, the force for pressing the air electrode interconnector 13 against the single cell 11 is not sufficiently generated when the cell is assembled as shown in FIG. The surface of the current collecting member 14 on the side in contact with the single cell 11 cannot be deformed according to the shape of the single cell 11 so that the two can be brought into close contact with each other. In such a state, the electrical conductivity between the fuel electrode and the current collecting member 14 is low, and a large loss occurs in the power generation output as the fuel cell. In FIG. 1, the air electrode interconnector 13 is formed in a flat plate shape. However, when the air electrode interconnector 13 is provided with a recess for housing the single cell 11 and the current collecting member 14. The depth of the recess provided in the air electrode interconnector 13 is also added to the depth d of the storage portion. Further, when a gas seal material or the like is disposed between the two interconnectors, the thickness of these members is also added to the depth d of the storage portion.

  On the other hand, if the current collecting member 14 is too thick, a very large force is required to significantly compress the current collecting member 14 in order to house the current collecting member 14 and the single cell 1 in the housing portion. . For this reason, when the stack is pressurized from above at normal pressure when assembling the fuel cell stack, the current collector 14 is not compressed to a size that can be accommodated in the accommodating portion, and the fuel electrode interconnector 12 and the air electrode interconnector are not compressed. An air gap is generated between the two. In such a state, the pores of the entire current collecting member 14 are crushed by compression, so that sufficient air permeability cannot be ensured, and cracking occurs in the single cell 11 due to excessive pressure, or the air electrode interconnector. 13 is highly likely to be deformed, and the cell 1 may be damaged. Therefore, in order to examine an appropriate thickness of the current collecting member 14, the depth of the storage portion was changed using a single cell having a diameter of 120 mm and a current collecting member having a thickness of 1.4 mm before assembly. Experiments were conducted on the power generation characteristics and damage situation of the cell. As a result, it was confirmed that particularly good power generation characteristics can be obtained when the depth is about 3.5% to 6.9% larger than the depth d of the storage portion.

  Further, as the foam metal used for the current collecting member 14, a metal having a porosity of 95% or more and 98% or less and a pore diameter of 600 μm or less before assembly is desirable. The reason is as follows.

  FIG. 5 shows a two-dimensional flow velocity distribution in the fuel electrode side interconnector 12 when a foam metal having a porosity of 95% and a pore diameter of 600 μm is used as the current collecting member 14 in the cell 1 having a b / a value of 3 or more. This is a simulation result. In FIG. 5, the flow velocity distribution of the porous portion of the current collecting member 14 was calculated by approximating the viscosity from the differential pressure during ventilation. In FIG. 5, the circular portion described in the central portion is a fuel supply port 122 into which 467 ml of hydrogen flows per minute, and the rectangular portions described in two locations at both ends are fuel discharge ports 123 opened to atmospheric pressure. .

  As is apparent from FIG. 5, when a foam metal having a porosity of 95% and a pore diameter of 600 μm is used for the current collecting member 14, even when the fuel supply port 122 and the fuel discharge port 123 are smaller than the area of the fuel electrode. It can be seen that a radial flow velocity of 1 [mm / sec] or more can be obtained over almost the entire surface. Accordingly, by using the foam metal as the current collecting member 14 and using a structure that can ensure the air permeability of the current collecting member 14 even after assembly pressurization with b ≧ 3a, grooves and protrusions due to expensive processing become unnecessary. The processing cost of the cell 1 can be reduced. At this time, if the porosity is remarkably smaller than 95% or the pore diameter is remarkably smaller than 600 μm, the flow path through which the fuel gas passes is likely to be blocked or a gas leak may occur due to the high pressure applied to the upstream of the flow path. Become. Further, if the porosity is significantly larger than 95% or the pore diameter is significantly larger than 600 μm, the gas does not diffuse near the outer edge having no fuel discharge port 123. Therefore, it is desirable that the porosity of the foamed member is 95% or more and 98% or less, and the pore diameter is 600 μm.

  As described above, according to the present embodiment, the recess 121 is at least three times the warpage of the single cell 11 and the fuel electrode interconnector 12 and the air electrode interconnector 13 are combined. By using the current collecting member 14 having a thickness larger than the value obtained by subtracting the thickness of the single cell 11 from the distance between the bottom surface and the air electrode interconnector 13, there is no provision of grooves or protrusions in the interconnector as in the prior art. However, since the fuel gas can be uniformly supplied to the single cell 11, the manufacturing cost of the interconnector can be greatly reduced, and as a result, the cost can be reduced. Moreover, since the tolerance limit regarding the curvature at the time of manufacture of the single cell 11 is eased, the manufacture of the single cell 11 is facilitated, and as a result, the manufacturing cost of the single cell 11 can be reduced.

  Note that, as in the cell 2 shown in FIG. 6, a metal grid 21 made of nickel or the like may be provided between the fuel electrode separator 12 and the current collecting member 14. Such a metal grid 12 is disposed by placing it on the bottom surface of the recess 121 before disposing the current collecting member 14 inside the recess 121.

  By providing the metal grid 21, the pores of the current collecting member 14 gradually collapse with the passage of time in the region due to the stress concentration in the outer peripheral region of the opening such as the fuel supply port 122, and the air permeability of the current collecting member 14 Can be prevented from decreasing. Thereby, the stable supply path | route of fuel gas can be ensured also in long-term power generation. In the case of the cell 2 in FIG. 6, the depth d of the storage portion of the cell 2 is the distance from the surface where the metal grid 12 and the current collecting member 14 are in contact to the surface where the air electrode interconnector 14 and the single cell 11 are in contact. is there.

  The present invention can be applied to a solid oxide fuel cell having a fuel cell-supported single cell.

  DESCRIPTION OF SYMBOLS 1, 2 ... Cell, 11 ... Single cell, 12 ... Fuel electrode interconnector, 13 ... Air electrode interconnector, 14 ... Current collecting member, 15 ... Insulating member, 16 ... Metal foil, 21 ... Metal lattice, 121 ... Recessed part, 122 ... Fuel supply port, 123 ... Fuel discharge port, 131 ... Oxidant supply port.

Claims (4)

A flat cell electrode-supported single cell consisting of a flat fuel electrode, an electrolyte made of a solid oxide disposed on the fuel electrode, and an air electrode disposed on the electrolyte, and the single cell are accommodated A first interconnector for supplying a fuel gas to the fuel electrode; a first interconnector for supplying fuel gas to the fuel electrode; and an oxidant gas for the air electrode. A method for producing a solid oxide fuel cell comprising: a second interconnector to be supplied; and a current collecting member disposed between the fuel electrode and the first interconnector,
The bottom surface of the recess and the second interconnector in a state in which the size of the warp in the normal direction of the single cell is three times or more and the first interconnector and the second interconnector are combined. A current collecting member disposing step of disposing the current collecting member having a thickness larger than a value obtained by subtracting the thickness of the single cell from the distance to the concave portion;
The single cell is disposed on the current collecting member accommodated in the concave portion, and the second interconnector is pressed toward the first interconnector to press the first interconnector and the second interconnector. A combination step of combining with a connector; and a method of manufacturing a solid oxide fuel cell. The method for producing a solid oxide fuel cell according to claim 1, wherein the current collecting member is made of a foam metal having a porosity of 95% to 98%. The method for producing a solid oxide fuel cell according to claim 1, wherein the current collecting member is made of any one of nickel alloy, nickel, and stainless steel. Before the current collecting member disposing step, further comprising a metal lattice disposing step of disposing a metal lattice in the recess,
4. The solid oxide according to claim 1, wherein, in the current collecting member disposing step, the current collecting member is disposed on the metal grid disposed in the concave portion. 5. Of manufacturing a fuel cell.