JP2018195496A - Power collection structure for fuel battery cell, and manufacturing method thereof - Google Patents

Abstract

To improve conductivity between a fuel battery cell and a cap.SOLUTION: A conductive cap is fitted to an end of a fuel battery cell. The cap is fitted in such a manner that an inner surface of a bottom part and an inner peripheral surface of a cylindrical part enclose an end face of the end and an outer peripheral surface of the fuel battery cell. A film-like first conductive layer is provided on an outer peripheral surface and an end face in an end of an inner electrode layer. Between an inner surface of the bottom of the cap/the inner peripheral surface of the cylindrical part and the first conductive layer, a second conductive layer is provided for electrically connecting both the inner surface/the inner peripheral surface and the first conductive layer. The film-like first conductive layer is provided in the inner electrode layer, thereby securing a sufficient electrical contact area between the first conductive layer and the inner electrode layer. Further, even if air is residual or a sink occurs in the second conductive layer, conductivity of the first conductive layer and the second conductive layer is prevented from being considerably impaired. Thus, the inner electrode layer and the cap can be electrically excellently connected via the first conductive layer and the second conductive layer.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a current collecting structure for a fuel cell and a method for manufacturing the same.

  Conventionally, a current collecting structure of this type of fuel cell includes a cylindrical inner electrode layer, a cylindrical outer electrode layer, and an electrolyte layer disposed between the inner electrode layer and the outer electrode layer. A cylindrical fuel cell has been proposed in which an inner electrode terminal (cap) for current collection is attached to an end of the fuel cell (for example, see Patent Document 1). The inner electrode layer is provided with an exposed portion that is not covered with the electrolyte layer and the outer electrode layer at the end thereof. The cap is formed in a cup shape (bottomed cylindrical member) and filled with a silver seal material between the inner peripheral surface of the cylindrical portion of the cup and the inner surface of the bottom portion, and the outer peripheral surface and end surface of the exposed portion of the inner electrode layer. Has been.

Republished patent WO2013 / 047667A1

  In the fuel cell current collection structure described above, since the clearance between the inner electrode layer and the cap is small, air tends to remain between the inner electrode layer and the cap even if an attempt is made to fill the silver sealing material. Further, when a paste is used as the silver sealing material, volume shrinkage may occur in the firing process, and sink marks (concave marks) may be generated. If such air or sink marks occur between the inner electrode layer and the cap, the contact area between the inner electrode layer and the sealing material is reduced, the electrical resistance between the inner electrode layer and the cap increases, and the cell performance decreases. Will be invited.

  The main object of the present invention is to provide a current collecting structure with good conductivity between a fuel cell and a cap.

  The present invention adopts the following means in order to achieve the main object described above.

  The present invention relates to a current collector for a cylindrical fuel cell having a cylindrical inner electrode layer, a cylindrical outer electrode layer, and an electrolyte layer disposed between the inner electrode layer and the outer electrode layer. A conductive cap fitted to an end of the fuel cell and electrically connected to the inner electrode layer, the cap from an annular bottom and an outer peripheral side of the bottom A cylindrical portion extending in a cylindrical shape, and the inner surface of the bottom portion and the inner peripheral surface of the cylindrical portion are fitted so as to surround the end surface and the outer peripheral surface of the end portion of the fuel cell, respectively, A film-like first conductive layer is provided on the outer peripheral surface and the end surface of the end portion of the inner electrode layer, and both are provided between the inner surface of the bottom portion and the inner peripheral surface of the cylindrical portion, and the first conductive layer. The gist is that a second conductive layer to be electrically joined is provided.

  In the fuel cell collecting structure of the present invention, the cap is fitted so that the inner surface of the bottom and the inner peripheral surface of the cylindrical portion surround the end surface and outer peripheral surface of the end of the fuel cell, respectively. A film-like first conductive layer is provided on the outer peripheral surface and the end surface of the end portion of the inner electrode layer, and between the inner surface of the bottom of the cap and the inner peripheral surface of the cylindrical portion and the first conductive layer, both A second conductive layer is provided to electrically join the two. By providing the film-shaped first conductive layer on the inner electrode layer, a sufficient electrical contact area between the first conductive layer and the inner electrode layer can be ensured. Further, even if air remains or sinks in the second conductive layer, the conductivity between the first conductive layer and the second conductive layer is not significantly impaired. For this reason, since the inner electrode layer and the cap can be electrically connected to each other through the first conductive layer and the second conductive layer, the conductivity between the fuel cell and the cap is good. It can be.

  In the current collecting structure for a fuel cell according to the present invention, the first conductive layer may be provided on an inner peripheral surface of the inner electrode layer. By doing so, the electrical contact area between the first conductive layer and the inner electrode layer can be further secured, so that the conductivity between the fuel cell and the cap can be made better. .

  In the current collecting structure for a fuel cell according to the present invention, the first conductive layer and the second conductive layer may be formed of the same material. By so doing, the thermal stress can be reduced by eliminating the difference in thermal expansion between the first conductive layer and the second conductive layer with respect to temperature changes, so that the electrical connection between the two can be maintained well.

  A method for producing a current collecting structure for a fuel cell according to the present invention includes a cylindrical inner electrode layer, a cylindrical outer electrode layer, and an electrolyte layer disposed between the inner electrode layer and the outer electrode layer. A method of manufacturing a current collecting structure of a cylindrical fuel cell having a step of applying a conductive paste to at least an outer peripheral surface and an end surface at an end of the inner electrode layer, and applying to the inner electrode layer A cap having a step of solidifying the conductive paste to form a film-shaped first conductive layer, an annular bottom portion, and a cylindrical portion extending in a cylindrical shape from the outer peripheral side of the bottom portion, an inner surface of the bottom portion And a step of fitting the inner peripheral surface of the cylindrical portion so as to surround an end surface and an outer peripheral surface of the end portion of the inner electrode layer, respectively, an inner surface of the bottom portion of the cap and an inner peripheral surface of the cylindrical portion; In a state where a conductive paste is filled between the first conductive layer and Forming a second conductive layer by solidifying the conductive paste is summarized in that including.

  In the manufacturing method of a current collecting structure for a fuel cell according to the present invention, a conductive paste is applied to at least the outer peripheral surface and the end surface at the end portion of the inner electrode layer, and the conductive paste is solidified to form a first conductive film. Form a layer. Then, a cap is fitted so as to surround the end surface and the outer peripheral surface of the end portion of the inner electrode layer, and the conductive paste is interposed between the inner surface of the bottom portion of the cap and the inner peripheral surface of the cylindrical portion, and the first conductive layer. In the filled state, the conductive paste is solidified to form a second conductive layer. Accordingly, the second conductive layer can be formed after the film-like first conductive layer is reliably formed on the inner electrode layer. For this reason, a sufficient electrical contact area between the first conductive layer and the inner electrode layer can be ensured. In addition, even when air remains or sinks when the conductive paste that becomes the second conductive layer is solidified, the conductivity between the first conductive layer and the second conductive layer is not significantly impaired. For this reason, since the inner electrode layer and the cap can be electrically connected to each other through the first conductive layer and the second conductive layer, the conductivity between the fuel cell and the cap is good. It can be.

It is a block diagram which shows the outline of a structure of the electric power generation module 10 which has the fuel cell 40 of this embodiment. It is sectional drawing which expands and shows the cross section of the circular part of the dashed-two dotted line in the electric power generation module 10 of FIG. It is explanatory drawing which shows a cap assembly | attachment process. It is explanatory drawing which shows the mode of a cap assembly | attachment. It is sectional drawing of the edge part 140a of the fuel cell 140 of other embodiment.

  Next, modes for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a power generation module 10 having a fuel cell 40 of the present embodiment, and FIG. It is sectional drawing. As shown in FIG. 1, the power generation module 10 includes a vaporizer 22 that generates water vapor, and a fuel gas (reformed gas) containing hydrogen by reforming raw fuel gas such as natural gas or LP gas through a steam reforming reaction. ), A fuel cell stack 30 in which a plurality of fuel cells 40 that generate power by reacting a fuel gas containing hydrogen and an oxidant gas containing oxygen are stacked, and a fuel gas supply pipe 26 The fuel gas manifold 34 is connected to the reformer 24 through the fuel cell and distributes the fuel gas from the reformer 24 to each fuel cell 40, and the oxidant gas manifold 38 distributes the oxidant gas to each fuel cell 40. These are housed in the module case 11. The power generation module 10 constitutes a fuel cell system by being combined with a hot water supply unit (hot water storage tank) (not shown) that recovers and supplies hot water generated by the power generation.

  The module case 11 is formed in a box shape from a heat insulating material, and the raw fuel gas supply pipe 12, the reformed water supply pipe 14, and the air supply pipe 16 are connected. The raw fuel gas supply pipe 12 is a pipe for supplying the raw fuel gas from a supply source to the vaporizer 22, and the pipe is provided with an on-off valve, a pump, a flow meter, a pressure gauge, a desulfurizer, and the like. The reforming water supply pipe 14 is a pipe that supplies the reforming water to the vaporizer 22, and the pipe is provided with a reforming water tank, a pump, and the like. The air supply pipe 16 is a pipe that supplies air as an oxidant gas to the oxidant gas manifold 38, and an air blower, a flow meter, and the like are provided in the pipe.

  Further, the module case 11 is provided with a combustion section 28 for supplying heat necessary for the generation of water vapor by the vaporizer 22 and the steam reforming reaction by the reformer 24. The combustion unit 28 ignites and burns surplus fuel gas (anode offgas) and oxidant gas (cathode offgas) that have not been used for the power generation reaction of the fuel battery cell 40, thereby using the combustion heat to vaporize the carburetor 22. And the reformer 24 is heated. The combustion exhaust gas generated by the combustion of the combustion unit 28 is discharged out of the case through the combustion exhaust gas exhaust pipe 18 provided in the upper part of the module case 11. Note that a heat exchanger (not shown) is connected to the combustion exhaust gas discharge pipe 18, and the heat exchanger warms the hot water supplied from the hot water storage tank through the circulation pipe by heat exchange with the combustion exhaust gas. The combustion exhaust gas that has passed through the heat exchanger is condensed by heat exchange with the hot water, and the condensed water is collected in the reformed water tank.

  As shown in FIG. 2, the fuel cell 40 includes a cylindrical electrolyte layer 42 having a dense structure made of an oxygen ion conductor, and a fuel electrode layer having a porous structure as an anode laminated inside the electrolyte layer 42 ( A cylindrical solid oxide fuel cell (inner electrode layer) 44 and a porous oxidant electrode layer (outer electrode layer) 46 as a cathode laminated on the outside of the electrolyte layer 42. The cell is configured as a cell (SOFC) cell, and a current collecting cap 50 is attached to both ends in the longitudinal direction so as to be electrically connected to the fuel electrode layer 44. A fuel gas flow path 44a through which fuel gas flows is formed inside the fuel electrode layer 44. In the fuel cell 40, the fuel gas flow path 44a and the fuel gas manifold 34 communicate with each other as shown in FIG. In this manner, the fuel gas manifold 34 is erected on the support plate 36. As shown in FIG. 2, the fuel electrode layer 44 is provided with an exposed portion 44 b that is not covered with the electrolyte layer 42 and the oxidant electrode layer 46 at the end.

  The electrolyte layer 42 is, for example, one or more selected from stabilized zirconia doped with one or more selected from rare earth elements such as Y, Sc and Ce, and rare earth elements such as Gd, Y and Sm. Can be used, such as ceria doped with lanthanum gallate doped with one or more selected from Ni, Sr, Mg, Co, Fe, Cu.

  The fuel electrode layer 44 is made of, for example, a mixture of a catalytic metal such as Ni or Fe and a stabilized zirconia doped with one or more selected from rare earth elements such as Y, Sc, and Ce, and Ni and Fe. A mixture of a catalyst metal and a ceria doped with one or more rare earth elements such as Gd, Y, Sm, etc., a catalyst metal such as Ni or Fe, and Sr, Mg, Co, Fe, Cu A mixture with lanthanum gallate doped with one or more kinds can be used.

  The oxidant electrode layer 46 includes, for example, lanthanum manganite doped with one or two selected from Sr and Ca, lanthanum ferrite doped with one or more selected from Sr, Co, Ni, and Cu, Sr , Lanthanum cobaltite doped with one or more selected from Fe, Ni, Cu, barium cobaltite doped with one or two selected from Sr, Fe, silver, silver-palladium alloy, platinum, etc. Can be used.

  Between the electrolyte layer 42 and the oxidant electrode layer 46, ceria doped with rare earth such as ceria doped with gadolinium (GDC), ceria doped with yttria (YDC), ceria doped with samarium (SDC), or the like. It is also preferable to provide a reaction preventing layer using a mixture.

  The cap 50 is formed of, for example, a metal material such as ferritic stainless steel. As shown in FIG. 2, the cap 50 has an annular bottom portion 52, a cylindrical portion 54 that extends in a cylindrical shape from the outer peripheral side of the bottom portion 52, and the bottom portion 52. A projection 56 extends in a cylindrical shape in the opposite direction to the cylindrical portion 54 from the inner peripheral side. The cap 50 is fitted to the fuel cell 40 so that the inner surface of the bottom portion 52 and the inner peripheral surface of the cylindrical portion 54 surround the end surface and the outer peripheral surface of the end portion 40a of the fuel cell 40, respectively. A current collecting layer 62 formed in a film shape on the outer peripheral surface and the end surface is provided at the end 40 a of the fuel cell 40 (the exposed portion 44 b of the fuel electrode layer 44). A conductive bonding layer 64 that is electrically bonded to the current collecting layer 62 is provided between the current collecting layer 62 and the upper surface of the bottom portion 52 of the cap 50 and the inner peripheral surface of the cylindrical portion 54. Thus, the current collecting layer 62 and the conductive bonding layer 64 provide a gap between the upper surface of the bottom 52 of the cap 50 and the inner peripheral surface of the cylindrical portion 54 and the end surface and outer peripheral surface of the end 40a of the fuel cell 40. The fuel gas that is electrically connected and flows through the fuel gas passage 44a inside the fuel electrode layer 44 is sealed so as not to leak to the outside (oxidant electrode layer 46 side). The current collecting layer 62 and the conductive bonding layer 64 are formed using a material having high conductivity such as a conductive paste such as platinum, silver, copper, or a silver-palladium alloy, or a conductive ceramic such as lanthanum chromite. Can do. In the present embodiment, the current collecting layer 62 and the conductive bonding layer 64 are made of the same material. The upper end surface of the conductive bonding layer 64 is covered with a glass seal layer 66. For the glass seal layer 66, for example, crystallized glass excellent in heat resistance and sealability such as alumina-silica crystallized glass can be used. The glass seal layer 66 may not be provided.

  The connection plate 32 is formed of, for example, a metal material such as ferritic stainless steel. As shown in FIG. 1, the cap 50 (the fuel electrode layer 44) of one of the two fuel cells 40 adjacent to each other, as shown in FIG. 1. ) And the oxidant electrode layer 46 of the other fuel cell 40 are electrically connected. The plurality of fuel cells 40 are electrically connected in series by connecting two fuel cells 40 adjacent to each other via the connection plate 32.

  The fuel gas manifold 34 is a box-shaped member having an upper opening, and a support plate 36 is joined so as to close the upper opening and form a sealed space. The support plate 36 has a plurality of through holes 36a formed at predetermined intervals, and a plurality of fuel cells are inserted by inserting the fuel cell 40 so that the protrusions 56 of the cap 50 penetrate the respective through holes 36a. The cell 40 is supported in a standing state. As a result, the fuel gas manifold 34 communicates with the fuel gas flow path 44 a of each fuel cell 40 through the hollow cap 50, and the fuel gas supplied from the fuel gas supply pipe 26 is supplied to the fuel cell 40. Supply (distribution) to the gas flow path 44a. The fuel gas supplied to the fuel gas channel 44a passes through the fuel gas channel 44a and is discharged upward from the upper cap 50. As described above, surplus fuel gas that has passed through the fuel battery cell 40 is combusted in the combustion unit 28 together with the oxidant gas, and is discharged to the combustion exhaust gas exhaust pipe 18 as combustion exhaust gas. The support plate 36 can be formed of, for example, a metal material such as ferritic stainless steel or austenitic stainless steel, or can be formed of an insulating material such as an insulating ceramic. When the support plate 36 is formed of a metal material, an insulating seal member is provided in the through hole 36a in order to electrically insulate the lower cap 50 of the fuel cell 40 and the through hole 36a of the support plate 36. It may be provided.

  A glass seal portion 37 is formed between the fuel cell 40 and the support plate 36, that is, between the outer surface of the bottom portion 52 of the cap 50 and the upper surface of the support plate 36. The glass seal part 37 can be formed using crystallized glass excellent in heat resistance and sealability, such as alumina-silica crystallized glass.

  The oxidant gas manifold 38 is connected to the air supply pipe 16, and a plurality of supply ports 38 a for distributing the oxidant gas (air) to the oxidant electrode layer 46 of each fuel cell 40 are formed. .

  Next, the process for assembling the cap 50 to the fuel cell 40 will be described. FIG. 3 is an explanatory diagram showing the cap assembly process, and FIG. 4 is an explanatory diagram showing how the cap 50 is assembled. Hereinafter, the cap assembly process of FIG. 3 will be described with reference to FIG. In the cap assembling step, first, a conductive paste made of a silver-palladium alloy is applied to the outer peripheral surface and the end surface of the exposed portion 44b of the fuel electrode layer 44 of the fuel battery cell 40 (S100, see FIG. 4A). Then, the applied conductive paste is dried at a predetermined drying temperature (for example, 150 ° C.) to be solidified to form the current collecting layer 62 (S110, see FIG. 4B). Thereby, the film-like current collecting layer 62 having a substantially uniform thickness can be formed on the outer peripheral surface and the end surface of the fuel electrode layer 44. Next, a conductive paste made of a silver-palladium alloy is applied to the inner surface of the bottom portion 52 of the cap 50 and the inner peripheral surface of the outer cylinder portion 54 (S120), and the end portion 40a of the fuel cell 40 is inserted into the cap 50. (S130, see FIG. 4C). Alternatively, the conductive paste may be filled in the gap between the outer cylinder portion 54 of the cap 50 and the fuel cell 40 after the end portion 40 a of the fuel cell 40 is inserted into the cap 50. Further, after the end 40a of the fuel cell 40 is inserted into the cap 50, the gap between the outer cylinder portion 54 of the cap 50 and the fuel cell 40 is filled with glass paste (see FIG. 4C). ).

  Then, the assembly of the fuel battery cell 40 and the cap 50 is placed in a firing furnace, and the interior of the furnace is heated to a predetermined temperature (for example, 850 ° C.), whereby the conductive paste and the glass paste are fired to form a conductive bonding layer. 64 and the glass seal layer 66 are formed (S140, see FIG. 4D), and the assembly of the cap is completed. In the firing in S140, the conductive bonding layer 64 may be formed while air remains in the conductive paste between the outer cylinder portion 54 of the cap 50 and the fuel cell 40. In addition, volume shrinkage of the conductive paste filled in the gap between the outer cylinder portion 54 of the cap 50 and the fuel cell 40 may occur, and sink marks (concave marks) may occur. In the present embodiment, a film-like current collecting layer 62 is formed in advance on the outer peripheral surface and the end surface of the fuel electrode layer 44. Unlike the conductive bonding layer 64 formed in the gap between the end portion 40a of the fuel cell 40 and the cap 50, the current collecting layer 62 is formed in an open space, and therefore, the current collecting layer 62 has a sink due to air entrainment or firing. Can be formed into a dense film with a substantially uniform thickness. That is, by forming the current collecting layer 62 in advance, an electrical contact area with the fuel electrode layer 44 can be secured. On the other hand, even if air remains or sinks in the conductive bonding layer 64, the contact area between the current collecting layer 62 and the conductive bonding layer 64 is only reduced. Since the current collecting layer 62 and the conductive bonding layer 64 are formed using a material having high conductivity, even if the contact area between the two becomes small due to residual air or sink marks, there is a problem with the electrical resistance between the two. It will not increase so much.

  The following experiment was conducted on the conductivity between the fuel battery cell 40 and the cap 50.

  In the fuel cell 40 of the present embodiment in which the cap 50 is assembled in the cap assembling step described above, the outer peripheral surface of the cap 50 and the end of the fuel cell 40 opposite to the mounting side of the cap 50 (fuel electrode layer) 44) and wiring was attached, and the electrical resistance was measured in a reducing atmosphere. The electric resistance was 9.4 mΩ at 700 ° C.

  On the other hand, as a comparative example, a fuel cell without the current collecting layer 62 was prepared. The fuel cell of the comparative example omits the steps S100 and S110 in the cap assembling step of FIG. 3, and the outer peripheral surface and end surface of the fuel electrode layer 44 of the fuel cell 40 and the upper surface of the bottom portion 52 of the cap 50 and the cylinder. A conductive paste made of a silver-palladium alloy is filled between the inner peripheral surface of the portion 54 and fired at 850 ° C. The fuel cell of the comparative example does not include the current collecting layer 62, and the upper surface of the bottom 52 of the cap 50 and the end surface of the end 40 a of the fuel cell 40 are electrically connected by the conductive bonding layer 64. The inner peripheral surface of the cylindrical portion 54 of the cap 50 and the outer peripheral surface of the end portion 40a of the fuel cell 40 are electrically connected. And in the fuel cell of this comparative example, wiring was attached like the fuel cell 40 of this embodiment, and the electrical resistance was measured in a reducing atmosphere. The electrical resistance was 10.2 mΩ at 700 ° C.

  According to the current collecting structure of the fuel cell 40 of the present embodiment described above, the cap 50 has the inner surface of the bottom 52 and the inner peripheral surface of the cylindrical portion 54, respectively, the end surface and the outer periphery of the end 40a of the fuel cell 40. It is fitted so as to surround the surface. A film-like current collecting layer 62 is provided on the outer peripheral surface and end surface of the end portion of the fuel electrode layer 44 (exposed portion 44 b) of the fuel battery cell 40, and the inner surface of the bottom portion 52 of the cap 50 and the inner periphery of the cylindrical portion 54. Between the surface and the current collecting layer 62, a conductive bonding layer 64 that electrically bonds both is disposed. As described above, after sufficiently securing an electrical contact area between the current collecting layer 62 provided in the form of a film and the fuel electrode layer 44, the fuel electrode layer 44 and the cap 50 are connected to the current collecting layer 62 and the conductivity. Electrical connection can be achieved through the bonding layer 64. Further, since the conductive bonding layer 64 is formed after the film-shaped current collecting layer 62 is formed first, a sufficient electrical contact area between the current collecting layer 62 and the fuel electrode layer 44 can be ensured. Even if air remains or sinks in the conductive bonding layer 64, the influence can be suppressed. As a result, the electrical conductivity between the fuel cell 40 and the cap 50 can be improved.

  In addition, since the conductive bonding layer 64 and the current collecting layer 62 are formed of the same material, the thermal stress is reduced by eliminating the difference in thermal expansion between the conductive bonding layer 64 and the current collecting layer 62 with respect to temperature changes. Both electrical connections can be kept good.

  In the present embodiment, the conductive bonding layer 64 and the current collecting layer 62 are made of the same material, but may be made of different materials. In this case, it is desirable to select materials having similar thermal expansion coefficients (for example, materials having a difference in coefficient of thermal expansion within 0.5 ppm).

  In the present embodiment, the film-like current collecting layer 62 is provided on the outer peripheral surface and the end surface of the fuel electrode layer 44 of the fuel battery cell 40. However, the present invention is not limited to this. FIG. 5 is a cross-sectional view of the end 140a of the fuel cell 140 according to another embodiment. As shown in the drawing, a current collecting layer 162 is provided on the inner peripheral surface in addition to the outer peripheral surface and the end surface that are not covered with the electrolyte layer 42 in the fuel electrode layer 44. As a result, the electrical contact area between the current collecting layer 162 and the fuel electrode layer 44 can be further increased to further secure the contact area, so that the conductivity between the fuel cell 40 and the cap 50 can be further increased. It can be made even better. Moreover, in this fuel cell 140, wiring was attached similarly to the fuel cell 40 of this embodiment, and the electrical resistance was measured in a reducing atmosphere. The electrical resistance was 9.2 mΩ at 700 ° C.

  In the present embodiment, the fuel battery cell 40 and the cap 50 are formed in a cylindrical shape, but may be formed in any shape such as a rectangular tube shape as long as it is cylindrical.

  The correspondence between the main elements of the present embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the present embodiment, the electrolyte layer 42 corresponds to an “electrolyte layer”, the fuel electrode layer 44 corresponds to an “inner electrode layer”, the oxidant electrode layer 46 corresponds to an “outer electrode layer”, and the fuel cell 40. Corresponds to the “fuel cell”, the cap 50 corresponds to the “cap”, the bottom 52 corresponds to the “bottom”, the cylindrical portion 54 corresponds to the “tubular portion”, and the current collecting layer 62 corresponds to the “first”. The conductive bonding layer 64 corresponds to a “second conductive layer”.

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to such embodiment at all, and it can implement with a various form in the range which does not deviate from the summary of this invention. Of course.

  The present invention is applicable to the fuel cell manufacturing industry.

  DESCRIPTION OF SYMBOLS 10 Power generation module, 11 Module case, 12 Raw fuel gas supply pipe, 14 Reformed water supply pipe, 16 Air supply pipe, 18 Combustion exhaust gas discharge pipe, 22 Vaporizer, 24 Reformer, 26 Fuel gas supply pipe, 28 Combustion , 30 Fuel cell stack, 32 Connection plate, 34 Fuel gas manifold, 36 Support plate, 36a Through hole, 37 Glass seal part, 38 Oxidant gas manifold, 38a Supply port, 40, 140 Fuel cell, 40a, 140a end Part, 42 electrolyte layer, 44 fuel electrode layer, 44a fuel gas flow path, 44b exposed part, 46 oxidant electrode layer, 50 cap, 52 bottom part, 54 cylindrical part, 56 projection part, 62, 162 current collecting layer, 64 conductive Adhesive bonding layer, 66 glass seal layer.

Claims (4)

A current collecting structure for a cylindrical fuel cell having a cylindrical inner electrode layer, a cylindrical outer electrode layer, and an electrolyte layer disposed between the inner electrode layer and the outer electrode layer. ,
A conductive cap fitted into an end of the fuel cell and electrically connected to the inner electrode layer;
The cap includes an annular bottom portion and a cylindrical portion extending in a cylindrical shape from the outer peripheral side of the bottom portion, and an inner surface of the bottom portion and an inner peripheral surface of the cylindrical portion are the ends of the fuel cell, respectively. It is fitted so as to surround the end surface and outer peripheral surface of the part,
A film-like first conductive layer is provided on the outer peripheral surface and the end surface of the end portion of the inner electrode layer,
A current collecting structure for a fuel cell, wherein a second conductive layer is provided between the inner surface of the bottom and the inner peripheral surface of the cylindrical portion and the first conductive layer. It is the current collection structure of the fuel battery cell according to claim 1,
The first conductive layer is also provided on an inner peripheral surface of the inner electrode layer. A current collecting structure for a fuel cell according to claim 1 or 2,
The first conductive layer and the second conductive layer are formed of the same material. Method for manufacturing current collecting structure of tubular fuel cell having tubular inner electrode layer, tubular outer electrode layer, and electrolyte layer disposed between inner electrode layer and outer electrode layer Because
Applying a conductive paste to at least the outer peripheral surface and the end surface at the end of the inner electrode layer;
Solidifying the conductive paste applied to the inner electrode layer to form a film-shaped first conductive layer;
A cap having an annular bottom portion and a cylindrical portion extending in a cylindrical shape from the outer peripheral side of the bottom portion, and an inner surface of the bottom portion and an inner peripheral surface of the cylindrical portion are end surfaces of end portions of the inner electrode layer, respectively. And a step of fitting so as to surround the outer peripheral surface;
In a state where the conductive paste is filled between the inner surface of the bottom portion of the cap and the inner peripheral surface of the cylindrical portion, and the first conductive layer, the conductive paste is solidified to form the second conductive layer. Forming, and
The manufacturing method of the current collection structure of the fuel cell containing this.

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