JP2008226789A - Horizontal-stripe type fuel battery cell and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a horizontal-stripe type fuel battery cell and its manufacturing method, capable of preventing gas leak from a solid electrolyte and restraining degradation of power generation performance. <P>SOLUTION: Of the horizontal-stripe type fuel battery cell, power generation elements 13 each having a multilayer structure with an inner side electrode, a solid electrolyte and an outer side electrode laminated sequentially are formed with a given interval in each axial length direction on a surface of a stick-type porous support of electric insulation with a gas flow channel formed inside on an axial length direction. The inner side electrode of one of the power generation element and the outer side electrode of the other power generation element adjoining to the power generation element are electrically connected, and a plurality of power generation elements are connected in series. In the horizontal-stripe type fuel battery cell, concave parts are continuously formed in the axial length direction on the surface of the porous support, the inner side electrode and an insulation precise layer 33 are buried alternatively inside the concave parts, and further, the solid electrolyte is integrally laminated on a surface of the porous support, the inner side electrode and the insulation precise layer to laminate the outer side electrode on a surface facing to the inner side electrode of the solid electrolyte. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a horizontal stripe fuel cell and a method for producing the same.

In recent years, various types of fuel cells in which a cell stack formed by connecting a plurality of fuel cells is accommodated in a storage container have been proposed as next-generation energy. As such a fuel cell, various types such as a polymer electrolyte fuel cell, a phosphoric acid fuel cell, a molten carbonate fuel cell, and a solid electrolyte fuel cell are known. In particular, solid electrolyte fuel cells have advantages such as high power generation efficiency and high operating temperatures of 700 ° C. to 1000 ° C., so that the exhaust heat can be used, and research and development are being promoted. .
FIG. 6 shows a conventional horizontally striped solid electrolyte fuel cell (see Patent Document 1), and reference numeral 61 denotes a base tube made of calcia stabilized zirconia (CSZ). A recess (groove) 62 for the fuel electrode is formed on the surface of the base tube 61. A fuel electrode 63 made of NiO / yttria stabilized zirconia (YSZ) is formed in the recess 62 by letterpress printing. On the base tube 61 including the fuel electrode 63, a solid electrolyte 64 made of YSZ, an air electrode 65 made of La _0.9 Sr _0.1 MnO ₃ , and an interconnector made of (NiCr / Al ₂ O ₃ + NiAl / Al ₂ O ₃ ). 66 and a protective film 67 made of Al ₂ O ₃ is formed.
Such a horizontal stripe type solid electrolyte fuel cell is manufactured as follows. First, CSZ, which is a base tube material, is formed into a shape provided with a recess (groove) 62 for a fuel electrode by a cold isostatic press (hereinafter referred to as CIP) method, and then calcined at 1300 ° C. to form a base tube 61. Is made.
Next, NiO / YSZ slurry, which is a fuel electrode material, is deposited on the recess 62 of the base tube 61 by letterpress printing to form the fuel electrode 63. Subsequently, a YSZ slurry that is a solid electrolyte and a La _0.9 Sr _0.1 MnO ₃ slurry that is an air electrode material are formed by concave printing, and are baked at 1300 ° C. to form the solid electrolyte 64 and the air electrode 65. Further, an interconnector 66 made of (NiCr / Al ₂ O ₃ + NiAl / Al ₂ O ₃ ) and a protective film 67 made of Al ₂ O ₃ are formed to produce a horizontal stripe type solid oxide fuel cell. .
In such a horizontal stripe type solid electrolyte fuel cell, the fuel electrode 63 is accommodated in the recess (groove) 62 of the base tube 61 and the solid electrolyte 64 is formed on the upper surface thereof. Compared with the case where the solid electrolyte 64 is formed so as to cover the upper surface, a step due to the thickness of the fuel electrode 63 does not occur in the solid electrolyte 64, and gas leakage from the solid electrolyte 64 can be suppressed.
JP-A-8-106916

In the conventional horizontal stripe type solid oxide fuel cell described above, the base tube 61 is formed with the recess 62 for accommodating the fuel electrode 63, and a portion of the base tube 61 exists between the fuel electrodes 63. As a result, insulation between adjacent fuel electrodes 63 is secured.
In such a fuel battery cell, the recess of the calcined substrate tube is filled with the fuel electrode material, a solid electrolyte molded body is formed on the surface of the calcined substrate tube and the upper surface of the fuel electrode material, and the surface of the solid electrolyte molded body is formed. When the air electrode material is printed and fired, Ca in the base tube 61 made of calcia-stabilized zirconia (CSZ) diffuses between the fuel electrode 63 and the solid electrolyte 64 to generate a highly insulating compound. There was a problem that the power generation performance deteriorated.
An object of the present invention is to provide a horizontally-striped fuel cell that can prevent a gas leak from a solid electrolyte and suppress a decrease in power generation performance, and a method for manufacturing the same.

  As a result of intensive studies to solve the above problems, the present inventors have provided a recess in the planar portion of the surface of the support, and alternately embedded the inner electrode and the dense layer of the solid electrolyte, thereby forming a solid electrolyte. In order to complete the present invention, it is found that gas leakage can be prevented without causing a step in the layer, generation of a compound having high insulation resistance can be suppressed between the solid electrolyte and the inner electrode, and reduction in power generation performance can be suppressed. It came.

That is, the horizontally-striped fuel cell according to the present invention and the manufacturing method thereof have the following configuration.
(1) The horizontally striped fuel cell according to the present invention has an inner electrode, a solid electrolyte, and an outer electrode sequentially laminated on the surface of an electrically insulating rod-like porous support having a gas flow path formed in the axial direction. The power generation elements having a multilayered structure are formed at predetermined intervals in the axial length direction, and an inner electrode of one of the power generation elements and an outer electrode of the other power generation element adjacent to the one power generation element In the horizontally striped fuel cell in which the plurality of power generation elements are electrically connected and connected in series, a recess is continuously formed in the axial direction on the surface of the porous support, and the recess The inner electrode and the insulating dense layer are alternately embedded, and the solid electrolyte is laminated on the surface of the porous support, the inner electrode and the insulating dense layer, and faces the inner electrode of the solid electrolyte. On the outer surface of the part Wherein the electrodes are stacked.
(2) The insulating dense layer is characterized by not containing Mg, Ca and Sr.
(3) The insulating dense layer is made of a solid electrolyte material.
(4) The method for producing the horizontal stripe fuel cell according to the present invention is such that a gas flow path is recessed in the axial direction on the surface of a rod-shaped porous support body made of an electrically insulating material having an axial length formed therein. Forming a plurality of inner electrode molded bodies by embedding the inner electrode material in the recess at predetermined intervals in the axial direction, the inner electrode molded body and the surface of the porous support body, and A solid electrolyte material is printed in the recesses to form an insulating dense layer molded body filled with the solid electrolyte material between the inner electrode molded bodies, and a solid electrolyte molded body is formed on the surface of the inner electrode molded body. And a step of simultaneously firing the support molded body, the inner electrode molded body, the solid electrolyte molded body, and the insulating dense layer molded body formed between the inner electrode molded bodies. To do.

According to (1), the horizontally-striped fuel cell of the present invention has a step in the solid electrolyte layer by forming a recess in the flat portion of the porous support and embedding a plurality of inner electrodes in the recess. The risk of gas leakage can be prevented without occurring, and a highly reliable horizontal stripe fuel cell can be provided. Furthermore, an insulating dense layer made of a material different from that of the porous support is formed between the inner electrodes in the recess, and elements such as Mg, Ca, and Sr used as the porous support are formed. The diffusion between the solid electrolyte layer and the inner electrode can be suppressed, the formation of a layer having a high insulation resistance can be suppressed, and the decrease in power generation performance can be suppressed.
Further, the provision of the concave portion can suppress the shift of the fuel electrode arrangement position, and it becomes easy to manufacture a cell with high dimensional accuracy, thereby enabling cost reduction and process simplification.
Further, according to (2), by forming a dense layer made of an insulating material not containing Mg, Ca, Sr between the inner electrodes in the recess, the above elements diffuse during firing, and the inner electrode and the solid electrode are solid. Since it can suppress producing | generating a compound between electrolytes, it can have high electric power generation efficiency.
Further, according to (3), by forming an insulating dense layer made of a solid electrolyte material between the inner electrodes in the recesses, elements such as Mg, Ca, Sr are diffused, and the inner electrode and the solid electrolyte Since it can suppress producing | generating a compound in the meantime, it can have high power generation efficiency. Furthermore, the number of material types used for the fuel cell can be reduced, and cost reduction and process simplification can be realized.
According to the method for producing a horizontal stripe fuel cell of the present invention, an insulating dense layer can be formed simultaneously with the formation of the solid electrolyte layer, and the insulating dense layer can be easily formed.

Hereinafter, an embodiment of a horizontal stripe fuel cell according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a partially broken perspective view showing the structure of a horizontal stripe fuel cell according to the present invention. 2 is a partially enlarged sectional view taken along line AA of FIG. The fuel battery cell 1 includes a plurality of power generating elements 13 disposed on opposite surfaces of a hollow plate-like electrically insulating porous support (hereinafter referred to as an insulating support 11) in the axial length direction (long) of the insulating support 11. A plurality of elements are arranged at predetermined intervals along the vertical direction (gas flow path forming direction), and these are connected in series via the inter-element connection member 17. A plurality of power generating elements 13 are respectively formed on the front and back surfaces of the insulating support 11 that face each other.

The power generating elements 13 adjacent to each other on the front and back surfaces of the insulating support 11 are connected in series by an inter-element connection member 17 including a first current collecting layer 17a and a second current collecting layer 17b. That is, as shown in FIG. 2, a first current collecting layer 17a is formed on a fuel electrode layer 13a (hereinafter also referred to as an active fuel electrode layer 13a) of one power generating element 13, and this first current collecting layer is formed. The periphery of the layer 17a including both ends in the axial length direction is covered with the solid electrolyte 13b in a gas-sealed state and exposed from the solid electrolyte 13b in a strip shape. The exposed portion of the first current collecting layer 17a is covered with the second current collecting layer 17b, and this second current collecting layer 17b is formed on the air electrode layer 13c of the other power generating element 13, thereby generating power. The elements 13 are electrically connected in series.
In the present embodiment, the fuel electrode has a structure in which the fuel electrode is formed in two layers of the active fuel electrode layer 13a on the solid electrolyte 13b side and the current collecting fuel electrode layer 23 on the insulating support 11 side.

  The insulating support 11 is porous, and a plurality of fuel gas passages 12 with small inner diameters are separated by partition walls 51 (see FIG. 1) and extend in the axial length direction. Is provided. The number of the gas flow paths 12 is preferably 2 to 14, for example, and more preferably 6 to 10 in terms of power generation performance and structural strength. In this way, by forming a plurality of gas flow paths 12 inside the insulating support 11, the insulating support 11 is flattened compared to the case where one large gas flow path is formed inside the insulating support 11. It is possible to increase the power generation amount by increasing the area of the power generation element 13 per volume of the fuel cell 1. Therefore, the number of cells for obtaining the required power generation amount can be reduced. In addition, the number of connection points between cells can be reduced.

By flowing fuel gas (hydrogen gas) through the gas flow path 12 and exposing the air electrode layer 13c to an oxygen-containing gas such as air, the following formula (1) is established between the active fuel electrode layer 13a and the air electrode layer 13c. The electrode reaction shown in (2) occurs, a potential difference is generated between the two electrodes, and power is generated.
That is, the electrode reaction of the following formula (1) occurs in the air electrode layer 13c, and the electrode reaction of the following formula (2) occurs in the active fuel electrode layer 13a.

  As shown in FIGS. 1 and 2, the insulating support 11 of the present invention is formed with rectangular recesses on the front and back surfaces in the axial length direction, and the recess has the same thickness as the depth and width of the recesses. In addition, fuel electrodes (active fuel electrode layer 13a, current collecting fuel electrode layer 23) and insulating dense layers 33 having a width and a width are alternately embedded in the axial direction. Thereby, the plane of the insulating support 11 and the plane of the active fuel electrode layer 13a and the insulating dense layer 33 are the same plane, and there is no step between the insulating support 11 and the active fuel electrode layer 13a when the solid electrolyte is formed. Therefore, the non-film-formed part by the conventional level | step-difference part is lose | eliminated, and the solid electrolyte layer 13b of uniform thickness is formed. As a result, gas leak can be suppressed. In addition, since the active fuel electrode layer 13a and the current collecting fuel electrode layer 23 are embedded in the recesses, the displacement of the fuel electrode can be suppressed, and it becomes easy to manufacture a cell stack with high dimensional accuracy. Reduction and process simplification can be realized. Further, since the displacement of the fuel electrode is suppressed, the displacement of the insulating support 11 on the front and back surfaces can be eliminated, and the cell warpage during firing can be suppressed.

  The depth of the recess formed in the insulating support 11 is 10 to 500 μm, and it is preferably formed at a position 0.1 to 10 mm away from both end portions in the width direction of the insulating support 11. The thickness (depth) of the recess is the same as the total thickness of the active fuel electrode layer 13a and the collector fuel electrode layer 23 so that the step does not occur in the insulating support 11 and the active fuel electrode layer 13a. It is better to set as follows.

The insulating dense layer 33 is preferably made of a material different from that of the insulating support 11, and is preferably an insulating dense layer not containing Mg, Ca, or Sr. Thereby, it can suppress that Mg, Ca, Sr, etc. which are elements used for a porous support body diffuse between the solid electrolyte layer 13b and the active fuel electrode layer 13a, and an insulation resistance is high. Since the formation of the layer can be suppressed, a decrease in power generation performance can be suppressed.
The insulating dense layer 33 is preferably made of the same material as the solid electrolyte layer 13b. Thereby, the insulating dense layer 33 and the solid electrolyte layer 13b can be simultaneously formed. At this time, as described above, there is no step between the insulating support 11 and the active fuel electrode layer 13a, so that the thickness is uniform. The solid electrolyte layer 13b is formed, and there is no variation in the power generation performance of each cell, and stable power generation can be achieved.

Hereinafter, the material of each member constituting the fuel cell 1 will be described in detail.
(Insulating support)
The insulating support 11 according to the present invention is made of Ni or Ni oxide (NiO) and a rare earth element oxide. Examples of rare earth elements constituting rare earth element oxides include Y, La, Yb, Tm, Er, Ho, Dy, Gd, Sm, and Pr. Preferably, Y ₂ O ₃ or Yb ₂ O ₃ , especially Y ₂ O ₃ .

The Ni or NiO (NiO is usually reduced by hydrogen gas and present as Ni during power generation) is 10 to 25% by volume in terms of NiO, particularly 15 to 20% by volume in the insulating support 11. It should be contained.
The thermal expansion coefficient of the insulating support 11 is usually about 10.5 to 12.5 × 10 ⁻⁶ (1 / K).

The insulating support 11 needs to be electrically insulating in order to prevent an electrical short circuit between the power generating elements 13, and it is generally desirable that the insulating support 11 has a resistivity of 10 Ω · cm or more. When the content of Ni or the like exceeds the above range, the electric resistance value tends to decrease. Further, when the content of Ni or the like is less than the above range, it is not different from the case where a rare earth element oxide (for example, Y ₂ O ₃ ) is used alone, and it is difficult to adjust the thermal expansion coefficient with the power generation element 13. Tend to be.

Further, the remaining amount other than Ni or the like is usually at least one kind of rare earth element oxide. However, other oxides such as MgO and SiO ₂ or composite oxides such as calcium zirconate may be contained in a small amount, for example, in the range of 5% by mass or less.
The insulating support 11 must be able to introduce the fuel gas in the fuel gas flow path 12 up to the surface of the active fuel electrode layer 13a, and therefore needs to be porous. In general, the open porosity should be 25% or more, especially in the range of 30-40%.

(Fuel electrode layer)
The fuel electrode layer causes the electrode reaction of the above formula (2). In the present embodiment, the active fuel electrode layer 13a on the solid electrolyte 13b side and the current collecting fuel electrode layer 23 on the insulating support 11 side. And a two-layer structure.
The active fuel electrode layer 13a on the solid electrolyte 13b side is formed of a known porous conductive ceramic. For example, it is composed of ZrO ₂ (stabilized zirconia) in which a rare earth element is dissolved, and Ni and / or NiO (hereinafter referred to as Ni or the like). As the stabilized zirconia in which the rare earth element is dissolved, the same one used for the solid electrolyte 13b described later is preferably used.

The stabilized zirconia content in the active fuel electrode layer 13a is preferably in the range of 35 to 65% by volume, and the content of Ni or the like is 65 to 35% in terms of NiO in order to exhibit good current collecting performance. % Should be in the range.
Further, the open porosity of the active fuel electrode layer 13a is preferably 15% or more, particularly preferably in the range of 20 to 40%.

The thermal expansion coefficient of the active fuel electrode layer 13a is usually about 12.3 × 10 ⁻⁶ (1 / K).
The active fuel electrode layer 13a has a thickness of 5 to 5 because it absorbs thermal stress generated due to the difference in thermal expansion from the solid electrolyte 13b and prevents cracking or peeling of the active fuel electrode layer 13a. It is desirable to be in the range of 15 μm.
In the fuel electrode layer, the current collecting fuel electrode layer 23 on the insulating support 11 side is a mixture of Ni or Ni oxide and rare earth element oxide, like the insulating support 11.

The Ni or Ni oxide (NiO is usually reduced by hydrogen gas and present as Ni during power generation) is contained in the rare earth element oxide in a range of 30 to 60% by volume in terms of NiO. Is good. By adjusting within this range, the difference in thermal expansion between the insulating support 11 and the collector fuel electrode layer 23 can be made 2 × 10 ⁻⁶ (1 / K) or less. The current collecting fuel electrode layer 23 needs to be conductive so as not to impair the flow of current, and it is generally desirable that the current collecting fuel electrode layer 23 have a conductivity of 400 S / cm or more. From the viewpoint of having good electrical conductivity, the content of Ni or the like is desirably 30% by volume or more.

The thermal expansion coefficient of the current collecting fuel electrode layer 23 is usually about 11.5 × 10 ⁻⁶ (1 / K).
In addition, the thickness of the current collecting fuel electrode layer 23 is desirably 80 μm or more from the viewpoint of improving electric conductivity.
As described above, if the fuel electrode is formed in two layers, the active fuel electrode layer 13a on the solid electrolyte 13b side and the current collecting fuel electrode layer 23 on the insulating support member 11 side, the collector electrode on the insulating support member 11 side is used. By adjusting the Ni amount or NiO amount in terms of NiO of the electrofuel electrode layer 23 within the range of 30 to 60% by volume, the thermal expansion coefficient thereof will be described later without impairing the bondability with the power generating element 13. The thermal expansion coefficient of the solid electrolyte 13b can be approached, and for example, the difference in thermal expansion between them can be made less than 2 × 10 ⁻⁶ / (1 / K). Therefore, since the thermal stress generated due to the difference in thermal expansion between the two during the production, heating, and cooling of the fuel battery cell 1 can be reduced, cracking and peeling of the fuel electrode can be suppressed. . Therefore, even when fuel gas (hydrogen gas) is flowed to generate power, the consistency of the thermal expansion coefficient with the insulating support 11 is stably maintained, and cracks due to thermal expansion differences can be effectively avoided. .

(Solid electrolyte)
The solid electrolyte 13b is composed of a dense ceramic made of stabilized ZrO ₂ composed of ZrO ₂ which was a solid solution of rare earth or an oxide thereof.
Here, as rare earth elements to be dissolved or oxides thereof, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, etc. Or these oxides etc. are mentioned, Preferably, Y, Yb, or these oxides are mentioned. The solid electrolyte 13b is a lanthanum gallate system (LaGaO ₃ ) having a thermal expansion coefficient substantially equal to that of stabilized ZrO ₂ (8 mol% Yttoria Stabilized Zirconia, hereinafter referred to as “8YSZ”) in which 8 mol% of Y is dissolved. System) solid electrolytes. The solid electrolyte 13b has a thickness of 10 to 100 μm, for example, and has a relative density (according to Archimedes method) of 93% or more, preferably 95% or more.
Such a solid electrolyte 13b has a function as an electrolyte for bridging electrons between electrodes, and at the same time has a gas barrier property to prevent leakage of fuel gas or oxygen-containing gas (gas permeation). .

(Air electrode layer)
The air electrode layer 13c is made of conductive ceramics. Examples of conductive ceramics include ABO ₃ type perovskite oxides. Examples of such perovskite oxides include transition metal type perovskite oxides, preferably LaMnO ₃ oxides, LaFeO ₃ oxides. Examples thereof include transition metal type perovskite oxides having La at the A site, such as oxides based on oxides and LaCoO ₃ oxides. More preferably, from the viewpoint of high electrical conductivity at a relatively low temperature of about 600 to 1000 ° C., a LaCoO ₃ oxide is used.
In the perovskite oxide described above, La and Sr may coexist at the A site, and Fe, Co, and Mn may coexist at the B site.
Such an air electrode layer 13c can cause the electrode reaction of the above-described formula (1).
Further, the air electrode layer 13c has an open porosity of, for example, 20% or more, and preferably 30 to 50%. If the open porosity is within the above-described range, the air electrode layer 13c can have good gas permeability.
Moreover, the thickness of the air electrode layer 13c is set in a range of 30 to 100 μm, for example. If it exists in an above-described range, the air electrode layer 13c can have favorable current collection property.

(Element connection member)
The inter-element connection member 17 electrically connects the active fuel electrode layer 13a of one power generation element 13 and the air electrode layer 13c of the other power generation element 13 adjacent to each other. 2 current collecting layers 17b, and these are electrically connected. The first current collecting layer 17a conducts the active fuel electrode layer 13a of one power generating element 13 and the second current collecting layer 13b, and the second current collecting layer 17b is connected to the first current collecting layer 17a and the other power generating element. The 13 air electrode layers 13c are electrically connected.
The inter-element connection member 17 is made of conductive ceramics, but needs to have reduction resistance and oxidation resistance because it contacts an oxygen-containing gas such as fuel gas (hydrogen gas) and air. It is.
For this reason, conductive ceramics, metal, and metal glass containing glass can be used as the inter-element connection member 17, and the lanthanum chromite perovskite oxide (LaCrO ₃ oxide) is used as the conductive ceramic. used. The first current collecting layer 17a is electrically conductive to prevent leakage of fuel gas passing through the gas flow path 12 in the insulating support 11 and oxygen-containing gas such as air passing outside the air electrode layer 13c. Ceramics must be dense and preferably have a relative density (Archimedes method) of, for example, 93% or more, particularly 95% or more. In addition, a sealing property can also be improved by interposing an appropriate bonding layer (for example, Y ₂ O ₃ ) between the end face of the first current collecting layer 17a and the end face of the solid electrolyte 13b.
The first current collecting layer 17a may have a two-layer structure of a metal layer and a metal glass layer containing glass. The metal layer is made of, for example, an alloy of Ag and Ni, and the metal glass layer is made of Ag and glass. Due to the metal glass layer, the fuel gas passing through the gas flow path 12 in the insulating support 11 leaks to the second current collecting layer 17b, and the oxygen-containing gas passes outside the air electrode layer 13c to the metal layer. Can be effectively prevented. Moreover, as the 2nd current collection layer 17b, the porous layer comprised, for example from Ag-Pd can be used.

  In the above-described example, the power generating element 13 formed on the insulating support 11 has a layer structure in which the inner electrode is the active fuel electrode layer 13a and the outer electrode is the air electrode layer 13c. However, it is of course possible to reverse the positional relationship between the two electrodes. That is, an air generating layer can be formed by laminating an air electrode layer, a solid electrolyte, and an active fuel electrode layer in this order on an insulating support. In this case, an oxygen-containing gas such as air is introduced into the gas flow path of the insulating support, and the fuel gas is supplied to the outer surface of the active fuel electrode layer that is the outer electrode.

(Production method)
Next, a method for manufacturing the horizontal stripe fuel cell described above will be described with reference to FIGS.

First, the insulating support body molded body 41 is produced. As a material for the insulating support molded body 41, MgO powder having an average particle diameter (D ₅₀ ) (hereinafter simply referred to as “average particle diameter”) on a volume basis is 0.1 to 10.0 μm, and if necessary, thermal expansion is performed. Ni powder, NiO powder, Y ₂ O ₃ powder, rare earth element stabilized zirconia powder (YSZ), etc. are mixed at a predetermined ratio and mixed for coefficient adjustment or bonding strength improvement, and thermal expansion after mixing The coefficient is adjusted so as to substantially match that of the solid electrolyte 13b. This mixed powder is mixed with a solvent composed of a pore agent, a cellulose organic binder, and water, extruded, and formed into a hollow plate shape having a gas flow path 42 therein, and a groove is formed in a flat plate portion. A flat insulating support molded body 41 having a flat shape (FIG. 3B) is prepared, dried, and calcined at 900 ° C. to 1100 ° C. As shown in FIG. 3B, the gas flow path 42 and the recess (groove) are formed in the same direction (axial length direction).

Next, a fuel electrode layer and a solid electrolyte are produced. First, for example, NiO powder, Ni powder, and YSZ powder are mixed, a pore agent is added thereto, an acrylic binder and toluene are mixed to form a slurry, and the slurry is applied by a doctor blade method and dried. Then, an active fuel electrode layer tape 43a having a thickness of 5 to 50 μm is produced (FIG. 4A).
Next, in the same manner as the active fuel electrode layer tape 43a, for example, NiO powder, Ni powder, and rare earth element oxide such as Y ₂ O ₃ are mixed, a pore agent is added thereto, an acrylic binder, Toluene is mixed to form a slurry, and the slurry is applied by a doctor blade method and dried to produce a current collecting fuel electrode layer tape 43 having a thickness of 80 to 200 μm. The active fuel electrode layer tape 43a is attached to the current collecting fuel electrode layer tape 43 (FIG. 4B). The bonded tape (inner electrode molded body) is cut in accordance with the shape of the power generating element 13 (FIG. 4C).

Thereafter, as shown in FIG. 4 (d), the current collecting fuel electrode layer tape 43 to which the active fuel electrode layer tape 43 a is attached is placed in the recess (groove) of the calcined insulating support molded body 41. Affixed in a horizontal stripe at a predetermined interval. At this time, one current collecting fuel electrode layer tape 43 and the other current collecting fuel electrode layer tape 43 are arranged with an interval of 3 to 20 mm in width. Further, the thickness of the collector fuel electrode layer tape 43 to which the active fuel electrode layer tape 43a is attached is the same as the depth of the recess, and the surface of the active fuel electrode layer tape 43a is an insulating support in which no recess is formed. The same plane as the plane of the molded body 41 is used.
Next, the active fuel electrode layer tape 43a and the current collecting fuel electrode layer tape 43 are dried and then calcined in a temperature range of 900 to 1100 ° C. (FIG. 4D). Then, the masking tape 21 is attached to the portion of the active fuel electrode layer 43a where the first current collecting layer 47a is to be formed (FIG. 4 (e)).

  Next, this laminate is immersed in a solid electrolyte solution that is a slurry obtained by adding an acrylic binder and toluene to 8YSZ, and is taken out from the solid electrolyte solution. By this dipping, a layer of the solid electrolyte 43b is applied to the entire surface, and an insulating dense layer molded body is also formed between the collector fuel electrode layer tape 43 (inner electrode molded body) to which the active fuel electrode layer tape 43a is attached. 53, a layer made of a solid electrolyte material is formed. In this state, baking is performed at 1150 to 1200 ° C. for 2 to 4 hours. During this baking, the layer of the masking tape 21 and the solid electrolyte 43b applied thereon can be removed (FIG. 4 (f)).

Next, the slurry was mixed with lanthanum cobaltite (LaCoO ₃₎ and isopropyl alcohol by printing, to form the air electrode layer 43c having a thickness of 10 to 100 [mu] m. Then, baking is performed at 950 to 1150 ° C. for 2 to 5 hours (FIG. 4G).
And the sheet | seat of the metal layer which consists of Ag / Ni is affixed on the part which wants to form the 1st current collection layer 47a, Furthermore, the sheet | seat of the metal glass layer containing Ag and glass is affixed (FIG.4 (g)), and then , Heat treatment is performed at 1000 to 1200 ° C.
Finally, the second current collecting layer 47b can be applied at a predetermined position to obtain a horizontally striped fuel cell (FIG. 4 (i)).

In the above embodiment, the embodiment in which the layer of the solid electrolyte 43b is formed by dipping has been described. However, in the present invention, the slurry made of the solid electrolyte material is taped, and this tape is formed into the active fuel electrode layer tape 43a and the insulating support body. It may be wound around the surface of the body 41. In this case, as shown in FIG. 5, a solid electrolyte sheet (insulating dense layer molded body 53) and a current collecting fuel electrode layer tape 43 to which an active fuel electrode layer tape 43a is attached are connected on a transfer sheet in advance. However, it is necessary to transfer this, or to fill the current collecting fuel electrode layer tape 43 to which the active fuel electrode layer tape 43a is attached with the slurry of the solid electrolyte material.
In addition, as for the lamination method of each layer described above, any lamination method of tape lamination, paste printing, dip, and spray spraying may be used. Preferably, the drying process at the time of lamination is short, and each layer is laminated by dipping from the viewpoint of shortening the process.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the above example, the insulating support 11 is described as a hollow plate having a plurality of gas flow paths 12 inside, but the insulating support 11 may be cylindrical and the number of gas flow paths 12 There may be only one, and any material may be used as long as it is an insulator. Further, in the above embodiment, the case where the active fuel electrode layer 13a and the current collecting fuel electrode layer 23 are provided has been described. In addition, various modifications can be made within the scope of the present invention.

It is a partially broken perspective view which shows the structure of the fuel battery cell 1 of this invention. 2 is a partially enlarged sectional view taken along line AA of FIG. (A) is a manufacturing-process figure of the insulation support body of this invention, (b) is a perspective view of an insulation support body. It is a manufacturing-process figure of the fuel battery cell of this invention. It is a perspective view of the tape which consists of a fuel electrode layer and an insulating dense layer before laminating | stacking on the insulating support body of this invention. It is sectional drawing which shows the structure of the conventional fuel cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell 11 Insulation support body 12 Fuel gas flow path 13 Electric power generation element (13a: Active fuel electrode layer, 13b: Solid electrolyte, 13c: Air electrode layer)
17 Inter-element connection member (17a: first current collecting layer, 17b: second current collecting layer)
23 current collecting fuel electrode layer 33 insulating dense layer

Claims (4)

On the surface of the electrically insulating rod-like porous support body in which the gas flow path is formed in the axial direction inside,
A power generation element having a multilayer structure in which an inner electrode, a solid electrolyte, and an outer electrode are sequentially laminated is formed at predetermined intervals in the axial length direction,
A horizontally striped fuel cell in which an inner electrode of one of the power generating elements and an outer electrode of the other power generating element adjacent to the one power generating element are electrically connected, and the plurality of power generating elements are connected in series In the cell
Concave portions are continuously formed in the axial length direction on the surface of the porous support, and the inner electrodes and insulating dense layers are alternately embedded in the concave portions, and the solid electrolyte is the porous support, A horizontal stripe fuel cell, wherein the fuel cell is stacked on the inner electrode and the insulating dense layer, and the outer electrode is stacked on an outer surface of the solid electrolyte facing the inner electrode.   The horizontal stripe fuel cell according to claim 1, wherein the insulating dense layer does not contain Mg, Ca, and Sr.   3. The horizontal stripe fuel cell according to claim 1, wherein the insulating dense layer is made of a solid electrolyte material. Forming a recess in the axial direction on the surface of the rod-shaped porous support molded body made of an electrically insulating material in which the gas flow path is formed in the axial direction;
A step of embedding an inner electrode material in the recess at predetermined intervals in the axial length direction to form a plurality of inner electrode molded bodies;
A solid electrolyte material is printed on the inner electrode molded body and the surface of the porous support molded body and in the recesses, thereby forming an insulating dense layer molded body filled with the solid electrolyte material between the inner electrode molded bodies. Forming a solid electrolyte molded body on the inner electrode molded body surface;
A step of simultaneously firing the support molded body, the inner electrode molded body, the solid electrolyte molded body, and the insulating dense layer molded body formed between the inner electrode molded bodies. Manufacturing method of fuel cell.

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