JP2005166422A - Solid oxide fuel battery cell, cell plate, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid oxide fuel battery cell which is superior in strength of a substrate, high in rigidity of the substrate even when its thickness is reduced, capable of preventing exfoliation or crack of an electrode or an electrolyte layer caused by thermal expansion, and capable of current collection without causing current collecting loss or short circuit; and to provide a cell plate and a manufacturing method of these fuel battery cell and cell plate. <P>SOLUTION: A first electrode layer 3 is formed by filling a first electrode material in the upper face side of a battery element forming portion of a porous substrate 2, and a porous insulative material 7 having gas-permeability is filled in the lower face side. In the upper face side of the peripheral portion except the battery element forming portion, an insulative layer 8 is formed by filling a gas-impermeable insulative material therein. In the lower face side, a gas-impermeable conductive material 9 is filled in. On the upper face side of the porous substrate 2, an electrolyte layer 4 extending to the peripheral insulative layer 8 is formed on the first electrode layer 3 which is formed in the battery element forming portion, and a second electrode layer 5 is formed on the electrolyte layer 4. On the second electrode layer 5, a current collecting layer 6 extending to the insulative layer 8 is formed in a mesh shape. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a substrate-supported solid oxide fuel cell in which a cell element in which an electrolyte composed of a solid oxide is sandwiched between an air electrode and a fuel electrode is supported by a porous metal substrate having gas permeability. The present invention relates to a cell and a cell plate for a solid oxide fuel cell, and a method for manufacturing such a cell and cell plate.

  A solid oxide fuel cell (SOFC) has, as basic components, a solid oxide as an electrolyte, and a fuel electrode and an air electrode arranged to face each other with the solid electrolyte made of the oxide interposed therebetween. In addition, by supplying a fuel gas such as hydrogen to the fuel electrode side and an oxidizing gas such as air to the air electrode side, DC power based on an electrochemical reaction can be obtained.

In general, in a solid oxide fuel cell, since reducing the internal resistance of the battery leads to improvement in battery performance, various means for reducing the internal resistance have been studied.
This internal resistance is dominated by electrolyte resistance and reaction resistance, of which reaction resistance is affected by various factors such as material elements and electrode microstructure, while electrolyte resistance is the electrical conductivity of the electrolyte material and Since it is influenced by the film thickness, a fuel electrode support type cell has been proposed as a cell structure capable of reducing the thickness of the electrolyte and reducing the resistance of the electrolyte portion (see, for example, Patent Document 1).
That is, as shown in FIG. 6 (a), the fuel electrode-supporting cell has an electrolyte layer 52 made of a solid oxide and an air electrode layer on a fuel electrode substrate 51 having a porous structure with gas permeability. In the cell, since the charge transfer direction is the film thickness direction, the resistance of the electrolyte can be reduced by reducing the film thickness of the electrolyte layer 52.

On the other hand, a porous metal support cell using a ductile metal material substrate is known as compared with a fuel electrode support cell using a fuel electrode made of a ceramic material as a substrate (see, for example, Patent Document 2). .
As shown in FIG. 6B, the porous metal supporting cell has a structure in which a fuel electrode layer 56, an electrolyte layer 52, and an air electrode layer 53 are sequentially formed on a porous metal substrate 55 made of, for example, stainless steel. Compared to the fuel electrode substrate 51 made of the ceramic material shown in FIG. 6A, the thickness of the substrate 55 can be reduced, so that a small fuel cell can be easily constructed and the cell Since the surrounding is a metal material, various metal processing methods can be applied to the connection between cells when stacking, and furthermore, a metal substrate can be used as a current collector, reducing current collection loss. be able to.
JP 2002-25576 A Japanese Patent Laid-Open No. 11-162483

However, the above fuel electrode support type cell requires a plate thickness of about 1 to 5 mm from the viewpoint of the strength of the substrate supporting the thin film electrolyte 52, and a plurality of cells having such a structure are stacked and assembled into a fuel. When assembling a battery stack, the thickness of the substrate may be increased, resulting in an increase in the size of the stack, which may be an obstacle to configuring a small fuel cell.
Although the thinning of the fuel electrode substrate has been studied by improving the ceramic forming technology, the fuel electrode substrate is required to be gas permeable, so it must be a porous substrate and ensure strength. However, it is extremely difficult to reduce the thickness of the sheet.
In addition, as another type of electrode supporting cell, it is conceivable to use an air electrode as a supporting substrate, but basically has the same problem.

On the other hand, porous metal-supported cells have flexible joints when stacked due to the flexibility of the substrate, but on the other hand, the rigidity of the cells is low, and the outer periphery of the cells is easily damaged during stacking. In addition, the ceramic material formed on the porous metal substrate may crack or peel off when the cell is heated or cooled due to the difference in thermal expansion coefficient between the metal material and the ceramic material such as the electrolyte layer or electrode layer. There is a problem in strength that it is easy to do.
Further, in the porous metal support type cell, the porous metal substrate serves as one electrode due to its structure, and the structure shown in FIG. 5 functions as a current collector for the fuel electrode. When assembling and assembling the fuel cell stack, it is necessary to separately install a felt-like member having electrical conductivity as a current collector for the air electrode, and the number of parts increases, and the current collector for the air electrode and the metal substrate Consideration of short circuit prevention is necessary. Furthermore, in order to ensure current collection from the air electrode, it is necessary to strongly press the current collector against the air electrode, which may damage the cell. In addition, it is necessary to install a large number of current collectors, and there is a problem that these current collectors can serve as ventilation resistance when the oxidant gas (air) is introduced during operation.

  The present invention has been made in view of the above-described problems in conventional solid oxide fuel cell cells. The object of the present invention is to provide excellent substrate strength, high substrate rigidity even when thinned, and heat resistance. Provided is a solid oxide fuel cell that can prevent electrode and electrolyte layers from peeling and cracking due to expansion and can collect current without causing a current collection loss or short circuit. Another object of the present invention is to provide a fuel cell plate having two-dimensionally arranged cells, and a fuel cell and a method of manufacturing the cell plate.

  A cell for a solid oxide fuel cell according to the present invention is a substrate-supporting cell formed by forming a battery element having a laminated structure in which a solid oxide electrolyte layer is sandwiched between a first electrode layer and a second electrode layer on a porous metal substrate. The first electrode material is embedded on the upper surface side of the battery element forming portion of the porous substrate to form the first electrode layer, and the porous insulating material having gas permeability is formed on the lower surface side. A gas-impermeable insulating material is embedded on the upper surface side of the porous substrate other than the battery element forming portion to form an insulating layer, and a gas-impermeable conductive material is embedded on the lower surface side. An electrolyte layer is formed on the upper surface side of the porous substrate from the first electrode layer formed in the battery element forming portion to the surrounding insulating layer, and further on the electrolyte layer. The second electrode layer is formed and the second electrode layer The current collecting layer made of a conductor is formed in a mesh shape across the insulating layer, and the solid oxide fuel cell plate according to the present invention is such that the fuel cell is substantially perpendicular to the stacking direction. It is characterized in that a plurality of two-dimensionally connected directions are integrated.

  The method for producing a solid oxide fuel cell according to the present invention is suitable for producing the above solid oxide fuel cell or cell plate, and [1] a battery element in a porous metal substrate. A step of filling the gas impermeable conductive material on the lower surface side of the portion other than the formation portion, and [2] a step of filling the gas impermeable insulating material on the upper surface side of the portion other than the battery element formation portion, and [3 A step of filling a porous metal substrate with a porous insulating material on a lower surface side of a battery element forming portion, and [4] a porous material filled with a gas impermeable conductive material, a gas impermeable insulating material and a porous insulating material. A step of pre-firing the metal substrate, [5] a step of forming a first electrode layer on the upper surface side of the battery element forming portion, and [6] an electrolyte layer being formed on the upper surface side of the first electrode layer. [7] a second electrode layer on the upper surface of the electrolyte layer Forming, it is characterized by comprising the step of forming a collector layer in a mesh form on the top surface [8] The second electrode layer.

  In the solid oxide fuel cell or cell plate of the present invention, the first electrode material is embedded in the battery element forming portion on the upper surface side of the porous metal substrate, and the electrolyte layer and the second electrode layer are formed thereon. In addition, the gas permeable (porous) or gas impermeable insulating material and conductive material are embedded in the other portions of the porous metal substrate depending on the portion. While the rigidity is improved, the thermal expansion coefficient of the entire substrate can be brought close to the thermal expansion coefficient of the electrode material or the electrolyte material, and cracking or peeling of the electrode layer or the electrolyte layer due to thermal shock can be prevented. Further, since the electrical contact between the first electrode layer and the porous metal substrate is ensured, the porous metal substrate can be used as a current collector on the first electrode side. On the upper surface side, a gas-impermeable insulating material is embedded in the outer peripheral portion of the first electrode layer to form a dense insulating layer, and the electrolyte layer extends from the first electrode layer to the surrounding insulating layer. Since the current collecting layer is formed in a mesh shape from the second electrode layer to the insulating layer on the second electrode layer formed on the electrolyte layer, the current collecting layer is formed. While the electrical layer, the first electrode layer, and the porous metal substrate are kept in an insulating state, the electrical connection state with the second electrode layer is ensured. Can be used as a current collector on the 2 electrode side, current collection loss is reduced, and battery output can be taken out easily Become a thing.

  Moreover, according to the manufacturing method of the present invention, the insulating material and the conductive material having gas permeability or impermeability are respectively provided on the upper surface side and the lower surface side of the battery element forming portion of the porous metal substrate and other portions. After embedding and firing, the first electrode layer, the electrolyte layer, the second electrode layer, and the mesh-like current collecting layer are formed on the upper surface side of the battery element forming portion. The excellent effect that the cell and the cell plate for a physical fuel cell can be manufactured without difficulty and at low cost is brought about.

  Hereinafter, the solid oxide fuel cell of the present invention will be described in more detail.

In the description of the present specification and claims, “%” means mass percentage unless otherwise specified.
Further, in this specification, for convenience of explanation, one surface of each layer such as a substrate or an electrolyte layer is referred to as an “upper surface (or front surface)” and the other surface is referred to as a “lower surface (or back surface)”. It is merely a relative positional relationship, and does not necessarily indicate the vertical relationship in the usage state. Depending on the situation, the “upper surface” may face downward, or may be vertical or slanted. May be used in the Therefore, it goes without saying that configurations in which these are mutually replaced are also included in the scope of the present invention.

1A and 1B are a cross-sectional view and a plan view showing an example of an embodiment of a solid oxide fuel cell according to the present invention, and the solid oxide fuel cell 1 shown in FIG. Are formed in the central portion of the porous metal substrate 2 made of, for example, Ni or stainless steel, that is, the cell element forming portion, for example, the fuel electrode layer 3 as the first electrode layer, the electrolyte layer 4 made of solid oxide, The air electrode 5 as two electrode layers is laminated in this order, and a mesh-like current collecting layer 6 made of a conductive material is further formed thereon.
The cell plate for a solid oxide fuel cell of the present invention has a large number of cells as described above formed in a plane direction on a single porous metal substrate, and these cells are two-dimensionally connected and integrated. It has a structured structure.

The fuel electrode layer 3 (first electrode layer) is embedded on the upper surface side of the battery element forming portion, which is the central portion of the porous metal substrate 2, and the fuel electrode layer 3 of the porous metal substrate 2. A porous insulating material such as a ceramic material having gas permeability is embedded in the lower portion of the lower portion.
On the other hand, with respect to the portion other than the battery element forming portion of the porous metal substrate 2 (the outer peripheral portion of the battery element forming portion), a dense insulating material having gas impermeability is embedded in the upper surface side portion in the drawing. In addition, an insulating layer 8 is formed, and a dense gas-impermeable conductive material 9 such as metal is embedded in a lower surface side portion in the drawing.

  The electrolyte layer 4 is straddled on the fuel electrode layer 3 embedded in the cell element forming portion in the center of the substrate 2 so as to extend from the fuel electrode layer 3 to the surrounding insulating layer 8 ( The current collecting layer 6 is further formed on the air electrode 5 formed on the electrolyte layer 4 so as to straddle the insulating layer 8 from the air electrode layer 5. .

In the fuel cell 1 of the present invention having the above structure, the lower part of the battery element forming portion occupying most of the cell is filled with a porous insulating material 7 such as a ceramic material having gas permeability. Therefore, rigidity can be imparted to the porous metal substrate 2, and even when the substrate 2 is thinned, it is not easily deformed.
Further, by filling with such a material, the thermal expansion of the entire substrate 2 can be made closer to the thermal expansion coefficient of the electrolyte material or the electrode material, and the electrode layer or the electrolyte layer accompanying the repeated heating and cooling can be made. It is possible to prevent cracking and peeling.

Further, the presence of the porous insulating material 7 in the lower portion makes it possible to make the fuel electrode layer 3 much thinner than a general fuel electrode supporting cell, and to oxidize and reduce Ni of the fuel electrode material. The influence of the accompanying expansion / contraction can be reduced.
In addition, in terms of battery performance, it is possible to completely fill the battery element forming portion of the substrate 2 with an electrode material. However, since the electrode material is generally expensive and heavy, the lower part of the battery element forming portion is Filling with a porous insulating material 7 having gas permeability is desirable from the viewpoint of cost and weight reduction.

  Furthermore, since the outer peripheral portion of the porous metal substrate 2 is filled with the gas-impermeable insulating material and the conductive material, the synthesis can be improved in the same manner, and it can be suitably used as a joint when stacking. In addition, since the insulating and conductive materials are gas-impermeable, gas cross-leakage between the fuel electrode side and the air electrode side is prevented.

  Further, when the power generation output is taken out from both electrodes, it is required to reduce the contact resistance between the electrode and the current collector. In the fuel cell 1 of the present invention, the fuel electrode 3 (the first electrode) 1) and the substrate 2 are in electrical contact with each other, the porous metal substrate 2 can be used as a fuel electrode (first electrode layer) side current collector.

On the other hand, as a current collector on the air electrode 5 (second electrode layer) side, a mesh-shaped current collecting layer 6 formed on the air electrode 5 can be used.
That is, in the fuel cell 1 described above, an insulating layer 8 is formed by filling a gas impervious insulating material on the upper surface portion of the outer peripheral portion of the battery element forming portion, and the electrolyte layer 4 is the fuel electrode layer. 3 and the insulating layer 8, the air electrode 5 and the mesh current collecting layer 6, the fuel electrode 3 and the porous metal substrate 2 are kept in an insulated state, and the air electrode side It will function as a current collector.

In the solid oxide fuel cell 1, the material of the porous metal substrate 2 is not only nickel, but also various stainless steels, heat-resistant Ni-based alloys such as Inconel and Hastelloy, Fe-Ni alloys such as amber, etc. What consists of a metal material containing the at least 1 sort (s) of element chosen from the group which consists of Ni, Fe, and Cr can be used conveniently.
As the porous metal substrate 2, not only one obtained by sintering fine metal particles as shown in FIG. 1 but also one obtained by solidifying a fibrous metal into a felt shape as shown in FIG. 2 is used. It is also possible.

  The gas-impermeable conductive material 9 embedded in the lower surface side of the portion (outer peripheral portion) other than the battery element forming portion of the porous metal substrate 2 can be selected from the above metal materials similar to the porous metal substrate 2, It is more desirable to use the same type of metal material as the porous metal substrate 2.

The gas impermeable insulating material that is embedded in the upper surface side portion (outer peripheral portion) other than the battery element forming portion of the porous metal substrate 2 to form the insulating layer 8 is not particularly limited and can be arbitrarily selected. However, it is preferred to use a ceramic material, for example a mixture of one or both of alumina and zirconia and up to 10% borosilicate glass.
Further, the porous (gas permeable) insulating material 7 filled in the lower surface portion of the battery element forming portion in the porous metal substrate 2 is not particularly limited. Similarly, one or both of alumina and zirconia and borosilicate are used. Preference is given to using a mixture of glasses. In this case, for example, the ceramic material is made porous by applying the slurry as a slurry obtained by mixing the above material with resin or carbon fine particles, followed by firing, so that gas permeability can be imparted.

Examples of the material of the fuel electrode layer 3 include metal materials such as Pt, Ni, and Cu, Ni-SDC (samarium-doped ceria), Ni-YSZ (yttria stabilized zirconia), and Ni-CGO (cerium-gallium composite). oxide), cermet material such as Cu-CeO ₂ (ceria), or can be used a mixture of these materials.
The material of the air electrode layer 5, Pt, other metal materials such as _{Ag, LSM (La 1-X} Sr X MnO 3), LCM (La 1-X Ca X MnO 3), LSC (La 1- A composite oxide such as _X Sr _X CoO ₃ ) or SSC (Sm _1-X Sr _X CoO ₃ ) can be used.

  Furthermore, as the electrolyte layer 4, YSZ, SSZ (scandium stabilized zirconia), SDC, LSGM (lanthanum gallate), etc. can be used, for example.

Next, the manufacturing method of the cell for solid oxide fuel cells of this invention is demonstrated.
FIG. 3 (a) shows an example of a porous metal substrate used in the solid oxide fuel cell of the present invention. The porous metal substrate 2 is formed by sintering fine particles made of the metal material as described above. It has a large number of pores (vents). In addition, as such a porous metal substrate, as described above, a substrate obtained by pressing and sintering a small-diameter metal fiber can also be used.

First, the outer peripheral portion of the porous metal substrate 2, that is, the lower surface side of the portion other than the battery element forming portion occupying the central portion in the drawing, that is, the back side outer peripheral portion on the side where the battery elements are laminated in the subsequent process A gas-impermeable conductive material 9 is embedded, and the vent hole in the part is sealed. Specifically, the porous portion of the substrate 2 is filled and solidified with a slurry, paste, or the like containing fine metal particles using a method such as dispenser, roll coater, or screen printing.
The material of such metal fine particles can be arbitrarily selected, but the same material as that of the substrate 2 is preferably used.

Next, as shown in FIG. 3 (b), dense gas impermeability is formed on the upper surface side of the outer peripheral portion of the porous metal substrate 2, that is, in the upper part of the portion where the gas impermeable conductive material 9 is embedded. Insulating layer 8 is similarly embedded and sealed to form insulating layer 8.
The gas-impermeable insulating material at this time is not particularly limited, but as described above, a mixture of alumina (Al ₂ O ₃ ) and / or zirconia (ZrO ₂ ) and 10% or less borosilicate glass should be used. Is desirable.

Next, as shown in FIG. 3 (c), the gas permeability is applied to the central portion of the substrate 2 whose outer peripheral portion is sealed with the dense conductive material 9 and the insulating material, that is, the lower surface side portion of the battery element forming portion. A porous insulating material 7 having the following is embedded.
Such a porous insulating material 7 can be arbitrarily selected, but it is desirable to use a ceramic material, for example, a mixture of alumina and / or zirconia and borosilicate glass. Specifically, slurry or paste containing the above ceramic material together with resin or carbon fine particles is filled and solidified in the central porous portion of the substrate 2 by using a method such as dispenser, roll coater, or screen printing.

  Then, the porous metal substrate 2 in which the central portion as the battery element forming portion and the outer peripheral portion thereof are filled with the respective materials is temporarily fired in an inert atmosphere, and the resin and carbon fine particles contained in the central portion are burned. The portion is made porous to impart gas permeability, and the porous metal substrate 2 and each filler material are adhered and cured.

After the preliminary firing, as shown in FIG. 3 (d), in the central portion of the substrate 2, the upper surface side of the battery element forming portion, that is, the inner portion of the insulating layer 8 and immediately above the layer made of the porous insulating material After embedding the fuel electrode material and forming one electrode layer, for example, the fuel electrode layer 3, the electrolyte layer 4 is formed on the electrode layer 3 from the fuel electrode layer 3 to the surrounding insulating layer 8. The fuel electrode layer 3 and the electrolyte layer 4 are co-fired therein.
In this way, by forming the dense electrolyte layer 4 so as to protrude from the fuel electrode layer 3 to the insulating layer 8 side, gas leakage from the fuel electrode side to the air electrode side can be prevented. As a method for forming the fuel electrode layer 3 and the electrolyte layer 4, a method such as screen printing, spray coating, or vacuum film formation can be used.

  After firing, an air electrode layer 5 is formed on the electrolyte layer 4 as shown in FIG. As the film formation method at this time, a method such as vacuum film formation such as screen printing, spray coating, sputtering, or vapor deposition can be used as described above.

1 (a) and 1 (b), the entire upper surface of the substrate 2 on which the fuel electrode layer 3, the electrolyte layer 4 and the air electrode layer 5 (battery element) are laminated is made of a conductive material. A current collecting layer 6 having a mesh portion is formed, whereby a solid oxide fuel cell 1 as shown in FIG. 1 is completed.
At this time, the mesh portion of the current collecting layer 6 can be easily formed by using a mask pattern during film formation. In addition, when the thing made from the above metal fibers is used as the porous metal substrate 2, the structure as shown in FIG. 2 is obtained.

In the above manufacturing process, an example in which the fuel electrode layer is formed as the first electrode layer has been shown. However, the air electrode layer is first formed as the first electrode layer, and the fuel electrode layer is formed on the electrolyte layer 4. A layer may be deposited.
Further, in the above manufacturing process, sealing slurry, fuel electrode paste, etc. are sequentially applied and fired on a substrate prepared in advance by firing metal particles and metal fibers. It is also possible to employ a method of using a sheet adjusted so as to have a texture structure, applying the above layers to the sheet, integrating them, and firing.

  Hereinafter, the present invention will be specifically described based on examples. In addition, this invention is not limited only to these Examples.

(Example 1)
First, as the porous metal substrate 2, a sintered substrate made of ferritic stainless steel (SUS430: Fe-17% Cr) having an average particle diameter of 5 μm, an average pore diameter of 50 μm, and a thickness of 200 μm was prepared (FIG. 3). (See (a)).

Next, a slurry containing nickel fine particles having an average particle diameter of 5 μm as a gas-impermeable conductive material 9 is filled in the lower surface side portion of the outer peripheral portion excluding the battery element forming portion which is the central portion of the substrate 2 by a screen printing technique. Then, it heated at 200 degreeC in air | atmosphere, and the solvent component contained in a slurry was volatilized.
Furthermore, the upper surface portion of the outer peripheral portion of the substrate 2 contains alumina fine particles (90%) having an average particle size of 0.5 μm and borosilicate glass (10%) having a melting point of 580 ° C. as a gas impermeable insulating material. The slurry was filled by screen printing, and similarly heated to 200 ° C. in the atmosphere to volatilize the solvent component contained in the slurry, thereby forming the insulating layer 8 (see FIG. 3B).

Next, alumina fine particles (40%) having an average particle diameter of 0.5 μm and an average particle diameter of 0. In a slurry containing 8 μm zirconia fine particles (55%) and borosilicate glass (5%) having a melting point of 580 ° C., graphite having an average particle diameter of 20 μm with respect to 100 parts by weight of the alumina fine particles, zirconia fine particles and borosilicate glass. After the slurry added with 20 parts by weight of the particles was filled by screen printing, it was similarly heated to 200 ° C. in the atmosphere to volatilize the solvent component contained in the slurry (see FIG. 3C).
And as mentioned above, the board | substrate 2 which filled each material with the center part which is a battery element formation part, and its outer peripheral part was temporarily sintered at 600 degreeC in argon atmosphere.

Next, the fuel electrode containing NiO (55%) and YSZ (45%) on the upper surface side portion of the central battery element forming portion of the substrate 2 after the preliminary sintering, that is, on the layer made of the porous insulating material 7. After filling the paste with the screen printing method, similarly, heating to 200 ° C. in the atmosphere to volatilize the solvent component contained in the paste, and then further depositing the electrolyte paste containing YSZ fine particles on the screen printing After coating by the technique, the solvent component in the paste was volatilized at 200 ° C. in the atmosphere.
The porous metal substrate 2 coated with the fuel electrode material and the electrolyte material was sintered at 1300 ° C. in an argon atmosphere to form the fuel electrode layer 3 and the electrolyte layer 4 having a thickness of 60 μm and 30 μm, respectively. (See FIG. 3 (d)).

  On the substrate 2 after sintering, an air electrode paste containing LSM fine particles is applied by screen printing so as to form an air electrode layer 5 with a film thickness of 30 μm, and then the solvent component in the paste at 200 ° C. in the atmosphere. Was volatilized (see FIG. 3 (e)).

  Further, a current paste including Ag and Ni fine particles is applied to the entire upper surface of the substrate 2 to which the air electrode layer 5 is applied, using a mask having an 80-mesh grid pattern by a similar screen printing technique. Then, after applying to a film thickness of 10 μm, the current collecting layer 6 is formed by sintering at 1100 ° C. in an argon atmosphere, and the solid oxide form as shown in FIGS. A fuel cell 1 was obtained.

(Example 2)
As the porous metal substrate 2, a metal fiber (Fe-20Cr-2Al) sintered body having an average wire diameter of 30 μm and having an average pore diameter of 60 μm and a thickness of 100 μm is used. The same operation as in Example 1 was repeated to produce a solid oxide fuel cell 1 of this example.

(Example 3)
Using the solid oxide fuel cell 1 shown in Example 1, a cell plate as an aggregate was produced.
4 and 5 are a plan view and a cross-sectional view of a cell plate for a solid oxide fuel cell according to this example. The cell plate 10 for a fuel cell is a single fuel electrode side cell plate substrate 11. Nine solid oxide fuel cell units 1 described in Example 1 above are installed on the air electrode side of these nine fuel cell units 1 and two air electrode side cell connectors 12 is arranged.

As shown in the figure, the nine cells 1 are held by the fuel electrode side cell plate substrate 11 and separated into the fuel electrode side and the air electrode side. The fuel electrode side is electrically connected by the fuel electrode side cell plate substrate 11, and the air electrode side is electrically connected by the air electrode side cell connector 12.
Here, the fuel electrode side cell plate substrate 11 is made of a stainless steel plate having a thickness of 150 μm with a Ni plating film having a thickness of 20 μm, and has nine openings for installing the cells 1 for solid oxide fuel cells, respectively. It has a portion 11a.
On the other hand, the air electrode side cell connector 12 is formed of a stainless steel plate having a thickness of 100 μm provided with a 30 μm Ag plating film.

The fuel electrode side cell plate substrate 11 and the Ni gas-impermeable conductive material portion of each solid oxide fuel cell 1 are pressurized and heated at 980 ° C. in a vacuum to obtain a good bonded state. be able to.
In addition, the air electrode side cell connector 12 and the Ag—Ni current collecting layer 6 of the solid oxide fuel cell 1 can be bonded to each other by being pressurized and heated at 840 ° C. in a vacuum. .

It is sectional drawing (a) and a top view (b) which show an example of the structure of the cell for solid oxide fuel cells of this invention. It is sectional drawing which shows the other example of the structure of the cell for solid oxide fuel cells of this invention. (A)-(e) is sectional drawing which shows order for the manufacturing process of the cell for solid oxide fuel cells of this invention later on. It is a top view which shows the structure of the cell board for solid oxide fuel cells of this invention. It is sectional drawing of the cell board for solid oxide fuel cells shown in FIG. It is a cross-sectional photograph which shows a fuel electrode support type cell (a) and a porous metal support type cell (b) as a structural example of the conventional solid oxide fuel cell.

Explanation of symbols

1 Cell for Solid Oxide Fuel Cell 2 Porous Metal Substrate 3 Fuel Electrode Layer 4 Electrolyte Layer 5 Air Electrode Layer 6 Current Collection Layer 7 Porous Insulating Material
8 Insulating layer 9 Gas impermeable conductive material 10 Cell plate for solid oxide fuel cell

Claims (7)

A substrate-supporting cell in which a battery element having a laminated structure in which an electrolyte layer made of a solid oxide is sandwiched between a first electrode layer and a second electrode layer on a porous metal substrate,
A first electrode material is embedded on the upper surface side of the battery element forming portion in the porous substrate to form a first electrode layer, and a porous insulating material is embedded on the lower surface side,
A gas impermeable insulating material is embedded on the upper surface side of the porous substrate other than the battery element forming portion to form an insulating layer, and a gas impermeable conductive material is embedded on the lower surface side,
On the upper surface side of the porous substrate, an electrolyte layer is formed from the first electrode layer formed in the battery element forming portion to the surrounding insulating layer, and further the second layer formed on the electrolyte layer. A solid oxide fuel cell, characterized in that a current collecting layer made of a conductive material is formed in a mesh shape from the electrode layer to the insulating layer.   2. The solid oxidation according to claim 1, wherein the porous metal substrate and the gas-impermeable conductive material are made of a metal material containing at least one selected from the group consisting of Ni, Fe and Cr. Cell for fuel cell.   3. The solid oxide fuel cell according to claim 1, wherein the porous insulating material and the gas-impermeable insulating material are ceramic materials.   The gas impermeable insulating material is a mixture of alumina and / or zirconia and borosilicate glass, and the content of the borosilicate glass is 10% or less by mass ratio. The solid oxide fuel cell according to any one of the items.   5. A solid oxide fuel characterized in that a plurality of fuel cell cells according to any one of claims 1 to 4 are two-dimensionally connected and integrated in a direction substantially perpendicular to the stacking direction. Battery cell plate. A method for producing a fuel cell according to any one of claims 1 to 4 or a fuel cell plate according to claim 5,
[1] A step of filling a gas-impermeable conductive material on the lower surface side of a portion other than the battery element forming portion in the porous metal substrate,
[2] A step of filling a gas impermeable insulating material on the upper surface side of a portion other than the battery element forming portion,
[3] A step of filling a porous insulating material on the lower surface side of the battery element forming portion in the porous metal substrate,
[4] A step of temporarily firing a porous metal substrate filled with a gas-impermeable conductive material, a gas-impermeable insulating material, and a porous insulating material;
[5] A step of forming a first electrode layer on the upper surface side of the battery element forming portion,
[6] A step of forming an electrolyte layer on the upper surface side of the first electrode layer,
[7] A step of forming a second electrode layer on the upper surface of the electrolyte layer,
[8] A step of forming a current collecting layer in a mesh shape on the upper surface of the second electrode layer,
A process for producing a cell or a cell plate for a solid oxide fuel cell, comprising:   A method for producing a cell or a cell plate for a solid oxide fuel cell, wherein the first electrode layer, the electrolyte layer, the second electrode layer, and the current collecting layer are formed by a vacuum film formation method.

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