JP3126939B2 - Manufacturing method of laminated sintered body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solid electrolyte fuel cell, a steam electrolysis cell, an oxygen pump, a Knox decomposition cell, and other laminates for electrochemical cells and filters made of a plurality of different materials useful as filters. The present invention relates to a method for manufacturing a laminated sintered body having a ceramic layer.

[0002]

2. Description of the Related Art Ceramic filters have been used in various fields such as water treatment. As such a filter, for example, a filter in which a fine ceramic layer is formed on the surface of a main body made of a cylindrical porous ceramic is known.

[0003] Solid oxide fuel cells are roughly classified into so-called flat type and cylindrical type. In a plate-type solid oxide fuel cell, a so-called separator and a power generation layer are alternately stacked to form a power generation stack. In JP-A-5-54897, a fuel electrode and an air electrode are respectively formed to form a power generation layer, and an interconnector is formed. Ceramic powder and an organic binder are interposed between the power generation layer and the interconnector. A laminate is produced by sandwiching a thin film containing, and the laminate is heat-treated to join the power generation layer and the interconnector.

In Japanese Patent Application Laid-Open No. 6-88585, a green molded body of an interconnector and a green molded body of an air electrode side distributor are laminated, and the laminated body is integrally sintered to form an interconnector. Joining with a distributor is described. In this method, a stress relaxation layer for relaxing stress between the green molded bodies is formed between the two green molded bodies by applying a material having an extremely different heat shrinkage behavior from the two green molded bodies. This stress relieving layer is finely broken during shrinkage by firing, whereby the stress is relieved.

[0005]

A main part of a solid oxide fuel cell or a ceramics filter is made of a member obtained by laminating and sintering ceramics. But,
These had the following common problems. That is, in the case of a ceramic filter, in order to further improve the filtration efficiency, it is necessary to increase the size of the entire filter. In this case, the cost and the installation space are increased. Further, since the filter is made of bulk ceramics, there is a problem that the weight is large. In order to reduce the filtration resistance of the filter, it is necessary to reduce the thickness of the filter. However, in this case, there is a problem that the strength of the structure of the filter is significantly reduced.

[0006] In addition, the solid electrolyte fuel cell has a certain limitation in power generation performance due to poor gas supply to the electrodes, that is, high resistance to gas diffusion in the electrodes.
In addition, there is a problem that the unit cell is heavy and the material cost is high because a rare earth element is used.

An object of the present invention is to improve the function of holding each ceramic in a laminated sintered body of functional ceramics, such as a ceramic filter or a solid oxide fuel cell, and to reduce the weight of the laminated sintered body. In addition, it is intended to improve the structural strength of the laminated sintered body.

[0008]

The present invention provides a laminated sintered body comprising a plurality of ceramic layers made of a plurality of different materials, wherein each of the ceramic layers has
When manufacturing a laminated sintered body provided with a through-hole penetrating the laminated sintered body, by supplying each clay corresponding to each of the ceramic layers, simultaneously to a die, It is characterized in that a molded body of a laminated sintered body is manufactured, and the molded body is fired.

As a result, the function of holding the ceramics can be improved, the weight of the laminated sintered body can be reduced, and the structural strength of the laminated sintered body can be improved.

More specifically, when the laminated sintered body is a ceramic filter of a filter, the filtration resistance is reduced, the filtration efficiency is improved, and a large amount of liquid can be processed in a short time. Further, by providing the through-holes, it is possible to reduce the weight of the filter, and since the structure has independent through-holes in each ceramic layer, the structural strength can be kept high.

When the laminated sintered body is a laminated sintered body for an electrochemical cell and has a plate shape and includes an electrode layer and a separator layer, a through hole is formed in the electrode layer. By providing this, the gas diffusion efficiency inside the electrode is improved, and the electrode reaction is activated. As a result, in the case of a solid oxide fuel cell, the power generation output density is improved, and in the case of a steam electrolysis cell, the electrolysis efficiency is improved. Moreover, by providing the through holes in the separator, the cooling effect of the cell can be enhanced, and the temperature of the cell can be made uniform. In addition, these through holes can reduce the weight of the cell without impairing the strength of the structure.

[0012]

Hereinafter, more specific embodiments will be described. The laminated sintered body according to the present invention is preferably long. Specifically, the length of the laminated sintered body in the direction of the through hole is preferably at least twice the length in the direction perpendicular to the through hole, and more preferably at least five times.

In the present invention, a compact of the laminated sintered body is manufactured by simultaneously supplying the respective clays corresponding to the respective ceramic layers to the die, and the compact is integrally fired.

According to such a manufacturing method, a laminate having various cross-sectional shapes can be manufactured by changing the shape of the die. Also, particularly by utilizing extrusion methods, long products (eg, 1000 m long) can be used.
mm or more). Furthermore, according to this method, the number of manufacturing steps is extremely reduced.

By making the shape of the inlet of the die circular, processing for manufacturing the die becomes easy. The shape of the inlet of the die is appropriately changed so that the clay can easily enter. A plunger, a vacuum kneading machine, or the like can be used as an extruding mechanism for extruding each kneaded clay in the die.

When an aqueous binder is used as the clay,
Since it is not necessary to perform an exhaust treatment as in the case where an organic solvent is used, the facility can be simplified accordingly, and the molded body extruded from the base is hardly bent. In this case, the water content is more preferably set to 10 to 20% by weight. Further, as the aqueous binder, polyvinyl alcohol,
Methyl cellulose, ethyl cellulose and the like can be exemplified.

Further, it has been found that there is a problem that the molded body is easily bent when extruding the molded body. That is, the relatively hard kneaded clay tends to have a low flow rate at the time of extrusion, and the relatively soft kneaded clay tends to have a high flow rate at the time of extrusion. Because of this difference in flow velocity,
The phenomenon in which the molded body bends and deforms or warps from the die toward the tip of the molded body occurred. In addition, such a difference in the flow speed of the respective clays also caused a phenomenon that the position of the interface of each green molded body was shifted.

In order to prevent bending of the molded body, to extrude the molded body straight, and to prevent the position of the interface of each green molded body from shifting, the difference in hardness of each clay is set to 2 or less. Is preferred. The hardness here means
It is measured according to the standard of NGK clay hardness tester.

However, it is often difficult to finely adjust the hardness in an actual manufacturing apparatus and clay. Then, when continuously supplying each kneaded material into one die, the kneaded material constituting one green molded body is extruded from the first extrusion mechanism toward the die, and the second extrusion is performed. From the mechanism, the clay constituting the other green molded body can be extruded toward the die. This makes it possible to mechanically adjust the respective extrusion speeds and the respective extrusion pressures of the first extrusion mechanism and the second extrusion mechanism, thereby preventing the laminate from bending.

In the present invention, the liquid is supplied to the inner layer,
When the filtered liquid is discharged from the outer layer, examples of the material constituting the outer layer of the filter include silica, alumina, mullite, zirconia, spinel, silicon carbide, and cordierite. Preferably, the porosity is 10-70%. Examples of the material constituting the inner layer of the filter include silica, alumina, mullite, zirconia, spinel, silicon carbide, and cordierite, and the material of the inner layer and the material of the outer layer may be the same or different. Is also good.
The pore diameter of the inner layer is preferably 5 to 200 μm. In this case, the pore diameter of the inner layer is larger than that of the outer layer. The porosity of the inner layer is preferably 20 to 80%. Further, in the above, the configuration of the inner layer and the outer layer can be reversed, the liquid can be supplied to the outer layer, and the filtered liquid can be discharged from the inner layer.

As an electrochemical cell to which the present invention can be applied, there is an oxygen pump.

Further, the present invention can be applied to a high-temperature steam electrolysis cell. This cell can be used for a hydrogen production device and a steam removal device. In this case, the following reaction occurs at each electrode.

[0023]

Cathode: H ₂ O + 2e ⁻ → H ₂ + O ² −Anode: O ^{2 −} → 2e ⁻ + 1 / 2O ₂

Further, the present invention can be applied to a NOx decomposition cell. This decomposition cell can be used as a purification device for exhaust gas from automobiles and power generation devices. At present, NOx generated from a gasoline engine is handled by a three-way catalyst. However, when the number of fuel-efficient engines such as lean burn engines and diesel engines increases, the amount of oxygen in the exhaust gas of these engines is large, so that the three-way catalyst does not function.

Here, when the electrochemical cell of the present invention is used as a NOx decomposition cell, oxygen in exhaust gas is removed through a solid electrolyte membrane, and NOx is electrolyzed to be decomposed into N ₂ and O ^2- . Oxygen generated by this decomposition can also be removed. In addition, along with this process, steam in the exhaust gas is electrolyzed to generate hydrogen and oxygen, and this hydrogen is converted into NO.
the x is reduced to N _2.

In the electrochemical cell of the present invention, the electrodes to be integrated with the separator include both an anode such as an air electrode and a cathode such as a fuel electrode, and the anode is more preferable.
Moreover, it is particularly preferable to join the self-supporting (self-supporting) anode to the separator. This is because the self-supporting anode and separator are easier to handle because the thickness and strength of the self-supporting anode and separator are larger when forming a laminate of each green molded body of the anode and the separator.

The main raw material of the separator is preferably a perovskite-type composite oxide containing lanthanum,
More preferably, it is lanthanum chromite. This is because it has heat resistance, oxidation resistance, and reduction resistance. The clay constituting the green molded body of the separator can be produced by mixing an organic binder and water with the above-mentioned main raw material. Examples of the organic binder include polymethyl acrylate, nitrocellulose, polyvinyl alcohol, methyl cellulose, ethyl cellulose, starch, wax, acrylic acid polymer and methacrylic acid polymer. 100 weight of main raw material
The amount of the organic binder added is 0.5 to
It is preferably 5 parts by weight.

The main raw material of the anode is preferably a perovskite-type composite oxide containing lanthanum, more preferably lanthanum manganite or lanthanum cobaltite, and more preferably lanthanum manganite.
Lanthanum chromite and lanthanum manganite may be doped with strontium, calcium, chromium (for lanthanum manganite), cobalt, iron, nickel, aluminum and the like. Also, palladium, platinum, ruthenium, platinum-zirconia mixed powder, palladium-zirconia mixed powder, ruthenium-zirconia mixed powder, platinum-cerium oxide mixed powder, palladium-cerium oxide mixed powder, ruthenium-cerium oxide mixed powder Good.

The main raw materials of the cathode include nickel, palladium, platinum, nickel-zirconia mixed powder, platinum-zirconia mixed powder, palladium-zirconia mixed powder,
Nickel-cerium oxide mixed powder, platinum-cerium oxide mixed powder, palladium-cerium oxide mixed powder, ruthenium, ruthenium-zirconia mixed powder and the like are preferable.

As a material for the solid electrolyte membrane, yttria-stabilized zirconia or yttria-partially stabilized zirconia is preferable, but other materials can also be used.

In the case of a NOx decomposition cell, the solid electrolyte is particularly preferably cerium oxide-based ceramic, and the cathode material is preferably palladium or palladium-cerium oxide cermet.

The clay constituting the electrode compact can be produced by mixing an organic binder, a pore former and water with the main raw material of the electrode. Examples of the organic binder include those for the aforementioned separator. When the weight of the main raw material is 100 parts by weight, the amount of the organic binder to be added is preferably 0.5 to 5 parts by weight.

The degreasing step of the laminated molded article can be performed separately from the firing step, but it is preferable to perform degreasing of the laminated molded article in the course of increasing the temperature during the firing. In the case of a laminated molded article for a solid oxide fuel cell, the firing temperature is usually 1
300 ° C to 1700 ° C.

[Experimental Example 1] Hereinafter, an embodiment of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a ceramic filter 1, and FIG. 2 is a schematic partial cross-sectional view schematically showing a state where the filter of FIG. 1 is installed in a filtering device. By the following steps, FIG.
Were manufactured and the performance was evaluated.

(Preparation of Raw Materials) First, a clay was produced using alumina powder, cellulose and methylcellulose. 100 parts by weight of alumina raw material powder having an average particle size of 10 μm, 5 parts by weight of cellulose, 3 parts by weight of methylcellulose,
Mix 20 parts by weight of water, put this mixture in a kneader,
A kneaded product was prepared. This kneaded material is stored in a vacuum kneader,
A cylindrical clay body having a diameter of 50 mm and a length of 300 mm was manufactured. Separately, 3 parts by weight of methylcellulose and 23 parts by weight of water were mixed with 100 parts by weight of a raw powder of nalmina having an average particle size of 5 μm, and the mixture was put into a kneader to prepare a kneaded product.
The kneaded material was accommodated in a vacuum kneading machine to produce a cylindrical kneaded material having a diameter of 50 mm and a length of 300 mm.

(Molding Step) Next, a molded body of the filter was manufactured by simultaneous extrusion molding using the clay body A and the clay body B. In this case, an extruder having the form shown in FIG. 3 was used. That is, each passage 14 of each molding cylinder 13A, 13B
A and 14B were charged with clay body A 15A and clay body B 15B. The shaft 11A of the plunger 12A was moved, and the body 15A was extruded in the direction of the base 18. At the same time, the shaft 11B of the plunger 12B was moved, and the clay body B was pushed out to the base. The base 18 includes an inlet portion 18a and an outlet portion 18b. Inlet part 18a
, Two inlet passages 17A and 17B are formed, and a partition 16 is provided between the two. The cross section of each inlet passage is circular. Exit part 18b
The cross section of the middle outlet passage 19 is rectangular. A die 20 is provided at the tip of the base 18.

The respective extrusion speeds and pressures of the first plunger 12A and the second plunger 12B are adjusted so that the molded product does not bend. The molded body thus obtained has a cross-sectional shape corresponding to the shape of FIG.

(Firing Step) Next, the molded body was placed in a thermo-hygrostat and dried. Next, the compact was placed in an electric furnace and heated to 1500 ° C. at a rate of 200 ° C./hour.
The temperature was maintained at 1500 ° C. for 3 hours, and then allowed to cool to room temperature to obtain a cylindrical laminated sintered body 1 shown in FIG. A predetermined number of through holes 4 are formed in the outer layer 2 of the laminated sintered body 1, and a predetermined number of through holes 5 are also formed in the inner layer 3. In the central portion of the inner layer 3, a through hole 6 having a size larger than the other through holes 4, 5 is formed. The inner layer 3
The outer layer 2 is formed by the kneaded material 15A, and the outer layer 2 is formed by the kneaded material 15B.

The dimensions of the outer cross section shown in FIG.
The dimensions of the through holes 6 are 3 mm × 3 mm, the dimensions of the through holes 4 and 5 are 1 mm × 1 mm, and the length of the laminated sintered body is 300 mm. Samples of 10 mm × 10 mm × 1 mm were cut out from the outer layer 2 and the inner layer 3, respectively, and the porosity of each sample was measured. The porosity of the sample cut from the inner layer 3 was 45%, and the porosity of the sample cut from the outer layer 2 was 35%. The pore size of the outer layer 2 is smaller than the pore size of the inner layer 3 so that finer particles can be removed. A sample having a length of 50 mm was cut out from the laminated sintered body to obtain a filter.

As shown in FIG. 2, flanges 7 were attached to both ends of the filter 1, the space between them was sealed water-tight by a seal member 51, and this was attached to a predetermined position in the case 8. Using this filtration device, a test of filtration performance was performed. Specifically, an alumina powder having an average particle diameter of 1 μm was dissolved in water to obtain a slurry, and the slurry was allowed to flow into the through holes 6 and 5 from the inlet passage 9A as shown by the arrow A. Aspirated from the outside of Filter 1. Part of liquid is outlet 9B
Flows out of the filter as shown by an arrow B, and a part thereof passes through the filter as shown by arrows C and D and flows into the filtration chamber 10. Table 1
The amount of water filtered at each time shown in was measured, and the measurement results are shown in Table 1.

However, when the filter is actually used, the filter is clogged when it is filtered to some extent, so that the clogging can sometimes be removed.
In this embodiment, without removing such clogging,
Data obtained. In order to remove the clogging, reverse washing is performed, or only the washing water is allowed to flow into the through holes 6 and 5 from the inlet passage 9A without sucking the outside of the filter 1, thereby causing the clogging. Can be discharged from the outlet 9B.

As a comparative example, a filter 23 shown in FIG. 4 was manufactured, and the amount of filtered water was measured as described above. However, in FIG. 4, the filter 23 includes an outer layer 24 and an inner layer 25, and a through hole 53 is provided in the inner layer 25. However, the kneaded clay constituting the inner layer and the outer layer is the same as in the above-described embodiment, and each kneaded body A, B
A molded body was obtained by molding into the form shown in FIG. 4, and the molded body was placed in an electric furnace and heated at a rate of 200 ° C.
The temperature was raised to 1500 ° C./hour, kept at 1500 ° C. for 3 hours, and then allowed to cool to room temperature to obtain a laminated sintered body.

The size of the inner layer of the laminated sintered body is 15 mm
× 15 mm × 300 mm, the cross-sectional dimension of the outer layer 24 is 30 mm × 30 mm, and the dimension of the through hole 53 is 3 m
m × 3 mm. The porosity of this laminated sintered body was 35%. From this laminated sintered body, a filter having a length of 50 mm was cut out.

[0044]

[Table 1]

As can be seen from Table 1, according to the present invention,
The amount of filtered water could be significantly improved without impairing the function as a filter.

Next, an embodiment in which the present invention is applied to an electrochemical cell will be described. FIG. 5A is a front view schematically showing a laminated sintered body 32 for an electrochemical cell according to the present invention, and FIG. 5B is a front view showing a cell 31A.
The laminated sintered body 32 includes an anode layer 27 and a separator 28. A predetermined number of through holes 29A are formed in the anode layer 27, and the through holes 30A are similarly formed in the separator 28.
Are formed. 74 is a boundary between the anode layer and the separator.

In the laminated sintered body 32, a solid electrolyte film 56 is formed so as to cover at least the surface 27a of the porous anode layer 27, and the cathode film 3 is formed on the solid electrolyte film 56.
Form 3 In the present embodiment, the solid electrolyte membrane 56
Is in contact with the upper end of the separator 28, so that one gas (eg, oxidizing gas) in the through holes 29A, 30A is changed to the other gas (eg, fuel gas) flowing outside the cell 1A. Avoid direct contact.

An extruder as shown in FIG. 3 can be used for molding the laminated sintered body of FIG. 5 (a).

FIG. 6 is a front view schematically showing an electrochemical cell 31B according to still another embodiment. The laminated sintered body 60 includes the anode layer 34 and the separator 35. A predetermined number of through holes 29B are formed in the anode layer 34. Here, when viewed in the direction of the cross section, there are four rows of through holes 29B.
They are arranged in two rows. Similarly, through holes 30B are formed in the separator 35, and the through holes 30B are arranged in 4 rows × 2 rows as viewed in the direction of the cross section.

FIGS. 7 and 8 are front views schematically showing electrochemical cells 58 and 62 according to still another embodiment, respectively. In the cell 58 shown in FIG. 7, the laminated sintered body 71 includes an anode layer 59 and a separator 70. A predetermined number of through holes 29D are formed in the anode layer 59. Similarly, a through-hole 30 </ b> D is formed in the separator 70. Here, for example, three through holes 61 are provided along the boundary 74 between the anode layer 59 and the separator 70, and each through hole 61 faces both the anode layer 59 and the separator 70.

As described above, in the present invention, a through hole can be provided along the boundary between the separator and the anode layer. By flowing an oxidizing gas such as air into the through holes, the power generation efficiency of the anode layer can be improved.

The solid electrolyte film 56 is formed so as to cover at least the surface 59 a of the porous anode layer 59 of the laminated sintered body 71, and the cathode film 33 is formed on the solid electrolyte film 56.

In the unit cell 62 shown in FIG. 8, the laminated sintered body 72 includes the anode layer 62 and the separator 63.
A predetermined number of through holes 29E are formed in the anode layer 62. Similarly, a through hole 30E is formed in the separator 63. The solid electrolyte membrane 56 is formed so as to cover at least the surface 62 a of the porous anode layer 62 of the laminated sintered body 72, and the cathode membrane 33 is formed on the solid electrolyte membrane 56.

In this embodiment, in the laminated sintered body 72, the anode layer 62 is made thicker than the separator 63,
A large number of through holes 29E were provided in the anode layer 62. Generally, in an electrochemical cell, the resistance of the separator is higher than the resistance of the anode. Therefore, by making the anode layer thicker than the separator and making the separator having a higher resistance value thinner, the overall resistance value of the laminated sintered body 72 could be minimized.

FIG. 9A is a front view schematically showing a laminated sintered body 36 according to still another embodiment, and FIG.
FIG. 9 is a front view showing an electrochemical cell 31C using the laminated sintered body 36, and FIG. 9C is a cross-sectional view when the cell 31C is cut along its length direction.

The laminated sintered body 36 includes an anode layer 37 and a separator 38. A predetermined number of through holes 29C are formed in the anode layer 37, and through holes 30C are also formed in the separator 38. The solid electrolyte film 56 is formed so as to cover the side surface 37 a of the anode layer 37 and to cover the upper portion of the side surface 38 a of the laminated sintered body 38.
A cathode film 33 is formed on 6 to form a cell 31C. Here, as shown in FIG. 9C, the end of the through hole 30C in the separator communicates with the end of the through hole 29C in the anode layer 37, and the length of the anode layer 37 is 38 is smaller than the length. Solid electrolyte membrane 56
Covers the entire side surface 37b on the terminal side in the longitudinal direction of the anode layer 37 and covers the upper end of the side surface 38b on the terminal side in the longitudinal direction of the separator 38.

In the case of a solid oxide fuel cell, during power generation, as shown by the arrow E, the through hole 30C
Supply oxidizing gas into the interior. The oxidizing gas collides with the end wall surface of the separator and changes direction, enters the through hole 29C in the air electrode layer 37, and is discharged as shown by an arrow F.

Hereinafter, more specific experimental results will be described. [Experimental Example 2] A unit cell of a solid oxide fuel cell as shown in FIG. 5 (b) and a unit cell of a comparative example were manufactured, and a power generation test was performed on each unit cell.

(Production of Clay for Air Electrode Layer and Separator) Lanthanum manganite raw material powder 1 having an average particle size of 4 μm
100 parts by weight, 10 parts by weight of cellulose, 3 parts by weight of methylcellulose, and 18 parts by weight of water were put into a kneader to prepare a clay. Using this kneaded material, a diameter 5 mm
Clay for the air electrode layer having a length of 0 mm and a length of 300 mm was produced.

On the other hand, 100 parts by weight of lanthanum chromite raw material powder having an average particle diameter of 3 μm, 3 parts by weight of methylcellulose,
12 parts by weight of water was put into a kneader to prepare a kneaded material for a separator. Using a vacuum kneader, diameter 50 mm, length 300
mm was manufactured.

(Simultaneous Extrusion Molding and Firing) A molded article having the form shown in FIG. 5A was produced using an extrusion molding apparatus as shown in FIG. While adjusting the speed of each plunger, the piston was simultaneously advanced and extruded. The molded body thus obtained was placed in a thermo-hygrostat and dried. Next, the compact was placed in an electric furnace and heated to 1550 ° C. at a rate of 200 ° C./hour.
For 4 hours and then allowed to cool to room temperature. The size of the fired body was 24 mm × 8 mm × 300 mm, and the size of the through hole was a rectangle of 3 mm × 4 mm.

A sample of 10 mm × 10 mm × 1 mm was cut out from the air electrode layer and the separator of the fired body, and the porosity was measured. As a result, the porosity of the air electrode layer was 35%, and the porosity of the separator was 0.3%.

On the other hand, a laminated sintered body of a comparative example was manufactured in the same manner as in the above-described example. However, no through-hole was provided on the separator side.

A sample having a size of 24 mm × 8 mm × 50 mm was cut out from each of the fired bodies of the above-mentioned Examples and Comparative Examples, and 8 mol of yttria-stabilized zirconia (lanthanum manganite) was cut using a plasma spraying machine. (Solid electrolyte) film was formed (film having a thickness of 100 μm). A nickel-zirconia cermet was formed thereon by a screen printing method. The assembly thus obtained is
This was placed in an electric furnace and heat-treated at 1400 ° C. to obtain each unit cell of the examples and comparative examples of the present invention.

(Power generation test of solid oxide fuel cell) FIG.
A power generation test was performed using a power generation test apparatus schematically shown in FIG. Each cell 40 of the example and the comparative example was installed between current collectors 47 and 41, and each current collector was connected to platinum wires 42 and 43. These were accommodated in the container 45. Hydrogen was humidified by passing hydrogen through a room temperature bubbler, supplied into the container as shown by arrow G, brought into contact with the fuel electrode of the unit cell, and discharged from the container as shown by arrow H.

The cell 40 was air-tightly fixed to a ceramic manifold 44. Air was supplied through the manifold 44 as shown by the arrow I, and the air was flown into the through holes 29A and 30A, and was discharged as shown by the arrow J.
At this time, in the unit cell 31A of the embodiment of the present invention, the air supplied into the through hole 30A of the separator escapes to the outside of the unit cell while depriving the heat generated by the power generation to cool the unit cell. There is. As a result, an operational effect of uniforming the temperature distribution in the longitudinal direction of the cell was obtained.

It is known that lanthanum chromite used for the separator has a higher resistance in a reducing atmosphere such as hydrogen than in air. However, by providing a through hole in the separator and supplying air into the through hole, the resistance of the separator is reduced,
The operation and effect that the resistance of the cell itself can be reduced was obtained.

In this power generation test, since only the unit cells were tested, the heat of the air passing through the through holes in the separator was not used. However, in a practical generator, a number of cells are connected in series. Therefore, air is mixed with excess fuel gas and burned, and the heat of combustion is
It can be used for heating and hot water supply of the reformer. The current collector used a nickel plate.

Further, the unit cell of the comparative example was tested as described above. Using the cells of the examples and comparative examples of the present invention, the maximum output of the cells was measured under the power generation condition at a temperature of 1000 ° C., and the output density per unit weight is shown in Table 2. From this result, if the cells occupy the same volume,
In the case of the embodiment of the present invention in which the separator has through holes, it can be seen that the output density per unit weight is high.

[0070]

[Table 2]

[Experimental Example 3] A unit cell as shown in FIGS. 9A to 9C was manufactured, and a power generation experiment was performed. This unit cell was manufactured in the same manner as the unit cell 31A shown in FIG. 5B. The unit cell 31C was installed in a power generator, and a power generation experiment was performed.

FIG. 12 is a schematic diagram showing an outline of this power generation device. The positive electrode current collector plate 6 is placed in the container 64 of the power generator.
6, two unit cells 31C and a negative electrode current collector 67 were sequentially installed. Between the positive electrode current collector 66 and the cell 31C, between adjacent cells, and between the cell 31C and the negative electrode current collector 67.
, Electrical connection was made by filling a nickel felt 68, respectively. A fuel gas supply port 64a was provided at one end of the container, and a combustion gas discharge port 64b was provided at the opposite end. The oxidizing gas supply pipe 65 was attached to the discharge port 64b side, and the tip of the supply pipe 65 was attached to the end of the cell 31C in an airtight manner.

Hydrogen is humidified by passing hydrogen through the room temperature bubbler, and hydrogen is supplied into the container 64 as shown by the arrow K, and between the unit cells 31C adjacent to each other, as shown by the arrow L, between the unit cell and each current collector plate 66, 67. On the other hand, as shown by the arrow N, air is supplied into the supply pipe 65, flows into the through hole 30C on the separator 38 side as shown by the arrow E, further flows into the through hole 29C of the air electrode layer 37, and the arrow F Was discharged from the cell as shown in FIG. The used air and hydrogen were reacted in the combustion space 77, and the combustion exhaust gas was discharged from the discharge port 64b as shown by the arrow M.

As a result of this power generation test, 0.17 W / (cm
A power density per unit weight of ² · g) was obtained. In addition, the unit cells were cooled while the air passed through the separator, and the air was preheated. As a result, the entire temperature distribution of the unit cells became uniform.

[Experimental Example 4] An experimental example in which the present invention is applied to a steam electrolysis cell will be described. A steam electrolysis cell of the example shown in FIG. 5B and a steam electrolysis cell of the comparative example were manufactured, and the amount of hydrogen generated per unit weight of the cell was measured for each cell.

In the same manner as in Experimental Example 2, a laminate formed of the anode and the separator was produced. This molded body was dried and fired in the same manner as in Experimental Example 2. From the anode layer and the separator of the obtained fired body, 10 mm × 10 mm × 1
mm sample was cut out and the porosity was measured. As a result,
The porosity of the anode layer was 35%, and the porosity of the separator was 0.3%.

On the other hand, a laminated sintered body of a comparative example was manufactured in the same manner as in the above-described example. However, no through-hole was provided on the separator side.

A sample having a size of 24 mm × 8 mm × 50 mm was cut out from each of the fired bodies of the above Examples and Comparative Examples of the present invention, and 8 mol of yttria-stabilized zirconia (lanthanum manganite) was cut using a plasma spraying machine. (Solid electrolyte) film was formed (film having a thickness of 100 μm). A platinum paste was printed thereon. The assembly thus obtained was placed in an electric furnace and heat-treated at 1400 ° C. to obtain each of the steam electrolysis cells of Examples and Comparative Examples of the present invention.
The area of each cathode was 8 cm ² .

Each of the steam electrolysis cells of the example and the comparative example was installed in the test apparatus schematically shown in FIGS. 10 and 11, and an electrolysis test was performed. Helium gas containing 10% water vapor was supplied to the cathode side at 500 cc / min. Air was supplied to the anode side at a rate of 200 cc / min.

At 1000 ° C., steam electrolysis was performed at a current density of 0.3 A / cm ² . On the exhaust side of helium gas containing water vapor, by gas chromatography,
The amount of hydrogen generated was measured, and the amount of hydrogen generated per unit weight of the cell was calculated. As a result, in the steam electrolysis cell of the embodiment of the present invention, 0.63 cc · min ⁻¹ g
⁻¹ in the steam electrolysis cell of the comparative example.
It was 39 cc min ^-1 g ^-1 . Thus, it has been found that by applying the present invention to a steam electrolysis cell, the amount of hydrogen generated per unit weight is increased, and the weight of the cell can be reduced.

[0081]

As described above, according to the present invention, in a laminated sintered body of functional ceramics, such as a ceramics filter or an electrochemical cell, the function of holding each ceramic is improved and the laminated ceramics are sintered. It is possible to reduce the weight of the sintered body and to improve the structural strength of the laminated sintered body.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a ceramic filter 1. FIG.

FIG. 2 is a schematic partial cross-sectional view schematically showing a state where the filter of FIG. 1 is installed in a filtration device.

FIG. 3 is a schematic diagram showing a state in which a multilayer molded body is extruded by simultaneously supplying the clay 15A and the clay 15B into one extrusion molding die 18;

FIG. 4 is a front view schematically showing a filter of a comparative example.

FIG. 5 (a) is a front view schematically showing a laminated sintered body 32 for an electrochemical cell according to another embodiment of the present invention, and FIG. 5 (b) is a front view showing a cell 31A. It is.

FIG. 6 is a front view schematically showing an electrochemical cell 31B according to still another embodiment of the present invention.

FIG. 7 is a front view schematically showing an electrochemical cell 58 according to still another embodiment of the present invention.

FIG. 8 is a front view schematically showing an electrochemical cell 62 according to still another embodiment of the present invention.

FIG. 9 (a) is a front view showing a laminated sintered body 36 for an electrochemical cell according to still another embodiment of the present invention,
(B) is a front view showing the cell 31C, (c) is
It is sectional drawing of cell 31C.

FIG. 10 is a diagram schematically showing a power generation test device or an electrolytic test device used in an example of the present invention.

11 is an enlarged view showing a periphery of an electrochemical cell in the test apparatus of FIG.

FIG. 12 is a schematic diagram showing an outline of a power generation test apparatus used for testing the power generation characteristics of the unit cells of FIGS. 9 (a) to 9 (c).

[Explanation of symbols]

Reference Signs List 1 laminated sintered body for filter 2 outer layer 3
Inner layer 4, 5 Filter through hole 8 Case 11
A, 11B Plunger 13A, 13B Molding cylinder 14A, 14B Path of molding cylinder 15A, 15B
Clay 18 Die 20 Dice 27, 3
4, 37, 59, 62 anode layer (air electrode layer) 28,
35, 38, 63, 70 Separator 29A, 29
B, 29C, 29D, 29E Through holes in anode layer (air electrode layer) 30A, 30B, 30C, 30D, 30E Through holes in separators 31A, 31B, 31C, 58,
62 electrochemical cells (unit cells) 32, 36, 60,
71, 72 Laminated sintered body for electrochemical cell, 33 Cathode film (fuel electrode film) 51 Seal member 56 Solid electrolyte membrane

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification code FI // B01D 71/02 C25B 9/00 (JP, A) JP-A-8-180889 (JP, A) JP-A-6-287650 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 18/00 B28B 3 / 26 C25B 9/00 H01M 8/02 B01D 71/02

Claims (11)

(57) [Claims] 1. A laminated sintered body comprising a plurality of ceramic layers made of a plurality of different materials, wherein a through hole is provided in each of the ceramic layers, each penetrating the laminated sintered body. To manufacture laminated sintered bodies
In doing so, each clay corresponding to each of the ceramic layers described above,
By simultaneously supplying to the die,
It specializes in manufacturing a compact of compacted body and firing this compact.
A method of manufacturing a laminated sintered body. 2. A method for extruding each of the clay in the die.
2. An extrusion mechanism is provided.
the method of. 3. One of said bases by a first extrusion mechanism.
And extruding the kneaded clay by a second extrusion mechanism.
Extruding the other said clay in gold
Item 7. The method according to Item 1. 4. The method according to claim 1, wherein the pushing mechanism is a plunger or a vacuum soil.
The kneading machine according to claim 2 or 3, wherein the kneading machine is a kneading machine.
Method. 5. The kneaded material contains an aqueous binder.
In any one of claims 1-4, characterized in that
The described method. 6. The water content of the clay is 10 to 20% by weight.
The contract according to any one of claims 1 to 5, wherein
The method according to claim. 7. The difference in hardness between the respective clays is 2 or less.
The method according to any one of claims 1 to 6, wherein
The described method. 8. The ceramic sintered body for a filter as claimed in claim 8, wherein
The filter according to any one of claims 1 to 7, wherein the filter is a filter.
A method according to any one of the preceding claims. 9. The laminated sintered body according to claim 1, wherein said laminated sintered body is a laminated body for an electrochemical cell.
Sintered, plate-shaped, electrode layer and separator
9. The method according to claim 1, further comprising the steps of:
A method according to any one of the preceding claims. 10. Filling clay for forming said separator.
Is a perovskite-type composite oxide containing lanthanum
An organic binder characterized by containing an organic binder and water.
The method of claim 9. 11. The clay for forming said electrode layer is a laminating material.
Perobu Sukaito type complex oxide containing lanthanum, organic Bas
It is characterized by containing indder, pore former and water
10. The method of claim 9, wherein