JP4658489B2 - Solid oxide fuel cell and substrate used therefor - Google Patents

Description

  The present invention relates to a solid oxide fuel cell (SOFC) using a solid electrolyte and a substrate used therefor.

  Conventionally, as a cell design of a solid oxide fuel cell, a flat plate type (stack type), a cylindrical type (tube type), and the like have been proposed.

  In the flat plate-type cell, a fuel electrode and an air electrode are respectively disposed on the front and back surfaces of a plate-like electrolyte, and a plurality of cells formed in this manner are used in a state where they are stacked via separators. The separator plays the role which completely isolate | separates the fuel gas and oxidant gas which are supplied to each cell, and the gas seal is given between each cell and the separator (for example, patent document 1). However, this flat cell has a drawback in that it is vulnerable to vibration, thermal cycle, etc. because it applies a gas seal by applying pressure to the cell. Yes.

  On the other hand, a cylindrical cell has a fuel electrode and an air electrode arranged on the outer peripheral surface and inner peripheral surface of a cylindrical electrolyte, and a cylindrical vertical stripe type, a cylindrical horizontal stripe type, and the like have been proposed (for example, Patent Documents). 2). However, the cylindrical cell has an advantage of excellent gas sealing properties, but has a disadvantage that the manufacturing process is complicated and the manufacturing cost is high because the structure is more complicated than that of the flat plate cell.

  In addition, there are the following problems. In order to improve the performance of both flat and cylindrical cells, it is necessary to reduce ohmic resistance by thinning the electrolyte. However, if the electrolyte is too thin, it is vulnerable to vibration and thermal cycling. There is a problem that the vibration resistance and durability are lowered.

  For this reason, as a fuel cell that replaces the flat plate type and the cylindrical type described above, the fuel electrode and the air electrode are arranged on the same surface of the substrate made of a solid electrolyte, and power is generated by supplying a mixed gas of fuel gas and oxidant gas. A non-diaphragm solid oxide fuel cell that can be used has been proposed (for example, Patent Document 3). According to this fuel cell, since it is not necessary to separate the fuel gas and the oxidant gas, the separator and the gas seal are not required, and the structure and the manufacturing process can be greatly simplified.

Further, in this non-membrane type solid oxide fuel cell, the conduction of oxygen ions occurs near the surface layer of the solid electrolyte, and the fuel electrode and the air electrode are formed close to each other on the same surface of the solid electrolyte. The thickness of the electrolyte does not directly affect the performance of the battery as in the case of the cylinder type. Therefore, the thickness of the electrolyte can be increased while maintaining the performance of the battery, thereby improving the vulnerability.
JP-A-5-3045 (first page, FIG. 6) Japanese Patent Laid-Open No. 5-94830 (first page, FIG. 1) JP-A-8-264195 (page 2-3, FIG. 1)

  However, the fuel cell of Patent Document 3 has the following problems. In this fuel cell, a plurality of electrode bodies composed of a pair of fuel electrodes and air electrodes are arranged on an electrolyte. And the fuel electrode and air electrode between adjacent electrode bodies are connected in series by the interconnector. However, in this structure, since an electrolyte exists between adjacent electrode bodies, this electrolyte can be a path for oxygen ions to move during power generation. Therefore, the electrolyte between the electrode bodies, and the fuel electrode and the air electrode sandwiching the electrolyte constitute a fuel cell to generate electric power. In this case, since the oxygen ions can move from the air electrode to the fuel electrode of the adjacent electrode body, the electromotive force may be reduced. Thereby, the original electromotive force of the single battery cell and the electromotive force of the battery formed between the electrode bodies are offset, and there is a problem that desired output characteristics cannot be obtained.

  On the other hand, it may be possible not to dispose the electrolyte between the adjacent electrode bodies, but in this case, it is necessary to divide the electrolyte or to prepare a plurality of single cells individually. Increase in cost, increase in cost, and decrease in yield rate. In addition, the battery performance is lowered and the degree of freedom in design is suppressed.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a solid oxide fuel cell capable of obtaining a high power generation output and a substrate used therefor.

The present invention has been made to solve the above problems, and includes an electrolyte and a plurality of electrode bodies each including a fuel electrode and an air electrode. The electrode body is disposed on one surface of the electrolyte, and both electrodes One of the electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval, and each of the electrode bodies is connected in series or in parallel by an interconnector, and at least one of the electrodes is connected to the electrolyte. Two through holes are formed, and at least a part of the interconnector is disposed on the other surface of the electrolyte, and the electrode body on one surface of the electrolyte and the interconnector on the other surface are electrically connected via the through hole. Connected.

According to this configuration, since one electrode in the electrode body is configured to surround the other electrode at a predetermined interval, in the electrode body adjacent on the electrolyte, the same poles are adjacent to each other. It becomes. Therefore, unlike the conventional example, it is possible to prevent the electromotive force from being canceled by the electrolyte existing between the adjacent electrode bodies. As a result, a high output can be obtained. Moreover, if one of the above-described structures is prepared as a base material, a fuel cell can be configured according to the intended use by appropriately wiring the interconnector. That is, since a plurality of electrode bodies are formed on the electrolyte, for example, when a high voltage is required, the electrode bodies may be connected in series, and when a high current is required, the electrode bodies are connected in parallel. do it. Therefore, for the series, or it is not necessary to prepare those individually for parallel, that Do and cost can be reduced.

  Furthermore, the following effects can also be obtained. Since each electrode body of the fuel cell is configured so that one electrode surrounds the other electrode at a predetermined interval, a current collector for taking out current is provided in a part of one electrode. The distance that the electrons move in the electrode, that is, the distance between the current collector and the position on the electrode farthest from the current collector is half the length of the electrode. Therefore, compared with the case where the current collector is provided at the end of the electrode as in the conventional example, the electron moving distance is shortened, and the loss during electron conduction can be reduced. As a result, high power generation efficiency can be obtained. In addition, there is an advantage that the size of the electrode body can be made compact compared to the strip-like and comb-like electrodes.

Further, in the fuel cell, at least one through hole is formed in the electrolyte, and at least a part of the interconnector is disposed on the other surface of the electrolyte, and the electrode body on one surface of the electrolyte and the interconnector on the other surface are connected. It is electrically connected through the through hole . By doing so, the number of interconnectors wired on one surface of the electrolyte is reduced, so that the wiring can be simplified and the degree of freedom in design can be increased. For example, since the proportion of the interconnector on one surface of the electrolyte can be reduced, the effective arrangement area of the electrodes can be increased, and as a result, the degree of integration of the electrodes can be improved. Furthermore, since the wiring of the interconnector is simplified, it is possible to prevent an increase in electrical resistance and disconnection due to the length of the wiring.

The present invention has been made to solve the above-described problem, and includes an electrolyte and a plurality of electrode bodies each including a fuel electrode and an air electrode, and each of the electrode bodies is disposed on one surface of the electrolyte. And one electrode of the two electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval, and each of the electrode bodies is a solid oxide connected in series or in parallel by an interconnector. The battery unit has two battery units having the same configuration as the physical fuel cell, and at least one through hole is formed in the electrolyte in each battery unit, and the other surfaces of the electrolyte in each battery unit are opposed to each other. The electrode bodies in each battery unit are electrically connected via the through holes.

  By configuring in this manner, the output can be increased by using two battery units, and the electrode bodies of the respective battery units can be connected through the through holes, so that the wiring can be simplified. At this time, it is preferable to dispose at least a part of the interconnector between the electrolytes of the battery units, and to electrically connect the interconnector and the electrode body through the through holes. By doing so, the interconnector disposed on one surface of the electrolyte can be simplified, and the degree of freedom of wiring can be improved.

The present invention has been made to solve the above-described problem, and includes an electrolyte and a plurality of electrode bodies each including a fuel electrode and an air electrode, and each of the electrode bodies is disposed on one surface of the electrolyte. One electrode of both electrodes is configured to surround the entire periphery of the other electrode with a predetermined interval, and each electrode body is connected in series or in parallel by an interconnector, A plurality of electrode bodies are further disposed on the other surface of the electrolyte, at least one through hole is formed in the electrolyte, and the electrode bodies disposed on one surface and the other surface of the electrolyte are the through holes. It is electrically connected via. Thereby, a high power generation output can be obtained while keeping the size of the battery compact.

  In the above fuel cell, the interconnector may include an intersecting section that intersects with the electrode body in a separated state. According to this configuration, a short circuit between the interconnector and the electrode body can be prevented. Therefore, the interconnector can be arranged not only on the surface of the electrolyte but also above the electrode body. Thereby, since the interconnector wired on the surface of the electrolyte can be reduced, the degree of freedom of wiring can be improved. Along with this, since a larger number of electrode bodies can be arranged on the electrolyte, a high power generation output can be obtained.

  As such wiring, the said crossing area can be comprised with an electroconductive wire. By using the wire as the interconnector wiring in this manner, a shape that is not in contact with the electrode body can be easily formed.

  Also, wiring can be performed as follows. That is, an insulating layer can be formed between the intersection section and the electrode body. By doing so, even if the interconnector and the electrode body cross each other, a short circuit can be surely prevented, and the effects as described above can be obtained. At this time, when the wire is used as an interconnector, the insulation is further improved, and an arrangement in which the wire is in contact with the insulating layer is possible, so that a shorter wiring is possible. Furthermore, there is an advantage that the wire is stably fixed.

  The electrode body is preferably configured such that one electrode is a fuel electrode and the other electrode is an air electrode, that is, the fuel electrode surrounds the air electrode. This is because the air electrode has low electron conductivity and is likely to cause ohmic loss. Therefore, the air electrode is surrounded by the fuel electrode, and the air electrode is made shorter than the fuel electrode to further reduce the loss during electron conduction. It is because it is thought that it can reduce.

  According to the solid oxide fuel cell of the present invention, a high output can be obtained.

(First embodiment)
Hereinafter, a first embodiment of a solid oxide fuel cell according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a fuel cell according to the present embodiment, and FIG. 2 is a partial side view of FIG.

  As shown in FIG. 1, the fuel cell includes an electrolyte 1 formed in a rectangular plate shape, and a plurality of electrode bodies E (24 in FIG. 1) disposed on one surface of the electrolyte 1. These electrode bodies E are connected by an interconnector 7.

  Each electrode body E includes a fuel electrode 3 and an air electrode 5, and a frame-shaped fuel electrode 3 is disposed around the rectangular air electrode 5 at a predetermined interval. The outer shape of the fuel electrode 3 is rectangular according to the air electrode 5. At this time, the distance between the fuel electrode 3 and the air electrode 5 is preferably, for example, 1 to 1000 μm, and more preferably 10 to 500 μm. Further, current collectors 31 and 51 for taking out current are formed on the fuel electrode 3 and the air electrode 5, respectively. The current collector 31 of the fuel electrode 3 and the current collector 51 of the air electrode 5 of the electrode body E adjacent thereto are connected by the interconnector 7, and the electrode bodies E are connected in series. In addition, it is preferable to set it as the space | interval between the adjacent electrode bodies E, for example, 10-5000 micrometers, and it is more preferable to set it as 1000-3000 micrometers.

  The interconnector 7 is formed as shown in FIG. As shown in the figure, an insulating layer 9 is formed on the fuel electrode 3, the air electrode 5 and the electrolyte 1 in the section (intersection section) between the current collectors 31 and 51 at both ends of each interconnector. An interconnector 7 is formed on the insulating layer 9. Thereby, the interconnector 7 is prevented from being short-circuited while passing over the fuel electrode 3.

Next, the material of the fuel cell configured as described above will be described. As the material of the electrolyte 1, those known as electrolytes for solid oxide fuel cells can be used. For example, ceria-based oxides such as (Ce, Sm) O ₃ , (Ce, Gd) O ₃ , ( Oxygen ion conductive ceramic materials such as La, Sr) (Ga, Mg) O _{3 and} other lanthanum galade oxides, scandium stabilized zirconia (ScSZ), yttria stabilized zirconia (YSZ) and other zirconia oxides Can be used. Since the electrolyte 1 is used as a substrate and needs a certain level of strength, the thickness is preferably, for example, 200 to 1000 μm.

  The fuel electrode 3 and the air electrode 5 can be formed of a ceramic powder material. The average particle size of the powder used at this time is preferably 10 nm to 100 μm, more preferably 50 nm to 50 μm, and particularly preferably 100 nm to 10 μm. In addition, an average particle diameter can be measured according to JISZ8901, for example.

As the ceramic powder material forming the fuel electrode 3, for example, a mixture of nickel and an oxygen ion conductive material can be used. The metal used at this time is not limited to nickel, and a metal that is stable in a reducing atmosphere of cobalt or a noble metal (such as platinum, ruthenium, or palladium) can be used. Examples of the oxygen ion conductive material include ceria-based oxides such as (Ce, Sm) O ₃ and (Ce, Gd) O _3, and lanthanum galades such as (La, Sr) (Ga, Mg) O _3. And oxygen ion conductive ceramic materials such as zirconia oxides such as scandium stabilized zirconia (ScSZ) and yttria stabilized zirconia (YSZ), and mixtures of such ceramic materials with nickel Preferably, the fuel electrode 5 is formed. Among these, it is particularly preferable to form the fuel electrode 5 with a cermet of nickel-ceria-based oxide. The mixed form of the oxygen ion conductive ceramic material and nickel may be a physical mixed form or a form of powder modification to nickel. Moreover, the ceramic material mentioned above can be used individually by 1 type or in mixture of 2 or more types.

As the ceramic powder material forming the air electrode 5, for example, a perovskite metal oxide can be used. Specifically, (Sm, Sr) CoO ₃ , (La, Sr) MnO ₃ , (La, Sr) CoO ₃ , (La, Sr) (Fe, Co) O ₃ , (La, Sr) (Fe, Co , Ni) O _{3 and the} like. These ceramic powders can be used alone or in a mixture of two or more.

The interconnector 7 and the current collectors 31 and 51 are made of Pt, Au, Ag, Ni, Cu, SUS, La (Cr, Mg) O ₃ , (La, Ca) CrO ₃ , (La, Sr) CrO. It can be formed of a lanthanum-chromite-based conductive ceramic material such as _3, and one of these may be used alone, or two or more may be used in combination.

  The fuel electrode 3 and the air electrode 5 are formed by adding the appropriate amount of varnish, organic solvent, etc. with the above-described materials as the main components. The film thicknesses of the fuel electrode 3 and the air electrode 5 are formed so as to be 1 μm to 500 μm after sintering, but preferably 10 μm to 100 μm. Further, the interconnector 7 and the current collectors 31 and 51 are also formed by adding the above additives to the above-described materials.

  Examples of the material constituting the insulating layer 9 include silicon oxide, aluminum oxide, and the like. However, other materials are electrically and ionically conductive and have an active fuel cell. There is no particular limitation as long as the material does not change near the operating temperature. One kind of the above-mentioned materials can be used alone, or two or more kinds of materials can be mixed and used.

Next, an example of a method for manufacturing the above-described fuel cell will be described. First, a plate-like electrolyte 1 made of the above-described material is prepared. Subsequently, the powder material for the fuel electrode 3 and the air electrode 5 described above is used as a main component, and an appropriate amount of varnish, photosensitive polymer, organic solvent, etc. is added to each of them and kneaded to prepare a fuel electrode paste and an air electrode paste. Create each one. The viscosity of each paste is preferably about 10 ³ to 10 ⁶ Pa · s so as to be compatible with the screen printing method described below. Similarly, the interconnector paste is prepared by adding an additive such as varnish to the above-described powder material. The viscosity of this paste is the same as that of the fuel electrode paste described above.

  Subsequently, the fuel electrode paste is applied to a plurality of positions on the electrolyte 1 as shown in FIG. 1 in the form of a rectangular frame by screen printing, and then dried and sintered at a predetermined time and temperature. Form. Next, as shown in FIG. 1, a rectangular air electrode paste is applied to each position surrounded by the fuel electrode 3 on each electrolyte 1 by screen printing, and dried and sintered at a predetermined time and temperature. Thus, the air electrode 5 is formed. In this way, 24 electrode bodies E are formed. And after forming the current collectors 31 and 51 on each fuel electrode 3 and the air electrode 5, the current collector 31 of each fuel electrode 3 and the current collector 51 of the air electrode 5 in the electrode body E adjacent thereto In the meantime, the insulating layer 9 is formed by a screen printing method. Thereafter, the interconnector paste is applied in a linear manner on each insulating layer 9 by screen printing to form the interconnector 1. Through the above steps, a fuel cell as shown in FIGS. 1 and 2 is completed.

  The fuel cell configured as described above generates power as follows. First, on one surface of the electrolyte 1 on which the electrode body E is arranged, a mixed gas of hydrogen or a fuel gas made of hydrocarbon such as methane or ethane and an oxidant gas such as air is in a high temperature state (for example, 400 to 1000 ° C). Thereby, oxygen ion conduction occurs near the surface layer of the electrolyte 1 between the fuel electrode 3 and the air electrode 5 in each electrode body E, and power generation is performed.

  As described above, in the fuel cell according to the present embodiment, the fuel electrode 3 in the electrode body E is configured to surround the air electrode 5 at a predetermined interval. In this case, the same poles are adjacent to each other. Therefore, unlike the conventional example, it is possible to prevent the electromotive force from being canceled by the electrolyte 1 existing between the adjacent electrode bodies E. As a result, high power generation output can be obtained.

  Incidentally, in the above description, the example in which the electrode bodies E are connected in series has been described, but it is needless to say that they can be connected in parallel. An example is shown in FIG. As shown in the figure, in this fuel cell, the current collector 31 of the fuel electrode 3 in each electrode body E is connected by an interconnector 71, and the current collector 51 of the air electrode 5 in each electrode body E is the other. The interconnector 72 is connected. Further, in order to prevent a short circuit between the interconnectors 71 and 72 and the electrodes 3 and 5, the insulating layer 9 described above is formed. In this way, if a substrate in which a plurality of electrode bodies E are arranged on the electrolyte 1 is prepared as a substrate, the electrode bodies E can be connected in series or in parallel only by changing the wiring of the interconnector 9. can do.

  In the above description, the insulating layer is formed so that the interconnector does not short-circuit with each electrode. However, the method for preventing the short-circuit is not limited to this, and various methods can be adopted. For example, as shown in FIG. 4, the cross section between the current collectors 31 and 51 is connected by a conductive wire 12 by wire bonding. Since the wire 12 passes above the electrodes 3 and 5, the wire 12 does not come into contact therewith and no short circuit occurs. Such a wire 12 can be formed of a metal material excellent in electronic conductivity, such as Pt, Au, Ag, Cu, Ni, and SUS. Moreover, in order to prevent a disconnection, it is preferable that the diameter is 0.3-1 mm.

  Moreover, the electrode body E can be formed not only on one surface of the electrolyte 1 but also on the other surface, and these can be connected by the interconnector 7 in the same manner as described above. By doing so, the power generation output can be increased while keeping the fuel cell compact.

(Second Embodiment)
Next, a second embodiment of the solid oxide fuel cell according to the present invention will be described with reference to the drawings. FIG. 5 is a plan view of the fuel cell according to the present embodiment, and FIG. 6 is a bottom view of FIG. FIG. 7 is a partial cross-sectional view of FIG.

  The difference between the fuel cell according to the present embodiment and the fuel cell according to the first embodiment is the wiring of the interconnector, and the configuration of the electrode body is the same as that according to the first embodiment, and thus the description thereof is omitted. To do. As shown in FIG. 5, in this fuel cell, 24 electrode bodies E are formed on one surface of a plate-like electrolyte 1 as in the first embodiment. As shown in FIG. 7, in the electrolyte 1, a through hole 11 is formed at a position in contact with each air electrode 5, and the current collector 52 is filled in the through hole 11. In addition, a current collector 32 similar to that of the first embodiment is formed on each fuel electrode 3.

  As shown in FIGS. 5 and 6, a first interconnector 73 is formed on one surface of the electrolyte 1 so as to connect the current collectors 32 of the fuel electrodes 3. On the other hand, a second interconnector 74 is formed on the other surface of the electrolyte 1 so as to connect the current collector 52 filled in the through hole 11. The electrode bodies E are connected in parallel by such interconnector wiring. Note that a first current collector 15 is provided on one surface of the electrolyte 1 to extract current from the end 73 of the first interconnector, and an end of the second interconnector 74 is disposed on the other surface of the electrolyte 1. A second current collector 16 is provided in the part. The current collectors 15 and 16 may be made of the same material as the interconnector.

  As described above, according to the present embodiment, the through hole 11 is formed in the electrolyte 1, a part of the interconnector is formed on the other surface of the electrolyte 1, and each electrode body E is connected through the through hole 11. is doing. Thus, by forming a part of the interconnector on the other surface of the electrolyte 1, the wiring on one surface of the electrolyte 1 can be simplified, and the degree of freedom in designing the wiring can be increased. In addition, since the proportion of the interconnector on one surface of the electrolyte 1 is reduced accordingly, the effective arrangement area of the electrode body E can be increased, and as a result, the degree of electrode integration can be improved. it can.

  In addition, in the said description, although the case where each electrode body was connected in parallel was demonstrated, it is applicable also when connecting in series. For example, a through hole is formed in each position corresponding to each fuel electrode 3 and air electrode 5 in the electrolyte 1, and the through hole is filled with a current collector. And the collector of each fuel electrode and the collector of the air electrode of the electrode body adjacent to this are connected by the interconnector formed in the other surface of electrolyte. Thereby, each electrode body can be connected in series.

  When the electrode body E is formed not only on one surface of the electrolyte 1 but also on the other surface, the electrode body on the one surface and the electrode body on the other surface can be connected using the through holes. By doing so, the power generation output can be increased while keeping the fuel cell compact.

(Third embodiment)
Hereinafter, a third embodiment of a solid oxide fuel cell according to the present invention will be described with reference to the drawings. FIG. 8 is a plan view of the fuel cell according to the present embodiment, and FIG. 9 is a bottom view of the battery unit shown in FIG. FIG. 10 is a partial cross-sectional view of FIG.

  In the present embodiment, the fuel cells connected in parallel described in the second embodiment are used as battery units, and two battery units are bonded to each other on the other surface of the electrolyte. In this case, as shown in FIG. 10, the positions of the through holes 11 in each electrolyte 1 are matched, and the current collector 53 is filled so as to penetrate both of the corresponding through holes 11 of both electrolytes 1. Yes. Further, the second interconnector 75 disposed on the other surface of each electrolyte 1 is made common so as to connect the current collector 53 filled in the through hole 11. That is, only one layer of the second interconnector 75 is formed so as to be sandwiched between the two electrolytes 1 and used as a common interconnector. Moreover, the 1st current collection parts 15 formed in the one surface of each electrolyte 1 are connected through the through-hole. Further, the second current collector 16 is connectable from one surface of any electrolyte 1 through a through hole.

  According to the above configuration, since the two battery units are bonded together, a high power generation output can be obtained while keeping the fuel cell compact. In addition, the interconnector wiring can be simplified, and a part of the interconnector can be shared, so that the cost can be reduced.

  Moreover, as shown in FIG. 11, a fuel cell can also be comprised by preparing two fuel cells shown in 1st Embodiment as a battery unit, and bonding the other surfaces of each electrolyte 1 together. In this case, it is also possible to form through holes 11 in each electrolyte 1 and connect the electrode bodies of the battery units via current collectors 53 filled in the through holes 11. At this time, since no interconnector is formed on the other surface of the electrolyte, the electrodes of both battery units can be connected by a wire or the like. For example, as shown in the figure, the fuel electrodes 3 of the battery units can be connected to each other by passing the wire 76 through the side surface of the electrolyte 1.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various change is possible unless it deviates from the meaning. For example, in the above-described embodiment, the screen printing method is used for applying each paste, but is not limited thereto, doctor blade method, spray coating method, lithography method, electrophoretic electrodeposition method, roll coating method, Other general printing methods such as a dispenser coating method, CVD, EVD, sputtering method, printing method such as transfer method, and the like can be used. Moreover, as a post-process after printing, a hydrostatic press, a hydraulic press, and other general press processes can be used.

  In the above embodiment, a plate-like electrolyte is used, but a base material may be disposed on the other surface of the electrolyte, and each electrolyte may be supported by this substrate. By doing so, even if the electrolyte 1 is thinned, the fuel cell can be prevented from becoming weak. The substrate used at this time can be made of, for example, a ceramic material such as alumina, silica, or titanium, or SUS. In addition, the electrolyte can be formed on the substrate after being thinned by printing.

  Further, in each of the above embodiments, the fuel electrode 3 and the air electrode 5 are formed in a rectangular shape, but the present invention is not limited to this, and the air electrode is formed so as to surround the fuel electrode at a predetermined interval. If it is, the shape is not particularly limited. For example, as shown in FIG. 12, each electrode can be formed in a circular shape (FIG. 12A) or in a polygonal shape (FIG. 12B).

  Further, in each of the above embodiments, the electrode body is configured so that the fuel electrode surrounds the air electrode. However, it is possible to reverse this, that is, the air electrode can surround the fuel electrode.

  Even if the current collector or interconnector is not formed or connected, the fuel cell of the present invention may be used and can be used. In that case, the fuel of the present invention If a current collector or interconnector is provided in a battery setting device, etc., and the fuel cell is set in the device, the current collector or interconnector is connected to the required location of each electrode. Good.

  Hereinafter, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited to a following example.

A commercially available plate-like electrolyte having a thickness of 1 mm was prepared as the electrolyte. This electrolyte is a ceria-based electrolyte, and its material is GDC [(Ce, Cd) O ₃ ] and gadolinium is doped. Further, the entire surface of the electrolyte was sandblasted so that the surface roughness Ra was 0.2 μm or less. As fuel electrode materials, nickel oxide (NiO) powder (particle size 0.01 to 10 μm, average particle size 1 μm) and SDC [(Ce, Sm) O ₃ ] powder (particle size 0.01 to 10 μm, average particle size) 0.1 μm) to a weight ratio of 7: 3, and then a cellulosic varnish was mixed to prepare a fuel electrode paste. The viscosity of the fuel electrode paste was 5 × 10 ⁵ mPa · s suitable for screen printing. Moreover, SSC [(Sm, Sr) CoO ₃ ] powder (0.1 to 10 μm, average particle size 3 μm) was used as an air electrode material, and a cellulosic varnish was mixed to prepare an air electrode paste. Similarly, the viscosity of the air electrode paste was set to 5 × 10 ⁵ mPa · s suitable for the screen printing method.

In addition, as an interconnector material for connecting the electrode bodies, Au powder (0.1 to 5 μm, average particle diameter 2.5 μm) is used, and a cellulose-based varnish is mixed therewith to form an interconnector paste. Produced. The viscosity of the interconnector paste was 5 × 10 ⁵ mPa · s suitable for screen printing. The current collector was formed in the same manner as the interconnector.

  Next, two fuel electrode pastes were applied on the electrolyte 1 by screen printing so as to be arranged at intervals of 1 mm. At this time, the fuel electrode paste was applied so as to form a rectangular frame having an outer side of 2700 μm and an inner side of 1950 μm. The coating thickness was 30 μm. And after drying at 130 degreeC for 15 minutes, it sintered at 1450 degreeC for 1 hour. Subsequently, an air electrode paste was applied on the same surface of the electrolyte 1 by a screen printing method. At this time, the air electrode paste was applied so as to form a rectangle with one side of 1550 μm, one inside the frame formed by each fuel electrode. And like the fuel electrode 3, after drying for 15 minutes at 130 degreeC, it sintered at 1200 degreeC for 1 hour.

Further, a paste containing Au as a main component was applied so as to overlap a part of each fuel electrode to obtain a current collector. Subsequently, sol-gel SiO ₂ containing R—Si (OC ₂ H ₅ ) ₃ (R: alkyl group) as a main component is printed at a position on the fuel electrode different from the current collector, and then dried at 150 ° C. An insulating layer was formed. Thereafter, an Au paste was applied so as not to protrude from the insulating layer, and an interconnector extending from the air electrode of one electrode body to the outside of the electrode body was formed. Further, it is made of a conductive paste such as Au so as to pass over the insulating layer formed on the fuel electrode of the other electrode body between the fuel electrode of one electrode body and the air electrode of the other electrode body. An interconnector was formed, and two electrode bodies were connected in series. After applying the Au paste, it was dried at 150 ° C. for 20 minutes and sintered at 900 ° C. for 2 hours. Thus, a fuel cell according to the example was obtained.

1 is a plan view of a first embodiment of a solid oxide fuel cell according to the present invention. It is a partial side view of FIG. FIG. 3 is a plan view showing another example of the solid oxide fuel cell according to FIG. 1. FIG. 3 is a plan view showing another example of the solid oxide fuel cell according to FIG. 1. It is a top view of 2nd Embodiment of the solid oxide fuel cell which concerns on this invention. FIG. 6 is a bottom view of FIG. 5. FIG. 6 is a partial cross-sectional view of FIG. 5. It is a top view of 3rd Embodiment of the solid oxide fuel cell which concerns on this invention. It is a bottom view of the battery unit of FIG. FIG. 9 is a partial cross-sectional view of FIG. 8. It is sectional drawing which shows the other example of the fuel cell which concerns on 3rd Embodiment. It is a top view which shows the other example of the electrode body which concerns on this invention.

Explanation of symbols

1 Electrolyte 3 Fuel electrode 5 Air electrode 7 Interconnector

Claims (11)

Electrolyte,
A plurality of electrode bodies comprising a fuel electrode and an air electrode;
Each of the electrode bodies is disposed on one surface of the electrolyte, and one electrode of both electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval ,
Each of the electrode bodies is connected in series or in parallel by an interconnector,
At least one through hole is formed in the electrolyte, and at least a part of the interconnector is disposed on the other surface of the electrolyte;
A solid oxide fuel cell in which an electrode body on one surface of the electrolyte and an interconnector on the other surface are electrically connected via the through hole. Electrolyte,
A plurality of electrode bodies comprising a fuel electrode and an air electrode;
Each of the electrode bodies is disposed on one surface of the electrolyte, and one electrode of both electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval ,
Each of the electrode bodies has two battery units having the same configuration as a solid oxide fuel cell connected in series or in parallel by an interconnector,
At least one through hole is formed in each electrolyte in each battery unit,
The electrolyte in each battery unit is disposed so that the other surfaces face each other, and the electrode body in each battery unit is electrically connected via the through hole. 3. The interconnector according to claim 2 , wherein at least a part of the interconnector is disposed between the electrolytes of the battery units, and the interconnector and the electrode body are electrically connected via the through hole. Solid oxide fuel cell. Electrolyte,
A plurality of electrode bodies comprising a fuel electrode and an air electrode;
Each of the electrode bodies is disposed on one surface of the electrolyte, and one electrode of both electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval ,
Each of the electrode bodies is connected in series or in parallel by an interconnector,
A plurality of the electrode bodies are further arranged on the other surface of the electrolyte,
A solid oxide fuel cell, wherein at least one through hole is formed in the electrolyte, and electrode bodies disposed on one surface and the other surface of the electrolyte are electrically connected through the through hole. 5. The solid oxide fuel cell according to claim 2 , wherein the interconnector includes an intersecting section that intersects with a part of the electrode body in a separated state. 6. The solid oxide fuel cell according to claim 5 , wherein the intersection section is formed of a conductive wire. The solid oxide fuel cell according to claim 5 or 6 , wherein an insulating layer is formed between the intersecting section and the electrode body. Electrolyte,
A plurality of electrode bodies comprising a fuel electrode and an air electrode;
Each of the electrode bodies is disposed on one surface of the electrolyte, and one electrode of both electrodes is configured to surround the entire periphery of the other electrode at a predetermined interval ,
Each of the electrode bodies is connected in series or in parallel by an interconnector,
The interconnector is a solid oxide fuel cell including an intersecting section that intersects with a part of the electrode body in a separated state . The solid oxide fuel cell according to claim 8 , wherein the intersecting section is composed of a conductive wire. The solid oxide fuel cell according to claim 8 or 9 , wherein an insulating layer is formed between the intersecting section and the electrode body. The solid oxide fuel cell according to any one of claims 1 to 10 , wherein the one electrode is a fuel electrode and the other electrode is an air electrode.

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