JP2001273914A - Electrochemical device and accumulated electrochemical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease a diffusion resistance of each gas flowing toward each electrode in each electrochemical cell, and also to control deterioration of material for connecting parts of the electrochemical cells next to each other in an electrochemical device which has a structure consisted of plural electrochemical cells connected electrically to each other. SOLUTION: The electrochemical device 5 is equipped with a solid electrolyte layer 9, and with a plurality of first electrodes 16 and a plurality of second electrodes 17 both installed at the solid electrolyte layer 9. A plurality of electrochemical cells 15 are composed of the first electrodes 16 and the second electrodes 17. It is also equipped with at least one through hole electric conductor 22 that penetrates the solid electrolyte layer. At least two electrochemical cells 15, which are next to each other on the solid electrolyte layer, are electrically connected via the through hole electric conductor 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated electrochemical device having a plurality of electrochemical cells.

[0002]

2. Description of the Related Art "Fuel cell power generation" (edited by the Institute of Electrical Engineers of Japan, Special Committee on Fuel Cell Drivability Investigation) Corona, page 77,
It is described that a plurality of solid oxide fuel cells are formed on a porous substrate. That is, each cell is formed by sequentially forming a fine air electrode, a solid electrolyte membrane, and a fuel electrode on the surface of the porous substrate. At this time, a number of unit cells are formed on the porous substrate. Then, an interconnector film is formed between the fuel electrode and the air electrode of the adjacent unit cells, respectively, and the adjacent unit cells are electrically connected in series.
Then, the oxidizing gas permeates the porous substrate and diffuses in the air electrode in contact with the porous substrate. On the other hand, the fuel gas passes through the fuel electrode and contributes to power generation.

[0003]

SUMMARY OF THE INVENTION
A large number of power generation elements can be integrated in a small volume to improve the power generation amount per unit space, and thus have been recognized as an excellent design concept.

[0004] However, when the present inventor further studies, there are actually the following difficult problems. That is, for example, the oxidizing gas needs to pass through the porous substrate once, and thereafter diffuse in the air electrode in contact with the porous substrate. However, the porous substrate is a portion that maintains the overall structural strength of the assembled battery, and therefore requires a certain degree of thickness and denseness. However, when the porous substrate is thickened or the porosity is reduced, the oxidizing gas hardly permeates through the porous substrate, so that it is difficult for the oxidizing gas to diffuse into the air electrode in contact with the porous substrate, and the utilization efficiency is reduced. Becomes lower.

Further, adjacent electrochemical cells must be connected by an interconnector film formed on a porous substrate. Therefore, the interconnector is exposed not only to the fuel gas but also to the oxidizing gas diffusing through the porous substrate. The temperature at the time of this exposure is, for example, 1000 ° C. For this reason, the material of the interconnector must have three conditions: high conductivity, stability to oxidizing gas at high temperature, and stability to fuel gas at high temperature. unknown. As a result, the resistance associated with the connection between the adjacent cells increases, or when operated for a long period of time, the connection resistance between the cells increases due to the deterioration of the material of the interconnector.

An object of the present invention is to reduce the diffusion resistance of each gas up to each electrode of each electrochemical cell in an electrochemical device having a structure in which a plurality of electrochemical cells are electrically connected. And the deterioration of the material of the connection part of the adjacent electrochemical cell can be suppressed.

[0007]

The present invention comprises a solid electrolyte layer, a plurality of first electrodes provided on the solid electrolyte layer, and a plurality of second electrodes provided on the solid electrolyte layer. An electrochemical device in which a plurality of electrochemical cells are configured by the first electrode and the second electrode,
At least one through-hole conductor penetrating the solid electrolyte layer is provided, and at least two adjacent electrochemical cells are electrically connected via the through-hole conductor.

Hereinafter, the present invention will be described with reference to the drawings as appropriate.

FIG. 1A is a cross-sectional view showing an electrochemical device 5 according to one embodiment of the present invention, and FIG.
FIG. 3A is a plan view of the device 5 as viewed from a first electrode 16 side.

The apparatus 5 of FIG. 1 is provided with a plurality of, for example, four, electrochemical cells 15, each of which is connected in series. That is, in this example, the solid electrolyte layer 9 has a rectangular flat plate shape in plan view. For example, four first electrodes 16 are formed on one surface 9c of the solid electrolyte layer 9, and the second electrode 1 is formed on the other surface 9d.
7 are formed, for example. Each first electrode 16
Each corresponding second electrode 17 and electrochemical cell 15 are configured. B is the main working area of the electrochemical device 5.

An elongated gap 23 is formed between adjacent first electrodes 16 to insulate between adjacent electrodes 16. An elongated gap 24 is formed between the adjacent second electrodes 17 to insulate between the electrodes 17 of the adjacent cells. An end of each electrode 16 is opposed to an end of an electrode 17 of an adjacent cell with the solid electrolyte layer 9 interposed therebetween. In the solid electrolyte layer 9, a through-hole conductor 22 is provided in a region facing the above-mentioned end portion. The electrodes 16 and 17 of the adjacent electrochemical cell 15 are connected in series by each through-hole conductor 22.

According to such an electrochemical device, in a device in which a plurality of electrochemical cells are provided on one substrate, the diffusion resistance of each gas up to each electrode of each electrochemical cell can be reduced. This is because the solid electrolyte layer itself is used as a substrate for supporting the whole, and a separate porous substrate is not required. Further, since the side peripheral surface of the through-hole conductor 22 is covered with the solid electrolyte layer 9 and is not exposed to the oxidizing gas or the fuel gas, the material of the through-hole conductor is hardly deteriorated. Of course, only the upper end face and the lower end face in FIG. 1 of the through-hole conductor 22 come into contact with the external gas diffused through the electrodes 16 and 17. However, since this is a gas after being diffused and transmitted through the electrode, the concentration of oxygen and fuel in the gas is low and the absolute amount of the gas is also small, so that the degree of deterioration of the through-hole conductor is small.

In the example shown in FIG. 1, adjacent cells 15 are connected in series. Thus, by connecting a plurality of electrochemical cells in series in one solid electrolyte layer, for example, the extraction voltage can be increased, and the current value can be reduced accordingly. As the current value decreases, the current loss inside the device can be reduced accordingly.

In a particularly preferred embodiment, adjacent cells in the solid electrolyte layer are connected in series. But,
It is also possible to connect adjacent cells in parallel.

In a preferred embodiment, a plurality of first electrodes are provided on one surface of the solid electrolyte layer, and a plurality of second electrodes are provided on the other surface of the solid electrolyte layer. I have.

In a preferred embodiment, an end of a first electrode of one electrochemical cell and an end of a second electrode of another electrochemical cell adjacent to the electrochemical cell are solid. The electrodes are provided at positions facing each other with the electrolyte layer interposed therebetween, and the end of the first electrode and the end of the second electrode are electrically connected by a through-hole conductor. Here, that the end of the first electrode and the end of the second electrode are provided at positions facing each other with the solid electrolyte layer interposed therebetween is defined as a direction X perpendicular to the solid electrolyte layer (see FIG. 1). (See (a))). In this case, by providing a through-hole conductor in this overlapping region, the end of the first electrode and the end of the second electrode can be easily connected.

The electrochemical device of the present invention can be used as an oxygen pump or a high-temperature steam electrolysis cell in addition to a solid oxide fuel cell. This cell can be used for a hydrogen production device and a steam removal device. Further, the apparatus of the present invention can be used as a NOx, hydrocarbon, and carbon monoxide decomposition cell.

The first gas and the second gas may be the same or different. The types include an oxidizing gas, a reducing gas, an inert gas, and the like, and there is a preferred embodiment depending on the application.

In the case of a fuel cell, the first gas is an oxidizing gas and the second gas is a reducing gas. Examples of the oxidizing gas include air and oxygen. Examples of the reducing gas include a gas containing hydrogen, methane, carbon monoxide, and the like. In a fuel cell, the first electrode has a high potential,
The anode is the anode, and the second electrode has a low potential and is the cathode. In this case, the first electrode functions as a cathode and the second electrode functions as an anode.

Further, in the case of an oxygen pump, the first and second gases may be oxidizing or reducing gas. For example, the first gas is air or oxygen, the second gas is a process gas on the side into which oxygen is injected, and examples thereof include an inert gas. In this case, the first electrode acts as a cathode and acts as a cathode, and the second electrode acts as an anode and acts as an anode.

In the case of a NOx decomposing device or a water vapor removing device, the first gas is an inert gas or air. The second gas is a process gas containing NOx and water vapor, and is an inert gas, hydrogen, or methane in addition to exhaust gas from various internal combustion engines. In this case, the first electrode acts as a cathode and acts as a cathode, and the second electrode acts as an anode and acts as an anode.

Examples of the material of the solid electrolyte layer include lanthanum gallate, scandia-stabilized zirconia, and ytterbia-stabilized zirconia, in addition to yttria-stabilized zirconia, yttria partially-stabilized zirconia, and cerium oxide-based ceramics.

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 manganite may be doped with strontium, calcium, chromium, cobalt, iron, nickel, aluminum and the like.

The main raw materials of the cathode are nickel, nickel oxide, nickel-zirconia mixed powder, nickel oxide-zirconia mixed powder, palladium, platinum, palladium-zirconia mixed powder, platinum-zirconia mixed powder, nickel-ceria, nickel oxide-nickel. Ceria, palladium-ceria, platinum-ceria mixed powders and the like are preferred.

The materials of the through-hole conductors include metals such as iron, cobalt, nickel, copper, aluminum, silicon, gold, silver, platinum, palladium, ruthenium, molybdenum and tungsten, lanthanum chromite, lanthanum cobaltite, and lanthanum manganite. Preferred are conductive ceramics such as the above, a composite material of the aforementioned metal and ceramic, and a composite material of the aforementioned conductive ceramic and ceramic.

The present invention also provides an integrated electrochemical device comprising a plurality of the above-described electrochemical devices stacked.

In a preferred embodiment, an integrated electrochemical device comprises a plurality of the aforementioned electrochemical devices. And a peripheral wall portion made of ceramics and a through-hole conductor in the peripheral wall portion embedded in the peripheral wall portion,
A first gas passage and a second gas passage are formed inside the peripheral wall, a plurality of solid electrolyte layers are provided inside the peripheral wall, and the first electrode is provided in the first gas passage. And the second electrode faces the second gas passage.

FIGS. 2 to 4 relate to this embodiment. FIG. 2 is an exploded perspective view showing each layer of the integrated electrochemical device 30, FIG. 3 is a sectional view taken along line III-III of FIG. 2, and FIG. 4 is a sectional view taken along line IV-IV of FIG. .

In the examples shown in FIGS. 3 and 4, for example, five rows of electrochemical devices 5A to 5E are stacked and incorporated in an integrated electrochemical device. In FIG. 2, each part from the upper end of the device to the solid electrolyte layer 9D is shown as an exploded perspective view due to space restrictions.

The device 30 includes a plurality of electrochemical devices 9A-9.
It comprises a functional part 13 having E and a peripheral wall part 12 surrounding the functional part 13. The entire device 30 is manufactured by, for example, a green sheet laminating method. That is, the terminal layer 1A
And the end layers 1B, between the separator layers 8A, 8B, 8
C, 8D, 8E, 8F and electrochemical devices 9A, 9B, 9
C, 9D, and 9E are alternately stacked. In each of the separator layers 8A to 8F, a hollow portion having a planar shape as shown in FIG. 2 is formed, whereby a first gas passage 3 and a second gas passage 4 are formed.

Each of the electrochemical devices 9A to 9E is the same as the device described with reference to FIG. However, 15A, 1
5B is an electrochemical cell, 16A and 16B are first electrodes, and 17A and 17B are second electrodes. In addition,
In FIG. 2, each electrode on the solid electrolyte layer is not shown.

In this embodiment, the first gas passages 3 and the second gas passages 4 are provided alternately in the device 30.

The peripheral wall through-hole conductor 2A penetrates the terminal layer 1A, the separator layer 8A, and the solid electrolyte layer 9A. The conductor 2B penetrates the solid electrolyte layer 9A and the separator layer 8B. The conductor 2C penetrates through the separator layer 8C and the solid electrolyte layer 9C. Conductor 2
D penetrates the solid electrolyte layer 9C and the separator layer 8D. The conductor 2E penetrates through the separator layer 8E and the solid electrolyte layer 9E. The conductor 2F penetrates through the solid electrolyte layer 9E, the separator layer 8F, and the terminal layer 1B. In this example, in order to reduce the electric resistance in the conductor, two conductors are provided in each layer as shown in FIG. However, the number and shape of each conductor are not limited.

The electrode 17B of the cell 15A at the end of the electrochemical device 5A is connected to the peripheral wall through-hole conductor 2A. The electrode 16B of the cell 15A at the other end of the electrochemical device 5A extends to the inside of the peripheral wall portion 12 and is connected to the through-hole conductor 2B. Similarly, the electrode 17B of the cell 15B at the end of the electrochemical device 5B is connected to the through-hole conductor 2B, and the electrode 16B of the cell 15B at the other end extends to the inside of the peripheral wall portion 12, and It is connected to the body 2C. Similarly, the electrode 17B of the cell 15A at the end of the electrochemical device 5C is connected to the through-hole conductor 2C, and the electrode 1B of the cell 15A at the other end.
6B extends into the peripheral wall portion 12 and is connected to the through-hole conductor 2D. Similarly, the electrochemical device 5
The electrode 17B of the cell 15B at the end of D is connected to the through-hole conductor 2D, and the electrode 16B of the cell 15B at the other end.
B extends into the peripheral wall portion 12 and is connected to the through-hole conductor 2E. Similarly, the electrochemical device 5E
The electrode 17B of the cell 15A at the other end is connected to the through-hole conductor 2E, and the electrode 16B of the cell 15A at the other end.
Extends into the peripheral wall portion 12 and is connected to the through-hole conductor 2F. The conductors 2A and 2F are connected to external terminals (not shown).

FIG. 3 does not show a gas supply route to the first gas passage, the second gas passage, or a gas discharge route from each passage. Conventional methods can be used for such gas supply routes and discharge routes. For example, as shown in the exploded perspective view of FIG. 2 and the cross-sectional view of FIG. 4, gas is supplied from the first gas supply passage 10A to the first gas passage 3 and then another gas supply passage 10A.
Through B, gas can flow to the lower gas passage 3. Further, the gas flows through the gas supply passage 10C, the passage 3 and the discharge passage 10D, and is discharged outside the apparatus.

Similarly, the second gas supply passage 11A, the second gas passage 4, the gas supply passage 11B, the passage 4, the gas supply passage 1
Gas flows in the order of 1C, passage 4, and gas discharge passage 11D.

The operation and effect of such an embodiment will be described.

Since each electrode needs to have corrosion resistance to oxidizing gas and reducing gas, usable materials such as nickel-zirconia cermet and lanthanum manganite are limited. On the other hand, the peripheral wall through-hole conductors 2A to 2F do not need such corrosion resistance.
A high melting point metal that has high conductivity and does not melt or deform at the operating temperature of the ceramic is preferable. However, due to such a difference in the material, the contact insulation resistance between the through-hole conductor and the surface of each electrode increases.

In addition, when the temperature of such a structure increases, each electrode deforms following the deformation of the solid electrolyte layer. On the other hand, the peripheral wall portion through-hole conductor deforms mainly following the deformation of the ceramics constituting the separator layer. For this reason, due to the difference in the amount of deformation between the two, stress remains in the direction of arrow A (see FIG. 3) between the peripheral wall portion through-hole conductor and each electrode. For this reason, the contact state at the interface tends to be non-uniform.

For example, in the solid oxide fuel cell described in Japanese Patent Application Laid-Open No. 1-128359, each electrochemical cell is connected in parallel in such a structure. this is,
The voltage taken out from the electrochemical device is at most 0.7-1.0
It is on the order of volts, which means that the current value is large. Since the extraction voltage is constant, this amount of current increases in proportion to the number of electrochemical cells. On the other hand, it can be assumed that the interface has a large interface resistance for the above-mentioned reason, and that a very small part of the interface is in a state where the conductor and the electrode surface are in strong contact. In such a state, when a large current flows through the interface between the peripheral wall portion through-hole conductor and the electrode surface, the current is concentrated on a part of the interface, causing local heat generation, and it is thought that the structure near the interface is altered. Can be

In this embodiment, by connecting such electrochemical cells inside the peripheral wall in series, the take-out voltage is increased and the amount of current flowing through the interface between the through-hole conductor and the electrode surface is reduced. By doing so, local current concentration at the interface was reduced, and local remarkable heat generation was prevented.

In the embodiment shown in FIGS. 2 to 4, the solid electrolyte layer and the peripheral wall constituting the electrochemical cell are formed of the same ceramic solid electrolyte material and are integrated to form the same solid electrolyte layer. An integral structure made of material is produced.

When a thermal cycle is applied to such a structure, each electrode on the solid electrolyte layer is deformed following the thermal expansion and contraction of the solid electrolyte layer. At the same time, the peripheral wall portion through-hole conductor deforms following thermal expansion and contraction of the peripheral wall portion. At this time, by forming the peripheral wall and each solid electrolyte layer as a skeleton made of the same kind of material integrally as described above, the positional deviation between each electrode on the solid electrolyte layer and the end face of the peripheral wall through-hole conductor is reduced. Almost gone. In particular, the displacement of the electrode in the in-plane direction as shown by arrow A (see FIG. 3) can be eliminated.

In a preferred embodiment, the ceramic structure of the separator layer and the ceramic structure of the solid electrolyte layer are microscopically continuous.

In a preferred embodiment, the first electrode and the second electrode each extend into the peripheral wall, and are in direct contact with the end surface of the through-hole conductor. FIGS. 3 and 4 show such a configuration. Thereby, the electric resistance inside the device can be further reduced.

Preferably, the peripheral wall portion includes a plurality of separator layers hermetically surrounding the first gas passage and the second gas passage, and the solid electrolyte layer extends into the peripheral wall portion, and The ends are sandwiched between adjacent separator layers.

In a preferred embodiment, at least one of the first gas passages 3 is sandwiched between a pair of adjacent cells 15A and 15B, and each of the first electrodes of these cells has a first electrode. They face each other with one gas passage 3 interposed therebetween. Also, at least one of the second gas passages 4 is
It is sandwiched between a pair of adjacent cells 15A and 15B, and the respective second electrodes of these cells face each other across the second gas passage. By adopting such a design, the first gas passages and the second gas passages are alternately arranged with the cell interposed therebetween, so that no useless space is generated. Therefore, the efficiency per unit volume is increased.

The peripheral wall can be formed of insulating ceramics or solid electrolyte material. These are not particularly limited as long as they have corrosion resistance to the first gas passage and the second gas passage at the operating temperature of the electrochemical cell. Such insulating ceramics include alumina, mullite, magnesia spinel, calcia or magnesia stabilized zirconia. As the solid electrolyte type material, yttria-stabilized zirconia,
In addition to yttria partially stabilized zirconia and cerium oxide-based ceramics, lanthanum gallate, scandia stabilized zirconia, and ytterbia stabilized zirconia can be exemplified.

The fact that the ceramic solid electrolyte material forming the peripheral wall portion is the same as the material forming the solid electrolyte layer means that the basic components are the same.
In the case where there are a plurality of basic components, if the plurality of basic components are the same, it can be said that they are still the same type of ceramics even if the composition ratio of each basic component is different. Also,
A small amount of the dope component may be changed. If the basic composition is the same, the ceramic structure of the peripheral wall portion and the solid electrolyte layer is continuous after the integral sintering, and the joint disappears.

When the doping components are different between the ceramic constituting the peripheral wall portion and the ceramic constituting the solid electrolyte layer, the weight ratio of the different doping components is 10% by weight or less of the whole. Is preferred.

The method for producing the collective electrochemical device of the present invention is not limited, but from the viewpoint of productivity, production by the green sheet lamination method is particularly preferred. At this time, each layer as shown in FIGS. 1 and 2 is formed by a doctor blade method, a pressing method, an extrusion method, or the like to produce green sheets, which are laminated and sintered.

Examples of the organic binder that can be used for molding include polymethyl acrylate, nitrocellulose, polyvinyl alcohol, methyl cellulose, ethyl cellulose, starch, wax, acrylic acid polymer and methacrylic acid polymer. Examples of the pore former include cellulose, carbon, and acrylic powder.

In a preferred embodiment, a solid is placed between the end of the first electrode of one electrochemical cell and the end of the second electrode of another electrochemical cell adjacent to the electrochemical cell. An insulator separate from the electrolyte layer is interposed. This embodiment will be described below.

FIG. 5 is an enlarged cross-sectional view showing a connection portion between adjacent electrochemical cells in the electrochemical device of FIG. End 31 of first electrode 16C of one cell
And the end 32 of the second electrode 17D of the other cell are opposed to each other with the solid electrolyte layer 9 interposed therebetween. First electrode 16C
A gap 23 is provided between the second electrodes 17C and 16D, and a gap 24 is provided between the second electrodes 17C and 17D. The ends 31 and 32 are connected by a through-hole conductor 22.

The electrodes 16C and 17C belonging to the same cell,
When the oxygen ions O ₂ ⁻ move between 16D and 17D, electrons e ⁻ correspondingly move through the through-hole conductor 22.
To move. However, oxygen ions O ₂ ⁻ may move between the electrodes 16C and 17D or between the electrodes 16D and 17C belonging to different cells adjacent to each other. In particular, around the through-hole conductor 22, oxygen ions move between the ends 31 and 32 as shown by the arrow C. Further, oxygen ions move between the end of the electrode 17C and the electrode 16D as shown by the arrow E.

When these oxygen ions move, a closed circuit is formed around the through-hole conductor 22, and a part of the electromotive force generated in each adjacent cell is consumed. Becomes Further, the current flowing through the closed circuit consumes fuel and oxidant, which causes a decrease in fuel utilization.

In this embodiment, a solid electrolyte is provided between an end of a first electrode of one electrochemical cell and an end of a second electrode of another electrochemical cell adjacent to the electrochemical cell. An insulator separate from the layer is interposed. Thereby, the movement of oxygen ions between the ends as shown by the arrow C is suppressed or prevented at least, and the current loss can be reduced.

The position of the insulator is limited as long as it is between the end of the first electrode of one electrochemical cell and the end of the second electrode of another electrochemical cell adjacent to this electrochemical cell. Not done. For example, it may be on one surface 9c of the solid electrolyte layer 9, may be on the other surface 9d, and may be on the inner wall surface of the through hole 9a (that is, the side peripheral surface 22a of the through hole conductor 22).
Above), or may be buried inside the solid electrolyte layer 9.

It is necessary that the insulator separate from the solid electrolyte layer does not have oxygen ion permeability, but its insulation performance is a matter of design. However, for example, it is preferable that the volume resistivity of the insulator is 1000 Ω · cm or more.

As the material of the insulator, for example, alumina,
Examples include silica, mullite, magnesia, and alumina-magnesia spinel.

The thickness of the insulating layer is not particularly limited.
50 μm is preferred.

In a preferred embodiment, the insulator is an insulating layer provided between an end of the first electrode and the solid electrolyte layer, and the insulator is an end of the second electrode. It is an insulating layer provided between the part and the solid electrolyte layer. This allows the most efficient insulation between the ends.

In a preferred embodiment, a gap is provided between the first electrodes between a pair of adjacent electrochemical cells, and the insulating layer is exposed in the gap. In addition, a gap is provided between the second electrodes between a pair of adjacent electrochemical cells, and the insulating layer is exposed in the gap.

FIGS. 6 to 9 show an electrochemical device according to this embodiment. FIG. 6A shows an electrochemical device 3.
FIG. 6B is a cross-sectional view showing 5A, FIG. 6B is a plan view showing a state in which a through-hole conductor and an insulating layer are formed in the solid electrolyte layer 9, and FIG. 6C is a plan view of the device 35A. It is.

The apparatus 35A is provided with a plurality of, for example, four, electrochemical cells 15, and the respective cells 15 are connected in series. In the present embodiment, the solid electrolyte layer 9 has a rectangular flat plate shape when viewed two-dimensionally. Solid electrolyte layer 9
For example, four first electrodes 16 are formed on one surface 9c, and four second electrodes 17 are formed on the other surface 9d. B is the main working area of the electrochemical cell.

An elongated gap 23 is formed between adjacent first electrodes 16, and an elongated gap 24 is formed between adjacent second electrodes 17. The end 31 of each electrode 16 faces the end 32 of the electrode 17 of the adjacent cell with the solid electrolyte layer 9 interposed therebetween. In the solid electrolyte layer 9, a through-hole conductor 22 is provided in a region facing the above-mentioned end portion. Each through-hole conductor 22 allows the electrode 16 of the adjacent electrochemical cell 15
And 17 are connected in series.

In the periphery of the through-hole conductor 22,
On one surface 9c of the solid electrolyte layer 9, an insulating layer 25A,
5B, and the other surface 9d of the solid electrolyte layer 9
The insulating layers 25C and 25D are provided thereon. As a result, the insulating layers are interposed between the end portions of the respective electrodes and the surface of the solid electrolyte layer, thereby providing insulation. Gap 2
3, the insulating layer 25B is exposed.
D is exposed.

In a preferred embodiment, an insulator is provided between the through-hole conductor and the solid electrolyte layer, or an insulator is provided inside the through-hole conductor.

In FIG. 5, the through-hole conductor 22 itself is also connected to the electrodes 16C and 16D or to the electrode 17C.
C, 17D may act as a kind of electrode and consume power. Therefore, the through-hole conductor 2
By providing an insulator between the solid electrolyte layer 2 and the solid electrolyte layer 9, it is possible to prevent the through-hole conductor from acting as an electrode, thereby preventing power consumption.

FIGS. 7 to 9 relate to this embodiment. The electrochemical device 35B shown in FIGS. 7A to 7C is the same as the device 35A shown in FIG. 6 except that an insulating layer 25E is formed on the side peripheral surface of the through-hole conductor 22. The through-hole conductor 22 and the inner wall surface of the through-hole 9a are insulated.

In a preferred embodiment, the insulating layer extends in a direction perpendicular to the arrangement direction in which the plurality of electrochemical cells are arranged without being covered by the first electrode or the second electrode. Have. 8 and 9 relate to this embodiment.

The electrochemical device 35C shown in FIGS.
Is substantially similar to the device 35B of FIG. However, the planar shape of each through-hole conductor 22A is not circular but rectangular. In particular, as shown in FIG. 8C, the insulating layer includes an extension 25F that is not covered with the electrode 16 in a direction Y perpendicular to the arrangement direction Z in which the plurality of electrochemical cells are arranged. ing.

This embodiment has the advantage that the end of the electrode can be reliably insulated even if the relative position between the insulating layer and the electrode is shifted due to manufacturing errors. That is, in the embodiment shown in FIGS. 6 and 7, the edge of the electrode 16 and the edge of the insulating layers 25A and 25B are substantially collinear when viewed in the Y direction. Therefore, if the position of the insulating layers 25A and 25B and the position of the electrode 16 are displaced due to a manufacturing error, the edge of the electrode 16 and the insulating layers 25A and 25A,
The edge with 5B is shifted in the Y direction. As a result, a part of the end portion 31 of the electrode 16 comes into direct contact with one surface 9c of the solid electrolyte layer 9 without being insulated by the insulating layer. This results in the closed circuit described above.

On the other hand, by providing the extending portion 25F, even if the planar position between the electrode and the insulating layer is misaligned as described above, such misalignment is absorbed by the extending portion. As a result, insulation at the ends of the electrodes is ensured.

The electrochemical device 35D shown in FIGS. 9 (a)-(c)
Is substantially the same as the device 35C in FIG. However, in particular, as shown in FIG. 9 (b), in addition to the extending portion 25F, an extending portion 25G extending along the edge surface in the arrow Y direction in the action region B of each cell is formed.

[0076]

As described above, according to the present invention, in an electrochemical device having a structure in which a plurality of electrochemical cells are electrically connected, each gas reaching each electrode of each electrochemical cell is provided. Can be reduced, and the deterioration of the material of the connection portion between the adjacent electrochemical cells can be suppressed.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing an electrochemical device 5 according to one embodiment of the present invention, and FIG. 1B is a plan view of the device 5.

FIG. 2 is an exploded perspective view showing a part of the electrochemical device 5;

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV in FIG. 2;

FIG. 5 is an enlarged sectional view showing a connection portion between adjacent cells in the device 5 of FIG.

FIG. 6A is a cross-sectional view of an electrochemical device 35A, and FIG. 6B is a cross-sectional view of a through-hole conductor 2 in a solid electrolyte layer 9.
2 is a plan view showing a state where an insulating layer is formed;
(C) is a plan view of the device 35A.

FIG. 7A is a cross-sectional view of an electrochemical device 35B, and FIG. 7B is a cross-sectional view of a through-hole conductor 2 in a solid electrolyte layer 9;
2 is a plan view showing a state where an insulating layer is formed;
(C) is a plan view of the device 35B.

8A is a cross-sectional view of an electrochemical device 35C, and FIG. 8B is a cross-sectional view of a through-hole conductor 2 in a solid electrolyte layer 9;
2 is a plan view showing a state where an insulating layer is formed;
(C) is a plan view of the device 35C.

9A is a cross-sectional view of an electrochemical device 35D, and FIG. 9B is a cross-sectional view of a through-hole conductor 2 in a solid electrolyte layer 9;
2 is a plan view showing a state where an insulating layer is formed;
(C) is a plan view of the device 35D.

[Explanation of symbols]

1A, 1B End layers 2A, 2B, 2C, 2D,
2E, 2F Peripheral wall portion through-hole conductor 3 First gas passage 4 Second gas passage 5,
5A, 5B, 5C, 5D, 5E, 15 Electrochemical cell 17, 17A, 17B Second electrode 8A, 8
B, 8C, 8D, 8E, 8F Separator layer 9
A, 9B, 9C, 9D, 9E Solid electrolyte layer 9a Through hole 9c One surface 9d The other surface 10A, 10B, 10C, 10D First gas supply path 11A, 11B, 11C, 11D
Second gas supply path 12 Peripheral wall 13
Functional part 16, 16A, 16B First electrode 22, 22
A Through-hole conductor 23 Gap between first electrodes of adjacent cells 24
Gap between second electrodes of adjacent cells X direction perpendicular to solid electrolyte layer 9 Y direction perpendicular to array direction of multiple cells Z array direction of multiple cells

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kiyoshi Okumura 2-56 Sudacho, Mizuho-ku, Nagoya, Aichi Prefecture Inside Nihon Insulators Co., Ltd. (72) Inventor Ryu Takashi 2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi Prefecture No. Japan Insulator Co., Ltd. F-term (reference) 5H026 AA06 CC08 CV06 EE11

Claims (14)

[Claims] A solid electrolyte layer, a plurality of first electrodes provided on the solid electrolyte layer, and a plurality of second electrodes provided on the solid electrolyte layer; An electrochemical device in which a plurality of electrochemical cells are configured by one electrode and the second electrode, comprising: at least one through-hole conductor penetrating the solid electrolyte layer, wherein the solid electrolyte An electrochemical device, wherein at least two adjacent electrochemical cells in a layer are electrically connected via the through-hole conductor. 2. The plurality of first electrodes are provided on one surface of the solid electrolyte layer, and the plurality of second electrodes are provided on the other surface of the solid electrolyte layer. The device according to claim 1, characterized in that: 3. An end of the first electrode of one electrochemical cell and an end of the second electrode of another electrochemical cell adjacent to the electrochemical cell sandwich the solid electrolyte layer. And the end of the first electrode and the end of the second electrode are electrically connected by the through-hole conductor. An apparatus according to claim 1 or 2. 4. The solid electrolyte layer between an end of the first electrode of one electrochemical cell and an end of the second electrode of another electrochemical cell adjacent to the electrochemical cell. 2. An insulator separate from the intervening insulator.
An apparatus according to any one of claims 1 to 3. 5. The apparatus according to claim 4, wherein said insulator is an insulating layer provided between an end of said first electrode and said solid electrolyte layer. 6. The device according to claim 4, wherein the insulator is an insulating layer provided between an end of the second electrode and the solid electrolyte layer. 7. A gap between the first electrodes between a pair of adjacent electrochemical cells, wherein the insulator is exposed in the gap. −
Apparatus according to any one of the preceding claims. 8. A gap is provided between the second electrodes between a pair of adjacent electrochemical cells, and the insulator is exposed in the gap. −
Apparatus according to any one of the preceding claims. 9. The insulating layer includes an extending portion that is not covered by the first electrode or the second electrode in a direction perpendicular to an arrangement direction in which the plurality of electrochemical cells are arranged. 9. The method according to claim 5, wherein
Apparatus according to any one of the preceding claims. 10. The device according to claim 1, wherein an insulator is provided between the through-hole conductor and the solid electrolyte layer. 11. The method according to claim 1, wherein the at least two adjacent electrochemical cells are connected in series via the through-hole conductor. apparatus. 12. An integrated electrochemical device comprising a plurality of the electrochemical devices according to any one of claims 2 to 11, wherein the integrated electrochemical device is a ceramic peripheral wall and embedded in the peripheral wall. It has a through-hole conductor inside the peripheral wall,
A first gas passage and a second gas passage are formed inside the peripheral wall portion, the plurality of solid electrolyte layers are provided inside the peripheral wall portion, and the first electrode is the second gas passage. An integrated electrochemical device facing one gas passage, wherein the second electrode faces the second gas passage. 13. The device according to claim 12, wherein the pair of adjacent electrochemical devices are electrically connected in series by the through-hole conductor in the peripheral wall. 14. The apparatus according to claim 12, wherein said peripheral wall portion and said solid electrolyte layer are made of the same type of ceramic solid electrolyte material.