KR101348968B1 - Cathode for flat-tubular soide oxide cell and flat-tubular solid oxide cell and method for manufacturing the same and flat-tubular solid oxide fuel cell and flat-tubular solid oxide electrolyzer using the same - Google Patents

Abstract

The present invention relates to a flat tubular solid oxide unit cell, a method of manufacturing the same, a flat tubular solid oxide fuel cell and a flat tubular solid oxide water electrolysis device using the same, and specifically, by stacking a connecting material on one surface of a cathode, the thickness of the unit cell The present invention relates to a planar solid oxide unit cell capable of reducing the size of the cell stack and miniaturizing the cell stack, a method for manufacturing the same, and a planar solid oxide fuel cell and a planar solid oxide electrolytic device using the same.

Description

Cathode for flat tubular solid oxide unit cell, flat tubular solid oxide unit cell, manufacturing method thereof, flat tubular solid oxide fuel cell and flat tubular solid oxide electrolytic device using same CELL AND METHOD FOR MANUFACTURING THE SAME AND FLAT-TUBULAR SOLID OXIDE FUEL CELL AND METHOD FOR MANUFACTURING THE SAME AND FLAT-TUBULAR SOLID OXIDE ELECTROLYZER USING THE SAME}

The present invention relates to a cathode for a flat solid oxide unit cell, a flat solid oxide unit cell, a manufacturing method thereof, a flat tubular solid oxide fuel cell and a flat tubular solid oxide electrolytic device using the same.

In general, a fuel cell is a high-efficiency clean power generation technology that converts hydrogen and oxygen contained in a hydrocarbon-based material such as natural gas, coal gas, and methanol into electrical energy by an electrochemical reaction. The fuel cells are classified into alkali type, phosphoric acid type, molten carbonate, solid oxide and polymer fuel cell according to the type of electrolyte used.

The electrochemical reactors such as the solid oxide fuel cell and the high temperature water electrolytic device are classified into a plate type and a cylinder type according to their shape. The plate type has an advantage of high power density (output), but has a large gas sealing area. There is a disadvantage in that thermal shock occurs due to the difference in thermal expansion coefficient between materials during stacking and it is difficult to make a large area. The cylindrical shape has the advantage that the resistance to thermal stress and mechanical strength is relatively high and the large area can be manufactured by extrusion molding. However, there is a limit of low power density.

A flat tube type electrochemical reactor such as a flat tube type solid oxide fuel cell incorporating the advantages of the flat type and cylindrical type electrochemical reactors is disclosed in Korean Patent Laid-Open Publication No. 2005-0021027, US Pat. . The flat tubular electrochemical reactor also has a stack structure in which cells are stacked to increase output, but as the unit cell becomes thicker, the total thickness of the cell stack in which the unit cells are stacked increases, thereby increasing the power of the fuel cell. There is a problem that miniaturization is difficult.

Republic of Korea Patent Publication No. 2005-0021027 U.S. Patent # 7351477

SUMMARY OF THE INVENTION An object of the present invention is to reduce the thickness of a cell stack when stacking connection materials in a flat tubular solid oxide fuel cell or a flat tubular solid oxide electrolytic device configured by stacking a plurality of unit cells, thereby stacking a plurality of unit cells. The present invention provides a negative electrode for a flat tubular solid oxide unit cell, a unit cell for a flat tubular solid oxide fuel cell, or a unit cell for a flat tubular solid oxide electrolytic device.

Another object of the present invention is to reduce the manufacturing cost of a unit cell for a flat tube solid oxide fuel cell or a flat tube solid oxide hydrolysis device, and to reduce the size of the unit cell for a flat tube solid oxide fuel cell or a flat tube solid oxide electrolytic device. The present invention provides a cell, a planar solid oxide fuel cell, and a planar solid oxide hydroelectrolyzer using the same.

In order to achieve the above object, the present invention provides a cathode for a flat tubular solid oxide unit cell having a plurality of first gas flow therein, and no gas flow path therein.

In addition, the present invention is a flat tubular solid oxide unit cell comprising a negative electrode, an electrolyte layer, a positive electrode and a connecting material, the first gas flow portion is provided inside and the outside is a flat tubular cathode without a gas flow path; An electrolyte layer coated on the cathode; An anode laminated on the electrolyte layer coated on one surface of a flat cathode; And a connection material disposed on one surface of the cathode opposite to the surface on which the anode is stacked, and including a connection material including a flow path.

In addition, the present invention comprises the steps of: forming a flat cathode having a first gas flow portion therein, the outside of the gas flow channel; Coating an electrolyte layer on the cathode; Stacking a positive electrode on the electrolyte layer coated on one surface of the negative electrode; And laminating a connecting material including a flow path on one surface of the negative electrode opposite to the surface on which the positive electrode is stacked.

The present invention also provides a planar solid oxide fuel cell including a cell stack and a current collector in which a plurality of unit cells for the planar solid oxide fuel cell are stacked.

The present invention also provides a planar solid oxide electrolytic device including a cell stack and a current collector in which a plurality of unit cells for the flat solid oxide electrolytic device are stacked.

The present invention can reduce the manufacturing cost through a unit cell for a solid oxide fuel cell or a solid oxide electrolytic device, in which a connecting material including a connection part and a support part is stacked on one surface of a cathode, and a solid oxide fuel cell or a solid oxide hydroelectrolyte is provided. The device can be miniaturized.

In addition, the present invention can be laminated on the cathode by uniformly processing the connecting material by laminating the connecting material including the connecting portion and the support portion without forming irregularities for the second gas flow portion on the positive electrode.

1 is a view showing a cathode for a flat solid oxide unit cell of the present invention.
2 is a view showing a form of a cathode provided with a groove in which the connecting member of the present invention is accommodated.
3 is a view showing the form of a cathode provided in the form of a lattice of the connecting member of the present invention.
4 is a view showing the shape of the cathode provided in the grid form of the connecting member of the present invention.
5 is a diagram illustrating one embodiment of a cell stack in which unit cells of the present invention are stacked.
It is a figure which shows one form of the electrical power collector laminated | stacked on the cell stack of this invention.
It is a figure which shows one form of the electrical power collector laminated | stacked on the cell stack of this invention.

Hereinafter, the present invention will be described in detail.

In the solid oxide fuel cell, when hydrogen is supplied as a first gas to hydrogen and a second gas to each electrode of a unit cell including an electrolyte layer and cathodes and anodes located on both sides thereof, a reduction reaction of oxygen occurs at the anode to cause oxygen ions. The oxygen ions moved to the cathode through the electrolyte layer react with the hydrogen supplied to the cathode again to generate water. In this case, electrons are generated at the cathode and electrons are consumed at the anode, so that electricity flows when the two electrodes are connected to each other.

In addition, the solid oxide electrolytic device employs the solid oxide fuel cell, and is an apparatus for forming hydrogen by electrolysis of water vapor by a reverse reaction of the solid oxide fuel cell.

The present invention provides a cathode for a flat tubular solid oxide unit cell having a plurality of first gas flows therein and having no gas flow path therein. When there is no gas flow path in the outside, unlike the cathode in which the existing flow path is formed, the manufacturing process is simple, and it is possible to control the non-uniform coating of the connection material on the flow path formed on the cathode, so that the solid oxide fuel cell or the solid oxide number The efficiency of the electrolytic device can be improved.

The present invention relates to a unit cell for a solid-state solid oxide fuel cell or a solid oxide electrolytic device including a cathode, an electrolyte layer, an anode, and a connecting material, wherein the first gas flow part is provided inside and there is no gas flow path outside. cathode; An electrolyte layer coated on the cathode; An anode laminated on the electrolyte layer coated on one surface of a flat cathode; And it provides a unit cell for a flat-shaped solid oxide fuel cell or a solid oxide electrolytic device including a connecting material which is placed on one surface of the negative electrode opposite the stacked surface of the positive electrode and includes a flow path.

In the unit cell for the planar solid oxide fuel cell or the solid oxide electrolytic device, the connecting member serves to connect electricity so that electricity can flow between the stacked unit cells when a plurality of unit cells are stacked. It is preferable that the cathode of the present invention is a flat tube-shaped cathode without a separate gas flow path to the outside, and the connection member preferably includes a flow path for forming the second gas flow portion. At this time, the connecting material is preferably placed on one surface of the flat-shaped negative electrode, through which a connection of a uniform thickness can be laminated on the negative electrode without going through a manufacturing process for forming a separate flow path in the negative electrode. That is, in contrast to the conventional cathode in which additional manufacturing costs are incurred to provide the second gas flow portion, the cathode of the present invention does not have a separate second gas flow portion.

Accordingly, the second gas flow part may be provided by the connection part included in the connection material, thereby reducing the manufacturing cost, and reducing the thickness of the cell stack in which the plurality of unit cells are stacked by reducing the thickness of the unit cell. . In addition, the anode is not provided with a separate second gas flow portion, and by stacking the connecting material, the connecting material can be laminated with a uniform thickness, and the connecting material is not only sprayed for laminating the conventional connecting material, but also through the screen printing method coating. It can be laminated on the cathode.

The connecting member includes a plurality of connecting parts, and the plurality of connecting parts preferably form a lattice. The plurality of connection parts may form a lattice, and may be stacked between the cathode of one unit cell and the anode of the other unit cell to form a flow path so that the second gas may flow.

It is preferable that the connecting member includes a connecting portion and a supporting portion. When the connecting material is laminated on the negative electrode, the supporting part supporting the connecting part is preferably stacked in a groove formed on one surface of the negative electrode, thereby reducing the thickness of the unit cell. Through this, the thickness of the cell stack provided by stacking a plurality of unit cells can be reduced, and as a result, the size of the solid oxide fuel cell or the solid oxide electrolytic device can be reduced.

When the connection unit is stacked with one unit cell and the other unit cell, it is preferable to protrude to the outside of the unit cell to form a second gas flow portion, and through the second gas flow portion is a flat tubular solid oxide fuel cell or flat tubular The side of the solid oxide electrolyzer may be supplied with air or water vapor as a second gas to generate electricity or to produce hydrogen.

In addition, the connecting material is any one material selected from the group consisting of platinum, cropper alloy, silicon carbide, and a composite containing silicon carbide and carbon, in order to reduce the electrical conductivity change with temperature change and reduce the resistance. It is preferable that it is made.

In addition, the connecting material is preferably made of any one material selected from the group consisting of metal foam and ceramic foam. The metal foam or the ceramic foam is one of porous materials, and may provide a flow path through which the second gas flows through the connecting material, thereby increasing efficiency of the solid oxide fuel cell or the solid oxide hydrolysis device.

The present invention comprises the steps of: forming a flat cathode having a first gas flow part therein, and having no gas flow path therein; Coating an electrolyte layer on the cathode; Stacking a positive electrode on the electrolyte layer coated on one surface of the negative electrode; And stacking a connecting material including a flow path on one surface of the cathode opposite to the surface on which the anode is stacked.

In the case of the manufacturing method, by using a negative electrode having no gas flow path on the outside, the unit cell including a connecting material including a plurality of connecting portions spaced apart from each other for the second gas flow portion is stacked on the negative electrode, It is preferable to manufacture the unit cell through which the connection material having a uniform thickness is reduced, and the thickness of the flat cell having a reduced thickness can be manufactured.

The present invention provides a flat tubular solid oxide fuel cell including a cell stack and a current collector in which a plurality of the flat tubular solid oxide unit cells are stacked. In this case, it is preferable that the plurality of unit cells are stacked to be stacked so that the connection portion of the connection material of one unit cell and the anode of the other unit cell are bonded to each other. It is preferable to have a.

The present invention provides a flat tubular solid oxide electrolytic device including a cell stack and a current collector in which a plurality of unit cells for the flat tubular solid oxide electrolytic device are stacked. In this case, it is preferable that the plurality of unit cells are stacked to be stacked so that the connection portion of the connection material of one unit cell and the anode of the other unit cell are bonded to each other. It is preferable to provide. The solid oxide electrolytic device is a device for generating hydrogen fuel using a reverse reaction of the reaction occurring in the solid oxide fuel cell, supplying water to the positive electrode, and supplying electricity through the current collector stacked on the top and bottom, It is a device that can produce hydrogen.

Preferably, the current collector is provided with irregularities at a portion to be joined to the flat tubular solid oxide unit cell. Through the concavities and convexities, a solid oxide fuel cell or a solid oxide electrolytic device can be manufactured without the need for adding a separate connection material when the unit cell and the current collector are joined, and the resistance can be increased to increase the efficiency of the fuel cell.

Hereinafter, the present invention will be described in detail by way of examples.

However, the following examples are illustrative of the present invention, and the present invention is not limited to the following examples.

< Example  One: Flat tubular  Fabrication of Solid Oxide Unit Cells>

As shown in FIG. 1, the cathode 11 was shape | molded so that the 1st gas flow part 111 may be comprised inside using the ceramic extrusion molding machine, and both ends were sealed. Thereafter, holes are formed at both ends of the dried formed body for connecting the first gas flow portions 111 between the unit cells. Then, in order to coat the connecting material 14 on the negative electrode 11 as shown in FIG. 3, the connecting material 14 made of silicon carbide (SiC) was coated on one surface of the negative electrode 11. In this case, the connecting material is silicon carbide (SiC bulk), silicon carbide (SiC) fiber composite, Croper, Inconel, Silver (Ag), gold (Au), platinum (Pt), Perovskite It may be prepared using a ceramic-based tape (LSM, LSCF, etc.) tape or a porous foam, but is not limited thereto.

In this case, the connecting portion of the connecting member is coated to protrude to the outside of the unit cell to form a second gas flow, and the electrolyte layer 13 is coated on the surface of the negative electrode 11 which is not coated with the connecting member 14. Then, the connection material 14 and the electrolyte layer 13 were heat-treated at 1350 to 1400 ° C. to form a dense layer. Subsequently, the anode 12 was coated on the opposite side of the surface on which the connecting member 14 was coated, the anode 12 was coated, and heat-treated at 900 to 1200 ° C. to prepare a flat solid oxide unit cell. .

< Example  2: Flat tubular  Fabrication of Solid Oxide Unit Cells>

Using a ceramic extrusion machine, the cathode 11 was molded so that the first gas flow part 111 was formed therein, and both ends thereof were sealed. Thereafter, holes are formed at both ends of the dried formed body for connecting the first gas flow portions 111 between the unit cells. Subsequently, in order to coat the connecting member 14 on the negative electrode 11, a connecting member accommodating groove 112 may be formed on one surface of the negative electrode 11 to accommodate the supporting portion of the connecting material on the negative electrode as shown in FIG. The grooves 112 were coated with a connecting member 14 made of silicon carbide (SiC). In this case, the connecting material is silicon carbide (SiC bulk), silicon carbide (SiC) fiber composite, Croper, Inconel, Silver (Ag), gold (Au), platinum (Pt), Perovskite It may be prepared using a ceramic-based tape (LSM, LSCF, etc.) tape or a porous foam, but is not limited thereto.

In this case, the connecting portion of the connecting member 14 is coated so as to protrude out of the unit cell to form a second gas flow portion, and the electrolyte layer 13 on the surface of the negative electrode 11 on which the connecting member 14 is not coated. After the coating, the connection material 14 and the electrolyte layer 13 were heat-treated at 1350 to 1400 ° C. to form a dense layer. Subsequently, the anode 12 was coated on the opposite side of the surface on which the connecting member 14 was coated, the anode 12 was coated, and heat-treated at 900 to 1200 ° C. to prepare a flat solid oxide unit cell. .

< Example  3: Flat tubular  Fabrication of Solid Oxide Unit Cells>

As shown in FIG. 1, the cathode 11 was shape | molded so that the 1st gas flow part 111 may be comprised inside using the ceramic extrusion molding machine, and both ends were sealed. Thereafter, holes are formed at both ends of the dried formed body for connecting the first gas flow portions 111 between the unit cells. Thereafter, as shown in FIG. 3, a lattice connecting member 14 made of silicon carbide fibers was coated on one surface of the cathode 11. In this case, the connecting portion of the connecting member 14 is coated so as to protrude out of the unit cell to form a second gas flow portion, and the electrolyte layer 13 on the surface of the negative electrode 11 on which the connecting member 14 is not coated. After the coating, the connection material 14 and the electrolyte layer 13 were heat-treated at 1350 to 1400 ° C. to form a dense layer. Subsequently, the anode 12 was coated on the opposite side of the surface on which the connecting member 14 was coated, the anode 12 was coated, and heat-treated at 900 to 1200 ° C. to prepare a flat solid oxide unit cell. .

< Example  4: Flat tubular  Fabrication of Solid Oxide Fuel Cells>

FIG. 5 is a view showing a flat tube solid oxide fuel cell manufactured by stacking the unit cells prepared in Example 1. FIG. As shown in FIG. 5, a plurality of the unit cells are stacked, and at this time, the connection material 14 of one unit cell and the anode 12 of the other unit cell are laminated so as to be bonded.

Subsequently, a solid oxide fuel cell may be manufactured by providing current collectors 15 at upper and lower ends of the stacked unit cells, wherein the current collector 15 at the upper end may have the unevenness 153 shown in FIG. 6 or 7. With a current collector 15 including a, since a separate connecting member 14 is not used between the current collector 15 and the cell stack can increase the efficiency of the fuel cell.

Hydrogen is injected into the first gas through the first gas injection unit of the lowermost unit cell of the stacked unit cells to flow along the first gas flow unit, and air is laterally injected into the second gas to flow along the second gas flow unit. Thus, electricity can be generated.

Cathode: 11 First gas flow section: 111
Connector Storage Groove: 112 Anode: 12
Electrolyte layer: 13 Connecting material: 14
Current collector: 15 Current collector: 151
Manifold: 152 Unevenness: 153

Claims (12)

delete In the flat-type solid oxide unit cell comprising a negative electrode, an electrolyte layer, a positive electrode and a connecting material,
A flat cathode having a first gas flow part therein and no gas flow path therein;
An electrolyte layer coated on the cathode;
An anode laminated on the electrolyte layer coated on one surface of a flat cathode; And
It includes a connecting material including a flow path is placed on one side of the negative electrode opposite the laminated surface of the positive electrode,
The connecting member includes a plurality of connecting parts and a supporting part, and when the connecting part is stacked with one unit cell and the other unit cell, the tubular member may protrude out of the unit cell to form a second gas flow part. Solid oxide unit cell. The flat tubular solid oxide unit cell of claim 2, wherein the connection member is stacked in a groove formed on one surface of the cathode. The flat tubular solid oxide unit cell of claim 2, wherein the connection material comprises a plurality of connection parts, and the plurality of connection parts form a lattice. delete 3. The planar solid oxide unit cell of claim 2, wherein the connection material is made of any one material selected from the group consisting of platinum, a cropper alloy, silicon carbide, and a composite including silicon carbide and carbon. 4. The planar solid oxide unit cell of claim 2, wherein the connection material is made of any one material selected from the group consisting of metal foams and ceramic foams. Forming a flat cathode having a first gas flow part therein and having no gas flow path therein;
Coating an electrolyte layer on the cathode;
Stacking a positive electrode on the electrolyte layer coated on one surface of the negative electrode; And
Laminating a connecting material including a flow path on one surface of the negative electrode opposite to the surface on which the positive electrode is stacked; A flat tubular solid oxide fuel cell comprising a cell stack and a current collector in which at least two flat tubular solid oxide unit cells are stacked. 10. The flat tubular solid oxide fuel cell as set forth in claim 9, wherein the current collector is provided with irregularities at portions joined to the cell stack. A flat tubular solid oxide electrolytic device comprising a cell stack and a current collector in which at least two flat tubular solid oxide unit cells are stacked. The flat tubular solid oxide electrolytic device according to claim 11, wherein the current collector is provided with irregularities at a portion to be bonded to the cell stack.

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