KR101960136B1 - Fuel cell and method for manufacturing same - Google Patents

Abstract

A method of manufacturing a fuel cell is provided. The method for manufacturing a fuel cell includes the steps of: physically mixing a first metal oxide and a second metal oxide to form a base combination; forming the base combination in a thin layer type preliminary electrode support electrode support, and doping the preliminary electrode support with gadolinium (Gd) to produce an electrode support.

Description

[0001] Fuel cell and method for manufacturing same [0001]

The present invention relates to a fuel cell and a method of manufacturing the same, and more particularly, to a fuel cell including a cathode support doped with gadolinium (Gd), a cathode and an electrolyte membrane further doped with gadolinium (Gd) .

Fuel cells are devices that convert the change of free energy electrochemically reacting fuel and oxygen into electric energy. A solid oxide fuel cell using an ion conductive oxide as an electrolyte has the highest energy conversion efficiency among the fuel cells that have been developed up to now to produce electric energy and thermal energy at a high temperature of about 600 to 1000. It has the advantage of using various raw materials such as natural gas and coal gas as a fuel due to operation at high temperature and it has advantages such as corrosion and loss of materials by using solid electrolyte and solid electrode, have. In addition, when hydrogen is used as fuel, only pure water is discharged and it is attracting much attention because it can be used as a future clean energy source.

The solid oxide fuel cell has a cathode structure that reacts with an oxygen ion conductive electrolyte and oxygen in the air to react with oxygen ions and oxygen ions moved through the oxygen ion electrolyte to hydrogen or carbon to form water or carbon dioxide And an anode or anode that reacts and emits electrons. The battery composed of the air electrode / electrolyte / fuel electrode is called a single cell. Since the driving force for causing the reaction between the air electrode and the fuel electrode is represented by the difference in oxygen partial pressure between the air electrode and the fuel electrode, air or fuel flowing into the anode is not mixed It becomes very important not to. The shape of a single cell can be divided into a tubular type and a planar type. In the case of a cylindrical type, there is an advantage of facilitating the gas separation. However, the shape of the current collector connecting the unit cell and the unit cell, There is a drawback that the energy loss is large. The flat plate type exhibits low energy loss characteristics due to its structural characteristics that can easily connect the entire electrode with the current collector.

SUMMARY OF THE INVENTION The present invention provides a fuel cell with reduced manufacturing cost and a method of manufacturing the fuel cell.

It is another object of the present invention to provide a fuel cell having improved electronic conductivity and a method of manufacturing the fuel cell.

Another aspect of the present invention is to provide a fuel cell having improved ion conductivity and a method of manufacturing the fuel cell.

 It is another object of the present invention to provide a fuel cell having improved power generation efficiency by fuel and a method of manufacturing the fuel cell.

The technical problem to be solved by the present invention is not limited to the above.

In order to solve the above-mentioned technical problems, the present invention provides a method of manufacturing a fuel cell.

According to one embodiment, a method of manufacturing a fuel cell includes the steps of: physically mixing a first metal oxide and a second metal oxide to form a base combination; forming the base combination in a thin layer form Preparing a preliminary electrode support, and doping the preliminary electrode support with gadolinium (Gd) to produce an electrode support.

According to one embodiment, the first metal oxide comprises cerium (Ce) oxide and the second metal oxide may comprise nickel (Ni) oxide.

According to one embodiment, a method of manufacturing a fuel cell includes the steps of: sintering a sintering aid to the first metal oxide and the second metal oxide before physically mixing the first metal oxide and the second metal oxide And then adding and mixing.

According to one embodiment, the sintering aids may include divalent or trivalent metal oxides.

According to one embodiment, the physical mixing of the first metal oxide and the second metal oxide is performed by supplying a solvent and a dispersant to the first metal oxide and the second metal oxide, A first physical mixing and a second physical mixing performed by supplying a bonding agent and a plasticizer to the first metal oxide and the second metal oxide on which the first physical mixing process has been performed, And may include a second physical mixing.

According to one embodiment, the physical mixing of the first metal oxide and the second metal oxide may include ball milling the first metal oxide and the second metal oxide.

According to one embodiment, a method of manufacturing a fuel cell includes forming an anode and an electrolyte layer on the preliminary electrode support in order before doping the preliminary electrode support with gadolinium (Gd) .

According to one embodiment, a method of manufacturing a fuel cell further comprises providing the cathode and the electrolyte membrane on the preliminary electrode support, and then providing heat and pressure to the preliminary electrode support, the cathode, and the electrolyte membrane .

According to one embodiment, the step of doping the preliminary electrode support with gadolinium (Gd) may comprise immersing the preliminary electrode support, the cathode, and the electrolyte membrane in a solution comprising gadolinium (Gd) .

According to one embodiment, the step of doping the preliminary electrode support with gadolinium (Gd) may include dipping the preliminary electrode support, the cathode, and the electrolyte membrane in a solution containing gadolinium (Gd) treatment may be further included.

According to one embodiment, the step of heat-treating the preliminary electrode support, the cathode, and the electrolyte membrane may include doping gadolinium (Gd) on the preliminary electrode support, the cathode, and the electrolyte membrane.

In order to solve the above technical problems, the present invention provides a fuel cell.

According to one embodiment, the fuel cell comprises an anode support comprising a nickel oxide and a cerium oxide compound doped with gadolinium (Gd), a nickel oxide and a gadolinium doped with gadolinium (Gd) Ceria) compound, and an electrolyte layer comprising a GDC additionally doped with gadolinium (Gd).

According to one embodiment, the cathode support may comprise a divalent or trivalent metal oxide.

According to an embodiment of the present invention, a base joint formed by physically mixing a first metal oxide and a second metal oxide is formed into a thin-film preliminary electrode support, and then the preliminary electrode support is divided into a plurality of (Gd) -doped electrode support, which can be applied to a fuel cell. As a result, the use of gadolinium (Gd) -doped cerium oxide, which is in the form of expensive powder, is minimized, and the production cost of the fuel cell can be reduced.

Also, after the cathode and the electrolyte membrane are formed on the preliminary electrode support, the preliminary electrode support, the cathode, and the electrolyte membrane may be immersed together in the solution containing gadolinium (Gd). Accordingly, gadolinium (Gd) is doped in the electrode support, the cathode, and the electrolyte membrane, so that ion conduction characteristics of the electrode support, the cathode, and the electrolyte membrane can be improved. Further, a fuel cell having improved interfacial characteristics between the electrode support, the cathode, and the electrolyte membrane and having high reliability and high energy efficiency, and a method of manufacturing the fuel cell can be provided.

1 is a flowchart illustrating a method of manufacturing a fuel cell according to an embodiment of the present invention.
2 is a view for explaining a step of forming a base combination included in a method of manufacturing a fuel cell according to an embodiment of the present invention.
3 is a cross-sectional view illustrating a step of forming a preliminary electrode support included in a method of manufacturing a fuel cell according to an embodiment of the present invention.
4 is a cross-sectional view illustrating a step of forming an electrode support included in a method of manufacturing a fuel cell according to an embodiment of the present invention.
5 is a cross-sectional view illustrating a fuel cell manufactured according to an embodiment of the present invention.
6 is an enlarged view of A of an electrode support manufactured according to an embodiment of the present invention.
7 is a cross-sectional view illustrating a step of forming an electrode support by doping gadolinium (Gd) on a preliminary electrode support according to a first modification of the present invention.
FIG. 8 is a cross-sectional view for explaining that a preliminary electrode support and a cathode according to a second modification of the present invention are doped with gadolinium (Gd) to form a cathode in which an electrode support and gadolinium are additionally doped.
9 and 10 are SEM photographs of a cathode support included in a fuel cell according to an embodiment of the present invention.
11 is a graph showing XPS data of a cathode support included in a fuel cell according to an embodiment of the present invention.
12 is a graph showing electrical characteristics of a fuel cell according to Examples and Comparative Examples of the present invention.
13 is a view for explaining an example of a fuel cell system for power generation using the fuel cell manufactured according to the embodiment of the present invention and modifications thereof.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In this specification, when an element is referred to as being on another element, it may be directly formed on another element, or a third element may be interposed therebetween. Further, in the drawings, the thicknesses of the films and regions are exaggerated for an effective explanation of the technical content.

Also, while the terms first, second, third, etc. in the various embodiments of the present disclosure are used to describe various components, these components should not be limited by these terms. These terms have only been used to distinguish one component from another. Thus, what is referred to as a first component in any one embodiment may be referred to as a second component in another embodiment. Each embodiment described and exemplified herein also includes its complementary embodiment. Also, in this specification, 'and / or' are used to include at least one of the front and rear components.

The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It is also to be understood that the terms such as " comprises "or" having "are intended to specify the presence of stated features, integers, Should not be understood to exclude the presence or addition of one or more other elements, elements, or combinations thereof.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

FIG. 1 is a flow chart for explaining a method of manufacturing a fuel cell according to an embodiment of the present invention, FIGS. 2 to 5 are views for explaining a method of manufacturing a fuel cell according to an embodiment of the present invention, Fig. 4 is an enlarged view of Fig.

Referring to FIGS. 1 and 2, the first metal oxide 10 and the second metal oxide 20 are physically mixed to form a base combination 30 (S100). The base coupling body 30 may be formed by physically coupling the first metal oxide 10 and the second metal oxide 20 by the physical mixing. The first metal oxide 10 and the second metal oxide 20 may be cerium (Ce) oxide and nickel (Ni) oxide. For example, the first metal oxide 10 may be cerium oxide (CeO ₂ ), and the second metal oxide 20 may be nickel oxide (NiO).

The physical mixing may include a first physical mixing process and a second physical mixing process. For example, the physical mixing may be a ball milling process.

The first physical mixing step may include ball milling a mixture of a solvent and a dispersant in the first metal oxide 10 and the second metal oxide 20. The solvent may be organic solvents. For example, the solvent may be ethyl alcohol or toluene. In addition, the dispersing agent may be manhattan fish oil. For example, the ethyl alcohol and / or the toluene as the solvent and the manhaden fish oil as the dispersant are mixed in the first metal oxide 10 and the second metal oxide 20, Ball milling can be performed. For example, the dispersant may be supplied at 1 wt% of the first metal oxide 10 and the second metal oxide 20.

The second physical mixing process may be performed by bonding a bonding agent and a plasticizer to the first metal oxide 10 and the second metal oxide 20 after the first physical mixing process is performed And ball milling. The binder may be a vinyl based binder, and the plasticizer may be a phthalate plasticizer. For example, the binder may be PVB (polyvinyl butyral) or PVA (polyvinyl alcohol), and the plasticizer may be selected from the group consisting of Butylbenzyl phthalate (BBP), Dibutyl phthalate (DBP) or Di- . ≪ / RTI > For example, after BBP, which is the plasticizer, and PVB, which is the binder, are mixed with the first metal oxide 10 and the second metal oxide 20 on which the first physical mixing process has been performed, Milling can be performed.

According to one embodiment, before the first metal oxide 10 and the second metal oxide 20 are physically mixed, the first metal oxide 10 and the second metal oxide 20 are sintered A sintering aid may be added and mixed. The sintering aid may be a divalent or trivalent metal oxide. For example, the sintering aid may be any one of magnesium oxide (MgO), calcium oxide (CaO), manganese oxide (MnO), and iron oxide (Fe ₂ O ₃ ).

1 and 3, the base assembly 30 manufactured according to the embodiment of the present invention may be manufactured as a thin layer type preliminary electrode support 100 (S200) . The preliminary electrode support 100 may be formed by subjecting the base assembly 30 to a tape casting process. For example, the spare electrode support produced by the tape casting may be in the form of a thin film having a thickness of 500 탆 to 1000 탆.

Referring to FIGS. 1 and 4, an electrode support 120 may be manufactured by doping gadolinium (Gd) on the spare electrode support 100 manufactured according to an embodiment of the present invention (S300). The method of doping gadolinium (Gd) in the preliminary electrode support 100 may include a step of immersing the preliminary electrode support 100 in a solution 500 containing gadolinium (Gd) and a thermal treatment May be performed in order.

The step of immersing the preliminary electrode support 100 in the solution 500 containing gadolinium (Gd) may be performed by immersing the preliminary electrode support 100 in a solution 500 containing gadolinium (Gd), for example, , Or in a Gadolinium nitrate solution. The concentration of the gadolinium nitrate solution may be 0.1 to 1.0 M, and Gd-nitrate hexahydrate may be dissolved in Ethyl alcohol.

Also, the preliminary electrode support 100 may be heat treated by immersing the preliminary electrode support 100 in the solution 500 containing gadolinium (Gd), followed by drying. For example, after the preliminary electrode support 100 is immersed in the solution 500 containing gadolinium (Gd), the preliminary electrode support 100 may be heat-treated at 1400 ° C to 1500 ° C for 4 hours. The type of the heater used in the heat treatment is not particularly limited. For example, the heater may be any one of a heater, a hot plate, and a heating coil.

According to one embodiment, the anode 200 and the electrolyte membrane (not shown) are formed on the preliminary electrode support 100 before the preliminary electrode support 100 is immersed in the solution 500 containing gadolinium (Gd) an electrolyte layer 300 may be formed in this order.

The cathode 200 may comprise the second metal oxide 20 and a GdC (Gd-doped Ceria) compound, and as described with reference to FIGS. 1 and 2, the physical mixing Mixing, and second physical mixing), and then subjected to the tape casting process to produce a thin film. For example, the cathode 200 may be formed by performing physical mixing (first physical mixing, second physical mixing) of the second metal oxide NiO and GdC , The tape casting process may be performed to produce a thin film having a thickness of 5 to 20 占 퐉.

The electrolyte membrane 300 may include a GDC (Gd-doped Ceria), and the GDC (Gd-doped Ceria) as described with reference to FIGS. 1 and 2 Likewise, after the physical mixing (first physical mixing, second physical mixing), the tape casting process can be processed to form a thin film. For example, the electrolyte membrane 300 may be formed by subjecting GDC (Gd-doped ceria) to physical mixing (first physical mixing, second physical mixing) Thin-film < / RTI >

The anode 200 and the electrolyte membrane 300 are sequentially stacked on the preliminary electrode support 100 and then the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 are heat- And pressure can be provided. For example, the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 stacked in this order are disposed between the heated metal plates, and the preliminary electrode support 100 ), The cathode 200, and the electrolyte membrane 300 may be provided with heat and pressure.

Pre-sintering may also be performed after heat and pressure are applied to the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300, which are sequentially stacked. The pre-sintering may include a first pre-sintering and a second pre-sintering, wherein the first pre-sintering and the second pre-sintering are sequentially .

The primary pre-sintering may be such that heat is supplied to the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300. By the above primary sintering, the plasticizer and the binder contained in the preliminary electrode support 100 can be removed. For example, the primary pre-sintering may be performed for one hour at 150, 300, and 550 degrees, respectively.

The secondary pre-sintering may be such that heat is supplied to the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300, similarly to the primary pre-sintering. By the secondary pre-sintering, the mechanical strength of the preliminary electrode support 100 can be improved. For example, the secondary pre-sintering may be performed at 900 degrees for 2 hours.

As described above, the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 are formed in the same manner as the preliminary electrode support 100 in order to improve the chemical / physical characteristics of the preliminary electrode support 100, And the second pre-sintering may be performed. The pre-sintering process and the secondary pre-sintering process of the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 may be performed by using the preliminary electrode support 100, And the electrolyte membrane 300 are disposed between the porous ceramic supports and the porous ceramic supports are attached to the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 Heat may be provided. The type of the heater that supplies heat to the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 through the porous ceramic supports is not particularly limited. For example, the heater may be any one of a heater, a hot plate, and a heating coil.

The cathode 200 and the electrolyte membrane 300 are formed on the preliminary electrode support 100 before the preliminary electrode support 100 is immersed in the solution 500 containing gadolinium (Gd) The negative electrode 200 and the electrolyte membrane 300 as well as the spare electrode support 100 may be immersed in the solution 500 containing gadolinium (Gd). When the preliminary electrode support 100, the cathode 200 and the electrolyte membrane 300 are immersed in the solution 500 containing gadolinium (Gd), the preliminary electrode support 100, the cathode 200 And the surface of the electrolyte membrane 300 may be coated with gadolinium (Gd). Thereafter, gadolinium (Gd) coated on the surfaces of the preliminary electrode support 100, the cathode 200 and the electrolyte membrane 300 is heat-treated to separate the preliminary electrode support 100, the cathode 200, And may be doped in the electrolyte membrane 300.

5, a cathode 400 is formed on the electrolyte membrane 300 after the preliminary electrode support 100, the cathode 200 and the electrolyte membrane 300 are doped with gadolinium (Gd) So that the fuel cell according to the embodiment of the present invention can be manufactured. The anode 400 may include a Gd-doped ceria doped with gadolinium (Gd). In addition, the anode 400 may be manufactured in the form of a thin film by a heat treatment after a screen printing process. For example, the anode 400 may be manufactured by a screen printing process to form a thin film of LSCF-GDC (Lanthanum-Strontium-Cobalt-Ferric Oxide-Gd doped Ceria) paste, Lt; / RTI > for 2 hours.

The doping of gadolinium (Gd) with respect to the preliminary electrode support 100, the cathode 200 and the electrolyte membrane 300 can be carried out by using the first metal oxide 10 included in the preliminary electrode support 100, GdC (GdC) contained in the cathode 200 and the electrolyte membrane 300 can be caused to react with the solution 500 containing gadolinium (Gd). In other words, gadolinium (Gd) is added to GDC (Gd-doped ceria) contained in the first metal oxide 10, the cathode 200, and the electrolyte membrane 300 included in the preliminary electrode support 100, Can be doped.

The cathode 200 comprising nickel oxide and a GdC (Gd-doped Ceria) compound is further doped with gadolinium (Gd) to form a Gd-doped Ceria doped with nickel oxide and gadolinium (Gd) . ≪ / RTI > In addition, the electrolyte membrane 300 including a GdC (Gd-doped ceria) compound may be further doped with gadolinium (Gd) to include GdC (Gd-doped Ceria) further doped with gadolinium . In other words, the cathode 200 and the electrolyte membrane 300 including GdC (Gd-doped Ceria), which is a compound already doped with gadolinium (Gd), can be formed in the solution 500 containing the gadolinium (Gd) And then heat-treated, gadolinium (Gd) can be further doped.

6, by the Gd doping, the electrode support 120 includes the first metal oxide 15 doped with gadolinium 50, and the second metal oxide 20 .

As described above, when the preliminary electrode support 100, the cathode 200 and the electrolyte membrane 300 are doped with gadolinium (Gd), the electrode support 120, the cathode 200, and the electrolyte The ion conduction characteristics of the film 300 can be improved.

1 and 2, the preliminary electrode supporting body 100 may be formed of a material having a high thermal conductivity and a high thermal conductivity. In addition, the preliminary electrode supporting body 100 may be doped with gadolinium (Gd) The sintering aids (for example, divalent and trivalent metal oxides) added to and mixed with the first metal oxide 10 and the second metal oxide 20 before the physical mixing are mixed with gadolinium (Gd) and May be doped together with the spare electrode support 100. The sintering auxiliary doped in the preliminary electrode support 100 can improve the ion conduction characteristics of the preliminary electrode support 100 as well as gadolinium (Gd) doped in the preliminary electrode support 100. In addition, since the cost of the sintering agent is lower than that of gadolinium (Gd), the manufacturing cost of the fuel cell manufactured according to the embodiment of the present invention can be reduced.

In addition, the structure of the electrolyte membrane 300 can be dense by the heat treatment, and the interface characteristics between the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 can be improved have. Thus, the energy efficiency of the fuel cell manufactured according to the embodiment of the present invention can be improved.

Unlike the embodiments of the present invention described above, in the case of conventional fuel cells, a negative electrode and an electrolyte membrane are formed on an electrode support manufactured using gadolinium (Gd) -doped cerium oxide, for example, Gd- A battery is manufactured. As described above, when the electrode support is prepared by using the cerium oxide already doped with gadolinium (Gd) and then used for manufacturing a fuel cell, by using the cadmium oxide powder doped with the expensive gadolinium (Gd) The manufacturing cost of the device increases, and there is a limit to the mass production.

However, as described above, according to the embodiment of the present invention, after the preliminary electrode support 100 is manufactured, the preliminary electrode support 100 is immersed in the solution 500 containing gadolinium (Gd) A fuel cell including the electrode support 120 doped with gadolinium (Gd) may be manufactured. As a result, the use of gadolinium (Gd) -doped cerium oxide, which is in the form of expensive powder, is minimized, and the production cost of the fuel cell can be reduced.

After the cathode 200 and the electrolyte membrane 300 are formed on the preliminary electrode support 100, the preliminary electrode support 100, the cathode 200, and the electrolyte membrane 300 Gd is doped into the electrode support 120, the cathode 200 and the electrolyte membrane 300 when the electrolyte is immersed in the solution containing gadolinium (Gd), so that the electrode support 120, The ion conductivity characteristics of the cathode 200 and the electrolyte membrane 300 are improved and the interface characteristics between the electrode support 120, the cathode 200, and the electrolyte membrane 300 are improved A fuel cell having high reliability and high energy efficiency, and a manufacturing method thereof can be provided.

7 is a view for explaining a method of manufacturing a fuel cell according to a first modification of the embodiment of the present invention.

In the method described with reference to Figs. 1 to 3, the spare electrode support 100 can be manufactured. The negative electrode 200 and the electrolyte membrane 300 are not formed on the spare electrode support 100 and the spare electrode support 100 is doped with gadolinium Gd, So that the electrode support 120 can be manufactured. In other words, after the preliminary electrode support 100 is immersed in the solution 500 containing gadolinium (Gd) alone, the preliminary electrode support 100 may be heat-treated to be doped with gadolinium (Gd) have. 4 to 5, the negative electrode 200, the electrolyte membrane 300, and the negative electrode layer 300 are formed on the electrode support 120 manufactured by the method described with reference to FIG. 7, The anode 400 may be formed.

8 is a view for explaining a method of manufacturing a fuel cell according to a second modification of the embodiment of the present invention.

In the method described with reference to Figs. 1 to 4, the spare electrode support 100 and the cathode 200 can be manufactured. 4, the cathode 200 is formed on the preliminary electrode support 100, but the electrolyte membrane 300 is not formed, and the preliminary electrode support 100 and the cathode (not shown) 200 are doped with gadolinium (Gd), so that the electrode support 100 and the cathode 200 doped with gadolinium can be manufactured. In other words, after the cathode 200 is formed on the preliminary electrode support 100, the preliminary electrode support 100 and the cathode 200 are immersed in the solution 500 containing gadolinium (Gd) The preliminary electrode support 100 and the cathode 200 may be doped with gadolinium (Gd). Thereafter, on the cathode 200 further doped with the electrode support 120 and the gadolinium (Gd) produced by the method described with reference to Fig. 8, as described with reference to Figs. 4 to 5, The electrolyte membrane 300 and the anode 400 may be formed.

Hereinafter, a specific experimental example according to the method of manufacturing a fuel cell according to the above-described embodiment of the present invention will be described.

Table 1 below shows the cost component ratio analyzed using the composition ratio of each material of the fuel cell using NiO-GDC as a cathode support and the current material price. NiO-GDC cathode The half-cell with NiO-GDC cathode layer and GDC electrolyte on the anode support is composed of about 95 wt% of NiO-GDC, and the amount of GDC in half cell is more than 47 wt% . At present, the material cost of GDC formed by processing Ceria (CeO ₂ ) powder is about 9 times that of CeO ₂ . When the GDC powder is used for the cathode support, the fraction of the material cost occupied by the GDC of the cathode support is about 78%. However, as shown in Table 1, when the GDC of the cathode support is replaced with CeO ₂ , as in the embodiment of the present invention described above, it is expected that the material cost is reduced by about 1/3 as compared with the case of using GDC do.

Layer Thickness Process GDC / NiO-GDC / NiO-GDC GDC / NiO-GDC / NiO-CeO ₂ Material Wt%  Material cost% Material Wt% Material cost% Electrolyte ~ 20㎛ Dip coating GDC 4.4% 7.3% GDC 4.4% 23.6% Anode functional Layer ~ 20㎛ Dip coating GDC GDC NiO 52.6% 15% NiO 52.6% 48.5% Anode support ~ 700 μm Tape casting NiO NiO GDC 43% 77.7% CeO ₂ 43% 27.8%

The fuel cell fabrication according to the embodiment

A green tape of a NiO-CeO ₂ cathode support was formed by tape casting. Specifically, NiO and CeO ₂ were mixed at a mass ratio of 55:45, using a solvent of ethyl alcohol and toluene as a solvent, and subjected to primary ball milling for 24 hours. Bi-butyl phthalate as a binder and Bi-butyl phthalate as a plasticizer were added to perform ball milling for an additional 24 hours to form a slurry. After the bubbles in the slurry were removed, casting and drying were carried out to obtain a NiO-CeO ₂ anode support green A tape was prepared. The formed green tapes were laminated in three layers using a heat press method to form a desired thickness. The green tape of the laminated NiO-CeO ₂ anode support was heat-treated at a temperature of 900 ° C to ensure mechanical properties for the post-processing. A functional cathode layer and an electrolyte were formed of a colloidal solution on a partially baked NiO-CeO ₂ cathode support and formed by a dip coating method. Specifically, the colloidal solution of the functional cathode layer was prepared by mixing a mixture of NiO and GDC powder in a mass ratio of 50:50 into a mixed solvent of Ethyl alcohol and Terpineol at a constant ratio, and then adding a binder, a plasticizer, and a dispersant, Followed by ball milling. The colloidal solution of the electrolyte was prepared by mixing GDC powder with Ethyl alcohol and Terpineol at a constant ratio, and then adding a binder, a plasticizer, and a dispersant to the solution, and ball milling for 48 hours.

The NiO-CeO ₂ cathode support was immersed in a NiO-GDC colloidal solution and a GDC colloidal solution to form a NiO-GDC functional cathode and a GDC electrolyte membrane sequentially by dip coating. After heat treatment at 900 ° C, it was immersed in a solution of Gd-nitrate dissolved in ethyl alcohol, dried, and sintered at 1450 ° C to form half cells. Screen printing was performed using LSCF-GDC paste as an air electrode on the half cell, followed by heat treatment at a temperature of 1050 ° C to form the fuel cell according to the embodiment.

Production of fuel cell according to Comparative Example

Instead of preparing the anode support using NiO and CeO ₂ , the NiO-GDC cathode support was prepared using NiO and GDC in the same manner as the above-described embodiment.

Thereafter, a NiO-GDC functional cathode and a GDC electrolyte membrane were sequentially formed using a dip coating method in which a NiO-GDC cathode support was immersed in a NiO-GDC colloidal solution and a GDC colloidal solution in the same manner as in the above- . Subsequently, the substrate was partially heat-treated at a temperature of about 900 ° C and then sintered at a temperature of 1450 ° C to form half cells. Screen printing was performed on the half cells using an LSCF-GDC paste as an air electrode at a temperature of 1050 ° C Followed by heat treatment to form a fuel cell according to a comparative example.

9 and 10 are SEM photographs of a cathode support included in a fuel cell according to an embodiment of the present invention. 9 (a) is an SEM photograph of a NiO-CeO ₂ cathode support thermally treated at 900 ° C., and FIG. 9 (b) is a SEM photograph of a NiO-CeO ₂ cathode support on which Gd- SEM image, and FIG. 10 (a) is an SEM photo photographed the heat-treated-CeO ₂ NiO cathode support at 1450 ℃, 10 of (b) is Gd- the NiO-CeO ₂ cathode substrate subjected to heat treatment at 1450 ℃ FIG. 10 (c) is a SEM photograph taken after heat treatment at 1450 ° C. FIG. 10 (c) is a SEM photograph taken after heat treatment at 900 ° C.

9 and 10, the GDC electrolyte annealed at 900 ° C., the NiO-GDC functional cathode layer, and the NiO-CeO ₂ cathode support were immersed in a Gd-nitrate solution and then heat-treated in an oven at 100 ° C. for 3 times And the amount of infiltration in the NiO-CeO ₂ cathode support was calculated. The mass of Gd-nitrate was measured on a 12cm x 12cm substrate heated at 900 ℃, and the mass change was about 0.03 ~ 0.05g. It was assumed that the Gd-nitrate was deposited in a uniform distribution on the substrate , It is expected that an amount of about 50 ppm or less is adsorbed on the CeO ₂ surface in the NiO-CeO ₂ cathode support.

In the case of the anode support heat treated at 1450 ° C, the surface of the particles is very clean. However, as shown in FIG. 10 (b), it was confirmed that the surface of the particles annealed at 900 ° C. after depositing Gd-nitrate showed a rough shape. Gd ₂ O ₃ was formed on the roughened surface by heat treatment at low temperature after Gd-nitrate precipitated on the surface of the particles. It is confirmed that the rough surface is again cleaned by heat treatment at 1450 ° C. It is confirmed that the Gd ₂ O ₃ formed on the surface is doped to the particles of the anode support by the heat treatment .

11 is a graph showing XPS data of a cathode support included in a fuel cell according to an embodiment of the present invention. Specifically, Figs. 11 (a), 11 (b) and 11 (c) show the result of XPS analysis of the negative electrode support of NiO-CeO ₂ heat- (f) shows the results of XPS analysis of the anode support of NiO-CeO ₂ annealed at 1450 ° C after Gd-nitrate infiltration.

Referring to FIG. 11, when the intensity of a peak represented by each component is normalized, it is seen that the peak due to Gd of the Gd infiltrated cathode support is slightly increased compared to the peak due to oxygen or cerium.

12 is a graph showing electrical characteristics of a fuel cell according to Examples and Comparative Examples of the present invention.

12, the negative electrode was measured NiO-CeO ₂ support, Gd-nitrate infiltration is performed a NiO-CeO ₂ cathode support, and IVP with the impedance of a fuel cell comprising a NiO-GDC anode support. A comparison of the one IVP measured at 600 ℃, battery using the Ni-GDC cathode cell with Gd-nitrate infiltration is carried out with Ni-CeO ₂ anode support with the support is shown substantially the same IVP properties, while, Ni-CeO ₂ cathode In the case of the battery using the support, it was confirmed that the IVP characteristics were relatively low. The results of the Impedance, ASR obtained from the electrodes is 0.13 ~ 0.15 Ωcm, but no significant difference in ^two, in the case of the ohmic ASR Ni-CeO ₂ is the battery using the cathode support Ni-GDC anode support cell and Gd-nitrate with it can be confirmed that it is higher than that of the battery using the Ni-CeO ₂ cathode support subjected to the infiltration.

When Gd-nitrate is immersed in a porous GDC electrolyte, a NiO-GDC functional cathode film, and a NiO-CeO ₂ cathode support heat treated at 900 ° C., Gd is deposited on the surface of all the particles of the electrolyte, the functional cathode film, And can affect the sintering property particularly at the portion where the electrolyte and the three-phase region of the functional cathode layer interface are formed. However, the microstructural characteristics of the GDC electrolyte and the NiO-GDC functional cathode membrane are considered to be the same for a cell using NiO-GDC as a cathode support and a cell using NiO-CeO2 as a cathode support without Gd deposition. However, from the result of the impedance, it can be confirmed that the difference in the ohmic ASR of each cell is influenced by the sintering property of the anode support, and that the sintering property of CeO ₂ doped with Gd is superior to that of the cell using CeO ₂ . Therefore, when CeO ₂ doped with GDC or Gd is used as the material of the anode support, shrinkage occurs more in the sintering process, thereby increasing the density of the GDC electrolyte layer, and the OCV (Open Circuit Voltage) this value is looking from the IVP result of 600 ℃ Ni-CeO ₂ than that of the cell using a negative electrode substrate, using the Ni-GDC, and Gd-infiltration Ni-CeO ₂ cathode support cells can be confirmed by showing a high value.

As a result, when Ni-CeO ₂ is used as a negative electrode support, the power generation characteristics are lower than those of a battery using Ni-GDC as an anode support. However, when Ni-CeO ₂ is immersed in Gd- It is confirmed that the power generation characteristics substantially the same as the GDC. Thus, it can be seen that by performing the step of doping Gd-nitrate by using CeO ₂ as a raw material for the anode support, the efficiency of the cell can be improved and the manufacturing cost can be significantly reduced.

FIG. 13 is a view for explaining an example of a fuel cell system for power generation using a fuel cell manufactured according to an embodiment and a modified example of the present invention.

13, the power generation fuel cell system includes a fuel cell 700 manufactured according to an embodiment of the present invention and modifications thereof, and a power control device 800). The power control device 800 may include an output device 810, a power storage device 820, a charge / discharge control device 830, and a system control device 840. The output device 810 may include a power inverter 812.

The power conditioning system (PCS) 812 may be an inverter that converts a direct current from the fuel cell 700 into an alternating current. The charge and discharge control device 830 may store the power from the fuel cell 700 in the power storage device 820 or output the electricity stored in the power storage device 820 to the output device 810 . The system controller 840 may control the output device 810, the power storage device 820, and the charge / discharge control device 830.

As described above, the converted alternating current can be supplied to various AC loads 910 such as an automobile, a home, and the like. Furthermore, the output device 810 may further include a grid connect system 814. The grid connection device 814 can transmit power to the outside through a connection with another power system 920.

As described above, in the fuel cell according to the embodiment of the present invention, gadolinium (Gd) is doped in an electrode support, a cathode, and / or an electrolyte membrane by a solution doping method using a solution containing gadolinium (Gd) (Gd) as well as a metal oxide which is a sintering aid are doped together, it is possible to reduce the manufacturing cost of the fuel cell and improve the ion conduction characteristics. Further, the interfacial characteristics between the electrode support, the cathode, and the electrolyte membrane are improved, and a fuel cell with improved energy efficiency can be provided.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. It will also be appreciated that many modifications and variations will be apparent to those skilled in the art without departing from the scope of the present invention.

10: First metal oxide
15: a first metal oxide doped with gadolinium (Gd)
20: Second metal oxide
30: base combination
50: Gadolinium (Gd)
100: spare electrode support
120: Electrode support
200: cathode
300: electrolyte membrane
400: cathode
500: solution containing gadolinium (Gd)
700: Fuel cell
800: Power control device
810: Output device
812: Power conversion device
814: Grid connection
820: Power storage device
830: charge / discharge control device
840: System control device
910: AC load
920: Other power systems
1000: Fuel cell system for power generation

Claims (13)

Physically mixing the first metal oxide and the second metal oxide to form a base combination;
Fabricating the base combination as a preliminary electrode support in the form of a thin layer; And
And doping the preliminary electrode support with gadolinium (Gd) to produce an electrode support.
The method according to claim 1,
Wherein the first metal oxide comprises a cerium (Ce) oxide,
Wherein the second metal oxide comprises nickel (Ni) oxide.
The method according to claim 1,
Before physically mixing the first metal oxide and the second metal oxide,
Further comprising adding and mixing a sintering aid to the first metal oxide and the second metal oxide.
The method of claim 3,
Wherein the sintering assistant comprises a divalent or trivalent metal oxide.
The method according to claim 1,
The physical mixing of the first metal oxide and the second metal oxide,
A first physical mixing process performed by supplying a solvent and a dispersant to the first metal oxide and the second metal oxide; And
A second physical mixing process is performed by supplying a bonding agent and a plasticizer to the first metal oxide and the second metal oxide on which the first physical mixing process has been performed, Wherein the method comprises the steps of:
The method according to claim 1,
The physical mixing of the first metal oxide and the second metal oxide,
And ball milling the first metal oxide and the second metal oxide.
The method according to claim 1,
Before doping the preliminary electrode support with gadolinium (Gd)
And forming an anode and an electrolyte layer on the preliminary electrode support in this order.
8. The method of claim 7,
After the cathode and the electrolyte membrane are formed on the preliminary electrode support,
Further comprising providing heat and pressure to the preliminary electrode support, the cathode, and the electrolyte membrane.
8. The method of claim 7,
The step of doping the preliminary electrode support with gadolinium (Gd)
Wherein the preliminary electrode support, the cathode, and the electrolyte membrane are immersed in a solution containing gadolinium (Gd).
10. The method of claim 9,
The step of doping the preliminary electrode support with gadolinium (Gd)
Further comprising performing a thermal treatment after immersing the preliminary electrode support, the negative electrode, and the electrolyte membrane in a solution containing gadolinium (Gd).
11. The method of claim 10,
The step of heat-treating the preliminary electrode support, the cathode, and the electrolyte membrane,
Wherein the preliminary electrode support, the cathode, and the electrolyte membrane are doped with gadolinium (Gd).
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