KR20210097585A - Fuel cell and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a method for manufacturing a ceramic complex for a fuel cell, which comprises a step of manufacturing a plurality of cells by forming an electrolyte layer on an anode layer; a step of stacking the cells to make the electrolyte layer of the cells in contact with each other; a step of sintering the stacked cells; and a step of separating the stacked cells. According to the present invention, volatilization of Ba is suppressed to manufacture ceramic materials having large crystal grains.

Description

Fuel cell and manufacturing method thereof

The present application relates to a fuel cell and a method for manufacturing the same.

A fuel cell is a cell that converts chemical energy of fuel into electrical energy, and is divided into several types depending on the electrolyte. Among them, the solid oxide fuel cell, which has the highest theoretical efficiency and can use various fuels, is in the spotlight as a next-generation energy conversion system, and an oxygen ion conductor has been mainly used as an electrolyte material. Recently, a fuel cell using a proton conductive electrolyte, which uses a hydrogen ion conductive oxide as an electrolyte, which improves durability of a solid oxide fuel cell by lowering the operating temperature, is attracting attention.

Proton conductive electrolytes can be divided into ceramic series and polymer series. Polymer series is relatively easy to produce but has a low operable temperature range, and ceramic series has a wide operable temperature range but is difficult to produce.

A fuel cell using a proton conductive ceramic electrolyte can theoretically have high ionic conductivity and low activation energy compared to a fuel cell using an oxygen ion conductive ceramic electrolyte, resulting in low Ohmic resistance and a temperature of 500°C to 650°C. It is expected to have a high power density even in the temperature range. However, Ba-based materials mainly used as proton conductive ceramic electrolytes (BaZr _0.85 Y _0.15 O _3-d , BaZr _0.1 Ce _0.7 Y _0.2 O _3-d , BaZr _0.4 Ce _0.4 Y _0.1 -Yb _0.1 O _3-d ) Crystal grain growth is not smooth due to the low sintering property, and the grain boundaries formed in large quantities due to the low degree of grain growth have low ion conductivity, which may undermine the advantages of the proton conductive ceramic electrolyte.

Korean Patent Publication No. 10-1680626, which is the background technology of the present application, relates to a proton conductive oxide fuel cell and a method for manufacturing the same. The registered patent relates to a proton conductive oxide fuel cell, which uses Ba-based ceramic materials such as BZY, BCY, BCZY, and BZCYYb as an electrolyte, but is only for forming dense grains while lowering the sintering temperature of the ceramic material However, the method to fundamentally suppress the volatilization of Ba is not recognized.

An object of the present application is to provide a method for manufacturing a ceramic composite for a fuel cell, and a method for manufacturing a fuel cell including the method for manufacturing a ceramic composite for a fuel cell, in order to solve the problems of the prior art.

Another object of the present application is to provide a fuel cell by the method for manufacturing the fuel cell.

However, the technical problems to be achieved by the embodiments of the present application are not limited to the technical problems as described above, and other technical problems may exist.

As a technical means for achieving the above technical problem, the first aspect of the present application is to form an electrolyte layer on an anode layer to manufacture a plurality of cells, stacking the cells so that the electrolyte layer of the cells abuts , sintering the stacked cells, and providing a method of manufacturing a ceramic composite for a fuel cell comprising the steps of separating the stacked cells.

According to one embodiment of the present application, the electrolyte layer may include Ba, but is not limited thereto.

According to one embodiment of the present application, the electrolyte layer contains an element selected from the group consisting of Zr, Ce, Y, Yb, Pr, Pd, Sr, Co, Fe, Mn, Ni, Cu, Zn, and combinations thereof. It may further include, but is not limited thereto.

According to one embodiment of the present application, the atomic ratio of Ba and Zr of the electrolyte of the ceramic composite for a fuel cell may be 2.0 to 2.5, but is not limited thereto.

According to the exemplary embodiment of the present application, the sintering may be performed at 1,000° C. to 1,800° C., but is not limited thereto.

According to the exemplary embodiment of the present application, the size of the crystal grains of the electrolyte of the ceramic composite for a fuel cell may be 3 μm to 8 μm, but is not limited thereto.

According to one embodiment of the present application, the step of forming the electrolyte layer is spin coating, sol-gel, spray coating, drop casting, inkjet printing, screen printing, doctor blade, dip coating, roll-to- It may be carried out by a process comprising one selected from the group consisting of roll-to-roll and combinations thereof, but is not limited thereto.

According to the exemplary embodiment of the present application, the anode layer may include, but is not limited to, a material selected from the group consisting of Ni, Zr, Y, Ba, Ce, Yb, and combinations thereof.

In addition, a second aspect of the present application provides a method for manufacturing a fuel cell, further comprising the step of forming a cathode layer on the electrolyte layer of the ceramic composite for a fuel cell manufactured by the first aspect.

In addition, a third aspect of the present application is the fuel cell manufactured by the second aspect, comprising an anode electrode, a proton conductive electrolyte formed on the anode electrode, and a cathode electrode formed on the proton conductive electrolyte, A fuel cell is provided.

According to one embodiment of the present application, the proton conductivity of the proton conductive electrolyte may be 1×10 ⁻³ Ω ⁻¹ cm ⁻¹ to 5×10 ⁻² Ω ⁻¹ cm ⁻¹ , but is not limited thereto.

According to one embodiment of the present application, the cathode electrode may include a material selected from the group consisting of Pt, Ag, Pd, Au, La, Sr, Mn, Ni, Al, Cr, oxides thereof, and combinations thereof. However, the present invention is not limited thereto.

According to the exemplary embodiment of the present application, the ion conduction activation energy of the fuel cell may be 0.45 eV to 0.47 eV, but is not limited thereto.

According to the exemplary embodiment of the present application, the area specific impedance of the fuel cell may be 0.2 Ωcm ² to 0.4 Ωcm ² , but is not limited thereto.

According to the exemplary embodiment of the present application, the power density of the fuel cell may be 0.6 W/cm ² to 0.7 W/cm ² , but is not limited thereto.

The above-described problem solving means are merely exemplary, and should not be construed as limiting the present application. In addition to the exemplary embodiments described above, additional embodiments may exist in the drawings and detailed description.

According to the means for solving the above problems, the fuel cell and the method for manufacturing the same according to the present application suppress the volatilization of Ba, which suppresses the growth of crystal grains in the proton conductive ceramic electrolyte, compared to the conventional fuel cell and method for manufacturing the same. Ceramic materials with larger grains can be produced.

In addition, an electrolyte having an ion conduction activation energy of 0.49 eV can be prepared with the conventional fuel cell and its manufacturing method. It is possible to form a proton conductive ceramic electrolyte having an ion conduction activation energy. The ion conduction activation energy of the proton conductive ceramic electrolyte according to the present application is closer to the theoretical value compared to the ion conduction activation energy of the conventional ceramic electrolyte, which means that the proton conductive ceramic electrolyte according to the present application has better performance than the conventional proton conductive ceramic electrolyte means to have

In addition, the proton conductive ceramic electrolyte prepared according to the fuel cell and the manufacturing method thereof according to the present application has a 20% higher maximum power density and 20% lower ohmic resistance reduction compared to a conventional proton conductive ceramic electrolyte when electrochemically driven at 650°C can be implemented.

However, the effects obtainable herein are not limited to the above-described effects, and other effects may exist.

1 is a flowchart of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application.
2 is a schematic diagram of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application.
3 is a schematic diagram of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application.
4 is a schematic diagram of a conventional method for manufacturing a ceramic composite for a fuel cell.
Figure 5 (a) is a photograph showing a protective sintering method, according to an embodiment of the present application, (b) is a SEM image of the electrolyte according to the embodiment.
6 (a) is a photograph showing a conventional sintering method according to a comparative example of the present application, and (b) is a SEM image of the electrolyte according to the comparative example.
7 (a) is an XRD pattern of an electrolyte according to an embodiment of the present application, (b) is an XRD pattern of an electrolyte according to a comparative example of the present application.
8 is a graph showing the volatility of Ba of the electrolyte according to an embodiment and a comparative example of the present application.
9 is a graph illustrating electrochemical performance of fuel cells according to Examples and Comparative Examples of the present application.
10 is an impedance diagram of a fuel cell according to an embodiment and a comparative example of the present application.
11 is an Arrhenius diagram of a fuel cell according to an embodiment and a comparative example of the present application.

Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present application pertains can easily implement them.

However, the present application may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present application in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout this specification, when a part is said to be "connected" with another part, it includes not only the case where it is "directly connected" but also the case where it is "electrically connected" with another element interposed therebetween. do.

Throughout this specification, when it is said that a member is positioned "on", "on", "on", "under", "under", or "under" another member, this means that a member is positioned on the other member. It includes not only the case where they are in contact, but also the case where another member exists between two members.

Throughout this specification, when a part "includes" a component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

As used herein, the terms "about," "substantially," and the like are used in a sense at or close to the numerical value when the manufacturing and material tolerances inherent in the stated meaning are presented, and to aid in the understanding of the present application. It is used to prevent an unconscionable infringer from using the mentioned disclosure in an unreasonable manner. Also, throughout this specification, "step to" or "step to" does not mean "step for".

Throughout this specification, the term "combination of these" included in the expression of the Markush form means one or more mixtures or combinations selected from the group consisting of the components described in the expression of the Markush form, and the components It is meant to include one or more selected from the group consisting of.

Throughout this specification, reference to “A and/or B” means “A or B, or A and B”.

Hereinafter, a fuel cell and a method for manufacturing the same of the present application will be described in detail with reference to embodiments, examples, and drawings. However, the present application is not limited to these embodiments and examples and drawings.

As a technical means for achieving the above technical task, the first aspect of the present application is to form an electrolyte layer 200 on the anode layer 100 to prepare a plurality of cells (not shown), the electrolyte of the cells It provides a method of manufacturing a ceramic composite for a fuel cell (not shown), comprising stacking the cells so that the layers 200 come into contact with each other, sintering the stacked cells, and separating the stacked cells. .

In general, in a fuel cell, hydrogen ions supplied from a cathode move to an anode through an electrolyte, and the hydrogen ions react with oxygen in the anode to generate electricity through a water-generating reaction. . In this regard, if the electrolyte is a solid, it may be referred to as a solid electrolyte fuel cell, and the solid electrolyte may be classified into a ceramic series and a polymer series depending on the material, and hydrogen ions (H ⁺ , protons) , proton) conductivity or oxygen ion (O ^{2 -} ) conductivity.

In this regard, the electrolyte layer 200 of the ceramic composite for a fuel cell may include a proton conductive ceramic electrolyte for moving protons between the anode layer 100 and a cathode layer (not shown) to be described later, Hereinafter, unless otherwise specified, the proton conductive electrolyte means a proton conductive ceramic electrolyte.

The proton conductive ceramic electrolyte according to the present disclosure refers to an electrolyte made of a ceramic material capable of conducting ^{protons, that is, H + ions.} In general, since proton conductive ceramic electrolytes have theoretically high ionic conductivity (proton conductivity) and low activation energy compared to oxygen ion conductive ceramic electrolytes, protonic ceramic fuel cells (PCFCs) have low ionic conduction resistance. It was expected to show high power density even in the temperature range of 500°C to 700°C.

However, in the case of a conventional proton conductive ceramic electrolyte containing Ba, since Ba is volatilized during the manufacturing process and the atomic composition ratio inside the electrolyte is collapsed, the sinterability is low, so the growth of crystal grains does not occur even when heat is applied, and grain boundaries ) are many There are disadvantages in that ion conductivity is lowered and activation energy is increased due to the plurality of grain boundaries.

In addition, in order to overcome the conventional method of manufacturing a proton conductive ceramic electrolyte, a plasticizer such as Ni, Cu, or Zn was added to the Ba-based electrolyte to increase the growth of crystal grains, but the added plasticizer was used in the conventional proton conductive ceramic electrolyte There is a problem in that the output density is lowered by lowering the open circuit voltage, and an unintended phase is formed by reacting with other elements of the conventional proton conductive ceramic electrolyte.

The present application provides a method for improving the quality of the Ba-based proton conductive ceramic electrolyte.

1 is a flowchart of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application.

First, the electrolyte layer 200 is formed on the anode layer 100 to manufacture a plurality of cells (S100).

According to one embodiment of the present application, the step of forming the electrolyte layer 200 is spin coating, sol-gel, spray coating, drop casting, inkjet printing, screen printing, doctor blade, dip coating, roll -To-roll (roll-to-roll) and may be performed by a process including one selected from the group consisting of combinations thereof, but is not limited thereto.

According to the exemplary embodiment of the present application, the anode layer 100 may include a material selected from the group consisting of Ni, Zr, Y, Ba, Ce, Yb, and combinations thereof, but is not limited thereto. For example, the anode layer 100 may include a Ni-BZCYYb material, but is not limited thereto.

The anode layer 100 may have a cermet shape, but is not limited thereto. A cermet according to the present application means a composite of metal and ceramic.

According to one embodiment of the present application, the electrolyte layer 200 may include Ba, but is not limited thereto.

According to one embodiment of the present application, the electrolyte layer 200 is from the group consisting of Zr, Ce, Y, Yb, Pr, Pd, Sr, Co, Fe, Mn, Ni, Cu, Zn, and combinations thereof. It may further include a selected element, but is not limited thereto.

For example, the electrolyte layer 200 is BaZr _a Ce _b Y _c Yb _d O _3-δ (provided that a+b+c+d=1, a is greater than 0 and less than 1, b, c, and d is greater than or equal to 0 and less than 1), BaCeO ₃ , Y-doped BaCeO _3-δ , Yb-doped BaCeO _3-δ , PrBa _0.5 Sr _0.5 Co _1.5 Fe _0.5 O _5+δ , Ba _0.5 Sr _0.5 Co _0.8 Fe _0.2 O It may include, but is not limited to, those selected from the group consisting of _{3-δ , and combinations thereof.}

In this regard, the electrolyte layer 200 may include oxygen vacancies. Among the materials presented as examples of the electrolyte layer 200, δ means the amount of oxygen changed while the oxygen vacancy is formed, and d may be used instead of δ.

_{In addition, BZCYYb (BaZr a} Ce _b Y _c Yb _d O _3-δ ) of the electrolyte layer 200 and BZCYYb of the anode layer 100 may have the same or different compositions.

Ba included in the electrolyte layer 200 is to promote the growth of crystal grains, and in the conventional method of manufacturing a ceramic composite for a fuel cell, heat treatment is performed without a protective layer after forming the electrolyte layer, so that a portion of the Ba is volatilized. Thus, the growth of crystal grains is suppressed, and thus a plurality of crystal nuclei are generated, and the size of the crystal grains is formed small by the plurality of crystal nuclei.

However, in the method of manufacturing the ceramic composite for a fuel cell according to the present disclosure, since the electrolyte layer 200 is sintered through a process to be described later, crystal grains having a large size can be formed by suppressing volatilization of Ba.

In this regard, the cell may include, instead of the anode layer 100 , a cathode layer (not shown) to be described later and an electrolyte layer 200 formed on the cathode layer. That is, the ceramic composite for a fuel cell is prepared by manufacturing a plurality of cells composed of the cathode layer/the electrolyte layer 200 or the anode layer 100/the electrolyte layer 200, and then performing the processes to be described later. through the ceramic composite or fuel cell for the fuel cell.

Herein, a method of manufacturing the ceramic composite for a fuel cell through a cell including the anode layer 100 and the electrolyte layer 200 has been disclosed, but the material of the cathode layer is used instead of the material of the anode layer 100 . Thus, a ceramic composite for a fuel cell can be manufactured.

Then, the cells are stacked so that the electrolyte layers 200 of the cells are in contact (S200).

2 is a schematic diagram of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application, and is a schematic diagram of the laminating step in detail.

Since the stacked cells are separable, it is necessary to separate the cells after stacking the electrolyte layers 200 in contact with each other. Accordingly, the cell at the bottom is expressed as a first cell (not shown) including the first anode layer 110 and the first electrolyte layer 210, and the cell at the top is the second anode layer 120 and the second electrolyte. It may be represented as a second cell (not shown) including the layer 220 .

Hereinafter, unless otherwise specified, the first anode layer 110 and the second anode layer 120 may also be expressed as the anode layer 100 , and the first electrolyte layer 210 and the first anode layer 120 . 2 The electrolyte layer 220 may also be expressed as the electrolyte layer 200 .

According to one embodiment of the present application, the stacked cells are the structure of the first anode layer 110 / the first electrolyte layer 210 / the second electrolyte layer 220 / the second anode layer 120 may have, but is not limited thereto. In this regard, the material composition of the first anode layer 110 and the second anode layer 120 is the same, and the material composition of the first electrolyte layer 210 and the second electrolyte layer 220 is the same do.

Then, the stacked cells are sintered (S300).

According to the exemplary embodiment of the present application, the sintering may be performed at 1,000° C. to 1,800° C., but is not limited thereto. For example, the sintering step is from about 1,000 °C to about 1,800 °C, from about 1,100 °C to about 1,800 °C, from about 1,200 °C to about 1,800 °C, from about 1,300 °C to about 1,800 °C, from about 1,400 °C to about 1,800 °C, about 1,500°C to about 1800°C, about 1,600°C to about 1,800°C, about 1,700°C to about 1,800°C, about 1,000°C to about 1,100°C, about 1,000°C to about 1,200°C, about 1,000°C to about 1,300°C, about 1,000°C to about 1,400°C, from about 1,000°C to about 1,500°C, from about 1,000°C to about 1,600°C, from about 1,000°C to about 1,700°C, from about 1,100°C to about 1,700°C, from about 1,200°C to about 1,600°C, from about 1,300°C to about It may be carried out at 1,500 °C, or about 1,400 °C, but is not limited thereto.

3 is a schematic diagram of a method of manufacturing a ceramic composite for a fuel cell according to an embodiment of the present application, and FIG. 4 is a schematic diagram of a method of manufacturing a ceramic composite for a fuel cell according to the related art.

3 and 4 , since the sintering of the method for manufacturing the ceramic composite for a fuel cell according to the present disclosure is performed after the cells are stacked, the volatilization of Ba may be suppressed. Specifically, Ba of the first electrolyte layer 210 moves to the second electrolyte layer 220 even when volatilized, and Ba of the second electrolyte layer 220 moves to the first electrolyte layer 210 . Therefore, the amount of Ba volatilized into the atmosphere is small compared to the conventional method of manufacturing the ceramic composite for fuel cell as shown in FIG. 4 .

Therefore, since the method for manufacturing the ceramic composite for a fuel cell according to the present application suppresses volatilization of Ba, which suppresses the generation of crystal nuclei, the sintered electrolyte layer 200 includes a plurality of Ba, and the Crystal grains of the sintered electrolyte layer 200 may grow.

In this regard, even if the sintering process proceeds, a reaction does not occur between the anode layer 100 and the electrolyte layer 200 . As will be described later, the anode layer 100 and the electrolyte layer 200 may be easily separated.

Next, the stacked cells are separated ( S400 ) to prepare the ceramic composite for the fuel cell.

As described above, the step (S200) of stacking the cells is not a step of adhering the cells so that they are not separated, but stacking the cells so that they are separated. can

In this regard, since the ceramic composite for a fuel cell may have a low flatness of the surface of the electrolyte layer 200 , the method for manufacturing the ceramic composite for a fuel cell according to the present disclosure may be performed after the step of separating the stacked cells. The method may further include processing the surface of the electrolyte layer 200 .

According to the exemplary embodiment of the present application, the ceramic composite for a fuel cell includes a proton conductive electrolyte (not shown) formed by sintering the electrolyte layer 200 , and an anode electrode (not shown) including the anode layer 100 or the The cathode electrode (not shown) including a cathode layer (not shown) may be included, but is not limited thereto. In this regard, when the ceramic composite for a fuel cell includes all of the proton conductive electrolyte, the anode, and the cathode, the ceramic composite for a fuel cell may be used as a fuel cell.

According to one embodiment of the present application, the atomic ratio of Ba and Zr of the electrolyte of the ceramic composite for a fuel cell may be 2.0 to 2.5, but is not limited thereto. For example, the atomic ratio of Ba and Zr of the electrolyte of the ceramic composite for a fuel cell is about 2.0 to about 2.5, about 2.1 to about 2.5, about 2.2 to about 2.5, about 2.3 to about 2.5, about 2.4 to about 2.5, about 2.0 to about 2.1, about 2.0 to about 2.2, about 2.0 to about 2.3, about 2.0 to about 2.4, about 2.1 to about 2.4, or about 2.2 to about 2.3, but is not limited thereto.

As described above, when the electrolyte layer 200 is sintered to prepare a ceramic composite for a fuel cell, volatilization of Ba may be present. As will be described later, the atomic ratio of Ba and Zr of the proton conductive electrolyte prepared by the method for manufacturing a ceramic composite for a fuel cell according to the present application is 2.0 to 2.5, so that the generation of new crystal grains is suppressed and the size of the existing crystal grains can be expanded. . However, since the atomic ratio of Ba and Zr decreases to less than 2.0 when the temperature of the proton conductive electrolyte prepared by the conventional method for manufacturing a ceramic composite for a fuel cell is increased during sintering, the size of the crystal grains of the sintered electrolyte layer 200 is may be formed small.

According to the exemplary embodiment of the present application, the size of the crystal grains of the electrolyte of the ceramic composite for a fuel cell may be 3 μm to 8 μm, but is not limited thereto. For example, the size of the grains of the electrolyte is about 5 μm to about 8 μm, about 6 μm to about 8 μm, about 7 μm to about 8 μm, about 5 μm to about 6 μm, about 5 μm to about 7 μm , or about 6 μm to about 7 μm, but is not limited thereto.

In summary, in the method for manufacturing the ceramic composite for a fuel cell according to the present application, since the plurality of electrolyte layers 200 having the same material composition are brought into contact with each other and then sintered, Ba in the electrolyte layer 200 is To prepare the proton conductive electrolyte while minimizing the volatilization of A method of manufacturing such a fuel cell ceramic composite may be referred to as a protective sintering method.

According to one embodiment of the present application, the method of manufacturing the ceramic composite for a fuel cell may further include forming a first separator (not shown) between the anode layer 100 and the electrolyte layer 200, However, the present invention is not limited thereto.

In addition, the second aspect of the present application provides a method of manufacturing a fuel cell, further comprising the step of forming a cathode layer on the electrolyte layer 200 of the ceramic composite for a fuel cell manufactured by the first aspect.

With respect to the method of manufacturing a fuel cell according to the second aspect of the present application, detailed descriptions of parts overlapping with the first aspect of the present application are omitted, but even if the description is omitted, the contents described in the first aspect of the present application The same can be applied to both sides.

According to the exemplary embodiment of the present application, the method of manufacturing the fuel cell may further include forming a second separator (not shown) between the anode layer 100 and the electrolyte layer 200 , but is limited thereto. it's not going to be

The separator according to the present application means to limit the type of ions moving from the cathode layer or the anode layer 100 to the electrolyte layer 200 . For example, the first separator or the second separator allows protons to pass through but not oxygen ions, so that the electrolyte layer 200 transfers the protons from the anode layer 100 to the cathode layer or the cathode. It may be moved from the layer to the anode layer 100, but is not limited thereto.

In this regard, when the electrolyte layer 200 is replaced with an oxygen ion conductive electrolyte, the first separator or the second separator may pass the oxygen ions but not the protons, but is not limited thereto. .

In addition, a third aspect of the present application is the fuel cell manufactured by the second aspect, comprising an anode electrode, a proton conductive electrolyte formed on the anode electrode, and a cathode electrode formed on the proton conductive electrolyte, A fuel cell is provided.

With respect to the fuel cell according to the third aspect of the present application, detailed descriptions of parts overlapping with the first and/or second aspects of the present application are omitted, but even if the description is omitted, the first and/or second aspects of the present application are omitted. The contents described in the second aspect may be equally applied to the third aspect of the present application.

In general, a fuel cell using a solid electrolyte has a disadvantage in that it operates at a high temperature of 700°C to 1,000°C in order to increase the ionic conductivity of the solid electrolyte, but has a simpler structure than other fuel cells and uses waste heat to There are advantages that can be further developed.

The photon conductive electrolyte is formed by protectively sintering the electrolyte layer 200 of the first side, the anode layer 100 of the first side means the anode electrode, and the cathode layer of the second side is the means the cathode electrode.

An oxidation reaction occurs in the anode electrode to convert hydrogen molecules into protons, and the protons move to the cathode electrode through the proton conductive electrolyte, so that the fuel cell can generate electricity.

Since the proton conductive electrolyte is a ceramic material, unlike a general liquid electrolyte, the higher the temperature, the higher the ionic conductivity. In this regard, the proton (H ⁺ ) may move from the anode electrode to the cathode electrode or from the cathode electrode to the anode electrode by bonding and separation from the ^{O −} group in the proton conductive electrolyte.

According to one embodiment of the present application, the proton conductivity of the proton conductive electrolyte may be 1×10 ⁻³ Ω ⁻¹ cm ⁻¹ to 5×10 ⁻² Ω ⁻¹ cm ⁻¹ , but is not limited thereto.

For example, the proton conductive electrolyte is about 0.001 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.002 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.003 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.004 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.005 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.006 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^{-1 to} about 0.007 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.008 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.009 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.01 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.015 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.02 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.025 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.03 Ω ^-1 cm ^{- 1} to about 0.05 Ω ^-1 cm ^-1 , about 0.035 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.04 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.045 Ω ^-1 cm ^-1 to about 0.05 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.002 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.003 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.004 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.005 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.006 Ω ^{- 1} cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.007 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.008 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.009 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.01 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.015 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.02 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.025 Ω ^{- 1} cm ^{-1 to} about 0.001 Ω ^-1 cm ^-1 to about 0.03 Ω ^-1 cm ^{-1 to} about 0.001 Ω ^-1 cm ^-1 to about 0.035 Ω ^-1 cm ^{-1 to} about 0.001 Ω ^-1 cm ^-1 to About 0.04 Ω ^-1 cm ^-1 , about 0.001 Ω ^-1 cm ^-1 to about 0.045 Ω ^-1 cm ^-1 , about 0.002 Ω ^-1 cm ^-1 to about 0.045 Ω ^-1 cm ^-1 , about 0.003 Ω ^-1 cm ^-1 to about 0.04 Ω ^-1 cm ^-1 , about 0.004 Ω ^-1 cm ^-1 to about 0.035 Ω ^-1 cm ^-1 , about 0.005 Ω ^-1 cm ^-1 to about 0.03 Ω ^-1 cm ^-1 , about 0.006 Ω ^-1 cm ^-1 to about 0.025 Ω ^-1 cm ^-1 , about 0.007 Ω ^-1 cm ^-1 to about 0.02 Ω ^-1 cm ^-1 , about 0.008 Ω ^-1 cm ^-1 to about 0.015 Ω ^-1 cm ^-1 , or about 0.009 Ω ^-1 cm ^-1 to about 0.01 Ω ^-1 cm ^-1 , but is not limited thereto.

In this regard, when the temperature of the proton conductive electrolyte increases, the proton conductivity may also increase.

For example, the proton conductivity of the proton conductive electrolyte ^{may be 3.5×10 -2} Ω ^-1 cm ^-1 at 650° C., and 6×10 ^-3 Ω ^-1 cm ^-1 at 400° C., but limited thereto it's not going to be

According to the exemplary embodiment of the present application, the ion conduction activation energy of the fuel cell may be 0.45 eV to 0.47 eV, but is not limited thereto. For example, the ion conduction activation energy may be about 0.45 eV to about 0.47 eV, about 0.46 eV to about 0.47 eV, or about 0.45 eV to about 0.46 eV, but is not limited thereto.

The ion conduction activation energy according to the present disclosure may be affected by the size of the grains of the proton conductive electrolyte. Specifically, in the conventional proton conductive electrolyte, a large number of grains are generated by the volatilization of Ba, and the average size of the grains is small, so that the ion conduction activation energy is high. However, since the proton conductive electrolyte prepared by the protective sintering method of the present application has a large average grain size, it may have a value similar to the theoretical value (˜0.45 eV) of the ion conduction activation energy of the proton conductive electrolyte.

According to the exemplary embodiment of the present application, the area specific impedance of the fuel cell may be 0.2 Ωcm ² to 0.4 Ωcm ² , but is not limited thereto.

As described above, since the size of the crystal grains of the electrolyte layer 200 is large, the ion conduction activation energy is reduced compared to the conventional proton conducting electrolyte, and accordingly, the ion conduction impedance and the area specific impedance are also reduced.

According to the exemplary embodiment of the present application, the power density of the fuel cell may be 0.6 W/cm ² to 0.7 W/cm ² , but is not limited thereto.

According to the exemplary embodiment of the present application, the fuel cell may be electrochemically driven at 600° C. to 800° C., but is not limited thereto. For example, the fuel cell may be from about 600°C to about 800°C, from about 650°C to about 800°C, from about 700°C to about 800°C, from about 750°C to about 800°C, from about 600°C to about 650°C, about 600 ℃ to about 700 ℃, about 600 ℃ to about 750 ℃, about 650 ℃ to about 750 ℃, or may be driven at about 700 ℃, but is not limited thereto.

The fuel cell including the proton conductive electrolyte can be electrochemically driven at 650° C., and when electrochemically driven, the area specific impedance of the fuel cell is about 0.2 Ωcm ² to about 0.4 Ωcm ² , about 0.3 Ωcm ² to about 0.4 Ωcm ² , or about 0.2 Ωcm ² to about 0.3 Ωcm ² , and a power density of about 0.6 W/cm ² to about 0.7 W/cm ² , about 0.6 W/cm ² to about 0.65 W/cm ² , or about 0.65 W/cm 2 , cm ² to about 0.7 W/cm ² It may be, but is not limited thereto.

According to one embodiment of the present application, the cathode electrode may include a material selected from the group consisting of Pt, Ag, Pd, Au, La, Sr, Mn, Ni, Al, Cr, oxides thereof, and combinations thereof. However, the present invention is not limited thereto.

The present invention will be described in more detail through the following examples, but the following examples are for illustrative purposes only and are not intended to limit the scope of the present application.

[Example]

To have the Ni-BZCYYb thickness of 20 μm on the cermet substrate produced by dry compression molding electrolyte _{BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1} O a _3-d the deposition by spin coating _{method, Ni-BZCYYb / BaZr 0.1 Ce} 0.7 Y 0.1 Two Yb _0.1 O _3-d cells were prepared. Then, the electrolyte portions of the two cells were combined so as to be in contact with each other, and sintered at 1500° C. for 3 hours. Then, the two sintered cells were separated, and a PrBa _0.5 Sr _0.5 Co _1.5 Fe _0.5 O _5+d positive electrode was screen-printed on the _{sintered, Ni-BZCYYb/BaZr 0.1} Ce _0.7 Y _0.1 Yb _0.1 O _{3-d to form Ni} A fuel cell having a -BZCYYb/BZCYYb/PBSCF structure was prepared.

Figure 5 (a) is a photograph showing the protective sintering method according to the embodiment, (b) is a SEM image of the electrolyte according to the embodiment.

Referring to FIG. 5 , it can be seen that the cell prepared by the protective sintering method has a grain size of 4 μm to 7 μm.

[Comparative example]

A Ni-BZCYYb/BaZr _0.1 Ce _0.7 Y _0.1 Yb _0.1 O _3-d cell was prepared in the same manner as in Example. Then, _{after sintering the BaZr 0.1} Ce _0.7 Y _0.1 Yb _0.1 O _3-d at 1,500° C. for 3 hours, PrBa _0.5 Sr _0.5 Co _1.5 Fe _0.5 O on _{the BaZr 0.1} Ce _0.7 Y _0.1 Yb _0.1 O _{3-d top The 5+d} anode was screen printed.

Figure 6 (a) is a photograph showing a conventional sintering method according to the comparative example, (b) is a SEM image of the electrolyte according to the comparative example.

5 and 6, it was confirmed that the crystal grains of the proton conductive ceramic electrolyte prepared by the conventional sintering method have an average size smaller than the crystal grains of the proton conductive ceramic electrolyte prepared by the protective sintering method.

[Experimental Example 1]

7 (a) is an XRD pattern of the electrolyte according to the embodiment, (b) is an XRD pattern of the electrolyte formed according to the comparative example, and FIG. is a graph showing

7 and 8 , in the proton conductive ceramic electrolyte prepared by the method according to the embodiment, the volatilization of Ba was supplemented and a separate phase did not appear, and the Ba/Zr ratio was maintained to be close to 2.5, but the In the proton conductive ceramic electrolyte prepared by the method according to Comparative Example, a separate phase was generated by volatilization of Ba, and it can be seen that the Ba/Zr ratio decreases as the sintering temperature increases.

[Experimental Example 2]

9 is a graph showing the electrochemical performance of the fuel cell according to the Example and Comparative Example, FIG. 10 is an impedance diagram of the fuel cell according to the Example and Comparative Example, and FIG. 11 is the Example and Comparative Example It is an Arrhenius diagram of the fuel cell according to

9 , a graph having a shape of a linear function with respect to current density (x-axis) is a graph between current density and voltage (left y-axis of the graph), and a graph having a shape of a quadratic function with respect to current density is a graph between current density and power density (right y-axis of the graph).

9 to 11 , the maximum power density of the fuel cell according to the embodiment is 0.654 W/cm ² , and the ion conduction activation energy is 0.462 eV, but the fuel cell according to the comparative example has a maximum power density of 0.538 W/cm ² , and the ion conduction activation energy was found to be 0.494 eV. In addition, it can be seen that the ohmic resistance of the fuel cell according to the embodiment is reduced by 20% compared to the ohmic resistance of the fuel cell according to the comparative example. Therefore, it can be confirmed that the fuel cell according to the embodiment has better performance than the fuel cell according to the comparative example.

The foregoing description of the present application is for illustration, and those of ordinary skill in the art to which the present application pertains will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and likewise components described as distributed may be implemented in a combined form.

The scope of the present application is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present application.

100: anode layer
110: first anode layer
120: second anode layer
200: electrolyte layer
210: first electrolyte layer
220: second electrolyte layer

Claims (15)

manufacturing a plurality of cells by forming an electrolyte layer on the anode layer;
stacking the cells so that the electrolyte layers of the cells abut;
sintering the stacked cells; and
separating the stacked cells;
containing,
A method of manufacturing a ceramic composite for a fuel cell.
The method of claim 1,
The electrolyte layer is a method of manufacturing a ceramic composite for a fuel cell comprising Ba.
3. The method of claim 2,
The electrolyte layer further comprises an element selected from the group consisting of Zr, Ce, Y, Yb, Pr, Pd, Sr, Co, Fe, Mn, Ni, Cu, Zn, and combinations thereof, ceramic composite for fuel cell manufacturing method.
4. The method of claim 3,
The atomic ratio of Ba and Zr of the electrolyte of the ceramic composite for a fuel cell is 2.0 to 2.5, the method of manufacturing a ceramic composite for a fuel cell.
The method of claim 1,
The sintering step is a method of manufacturing a ceramic composite for a fuel cell that is performed at 1,000 ℃ to 1,800 ℃.
The method of claim 1,
The crystal grain size of the electrolyte of the ceramic composite for a fuel cell is 3 μm to 8 μm, a method of manufacturing a ceramic composite for a fuel cell.
The method of claim 1,
The step of forming the electrolyte layer is spin coating, sol-gel, spray coating, drop casting, inkjet printing, screen printing, doctor blade, dip coating, roll-to-roll) and a method for manufacturing a ceramic composite for a fuel cell, which is performed by a process comprising one selected from the group consisting of combinations thereof.
The method of claim 1,
Wherein the anode layer is selected from the group consisting of Ni, Zr, Y, Ba, Ce, Yb, and combinations thereof.
The method according to any one of claims 1 to 8, further comprising the step of forming a cathode layer on the electrolyte layer of the ceramic composite for fuel cell,
A method for manufacturing a fuel cell.
10. A fuel cell manufactured by the method according to claim 9, comprising:
anode electrode;
a proton conductive electrolyte formed on the anode electrode; and
a cathode electrode formed on the proton conductive electrolyte;
which includes,
fuel cell.
11. The method of claim 10,
The proton conductivity of the proton conductive electrolyte is 1×10 ⁻³ Ω ⁻¹ cm ⁻¹ to 5×10 ⁻² Ω ⁻¹ cm ⁻¹ , a fuel cell.
11. The method of claim 10,
and the cathode electrode is selected from the group consisting of Pt, Ag, Pd, Au, La, Sr, Mn, Ni, Al, Cr, oxides thereof, and combinations thereof.
11. The method of claim 10,
An ion conduction activation energy of the fuel cell is 0.45 eV to 0.47 eV.
11. The method of claim 10,
The area specific impedance of the fuel cell is 0.2 Ωcm ² to 0.4 Ωcm ² , the fuel cell.
11. The method of claim 10,
The power density of the fuel cell is 0.6 W/cm ² to 0.7 W/cm ² , the fuel cell.

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