KR102110672B1 - Solid oxide fuel cell and battery module - Google Patents

Abstract

The present specification relates to a solid oxide fuel cell and a battery module including an anode, a cathode, and an electrolyte provided between the anode and the cathode.

Description

Solid oxide fuel cell and battery module {SOLID OXIDE FUEL CELL AND BATTERY MODULE}

This application claims the benefit of the filing date of Korean Patent Application No. 10-2017-0114410 filed with the Korean Intellectual Property Office on September 7, 2017, the entire contents of which are incorporated herein.

The present specification relates to a solid oxide fuel cell and a battery module including an anode, a cathode, and an electrolyte provided between the anode and the cathode.

Recently, as the depletion of existing energy resources such as oil and coal is predicted, interest in energy that can replace them is increasing. As one of these alternative energies, fuel cells are particularly attracting attention due to advantages such as high efficiency, no emission of pollutants such as NOx and SOx, and abundant fuel used.

A fuel cell is a power generation system that converts the chemical reaction energy of a fuel and an oxidant into electrical energy, and hydrocarbons such as hydrogen, methanol, and butane are used as fuel, and oxygen is used as an oxidant.

Fuel cells include polymer electrolyte fuel cells (PEMFC), direct methanol fuel cells (DMFC), phosphoric acid fuel cells (PAFC), alkali fuel cells (AFC), molten carbonate fuel cells (MCFC), and solid oxide fuels. And SOFCs.

On the other hand, it is also necessary to study a metal air secondary battery in which a cathode of a metal secondary battery is manufactured as an air electrode by applying the principle of the air electrode of the fuel cell.

Republic of Korea Patent Publication No. 2016-0059419 (released May 26, 2016)

The present specification is to provide a solid oxide fuel cell and a battery module comprising an anode, a cathode and an electrolyte provided between the anode and the cathode.

The present specification is a battery cell including an anode, an anode, and an electrolyte layer provided between the anode and the anode; A first separation membrane located on the opposite side of the surface of the air electrode provided with the electrolyte layer, the air being supplied, and having a flow path pattern having a groove pattern and a protruding pattern; A second separator positioned on the opposite side of the surface of the anode provided with the electrolyte layer, the fuel being supplied, and having a flow path pattern having a groove pattern and a protruding pattern; An anode current collector provided between the cathode and the first separator; And an electrically conductive pattern provided along a groove portion pattern of the first separator on a surface of the cathode current collector that faces the first separator, wherein the electrically conductive pattern is inserted into the groove portion pattern of the first separator. , The porosity of the electrically conductive pattern provides a solid oxide fuel cell that is 20% or more and less than 30%.

In addition, the present specification provides a battery module including the above-described solid oxide fuel cell as a unit cell.

The fuel cell of the present specification has an advantage of low current resistance between the battery cell and the separator.

The fuel cell of the present specification has an advantage of good battery performance.

The fuel cell of the present specification has an advantage that air is easily diffused into the battery cell.

1 is a schematic view showing the principle of electricity generation of a solid oxide fuel cell.
2 is a view schematically showing an embodiment of a battery module including a fuel cell.
3 is a front view of a fuel cell according to the present specification.
Figure 4 shows the flow of air in the front view of the fuel cell according to the present specification.
5 is a side view of a fuel cell according to the present specification.
6 is a cross-sectional view showing that the electrically conductive pattern is inserted into the groove portion pattern of the first separator according to an exemplary embodiment of the present invention.
7 is a measured image of a scanning electron microscope (SEM) on the surface of the electrically conductive pattern of Example 1.
8 is a measured image of a scanning electron microscope (SEM) on the surface of the electrically conductive pattern of Example 2.
9 is a measured image of a scanning electron microscope (SEM) on the surface of the electrically conductive pattern of Comparative Example 1.
10 is a measured image of a scanning electron microscope (SEM) on the surface of the electrically conductive pattern of Comparative Example 2.
11 is a measured image of a scanning electron microscope (SEM) on the surface of the electrically conductive pattern of Comparative Example 3.
12 is a result of measuring ohmic resistance of Examples and Comparative Examples.
13 is a battery performance measurement results of Examples and Comparative Examples.
14 is a result of measuring the area resistivity of Examples and Comparative Examples.
15 is a combined cross-sectional view showing that the electrically conductive patterns prepared in Examples 1 and 2 are inserted into the groove portion pattern of the first separator.
16 shows longitudinal cross-sections of various shapes of an electrically conductive pattern according to the present specification.
17 shows cross-sections of various shapes of an electrically conductive pattern according to the present specification.
FIG. 18 shows a ratio of the concentration of oxygen (O ₂ ) according to the height of the electrically conductive pattern according to the height of the electrically conductive pattern provided in the cathode current collector for each penetration rate according to the present specification.
19 is a cross-sectional view of a groove portion pattern of the first separator according to the present specification.

Hereinafter, the present specification will be described in detail.

The present specification is a battery cell including an anode, an anode, and an electrolyte layer provided between the anode and the anode;

A first separation membrane located on the opposite side of the surface of the air electrode provided with the electrolyte layer, the air being supplied, and having a flow path pattern having a groove pattern and a protruding pattern;

A second separator positioned on the opposite side of the surface of the anode provided with the electrolyte layer, the fuel being supplied, and having a flow path pattern having a groove pattern and a protruding pattern;

An anode current collector provided between the cathode and the first separator; And

On the surface opposite to the first separator of the cathode current collector, and includes an electrically conductive pattern provided along the groove portion pattern of the first separator,

The electrically conductive pattern is inserted into the groove portion pattern of the first separator, and the porosity of the electrically conductive pattern is 20% or more and less than 30%.

According to Figure 3, the present specification is an anode, a fuel cell and a battery cell 100 including an electrolyte layer provided between the cathode and the anode; A first separation membrane 200 located on the opposite side of the surface of the air electrode provided with the electrolyte layer, the air is supplied, and the flow path pattern 250 having the groove pattern 210 and the protruding pattern 230 is provided; A second separator positioned on the opposite side of the surface of the anode provided with the electrolyte layer, the fuel being supplied, and having a flow path pattern having a groove pattern and a protruding pattern; An anode current collector 500 provided between the cathode and the first separator; And an electrically conductive pattern 300 provided along a groove portion pattern of the first separator on a surface of the cathode current collector that faces the first separator, wherein the electrically conductive pattern is a groove portion pattern of the first separator. It provides a solid oxide fuel cell that is inserted into.

In one embodiment of the present specification, the average line width of the groove portion pattern of the first separator may be the same as or narrower than the average line width of the electrically conductive pattern. Here, the width of the groove portion pattern 210 of the first separator 200 and the width of the electrically conductive pattern 300 are as shown in FIG. 6.

In one embodiment of the present specification, on the surface of the cathode current collector that faces the first separator, the electrically conductive pattern provided along the groove portion pattern of the first separator may include a plurality of repetitive shapes. .

In one embodiment of the present specification, the average line width of the electrically conductive pattern may be 1 mm to 2 mm. Preferably, the average line width may be 1.2 mm to 1.8 mm. More preferably, the average line width may be 1.5 mm.

As the average line width of the electrically conductive pattern satisfies the above range, diffusion of gas, current collecting performance, and the like can be appropriately maintained.

In one embodiment of the present specification, the “line width” may mean “width”.

In one embodiment of the present specification, the “line width” or “width” means a longitudinal cross-section of one shape included in the electrically conductive pattern, in a direction parallel to a direction in which the shapes included in the electrically conductive pattern are listed. It means the longest line segment among the line segments connecting both ends of the shape.

The “longitudinal cross-section” refers to a cross-section of a shape included in the electrically conductive pattern in a direction parallel to a direction in which the electrically conductive pattern is inserted into the groove portion pattern of the first separator, specifically included in the electrically conductive pattern It means the cross-section of the line segment with the maximum width of the shape.

The porosity of the electrically conductive pattern may be 20% or more and less than 30%. Specifically, the porosity of the electrically conductive pattern may be 20% or more and 26% or less. More specifically, the porosity of the electrically conductive pattern may be 22% or more and 26% or less.

When the porosity of the electrically conductive pattern satisfies the above range, battery performance can be improved and air is easily diffused into the battery cell.

In one embodiment of the present specification, the average height of the electrically conductive pattern may be more than half of the average depth of the groove portion pattern of the first separator. Here, the depth of the groove portion pattern 210 of the first separator 200 and the height of the electrically conductive pattern 300 are as shown in FIG. 6.

The “half or more” means a length of 50% or more and less than 100%, specifically 60% or more and 90% or less, and more specifically 60% or more and 80% or less, based on the total depth of the groove portion pattern of the first separator. Can mean

The “total depth” of the groove portion pattern of the first separation membrane means a length in a direction perpendicular to the width of a cross section of the groove portion pattern of the first separation membrane. The cross-section, width, and depth of the groove portion pattern of the first separator are as shown in FIG. 19.

When the average height of the electrically conductive pattern satisfies the above range, the difference in oxygen concentration in the height direction between the electrolyte layer and the flow path pattern may be reduced. Specifically, by satisfying the above range, the differential pressure in the gas traveling direction of the cathode current collector can be increased. By increasing the differential pressure, the flow rate and flow rate of air can be increased. As the flow rate and flow rate of air increase, the oxygen concentration difference in the height direction between the electrolyte layer and the flow path pattern decreases, and the oxygen concentration in the reaction surface can be maintained high.

In one embodiment of the present specification, the average height of the electrically conductive pattern may be 0.1 mm to 1 mm. Preferably, the average height may be 0.7 mm to 0.9 mm. It may be more preferably 0.1 mm to 0.5 mm.

As the average height of the electrically conductive pattern satisfies the above range, diffusion of gas, current collecting performance, and the like can be appropriately maintained.

In an exemplary embodiment of the present specification, the “height” is an amount of the shape in a direction perpendicular to a direction in which a shape included in the electrically conductive pattern is in a longitudinal section of one shape included in the electrically conductive pattern. It means the longest line segment that connects the end point.

The “transverse cross-section” refers to a cross-section of a shape included in the electrically conductive pattern in a direction perpendicular to the direction in which the electrically conductive pattern is inserted into the groove portion pattern of the first separator, specifically, the height of the electrically conductive pattern It means the cross-section cut by the 0mm point.

The “average” refers to a line width, height, length, or depth of the groove portion pattern included in the electrically conductive pattern of the present specification, and a line width, height, length, or a plurality of shapes included in the electrically conductive pattern. It means that the average value is calculated by measuring the depth of the groove pattern.

In one embodiment of the present specification, the shape included in the electrically conductive pattern is not particularly limited, and may be applied without limitation as long as it can have the electrical conductivity described below.

Specifically, the shape included in the electrically conductive pattern may have an average width of 1 mm to 2 mm and an average height of 0.5 mm to 1 mm based on the longitudinal section.

When the average width and average height of the shapes included in the electrically conductive pattern satisfy the above range, battery performance may be improved and air may easily diffuse into the battery cell.

16 illustrates an example of a longitudinal section of a shape included in the electrically conductive pattern as (a) to (g), and shows an average height and an average line width of the electrically conductive pattern in each shape. The shape included in the electrically conductive pattern is not limited to (a) to (g), and may be employed without limitation as long as it can be applied as the electrically conductive pattern of the present specification.

In one embodiment of the present specification, the shape included in the electrically conductive pattern may include a shape surrounded by a curved line, a straight line, or a combination thereof based on the longitudinal section.

The shape included in the electrically conductive pattern is a square based on a longitudinal section, a square with one rounded corner, a square with two or more rounded corners, a rectangle including one transition curve, a grooved rectangle, a trapezoid, a rhombus , A parallelogram, a quadrilateral, or a polygon, but is not limited thereto. The polygon may be a pentagon or hexagon. The groove may be a semicircular, triangular, or trapezoidal shape based on the longitudinal section, but is not limited thereto.

17 shows an example of a cross section of a shape included in the electrically conductive pattern as (h) to (k). The shape included in the electrically conductive pattern is not limited to (h) to (k), and may be employed without limitation as long as it can be applied as the electrically conductive pattern of the present specification.

In one embodiment of the present specification, the shape included in the electrically conductive pattern may include a shape surrounded by a curved line, a straight line, or a combination thereof based on a cross section.

The shape included in the electrically conductive pattern is a square based on a cross-section, a square with one rounded corner, a square with two or more rounded corners, a square including one transition curve, a grooved square, a trapezoid, a rhombus , A parallelogram, a quadrilateral, or a polygon, but is not limited thereto. The polygon may be a pentagon or hexagon. The groove may be a semicircular, triangular or trapezoidal shape based on the cross section, but is not limited thereto.

In an exemplary embodiment of the present specification, a penetration rate that is such that the electrically conductive pattern is inserted into the groove portion pattern of the first separator is 60% or more.

The penetration rate may be 60% or more and less than 100%, specifically, 60% or more and 90% or less, and more specifically 60% or more and 80% or less.

When the penetration rate satisfies the above range, the difference in oxygen concentration in the height direction between the electrolyte layer and the flow path pattern may be reduced. Specifically, by satisfying the above range, the differential pressure in the gas traveling direction of the cathode current collector can be increased. By increasing the differential pressure, the flow rate and flow rate of air can be increased. As the flow rate and flow rate of air increase, the oxygen concentration difference in the height direction between the electrolyte layer and the flow path pattern decreases, and the oxygen concentration in the reaction surface can be maintained high.

The penetration rate can be calculated by measuring the line width of the electrically conductive pattern and the height of the electrically conductive pattern with a vernier caliper, and measuring the line width of the groove pattern and the depth of the groove pattern.

The penetration rate may mean the degree to which the electrically conductive pattern is inserted into the groove portion pattern. That is, the higher the penetration rate, the greater the degree to which the electrically conductive pattern is inserted into the groove pattern.

The measurement of the oxygen concentration in the height direction between the flow path patterns is based on a current density of 500 mA / cm ² at 600 ° C., and flows about 250 sccm of air per fuel cell cell to the air electrode based on the current density and flows about 50 sccm of hydrogen to the fuel electrode from the electrolyte layer. The concentration of oxygen (O ₂ ) according to the height between the flow path patterns can be measured. Specifically, a single cell of 3 X 3 cm ² can be manufactured and measured with the 1 kW stack of the fuel cell, the current is 4.96 A, the effective area is 9.9225 cm ² , and the fuel utilization rate ( Utilization Factor (UF) may be 70%.

Measurement of the oxygen concentration in the height direction between the flow path patterns can be measured under the following conditions using a Viscous model (Laminar flow).

Density: incompressible ideal gas,

Specific heat: mixing-law,

Thermal conductivity: mass weighted mixing law,

Viscosity: mass weighted mixing law,

Mass diffusivity: kinetic-theory (fluent built-in model),

Working gas: anode (H ₂ , H ₂ O), cathode (N ₂ , O ₂ )

In one embodiment of the present specification, when the porosity of the electrically conductive pattern is 20% or more and less than 30%, and preferably 25%, the penetration rate may be 60% or more and less than 100%.

It is preferable that the electrical conductivity of the electrically conductive pattern has a higher electrical conductivity than the contacting electrode, and specifically, the electrical conductivity of the electrically conductive pattern may be 400S / cm or more. The higher the electrical conductivity of the electrically conductive pattern, the better. The upper limit of the electrical conductivity of the electrically conductive pattern is not limited.

The material of the electrically conductive pattern is not particularly limited as long as it has electrical conductivity, but includes, for example, at least one of platinum (Pt), palladium (Pd), rhodium (Rh), silver (Ag), and gold (Au). can do.

The cathode current collector may be at least one form selected from the group consisting of a foam shape, a mesh shape, a felt shape, and a woven fabric shape, and the material of the cathode current collector is not particularly limited, eg For example, at least one of platinum (Pt), palladium (Pd), rhodium (Rh), silver (Ag), and gold (Au) may be included.

The battery cell may include an air electrode, a fuel electrode, and an electrolyte layer provided between the air electrode and the fuel electrode.

The electrolyte layer may include an oxygen ion-conducting inorganic material, and is not particularly limited if it has oxygen ion conductivity. Specifically, the oxygen ion conductive inorganic material of the electrolyte layer may include a complex metal oxide containing at least one selected from the group consisting of zirconium oxide, cerium oxide, lanthanum oxide, titanium oxide, and bismuth oxide materials. Can be. More specifically, the oxygen ion conductive inorganic material in the electrolyte layer is yttria stabilized zirconium oxide (YSZ: (Y ₂ O ₃ ) _x (ZrO ₂ ) _1-x , x = 0.05 to 0.15), Scandia Stabilized zirconium oxide (ScSZ: (Sc ₂ O ₃ ) x (ZrO ₂ ) _1-x , x = 0.05 ~ 0.15), samarium dope ceria (SDC: (Sm ₂ O ₃ ) x (CeO ₂ ) 1- x, x = 0.02 to 0.4) and gadolinium dope ceria (GDC: (Gd ₂ O ₃ ) x (CeO ₂ ) 1-x, x = 0.02 to 0.4).

The cathode may include an oxygen ion conductive inorganic material. The inorganic particles are not particularly limited as long as they have oxygen ion conductivity, but those generally used in the art may be employed.

For example, the inorganic material of the cathode is yttria stabilized zirconium oxide (YSZ: (Y ₂ O ₃ ) _x (ZrO ₂ ) _1-x , x = 0.05 to 0.15), scandia stabilized zirconium oxide ( ScSZ: (Sc ₂ O ₃ ) x (ZrO ₂ ) _1-x , x = 0.05 ~ 0.15), Samarium dope ceria (SDC: (Sm ₂ O ₃ ) x (CeO ₂ ) 1-x, x = 0.02 to 0.4), gadolinium dope ceria (GDC: (Gd ₂ O ₃ ) x (CeO ₂ ) 1-x, x = 0.02 to 0.4), Lanthanum strontium manganese oxide (LSM), Lanthanum Lanthanum strontium cobalt ferrite (LSCF), Lanthanum strontium nickel ferrite (LSNF), Lanthanum calcium nickel ferrite (LCNF), Lanthanum strontium cobalt oxide: Lanthanum strontium cobalt oxide: Gadolinium strontium cobalt oxide (GSC), Lanthanum strontium ferrite (LSF), Samarium str Lithium cobalt oxide (Samarium strontium cobalt oxide: SSC) and barium strontium cobalt ferrite (Barium Strontium cobalt ferrite: BSCF), and lanthanum strontium gallium magnesium oxide (Lanthanum strontium gallium magnesium oxide: LSGM) may include at least one of.

The anode may include an oxygen ion conductive inorganic material. The inorganic material of the anode is not particularly limited as long as it has oxygen ion conductivity, but one generally used in the art may be employed.

For example, as the inorganic material of the anode, a cermet in which nickel oxide is mixed with the same inorganic material as the oxygen ion conductive inorganic material included in the above-described electrolyte may be used.

The shape of the battery cell is not limited, and may be, for example, coin, flat, cylindrical, horn, button, sheet or stacked.

The battery cell may be specifically used as a power source for electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, or power storage devices.

The present specification provides a battery module including the battery cell as a unit battery.

2 schematically illustrates an embodiment of a battery module including a fuel cell, and the fuel cell includes a battery module 60, an oxidizing agent supply unit 70, and a fuel supply unit 80.

The battery module 60 includes one or two or more of the fuel cells described above as a unit cell, and when two or more unit cells are included, includes a separator interposed therebetween. The separator prevents the unit cells from being electrically connected and transfers fuel and oxidant supplied from the outside to the unit cell.

The oxidizing agent supply unit 70 serves to supply the oxidizing agent to the battery module 60. As the oxidizing agent, oxygen is typically used, and oxygen or air may be injected into the oxidizing agent supply unit 70 to be used.

The fuel supply unit 80 serves to supply fuel to the battery module 60, a fuel tank 81 for storing fuel, and a pump 82 for supplying fuel stored in the fuel tank 81 to the battery module 60 ). As the fuel, gas or liquid hydrogen or hydrocarbon fuel may be used. Examples of hydrocarbon fuels include methanol, ethanol, propanol, butanol or natural gas.

Hereinafter, the present specification will be described in more detail through examples. However, the following examples are only intended to illustrate the present specification and are not intended to limit the present specification.

[Example]

[Example 1]

The solid oxide fuel cell used for the measurement was manufactured with an anode support layer (ASL), an anode functional layer (AFL), an electrolyte layer (EL), and an anode (CL, cathode layer).

As ASL slurry, GDC, NiO, and Carbon Black are used as inorganic materials. The ratio of GDC and NiO is 5: 5 vol%, and carbon black is composed of 10 wt% based on the total weight of the slurry.

In addition, the ASL slurry was added with a dispersant, a plasticizer, and a binder resin with a solvent, based on the total weight of the slurry, 20 wt% of a solvent, 9 wt% of a dispersant, 1 wt% of a plasticizer, and 10 wt% of a binder. ASL Green Sheet having a thickness of 700 μm was obtained from the ASL slurry by tape casting and lamination.

The AFL slurry was the same as the ASL slurry and the organic material, but the composition ratio of GDC and NiO was 6: 4 vol% and carbon black was not included, and 30 μm thick AFL green sheet thinner than ASL was cast using this.

The EL slurry is the same as the ASL slurry and the organic material except the inorganic material, but constitutes an inorganic material only by GDC without NiO and carbon black, and an EL green sheet having a thickness of 30 µm was cast using this.

ASL green sheets, AFL green sheets, and EL green sheets were sequentially laminated and then sintered at 1450 ° C. to produce a half cell. At this time, the thicknesses of ASL, AFL, and EL after sintering were 500 μm, 20 μm, and 20 μm, respectively.

Based on the total weight of the total composition, 70 wt% of inorganics (LSCF: GDC = 5: 5 vol%), and a cathode composition containing 30 wt% of ethylcellulose-butylcarbitol solution as a binder composition was used in a 3 roll mill. By doing so, a cathode composition was prepared in a paste form.

On the electrolyte layer of the half-cell prepared above, the cathode composition was coated by a screen printing method and dried, followed by heat treatment at 1050 ° C. to form an anode.

Nickel mesh was used as the anode current collector to be attached to the manufactured fuel cell.

While forming a silver mesh pattern, which is an anode current collector, on the cathode side of the manufactured fuel cell, as shown in FIG. 15, a width of 1.5 mm and a height of 0.8 mm are symmetrical with the groove pattern of the separator contacting the anode side on the cathode current collector as shown in FIG. The electrically conductive pattern of was also formed.

At this time, the porosity of the cathode current collector and the electrically conductive pattern provided therein was 22%.

7 shows a measured image of a scanning electron microscope (SEM) on the surface of the prepared electrically conductive pattern.

[Example 2]

It was prepared in the same manner as in Example 1, except that the porosity of the cathode current collector and the electrically conductive pattern provided therein was 26%. The measured image of the scanning electron microscope (SEM) on the surface of the prepared electrically conductive pattern is shown in FIG. 8.

[Example 3]

It was prepared in the same manner as in Example 1, except that the porosity of the cathode current collector and the electrically conductive pattern provided therein was 25%.

[Comparative Example 1]

It was prepared in the same manner as in Example 1, except that the porosity of the cathode current collector and the electrically conductive pattern provided therein was 11%. 9 shows a measured image of a scanning electron microscope (SEM) on the surface of the prepared electrically conductive pattern.

[Comparative Example 2]

It was prepared in the same manner as in Example 1, except that the porosity of the cathode current collector and the electrically conductive pattern provided therein was 33%. The measured image of a scanning electron microscope (SEM) on the surface of the prepared electrically conductive pattern is shown in FIG. 10.

[Comparative Example 3]

It was prepared in the same manner as in Example 1, except that the porosity of the cathode current collector and the electrically conductive pattern provided therein was 66%. The measured image of the scanning electron microscope (SEM) on the surface of the prepared electrically conductive pattern is shown in FIG. 11.

[Experimental Example 1]

Resistance measurement was performed by connecting a platinum wire to each electrode of the fuel cell and bonding it to a resistance measurement device located outside the electric furnace equipment, and then measuring the resistance using a 4 probe 2 wire method. At this time, solartron 1287 and 1260 were used as the measurement equipment.

As a result of the measurement, ohmic resistance (Ω) and area specific resistance (Ω * cm ^-2 ) are shown in FIGS. 12 and 14, respectively.

Through this, through the ohmic resistance graph of FIG. 12, it can be seen that the ohmic resistance increases as porosity increases, and through the area specific resistance graph of FIG. 14, the porosity of the electrically conductive pattern is 20% or more and less than 30%. And it can be seen that the interface resistance is lower than the bivalent Comparative Examples 1 to 3.

[Experimental Example 2]

Battery performance of Examples and Comparative Examples was measured at a current of 600 ° C through a current sweep with a potentiostat by flowing 2000 cc of air per fuel cell cell to the cathode and 500 cc of hydrogen to the anode. The results are shown in FIG. 13.

Through this, it can be confirmed that Examples 1 and 2 in which the porosity of the electrically conductive pattern was 20% or more and less than 30% showed better performance than Comparative Examples 1 to 3.

[Experimental Example 3]

The fuel cell prepared in Example 3 flows about 250 sccm of air per fuel cell cell to the air electrode based on the current density of 500 mA / cm ² at 600 ° C. and flows about 50 sccm of hydrogen to the fuel electrode to flow between the flow path patterns from the electrolyte layer. The concentration of oxygen (O ₂ ) according to the height was confirmed and shown in FIG. 18 below.

Specifically, the fuel cell was a single cell of 3 X 3 cm ² in a 1kW stack, and the current was 4.96 A, and the effective area was 9.9225 cm ² , and the utilization factor (UF) ) Was 70%.

0 to 100% of FIG. 18 represents the penetration rate, the horizontal axis represents the height of the electrically conductive pattern provided in the cathode current collector, and the vertical axis represents the oxygen (O ₂ ) concentration ratio according to the height of the electrically conductive pattern.

The oxygen (O ₂ ) concentration ratio was measured under the following conditions using a Viscous model (Laminar flow).

Density: incompressible ideal gas,

Specific heat: mixing-law,

Thermal conductivity: mass weighted mixing law,

Viscosity: mass weighted mixing law,

Mass diffusivity: kinetic-theory (fluent built-in model),

Working gas: anode (H ₂ , H ₂ O), cathode (N ₂ , O ₂ )

The penetration rate was calculated by measuring the line width of the electrically conductive pattern and the height of the electrically conductive pattern with a vernier caliper, and measuring the line width of the groove pattern and the depth of the groove pattern.

Through this, it was confirmed that the oxygen concentration difference in the direction of height between the electrolyte layer of the fuel cell and the flow path pattern decreases when the penetration rate is 60% or more than when the penetration rate is 0 to 40%, so that the oxygen concentration in the reaction surface can be maintained high. Did.

60: battery module
70: oxidizing agent supply unit
80: fuel supply
81: fuel tank
82: Pump
100: battery cell
200: first separator
210: groove pattern of the first separator
230: protrusion pattern of the first separator
250: flow path pattern of the first separator
300: electrically conductive pattern
500: air cathode current collector

Claims (7)

A battery cell including an anode, an anode, and an electrolyte layer provided between the anode and the anode;
A first separation membrane located on the opposite side of the surface of the air electrode provided with the electrolyte layer, the air being supplied, and having a flow path pattern having a groove pattern and a protruding pattern;
A second separator positioned on the opposite side of the surface of the anode provided with the electrolyte layer, the fuel being supplied, and having a flow path pattern having a groove pattern and a protruding pattern;
An anode current collector provided between the cathode and the first separator; And
On the surface opposite to the first separator of the cathode current collector, and includes an electrically conductive pattern provided along the groove portion pattern of the first separator,
The electrically conductive pattern is inserted into the groove portion pattern of the first separator, and the porosity of the electrically conductive pattern is 22% or more and 26% or less. The solid oxide fuel cell of claim 1, wherein an average line width of the groove portion pattern of the first separator is equal to or narrower than an average line width of the electrically conductive pattern. The method according to claim 1, The average height of the electrically conductive pattern is a solid oxide fuel cell that is at least half the average depth of the groove portion pattern of the first separator. The method according to claim 1, wherein the electrically conductive pattern is a solid oxide fuel cell having a penetration rate of 60% or more such that the groove portion pattern of the first separator is inserted. The solid oxide fuel cell of claim 1, wherein the electrical conductivity of the electrically conductive pattern is 400S / cm or more. The method according to claim 1, The electrically conductive pattern is a solid oxide fuel cell comprising at least one of platinum (Pt), palladium (Pd), rhodium (Rh), silver (Ag) and gold (Au). A battery module comprising the solid oxide fuel cell according to any one of claims 1 to 6 as a unit cell.

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