KR102626015B1 - Manufacturing method for a solid oxide fuel cell stack - Google Patents

Abstract

This specification relates to a method of manufacturing a solid oxide fuel cell stack and a solid oxide fuel cell stack.

Description

Manufacturing method of solid oxide fuel cell stack and solid oxide fuel cell stack {MANUFACTURING METHOD FOR A SOLID OXIDE FUEL CELL STACK}

This specification relates to a method of manufacturing a solid oxide fuel cell stack and a solid oxide fuel cell stack.

Fuel cells require tens to hundreds of unit cells to be connected in series to achieve the target output. In particular, in the case of planar fuel cells, the cells are stacked vertically to reach the desired target output. At this time, even surface pressure distribution between layers is an important factor that directly affects stack performance and durability.

Accordingly, various methods of improving structural devices and pressurizing methods are being attempted for this purpose. This invention relates to a method of using and conditioning sealants used to form interlayer adhesion and sealing.

Typically, a glass sealant is used to form a seal. The glass sealant is applied to the adhesive surface of each component at room temperature or a layer in the form of a gasket is inserted and laminated, followed by appropriate conditioning (heating, pressurization). use. During conditioning, the glass begins to melt (softening) from the glass transition temperature (Tg). At this time, appropriate pressure is applied to the stack to fill the gap between layers and at the same time form an appropriate thickness to form an internal seal.

However, this method does not pose a problem when manufacturing a stack with a low number of layers (e.g., a stack containing 10 or less cells), but when manufacturing a high-layer stack, the temperature imbalance between layers applied during conditioning causes a problem. It is difficult for the sealant to collapse at the same time, making it difficult to produce a vertically straight stack.

Figure 1 schematically shows the principle of electricity generation in a solid oxide fuel cell. The solid oxide fuel cell consists of an electrolyte, an anode, and a cathode formed on both sides of the electrolyte. Referring to Figure 1, which shows the principle of electricity generation in a solid oxide fuel cell, oxygen ions are generated as air is electrochemically reduced at the air electrode, and the generated oxygen ions are transferred to the fuel electrode through the electrolyte. In the anode, fuel such as hydrogen, methanol, butane, etc. is injected, and the fuel combines with oxygen ions and is electrochemically oxidized, giving up electrons and generating water. This reaction causes the movement of electrons to the external circuit.

Korean Patent Publication No. 10-2005-0071887 (published on July 8, 2005)

This specification relates to a method of manufacturing a solid oxide fuel cell stack and a solid oxide fuel cell stack.

This specification includes the steps of providing unit cells each including a fuel electrode, an electrolyte, and an air electrode on a self-frame; providing a separator plate between the unit cells; providing a sealing material in the self-frame by providing a sealing material between the self-frame and the separation plate and between the self-frame and the unit cell; and the step of heating and pressurizing, wherein the step of providing a sealing material to the self-frame is to repeat n times a unit cycle consisting of repeatedly using a sealing material having the same glass transition temperature in m self-frames, and any one of the above The glass transition temperature (Tg) of the sealing material used in the unit cycle and the adjacent unit cycle is different from each other, m is an integer from 1 to 30 that is the same or different for each unit cycle, and n is an integer from 2 to 20. A method for manufacturing a solid oxide fuel cell stack is provided.

In addition, the present specification provides a solid oxide fuel cell stack that is manufactured by the above-described manufacturing method and satisfies Equation 1 below.

[Equation 1]

In equation 1 above,

Hmax is the highest height of the solid oxide fuel cell stack, Hmin is the lowest height of the solid oxide fuel cell stack, and L is the largest length of the self-frame either horizontally or vertically.

According to the method for manufacturing a solid oxide fuel cell stack of the present specification, the sealing material applied between cells sequentially melts according to the number of cells stacked, thereby preventing the stack from tilting, thereby manufacturing a solid oxide fuel cell stack with an upright structure. You can.

1 is a schematic diagram showing the electricity generation principle of a solid oxide fuel cell (SOFC).
Figure 2 is a diagram showing the manufacturing method of the solid oxide fuel cell stack of Example 1.
Figure 3 shows a solid oxide fuel cell stack according to Example 1.
Figure 4 is a diagram showing the manufacturing method of the solid oxide fuel cell stack of Comparative Example 1.
Figures 5 to 8 show the solid oxide fuel cell stack of Comparative Example 1.
Figure 9 briefly shows the structure of Selfframe.

Hereinafter, this specification will be described in detail.

This specification includes the steps of providing unit cells each including a fuel electrode, an electrolyte, and an air electrode on a self-frame;

providing a separator plate between the unit cells;

providing a sealing material in the self-frame by providing a sealing material between the self-frame and the separation plate and between the self-frame and the unit cell; and

Including heating and pressurizing,

The step of providing a sealing material to the self-frame is to repeat n times a unit cycle consisting of repeatedly using a sealing material with the same glass transition temperature in m self-frames,

The glass transition temperature (Tg) of the sealing material used in one of the unit cycles and the adjacent unit cycle is different from each other,

The m is an integer from 1 to 30 that is the same or different for each unit cycle,

Provided is a method of manufacturing a solid oxide fuel cell stack, wherein n is an integer of 2 to 20.

As a result, compared to the case where the glass transition temperatures of the sealing materials applied between unit cells are all the same or the glass transition temperatures of the sealing materials applied between unit cells do not sequentially decrease but increase or decrease, etc., there is no tendency. It has excellent lamination stability. Specifically, the glass transition temperature (Tg) of the sealant applied in each unit application cycle sequentially decreases according to the number of unit application cycles, so when heated and pressed at high temperature and pressure, the sealant located in the upper layer to the sealant located in the lower layer By sequentially softening the cell, it is possible to prevent the cell from tilting.

In this specification, the “cell frame” is a structure that supports unit cells, may be referred to as a window frame, and may be made of either ceramic or metal. This is shown in Figure 9.

In this specification, the “unit cell” refers to the most basic unit of a fuel cell including a fuel electrode, electrolyte, and air electrode. When m unit cells are sequentially stacked, they are stacked so that the fuel electrode included in one unit cell and the air electrode included in another unit cell come into contact with each other.

In this specification, the “sealing material” may be used as a connecting material that connects each component of the fuel cell to each other, prevents the fuel gas supplied to the anode and the air supplied to the cathode from mixing with each other, and prevents gas leakage to the outside. It plays a role in preventing. These sealing materials are very important core components to ensure the thermomechanical stability and long life of the solid oxide fuel cell stack. Meanwhile, the sealant may be expressed as a “sealing material composition.”

In this specification, the “separator plate” is configured to prevent mixing of fuel gas and air while electrically connecting the unit cells. The separator basically uses a ferritic stainless steel plate based on Fe-Cr, provides a passage for gas to move through the air electrode and fuel electrode, and requires a function to electrically connect cells. .

In this specification, the “unit cycle” means one cycle consisting of sequentially stacking m unit cells by applying a sealant between unit cells. Additionally, the glass transition temperature (Tg) of the sealant applied within one unit application cycle may be the same.

In this specification, “a unit cycle adjacent to any one unit cycle” may mean a unit cycle adjacent in order. For example, the first unit cycle and the second unit cycle are adjacent, and the first unit cycle and the third unit cycle are unit cycles that are not adjacent in order.

In this specification, the “glass transition temperature (Tg) of the sealant” refers to the transition temperature and is a physical property related to the thermal, chemical, mechanical, or electrical properties of the sealant. The glass transition temperature can be measured by raising the temperature from room temperature to 800°C at 10°C per minute using a DSC (differential scanning calorimeter, DSC-60A, Shimadzu, Japan). Alternatively, after manufacturing the sealing material in the form of a pellet, the degree of thermal expansion according to temperature changes can be measured and calculated using a dilatometer.

In one embodiment of the present specification, the composition of the sealing material is not particularly limited as long as it satisfies the glass transition temperature (Tg) condition of the sealing material.

In one embodiment of the present specification, the sealing material may include glass powder. Here, the glass powder refers to a powder of a material in a glass state. At this time, the glassy state refers to a state in which the molten liquid cools and solidifies without crystallizing, and the inorganic material in the glassy state is called glass. The glass powder may be a powder of glass commonly used in the art. For example, the glass powder may be a powder of oxide glass.

In an exemplary embodiment of the present specification, the glass powder is B ₂ O ₃ , Bi ₂ O ₃ , Li ₂ O, Na ₂ O, K ₂ O, Rb ₂ O, Cs ₂ O, Sb ₂ O ₃ , SnO, It includes at least one first compound selected from the group consisting of La ₂ O ₃ and PbO.

In one embodiment of the present specification, the glass powder includes at least one second compound selected from the group consisting of Al ₂ O ₃ , BaO, CaO, MgO, ZnO, SrO, TiO ₂ , and Y ₂ O ₃ do.

In one embodiment of the present specification, the glass powder includes silicon dioxide (SiO ₂ ).

In one embodiment of the present specification, the contents of the first compound, the second compound, and SiO ₂ are the same or different, and are 0.1 wt% to 60 wt%, or 16 wt% to 20 wt%, respectively, based on the total weight of the glass powder. , 45 wt% to 55 wt%, 10 wt% to 15 wt%, or 0.1 wt% to 3 wt%.

In the present specification, the sealant composition may further include at least one of a binder, a plasticizer, a dispersant, and a solvent. The binder, plasticizer, dispersant, and solvent are not particularly limited, and common materials known in the art can be used.

In one embodiment of the present specification, the binder is poly(butyl methacrylate) (PBMA) and poly(2-ethylhexyl methacrylate) (PEHMA) copolymer (PBMA-PEHMA), ethyl cellulose (EC), polyvinyl isobutyral (PViB, Poly vinylisobutyral) and poly (2-ethylhexyl acrylate) (PEHA, Poly(2-ethylhexylacrylate)). It may include at least one, preferably SOKEN LRRS001.

In one embodiment of the present specification, based on the total weight of the sealant composition, the content of the binder may be 1% by weight or more and 20% by weight or less.

In one embodiment of the present specification, the plasticizer is commercial products such as dibutyl phthalate (DBP, Di-butyl-phthalate), di-2-ethylhexyl phthalate (DOP, Di-2-ethylhexyl phthalate), and di-isononyl phthalate. It may be at least one of (DINP, Di-isononyl phthalate), di-isodecyl phthalate (DIDP, Di-isodecylphthalate), and butyl benzyl phthalate (BBP, Butyl benzyl phthalate).

In one embodiment of the present specification, based on the total weight of the sealant composition, the content of the plasticizer may be 0.1% by weight or more and 5% by weight or less.

In one embodiment of the present specification, the dispersant may be at least one of BYK-110, BYK-111, and BYK-112.

In one embodiment of the present specification, based on the total weight of the sealant composition, the content of the dispersant may be 5% by weight or more and 15% by weight or less.

In one embodiment of the present specification, the solvent is not particularly limited as long as it is a material that disperses the glass powder and is easy to remove from the film or green sheet, and common materials known in the art can be used. For example, the solvent is at least one selected from water, isopropanol, toluene, ethanol, n-propanol, n-butyl acetate, ethylene glycol, butyl carbitol (BC), and butyl carbitol acetate (BCA). It can be included.

In one embodiment of the present specification, based on the total weight of the sealant composition, the content of the solvent may be 10% by weight or more and 40% by weight or less.

In the present specification, the glass transition temperature (Tg) of the sealant applied in each unit application cycle sequentially decreases according to the number of unit application cycles. Sequential decrease means that the glass transition temperature of the sealant applied in the next application cycle is smaller than the glass transition temperature of the sealant applied in one application cycle.

In this specification, m refers to the number of unit cells stacked in one unit application cycle.

In one embodiment of the present specification, m may be an integer of 2 to 30, an integer of 2 to 20, or an integer of 5 to 15. When the above numerical range is satisfied, the number of unit cells stacked in one unit application cycle is maintained within a certain range, so it is possible to effectively prevent the stack from tilting even if the height of the stack increases.

In this specification, n refers to the number of unit application cycles included in the entire stack.

In one embodiment of the present specification, n may be an integer of 2 to 20, an integer of 2 to 15, or an integer of 3 to 10. When the above numerical range is satisfied, the number of application cycles can be adjusted to a certain range to effectively prevent the stack from tilting even if the stack height increases.

In this specification, the product of m and n means the total number of unit cells included in the stack.

In an exemplary embodiment of the present specification, the product of m and n may be 10 to 300, 10 to 100, 20 to 80, or 20 to 50. If the above numerical range is satisfied, the number of unit cells included in the stack can be adjusted to a certain range.

In the present specification, the difference between the glass transition temperature (Tg) of the sealing material used in any one of the unit cycles and the adjacent unit cycle is 100 ℃ or more and 300 ℃ or less, preferably 120 ℃ or more and 250 ℃ or less, more preferably It is 130℃ or higher and 200℃ or lower, and n is an integer of 2 or higher. When the above numerical range is satisfied, the glass transition temperature distribution of the sealant applied for each cycle can be effectively achieved.

In this specification, the heating and pressurizing steps are steps for melting (softening) the applied sealant, applying appropriate pressure to the stack to fill gaps between unit cells, and forming a seal inside the stack.

In one embodiment of the present specification, the heating and pressurizing step is performed at a final temperature of 400°C to 750°C and a final pressure of 100 kgf/(15*15cm ² ) to 350 kgf/(15*15cm ² ), The final temperature and final pressure may be maintained for 1 to 10 hours. When the above numerical range is satisfied, the fuel cell stack can be maintained in an upright state without collapsing.

In this specification, the pressure condition may be a condition for applying a corresponding force to the corresponding area. For example, 100 kgf/(15*15cm ² ) may mean applying a force of 100 kgf to an area of 15*15cm ² .

In one embodiment of the present specification, the heating and pressurizing step may be heating from the initial temperature at a temperature increase rate of 0.25 ℃/min to 1 ℃/min. The initial temperature may be an initial temperature before performing the heating and pressurizing steps, and may be, for example, 25°C.

In one embodiment of the present specification, the heating and pressurizing step is performed at a pressing rate of 0.5 kgf/[(15*15cm ² )*min] to 3 kgf/[(15*15cm ² )*min] from the initial pressure. It may be pressurizing.

In one embodiment of the present specification, the heating and pressurizing steps may be performed two or more times, and specifically, may be performed 2 to 10 times. The nth heating and pressurizing step can be expressed as the nth heating and pressurizing step.

Additionally, the temperature and pressure conditions of each stage can be adjusted differently.

In one embodiment of the present specification, the heating and pressurizing step may increase or decrease one or more of the final temperature and final pressure depending on the number of times it is performed. For example, the heating and pressurizing

In an exemplary embodiment of the present specification, the heating and pressurizing step may increase one or more of the final temperature and final pressure depending on the number of times it is performed.

In one embodiment of the present specification, the final temperature and final pressure may increase depending on the number of times the heating and pressurizing step is performed. Specifically, the heating and pressurizing step is performed twice, a first heating and pressurizing step and a second heating and pressurizing step, and the final temperature and final pressure of the second heating and pressurizing step are the final temperature and final pressure of the first heating and pressurizing step. It may be higher than the temperature and final pressure.

In one embodiment of the present specification, the heating and pressurizing step involves performing one cycle of heating and pressurizing two or more times, and as the number of cycles increases, the performance temperature ranges from 25°C to 100°C and 30°C to 90°C. Alternatively, it may increase by 35°C to 80°C.

In one embodiment of the present specification, the heating and pressurizing steps are performed two or more times, and depending on the number of times performed, the final pressure is 10 to 150 kgf/(15*15cm ² ), preferably 20 to 120 kgf/(15* 15cm ² ), more preferably 30 to 100kgf/(15*15cm ² ).

When the above numerical range is satisfied, the stack is prevented from collapsing at once by melting the sealant applied to each layer sequentially from the sealant located in the upper layer to the sealant located in the lower layer, rather than melting simultaneously. In addition, adjusting the operating temperature and operating pressure within the above numerical range takes into account the glass transition temperature of the applied sealant.

In one embodiment of the present specification, the method of providing the sealant includes a method of screen printing a sealant composition; A method of directly applying the sealant composition through a syringe; and a method of providing a sealant made of a gasket.

This specification provides a solid oxide fuel cell stack manufactured by the above-described manufacturing method and satisfying Equation 1 below.

[Equation 1]

In equation 1 above,

Hmax is the highest height of the solid oxide fuel cell stack,

Hmin is the lowest height of the solid oxide fuel cell stack,

L is the largest horizontal or vertical length of the self-frame.

In this specification, Hmax refers to the distance from the highest point of the unit cell located on the top layer of the manufactured solid oxide fuel cell stack to the ground when placed on a flat ground.

In this specification, Hmin refers to the distance from the lowest point of the unit cell located on the top layer of the manufactured solid oxide fuel cell stack to the ground when placed on a flat ground.

In this specification, the may mean the tilt angle of the fuel cell stack. Hmax-Hmin in the molecule refers to the height difference of the tilted fuel cell stack, and L refers to the largest length of the self-frame horizontally or vertically. means the tangent value of the tilt angle (θ) of the fuel cell stack.

In an exemplary embodiment of the present specification, the [Formula 1] may be expressed as the following [Formula 2] or [Formula 3].

[Equation 2]

[Equation 3]

In one embodiment of the present specification, the electrolyte may include a solid oxide having ion conductivity. Specifically, in one embodiment of the present specification, the electrolyte is a composite metal oxide containing at least one selected from the group consisting of zirconium oxide-based, cerium oxide-based, lanthanum oxide-based, titanium oxide-based, and bismuth oxide-based materials. may include. More specifically, the electrolyte may include yttria-stabilized zirconia (YSZ), scandia-stabilized zirconia (ScSZ), samaria-doped ceria (SDC), and gadolinia-doped ceria (GDC).

In one embodiment of the present specification, the YSZ is yttria-stabilized zirconium oxide, and may be expressed as (Y ₂ O ₃ ) _x (ZrO ₂ ) _1-x , and x may be 0.05 to 0.15. , the ScSZ is Scandinavian stabilized zirconium oxide, and can be expressed as (Sc ₂ O ₃ ) _x (ZrO ₂ ) _1-x , and x can be 0.05 to 0.15. Additionally, in one embodiment of the present specification, the SDC is samarium dope ceria, and may be expressed as (Sm ₂ O ₃ ) _x (CeO ₂ ) _1-x , x may be 0.02 to 0.4, and the GDC is Gadorium dopseria, and can be expressed as (Gd ₂ O ₃ ) _x (CeO ₂ ) _1-x , and x can be 0.02 to 0.4.

In one embodiment of the present specification, the air electrode 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 commonly used in the art can be adopted.

For example, _the inorganic material of _the air electrode includes yttria stabilized zirconia ( _YSZ : (Y ₂ O ₃ ) _ScSZ : (Sc ₂ O ₃ ) _{x (} ZrO ₂ ) _1-x , x = 0.05 to 0.15), samarium doped ceria (SDC: (Sm _{2 O 3} ) 0.02 ~ 0.4), gadolinium dope ceria (GDC: (Gd ₂ O ₃ ) _x (CeO ₂ ) _1-x , x = 0.02 ~ 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 (LSC) , Gadolinium strontium cobalt oxide (GSC), Lanthanum strontium ferrite (LSF), Samarium strontium cobalt oxide (SSC), Barium Strontium cobalt ferrite (BSCF) ) and lanthanum strontium gallium magnesium oxide (LSGM).

The fuel electrode may include an oxygen ion conductive inorganic material. The inorganic material of the fuel electrode is not particularly limited as long as it has oxygen ion conductivity, but any material commonly used in the art can be adopted.

For example, the inorganic material of the fuel electrode may be cermet, which is a mixture of nickel oxide and the same inorganic material as the oxygen ion conductive inorganic material contained in the above-mentioned electrolyte.

Hereinafter, the present invention will be described in more detail through examples. These examples are for illustrating the present invention in more detail, and it is obvious to those skilled in the art that the scope of the present invention is not limited by these examples.

Example 1

Thirty unit cells containing an air electrode, electrolyte, and fuel electrode were prepared. In addition, 30 self-frames, 29 separator plates, and 2 end plates were prepared to support the 30 cells.

The first sealant material is SiO ₂ 16 to 20 wt%, B ₂ O ₃ 16 to 20 wt%, BaO 45 to 55 wt%, CaO 10 to 15 wt%, MgO 0.1 to 3 wt%, Al ₂ O ₃ 0.1 to 3 wt%, and A first glass containing 0.1 to 3 wt% SrO was prepared. At this time, the glass transition temperature of the first glass is 570°C.

A second glass containing 20 to 30 wt% of SiO ₂ , 5 to 15 wt% of B ₂ O ₃ , 5 to 15 wt% of CaO, and 45 to 55 wt% of BaO was prepared as a second sealant material. At this time, the glass transition temperature of the second glass is 720°C.

A first sealant paste and a second sealant paste were prepared by mixing each of the above glasses at 79 wt% in a toluene solvent containing 10 parts by weight of binder (SOKEN LRRS001).

Unit cells were provided on the self-frame, and the separation plate was provided between each unit cell.

A sealing material was provided between the self-frame and the separator plate and between the self-frame and the unit cell.

The first sealant paste was applied as a sealant material to the 1st to 10th self-frames using a syringe, the second sealant paste was applied to the 11th to 20th self-frames using a syringe as a sealant material, and the 21st self-frame was applied as a sealant material using a syringe. The first sealant paste was applied as a sealant material to the 30th to 30th self-frames using a syringe.

The manufactured stack is placed in the center of a heating and pressurizing furnace (conditioning furnace) and heated at a temperature increase rate of 0.25°C/min to 1°C/min from an initial temperature of 25°C using equipment to raise the temperature inside the furnace. 540°C to 550°C was maintained, and pressure was maintained from an initial pressure of 40 to 100kgf/(15*15cm ² ) to a final pressure of 150kgf/(15*15cm ² ) for 1 to 2 hours. At this time, it was confirmed that the 21st to 30th layers of sealant to which the first sealant paste was applied were collapsing.

Thereafter, the final temperature inside the furnace was maintained at 600°C by heating at a temperature increase rate of 0.25°C/min to 1°C/min, and the furnace was pressurized to a final pressure of 200kgf/(15*15cm ² ) and maintained for 1 to 2 hours. . At this time, it was confirmed that the 11th to 20th layers of sealant to which the second sealant had been applied were collapsing.

The manufacturing process is conceptually shown in Figure 2.

The final completed solid oxide fuel cell stack is shown in Figure 3. Referring to FIG. 3, it can be confirmed that the stack was manufactured without tilting by sequentially softening the sealing material of each layer.

Comparative Example 1

Thirty unit cells containing the same air electrode, electrolyte, and fuel electrode as in Example 1 were prepared. In addition, 30 cell frames, 29 interconnects, and 2 end plates were prepared to support the 30 cells.

A stack was manufactured by applying the same first sealant paste to the 1st to 30th self-frames.

The manufactured stack is placed in the center of a heating and pressurizing furnace (conditioning furnace) and heated at a temperature increase rate of 0.25°C/min to 1°C/min from an initial temperature of 25°C using equipment to raise the temperature inside the furnace. 570°C was maintained, and the pressure was increased from an initial pressure of 40 to 100 kgf/(15*15cm ² ) to a final pressure of 250 kgf/(15*15cm ² ) and maintained for 1 to 2 hours. At this time, it was confirmed that the 1st to 30th layers of sealant to which the first sealant paste was applied collapsed simultaneously.

The manufacturing process is conceptually shown in Figure 4.

The final completed solid oxide fuel cell stack is shown in Figures 5 to 8. Referring to FIG. 5, it can be seen that the stack is tilted due to simultaneous softening of the sealant of each layer.

From the results of Example 1 and Comparative Example 1, it was confirmed that the fuel cell stack could be manufactured without tilting according to the manufacturing method of the solid oxide fuel cell stack described above.

Claims (10)

Providing unit cells each including a fuel electrode, an electrolyte, and an air electrode on a self-frame;
providing a separator plate between the unit cells;
providing a sealing material in the self-frame by providing a sealing material between the self-frame and the separation plate and between the self-frame and the unit cell; and
Including heating and pressurizing,
The step of providing a sealing material to the self-frame is to repeat n times a unit cycle consisting of repeatedly using a sealing material with the same glass transition temperature in m self-frames,
The glass transition temperature (Tg) of the sealing material used in one of the unit cycles and the adjacent unit cycle is different from each other,
The m is an integer from 1 to 30 that is the same or different for each unit cycle,
where n is an integer from 2 to 20,
The heating and pressurizing step involves performing one cycle of heating and pressurizing two or more times, and as the number of cycles increases, the operating temperature increases by 25°C to 100°C,
A method of manufacturing a solid oxide fuel cell stack, wherein the difference between the glass transition temperature (Tg) of the sealing material used in any one of the unit cycles and the adjacent unit cycle is 100 ℃ or more and 300 ℃ or less. The method of manufacturing a solid oxide fuel cell stack according to claim 1, wherein m is an integer of 2 to 30. delete The method of manufacturing a solid oxide fuel cell stack according to claim 1, wherein the product of m and n is 10 to 300. delete The method of claim 1, wherein the heating and pressurizing step is performed at a final temperature of 400°C to 750°C and a final pressure of 100 kgf/(15*15cm ² ) to 350 kgf/(15*15cm ² ) for 1 hour to 10 minutes. A method of manufacturing a solid oxide fuel cell stack, wherein the final temperature and final pressure are maintained for a period of time. delete delete The method of claim 1, wherein the method of providing the sealant includes a method of screen printing a sealant composition; A method of directly applying the sealant composition through a syringe; and a method of manufacturing a solid oxide fuel cell stack, which is selected from the group consisting of a method of providing a sealant made of a gasket. A solid oxide fuel cell stack manufactured by the method for manufacturing a solid oxide fuel cell stack according to any one of claims 1, 2, 4, 6, and 9, and satisfying the following equation 1:
[Equation 1]

In equation 1 above,
Hmax is the highest height of the solid oxide fuel cell stack,
Hmin is the lowest height of the solid oxide fuel cell stack,
L is the largest horizontal or vertical length of the self-frame.