KR20220132253A - Manufacturing method of polymer electrolyte fuel cell using adhesive transfer and polymer electrolyte fuel cell manufactured by the same - Google Patents

Abstract

The present invention relates to a manufacturing method of a polymer electrolyte fuel cell by using adhesive transfer and a polymer electrolyte fuel cell manufactured thereby, which comprises: a catalyst layer formation step of applying a catalyst to one side surface of an anode to form a first catalyst layer and applying a catalyst to one side surface of a cathode to form a second catalyst layer; an adhesive layer formation step of transferring an adhesive to a top surface of the first catalyst layer to form a first adhesive layer and transferring an adhesive to a top surface of the second catalyst layer to form a second adhesive layer; and a membrane-electrode assembly formation step of disposing an electrolyte membrane between the first adhesive layer and the second adhesive layer and pressurizing the same with a compressor to form a membrane-electrode assembly, wherein the electrode consisting of the anode and the cathode and the electrolyte membrane are pressurized at room temperature, so that the membrane-electrode assembly can be simply and rapidly completed.

Description

A method for manufacturing a polymer electrolyte fuel cell using adhesive transfer and a polymer electrolyte fuel cell manufactured therefrom

The present invention relates to a method for manufacturing a polymer electrolyte fuel cell using pressure-sensitive adhesive transfer and to a polymer electrolyte fuel cell manufactured by the manufacturing method.

Polymer electrolyte fuel cell is an energy conversion device that produces electricity by a combination of oxidation reaction of hydrogen and alcohol molecules at the anode, which is the anode, and the reduction reaction of oxygen molecules at the cathode, which is the cathode.

The unit cell or membrane-electrode assembly (MEA) of a polymer electrolyte fuel cell is composed of a fuel electrode, an air electrode, and a polymer electrolyte membrane. An electrode assembly is manufactured.

The production of the membrane-electrode assembly is largely divided into a Catalyst-Coated Membrane (CCM) method, a Catalyst-Coated Substrate (CCS) method, and a Decal transfer method. 3 is shown.

The Catalyst-Coated Membrane (CCM) method directly coats the catalyst layers of the anode and cathode on both sides of an electrolyte membrane. A material is prepared (S111, S131), and a cathode material and an anode material are sequentially coated on both sides of the electrolyte membrane and compressed to prepare a membrane-electrode assembly. Specifically, the cathode material is coated on one side of the electrolyte membrane (S122) and compressed to form an adhesive, and the anode material is coated on the other side of the electrolyte membrane located opposite to the surface to which the cathode is adhered (S125), and the process of pressing A final membrane-electrode assembly is prepared by adhesively forming the anode in (S127).

In the case of manufacturing a membrane-electrode assembly by the CCM method, when pattern coating is applied with a slot-die coater, etc., it is unnecessary to cut the electrode and it is easy to realize adhesion between the electrode and the electrolyte membrane. In addition, it may be easier to manufacture a high-loading electrode compared to other processes.

However, in the CCM method, it is difficult to distinguish between the electrode and the assembly process, making it difficult to manage the process, and since the unwinding electrolyte membrane is exposed to the air for a long time, it is important to manage the humidity and temperature of the process line. In addition, there is a high possibility of desorption of the coated electrode during the compression process. Therefore, the discontinuous batch type can be applied to manufacturing a membrane-electrode assembly, but it is difficult to apply it as a continuous R/R process for mass production.

In the Catalyst-Coated Substrate (CCS) method, as shown in FIG. 2 , an electrode catalyst, an ionic binder, and a solvent are mixed to prepare each anode material and cathode material as an electrode (S211, S231), and the reactants and products are diffused The catalyst layer of the electrode is coated on the surface of carbon paper, etc. with a support that functions as a current collector, dried and cut to an appropriate size to prepare an electrode, and the electrode and the electrolyte membrane are adhered by lamination (S240). A membrane-electrode assembly is prepared.

In the case of the CCS method, it is easy to manage the process because the electrode and the assembly process can be distinguished. The short unwinding period of the electrolyte membrane makes it easy to manage the humidity and temperature of the line compared to CCM. Since it is easy to implement a continuous R/R process and a membrane-electrode assembly including a support (carbon paper, etc.) is manufactured, the stacking process can be simplified.

However, in the CCS method, it may be difficult to implement adhesion between the electrode and the electrolyte membrane, so excessive temperature, pressure, and time must be set for lamination. In order to manufacture a large-area membrane-electrode assembly, it is necessary to design a huge press facility for temperature and pressure, and it may be necessary to reflect the design, such as off-set of process conditions, and repeatability and reproducibility of applying uniform process conditions. Since it is difficult to secure, there are restrictions on the process speed increase, making it difficult to satisfy production efficiency.

In addition, when using the CCS method, in order to prevent damage to the perfluorosulfonic acids ( _PFSAs ), which are the main materials of the electrolyte membrane and binder (ionomer) due to excessive lamination, hydrogen cations (H ⁺ ) to Na ⁺ , K ⁺ , Tert-butylammonium(TBA) ⁺ , or vice versa, a cationic substitution and reverse substitution process may be required.

In the CCS method, when different sizes of anode and cathode are applied, defects such as electrode breakage may occur at the edges of large electrodes, so it is difficult to design different dimensions of the anode and cathode, and it is difficult to secure the quality of the cut surface in cutting including the support. need. Since the electrode slurry is coated on the surface of the porous support, performance degradation of the support may occur due to the penetration of the slurry into the pores of the support.

In the electrolyte membrane edge-failure at the electrode edge of the completed electrolyte membrane-electrode assembly, mixed potential generation due to the incorporation of hydrogen and oxygen may cause a problem of initial performance degradation such as low voltage generation. In addition, the transport of hydroxyl (HO·) or hydroperoxyl (HO ₂ ·) radicals generated by incomplete reduction at the cathode to the cathode is facilitated, and the degradation of the polymer electrolyte membrane or the anode binder or ionomer is accelerated. can be

The decal transfer method is similar to the CCS method described above, and as shown in FIG. 3 , the catalyst layer of the electrode is coated on the surface of a separate release film instead of the support (S313, S333), dried, and then transferred to the electrolyte membrane surface (Decal transfer) and lamination (Lamination, S340) is a method of manufacturing a membrane-electrode assembly by bonding the electrode and the electrolyte membrane.

The decal transfer method has a process flow and advantages similar to that of CCM, but the use of a release film increases the material cost, and considering the transfer efficiency, it is difficult to secure production capacity because it is difficult to increase the process speed. In addition, like CCM, excessive lamination conditions such as excessive temperature, pressure, and time are required to realize adhesion between the electrode and the electrolyte membrane.

Korean Patent Registration No. 10-0774729

As described above, there are various methods of manufacturing the conventional membrane-electrode assembly, but as described above, various technical problems occur. In consideration of such problems, the present invention provides a polymer electrolyte fuel cell using a pressure-sensitive adhesive transfer that can quickly and simply complete a membrane-electrode assembly by transferring and applying a thin adhesive to the electrode surface or electrolyte membrane and then lightly pressurizing the electrode and electrolyte membrane at room temperature. An object of the present invention is to provide a method for manufacturing and a polymer electrolyte fuel cell manufactured thereby.

In the method for manufacturing a polymer electrolyte fuel cell of the present invention for achieving the above object, a catalyst layer is formed by coating a catalyst on one side of an anode to form a first catalyst layer, and coating a catalyst on one side of an anode to form a second catalyst layer Step, forming a first pressure-sensitive adhesive layer by transferring a pressure-sensitive adhesive to the upper surface of the first catalyst layer, forming a pressure-sensitive adhesive layer by transferring the pressure-sensitive adhesive to the upper surface of the second catalyst layer to form a second pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer and the It may include the step of placing the electrolyte membrane between the second pressure-sensitive adhesive layer and pressing with a press to form a membrane-electrode assembly.

In the method for manufacturing a polymer electrolyte fuel cell of the present invention, the catalyst layer forming step is performed by using any one method selected from a Catalyst-Coated Membrane (CCM) method, a Catalyst-Coated Substrate (CCS) method, and a Decal Transfer method. to form a catalyst layer.

When the catalyst layer is formed by using the Catalyst-Coated Membrane (CCM) method in the step of forming the catalyst layer, the catalyst layer may be formed by directly applying the catalyst to one side of the fuel electrode and the cathode.

When the catalyst layer is formed by using the Catalyst-Coated Substrate (CCS) method in the catalyst layer forming step, the catalyst layer is applied to the surface of the support and the support on which the catalyst layer is formed is attached to one side of the fuel electrode and the cathode to form a catalyst layer. can do.

In the case of forming the catalyst layer using a decal transfer method, the catalyst layer forming step is performed by applying a catalyst to the surface of the release film and attaching the release film formed with the catalyst layer to one side of the fuel electrode and the air electrode to form a catalyst layer can do.

The pressure-sensitive adhesive is preferably used, and the thickness of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer formed by transferring the pressure-sensitive adhesive is preferably 1 μm to 2 μm.

In addition, in order to achieve the object of the present invention, the polymer electrolyte fuel cell is a polymer electrolyte fuel cell manufactured according to the manufacturing method described above.

The polymer electrolyte fuel cell of the present invention includes a fuel electrode having a first catalyst layer formed on one side, an air electrode having a second catalyst layer formed on one side thereof, an electrolyte membrane formed between the fuel electrode and the air electrode, and an adhesive between the first catalyst layer and the electrolyte membrane A first pressure-sensitive adhesive layer formed by transferring is positioned, and a second pressure-sensitive adhesive layer formed by transferring an adhesive between the second catalyst layer and the electrolyte membrane is positioned to include a bonded membrane-electrode assembly.

Unlike the method for manufacturing a polymer electrolyte fuel cell using the pressure-sensitive adhesive transfer of the present invention, the conventional membrane-electrode assembly manufacturing method that does not apply an adhesive has high thermal conductivity for temperature transfer, and a heavy press to apply a high load. A roll made of a metal material is applied, which makes it difficult to obtain uniformity of press pressure and heat conduction, and thus it is difficult to secure repeatability and uniformity of the membrane-electrode assembly. In addition, when excessive pressure is applied, the electrode may be easily broken due to a springback phenomenon of the electrode subjected to pressure. In addition, it may be necessary to design a relatively large size of the electrode (positive electrode for H+ batteries, -OH batteries) that accommodates ions that play a mediating role in charge transfer. When excessive pressure is applied to prevent damage, the electrode cracks and edge-failure of the electrolyte membrane is accelerated due to the anode and cathode of different sizes.

However, in the present invention, unlike the conventional method for manufacturing a membrane-electrode assembly, the electrode and the electrolyte membrane can be sufficiently adhered to the electrode and the electrolyte membrane with a low-pressure press such as a rubber material with low heat transfer efficiency even at room temperature without applying a separate temperature. There is an effect that the manufacturing process efficiency can be improved by selecting the selection flexibly.

In addition, the performance of the polymer electrolyte fuel cell manufactured by the method for manufacturing the polymer electrolyte fuel cell using the pressure-sensitive adhesive transfer has the effect of exhibiting a power density corresponding to the performance of the membrane-electrode assembly manufactured according to the existing manufacturing method.

1 is a flowchart of a Catalyst-Coated Membrane (CCM) process.
2 is a flowchart of a Catalyst-Coated Substrate (CCS) process.
3 is a flowchart of a decal transfer process.
4 is a flowchart of a CCS process using pressure-sensitive adhesive transfer.
5 is a flowchart of a transfer (Decal Transfer) process using pressure-sensitive adhesive transfer.
6 is a schematic diagram showing the structure of the membrane-electrode assembly manufactured by the manufacturing method using the pressure-sensitive adhesive transfer of the present invention.
7 is a schematic diagram showing the structure of a membrane-electrode assembly according to a conventional manufacturing method.
8 shows the performance of a polymer electrolyte fuel cell membrane-electrode assembly manufactured using pressure-sensitive adhesive transfer according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying illustrative drawings, and these embodiments are examples, and those of ordinary skill in the art to which the present invention pertains may be implemented in various different forms. Examples are not limited.

The method for manufacturing a polymer electrolyte fuel cell of the present invention includes a polymer electrolyte membrane, a fuel electrode as an anode as an electrode, and an air electrode as a cathode, and prepares a membrane-electrode assembly by bonding the electrode and the electrolyte membrane.

4 is a flowchart of a process for a CCS method using a pressure-sensitive adhesive transfer according to an embodiment of the present invention.

The CCS method using the pressure-sensitive adhesive transfer is similar to the Catalyst-Coated Substrate (CCS) method shown in FIG. 2, but as shown in FIG. 4, after the electrode is manufactured, the electrode and the electrolyte membrane are pressed with a press. Lamination (S240) ), transferring the pressure-sensitive adhesive onto the upper surface of the catalyst layer of the electrode (S217 and S237).

In FIG. 4, the steps (S217, S237) of transferring the adhesive are steps S211 to S216 or S231 to S236 to manufacture a wide jumbo roll electrode and then slit in the process direction (Machine Direction, MD). The anode and the air electrode, respectively. The adhesive is transferred and attached to the surface of the

As the adhesive, a pressure sensitive adhesive (PSA) may be used. The pressure-sensitive adhesive is also referred to as a pressure-sensitive adhesive, and is a viscoelastic material and refers to an adhesive that is applied to an adhesive surface by pressure and the adhesive material acts when pressure is applied. As the pressure-sensitive adhesive, it is preferable to use an acrylic adhesive in which 2-ethylhexyl acrylate and n-butyl acrylate are applied as monomers.

For example, a film in which an acrylic pressure-sensitive adhesive is thinly applied to a thickness of 1 μm to 2 μm on the surface of a substrate of a PET film whose transfer efficiency is improved through silicone treatment may be used. If necessary, the adhesive film may be perforated to minimize the adhesive area between the electrode and the electrolyte membrane by the adhesive.

The electrode including the support to which the pressure-sensitive adhesive is transferred is adhered by performing lamination (S240) on both sides of the unwound electrolyte membrane that is not cut after being cut.

In the method for manufacturing a polymer electrolyte fuel cell using the pressure-sensitive adhesive transfer of the present invention, the process of manufacturing a membrane-electrode assembly by bonding an electrode and an electrolyte membrane. can be applied. In addition, the size of the roll can be applied even if it is relatively smaller than the press roll used when manufacturing the existing membrane-electrode assembly.

The type of material constituting the membrane-electrode assembly in the polymer electrolyte fuel cell is not particularly limited as long as it is commonly used in the art.

For example, the support used in the CCS method may be carbon paper or carbon cloth.

As the electrode of the membrane-electrode assembly, the catalyst used for the anode is hydrogen, alcohol, ammonia, liquid organic hydrogen carrier (LOHC), sodium borohydride (NaBH ₄ ), and other fuels that can be used in fuel cells. It is a platinum-based catalyst that can promote the oxidation reaction of

The catalyst used for the cathode as the electrode of the membrane-electrode assembly is a platinum-based catalyst such as Pt, PtNi, PtCo, PtFe, or PtPd, and may include a catalyst capable of accelerating the reduction of oxygen.

The electrolyte membrane positioned between the anode and the cathode may be a polyelectrolyte membrane.

Alternatively, the electrolyte membrane may be an ion exchange membrane. The ion exchange membrane may be a proton exchange membrane (PEM), an anion exchange membrane (AEM), a cation exchange membrane (CEM), or a combination thereof. The electrolyte membrane may selectively permeate cations, anions, or these including hydrogen ions.

5 is a flowchart of a process for a decal transfer method using a pressure-sensitive adhesive transfer according to an embodiment of the present invention.

The decal transfer method is also similar to the decal transfer method shown in FIG. 3, but as shown in FIG. 5, after the electrode is manufactured, the electrode and the electrolyte membrane are pressed with a presser for lamination (Lamination, S340). ), transferring the pressure-sensitive adhesive onto the upper surface of the catalyst layer of the electrode (S317 and S337).

Before performing lamination in the CCS method of FIG. 4 and the decal transfer method of FIG. 5, cutting the anode on which the first pressure-sensitive adhesive layer is formed and the cathode on which the second pressure-sensitive adhesive layer is formed to an appropriate size may be further included can

6 is a schematic diagram showing the structure of the membrane-electrode assembly manufactured by the manufacturing method using the pressure-sensitive adhesive transfer of the present invention.

As shown in FIG. 6 , in the membrane-electrode assembly manufactured by the manufacturing method using the pressure-sensitive adhesive transfer of the present invention, an anode 11 having a first catalyst layer 13 formed on one side thereof, and a second catalyst layer 14 on one side thereof The cathode 12, the electrolyte membrane 15 formed between the anode 11 and the cathode 12, and the first catalyst layer 13 and the electrolyte membrane 15 formed by transferring an adhesive A pressure-sensitive adhesive layer 16 is positioned, and a second pressure-sensitive adhesive layer 17 formed by transferring a pressure-sensitive adhesive between the second catalyst layer 14 and the electrolyte membrane 15 is included, and the first pressure-sensitive adhesive layer 16 and the second pressure-sensitive adhesive layer 16 are included. Since the pressure-sensitive adhesive layer such as the pressure-sensitive adhesive layer 17 is present, adhesion is possible even at a room temperature of about 15° C. to 25° C. without a separate temperature application and with a relatively low pressure.

7 is a schematic diagram showing the structure of a membrane-electrode assembly according to the existing manufacturing method. As shown in FIG. 7, in the case of the membrane-electrode assembly according to the conventional manufacturing method shown in FIGS. 1 to 3, which does not transfer the adhesive, the anode 21 on which the first catalyst layer 23 is formed, the second on one side Catalyst layer 24 is the cathode 22, the electrolyte membrane 25 formed between the fuel electrode 21 and the cathode 22 is positioned, and there is no pressure-sensitive adhesive layer, so for lamination adhesion, a press made of a heavy metal roll is used. Application of relatively high temperature and high pressure as well as the time required for adhesion was required.

In order to confirm the performance of the polymer electrolyte fuel cell manufactured using the pressure-sensitive adhesive transfer according to an embodiment of the present invention, the polymer electrolyte fuel cell was prepared with a membrane-electrode assembly with an electrode area of 5 cm ² , and the anode at a single cell temperature of 80° C. Hydrogen and air were supplied to the cathode and the cathode at flow rates of 200 sccm and 500 sccm, respectively. Back pressure was set at 20 psig, respectively, and was evaluated under full humidification conditions, and the results are shown in FIG. 8 .

As shown in FIG. 8 , it was confirmed that the polymer electrolyte fuel cell manufactured using the pressure-sensitive adhesive transfer obtained a single cell output of 800 mW/cm ² or more. This corresponds to the performance of the membrane-electrode assembly according to the existing manufacturing method, and it can be seen that a polymer electrolyte fuel cell using adhesive transfer can be manufactured.

11: fuel electrode
12: air electrode
13: first catalyst layer
14: second catalyst layer
15: electrolyte membrane
16: first pressure-sensitive adhesive layer
17: second pressure-sensitive adhesive layer
21: fuel electrode
22: air electrode
23: first catalyst layer
24: second catalyst layer
25: electrolyte membrane

Claims (8)

forming a catalyst layer by applying a catalyst to one side of the anode to form a first catalyst layer, and applying a catalyst to one side of the cathode to form a second catalyst layer;
a pressure-sensitive adhesive layer forming step of transferring a pressure-sensitive adhesive to an upper surface of the first catalyst layer to form a first pressure-sensitive adhesive layer, and transferring the pressure-sensitive adhesive to an upper surface of the second catalyst layer to form a second pressure-sensitive adhesive layer; and
and placing an electrolyte membrane between the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer and pressing with a press to form a membrane-electrode assembly. According to claim 1,
The catalyst layer forming step includes forming the catalyst layer using any one method selected from a Catalyst-Coated Membrane (CCM) method, a Catalyst-Coated Substrate (CCS) method, and a Decal Transfer method. Battery manufacturing method. According to claim 1,
The catalyst layer forming step is a method for manufacturing a polymer electrolyte fuel cell, characterized in that the catalyst layer is formed by directly applying a catalyst to one side of the fuel electrode and the cathode. According to claim 1,
The catalyst layer forming step is a method of manufacturing a polymer electrolyte fuel cell, characterized in that by applying a catalyst to the surface of the support and attaching the support on which the catalyst layer is formed to one side of the fuel electrode and the cathode. According to claim 1,
The catalyst layer forming step is a method of manufacturing a polymer electrolyte fuel cell, characterized in that by applying a catalyst to the surface of the release film and attaching the release film on which the catalyst layer is formed to one side of the fuel electrode and the cathode. According to claim 1,
The method for manufacturing a polymer electrolyte fuel cell, characterized in that the pressure-sensitive adhesive is a pressure-sensitive adhesive. According to claim 1,
The thickness of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a method of manufacturing a polymer electrolyte fuel cell, characterized in that 1㎛ to 2㎛. A polymer electrolyte fuel cell manufactured according to the manufacturing method of any one of claims 1 to 7.

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