Heat treatment process for a membrane electrode assembly for a fuel cell

Abstract

Heat treatment process for a membrane electrode assembly (MEA) of a fuel cell, wherein the heat treatment process comprises: Placing a current plate on a surface of the MEA or on a surface of an assembly consisting of an MEA and a gas diffusion layer (GDL) (104); and Performing a heat treatment on a surface or inside the current plate by applying a voltage to the current plate, wherein the current plate has a first conductive section (P1) arranged in the center of the current plate, a pair of insulating sections arranged on both sides of the first conductive section (P1) and a second conductive section (P2) arranged on one outside of the pair of insulating sections, and wherein the first conductive section (P1) and the second conductive section (P2) are configured to apply different types of stress in order to perform heat treatment at different locations.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a heat treatment method and an apparatus for a heat treatment method for a membrane electrode assembly for a fuel cell, and in particular to a heat treatment method for a membrane electrode assembly to improve the durability of the membrane electrode assembly and a heat treatment apparatus for carrying out the same. BACKGROUND

[0002] Fuel cells are energy generation systems that convert the chemical energy of a fuel into electrical energy through an electrochemical reaction in a stack, without converting the chemical energy into heat through combustion.

[0003] Such a fuel cell can not only provide electrical energy for industrial and domestic applications and for powering vehicles, but can also be used as a voltage source for small electrical / electronic products, especially mobile devices.

[0004] Currently, a polymer electrolyte membrane fuel cell (PEMFC), also known as a proton exchange membrane fuel cell, is used as an energy source to power a vehicle.

[0005] The PEMFC has a lower operating temperature, higher efficiency, higher current density and higher power density, a shorter start-up time and responds faster to load changes than other fuel cell types and is therefore widely suitable as a voltage source for mobile devices.

[0006] The PEMFC contains a membrane electrode assembly (MEA) formed by applying catalyst electrode layers, on which an electrochemical reaction takes place, to both sides of the polymer electrolyte membrane through which hydrogen ions move; a gas diffusion layer (GDL) for the uniform distribution of the reaction gases and for the transfer of the generated electrical energy; a seal and fastening mechanism to seal the reaction gases and cooling water and to maintain the prescribed fastening pressure; and a bipolar plate for transporting the reaction gases and cooling water.

[0007] Furthermore, a fuel cell system used in a fuel cell vehicle includes a fuel cell stack for generating electrical energy by means of an electrochemical reaction of the reaction gases (hydrogen as fuel and oxygen as oxidant), a hydrogen supply device for supplying hydrogen as fuel to the fuel cell stack, an air supply device for supplying oxygen-containing air to the fuel cell stack, a heat and water management system for controlling the operating temperature of the fuel cell stack and for performing a water management function, and a fuel cell controller for controlling the overall operation of the fuel cell system.

[0008] In a typical fuel cell system, the hydrogen supply system includes a hydrogen storage unit (hydrogen tank), a regulator, a hydrogen pressure regulating valve, and a hydrogen recirculation system, while the air supply system includes an air blower and a humidifier. The heat and water management system includes a coolant pump, a water reservoir, and a radiator.

[0009] Fig. Figure 1 shows a procedure for manufacturing a typical GDL-MEA assembly. As in Fig. Figure 1 shows a membrane electrode assembly (MEA) produced by forming electrodes (cathode, anode) on both surfaces of an electrolyte membrane and by subsequently applying intermediate sealing films.

[0010] The MEA produced in this way undergoes heat treatment by thermocompression to improve its durability. The heat-treated MEA has high durability, but exhibits reduced performance due to its deterioration.

[0011] As in Fig. In Figure 1, the gas diffusion layers (GDL) are bonded to both sides of the finished MEA. The bonding is done as shown in [reference to diagram]. Fig. The body shown in Figure 1 is referred to as a GDL-MEA assembly. Bonding methods for GDL-MEAs include thermocompression and the use of an adhesive. However, bonding by thermocompression may not be applicable depending on the material or processing of the MEA. When using an adhesive, product yield is problematic.

[0012] Heat treatment methods for a membrane electrode assembly (MEA) of a fuel cell are already known from DE 10 2008 025 928 A1 and DE 10 2010 035 949 A1, each comprising the following heat treatment method: placing a current plate on a surface of the MEA or on a surface of an assembly consisting of an MEA and a gas diffusion layer (GDL); and performing a heat treatment on a surface or inside the current plate by applying a voltage to the current plate. OVERVIEW OF THE REVELATION

[0013] The present disclosure has been developed in an effort to solve the problems of related technology described above, and it is the object of the present disclosure to provide a heat treatment method and an apparatus for a membrane electrode assembly which can ensure the durability of the membrane electrode assembly and prevent deterioration of performance due to deterioration of condition by carrying out a heat treatment of the membrane electrode assembly under different conditions depending on the physical properties of the respective components of the membrane electrode assembly.

[0014] The problem is solved by a heat treatment method having the features of claim 1 and a heat treatment device having the features of claim 9. Advantageous further developments are found in the dependent claims.

[0015] According to an embodiment of the present disclosure, a heat treatment method for a membrane electrode assembly (MEA) for a fuel cell comprises placing a current plate on a surface of an MEA or on a surface of an assembly of the MEA and a gas diffusion layer (GDL), and performing a heat treatment on the surface or inside the current plate by applying a voltage to the current plate. The current plate has a first conductive section located in the center of the current plate, a pair of insulating sections arranged on either side of the first conductive section, and a second conductive section arranged on an outside of the pair of insulating sections. The first conductive section and the second conductive section are configured to apply different types of voltages to perform a heat treatment at different locations.

[0016] The current plate can be placed on the MEA, and the heat treatment can be performed on an electrode section of the MEA by applying a direct current (DC) voltage or a DC voltage pulse to the MEA.

[0017] The current plate can be placed on the MEA, and the heat treatment is carried out on an electrolyte membrane of the MEA by applying an alternating voltage (AC) to the MEA.

[0018] The current plate can be placed on the assembly of the MEA and the GDL, and the heat treatment can be performed on an interface between the MEA and the GDL by applying an alternating voltage (AC) pulse to the MEA-GDL assembly.

[0019] The current plate can be a current plate for a pressing operation and apply voltage to the surface of the MEA or the assembly of MEA and GDL while it is pressed onto the surface.

[0020] The heat treatment can be carried out either on the electrode section of the MEA, on an electrolyte membrane or on an interface between the GDL and the MEA by means of the voltage applied by the first conductive section, wherein the heat treatment can be carried out either on the electrode section, the electrolyte membrane or the interface by means of the voltage applied by the second conductive section, except for the component where the heat treatment is carried out by means of the voltage applied to the first conductive section.

[0021] According to an embodiment of the present disclosure, a heat treatment device for a membrane electrode assembly (MEA) for a fuel cell comprises a first electrically conductive press for pressing the MEA or an assembly consisting of the MEA and the gas diffusion layer (GDL), a feeding device configured to feed the MEA or the assembly consisting of the MEA and the GDL to the first electrically conductive press, and a voltage supply configured to apply a voltage to the first electrically conductive press, wherein the heat treatment is carried out on a surface or inside the MEA or the assembly consisting of the MEA and the GDL by applying a voltage to the MEA or the assembly consisting of the MEA and the GDL.The current plate has a first conductive section located in the center of the current plate, a pair of insulating sections located on either side of the first conductive section, and a second conductive section located on one outside of the pair of insulating sections, and the first conductive section and the second conductive section are configured to apply different types of voltage to perform heat treatment at different locations.

[0022] The first electrically conductive press can include a current plate for a pressing operation, wherein the current plate is configured to be in contact with an object to be pressed, the current plate applying the voltage supplied by the power supply to the surface of the MEA or the assembly of the MEA and the GDL while applying pressure to the surface.

[0023] The feeding device can be a roll-to-roll type feeding device and may include a feed roller and a winding roller.

[0024] The feeding device may also include one or more movable buffer rollers to maintain constant tension.

[0025] The heat treatment device may also include a cutting device for cutting the MEA or the assembly consisting of the MEA and the GDL, which has been heat treated by the first electrically conductive press, to a predetermined size.

[0026] The heat treatment device may also include a transport unit for transporting the MEA cut off by the cutting device or the MEA-GDL assembly from the

[0027] The heat treatment device may further include a second electrically conductive press configured to press the MEA or MEA-GDL assembly supplied by the transport unit, and a second power supply configured to apply a voltage to the second electrically conductive press, wherein heat treatment of the MEA or MEA-GDL assembly is carried out by applying the voltage to the second electrically conductive press.

[0028] The feeding device may include a transport robot arm.

[0029] Other aspects and embodiments of the disclosure are explained below.

[0030] It is understood that the term "vehicle" or "vehicle-related" or other similar terms used herein generally refer to motor vehicles, such as passenger cars, including sports utility vehicles (SUVs), buses, trucks, various commercial vehicles, personal watercraft including various boats and ships, aircraft, and the like, and also includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles (rechargeable from an electrical outlet), hydrogen-powered vehicles, and other vehicles powered by alternative fuels (e.g., fuels derived from resources other than petroleum). As used herein, a hybrid vehicle is a vehicle with two or more sources of propulsion, e.g., vehicles powered by both gasoline and electric motors.

[0031] The above and other features of the invention are explained below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other features of the present disclosure will now be described in detail with reference to certain embodiments shown in the accompanying drawings, which serve only as examples and are not intended to limit the present disclosure; they show: Fig. 1. A procedure for manufacturing a typical GDL-MEA assembly; Fig. 2a a perspective view of the structure of an MEA for a fuel cell; Fig. 2b a sectional view along line AA' in Fig. 2a; Fig. 3a a perspective view of the structure of a GDL-MEA for a fuel cell; Fig. 3b a sectional view along line BB' in Fig. 3a; Fig. 4 a concept diagram of the heat treatment of the outside (electrode section) of an MEA; Fig. 5 the direct current (DC) pulse applied during the heat treatment of the outside (electrode section) of an MEA; Fig. 6 a concept diagram of the heat treatment of the interior (electrolyte membrane) of an MEA; Fig. 7 the alternating voltage (AC) applied during the heat treatment of the interior (electrolyte membrane) of an MEA; Fig. 8 a concept diagram of the heat treatment of the interface of the GDL-MEA; Fig. 9 the alternating voltage (AC) pulse applied during the heat treatment of the GDL-MEA interface; Fig. 10 a roll-to-roll manufacturing device according to an embodiment of the present disclosure; Fig. 11 a manufacturing device of the plate type according to another embodiment of the present disclosure; and Fig. 12a and Fig. 12b a structure of a press stream plate according to an embodiment of the present disclosure, wherein Fig. 12a a top view and Fig. 12b is a section view along line CC'.

[0033] It is understood that the accompanying drawings are not necessarily to scale, as they show a somewhat simplified representation of the various preferred features that illustrate the principles underlying the invention. The specific design features disclosed herein, which include, for example, specific dimensions, orientations, locations, and shapes, are partly determined by the particular intended application and the operating environment.

[0034] In the figures, identical reference symbols denote the same or equivalent parts of the present revelation in the different figures of the drawing. DETAILED DESCRIPTION

[0035] The exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings, so that the person skilled in the art can easily implement the present disclosure.

[0036] The advantages and features of the present disclosure, as well as the methods for achieving them, will become apparent from the detailed description of embodiments in conjunction with the accompanying drawings.

[0037] However, the present disclosure is not limited to the embodiments disclosed herein, but can be implemented in various forms. The embodiments are only examples, and the present disclosure should be defined by the scope of protection of the claims.

[0038] Furthermore, the description of the present disclosure omits a detailed explanation of related technologies and the like if it can be assumed that otherwise the subject matter of the present disclosure would become unclear.

[0039] The present disclosure provides a technology for effectively carrying out a heat treatment between the respective components in the manufacture of a membrane electrode assembly (MEA) used in a fuel cell and a GDL-MEA formed by bonding the MEA with a gas diffusion layer (GDL).

[0040] In particular, the present disclosure describes the application of different heat treatment conditions to each component of the GDL-MEA, depending on the objects inside and outside the MEA that are to undergo heat treatment. Furthermore, the different heat treatment conditions are applied in a single process for simplification purposes, where possible. Within the scope of this description, the membrane electrode assembly is also referred to as an MEA. In this description, the gas diffusion layer is also referred to as a GDL, and consequently, the assembly consisting of the membrane electrode assembly and the gas diffusion layer can be referred to as a GDL-MEA or GDL-MEA assembly, with these terms being synonymous.

[0041] In the following, a heat treatment process and a device for a membrane electrode assembly for a fuel cell according to an embodiment of the present disclosure are described in detail with reference to the accompanying drawings.

[0042] Fig. 2a is a perspective view of the structure of an MEA for a fuel cell, and Fig. 2b is a sectional view along line AA' in Fig. 2a.

[0043] Fig. Figure 2a shows a membrane electrode assembly (MEA) before bonding to the gas diffusion layers (GDLs) in Fig. 1. As in Fig. Figure 2b shows an MEA with an electrolyte membrane 101 as a dielectric and an electrode section 102 with a dielectric and a conductor, as well as an intermediate seal 103, which is a dielectric and is positioned at the edge as shown in the Fig. 2a and Fig. 2b shown.

[0044] The Fig. 3a and Fig. Figure 3b shows the structure of a GDL-MEA assembly formed by bonding a GDL and an MEA together.

[0045] The structure of Fig. 3a and Fig. 3b is achieved by gluing the GDL 104 onto the MEA of Fig. 2a formed. Therefore, the cross-section of the structure is as shown in Fig. Figure 3b shows a stacking structure resulting from stacking the GDL 104, which is a conductor, on the electrode section 102.

[0046] In one embodiment of the present disclosure, a current plate P is located on the surface of the MEA with the cross-sectional structure as shown in Fig. 2a shown or on the GDL-MEA with the cross-sectional structure as in Fig. 3b is arranged, and voltage is applied to the current plate P to carry out the heat treatment on the surface or inside the plate.

[0047] However, to improve durability and prevent deterioration, different heat treatment conditions can be applied depending on the section to be heat treated. In one embodiment of the present disclosure, the heat treatment is therefore carried out in a different way depending on the location where the heat treatment is to be performed.

[0048] In this embodiment in particular, the sections to be subjected to heat treatment are divided into the electrode section 102 of the MEA, the electrolyte membrane of the MEA and the interface between the GDL 103 and the MEA, and a different heat treatment procedure is prescribed for each section.

[0049] The heat treatment process for each section is described below.

[0050] Fig. 4 is a concept diagram of the heat treatment of the outside (electrode section) of the MEA and Fig. Figure 5 shows the direct current (DC) pulse applied during the heat treatment of the outer surface (electrode section) of the MEA. Herein, MEA means the electrode section 102, unless otherwise specified, and the interior of the membrane electrode assembly refers to the electrolyte membrane 101, unless otherwise specified.

[0051] According to the present disclosure, a DC voltage or a DC voltage pulse is used to sinter the electrode section 102 during its heat treatment. Heat generation by a conductor through which a constant current flows is called Joule heating, and the heat value (Q) of Joule heating is given by the following equation. Q = I 2 Rt (Q: heat value, I: current, R: resistance, t: time)

[0052] When using direct current, the electrode is heat-treated by Joule heating. However, when a DC pulse is applied, an additional sintering effect occurs due to sparking at the interface between electrode particles, as in... Fig. 4 shown. Fig. Figure 5 shows the voltage of the DC pulse source. The heat treatment conditions can be set differently depending on the specifications of the membrane electrode assembly and can be changed by adjusting the duty cycle, voltage level, and the like. In contrast to Fig. A DC voltage can be applied to terminal 5.

[0053] In one embodiment of the present disclosure, the current plate P, consisting of a conductor, is positioned on the MEA to apply voltage to the MEA. The current plate P is connected to a DC source or a DC pulse source to perform the heat treatment of the electrode section 102 of the MEA.

[0054] Fig. Figure 6 is a concept diagram of the heat treatment of the interior (electrolyte membrane) of the MEA, and Fig. Figure 7 shows the alternating voltage applied during the heat treatment of the interior (electrolyte membrane) of the MEA.

[0055] To carry out the heat treatment inside the MEA, i.e., the electrolyte membrane 101, the present disclosure proposes a heat treatment method using an AC source. When an alternating voltage is applied to a dielectric, the dielectric material vibrates according to the electric field, and the vibrations are converted into heat. That is, if the alternating voltage is applied to both surfaces of the electrolyte membrane at a frequency corresponding to the resonant frequency of the electrolyte membrane, the electrolyte membrane is heated. As a result, the heat treatment is concentrated on the electrolyte membrane and the interface between the electrolyte membrane and the electrode.

[0056] The power plate P is arranged on the MEA as shown in Fig. Figure 6 shows that the electrolyte membrane 101 is activated by applying an alternating voltage to the MEA as shown in Figure 6. Fig. 7 shown heat-treated.

[0057] The conditions for applying the voltage can be changed according to the MEA specifications. Furthermore, the frequency (1 / period) of the alternating voltage is set to the resonant frequency of the electrolyte membrane 101 in order to heat the electrolyte membrane 101 as described above.

[0058] Fig. Figure 8 is a concept diagram of the heat treatment of the GDL-MEA interface, and Fig. Figure 9 shows an AC pulse applied during the heat treatment of the GDL-MEA interface.

[0059] According to the present disclosure, an AC pulse is used to bond the GDL-MEA interface. An AC pulse voltage higher than or equal to a breakdown voltage is applied between the GDL and the MEA electrode section. This results in local bonding, as a spark is generated at the interface between the GDL and the MEA electrode. The charge delivered by a pulse is determined by the capacitance of the electrode. The charge delivered by a pulse is set to be lower than or equal to the capacitance of the MEA.

[0060] As in Fig. Figure 8 shows that, to carry out the heat treatment of the GDL-MEA interface, an AC pulse is applied from the current plate P, which is arranged on the assembly of the MEA and the GDL 103, to the assembly of the MEA and the GDL 103.

[0061] Since this involves an alternating voltage that is higher than or equal to a breakdown voltage as in Fig. As shown in diagram 9, the bonding is achieved by a spark that ignites a portion of the interface as shown in diagram 9. Fig. 8 is generated.

[0062] Another feature of the present disclosure is that at least some of the different heat treatment processes described above are carried out simultaneously.

[0063] The manufacturing device for this process is in the Fig. 10 to 12 are shown.

[0064] Fig. Figure 10 shows in particular a manufacturing device of a roll-to-roll type according to one embodiment of the present disclosure, and Figure 10 shows a roll-to-roll manufacturing device according to another embodiment of the present disclosure. Fig. Figure 12 shows a structure of a press stream plate according to an embodiment of the present disclosure.

[0065] The roll-to-roll type manufacturing device of Fig. 10 and the manufacturing device of the plate type of Fig. 11 can be used separately, or the two devices can be installed in series.

[0066] For example, a manufacturing device of the roll-to-roll type can be used. Fig. 10 manufactured MEAs for the manufacturing device of the plate type of Fig. 11 are transported, and then a subsequent process can be carried out by the device of Fig. 11 will be executed.

[0067] In the roll-to-roll process, a raw material is wound into a roll and fed along a specific path, and the processed product is wound into a roll and stored. As in Fig. Figure 10 shows the MEA rolled into film form being fed in from the feed side. The fed MEA passes through a centrally located electrically conductive press 206. When the position sensor confirms that the MEA is correctly positioned, the electrically conductive press compresses both sides of the MEA. During processing by the electrically conductive press, the transport of the material is stopped, and the voltage acting on the material is kept constant during the period between the stop and restart of the transport. The processed product is then moved along the path again, wound up, and stored.

[0068] Since the MEA in particular is manufactured using a roll-to-roll process, the device contains Fig. 10 a feeding device with a feed roller 201 on the feed side for feeding an output MEA and a winding roller 202 for winding the MEA, in which the heat treatment is completed.

[0069] Furthermore, an electrically conductive press 206 for heat treatment is provided between the feed roller 201 and the winding roller 202. The electrically conductive press 206 serves to press the MEA or the assembly consisting of the MEA and the GDL. In addition, the roll-to-roll manufacturing device according to this embodiment includes a power supply 205 for supplying power to the electrically conductive press 206.

[0070] The power supply 205 provides voltage to the MEA, which is arranged on the electrically conductive press 206, or to the assembly consisting of the MEA and the GDL. The power supply 205 performs a heat treatment on the surface of the MEA, inside the MEA, or on the interface between the GDL and the MEA.

[0071] The electrically conductive press 206 includes a current plate P for press contact with an object to be pressed, and the current plate P for pressing applies a voltage to the surface of the MEA or to the assembly of the MEA and the GDL while pressing the surface.

[0072] In one embodiment of the present disclosure, a current plate for the pressing operation is provided with a structure as described in the Fig. 12a and Fig. Figure 12b shows how different heat treatment processes can be carried out simultaneously.

[0073] In particular, the current plate for the pressing operation includes a first conductive section P1 arranged in the middle, a pair of insulating sections arranged on both sides of the first conductive section P1, and a second conductive section P2 arranged on the outside of the pair of insulating sections.

[0074] This means that, as in Fig. As shown in Figure 12a, a pair of insulating sections is formed near both side edges of the current plate for the pressing operation, such that the surface of the current plate is divided into three parts by the insulating sections. The positions of the insulating sections can be modified as appropriate according to the type of MEA or GDL-MEA to be subjected to heat treatment. The positions of the insulating sections are limited to the position of the object to be heat treated.

[0075] In this structure, the top and bottom sides are divided into Fig. 12a, i.e., the second conductive sections P2 near the two side edges of the sections defined by the insulating sections are used for the heat treatment of the electrode section 102 as in Fig. 4 shown. That is, as in Fig. Figure 4 shows the heat generated when current flows to the conductor of the electrode section during the heat treatment of the electrode section, with the current plates on both sides configured as the (+) and (-) electrodes.

[0076] On the other hand, the first conductive section P1, located in the middle and defined by the insulating sections, can be subjected to a heat treatment carried out by applying a voltage to the entire central section, as in Fig. 6 or Fig. 8 is shown.

[0077] Since the current plate is configured for the pressing operation as described above, different voltages are applied through the first conductive section P1 and the second conductive section P2. Therefore, different sections of the MEA or GDL-MEA can be heat-treated.

[0078] The manufacturing device according to this embodiment further includes one or more movable buffer rollers 203, 204 to maintain the tension in the feeding device during the pressing operation. That is, the buffer rollers 203 and 204 themselves rotate during the pressing operation. The buffer rollers 203 and 204 thus move to prevent movement of the membrane electrode assembly or the like during the pressing operation, so that the tension in the feeding device is kept constant.

[0079] Furthermore, a cutting device for cutting the MEA or the assembly consisting of the MEA and the GDL to a predetermined size after heat treatment by the electrically conductive press 206 can be additionally provided. The cutting device can be used in place of the winding roller 202. Fig. 10 can be installed and can provide an MEA in a cut form similar to the final product instead of the roll-shaped MEA intermediate material.

[0080] A transport unit can be provided for transporting the MEA cut by the cutting device or the cut assembly from the MEA and GDL. The transport unit can be a robot arm as shown in Fig. 11 is shown and is preferably used for transporting the MEA cut by the cutting device to the device of Fig. 11.

[0081] The device of Fig. 11 can be used with the device of Fig. 10 can be connected in series or used independently and can use the same electrically conductive press 304 and power supply 303 to apply a voltage to the current plate P as in Fig. 10 included. That is, the manufacturing device of the plate type according to Fig. 11 can be installed independently to perform the heat treatment of the MEA or the GDL-MEA and in some cases can be used with the device of Fig. 10 can be combined.

[0082] The manufacturing device of the plate type of Fig. The assembly 11 can include a feed-side transport robot arm 301 for feeding the MEA or GDL-MEA to the electrically conductive press 304 and another transport robot arm 302 for receiving the heat-treated MEA or GDL-MEA. The transport robot arm 301, 302 can include a suction holder for holding the MEA to be transported by suction.

[0083] For example, as in Fig. Figure 11 shows an object to be subjected to heat treatment, i.e., an object to be fed to the electrically conductive press 304, moved by the transport robot arm at the feed side of the electrically conductive press 206 and then heat-treated by the electrically conductive press 304. Afterwards, the heat-treated object is transported by the other transport robot arm to receive the heat-treated MEA or GDL-MEA.

[0084] As can be seen from the above description, the durability of the membrane electrode assembly can be improved and a deterioration in performance that may be caused by a possible deterioration of condition during heat treatment can be prevented according to embodiments of the present disclosure, which perform the heat treatment on each of the internal components of a membrane electrode assembly under heat treatment conditions that are set according to the internal components of the membrane electrode assembly.

[0085] Since, according to embodiments of the present disclosure, the heat treatment processes can be carried out simultaneously under different conditions in the pressing process, the production time and costs of the membrane electrode assembly can be reduced, and thus productivity can be improved.

Claims

[1] Heat treatment process for a membrane electrode assembly (MEA) of a fuel cell, wherein the heat treatment process comprises: Placing a current plate on a surface of the MEA or on a surface of an assembly consisting of an MEA and a gas diffusion layer (GDL) (104); and Performing a heat treatment on a surface or inside the current plate by applying a voltage to the current plate, wherein the current plate has a first conductive section (P1) arranged in the center of the current plate, a pair of insulating sections arranged on both sides of the first conductive section (P1) and a second conductive section (P2) arranged on one outside of the pair of insulating sections, and wherein the first conductive section (P1) and the second conductive section (P2) are configured to apply different types of stress in order to perform heat treatment at different locations. [2] Heat treatment method according to claim 1, wherein the current plate is arranged on the MEA and the heat treatment is carried out on an electrode section (102) of the MEA by applying a DC voltage or a DC pulse to the MEA. [3] Heat treatment method according to claim 1, wherein the current plate is arranged on the MEA and the heat treatment is carried out on an electrolyte membrane (101) of the MEA by applying an alternating voltage (AC) to the MEA. [4] Heat treatment method according to claim 1, wherein the current plate is arranged on the assembly of the MEA and the GDL (104) and the heat treatment is carried out on an interface between the MEA and the GDL (104) by applying an alternating voltage pulse (AC) to the assembly of the MEA and the GDL. [5] Heat treatment method according to claim 1, wherein the current plate serves to perform a pressing operation and applies the voltage to the surface of the MEA or the assembly of the MEA and the GDL (104) while pressing the surface. [6] Heat treatment method according to claim 1, wherein the heat treatment is carried out on an electrode section (102) of the MEA, an electrolyte membrane (101) and an interface between the GDL (104) and the MEA by means of the voltage applied by the first conductive section (P1), and wherein the heat treatment is carried out on the electrode section (102), the electrolyte membrane (101) and the interface by means of the voltage applied by the second conductive section (P2), except for the component in which the heat treatment is carried out by means of the voltage applied to the first conductive section (P1). [7] Heat treatment method according to claim 3, wherein the frequency of the alternating voltage is set to the resonance frequency of the electrolyte membrane (101). [8] Heat treatment method according to claim 4, wherein an electrical charge supplied by a pulse of the applied AC pulse is set to be lower than or equal to the capacitance of the MEA. [9] Heat treatment device for a membrane electrode assembly (MEA) for a fuel cell, the heat treatment device comprising: a first electrically conductive press (206) for pressing the MEA or an assembly consisting of the MEA and a gas diffusion layer (GDL) (104); a feeding device configured to feed the MEA or the assembly consisting of the MEA and the GDL (104) to the first electrically conductive press (206); and a power supply (205) configured to apply a voltage to the first electrically conductive press (206), wherein the heat treatment is carried out on a surface or inside the MEA or on the assembly of the MEA and the GDL (104) by applying the stress to the MEA or the assembly of the MEA and the GDL (104), wherein the current plate has a first conductive section (P1) arranged in the center of the current plate, a pair of insulating sections arranged on both sides of the first conductive section (P1) and a second conductive section (P2) arranged on one outside of the pair of insulating sections, and wherein the first conductive section (P1) and the second conductive section (P2) are configured to apply different types of stress in order to perform heat treatment at different locations. [10] Heat treatment device according to claim 9, wherein the first electrically conductive press (206) has a current plate for the pressing operation, wherein the current plate is in contact with an object to be pressed, and wherein the current plate applies the voltage provided by the power supply (205) to the surface of the MEA or to the assembly of the MEA and the GDL (104) while the surface is being pressed. [11] Heat treatment device according to claim 9, wherein the feeding device is a roll-to-roll feeding device and comprises a feed roller and a winding roller (202). [12] Heat treatment device according to claim 11, wherein the feed device further comprises one or more movable buffer rollers (203, 204) to maintain the tension in the feed device. [13] Heat treatment device according to claim 11, further comprising: a cutting device configured to cut the MEA or the assembly consisting of the MEA and the GDL (104) to a predetermined size, which has been heat-treated by the first electrically conductive press (206). [14] Heat treatment device according to claim 13, further comprising: a transport unit configured to transport the MEA cut by the cutting device or the assembly consisting of the MEA and GDL (104). [15] Heat treatment device according to claim 14, further comprising: a second electrically conductive press (304) configured for pressing the MEA transported by the transport unit or the assembly consisting of the MEA and the GDL (104); and a second power supply (303) configured to apply a voltage to the second electrically conductive press (304), wherein the heat treatment on the MEA or the assembly consisting of the MEA and the GDL (104) is carried out by applying the voltage to the second electrically conductive press (304). [16] Heat treatment device according to claim 9, wherein the feeding device has a transport robot arm (301, 302).

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