A method of packaging a single-sided frame film electrode structure

Abstract

The application belongs to the technical field of membrane electrode, and particularly relates to a packaging method of a single-frame electrode structure. The packaging structure comprises that a CCM is located on the upper surface of a single frame, the upper surface of the CCM is connected with an anode gas diffusion layer, the lower surface of the single frame is connected with a cathode gas diffusion layer, and a specific packaging method is provided. The application solves the defects of the existing packaging process, utilizes a single-frame structure to simplify the process, eliminates the frame pressing process, and greatly reduces the generation of frame bubbles and wrinkles.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of membrane electrode, and particularly relates to a packaging method of a single-side frame electrode structure. BACKGROUND

[0002] A fuel cell is a power generation device for directly converting chemical energy into electric energy through an electrochemical reaction, and has the characteristics of high energy conversion efficiency and environmental friendliness, and is considered as a preferred clean and efficient power generation technology in the 21st century. A membrane electrode is a place where an electrochemical reaction occurs, and chemical energy in fuel is directly converted into electric energy. The membrane electrode is a core component of a proton exchange membrane fuel cell, and the performance of the membrane electrode directly determines the service life of the cell. The current packaging method of a seven-in-one membrane electrode is as follows: first, an anode catalyst layer and a cathode catalyst layer are respectively sprayed on both sides of a proton exchange membrane to prepare a CCM; then a CCM is sealed by a glue-coated cathode frame and an anode frame; and finally, a cathode gas diffusion layer and an anode gas diffusion layer are bonded to the frame to form a membrane electrode. However, the packaging process needs multiple positioning and bonding, and the process is relatively complicated, which is difficult to mass-produce. SUMMARY

[0003] In view of the problems in the prior art, the application provides a packaging method of a single-side frame membrane electrode structure, which solves the defects of the existing packaging process, uses a single-side frame structure to simplify the process, and eliminates the frame pressing process, thereby greatly reducing the generation of frame bubbles and wrinkles.

[0004] To achieve the above technical purposes, the technical scheme of the application is as follows:

[0005] A packaging method of a single-side frame membrane electrode structure, comprising the following steps:

[0006] Step 1: preparing a CCM by using a proton exchange membrane, an anode catalyst layer and a cathode catalyst layer; pressing a single-layer frame by using a mold; and cutting a cathode gas diffusion layer and an anode gas diffusion layer;

[0007] Step 2: coating an adhesive or pasting a rubber strip on the edge of a center through hole on the top surface of the single-layer frame, and then bonding the CCM to the frame;

[0008] Step 3: coating an adhesive or pasting a rubber strip on the edge of the CCM on the frame, and the adhesive or rubber strip covers the edge of the CCM; the adhesive is made of a thermoplastic material or a thermosetting material, the thermoplastic material is one of polyethylene, polypropylene and aromatic polyamide, and the thermosetting material is epoxy resin or silicone resin;

[0009] Step 4, the adhesive or adhesive tape is coated on the edge of the cathode gas diffusion layer and the anode gas diffusion layer; then the anode gas diffusion layer, the CCM, the frame and the cathode gas diffusion layer are hot-pressed in order to obtain a single-frame electrode structure. The hot-pressing temperature is 120-150℃, the pressure is 0.1-2MPa, and the time is 0.1-5min.

[0010] The packaging structure comprises: the CCM is located on the upper surface of the single frame, and the upper surface of the CCM is connected with the anode gas diffusion layer, and the lower surface of the single frame is connected with the cathode gas diffusion layer. The CCM in the membrane electrode packaging structure is located on one side of the single frame and is fixed on the surface of the single frame, that is, there is a gap between the CCM and the cathode diffusion layer, and the gap is consistent with the thickness of the single frame, the CCM is connected with the anode gas diffusion layer through the adhesive of the edge, and based on the low gap spacing of the adhesive itself, the anode gas diffusion layer and the CCM form a no-buffer penetration, realizing the no-obstacle and no-buffer circulation when the gas is stable. The buffer zone between the CCM and the cathode gas diffusion layer ensures the stable diffusion effect of the cathode gas. The gas can form stable and comprehensive contact with the CCM, and there is no problem of local shielding, which provides the reaction uniformity, and the buffer zone has the gas concentration buffering effect, when the diffusion layer or the external gas source changes, the internal buffer layer concentration can form a stable transition, achieving the effect of slow change, increasing the anti-shock resistance of the membrane electrode.

[0011] The CCM is composed of a hydrophilic catalyst layer and a modified perfluorosulfonic acid proton exchange membrane, that is, the hydrophilic catalyst slurry is transferred to both sides of the modified perfluorosulfonic acid proton exchange membrane to form the CCM.

[0012] The modified perfluorosulfonic acid proton exchange membrane is a silica-modified perfluorosulfonic acid proton exchange membrane, and the preparation method of the silica-modified perfluorosulfonic acid proton exchange membrane comprises: a1, tetraethoxysilane is added to anhydrous ether to form a 60g / L solution; a2, the surface of the perfluorosulfonic acid proton exchange membrane is sprayed with a hydrochloric acid solution to form a liquid film, and is placed for 2h, and is dried to obtain an activated perfluorosulfonic acid proton exchange membrane, the pH of the hydrochloric acid solution is 5, and the spraying amount is 6mL / cm 2During the spraying process, the hydrochloric acid solution spray film is evenly distributed on the surface of the perfluorosulfonic acid proton exchange membrane, achieving a permeability effect. Furthermore, during the standing process, it promotes the complete activation of sulfonate ions. a3. The activated perfluorosulfonic acid proton exchange membrane is immersed in the solution and allowed to stand for 2 hours. After removal, it is dried to obtain a pre-modified perfluorosulfonic acid proton exchange membrane. The immersion temperature is 5℃, and the drying temperature is 50℃. a4. The pre-modified perfluorosulfonic acid proton exchange membrane is allowed to stand in a humid atmosphere for 2 hours, followed by constant temperature heat treatment to obtain... A perfluorosulfonic acid proton exchange membrane modified with nano-silica is described. The humid atmosphere is a mixture of nitrogen and water vapor, with water vapor accounting for 5% by volume. The static temperature is 40°C, and the isothermal heat treatment is performed at 100°C for 4 hours. This process utilizes an anhydrous diethyl ether solution of ethyl silicate to form a liquid film, and then removes the anhydrous diethyl ether by temperature to obtain a perfluorosulfonic acid proton exchange membrane with ethyl silicate adhering to it. Following hydrolysis and heat treatment, an in-situ reacted nano-silica modified perfluorosulfonic acid proton exchange membrane is obtained. The main component of the perfluorosulfonic acid proton exchange membrane is a copolymer of tetrafluoroethylene monomer and perfluorovinyl ether monomers with sulfonic acid groups.

[0013] The hydrophilic catalyst slurry is prepared by weighing a hydrophilic catalyst, a perfluorosulfonic acid resin solution and a dispersant in a mass ratio of 1:1:0.1 and dispersing them to form a homogeneous slurry. The hydrophilic catalyst is a platinum-carbon catalyst supported by hydroxyl-modified carbon material, and the platinum element content of the platinum-carbon catalyst is 6%. The dispersant is isopropanol, and the mass concentration of the perfluorosulfonic acid resin is 6%.

[0014] The platinum content in the CCM prepared by the above method is 0.4 mg / cm³. 2 .

[0015] This CCM utilizes a hydrophilic catalyst to form excellent water affinity, constructing a superior proton transport network to enhance the CCM's functionality. Simultaneously, the hydrophilicity of the nano-silica within the CCM enables self-contained transport on the exchange membrane surface, facilitating water molecule diffusion and achieving excellent catalytic effects. Furthermore, the CCM's inherent hydrophilicity and the gap structure between the diffusion membrane ensure minimal water molecule loss, enabling self-balancing under humidification conditions.

[0016] Meanwhile, the hydrophilicity of the hydrophilic catalyst layer and the modified perfluorosulfonic acid proton exchange membrane in the CCM can effectively form a hydrophilic proton network in the catalyst layer, and the hydrophilicity throughout the CCM promotes the hydrophilic migration of water molecules. Combined with the buffer zone between the CCM and the cathode gas diffusion layer, it can prevent water molecules from migrating to the cathode, thus achieving a unidirectional control effect.

[0017] As can be seen from the above description, the present invention has the following advantages:

[0018] 1. The present application solves the defects of the existing packaging process, uses a single-frame structure and a simple process, and does not need a frame pressing process, thereby greatly reducing the generation of frame bubbles and wrinkles.

[0019] 2. The components and compositions of the present application can be produced on automatic equipment, greatly improving production efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a packaging structure diagram of a single-frame membrane electrode in the embodiment of the present application. DETAILED DESCRIPTION

[0021] In combination Figure 1 , a specific embodiment of the present application is described in detail, but does not limit the claims of the present application.

[0022] Example 1

[0023] As shown in Figure 1 , a single-frame membrane electrode structure, the CCM is located on the upper surface of the single frame, and the upper surface of the CCM is connected with the anode gas diffusion layer, and the lower surface of the single frame is connected with the cathode gas diffusion layer. The CCM in the membrane electrode packaging structure is located on one side of the single frame and fixed on the surface of the single frame, that is, there is a gap between the CCM and the cathode diffusion layer, and the gap is consistent with the thickness of the single frame.

[0024] The CCM is composed of a hydrophilic catalyst layer and a modified perfluorosulfonic acid proton exchange membrane, that is, the hydrophilic catalyst slurry is transferred to both sides of the modified perfluorosulfonic acid proton exchange membrane to form the CCM.

[0025] The modified perfluorosulfonic acid proton exchange membrane is a silicon dioxide modified perfluorosulfonic acid proton exchange membrane, and the preparation method of the silicon dioxide modified perfluorosulfonic acid proton exchange membrane comprises: a1, tetraethoxysilane is added to anhydrous ether to form a 60g / L solution; a2, spray hydrochloric acid solution on the surface of the perfluorosulfonic acid proton exchange membrane to form a liquid film, and stand for 2h, and dry to obtain an activated perfluorosulfonic acid proton exchange membrane, the pH of the hydrochloric acid solution is 5, and the spraying amount is 6mL / cm 2a3, after the activation of the perfluorosulfonic acid proton exchange membrane is immersed into the dissolving solution and is left for 2 hours, and after removal, drying is performed, to obtain an initial modified perfluorosulfonic acid proton exchange membrane, the immersion temperature is 5℃, and the drying temperature is 50℃; a4, the initial modified perfluorosulfonic acid proton exchange membrane is left for 2 hours in a humid atmosphere, and then is subjected to constant temperature heat treatment, to obtain a nano-silicon dioxide modified perfluorosulfonic acid proton exchange membrane, the humid atmosphere is a mixed atmosphere of nitrogen and water vapor, and the volume ratio of water vapor is 5%, the standing temperature is 40℃, the constant temperature heat treatment temperature is 100℃, and the time is 4 hours. The main component of the perfluorosulfonic acid proton exchange membrane is a copolymer of tetrafluoroethylene monomer and perfluorovinyl ether monomer with sulfonic acid groups.

[0026] The hydrophilic catalyst slurry is prepared by weighing the hydrophilic catalyst, the perfluorosulfonic acid resin solution and the dispersant in a mass ratio of 1:1:0.1, and dispersing to obtain a slurry with uniform components, the hydrophilic catalyst is a platinum-carbon catalyst with a hydroxyl-modified carbon material as a carrier, the platinum element accounts for 6% of the platinum-carbon catalyst, the dispersant is isopropyl alcohol, and the mass concentration of the perfluorosulfonic acid resin is 6%.

[0027] The platinum content in the CCM is 0.4 mg / cm 2 .

[0028] The packaging method comprises the following steps:

[0029] Step 1, a CCM is prepared by using a proton exchange membrane, an anode catalyst layer and a cathode catalyst layer; a single-layer frame is pressed by using a mold; a cathode gas diffusion layer and an anode gas diffusion layer are cut out;

[0030] Step 2, an adhesive or a sticky tape is coated on the edge of a through hole in the center of the top surface of the single-layer frame, and then the CCM is bonded to the frame;

[0031] Step 3, an adhesive or a sticky tape is coated on the edge of the CCM on the frame, and the adhesive or the sticky tape covers the edge of the CCM; the adhesive is a thermoplastic material or a thermosetting material, the thermoplastic material is one of polyethylene, polypropylene and aromatic polyamide, and the thermosetting material is epoxy resin or silicone resin;

[0032] Step 4, an adhesive or a sticky tape is coated on the edge of the cathode gas diffusion layer and the anode gas diffusion layer; and then the anode gas diffusion layer, the CCM, the frame and the cathode gas diffusion layer are hot-pressed in sequence, to obtain a single-frame electrode structure. The hot-pressing temperature is 120℃, the pressure is 0.1 MPa, and the time is 0.1 min.

[0033] Example 2

[0034] A single-frame membrane electrode structure, the CCM is located on the single-frame upper surface, and the CCM upper surface is connected with the anode gas diffusion layer, and the single-frame lower surface is connected with the cathode gas diffusion layer. The CCM in the membrane electrode packaging structure is located on one side of the single-frame and is fixed on the surface of the single-frame, that is, there is a gap between the CCM and the cathode diffusion layer, and the gap is consistent with the thickness of the single-frame.

[0035] The CCM is composed of a hydrophilic catalyst layer and a modified perfluorosulfonic acid proton exchange membrane, that is, the hydrophilic catalyst slurry is transferred to both sides of the modified perfluorosulfonic acid proton exchange membrane to form the CCM.

[0036] The modified perfluorosulfonic acid proton exchange membrane adopts a silicon dioxide modified perfluorosulfonic acid proton exchange membrane, and the preparation method of the silicon dioxide modified perfluorosulfonic acid proton exchange membrane comprises: a1, tetraethoxysilane is added to anhydrous ether to form a 60g / L solution; a2, spray hydrochloric acid solution on the surface of the perfluorosulfonic acid proton exchange membrane to form a liquid film, and stand for 2h, and dry to obtain an activated perfluorosulfonic acid proton exchange membrane, the pH of the hydrochloric acid solution is 5, and the spraying amount is 6mL / cm 2 a3, immerse the activated perfluorosulfonic acid proton exchange membrane into the solution, and stand for 2h, and dry after removing to obtain a preliminary modified perfluorosulfonic acid proton exchange membrane, the immersion temperature is 5℃, and the drying temperature is 50℃; a4, stand the preliminary modified perfluorosulfonic acid proton exchange membrane in a humid atmosphere for 2h, and then heat treat at constant temperature to obtain a nano-silicon dioxide modified perfluorosulfonic acid proton exchange membrane, the humid atmosphere is a mixed atmosphere of nitrogen and water vapor, and the volume fraction of water vapor is 5%, the standing temperature is 40℃, the heat treatment temperature is 100℃, and the time is 4h. The main component of the perfluorosulfonic acid proton exchange membrane is a copolymer of tetrafluoroethylene monomer and perfluorovinyl ether monomer with sulfonic acid group.

[0037] The hydrophilic catalyst slurry is prepared by weighing the hydrophilic catalyst, perfluorosulfonic acid resin solution and dispersant in a mass ratio of 1:1:0.1, and dispersing to form a slurry with uniform components, the hydrophilic catalyst is platinum-carbon catalyst with hydroxyl modified carbon material as carrier, the platinum element content of the platinum-carbon catalyst is 6%, the dispersant is isopropyl alcohol, and the mass concentration of the perfluorosulfonic acid resin is 6%.

[0038] The platinum content in the CCM is 0.4mg / cm 2 .

[0039] The packaging method comprises:

[0040] Step 1, prepare CCM using proton exchange membrane, anode catalyst layer and cathode catalyst layer; press a single-layer frame using a mold; cut out the cathode gas diffusion layer and the anode gas diffusion layer;

[0041] Step 2, applying adhesive or adhesive tape on the edge of the center through hole of the single-layer frame top surface, and then bonding the CCM on the surface frame;

[0042] Step 3, applying adhesive or adhesive tape on the edge of the CCM on the surface frame, and the adhesive or adhesive tape covers the edge of the CCM; the adhesive uses thermoplastic material or thermosetting material, the thermoplastic material uses one of polyethylene, polypropylene and aromatic polyamide, and the thermosetting material uses epoxy resin or silicone resin;

[0043] Step 4, applying adhesive or adhesive tape on the edge of the cathode gas diffusion layer and the anode gas diffusion layer; and then hot-pressing the anode gas diffusion layer, the CCM, the frame and the cathode gas diffusion layer in sequence to obtain a single-frame electrode structure; the hot-pressing temperature is 150°C, the pressure is 2MPa, and the time is 5min.

[0044] Example 3

[0045] A single-frame membrane electrode structure, the CCM is located on the upper surface of the single frame, and the upper surface of the CCM is connected with the anode gas diffusion layer, and the lower surface of the single frame is connected with the cathode gas diffusion layer. The CCM in the membrane electrode packaging structure is located on one side of the single frame and is fixed on the surface of the single frame, that is, there is a gap between the CCM and the cathode diffusion layer, and the gap is consistent with the thickness of the single frame.

[0046] The CCM is composed of a hydrophilic catalyst layer and a modified perfluorosulfonic acid proton exchange membrane, that is, the hydrophilic catalyst slurry is transferred to both sides of the modified perfluorosulfonic acid proton exchange membrane to form the CCM.

[0047] The modified perfluorosulfonic acid proton exchange membrane uses a silica-modified perfluorosulfonic acid proton exchange membrane, and the preparation method of the silica-modified perfluorosulfonic acid proton exchange membrane comprises: a1, adding tetraethoxysilane into anhydrous ether to form a 60g / L solution; a2, spraying a hydrochloric acid solution on the surface of the perfluorosulfonic acid proton exchange membrane to form a liquid film, and standing for 2h, and drying to obtain an activated perfluorosulfonic acid proton exchange membrane, the pH of the hydrochloric acid solution is 5, and the spraying amount is 6mL / cm 2a3, the activated perfluorosulfonic acid proton exchange membrane is immersed into a dissolving solution and left for 2 hours, and after removal, drying is performed to obtain an initially modified perfluorosulfonic acid proton exchange membrane, the immersion temperature is 5℃, and the drying temperature is 50℃; a4, the initially modified perfluorosulfonic acid proton exchange membrane is left for 2 hours in a humid atmosphere, and then constant temperature heat treatment is performed to obtain a nano-silicon dioxide modified perfluorosulfonic acid proton exchange membrane, the humid atmosphere is a mixed atmosphere of nitrogen and water vapor, and the volume fraction of water vapor is 5%, the standing temperature is 40℃, the constant temperature heat treatment temperature is 100℃, and the time is 4 hours. The main component of the perfluorosulfonic acid proton exchange membrane is a copolymer of tetrafluoroethylene monomer and perfluorovinyl ether monomer with sulfonic acid groups.

[0048] The hydrophilic catalyst slurry is prepared by weighing the hydrophilic catalyst, the perfluorosulfonic acid resin solution and the dispersant in a mass ratio of 1:1:0.1, and dispersing to obtain a slurry with uniform components, the hydrophilic catalyst is a platinum-carbon catalyst with a hydroxyl-modified carbon material as a carrier, the platinum element content of the platinum-carbon catalyst is 6%, the dispersant is isopropyl alcohol, and the mass concentration of the perfluorosulfonic acid resin is 6%.

[0049] The platinum content in the CCM is 0.4 mg / cm 2 .

[0050] The packaging method comprises:

[0051] Step 1, using a proton exchange membrane, an anode catalyst layer and a cathode catalyst layer to prepare a CCM; using a mold to press a single-layer frame; cutting out a cathode gas diffusion layer and an anode gas diffusion layer;

[0052] Step 2, coating an adhesive or pasting a tape on the edge of the through hole in the center of the top surface of the single-layer frame, and then bonding the CCM to the frame;

[0053] Step 3, coating an adhesive or pasting a tape on the edge of the CCM on the frame, and the adhesive or the tape covers the edge of the CCM; the adhesive is a thermoplastic material or a thermosetting material, the thermoplastic material is one of polyethylene, polypropylene and aromatic polyamide, and the thermosetting material is epoxy resin or silicone resin;

[0054] Step 4, coating an adhesive or pasting a tape on the edge of the cathode gas diffusion layer and the anode gas diffusion layer; and then hot-pressing in the order of the anode gas diffusion layer, the CCM, the frame and the cathode gas diffusion layer to obtain a single-frame electrode structure. The hot-pressing temperature is 130℃, the pressure is 1 MPa, and the time is 2 minutes.

[0055] The membrane electrode package structure of Examples 1-3 is taken as a test example, and a conventional seven-in-one membrane electrode is taken as a comparative example. The specific packaging method is as follows: first, the proton exchange membrane is sprayed with anode catalyst layer and cathode catalyst layer on both sides to prepare a CCM; then the CCM is sealed by the adhesive cathode frame and anode frame; finally, the anode gas diffusion layer and the cathode gas diffusion layer are bonded to the frame to form a membrane electrode.

[0056] The power density of the membrane electrode of the comparative example of Examples 1-3 is basically the same under the same voltage and current density, and the power density of the membrane electrode of Examples 1-3 is slightly better than that of the comparative example, and the power density is slightly increased by about 2%. At the same time, the production efficiency of Examples 1-3 is increased by more than 8%, and the qualified rate is higher.

[0057] It can be understood that the above specific description of the present application is only used to illustrate the present application and is not limited to the technical solutions described in the embodiments of the present application. Those skilled in the art should understand that the present application can still be modified or replaced equivalently to achieve the same technical effect; as long as it meets the use needs, it is within the protection scope of the present application.

Claims

1. A packaging method for a single-sided frame film electrode structure, characterized in that: The method includes: Step 1: Prepare CCM using a proton exchange membrane, an anode catalyst layer, and a cathode catalyst layer; press out a single-layer frame using a mold; cut out the cathode gas diffusion layer and the anode gas diffusion layer; Step 2: Apply adhesive or adhesive strip to the edge of the center through hole on the top surface of the single-layer frame, and then attach the CCM to the frame; Step 3: Apply adhesive or adhesive strips to the CCM edge on the frame, ensuring that the adhesive or adhesive strips cover the CCM edge; Step 4: Apply adhesive or adhesive strips to the edges of both the cathode gas diffusion layer and the anode gas diffusion layer; then heat-press them together in the order of anode gas diffusion layer, CCM, frame and cathode gas diffusion layer to obtain a single-frame electrode structure. The encapsulation structure includes: a CCM located on the upper surface of a single frame, with an anode gas diffusion layer connected to the upper surface of the CCM and a cathode gas diffusion layer connected to the lower surface of the single frame; a gap exists between the CCM and the cathode diffusion layer, and the gap is consistent with the thickness of the single frame; the CCM is composed of a hydrophilic catalyst layer and a modified perfluorosulfonic acid proton exchange membrane, that is, the hydrophilic catalyst slurry is transferred to both sides of the modified perfluorosulfonic acid proton exchange membrane to form the CCM; The modified perfluorosulfonic acid proton exchange membrane is a silica-modified perfluorosulfonic acid proton exchange membrane. The hot pressing temperature is 120-150℃, the pressure is 0.1-2MPa, and the time is 0.1-5min.

2. The packaging method for the single-sided frame film electrode structure according to claim 1, characterized in that: The adhesive is made of thermoplastic or thermosetting materials.

3. The packaging method for the single-sided frame film electrode structure according to claim 2, characterized in that: The thermoplastic material is one of polyethylene, polypropylene, or aromatic polyamide.

4. The packaging method for the single-sided frame film electrode structure according to claim 2, characterized in that: The thermosetting material is made of epoxy resin or silicone resin.

5. The packaging method for a single-sided frame film electrode structure according to claim 1, characterized in that: The platinum loading in the CCM is 0.4 mg / cm³. 2 .

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