Membrane electrode structure of fuel cell

Abstract

The utility model relates to the technical field of fuel cells, and discloses a fuel cell membrane electrode structure which comprises a proton exchange membrane, hydrophilic coatings are fixedly connected to the upper side and the lower side of the outer wall of the proton exchange membrane, and an anode catalyst layer is fixedly connected to the top of the hydrophilic coating on the upper side. The bottom of the hydrophilic coating on the lower side is fixedly connected with a cathode catalyst layer, the inner walls of the anode catalyst layer and the cathode catalyst layer are fixedly connected with nanofiber conductive networks, and the top of the anode catalyst layer is provided with a corrugated anode gas diffusion layer. According to the utility model, through the design of multi-layer alternate stacking, the contact area of reaction is greatly increased, so that fuel and an oxidizing agent can be more fully contacted with the catalytic layer, the catalytic efficiency is obviously improved, and the introduction of the nanofiber conductive network effectively improves electron conduction, reduces resistance and improves the catalytic efficiency. Therefore, the electron transmission is smoother, the reaction uniformity is improved, and the service life of the battery is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to fuel cell technical field especially relates to fuel cell membrane electrode structure. BACKGROUND

[0002] Fuel cell is a kind of energy conversion device that chemical energy in fuel is converted into electric energy by the form of oxidation-reduction reaction, and hydrogen fuel cell is the fuel cell that can use hydrogen as fuel, and the chemical energy of hydrogen is converted into electric energy by electrochemical reaction, and the electrochemical reaction product is water, and the whole reaction process does not bring pollution to the environment, and membrane electrode is the key core component of fuel cell power generation.

[0003] Traditional membrane electrode is mainly composed of proton exchange membrane, anode catalytic layer, cathode catalytic layer, anode gas diffusion layer and cathode gas diffusion layer, but hydrogen is unevenly distributed on the surface of membrane electrode after long time use, which leads to uneven reaction and reduces battery performance, and the prior art ensures that reaction gas is evenly distributed on the surface of the whole membrane electrode by increasing flow field plate outside diffusion layer, avoids local gas concentration too high or too low, thereby improves the uniformity and stability of reaction, and optimizes battery performance, but in actual use process, due to long time use, catalytic efficiency is reduced, so that the battery cannot completely catalyze hydrogen, reduces the performance and stability of the battery, and affects the service life of the battery. UTILITY MODEL CONTENTS

[0004] In order to make up for the above shortcomings, the utility model provides fuel cell membrane electrode structure, aims at improving the problem of the prior art that long time use leads to reduced catalytic efficiency, so that the battery cannot completely catalyze hydrogen, reduces the performance and stability of the battery, and affects the service life of the battery.

[0005] In order to realize the above-mentioned purpose, the utility model adopts the following technical scheme: fuel cell membrane electrode structure, including proton exchange membrane, the outer wall of the proton exchange membrane is fixedly connected with hydrophilic coating on the upside and downside, the top of the hydrophilic coating on the upside is fixedly connected with anode catalytic layer, the bottom of the hydrophilic coating on the downside is fixedly connected with cathode catalytic layer, the inner wall of the anode catalytic layer and the cathode catalytic layer is fixedly connected with nanofiber conductive network, the top of the anode catalytic layer is provided with corrugated anode gas diffusion layer, the bottom of the cathode catalytic layer is provided with grid-shaped cathode gas diffusion layer, the top of the corrugated anode gas diffusion layer is fixedly connected with anode flow field plate, the bottom of the grid-shaped cathode gas diffusion layer is fixedly connected with cathode flow field plate, the side away from each other of the cathode flow field plate and the anode flow field plate is fixedly connected with protective layer, the outer wall of the proton exchange membrane is provided with fixing mechanism on the left side and the right side, and the fixing mechanism is used to fix each component.

[0006] As a further description of the above technical solution:

[0007] The fixing mechanism comprises a plurality of protrusions, the plurality of protrusions are fixedly connected to the outer walls of the left and right sides of the anode catalytic layer and the cathode catalytic layer, the outer wall top of the proton exchange membrane is provided with an upper frame on the left and right sides, the outer wall bottom of the proton exchange membrane is provided with a lower frame on the left and right sides, the distal ends of the two protective layers are fixedly connected with a plurality of positioning blocks on the left and right sides, a plurality of positioning grooves are formed in the interiors of the upper frame and the lower frame, the plurality of positioning blocks are respectively engaged with the corresponding positioning grooves, a plurality of reserved holes are formed in the outer walls of the front and back sides of the upper frame and the lower frame, the inner walls of the upper plurality of reserved holes are threadedly connected with screws, and the plurality of screws are respectively threadedly connected with the corresponding lower reserved holes.

[0008] As a further description of the above technical solution:

[0009] The inner walls of the cathode flow field plate and the anode flow field plate are provided with a plurality of drainage channels, and the distances between the plurality of drainage channels are equal.

[0010] As a further description of the above technical solution:

[0011] The sizes of the cathode catalytic layer and the anode catalytic layer are equal, and the sizes of the anode flow field plate and the cathode flow field plate are equal.

[0012] As a further description of the above technical solution:

[0013] The distal ends of the two hydrophilic coatings are fixedly connected with fixing glue on the front and back sides, the anode catalytic layer is fixedly connected with the upper hydrophilic coating through the upper fixing glue, and the cathode catalytic layer is fixedly connected with the lower hydrophilic coating through the lower fixing glue.

[0014] As a further description of the above technical solution:

[0015] The outer walls of the two upper frames and the two lower frames are fixedly connected with an insulating layer, and the plurality of screws all penetrate through the corresponding insulating layer.

[0016] As a further description of the above technical solution:

[0017] The inner walls of the lower plurality of reserved holes are fixedly connected with a threaded sleeve, and the plurality of screws are threadedly connected with the corresponding threaded sleeves.

[0018] As a further description of the above technical solution:

[0019] Cross grooves are formed in the top portions of the plurality of screws, and the outer surfaces of the plurality of screws are subjected to smooth treatment.

[0020] This utility model has the following beneficial effects:

[0021] 1. In this invention, the multi-layered alternating stacking design significantly increases the contact area of ​​the reaction, allowing the fuel and oxidant to more fully contact the catalyst layer, thereby significantly improving catalytic efficiency. The introduction of the nanofiber conductive network effectively improves electron conduction, reduces resistance, and makes electron transport smoother. The corrugated anode gas diffusion layer and the mesh-like cathode gas diffusion layer optimize gas distribution, avoiding local gas accumulation or insufficiency, improving reaction uniformity, and thus improving battery performance and stability, and extending battery life.

[0022] 2. In this utility model, the initial positioning and alignment are achieved by the bonding of the protrusions with the proton exchange membrane, laying the foundation for subsequent precise assembly. The engagement of the protective layer positioning block with the frame positioning groove ensures accurate alignment and initial fixation of the components, improving assembly efficiency. The screw connection between the upper and lower frames tightly fixes each component, greatly enhancing the stability of the structure. When the fuel cell is working, it can effectively prevent the displacement or loosening of each component, maintain a stable structure, ensure good performance, and thus extend the battery life. Attached Figure Description

[0023] Figure 1 This is a perspective view of the fuel cell membrane electrode structure proposed in this utility model;

[0024] Figure 2 This is a partial structural exploded view of the fuel cell membrane electrode structure proposed in this utility model;

[0025] Figure 3 for Figure 2 Enlarged view of point A;

[0026] Figure 4 This is a partial structural schematic diagram of the fuel cell membrane electrode structure proposed in this utility model;

[0027] Figure 5 This is a schematic diagram of the fixing mechanism of the fuel cell membrane electrode structure proposed in this utility model.

[0028] Legend:

[0029] 1. Proton exchange membrane; 2. Fixing mechanism; 201. Protrusion; 202. Upper frame; 203. Lower frame; 204. Positioning block; 205. Positioning groove; 206. Reserved hole; 207. Screw; 3. Hydrophilic coating; 4. Anode catalyst layer; 5. Cathode catalyst layer; 6. Nanofiber conductive network; 7. Corrugated anode gas diffusion layer; 8. Mesh cathode gas diffusion layer; 9. Anode flow field plate; 10. Cathode flow field plate; 11. Protective layer; 12. Drainage channel; 13. Fixing adhesive; 14. Insulating layer; 15. Threaded sleeve; 16. Cross groove. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] Reference Figure 1 , Figure 2 and Figure 4This utility model provides an embodiment of a fuel cell membrane electrode structure, including a proton exchange membrane 1, which conducts protons to ensure smooth proton transfer between the anode and cathode. Hydrophilic coatings 3 are fixedly connected to both the upper and lower sides of the membrane's outer wall to promote proton transfer and improve reaction efficiency. An anode catalyst layer 4 is fixedly connected to the top of the upper hydrophilic coating 3 to accelerate the anode oxidation reaction, and a cathode catalyst layer 5 is fixedly connected to the bottom of the lower hydrophilic coating 3 to promote the cathode reduction reaction. Nanofiber conductive networks 6 are fixedly connected to the inner walls of both the anode catalyst layer 4 and the cathode catalyst layer 5 to enhance electron conduction and reduce resistance. A corrugated anode gas diffusion layer 7 is provided at the top of the anode catalyst layer 4 to facilitate uniform diffusion of the anode gas and improve reaction uniformity. A mesh-like cathode gas diffusion layer 8 is provided at the bottom of the cathode catalyst layer 5 to promote uniform distribution of the cathode gas and optimize reaction performance. The top of the corrugated anode gas diffusion layer 7... An anode flow field plate 9 is fixedly connected to the anode flow field plate 9, which guides the flow and distribution of the anode reaction gas. A cathode flow field plate 10 is fixedly connected to the bottom of the mesh-like cathode gas diffusion layer 8, which regulates the flow of the cathode reaction gas. A protective layer 11 is fixedly connected to the side of the cathode flow field plate 10 and the anode flow field plate 9 that is far away from each other, which protects the cathode flow field plate 10 and the anode flow field plate 9. Fixing mechanisms 2 are provided on the left and right sides of the outer wall of the proton exchange membrane 1, which are used to fix the components and ensure the stability of the structure. Multiple drainage channels 12 are opened on the inner walls of the cathode flow field plate 10 and the anode flow field plate 9. The distance between the multiple drainage channels 12 is equal. The drainage channels 12 can drain the water generated by the reaction in time, avoiding water accumulation that affects the reaction. The cathode catalyst layer 5 and the anode catalyst layer 4 are the same size, and the anode flow field plate 9 and the cathode flow field plate 10 are the same size, which ensures the uniformity and symmetry of the reaction on both sides and helps to improve the overall performance and stability of the battery.

[0032] Specifically, during fuel cell operation, fuel enters the corrugated anode gas diffusion layer 7 through the anode flow field plate 9 and diffuses uniformly to the anode catalyst layer 4. Under the action of the nanofiber conductive network 6 and the catalyst, an oxidation reaction occurs, producing protons and electrons. Protons are transferred to the cathode via the hydrophilic coating 3 and the proton exchange membrane 1, while electrons travel to the cathode via the external circuit. The oxidant enters the mesh-like cathode gas diffusion layer 8 through the cathode flow field plate 10 and then to the cathode catalyst layer 5, where it undergoes a reduction reaction with protons and electrons. The hydrophilic coating 3 promotes proton transfer, and the nanofiber conductive network 6 enhances electron conduction. The corrugated anode gas diffusion layer 7 and the grid-like cathode gas diffusion layer 8 optimize gas distribution, improve reaction uniformity and efficiency, the fixing mechanism 2 ensures the stability of the position of each component, the protective layer 11 protects the anode flow field plate 9 and the cathode flow field plate 10, the drainage channel 12 can drain the water generated by the reaction in time, and avoid water accumulation affecting the reaction. The cathode catalyst layer 5 and the anode catalyst layer 4 are the same size, and the anode flow field plate 9 and the cathode flow field plate 10 are the same size, which ensures the uniformity and symmetry of the reaction on both sides, and helps to improve the overall performance and stability of the battery.

[0033] Reference Figure 1 and Figure 5 The fixing mechanism 2 includes multiple protrusions 201, which are fixedly connected to the left and right sides of the outer wall of the anode catalyst layer 4 and the cathode catalyst layer 5. The protrusions 201 are used for initial positioning and fixing of the upper frame 202 and the lower frame 203. The upper frame 202 is provided on the top left and right sides of the outer wall of the proton exchange membrane 1, which can provide fixation and support for the top. The lower frame 203 is provided on the bottom left and right sides of the outer wall of the proton exchange membrane 1, which serves to fix and support the bottom. Multiple positioning blocks 204 are fixedly connected to the left and right sides of the two protective layers 11 at their farthest ends. The positioning blocks 204 help to accurately align the components. Multiple positioning grooves 205 are opened inside the upper frame 202 and the lower frame 203. The multiple positioning blocks 204 are respectively engaged with the corresponding positioning grooves 205. The assembly method achieves initial fixation and precise alignment. The outer walls of the upper frame 202 and lower frame 203 are provided with pre-drilled holes 206 on both the front and rear sides. These holes 206 are used to install screws 207. The inner walls of the upper pre-drilled holes 206 are threaded with screws 207, and each screw 207 is threaded into its corresponding lower pre-drilled hole 206. The connection of the screws 207 ensures the frame is tightly fixed, guaranteeing structural stability. Insulation layers 14 are fixedly connected to the outer walls of both upper frames 202 and both lower frames 203 to prevent current leakage and improve safety. Multiple screws 207 penetrate the corresponding insulation layers 14. Threaded sleeves 15 are fixedly connected to the inner walls of the lower pre-drilled holes 206, and each screw 207 is threaded into its corresponding threaded sleeve 15. The threaded sleeves 15 enhance the stability of the screw 207 connection.

[0034] Specifically, firstly, the protrusions 201 on the left and right sides of the anode catalyst layer 4 and the cathode catalyst layer 5 are attached to the left and right sides of the proton exchange membrane 1 for initial positioning and alignment. Then, the upper frame 202 and the lower frame 203 are placed on the top and bottom of the proton exchange membrane 1, respectively. At this time, the positioning block 204 on the protective layer 11 engages with the positioning groove 205 inside the upper frame 202 and the lower frame 203, achieving initial fixation and accurate alignment between the components. Next, screws 207 are screwed into the reserved hole 206 of the upper frame 202 and then into the corresponding reserved hole 206 of the lower frame 203. Through the connection of the screws 207, the upper frame 202 and the lower frame 203 are tightly fixed together, thereby securing all parts of the entire membrane electrode structure. The components are firmly fixed in place to ensure that no components will shift or loosen during fuel cell operation, maintaining a stable structure and good performance. The insulating layer 14 blocks the path of current conduction through the frame to the outside, preventing current from being accidentally conducted from the inside of the membrane electrode structure to the upper frame 202 and lower frame 203, and then to other parts where there should be no electrical conduction, thereby ensuring that the current flows within the predetermined path, improving the stability and safety of battery operation. When the screw 207 is screwed into the upper reserved hole 206, it will engage with the threaded sleeve 15 in the lower reserved hole 206. The threaded sleeve 15 provides a more precise and firm threaded fit, which can withstand greater tightening force, making the connection between the screw 207 and the lower frame 203 tighter and more reliable.

[0035] Reference Figure 1 , Figure 3 and Figure 4 The fixing adhesive 13 enhances the bond strength between the hydrophilic coating 3 and the anode catalyst layer 4 and the cathode catalyst layer 5. The anode catalyst layer 4 is fixedly connected to the upper hydrophilic coating 3 through the upper fixing adhesive 13, ensuring the stability of the anode catalyst layer 4. The cathode catalyst layer 5 is fixedly connected to the lower hydrophilic coating 3 through the lower fixing adhesive 13, ensuring the stability of the cathode catalyst layer 5. The top of each of the multiple screws 207 is provided with a cross groove 16, which facilitates the installation and removal of the screws 207. The outer surface of each of the multiple screws 207 is smoothed, which reduces the resistance during installation, reduces wear, and improves service life.

[0036] Specifically, the fixing adhesive 13 effectively prevents the anode catalyst layer 4 and the cathode catalyst layer 5 from relative displacement or detachment from the hydrophilic coating 3 due to forces generated by internal reactions, vibrations, and external factors, thereby ensuring the stability and reliability of the membrane electrode structure and enabling the fuel cell to continuously and efficiently carry out electrochemical reactions. The cross groove 16 facilitates tightening and loosening operations using tools such as screwdrivers. The smooth treatment of the outer surface of the screw 207 reduces the friction between it and other components during installation, allowing the screw 207 to pass through the reserved hole 206 and the threaded sleeve 15 more smoothly, avoiding installation difficulties or component wear caused by excessive friction.

[0037] Working principle: Before using the device, during fuel cell operation, fuel enters the corrugated anode gas diffusion layer 7 through the anode flow field plate 9 and diffuses evenly to the anode catalyst layer 4. Under the action of the nanofiber conductive network 6 and the catalyst, an oxidation reaction occurs to produce protons and electrons. Protons are transferred to the cathode through the hydrophilic coating 3 and the proton exchange membrane 1, while electrons are transferred to the cathode through the external circuit. The oxidant enters the mesh-like cathode gas diffusion layer 8 through the cathode flow field plate 10 and then to the cathode catalyst layer 5, where it undergoes a reduction reaction with protons and electrons. The hydrophilic coating 3 promotes proton transfer, the nanofiber conductive network 6 enhances electron conduction, and the corrugated anode gas diffusion layer 7 and the mesh-like cathode gas diffusion layer 8 optimize gas distribution, improving reaction uniformity and efficiency.

[0038] Furthermore, by attaching the protrusions 201 on the left and right sides of the anode catalyst layer 4 and the cathode catalyst layer 5 to the left and right sides of the proton exchange membrane 1, preliminary positioning and alignment are achieved. Then, the upper frame 202 and the lower frame 203 are placed on the top and bottom of the proton exchange membrane 1, respectively. At this time, the positioning block 204 on the protective layer 11 engages with the positioning groove 205 inside the upper frame 202 and the lower frame 203, achieving preliminary fixation and accurate alignment between the components. Next, the screw 207 is screwed into the reserved hole 206 of the upper frame 202 and then screwed into the corresponding reserved hole 206 of the lower frame 203. Through the connection of the screw 207, the upper frame 202 and the lower frame 203 are tightly fixed together, thereby firmly fixing all the components of the entire membrane electrode structure, ensuring that the components will not shift or loosen during the operation of the fuel cell, and maintaining a stable structure and good performance.

[0039] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A fuel cell membrane electrode structure, comprising a proton exchange membrane (1), characterized in that: The proton exchange membrane (1) has a hydrophilic coating (3) fixedly connected to both the upper and lower sides of its outer wall. An anode catalyst layer (4) is fixedly connected to the top of the upper hydrophilic coating (3), and a cathode catalyst layer (5) is fixedly connected to the bottom of the lower hydrophilic coating (3). A nanofiber conductive network (6) is fixedly connected to the inner walls of both the anode catalyst layer (4) and the cathode catalyst layer (5). A corrugated anode gas diffusion layer (7) is provided on the top of the anode catalyst layer (4), and the cathode catalyst layer (5)... A mesh-like cathode gas diffusion layer (8) is provided at the bottom. An anode flow field plate (9) is fixedly connected to the top of the corrugated anode gas diffusion layer (7). A cathode flow field plate (10) is fixedly connected to the bottom of the mesh-like cathode gas diffusion layer (8). A protective layer (11) is fixedly connected to the side of the cathode flow field plate (10) that is far away from the anode flow field plate (9). Fixing mechanisms (2) are provided on the left and right sides of the outer wall of the proton exchange membrane (1). The fixing mechanisms (2) are used to fix each component.

2. The fuel cell membrane electrode structure according to claim 1, characterized in that: The fixing mechanism (2) includes multiple protrusions (201), which are fixedly connected to the left and right sides of the outer walls of the anode catalyst layer (4) and the cathode catalyst layer (5). The top left and right sides of the outer wall of the proton exchange membrane (1) are each provided with an upper frame (202), and the bottom left and right sides of the outer wall of the proton exchange membrane (1) are each provided with a lower frame (203). Multiple positioning blocks (204) are fixedly connected to the left and right sides of the two protective layers (11) at opposite ends. The frame (202) and the lower frame (203) are provided with multiple positioning grooves (205), and multiple positioning blocks (204) are engaged with the corresponding positioning grooves (205). The upper frame (202) and the lower frame (203) are provided with reserved holes (206) on the front and rear sides of the outer wall. The inner walls of the multiple reserved holes (206) on the upper side are threaded with screws (207), and the multiple screws (207) are threaded with the corresponding reserved holes (206) on the lower side.

3. The fuel cell membrane electrode structure according to claim 1, characterized in that: The inner walls of both the cathode flow field plate (10) and the anode flow field plate (9) are provided with multiple drainage channels (12), and the distance between the multiple drainage channels (12) is equal.

4. The fuel cell membrane electrode structure according to claim 1, characterized in that: The cathode catalyst layer (5) has the same size as the anode catalyst layer (4), and the anode flow field plate (9) has the same size as the cathode flow field plate (10).

5. The fuel cell membrane electrode structure according to claim 1, characterized in that: The two hydrophilic coatings (3) are fixedly connected to each other at their opposite ends by a fixing adhesive (13). The anode catalyst layer (4) is fixedly connected to the upper hydrophilic coating (3) by the upper fixing adhesive (13), and the cathode catalyst layer (5) is fixedly connected to the lower hydrophilic coating (3) by the lower fixing adhesive (13).

6. The fuel cell membrane electrode structure according to claim 2, characterized in that: The outer walls of the two upper frame frames (202) and the two lower frame frames (203) are all fixedly connected with an insulating layer (14), and the plurality of screws (207) penetrate the corresponding insulating layer (14).

7. The fuel cell membrane electrode structure according to claim 2, characterized in that: The inner walls of the multiple pre-drilled holes (206) on the lower side are all fixedly connected with threaded sleeves (15), and the multiple screws (207) are all threadedly connected to the corresponding threaded sleeves (15).

8. The fuel cell membrane electrode structure according to claim 2, characterized in that: Each of the screws (207) has a cross groove (16) on its top, and the outer surface of each of the screws (207) is smoothed.

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