Packaging method and packaging structure for single-frame membrane electrode

Abstract

The present invention relates to the field of membrane electrodes. Disclosed are a packaging method and packaging structure for a single-frame membrane electrode. A frame base material is separately connected to a first sealing member and a second sealing member to form a first assembly; the first assembly is connected to a first gas diffusion layer to form a second assembly; a catalyst coating CCM is connected to a second gas diffusion layer to form a third assembly; and the second assembly and the third assembly are assembled and aligned by means of a mold, and hot-pressed to form a single-frame membrane electrode having a sealing member. The present invention has the beneficial effects: a sealing element for stack assembly and a membrane electrode are assembled together in advance, so that the subsequent fuel cell stack assembly process is greatly simplified, the assembly precision is high, and the sealing element and a frame have good adhesion and are not easy to move, avoiding rework caused by misalignment of the sealing element during stack assembly, improving the stack assembly efficiency and yield, and reducing the costs.

Description

Packaging method and structure of single-frame membrane electrode TECHNICAL FIELD

[0001] The present application relates to the field of membrane electrode, in particular to a packaging method and structure of single-frame membrane electrode. BACKGROUND

[0002] At present, fuel cell stack sealing process can be divided into laminated sealing process and overall adhesive packaging process. The laminated sealing process generally uses silicone as a sealing material, which is formed on the bipolar plate by dispensing or injection molding. After the stack is stacked, the sealing material is compressed by assembly pressure to achieve the sealing of the gas field of the stack. The advantage of this method is that the stack can be easily disassembled, and the running state of the battery plate or membrane electrode can be easily checked and analyzed, which is convenient for optimizing the design scheme. The disadvantage is that the adhesion between the sealing strip and the bipolar plate is poor, and the adhesion between the two is poor, which is prone to misalignment and other problems. During the curing process, impurities in the bipolar plate, especially graphite bipolar plate, are easily introduced into the adhesive strip, forming a defect point. Therefore, this process has higher requirements for equipment (such as high-precision visual positioning, dispensing or injection molding equipment, additional curing process), and the investment in production line equipment is often high. In addition, the overall adhesive packaging process uses special adhesive and stack structure design to integrally bond the battery plate and MEA to achieve permanent sealing (not disassembled) of the gas field, which has the advantages of high production efficiency, reliable sealing effect, flexible production process, and low investment cost of equipment production line. However, the adhesive material has higher requirements. SUMMARY

[0003] The purpose of the present application is to provide a packaging method and structure of single-frame membrane electrode to simplify the assembly process, improve the assembly precision, and improve the assembly efficiency.

[0004] The purpose of the present application is achieved by the following technical solutions:

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

[0006] S1: connecting the first face and the second face of the frame substrate with the first seal and the second seal respectively to form a first combination, the first face and the second face being large planes opposite to each other of the frame substrate;

[0007] S2: connecting one side of the first combination with a first gas diffusion layer to form a second combination, wherein the first gas diffusion layer is connected to the first face of the frame substrate;

[0008] S3: coating a cathode catalyst layer and an anode catalyst layer on both sides of a proton exchange membrane to obtain a three-layer structure of catalyst coating CCM after drying;

[0009] S4: connecting the catalyst coating layer CCM with a second gas diffusion layer to form a third assembly;

[0010] S5: assembling the second assembly and the third assembly in position through a mold and hot-pressing through a servo press to form a single-frame membrane electrode with a sealant, wherein the catalyst coating layer CCM is connected to the second face of the frame substrate.

[0011] In some embodiments of the present application, in step S1, the frame substrate is coated with a primer in the bonding area of the first sealant, the frame substrate is coated with a primer in the bonding area of the second sealant, the first sealant is directly injected to the first face through a glue injection machine, the second sealant is directly injected to the second face through a glue injection machine, and the frame substrate, the first sealant and the second sealant are integrally cured and formed.

[0012] In some embodiments of the present application, the curing temperature of the frame substrate, the first sealant and the second sealant is 100-150°C, and the curing time is 1-10 min.

[0013] In some embodiments of the present application, the curing temperature of the frame substrate, the first sealant and the second sealant is 110°C, and the curing time is 3 min.

[0014] In some embodiments of the present application, in step S2, the first assembly and the first gas diffusion layer are bonded through an adhesive.

[0015] In some embodiments of the present application, in step S4, the catalyst coating layer CCM and the second gas diffusion layer are bonded through an adhesive.

[0016] In some embodiments of the present application, the first assembly and the first gas diffusion layer are bonded through cold pressing, and the catalyst coating layer CCM and the second gas diffusion layer are bonded through cold pressing.

[0017] In some embodiments of the present application, in step S5, the hot-pressing temperature is 100-150°C, the hot-pressing pressure is 1-5T, and the hot-pressing time is 10-60 s.

[0018] In some embodiments of the present application, the hot-pressing temperature is 130°C, the hot-pressing pressure is 3T, and the hot-pressing time is 30 s.

[0019] An encapsulation structure of a single-frame membrane electrode made by the encapsulation method as described above, characterized in that it comprises a frame base material, a first sealing member, a second sealing member, a first gas diffusion layer, a catalyst coating layer CCM and a second gas diffusion layer, the first sealing member and the second sealing member are respectively arranged on the first face and the second face of the frame base material, the first gas diffusion layer is connected to the first face of the frame base material, the catalyst coating layer CCM is connected to the second face of the frame base material, and the second gas diffusion layer is connected to the side of the catalyst coating layer CCM away from the first gas diffusion layer, wherein the first sealing member and the second sealing member are located on the outside of the frame base material, and the first gas diffusion layer, the catalyst coating layer CCM and the second gas diffusion layer are located on the inside of the frame base material.

[0020] The encapsulation method and encapsulation structure of a single-frame membrane electrode of the present application assemble the sealing member for stack assembly together with the membrane electrode in advance, greatly simplifying the assembly process of the rear-end fuel cell stack, and having high assembly precision, good adhesion of the sealing member to the frame, and low movement, avoiding the rework caused by misalignment of the sealing member during stack assembly, improving the stack assembly efficiency and yield, reducing the cost, and finally obtaining a single-frame membrane electrode and sealing member integrated encapsulation structure, which has good sealing performance, simple structure and reliable use. BRIEF DESCRIPTION OF DRAWINGS

[0021] Fig. 1 is a top view of the encapsulation structure of a single-frame membrane electrode of the present application;

[0022] Fig. 2 is a sectional view of the encapsulation structure of a single-frame membrane electrode of the present application;

[0023] Fig. 3 is a structural schematic diagram of a first combination of the present application;

[0024] Fig. 4 is a structural schematic diagram of a second combination of the present application;

[0025] Fig. 5 is a structural schematic diagram of a third combination of the present application.

[0026] In the drawings, 1 is a frame base material; 11 is a first face; 12 is a second face; 2 is a first sealing member; 3 is a second sealing member; 4 is a first gas diffusion layer; 5 is a catalyst coating layer CCM; 6 is a second gas diffusion layer; 100 is a first combination; 200 is a second combination; and 300 is a third combination. DETAILED DESCRIPTION

[0027] The specific embodiments of the present application are described in further detail below in conjunction with the drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0028] In the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer" and the like used in the present application indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the connection or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0030] As shown in FIGS. 1-5, the first aspect of the embodiments of the present application proposes a packaging method of a single-frame membrane electrode, comprising the following steps:

[0031] S1: connecting the first face 11 and the second face 12 of the frame substrate 1 with the first sealing member 2 and the second sealing member 3 respectively to form a first combination 100, wherein the first face 11 and the second face 12 are opposite large planes of the frame substrate 1;

[0032] S2: connecting one side of the first combination 100 with the first gas diffusion layer 4 to form a second combination 200, wherein the first gas diffusion layer 4 is connected to the first face 11 of the frame substrate 1;

[0033] S3: coating the proton exchange membrane on both sides with a cathode catalyst layer and an anode catalyst layer, and drying to obtain a three-layer structure of the catalyst coating CCM 5;

[0034] S4: connecting the catalyst coating CCM 5 with the second gas diffusion layer 6 to form a third combination 300;

[0035] S5: assembling the second combination 200 and the third combination 300 in position through a mold, and hot pressing through a servo press to form a single-frame membrane electrode with a sealing member, wherein the catalyst coating CCM 5 is connected to the second face 12 of the frame substrate 1.

[0036] Based on the above technical scheme, the packaging method of the single-frame membrane electrode of the application assembles the sealing element used for assembling the stack together with the membrane electrode in advance, greatly simplifies the assembly process of the rear-end fuel cell stack, has high assembly precision, good adhesion between the sealing element and the frame, and is not easy to move, avoids the rework caused by misalignment of the sealing element during the stack assembly process, improves the stack assembly efficiency and yield, reduces the cost, and finally obtains the integrated packaging structure of the single-frame membrane electrode and the sealing element. It should be noted that CCM is the abbreviation of catalyst coated membrane, which is the place where the electrochemical reaction of the fuel cell occurs, and is the fuel cell chip.

[0037] In some embodiments of the application, as shown in Figures 2-4, in step S1, the bonding area of the frame substrate 1 and the first sealing element 2 is coated with a primer, the bonding area of the frame substrate 1 and the second sealing element 3 is coated with a primer, the first sealing element 2 is directly injected to the first surface 11 by a glue injection machine, the second sealing element 3 is directly injected to the second surface 12 by a glue injection machine, and the frame substrate 1, the first sealing element 2 and the second sealing element 3 are integrally cured and formed. Compared with the conventional single-sealing rubber strip of the stack, the application has the first sealing element 2 and the second sealing element 3, and two sealing rubber strips are further designed between the frame substrate 1 and the sealing element. When one of the sealing rubber strips is abnormal or fails, the other sealing rubber strip can still play a sealing role, which greatly improves the sealing reliability and durability of the stack, and the integrally cured and formed mode after injection by the glue injection machine also makes the forming effect better and the sealing effect more stable.

[0038] Specifically, the curing temperature of the frame substrate 1, the first sealing element 2 and the second sealing element 3 is 100-150℃, and the curing time is 1-10min. Setting the curing conditions in the above range can effectively improve the curing effect and make the forming effect and sealing effect better.

[0039] More specifically, the curing temperature of the frame substrate 1, the first sealing element 2 and the second sealing element 3 is 110℃, and the curing time is 3min. The curing temperature and time are 110℃ and 3min respectively, which can further achieve the purpose of improving the forming effect and sealing effect.

[0040] In some embodiments of the application, as shown in Figure 4, in step S2, the first combination 100 and the first gas diffusion layer 4 are bonded by an adhesive. The adhesive can simply and conveniently connect the first combination 100 and the first gas diffusion layer 4 together to realize reliable connection of the two.

[0041] Specifically, as shown in FIG. 5, in step S4, the catalyst coating layer CCM5 is attached to the second gas diffusion layer 6 by an adhesive. Similarly, the adhesive can simply and conveniently connect the catalyst coating layer CCM5 and the second gas diffusion layer 6 together, achieving reliable connection of the two.

[0042] More specifically, as shown in FIG. 4 and FIG. 5, the first assembly 100 is attached to the first gas diffusion layer 4 by cold pressing, and the catalyst coating layer CCM5 is attached to the second gas diffusion layer 6 by cold pressing. The single-frame membrane electrode anode and cathode gas diffusion layers can be firmly attached to the catalyst coating layer CCM5 or the frame by short-term cold pressing, thereby improving production efficiency. Moreover, because the process of hot pressing is reduced, the catalyst coating layer CCM5 is less affected by expansion and contraction caused by temperature changes, and the phenomenon of bulging and warping of the membrane electrode product is reduced, and the appearance of the product is more flat.

[0043] In some embodiments of the present application, in step S5, the hot pressing temperature is 100-150℃, the hot pressing pressure is 1T-5T, and the hot pressing time is 10-60s. The temperature, pressure, and time of the above hot pressing are all in a suitable value range, and the assembly connected together can be efficiently and reliably installed.

[0044] Specifically, the hot pressing temperature is 130℃, the hot pressing pressure is 3T, and the hot pressing time is 30s. Using more accurate temperature, pressure, and time can further improve the effect of hot pressing and improve the assembly efficiency.

[0045] As shown in FIG. 1-FIG. 5, the second aspect of the embodiments of the present application proposes a packaging structure of a single-frame membrane electrode made by the above-mentioned packaging method, which includes a frame substrate 1, a first sealing member 2, a second sealing member 3, a first gas diffusion layer 4, a catalyst coating layer CCM5, and a second gas diffusion layer 6. The first sealing member 2 and the second sealing member 3 are respectively arranged on the first face 11 and the second face 12 of the frame substrate 1, the first gas diffusion layer 4 is connected to the first face 11 of the frame substrate 1, the catalyst coating layer CCM5 is connected to the second face 12 of the frame substrate 1, and the second gas diffusion layer 6 is connected to the side of the catalyst coating layer CCM5 away from the first gas diffusion layer 4. The first sealing member 2 and the second sealing member 3 are located on the outside of the frame substrate 1, and the first gas diffusion layer 4, the catalyst coating layer CCM5, and the second gas diffusion layer 6 are located on the inside of the frame substrate 1. Using the above packaging method, an integrated packaging structure of a single-frame membrane electrode and a sealing member can be obtained, which has good sealing performance, a simple structure, and reliable use.

[0046] In summary, the packaging method and structure of the single-frame membrane electrode of the application assembles the sealing element for the assembly of the stack together with the membrane electrode in advance, greatly simplifies the assembly process of the rear-end fuel cell stack, has high assembly precision, good adhesion between the sealing element and the frame, is not easy to move, avoids the rework caused by misalignment of the sealing element during the assembly of the stack, improves the assembly efficiency and yield of the stack, reduces the cost, and finally obtains the integrated packaging structure of the single-frame membrane electrode and the sealing element, which has good sealing performance, simple structure and reliable use.

[0047] The above is only the preferred embodiment of the application. It should be noted that those skilled in the art can make several improvements and replacements without departing from the technical principles of the application. These improvements and replacements should also be considered as the protection scope of the application.

Claims

1. A method of packaging a single-sided frame-free membrane electrode, characterized by, The method comprises the following steps: S1: connecting a first face and a second face of a frame base respectively with a first seal and a second seal to form a first combination, the first face and the second face being opposite large faces of the frame base; S2: connecting one side of the first combination with a first gas diffusion layer to form a second combination, wherein the first gas diffusion layer is connected to the first face of the frame base; S3: coating a cathode catalyst layer and an anode catalyst layer on both sides of a proton exchange membrane to obtain a three-layer catalyst coating CCM after drying; S4: connecting the catalyst coating CCM with a second gas diffusion layer to form a third combination; S5: assembling the second combination and the third combination in position through a mold and hot-pressing with a servo press to form a single-frame membrane electrode with seals, wherein the catalyst coating CCM is connected to the second face of the frame base.

2. The method of packaging a single-sided frame-free film electrode according to claim 1, wherein In step S1, the bonding area of the frame base and the first seal is coated with a primer, the bonding area of the frame base and the second seal is coated with a primer, the first seal is directly injected to the first face by an injection machine, the second seal is directly injected to the second face by an injection machine, and the frame base, the first seal and the second seal are integrally cured and formed.

3. The method of packaging a single-sided frame-free film electrode according to claim 2, wherein The curing temperature of the frame base, the first seal and the second seal is 100-150°C, and the curing time is 1-10 min.

4. The method of packaging a single-sided frame-free membrane electrode according to claim 3, wherein The curing temperature of the frame base, the first seal and the second seal is 110°C, and the curing time is 3 min.

5. The method of packaging a unibond membrane electrode according to claim 1, wherein In step S2, the first combination and the first gas diffusion layer are bonded by an adhesive.

6. The method of packaging a single-sided frame-free membrane electrode according to claim 5, wherein In step S4, the catalyst coating CCM and the second gas diffusion layer are bonded by an adhesive.

7. The method of packaging a single-sided frame-free membrane electrode according to claim 6, wherein The first combination and the first gas diffusion layer are bonded by cold pressing, and the catalyst coating CCM and the second gas diffusion layer are bonded by cold pressing.

8. The method of packaging a unibond membrane electrode according to claim 1, wherein In step S5, the hot-pressing temperature is 100-150°C, the hot-pressing pressure is 1-5T, and the hot-pressing time is 10-60 s.

9. The method of packaging a single-sided frame-free membrane electrode according to claim 8, wherein, The hot-pressing temperature is 130°C, the hot-pressing pressure is 3T, and the hot-pressing time is 30 s.

10. A packaging structure of a single-sided frame membrane electrode fabricated by the packaging method according to any one of claims 1 to 9, characterized by The method comprises a frame base, a first seal, a second seal, a first gas diffusion layer, a catalyst coating CCM and a second gas diffusion layer, the first seal and the second seal are arranged on a first face and a second face of the frame base, the first gas diffusion layer is connected to the first face of the frame base, the catalyst coating CCM is connected to the second face of the frame base, and the second gas diffusion layer is connected to a side of the catalyst coating CCM away from the first gas diffusion layer, wherein the first seal and the second seal are located on the outside of the frame base, and the first gas diffusion layer, the catalyst coating CCM and the second gas diffusion layer are located on the inside of the frame base.

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