A novel membrane electrode package structure and packaging method for fuel cells

Abstract

The application relates to the technical field of fuel cells, in particular to a novel membrane electrode packaging structure and packaging method for fuel cells, which comprises an anode gas diffusion layer, a cathode gas diffusion layer and a CCM layer, further comprises a first frame with a first hollow area and a second frame with a second hollow area, the thickness of the first frame is greater than that of the second frame, the first frame and the second frame are respectively arranged on the front and back sides of the CCM layer, the anode gas diffusion layer and the cathode gas diffusion layer are separately arranged on the outer sides of the second frame and the first frame, and the anode gas diffusion layer, the cathode gas diffusion layer and the CCM layer are respectively covered on the second hollow area and the first hollow area. The parts and the finished product assembly of the application can be produced by using automatic equipment, and the production efficiency can be improved; the large frame designed by the application is thick and has only one layer, so that the generation of frame bubbles and wrinkles is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a novel membrane electrode packaging structure and packaging method for fuel cells. Background Technology

[0002] The current mainstream encapsulation method for membrane electrodes is as follows: First, an anode catalyst layer and a cathode catalyst layer are sprayed, directly coated, or transferred onto both sides of the proton exchange membrane to prepare a CCM (Chemical Molecular Membrane). Then, adhesive-coated cathode and anode frames seal the CCM. Finally, the anode and cathode gas diffusion layers are bonded to the frames to form a seven-layer membrane electrode. Although the above membrane electrode can meet the basic sealing requirements, it has the following two main drawbacks in large-scale mass production: 1. Low encapsulation efficiency; 2. The frames are prone to bubbles and wrinkles, making quality control difficult. Summary of the Invention

[0003] The purpose of this invention is to provide a novel membrane electrode packaging structure for fuel cells, which improves the packaging efficiency and quality of the membrane electrode.

[0004] The above-mentioned objective of the present invention is achieved through the following technical solution: a novel membrane electrode encapsulation structure for fuel cells, comprising an anode gas diffusion layer, a cathode gas diffusion layer and a CCM layer, further comprising a first frame having a first hollow area and a second frame having a second hollow area, wherein the thickness of the first frame is greater than the thickness of the second frame, the first frame and the second frame are respectively disposed on the front and back sides of the CCM layer, the anode gas diffusion layer and the cathode gas diffusion layer are respectively disposed on the outer sides of the second frame and the first frame, and the anode gas diffusion layer, the cathode gas diffusion layer and the CCM layer respectively cover the second hollow area and the first hollow area.

[0005] Preferably, the area of ​​the first border is larger than the area of ​​the second border.

[0006] Preferably, the area of ​​the second hollow area is greater than or equal to the area of ​​the first hollow area, and the first hollow area is located within the second hollow area.

[0007] Preferably, the front and back sides of the second frame are respectively provided with adhesive layers for bonding the anode gas diffusion layer and the CCM layer, and the first frame.

[0008] Another objective of this invention is to provide a novel membrane electrode packaging method for fuel cells, which improves the packaging efficiency and quality of the membrane electrode.

[0009] The above-mentioned objective of the present invention is achieved through the following technical solution: a novel membrane electrode assembly method for fuel cells, comprising the following steps:

[0010] Step 1: Prepare the CCM layer;

[0011] Preparation of the first frame: The first frame with the first hollow area is pressed out by a mold;

[0012] Preparation of the second frame: The second frame with the second hollow area is pressed out by a mold, and an adhesive layer is set on the second frame;

[0013] Cut out the cathode gas diffusion layer and the anode gas diffusion layer, and apply adhesive to the edges of the cathode gas diffusion layer and the anode gas diffusion layer;

[0014] Step 2: Heat press the first frame, CCM layer and second frame together;

[0015] Step 3: Adhere the cathode gas diffusion layer to the outer side of the first frame and the anode gas diffusion layer to the outer side of the second frame.

[0016] Preferably, in step one, an anode catalyst layer and a cathode catalyst layer are sprayed onto both sides of the proton exchange membrane to prepare a CCM layer.

[0017] Preferably, the first frame is made of materials such as PEN, PI or ETFE.

[0018] Preferably, the second frame is made of materials such as PEN, PI or ETFE, and the adhesive layer is applied by dispensing.

[0019] Preferably, in step two, the hot-pressing temperature is 30-160℃, the pressure is 0.5-4MPa, and the time is 0.5-10min.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. All parts and finished product assembly of this invention can be produced using automated equipment, which can improve production efficiency;

[0022] 2. The large border designed in this invention is thick and has only one layer, which greatly reduces the generation of bubbles and wrinkles in the border. Attached Figure Description

[0023] Figure 1 This is an exploded view of the membrane electrode structure in Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of the membrane electrode packaging in Embodiment 1 of the present invention;

[0025] Figure 3 This is a schematic diagram of the membrane electrode packaging in Embodiment 2 of the present invention;

[0026] Figure 4This is a schematic diagram of the membrane electrode packaging in Embodiment 3 of the present invention;

[0027] Figure 5 This is a schematic diagram of the membrane electrode packaging in Embodiment 4 of the present invention;

[0028] Figure 6 This is a schematic diagram of the hot pressing device in an embodiment of the present invention;

[0029] In the figure: 1-Cathode gas diffusion layer, 2-First frame, 201-First hollow area, 3-CCM layer, 4-Second frame, 401-Second hollow area, 402-Limiting protrusion, 5-Anode gas diffusion layer, 6-Hot pressing device, 601-Upper hot pressing plate, 602-Lower hot pressing plate, 603-Clamping plate, 604-Spring, 605-Negative pressure positioning component, 606-Modible positioning chuck, 607-Double-sided release paper, 608-Negative pressure hole. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings.

[0031] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0032] Example 1: As Figure 1 and Figure 2 As shown, a novel membrane electrode assembly structure for fuel cells includes an anode gas diffusion layer 5, a cathode gas diffusion layer 1, a CCM layer 3, a first frame 2, and a second frame 4. The first frame 2 and the second frame 4 are respectively disposed on the front and back sides of the CCM layer 3. The cathode gas diffusion layer 1 is disposed on the outer side of the first frame 2, and the anode gas diffusion layer 5 is disposed on the outer side of the second frame 4.

[0033] The first frame 2, the CCM layer 3, and the second frame 4 are joined together by hot pressing. The cathode gas diffusion layer 1 is bonded to the first frame 2 with adhesive, and the anode gas diffusion layer 5 is bonded to the first frame 2 with adhesive. Adhesive layers for bonding the anode gas diffusion layer 5 and the CCM layer 3 are respectively provided on the front and back sides of the second frame 4.

[0034] Both the first border 2 and the second border 4 are rectangular frames or other required shapes. The first border 2 has a first cutout area 201, and the second border 4 has a second cutout area 401. Both the first cutout area 201 and the second cutout area 401 are rectangular cutouts or other required shapes. The area of ​​the first border 2 is greater than or equal to the area of ​​the second border 4, meaning the external dimensions (length and width) of the first border 2 are greater than the external dimensions of the second border 4, and the thickness of the first border 2 is greater than the thickness of the second border 4.

[0035] The area of ​​the second hollow area 401 is greater than or equal to the area of ​​the first hollow area 201, that is, the dimensions (length and width) of the second hollow area 401 are greater than the dimensions of the first hollow area 201. In the projection direction, the first hollow area 201 is located within the second hollow area 401. The outer dimensions of the CCM layer 3 are smaller than the outer dimensions of the second frame 4, but larger than the dimensions of the second hollow area 401. The outer dimensions of the anode gas diffusion layer 5 are larger than the outer dimensions of the second frame 4.

[0036] After encapsulation, the anode gas diffusion layer 5, the cathode gas diffusion layer 1, and the CCM layer 3 cover the first cutout area 201 and the second cutout area 401, respectively. That is, the cathode gas diffusion layer 1 and the CCM layer 3 cover the first cutout area 201 on both sides, and the anode gas diffusion layer 5 and the CCM layer 3 cover the second cutout area 401 on both sides.

[0037] Example 2: As Figure 3 As shown, the difference from Example 1 is that the large frame 2 and the small frame 4 seal the CCM3 together, the adhesive layer of the small frame 4 is bonded to the large frame 2, and the gas diffusion layer 5 is bonded to the small frame 4 with adhesive.

[0038] Example 3: As Figure 4 As shown, the difference from Example 1 is that the large frame 2 and the small frame 4 seal the CCM3 together, the adhesive layer of the small frame 4 is bonded to the large frame 2, and the gas diffusion layer 5 is bonded to the large frame 2 by an adhesive.

[0039] Example 4: Figure 5 As shown, the difference from Embodiment 1 is that the second frame 4 is provided with a limiting protrusion 402 for abutting against the side of the CCM layer 3. The limiting protrusion 402 is located on the outside of the second hollow area 401. The height of the limiting protrusion 402 is less than the thickness of the CCM layer 3. The limiting protrusion 402 is used to prevent the CCM layer 3 from shifting during the hot pressing process among the first frame 2, the CCM layer 3, and the second frame 4.

[0040] Example 5: The difference from Example 1 is that the second frame 4, CCM3 and the first frame 2 are bonded together by dispensing.

[0041] A novel membrane electrode assembly (MEA) encapsulation method for fuel cells includes the following steps:

[0042] Step 1: Prepare CCM layer 3 by spraying, directly coating or transferring the anode catalyst layer and cathode catalyst layer on both sides of the proton exchange membrane to prepare CCM layer 3.

[0043] Preparation of the first frame 2: The first frame 2 with the first hollow area 201 is pressed out by a mold;

[0044] Preparation of the second frame 4: The second frame 4 with the second hollow area 401 is pressed out by a mold, and an adhesive layer is set on the second frame 4;

[0045] Cut out the cathode gas diffusion layer and the anode gas diffusion layer, and apply adhesive to the edges of the cathode gas diffusion layer and the anode gas diffusion layer;

[0046] The above steps are not in any particular order.

[0047] Step 2: The first frame 2, CCM layer 3 and the second frame 4 are hot-pressed together by a hot-pressing device 6. The hot-pressing temperature is 30-160℃, the pressure is 0.5-4MPa, and the time is 0.5-10min.

[0048] Step 3: Adhere the cathode gas diffusion layer to the outer side of the first frame 2, and adhere the anode gas diffusion layer to the outer side of the second frame 4.

[0049] like Figure 6 As shown, the hot pressing device 6 in step two includes an upper hot pressing plate 601 and a lower hot pressing plate 602. The upper hot pressing plate 601 is driven by a hydraulic cylinder to move up and down relative to the lower hot pressing plate 602. Both the upper hot pressing plate 601 and the lower hot pressing plate 602 are equipped with heating wires for heating.

[0050] The lower hot press plate 602 is provided with clamping plates 603 for positioning the first frame 2. The clamping plates 603 are distributed around the first frame 2. The lower end of the clamping plate 603 is hinged to the lower hot press plate 602 and swings towards the opposite clamping plate 603 by a spring 604. The upper end of the clamping plate 603 is provided with a guide surface that is inclined outward.

[0051] A movable positioning clamp 606 for positioning the CCM layer 3 is provided above the lower hot press plate 602. The movable positioning clamp 606 is distributed around the CCM layer 3 and is moved by a cylinder or electric push rod. A negative pressure positioning component 605 is also provided on the lower hot press plate 602. The negative pressure positioning component 605 includes a negative pressure suction cup, which is connected to a negative pressure pump through a pipe and is located in the first hollow area 201 of the first frame 2. After the movable positioning clamp 606 positions the CCM layer 3, the negative pressure suction cup adheres to the CCM layer 3 to prevent displacement. Then, the movable positioning clamp 606 moves outward, leaving the space between the upper hot press plate 601 and the lower hot press plate 602.

[0052] Double-sided release paper 607 is laid on the surface of the upper hot press plate 601. Multiple negative pressure holes 608 are evenly distributed on the upper hot press plate 601. These negative pressure holes 608 use negative pressure to adhere the double-sided release paper 607 to the lower surface of the upper hot press plate 601. Because the second frame 4 is thin and lightweight, it is prone to deformation during clamping and positioning. Therefore, adhering the second frame 4 to the double-sided release paper 607 prevents it from falling off. During hot pressing, the double-sided release paper 607 separates the second frame 4 from the upper hot press plate 601, preventing the second frame 4 from sticking to the upper hot press plate 601. After hot pressing, the negative pressure holes 608 are inflated, separating the double-sided release paper 607 from the upper hot press plate 601 for the next step. In subsequent steps, the double-sided release paper 607 can be easily peeled off the surface of the second frame 4.

Claims

1. A membrane electrode assembly structure for a fuel cell, comprising an anode gas diffusion layer (5), a cathode gas diffusion layer (1), and a CCM layer (3), characterized in that: It also includes a first frame (2) with a first cutout area (201) and a second frame (4) with a second cutout area (401). The thickness of the first frame (2) is greater than the thickness of the second frame (4). The first frame (2) and the second frame (4) are respectively disposed on the front and back sides of the CCM layer (3). The anode gas diffusion layer (5) and the cathode gas diffusion layer (1) are respectively disposed on the outer sides of the second frame (4) and the first frame (2). The anode gas diffusion layer (5), the cathode gas diffusion layer (1) and the CCM layer (3) respectively cover the second cutout area (401) and the first cutout area (201). (2) The area of ​​the second frame (4) is greater than the area of ​​the second cutout area (401), the area of ​​the second cutout area (401) is greater than the area of ​​the first cutout area (201), and the projection of the first cutout area (201) is located within the second cutout area (401); the second frame (4) is provided with a limiting protrusion (402) for abutting against the side of the CCM layer (3), the limiting protrusion (402) is located outside the second cutout area (401), the height of the limiting protrusion (402) is less than the thickness of the CCM layer (3), and the limiting protrusion (402) is used to prevent the CCM layer (3) from shifting during the hot pressing process of the first frame (2), the CCM layer (3) and the second frame (4); This encapsulation structure is prepared through the following steps: Step 1, prepare the CCM layer (3); prepare the first frame (2): press out the first frame (2) with the first hollow area (201) by a mold; Preparation of the second frame (4): The second frame (4) with the second hollow area (401) is pressed out by a mold, and an adhesive layer is set on the second frame (4); Cut out the cathode gas diffusion layer and the anode gas diffusion layer, and apply adhesive to the edges of the cathode gas diffusion layer and the anode gas diffusion layer; Step 2: Press the first border (2), CCM layer (3), and second border (4) together using heat; Step 3: Adhere the cathode gas diffusion layer (1) to the outer side of the first frame (2) and adhere the anode gas diffusion layer (5) to the outer side of the second frame (4).

2. The membrane electrode assembly structure for a fuel cell according to claim 1, characterized in that: The front and back sides of the second frame (4) are respectively provided with adhesive layers for bonding the anode gas diffusion layer (5) and the CCM layer (3) and the first frame (2).

3. The membrane electrode assembly structure for a fuel cell according to claim 1, characterized in that: In step one, the anode catalyst layer and the cathode catalyst layer are sprayed, directly coated or transferred onto both sides of the proton exchange membrane to prepare the CCM layer (3).

4. The membrane electrode assembly structure for a fuel cell according to claim 1, characterized in that: The first border (2) is made of PEN, PI or ETFE material.

5. The membrane electrode assembly structure for a fuel cell according to claim 1, characterized in that: The second frame (4) is made of PEN, PI or ETFE material with adhesive layers on both sides, or directly made of adhesive strips, or made by applying adhesive to PEN, PI or ETFE material.

6. The membrane electrode assembly structure for a fuel cell according to claim 1, characterized in that: In step two, the hot pressing temperature is 30-160℃, the pressure is 0.5-4MPa, and the time is 0.5-10min.

Images