Base frame and electrochemical energy module

Abstract

Provided in the present invention is a base frame for an electrochemical energy module. The base frame is in the shape of a sheet and is clamped between two bipolar plates. The base frame is further provided with a first channel and a second channel, which penetrate the bipolar plates, wherein sealing members are integrally arranged on the base frame; the sealing members comprise a cathode-side sealing member enabling the second channel to communicate with a reaction region only on a cathode side, and an anode-side sealing member enabling the first channel to communicate with the reaction region only on an anode side; the cathode-side sealing member and the anode-side sealing member are provided with first sealing lips for being in contact with the bipolar plates; and the first sealing lips are provided with support frameworks.

Description

Basic framework and electrochemical energy module Technical Field

[0001] The present invention relates to an electrochemical energy module for new energy, mainly referring to a water electrolysis hydrogen production device (PEMWE) or a fuel cell device (PEMFC), and more specifically, to a basic framework of the electrochemical energy module. Background Art

[0002] Hydrogen production by water electrolysis (PEMWE) or fuel cell devices (PEMFC) are widely used in various fields, including automobiles, aircraft, and mobile communication antennas. Especially in the automotive field, fuel cells are considered to be an environmentally friendly alternative to traditional internal combustion engines. Fuel cells combine hydrogen and oxygen through catalysis to generate electricity, while also producing water as a by-product. Hydrogen production by water electrolysis devices, on the other hand, use the exact opposite process to produce hydrogen and oxygen through water electrolysis. Hydrogen production by water electrolysis devices and fuel cell devices usually consist of hundreds of individual energy modules connected in series.

[0003] A single energy module has a multi-layer structure that includes a bipolar plate (BPP), a base frame, a gas diffusion layer (GDL), a microporous layer (MPL), and a catalyst coating membrane (CCM) that together form a laminate. The layers are sealed together by gaskets arranged around their periphery between the interfaces of the layers. The gasket prevents gas from leaking out of the central pressurized area of ​​the energy module where the catalytic reaction occurs. When the energy module is assembled, the layers are compressed together to maximize the electrical contact between the layers, minimize the total thickness of the energy module, and increase the sealing performance of the gasket on the energy module. Taking a water electrolysis hydrogen production device as an example, water electrolyzed by the CCM produces hydrogen on the cathode side and oxygen on the anode side. In the base frame, the area above the CCM where hydrogen is produced is called the cathode side, while the area below the CCM is the anode side. In order to seal the hydrogen and oxygen in the base frame, cathode gaskets and anode gaskets are always used, which can prevent gas leakage to the outside. In addition, an internal seal, generally an O-ring or gasket, is also required to prevent gas generated from the cathode from leaking to the anode.

[0004] Patent document US 6057054 A discloses a membrane electrode assembly for an electrochemical fuel cell and a method for manufacturing the membrane electrode assembly. The membrane electrode assembly includes: a first porous electrode layer, a second porous electrode layer, and an ion exchange membrane disposed between the first and second porous electrode layers. An electrocatalyst is provided at the interface between the ion exchange membrane and the first and second porous electrode layers, the electrocatalyst defining an electrochemically active region. In addition, a fluid-impermeable integral seal is provided integrally with the membrane electrode assembly, wherein the integral seal includes a fluid-impermeable electrically insulating sealing material impregnated into the first and second porous electrode layers in its sealing region, wherein the integral seal extends laterally beyond the membrane and electrode layers, thereby encapsulating the peripheral regions of both the first and second electrodes and the ion exchange membrane.

[0005] Existing seals are typically made of rubber. However, in energy modules, the gas pressure can exceed 3 MPa or even 10 MPa. Therefore, sealing requirements are critical, and most rubber seals present a high risk of leakage. Under the continuous generation of high-pressure gas, rubber undergoes creep under prolonged compression. Ordinary rubber typically exhibits poor sealing properties after 10,000 hours or even more than 50,000 hours of compression, leading to leakage.

[0006] Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to provide an improved sealing component that can provide a better sealing effect on the basic frame of a water electrolysis hydrogen production device or a fuel cell device.

[0008] To address the above-mentioned technical problems, the present invention provides a base frame for an electrochemical energy module. The base frame has a sheet-like shape and is clamped between two bipolar plates. The base frame further comprises a first channel and a second channel extending through the bipolar plates. Seals are integrally mounted on the base frame. The seals include a cathode-side seal that connects the second channel to the reaction zone only on the cathode side, and an anode-side seal that connects the first channel to the reaction zone only on the anode side. The cathode and anode seals each have a first sealing lip for contacting the bipolar plates, each of which has a supporting frame. According to the present invention, a seal with an embedded supporting frame is designed to more effectively prevent water and hydrogen leakage. When the bipolar plates are pressed against the base frame, the cathode and anode seals deform due to pressure, and the supporting frame also deforms. The rubber protects the frame from wear, while the frame provides support within the rubber. This improves sealing effectiveness, provides better pressure compensation, and is simple to manufacture and has a longer service life.

[0009] According to a preferred embodiment of the present invention, the cathode-side seal and anode-side seal of the base frame include a channel sealing section extending along the perimeter and a reaction zone sealing section that, together with the channel sealing section, surrounds the first channel or the second channel. A first sealing lip is provided on the side of the channel sealing section and the reaction zone sealing section that is away from the first channel or the second channel. The sealing of the channel sealing section and the reaction zone sealing section can effectively ensure that the second channel is connected to the reaction zone only on the cathode side, and the first channel is connected to the reaction zone only on the anode side, and that the gas enclosed in the first and second channels does not escape. Further preferably, the channel sealing section and the reaction zone sealing section each have only one first sealing lip, thereby simplifying the sealing structure and reducing costs.

[0010] Furthermore, preferably, a second sealing lip is provided on the side of the channel sealing section and the reaction zone sealing section that is adjacent to the first channel or the second channel. The first and second sealing lips provide a double layer of security, enhancing the sealing effect. Preferably, the second sealing lip is a solid rubber sealing lip, thereby reducing the component cost of the sealing structure. Furthermore, it is conceivable that the channel sealing section and the reaction zone sealing section each have one first sealing lip and one second sealing lip, thereby improving the sealing effect at a lower component cost. It is also conceivable that the channel sealing section has two first sealing lips, or one first sealing lip and one second sealing lip, while the reaction zone sealing section has only one first sealing lip. Furthermore, it is also conceivable that the channel sealing section and the reaction zone sealing section each have multiple first sealing lips, or multiple first sealing lips and multiple second sealing lips, thereby enhancing the sealing effect. The specific configuration of the first and second sealing lips can be customized as needed and is not limited to the matching schemes listed above.

[0011] According to a preferred embodiment of the present invention, in order to further improve the sealing effect of the sealing lips, the first sealing lip and the second sealing lip can be tilted toward the high-pressure side. Due to the tilt angle, a self-sealing device toward the high-pressure side is formed after being compressed, thereby improving the sealing effect. Since the channel sealing section of the seal is mainly subjected to high gas pressure in one direction, the tilt directions of the first sealing lip and the second sealing lip can be the same; while the reaction zone sealing section of the seal is located between the gas channel and the reaction area and is therefore subjected to high gas pressure in two directions, the tilt directions of the first sealing lip and the second sealing lip of the reaction zone sealing section are opposite. The tilt angle of the sealing lip is preferably between 15° and 75°. If the tilt angle is 45°, a particularly good sealing effect can be achieved.

[0012] According to a preferred embodiment of the present invention, the support frame is made of elastic steel, which is easy to process and can reduce costs. It is also preferred that the cross-section of the support frame is a horizontal V-shape or C-shape. It is also conceivable that the support frame has an upper half embedded in the sealing lip and a lower half embedded in the seal base, and the elastic function of the upper half of the support frame and the stabilizing effect of the lower half are utilized to improve the sealing effect. It is also preferred that the seal is integrally formed with the base frame. Although the materials of the seal and the base frame are different, the seal and the base frame can be integrally formed by two-component injection molding, thereby further simplifying the manufacturing process and reducing manufacturing costs.

[0013] In addition, the technical problem of the present invention can also be solved by an electrochemical energy module, wherein the electrochemical energy module is a fuel cell device or a water electrolysis hydrogen production device, which has a basic framework with the above-mentioned features. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The preferred embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0015] FIG1 shows an exploded view of an electrochemical energy module;

[0016] FIG2 a shows a schematic diagram of the cathode side of a basic frame designed according to the present invention;

[0017] FIG2 b shows a schematic diagram of the anode side of a basic frame designed according to the present invention;

[0018] FIG3 shows a partial cross-sectional view of a base frame designed according to the present invention;

[0019] FIG4 a shows a schematic diagram of a first embodiment of a sealing member;

[0020] FIG. 4 b shows a schematic diagram of a second embodiment of a seal. DETAILED DESCRIPTION

[0021] In a preferred embodiment of the present invention, the electrochemical energy module takes a water electrolysis hydrogen production device as an example, and the fuel cell device has basically the same structural features, especially has basically the same basic frame. The energy module designed according to the present invention includes a plurality of single modules 1 arranged in a stacked manner. Each single module 1 includes a basic frame 3 and a bipolar plate 2 adjacent to each other (not shown in FIG1 , but visible in FIG3 ). FIG1 shows an exploded view of a single module 1 of an electrochemical energy module. The single module 1 has a stacked bipolar plate 2, a basic frame 3, a steel mesh 4, carbon paper 6, a catalyst coating film (CCM) 5, a seal 7, a proton exchange membrane (PEM) 9, a clamping ring 10, a titanium felt 8, and a titanium mesh 11. The steel mesh 4 and the carbon paper 6 constitute the cathode, and the side of the basic frame 3 where the steel mesh 4 and the carbon paper 6 are placed is the cathode side 31; the titanium felt 8 and the titanium mesh 11 constitute the anode, and the side of the basic frame 3 where the titanium felt 8 and the titanium mesh 11 are placed is the anode side 32. The base frame 3 is made of plastic, such as PEEK or other plastics. Metal can also be used, though it offers better manufacturing performance. However, it requires an insulating coating, which is expensive and poses safety risks. If the base frame 3 were made of a less expensive rubber material, the seal would easily deform and become unstable when the entire module is compressed, due to its greater compression set and poor creep properties. Therefore, there is a need for improved seals 7.

[0022] Figure 2a shows the cathode side 31 of the base frame 3, and Figure 2b shows the anode side 32 of the base frame 3. The base frame 3 has a first channel 33 and a second channel 34. The first channel 33 and the second channel 34 are used to channel gases. As shown in Figure 2b, the first channel 33 has a passageway connecting to the reaction zone 35 on the anode side 32; as shown in Figure 2a, the second channel 34 has a passageway connecting to the reaction zone 35 on the cathode side. When this single module 1 is used as a module for a water electrolysis hydrogen production device, the reaction zone 35 on the cathode side 31 produces hydrogen, which is channeled through the second channel 34; the reaction zone 35 on the anode side 32 produces oxygen, which is channeled through the first channel 33. Seals 7 ensure proper gas flow within the channels while preventing water and hydrogen leakage. To this end, an internal seal 71 and a cathode-side seal 72 are integrated on the cathode side 31, while an anode-side seal 73 is integrated on the anode side 32. The internal seal 71 prevents hydrogen generated at the cathode from entering the anode side.

[0023] FIG3 shows a partial cross-sectional view of a single module 1 of an energy module designed according to the present invention. This single module 1 is used as an example of a module for a water electrolysis hydrogen production device. As shown in the figure, during operation, hydrogen is produced on the cathode side 31 and oxygen is produced on the anode side 32, particularly high-pressure hydrogen. To prevent high-pressure gas from escaping into the external environment, ensure that the produced gas enters the designated channel, and prevent the rubber body from loosening after long-term use, the present invention has a unique design for the seal 7. All seals are integrated into the base frame 3, for example, by vulcanization or bonding. The sealing lips of at least some seals 7 have a supporting frame. In the embodiment shown in FIG3 , the sealing lips of all seals 7 have a supporting frame. The supporting frame is made of metal springs or elastic steel. As shown in the figure, the cross-section of the supporting frame is V-shaped, with the upper half of the supporting frame embedded in the sealing lip and the lower half embedded in the base of the seal.

[0024] Figure 4 illustrates different embodiments of the cathode-side seal 72 and the anode-side seal 73. In this embodiment, the cathode-side seal 72 and the anode-side seal 73 have identical structures, differing only in their installation locations on the cathode side 31 and the anode side 32. The top figure of Figure 4 shows a top view of the cathode-side seal 72 and the anode-side seal 73, which can be divided into a channel sealing section 701 and a reaction zone sealing section 702. The channel sealing section 701 prevents the generated high-pressure hydrogen from escaping to the external environment, while the reaction zone sealing section 702 prevents the generated high-pressure gas from entering the channel. The bottom figure of Figure 4 shows a partial cross-sectional view of the seal, with Figure 4a illustrating the first embodiment of the seal and Figure 4b illustrating the second embodiment. Both the channel sealing section 701 and the reaction zone sealing section 702 are provided with a first sealing lip 74 and a second sealing lip 75. As shown, the first sealing lip 74 is positioned further outboard, away from the first and second channels 33 and 34, while the second sealing lip 75 is positioned closer inboard, providing a double safety feature. In the first embodiment, the first sealing lip 74 has a support frame, while the second sealing lip 75 does not. This reduces manufacturing costs while ensuring no risk of gas leakage. In the second embodiment, both the first and second sealing lips 74, 75 have support frames to ensure optimal sealing. The first and second sealing lips 74, 75 are preferably tilted toward the high-pressure side, forming a certain tilt angle α, as shown, to enable self-sealing when subjected to high pressure. The value of the tilt angle α is preferably between 15° and 75°, with 45° being particularly preferred. As shown in Figures 4a and 4b, the first and second sealing lips 74, 75 of the channel sealing section 701 have the same tilt angle, while the first and second sealing lips 74, 75 of the reaction zone sealing section 702 have opposite tilt angles. This is because the channel sealing section 701 is subject to high pressure from only one direction, while the reaction zone sealing section 702 is subject to high pressure from both the left and right sides, and therefore has two sealing lips with opposite orientations.

[0025] While the above description describes possible embodiments by way of example, it should be understood that numerous variations exist, including combinations of known and readily conceivable technical features and implementations, such as the manner in which the connectors are connected and the materials that may be used. Furthermore, it should be understood that the exemplary embodiments are merely examples and are not intended to limit the scope, application, or configuration of the present invention in any way. The foregoing description is intended primarily to provide technical guidance for adapting at least one exemplary embodiment to the present invention. Various modifications, particularly those regarding the functionality and structure of the components described, may be made without departing from the scope of the claims.

[0026] Reference Signs 1 Energy module 2 Bipolar plate 3 Base frame 4 Steel mesh 5 Catalyst coating 6 Carbon paper 7 Seal 8 Titanium felt 9 Proton exchange membrane 10 Pressing ring 11 Titanium mesh 31 Cathode side 32 Anode side 33 First channel 34 Second channel 35 Reaction area 71 Inner seal 72 Cathode side seal 73 Anode side seal 74 First sealing lip 75 Second sealing lip 701 Channel sealing section 702 Reaction zone sealing section

Claims

1. A basic frame (3) for an electrochemical energy module, having a sheet-like shape and being clamped between two bipolar plates (2), the basic frame (3) further being provided with a first channel (33) and a second channel (34) penetrating through the bipolar plates (2). Wherein, A seal (7) is integrally provided on the basic frame (3), wherein the seal (7) includes a cathode-side seal (72) that enables the second channel (34) to communicate with the reaction region (35) only on the cathode side (31) and an anode-side seal (73) that enables the first channel (33) to communicate with the reaction region (35) only on the anode side (32), wherein the cathode-side seal (72) and the anode-side seal (73) have a first sealing lip (74) for contacting the bipolar plate (2), and the first sealing lip (74) has a support skeleton.

2. The basic frame (3) according to claim 1, characterized in that, The cathode-side seal (72) and the anode-side seal (73) have a channel sealing section (701) extending along the perimeter and a reaction zone sealing section (702) jointly surrounding the first channel (33) or the second channel (34) with the channel sealing section (701), and the first sealing lip (74) is arranged on a side of the channel sealing section (701) and the reaction zone sealing section (702) away from the first channel (33) or the second channel (34).

3. The basic frame (3) according to claim 2, characterized in that, Each of the channel sealing section (701) and the reaction zone sealing section (702) has only one of the first sealing lips (74).

4. The basic frame (3) according to claim 2, characterized in that, A second sealing lip (75) is provided on a side of the channel sealing section (701) and the reaction zone sealing section (702) close to the first channel (33) or the second channel (34).

5. The basic frame (3) according to claim 4, characterized in that, The second sealing lip (75) is a rubber solid sealing lip.

6. The basic frame (3) according to claim 5, characterized in that, Each of the channel sealing section (701) and the reaction zone sealing section (702) has one of the first sealing lips (74) and one of the second sealing lips (75).

7. The basic frame (3) according to claim 5, characterized in that, The channel sealing section (701) has two of the first sealing lips (74) or one of the first sealing lips (74) and one of the second sealing lips (75), and the reaction zone sealing section (702) has only one of the first sealing lips (74).

8. The basic frame (3) according to claim 5, characterized in that, The channel sealing section (701) and the reaction zone sealing section (702) each have a plurality of the first sealing lips (74), or have a plurality of the first sealing lips (74) and a plurality of the second sealing lips (75).

9. The base frame (3) according to any one of claims 4 to 8, wherein, the first sealing lip (74) and the second sealing lip (75) are inclined towards the high-pressure side.

10. The base frame (3) according to claim 9, wherein, the first sealing lip (74) and the second sealing lip (75) of the channel sealing section (701) have the same inclination direction.

11. The base frame (3) according to claim 9, wherein, the first sealing lip (74) and the second sealing lip (75) of the reaction zone sealing section (702) have opposite inclination directions.

12. The base frame (3) according to claim 9, wherein, the inclination angles of the first sealing lip (74) and the second sealing lip (75) are between 15° and 75°.

13. The base frame (3) according to claim 12, wherein, the inclination angles of the first sealing lip (74) and the second sealing lip (75) are 45°.

14. The base frame (3) according to any one of claims 1 to 8, wherein, the cross-section of the support skeleton is in a horizontally placed V shape or C shape.

15. The base frame (3) according to any one of claims 1 to 8, wherein, the support skeleton has an upper half embedded with the sealing lip and a lower half embedded with the sealing member matrix.

16. The base frame (3) according to claim 14 or 15, wherein, the support skeleton is made of elastic steel.

17. The base frame (3) according to any one of claims 1 to 8, wherein, the seal (7) is integrally formed with the base frame (3).

18. An electrochemical energy module, wherein, the electrochemical energy module is a fuel cell device or a water electrolysis hydrogen production device, and is characterized in that the electrochemical energy module has the base frame (3) according to any one of claims 1 to 17.

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