A bipolar plate structure for improving the performance and life of a fuel cell

Abstract

This invention discloses a bipolar plate structure for improving the performance and lifespan of fuel cells. This bipolar plate structure combines a cathode plate and an anode plate using adhesive or welding. Both the cathode and anode plates have gas flow channels, which are optimized to ensure performance and lifespan. The bipolar plates are then assembled under pressure with membrane electrode assemblies (MEAs) in an alternating stacking manner to form a fuel cell stack. This invention relates to the field of fuel cell technology. This bipolar plate structure, by employing a bipolar plate structure where the ridges of the cathode and anode of the fuel cell bipolar plate face each other, increases the contact area, reduces contact resistance, avoids the risk of catalyst cracking, and improves the lifespan of the fuel cell stack. By narrowing the flow channels at the front and rear ends of the cathode bipolar plate, a pressure difference is created with the normal adjacent flow channels, ensuring smooth drainage of water from the flow channels and under the ridges while increasing mass transfer capacity, resulting in a significant improvement in performance and lifespan.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, specifically to a bipolar plate structure for improving fuel cell performance and lifespan. Background Technology

[0002] As a highly efficient and clean energy conversion device, fuel cells have shown broad application prospects in transportation, stationary power generation, and portable power sources. They directly convert the chemical energy of fuel into electrical energy through electrochemical reactions, offering significant advantages such as high energy conversion efficiency, low environmental pollution, and low noise, making them a crucial direction for global energy technology transformation. In recent years, with the rapid development of the hydrogen energy industry and the gradual improvement of related infrastructure, fuel cell technology has gradually moved from demonstration operation to large-scale commercial application, and has been validated by the market in scenarios such as vehicle power and distributed energy supply.

[0003] However, during the industrialization process, the long-term durability and operational reliability of fuel cells remain one of the core bottlenecks restricting their large-scale commercial application. Among these, the fuel cell stack, as the core component, directly impacts the lifespan and operational economy of the entire system due to performance degradation. Bipolar plates, as key multifunctional components of the stack, not only distribute reactant gases, conduct current, dissipate heat, and remove reaction products, but also suffer from corrosion, aging, and uneven fluid distribution during long-term operation, which are significant factors leading to battery performance degradation and shortened lifespan. Especially under harsh conditions of variable loads, start-stop cycles, and low temperatures, traditional bipolar plates still face severe challenges in terms of material stability, flow field design reliability, and interface contact consistency, making it difficult to meet the urgent demands for ultra-long lifespan and high reliability in scenarios such as vehicle power systems.

[0004] Therefore, how to significantly improve the mechanical stability and mass and heat transfer efficiency of bipolar plates under long-term operating conditions through structural design, thereby effectively delaying the overall performance degradation of fuel cells and extending their service life, has become a key focus of technological breakthroughs and patent layout in this field. Summary of the Invention

[0005] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a bipolar plate structure that improves the performance and lifespan of fuel cells. It solves the problem of small contact area and high contact resistance in currently mainstream corrugated flow channels under pressure during assembly. Furthermore, the contact surface, with its dispersed points, poses a risk of stress concentration leading to catalyst cracking. The design of this invention, while ensuring drainage and under-ridge mass transfer, reduces contact resistance and avoids catalyst cracking.

[0006] (II) Technical Solution To achieve the above objectives, the present invention is implemented through the following technical solution: a bipolar plate structure for improving the performance and lifespan of a fuel cell, wherein the cathode plate and the anode plate are joined together by adhesive or welding, and gas flow channels exist on the cathode plate and the anode plate respectively. The flow channels are optimized to ensure performance and lifespan, forming a bipolar plate, which is assembled under pressure by alternating stacking with membrane electrode assembly to form a fuel cell stack. The bipolar plate structure includes an anode inlet, a cathode inlet, an anode front-end distribution area, a cathode front-end distribution area, a cathode flow channel front-end narrowing area, a reaction zone, a cathode flow channel rear-end narrowing area, a cathode rear-end distribution area, an anode rear-end distribution area, a cathode outlet, and an anode outlet.

[0007] Preferably, the front narrowing region of the cathode flow channel, the reaction region, and the rear narrowing region of the cathode flow channel constitute the total reaction region.

[0008] Preferably, the cathode flow channel front end narrowing region narrows the flow channel every other flow channel to ensure the pressure difference between adjacent flow channels, and the design of the cathode flow channel rear end narrowing region is consistent with the cathode flow channel front end narrowing region.

[0009] Preferably, while ensuring that both the anode and cathode of the bipolar plate structure of the fuel cell stack are DC channels, the anode and cathode are made to have the same period, so that the ridge of the cathode of the bipolar plate is opposite to the ridge of the anode. This design can reduce the contact resistance and make the catalyst of the membrane electrode uniformly stressed, so that the catalyst will not crack due to stress concentration, thereby ensuring its life.

[0010] Preferably, in order to ensure mass transfer and drainage under the ridge, the flow channels are narrowed at the front and rear ends of the reaction zone on the cathode side. This design can create a pressure difference between adjacent flow channels, thereby allowing gas to flow under the ridge and driving the drainage of water under the ridge, thus improving the performance of the fuel cell.

[0011] Preferably, the flow channel distribution area formed by the anode front-end distribution area, cathode front-end distribution area, cathode rear-end distribution area and anode rear-end distribution area is replaced with a dot matrix distribution area.

[0012] (III) Beneficial Effects This invention provides a bipolar plate structure for improving the performance and lifespan of fuel cells. Compared with existing technologies, it has the following advantages: (1) The bipolar plate structure that improves the performance and life of fuel cells increases the contact area and reduces the contact resistance by making the ridges of the cathode and anode of the fuel cell face each other, thus avoiding the risk of catalyst cracking and improving the life of the fuel cell stack.

[0013] (2) The bipolar plate structure that improves the performance and life of fuel cells has narrowed the flow channels at the front and rear ends of the cathode, which can generate a pressure difference with the normal adjacent flow channels. This ensures that the water in the flow channels and under the ridge can be discharged smoothly while increasing the mass transfer capacity, which has a significant effect on improving performance and life.

[0014] (3.) The bipolar plate structure that improves the performance and lifespan of fuel cells can reduce processing costs and processing difficulty by using direct current channels for both the cathode and anode. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the fluid flow region of the present invention; Figure 2 This is a schematic diagram of the narrowing region at the front end of the anode flow channel in this invention; Figure 3 This is a schematic diagram of the structure of the cathode plate and anode plate of the present invention; In the figure, 1 is the anode inlet; 2 is the cathode inlet; 3 is the anode front distribution area; 4 is the cathode front distribution area; 5 is the cathode flow channel front narrowing area; 6 is the reaction zone; 7 is the cathode flow channel rear narrowing area; 8 is the cathode rear distribution area; 9 is the anode rear distribution area; 10 is the cathode outlet; 11 is the anode outlet; 12 is the anode plate; and 13 is the cathode plate. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Please see Figure 1-3 The present invention provides three technical solutions: a bipolar plate structure for improving fuel cell performance and lifespan, specifically including the following embodiments: Example 1: A bipolar plate structure for improving the performance and lifespan of a fuel cell. The bipolar plate structure combines the cathode plate 13 and the anode plate 12 by adhesive or welding. Gas flow channels exist on the cathode plate 13 and the anode plate 12 respectively. The flow channels are optimized to ensure performance and lifespan, forming a bipolar plate. The bipolar plate is assembled under pressure by alternating stacking with the membrane electrode assembly to form a fuel cell stack. The bipolar plate structure includes an anode inlet 1, a cathode inlet 2, an anode front-end distribution area 3, a cathode front-end distribution area 4, a cathode flow channel front-end narrowing area 5, a reaction area 6, a cathode flow channel rear-end narrowing area 7, a cathode rear-end distribution area 8, an anode rear-end distribution area 9, a cathode outlet 10, and an anode outlet 11.

[0018] In this embodiment of the invention, the front narrowing region 5 of the cathode flow channel, the reaction region 6, and the rear narrowing region 7 of the cathode flow channel constitute the total reaction region.

[0019] In this embodiment of the invention, the front narrowing region 5 of the cathode flow channel narrows the flow channel every other flow channel to ensure the pressure difference between adjacent flow channels, and the design of the rear narrowing region 7 of the cathode flow channel is consistent with that of the front narrowing region 5 of the cathode flow channel.

[0020] Example 2: A bipolar plate structure for improving the performance and lifespan of a fuel cell. The bipolar plate structure combines the cathode plate 13 and the anode plate 12 by means of adhesive or welding. Gas flow channels exist on the cathode plate 13 and the anode plate 12 respectively. The flow channels are optimized to ensure performance and lifespan, forming a bipolar plate. The bipolar plate is assembled under pressure by alternating stacking with the membrane electrode to form a fuel cell stack. The bipolar plate structure includes an anode inlet 1, a cathode inlet 2, an anode front-end distribution area 3, a cathode front-end distribution area 4, a cathode flow channel front-end narrowing area 5, a reaction area 6, a cathode flow channel rear-end narrowing area 7, a cathode rear-end distribution area 8, an anode rear-end distribution area 9, a cathode outlet 10, and an anode outlet 11.

[0021] In this embodiment of the invention, the front narrowing region 5 of the cathode flow channel, the reaction region 6, and the rear narrowing region 7 of the cathode flow channel constitute the total reaction region.

[0022] In this embodiment of the invention, the front narrowing region 5 of the cathode flow channel narrows the flow channel every other flow channel to ensure the pressure difference between adjacent flow channels, and the design of the rear narrowing region 7 of the cathode flow channel is consistent with that of the front narrowing region 5 of the cathode flow channel.

[0023] In this embodiment of the invention, while ensuring that both the anode and cathode of the bipolar plate structure of the fuel cell stack are direct current channels, the anode and cathode are periodically aligned, so that the ridge of the cathode of the bipolar plate is opposite to the ridge of the anode. This design can reduce contact resistance and make the catalyst of the membrane electrode uniformly pressurized, preventing catalyst cracking due to stress concentration, thereby ensuring lifespan. In order to ensure mass transfer and drainage under the ridge, the flow channels are narrowed at the front and rear ends of the reaction zone on the cathode side. This design can create a pressure difference between adjacent flow channels, thereby allowing gas to flow under the ridge and driving the drainage of water under the ridge, thereby improving the performance of the fuel cell.

[0024] Example 3: The technical solution of this embodiment of the invention differs from that of Example 2 in that the flow channel distribution area formed by the anode front distribution area 3, the cathode front distribution area 4, the cathode rear distribution area 8 and the anode rear distribution area 9 is replaced with a dot matrix distribution area.

[0025] In summary, this invention employs a bipolar plate structure, aligning the ridges of the fuel cell cathode and anode, thereby increasing the contact area, reducing contact resistance, avoiding the risk of catalyst cracking, and improving the lifespan of the fuel cell stack. By narrowing the flow channels at the front and rear ends of the cathode, a pressure difference can be generated with the normal adjacent flow channels, ensuring smooth drainage of water from the flow channels and under the ridges while increasing mass transfer capacity, resulting in significant improvements in performance and lifespan. Furthermore, since both the cathode and anode are direct-flow channels, processing costs and processing difficulty can be reduced.

[0026] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0027] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A bipolar plate structure for improving the performance and lifespan of a fuel cell, characterized in that: The bipolar plate structure combines the cathode plate (13) and the anode plate (12) by means of adhesive or welding. There are gas flow channels on the cathode plate (13) and the anode plate (12). The flow channels are optimized to ensure performance and lifespan, forming a bipolar plate. It is assembled under pressure by alternating stacking with the membrane electrode to form a fuel cell stack. The bipolar plate structure includes an anode inlet (1), a cathode inlet (2), an anode front-end distribution area (3), a cathode front-end distribution area (4), a cathode flow channel front-end narrowing area (5), a reaction area (6), a cathode flow channel rear-end narrowing area (7), a cathode rear-end distribution area (8), an anode rear-end distribution area (9), a cathode outlet (10), and an anode outlet (11).

2. The bipolar plate structure for improving fuel cell performance and lifespan according to claim 1, characterized in that: The cathode flow channel front narrowing area (5), reaction area (6), and cathode flow channel rear narrowing area (7) constitute the total reaction area.

3. The bipolar plate structure for improving fuel cell performance and lifespan according to claim 1, characterized in that: The cathode flow channel front narrowing region (5) narrows the flow channel every other flow channel to ensure the pressure difference between adjacent flow channels, and the design of the cathode flow channel rear narrowing region (7) is consistent with the cathode flow channel front narrowing region (5).

4. The bipolar plate structure for improving fuel cell performance and lifespan according to claim 1, characterized in that: While ensuring that both the anode and cathode of the fuel cell stack bipolar plate structure are DC channels, the anode and cathode are made to have the same period, so that the ridge of the cathode of the bipolar plate is opposite to the ridge of the anode.

5. A bipolar plate structure for improving fuel cell performance and lifespan according to claim 4, characterized in that: To ensure mass transfer and drainage under the ridge, the flow channels were narrowed at the front and rear ends of the reaction zone on the cathode side.

6. The bipolar plate structure for improving fuel cell performance and lifespan according to claim 1, characterized in that: The flow channel distribution area formed by the anode front distribution area (3), cathode front distribution area (4), cathode rear distribution area (8) and anode rear distribution area (9) is replaced with a dot matrix distribution area.

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