A fuel cell cathode plate and a fuel cell

Abstract

This invention relates to a fuel cell cathode plate and a fuel cell. The fuel cell cathode plate includes a plate body and an inlet / outlet area, a reaction area, and a reactant transition area. The reactant transition area is provided with air reversal holes, an air diffusion zone, and an air buffer boss, which together realize the flow reversal of air from the direction perpendicular to the plate body to the direction parallel to the plate body, primary uniform distribution, and secondary distribution stabilization, ultimately uniformly delivering the air to the meandering air guide channel in the reaction area. This invention effectively solves the problems of water accumulation in the cathode channel and poor gas mass transfer by reducing the channel width at the lower arc of the air guide channel to accelerate airflow drainage and setting a sloping boss at the upper arc to lift the airflow and enhance mass transfer, thus significantly improving the power generation performance and plate utilization rate of the fuel cell.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell plates, specifically relating to a fuel cell cathode plate and a fuel cell. Background Technology

[0002] A proton exchange membrane fuel cell is a device that generates electricity by electrochemically reacting hydrogen and oxygen. It provides a site to ensure the orderly and stable conduct of the electrochemical reaction between hydrogen and oxygen; its structure consists of multiple bipolar plates and membrane electrode assemblies stacked in sequence to form a battery pack.

[0003] The bipolar plate is a key component of a fuel cell, primarily responsible for uniformly feeding the reactant gases into the flow field on the plate surface and promptly removing the water continuously generated during the electrochemical reaction. Therefore, a more advantageous plate structure needs to be designed to make the electrochemical reaction of hydrogen and oxygen more efficient.

[0004] However, in the existing technology, the electrode structure mostly adopts a straight flat bottom guide channel, which has poor drainage effect. The generated water tends to accumulate at the bottom of each guide channel, occupying the reaction area of ​​the membrane electrode, increasing the resistance to hydrogen ion transfer, and thus reducing the power generation efficiency of the fuel cell stack. Summary of the Invention

[0005] The purpose of this invention is to provide a fuel cell cathode plate and a fuel cell to overcome the above-mentioned technical defects.

[0006] To address the aforementioned technical problems, the present invention provides a fuel cell cathode plate, comprising a plate body, and further comprising:

[0007] The import / export area is located at the edge of the plate and has multiple common openings that penetrate the plate. The reaction zone, located in the center of the plate, is provided with a meandering air guide channel; The reactant transition zone is located on the plate between the inlet / outlet zone and the reaction zone. It is provided with an air tumbling hole, an air diffusion zone and multiple air buffer protrusions in the direction of air flow. The air-turning waist hole is used to receive air from the common port and change the air flow direction; the air diffusion zone is used for primary uniform distribution of the air; and the air buffer boss is used for secondary uniform distribution and delivery of the air to the air guide groove.

[0008] According to a fuel cell cathode plate, the plurality of said common ports include a hydrogen common port, an air common port, and a coolant common port; The air common port is positioned between the hydrogen common port and the coolant common port.

[0009] According to a fuel cell cathode plate, the air reversing perforation is adjacent to and directly connected to the air common port in the reactant transition region, for changing the flow direction of air from the air common port from a direction perpendicular to the plate plane to a direction parallel to the plate plane.

[0010] According to a fuel cell cathode plate, the air diffusion zone is a strip-shaped planar region disposed on both sides of the air inversion waist hole; The bottom surface of the air diffusion zone is lower than the bottom surface of the air guide groove, which is used to receive and distribute the air from the air reversing waist hole and guide it to the air buffer boss.

[0011] According to a fuel cell cathode plate, there are multiple air buffer protrusions, which are arranged in an array between the air diffusion area and the air guide groove. The cross-sectional shape of the air buffer boss is waist-shaped, which is used to perform secondary distribution and flow stabilization of the air after it has been distributed once by the air diffusion zone, and to uniformly deliver the air to each of the air guide slots.

[0012] According to a fuel cell cathode plate, a plurality of air buffer protrusions are evenly spaced along the width direction of the plate body, and the gap between every two adjacent air buffer protrusions uniquely corresponds to and connects to the inlet of an air guide groove.

[0013] According to a fuel cell cathode plate, the meandering air guide channel is composed of periodically spaced upper and lower arcs.

[0014] According to a fuel cell cathode plate, the width of the air guide groove at the lower arc is smaller than its width at the non-lower arc, so as to increase the airflow velocity through the lower arc.

[0015] According to a fuel cell cathode plate, a sloping boss is provided at the bottom of the groove at the upper arc; The sloping protrusion is configured to generate a lifting force on the air when it flows through it, guiding the air to generate an upward diffusion flow field toward the membrane electrode, thereby enhancing the gas mass transfer process at the hydrogen-oxygen electrochemical reaction interface.

[0016] The present invention also provides a fuel point battery having at least one fuel cell cathode plate.

[0017] The beneficial effects of this invention are as follows: (1) By setting the air common port between the hydrogen common port and the coolant common port, and combining it with the air diffusion zone set on both sides of the air reversing waist hole, the air intake path is optimized, the diffusion capacity of air to the entire reaction area is significantly enhanced, thereby improving the utilization rate of the effective reaction area of ​​the electrode plate.

[0018] (2) By setting a meandering air guide groove on the cathode plate of the fuel cell and specifically reducing the groove width at the lower arc where water is prone to accumulate, the air flow rate at this point is increased, generating a strong gas shear force. This allows the liquid water generated by the hydrogen-oxygen reaction to be discharged from the flow channel in a timely and effective manner, solving the problem of poor flow and avoiding the loss of membrane electrode reaction area and the increase of hydrogen ion transmission resistance caused by water accumulation, thus maintaining the low internal resistance and high performance of the battery.

[0019] (3) By setting an upward sloping protrusion at the bottom of the guide channel at the upper arc, the air is lifted and diffuses upward toward the membrane electrode when it flows through. This design actively disturbs the flow field, breaks the gas boundary layer on the surface of the membrane electrode, and greatly enhances the mass transfer process of the reactant gas (oxygen) to the catalyst layer of the membrane electrode, thereby strengthening the rate and efficiency of the hydrogen-oxygen electrochemical reaction.

[0020] To make the above description of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a plan view of the cathode plate of a fuel cell.

[0022] Figure 2 This is a plan view of the airflow channel.

[0023] Figure 3 This is a side view of the airflow channel.

[0024] Explanation of reference numerals in the attached figures: 10. Import / Export Area; 11. Hydrogen Common Port; 12. Air Common Port; 13. Coolant Common Port; 20. Reaction zone; 21. Air guide channel; 211. Upper arc; 2111. Sloping boss; 212. Lower arc; 30. Reactant transition zone; 31. Air overturning vent; 32. Air diffusion zone; 33. Air buffer boss. Detailed Implementation

[0025] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0026] It should be noted that, in this invention, the upper, lower, left, and right in the figure are regarded as the upper, lower, left, and right of the fuel cell cathode plate described in this specification.

[0027] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0028] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0029] This embodiment relates to a fuel cell cathode plate. Please refer to [link / reference]. Figure 1 It includes the plate body, as well as the inlet and outlet area 10, the reaction area 20, and the reactant transition area 30.

[0030] The inlet / outlet area 10 is located at the edge of the plate and contains multiple common openings that penetrate the plate. This area serves as a channel for the reaction medium (hydrogen, air, coolant) to enter and exit the battery stack, and is crucial for achieving multi-layered structure integration of the battery stack.

[0031] Multiple common ports include hydrogen common port 11, air common port 12, and coolant common port 13. For example... Figure 1 As shown, there are two sets of hydrogen common port 11, air common port 12, and coolant common port 13, and the two sets of common ports are symmetrical about the center of the fuel cell cathode plate. The positions of hydrogen common port 11, air common port 12, and coolant common port 13 on the left side are upper, middle, and lower, and their positions on the right side are lower, middle, and upper.

[0032] The air common port 12 is positioned between the hydrogen common port 11 and the coolant common port 13. Placing the air common port 12 in the middle shortens the airflow path from the common manifold to the center of the reactant transition region 30. This helps reduce airflow resistance (pressure drop), allowing the entire air distribution system to fill more quickly.

[0033] The "common manifold" is a common flow channel that runs through the entire fuel cell stack and is used to uniformly transport or collect reaction media (such as hydrogen or air) or cooling media (such as coolant).

[0034] Hydrogen and coolant are located on opposite sides of the air, and this symmetrical layout helps to create a more balanced reactant supply and heat dissipation environment across the entire plate surface. As the primary carrier of cathode reactants and generated water, the optimized distribution of air is crucial for improving battery performance. This layout ensures the highest efficiency in the distribution of the reactant gas (air), while being symmetrically surrounded by hydrogen and coolant channels, which helps maintain the uniformity of the physical fields (such as pressure and temperature) on the plate surface, thereby improving the utilization rate of the plates.

[0035] The reaction zone 20, located in the center of the plate, is equipped with a meandering air guide channel 21. This zone is the main site for electrochemical reactions, and its meandering guide channel design is intended to extend the air flow path, ensure sufficient contact between the air and the membrane electrode, and provide a channel for the discharge of water generated in the reaction.

[0036] In some embodiments, the angle of the air guide slit 21 at the bend is 120°. o -179 o This 120°-179° angle refers to the angle formed when the centerline of the air guide channel 21 changes its forward direction during a turn.

[0037] Please see Figure 1 and Figure 2 The meandering airflow channel 21 is composed of periodically spaced upper arcs 211 and lower arcs 212. This periodic meandering structure is the skeleton of the flow field design, which effectively extends the airflow path and ensures full contact between the reactant gas and the membrane electrode surface.

[0038] In some embodiments, the distribution period of the upper arc 211 and the lower arc 212 is 10-40 mm. The distribution period is defined as the straight-line distance between the vertices of two adjacent upper arcs 211 along the extension direction of the air guide groove 21. That is, the straight-line distance between the highest point of one upper arc and the highest point of the next upper arc, which is also the straight-line distance between the lowest point of one lower arc and the lowest point of the next lower arc.

[0039] The width of the air guide channel 21 at the lower arc 212 is smaller than its width at the non-lower arc locations, increasing the air velocity flowing through the lower arc 212. The lower arc 212 is the lowest point in the flow channel and the area most prone to liquid water accumulation. During the hydrogen-oxygen electrochemical reaction, water is continuously generated, some of which condenses into liquid and accumulates at the lower arc 212. By setting a variable-diameter lower arc 212 in the air guide channel 21, the air velocity increases as it passes through the lower arc 212, thereby carrying away the liquid water accumulated there. This variable-diameter design utilizes fluid mechanics principles: when air flows through a narrower channel, its velocity increases significantly. The increased airflow velocity generates stronger shear force, effectively sweeping away and carrying away the liquid water accumulated at the lower arc 212, fundamentally solving the problems of poor flow and water accumulation, and avoiding loss of reaction area.

[0040] To enable those skilled in the art to fully understand the beneficial effects of the technical feature of "reducing the groove width at the lower arc" in this invention, its drainage mechanism is explained in detail below: Liquid water accumulates primarily in the lowest lower arc region of the cathode channel, adhering to the surface of the gas diffusion layer and the channel walls in the form of a water film or droplets. In traditional constant-width channels, the airflow velocity is relatively uniform, and the shear force generated at the lower arc is often insufficient to overcome the adhesion and surface tension of the water droplets, resulting in the inability to remove the accumulated water in a timely manner. This invention actively reduces the channel width at the lower arc, causing a significant increase in the airflow velocity due to the contraction of the flow cross-section (based on the continuity principle and Venturi effect in fluid mechanics). The increase in airflow velocity is not merely to increase the flow rate; its effect is as follows: (1) Increased shear force at the gas-liquid interface: The shear force of the airflow acting on the surface of the droplet is proportional to the square of the flow velocity. The increase in local flow velocity amplifies the shear force applied to the water surface by a square multiple, thereby effectively disrupting the mechanical equilibrium of the water droplet and causing it to peel off from the wall. (2) Promoted atomization and carrying of water droplets: High-speed airflow can break the larger water droplets that have been peeled off into smaller droplets, or drag them into a liquid film flowing along the wall. These morphological transformations greatly reduce the resistance to movement of liquid water, making it easier for it to be carried by the airflow. (3) Formation of directional transport: The peeled and atomized liquid water moves forward along the meandering air guide channel 21 under the continuous push of the high-speed airflow, and is finally discharged from the cathode outlet of the fuel cell stack.

[0041] Therefore, this design does not rely on increasing the overall intake pressure (which would increase system power consumption), but instead optimizes the flow channel morphology to create a high-speed shear flow field locally in the key area of ​​water accumulation, achieving efficient active discharge of liquid water through "stripping-atomization-transportation" at the lowest energy cost.

[0042] In some embodiments, the ratio of the channel width at the non-lower arc 212 location to the channel width at the lower arc 212 location is 1-8. This ratio refers to the quotient of the channel width at the non-lower arc location and the channel width at the lower arc location, and its value ranges from 1 to 8 (inclusive of endpoint values). For clarity, it is defined as follows: Let Wn be the standard groove width of 212 at the non-lower arc.

[0043] Let Wb be the groove width at the lower arc 212.

[0044] The technical conditions defined in this embodiment are: 1≤Wn / Wb≤8.

[0045] This limitation has a clear technical meaning: (1) When the ratio is 1 (Wn=Wb): it means that the flow channel is designed with equal width, that is, the narrowing optimization of the present invention is not implemented at the lower arc 212. This is the theoretical lower limit of the ratio range.

[0046] (2) When the ratio is greater than 1 (Wn>Wb): it means that the groove width at the lower arc 212 has been narrowed according to the design of this invention. For example, when the ratio is 2, it means that the groove width at the lower arc is half of the standard groove width; when the ratio is 8, it means that the groove width at the lower arc 212 is one-eighth of the standard groove width, and the narrowing effect is most significant at this time.

[0047] (3) Significance of the ratio range: This range (1-8) defines an optimization design space. When the ratio is close to 1, the flow resistance is small but the drainage capacity is only slightly improved; when the ratio increases, the drainage capacity is enhanced but the local flow resistance also increases.

[0048] Please see Figure 3 A sloping protrusion 2111 is provided at the bottom of the groove at the upper arc 211. The function of this sloping protrusion 2111 is to actively guide the airflow. The sloping protrusion 2111 is constructed to generate a lifting force on the air when it flows through, guiding the air to generate an upward diffusion flow field towards the membrane electrode, thereby enhancing the gas mass transfer process at the hydrogen-oxygen electrochemical reaction interface. The sloping protrusion 2111 forces the reactant gas to rush towards the catalytic reaction interface, greatly enhancing the gas, proton, and electron transfer efficiency, thereby strengthening the gas mass transfer process at the hydrogen-oxygen electrochemical reaction interface.

[0049] In some embodiments, the slope of the sloping boss 2111 is 5°-30°, and the ratio of the depth of the air guide channel 21 to the height of the sloping boss 2111 is 1-10. This means that the quotient of the depth and height is between 1 and 10 (inclusive). That is, the height of the sloping boss 2111 is not greater than the depth of the air guide channel 21, and can be as low as one-tenth of its depth.

[0050] The reactant transition zone 30 is located on the plate between the inlet / outlet zone 10 and the reaction zone 20. This zone serves as a functional bridge connecting the inlet / outlet zone 10 and the reaction zone 20, and is responsible for the efficient distribution of the concentrated incoming reaction gas. Following the airflow direction, it contains, in sequence: an air tumbling port 31, an air diffusion zone 32, and multiple air buffer protrusions 33.

[0051] The air reversing orifice 31 receives air from the common air inlet 12 and changes its flow direction. As an airflow direction converter, the air reversing orifice 31 changes the airflow direction from perpendicular to the plate plane (the direction from the common inlet) to parallel to the plate plane (the direction into the flow field), preparing for subsequent uniform distribution. The air diffusion zone 32, adjacent to the air reversing orifice 31, performs primary uniform distribution of the air after the direction change. This zone acts as a wide buffer, allowing the air to diffuse rapidly and establish a uniform pressure distribution across its entire outlet width, creating a uniform pressure foundation for subsequent entry into each independent flow channel. Air buffer bosses 33 are positioned between the air diffusion zone 32 and the reaction zone 20. Their function is to perform secondary uniform distribution and stable delivery of the primary distributed air. These air buffer bosses 33 generate controllable local flow resistance, finely regulating the gas flowing downstream, ensuring that air enters the meandering air guide channel 21 uniformly and smoothly.

[0052] After entering through the common air inlet 12, the air first undergoes a 90-degree change in direction via the air reversing port 31; then it enters the air diffusion zone 32 for preliminary, macroscopic pressure equalization and distribution; next, it flows through the array of air buffer protrusions 33 for secondary, fine-tuned flow regulation; finally, the evenly distributed air enters each of the meandering air guide channels 21 in the reaction zone 20 to participate in the electrochemical reaction. These four parts are interconnected, together forming a highly efficient and uniform air distribution and reaction system.

[0053] In some embodiments, the air reversing waist hole 31 is located adjacent to and directly connected to the air common port 12 within the reactant transition region 30, and is used to change the flow direction of air from the air common port 12 from a direction perpendicular to the plate plane to a direction parallel to the plate plane.

[0054] The air diffusion zone 32 is a strip-shaped planar area set on both sides of the air reversing waist hole 31. The bottom surface of the air diffusion zone 32 is lower than the bottom surface of the air guide groove 21, and is used to receive and distribute the air from the air reversing waist hole 31 in a primary manner, and guide it to the air buffer boss 33.

[0055] The lower bottom surface creates a shallow cavity structure in three-dimensional space. When air rushes out from the air inverted waist hole 31, it can rapidly expand, decelerate, and fill the entire strip-shaped area within this cavity, achieving initial pressure equilibrium—this is the first-level distribution process.

[0056] This shallow cavity structure acts as a hub for convergence and redistribution, receiving concentrated airflow from the air-turning waist hole 31 and smoothly guiding it to multiple downstream air-buffered protrusions 33. It ensures that the air is delivered uniformly to subsequent distribution stages as a whole, rather than being randomly rushed into parts of the flow channel.

[0057] Air is first introduced into the shallowest cavity (air diffusion zone 32) at the lowest position to achieve rapid filling and initial pressure equalization; then, the homogenized airflow overflows forward and encounters an array of air buffer protrusions 33; the protrusion array throttles and redistributes the overflowing gas, ultimately guiding it evenly to the air guide channels 21 located at a higher bottom surface. This spatial coordination design of "lowering-overflowing-distributing" is the key to achieving uniform gas distribution.

[0058] Specifically, such as Figure 1 As shown, the air diffusion zone 32 is a continuous strip-shaped planar region extending on both sides of the air reversal aperture 31. This means that after the air flowing out of the air reversal aperture 31 fills the area directly in front of it, it immediately diffuses to the connected areas on the left and right sides until it fills the entire strip-shaped region. Therefore, air can reach these areas without obstruction through the flow within the plane.

[0059] Once the air fills the entire continuous, interconnected air diffusion zone 32, the pressure will rapidly reach equilibrium within a connected fluid region. Therefore, a highly uniform static pressure distribution will be formed along the entire leading edge of the air diffusion zone 32 (i.e., along the entire boundary line connecting with the array of air buffer bosses 33).

[0060] The gaps between each air buffer boss 33 expose their inlets to the same boundary of this uniform pressure field. Driven by the uniform inlet pressure, air will flow out from all the gaps between the bosses at essentially equal flow rates and enter their respective air guide channels 21. This is precisely the meaning of "first-level uniform distribution": it ensures that the driving pressure at the inlet of all downstream parallel flow channels is equal by establishing a uniform pressure boundary condition, thereby achieving uniform flow.

[0061] It should be noted that the air buffer boss 33 is not limited to the waist shape.

[0062] In some embodiments, the length of the air buffer boss 33 is 3-12 mm.

[0063] Multiple air buffer protrusions 33 are arranged in an array between the air diffusion area 32 and the air guide channel 21.

[0064] The air buffer boss 33 has an oblong cross-section and is used to perform secondary distribution and flow stabilization of the air after primary distribution in the air diffusion zone 32, and to uniformly deliver the air to each air guide groove 21. The structure of these air buffer bosses 33 directly determines the final distribution state of the air entering the reaction zone 20.

[0065] The "waist shape" refers to a shape whose outline is approximately a circle or ellipse stretched along its long axis, with symmetrical arcs on both sides of its long axis. Its overall shape is similar to a "dumbbell" or "spindle" in sports equipment.

[0066] The function of the air buffer protrusions 33 is to perform secondary distribution and flow stabilization on the air that has already been distributed once through the air diffusion zone 32. Although the airflow after the primary distribution is macroscopically more uniform, there may still be unevenness or disturbances in the airflow. The arrayed air buffer protrusions 33 form a porous resistance layer, which finely adjusts the airflow to ensure that the airflow and pressure flowing to each air guide channel 21 are basically consistent, while suppressing and eliminating large-scale eddies, thus playing a significant role in flow stabilization.

[0067] The cross-sectional shape of the air buffer boss 33 is waist-shaped. This streamlined design can achieve the throttling function while minimizing flow resistance, avoiding excessive pressure drop and eddies, and allowing air to smoothly bypass both sides of the air buffer boss 33 and enter the air guide groove 21.

[0068] Please continue reading. Figure 1 Multiple air buffer protrusions 33 are evenly spaced along the width of the plate, and the gap between each two adjacent air buffer protrusions 33 uniquely corresponds to and connects to the inlet of an air guide groove 21.

[0069] The array of uniformly spaced air buffer protrusions 33 ensures that the flow area and flow resistance of each gap are essentially the same. When air flows through this array from the upstream air diffuser zone 32, the airflow is forcibly divided into several streams with almost equal flow rates. This design achieves precise and uniform subdivision of the total airflow, which is the fundamental guarantee that air can be uniformly delivered to each air guide slot 21.

[0070] The air buffer boss 33 is the endpoint of the gas distribution process within the reactant transition region 30. The air flows through the air reversing hole 31, changes direction, undergoes initial diffusion and pressure equalization in the air diffusion region 32, and is finally precisely distributed into the meandering air guide channel 21 through the fixed flow channel inlet array formed by the gaps between the bosses, thus completing the entire process from centralized supply to uniform distribution.

[0071] The present invention also provides a fuel cell having at least one of the above-described fuel cell cathode plates. This fuel cell integrates the fuel cell cathode plate provided by the present invention. Specifically, the cathode side of the fuel cell has a complete airflow field system consisting of a reactant transition region 30 (including an air inversion perforation 31, an air diffusion region 32, and an air buffer boss 33) and an optimized reaction region 20 (including a meandering air guide groove with a variable-width lower arc and a sloping upper arc).

[0072] This invention achieves smooth and uniform air delivery from the common inlet to the reaction channel through a three-stage progressive structure consisting of an air-turning waist hole 31, an air diffusion zone 32, and an air buffer boss 33; by setting a narrow groove at the lower arc of the meandering channel, the flow velocity is increased to effectively enhance the water discharge capacity; and by setting a sloping boss 2111 at the upper arc, the airflow is actively guided to impact the membrane electrode, significantly enhancing the gas phase mass transfer process.

[0073] The multi-stage distribution system in the cathode plate ensures that air is delivered to the entire catalyst layer in an extremely uniform manner. This allows the cathode reaction of the fuel cell to proceed at a very uniform current density, avoiding local overload or insufficient reaction, and improving operational stability and lifespan.

[0074] The drainage design of the lower arc in the cathode plate can promptly and efficiently drain the water generated by the electrochemical reaction from the battery, significantly reducing the risk of battery performance degradation or even failure due to water accumulation in the flow channels. At the same time, uniform reaction and smooth drainage also contribute to the uniform distribution and dissipation of heat inside the battery.

[0075] The mass transfer enhancement design for the upper arc in the cathode plate directly increases the rate at which oxygen is transported to the catalyst surface, enabling the fuel cell to output higher power (higher power density) and exhibit higher operating efficiency within the same volume or weight.

[0076] Inside this fuel cell, the cathode plate works in conjunction with other components such as the membrane electrode assembly (MEA) and anode plate. The cathode plate is responsible for optimizing air supply, drainage, and mass transfer; the anode plate is responsible for hydrogen distribution; and the MEA is the site of the reaction. The superior performance of the cathode plate in this invention ensures that the chemical reaction of the entire fuel cell—the hydrogen-oxygen reaction—can proceed under optimal conditions. Its efficient drainage capacity ensures that the MEA is not flooded, and its enhanced mass transfer capacity ensures an adequate supply of reactants. Ultimately, all these improvements work synergistically to significantly improve the overall performance of the fuel cell (including power, efficiency, and durability).

[0077] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A fuel cell cathode plate, comprising a plate body, characterized in that, Also includes: The import / export area (10) is located at the edge of the plate and has multiple common openings that penetrate the plate. The reaction zone (20) is located in the center of the plate and is provided with a meandering air guide channel (21). The reactant transition region (30) is located on the plate between the inlet / outlet region (10) and the reaction region (20). According to the air flow direction, it is provided with an air overturning waist hole (31), an air diffusion zone (32) and multiple air buffer protrusions (33). The air-turning waist hole (31) is used to receive air from the common port and change the air flow direction, the air diffusion zone (32) is used to uniformly distribute the air in the first stage, and the air buffer boss (33) is used to uniformly distribute the air in the second stage and deliver the air to the air guide groove (21).

2. The fuel cell cathode plate according to claim 1, characterized in that, The plurality of the common ports include a hydrogen common port (11), an air common port (12), and a coolant common port (13); The air common port (12) is disposed between the hydrogen common port (11) and the coolant common port (13).

3. The fuel cell cathode plate according to claim 2, characterized in that, The air reversing waist hole (31) is located adjacent to and directly connected to the air common port (12) in the reactant transition area (30), and is used to change the flow direction of air from the air common port (12) from a direction perpendicular to the plate plane to a direction parallel to the plate plane.

4. The fuel cell cathode plate according to claim 3, characterized in that, The air diffusion zone (32) is a strip-shaped planar area set on both sides of the air reversing waist hole (31); The bottom surface of the air diffusion zone (32) is lower than the bottom surface of the air guide groove (21) for receiving and distributing air from the air reversing waist hole (31) and guiding it to the air buffer boss (33).

5. The fuel cell cathode plate according to claim 4, characterized in that, The air buffer protrusions (33) are multiple and arranged in an array between the air diffusion area (32) and the air guide groove (21); The cross-sectional shape of the air buffer boss (33) is waist-shaped. It is used to perform secondary distribution and flow stabilization of the air after it has been distributed once by the air diffusion zone (32), and to uniformly deliver the air to each of the air guide slots (21).

6. The fuel cell cathode plate according to claim 5, characterized in that, Multiple air buffer protrusions (33) are evenly spaced along the width direction of the plate, and the gap between each two adjacent air buffer protrusions (33) uniquely corresponds to and connects to the inlet of an air guide groove (21).

7. The fuel cell cathode plate according to claim 6, characterized in that, The meandering air guide channel (21) is composed of an upper arc (211) and a lower arc (212) arranged at periodic intervals.

8. The fuel cell cathode plate according to claim 7, characterized in that, The width of the air guide groove (21) at the lower arc (212) is smaller than its width at the non-lower arc, so as to increase the air velocity flowing through the lower arc (212).

9. The fuel cell cathode plate according to claim 8, characterized in that, A sloping boss (2111) is provided at the bottom of the groove at the upper arc (211). The sloping boss (2111) is configured to generate a lifting force on the air when it flows through it, guiding the air to generate an upward diffusion flow field toward the membrane electrode, thereby enhancing the gas mass transfer process at the hydrogen-oxygen electrochemical reaction interface.

10. A fuel point battery, characterized in that, It has at least one of the fuel cell cathode plates according to any one of claims 1-9.

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