Stack end plate, fuel cell stack and vehicle

Abstract

A stack end plate, a fuel cell stack, and a vehicle, belonging to the technical field of fuel cells. The stack end plate comprises an end plate body (1), wherein an end plate flow channel (11) runs through the inside of the end plate body (1), forming an inner port (121) and an outer port (131) on two end faces of the end plate respectively; the projections of the inner port (121) and the outer port (131) along the thickness of the end plate have a non-overlapping region; the aspect ratio of the inner port (121) is greater than that of the outer port (131); the side wall of the end plate flow channel is provided with a flow guiding inclined surface (111) opposite the outer port in the non-overlapping region, and the inside of the end plate flow channel is provided with flow dividing ribs (112) extending in the direction of medium flow.

Description

fuel cell stack end plates, fuel cell stacks and vehicles

[0001] Cross-references to related applications

[0002] This application is based on Chinese Patent Application No. CN202411030706.2, filed on July 30, 2024, and claims priority to that Chinese Patent Application, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of fuel cell technology, and particularly relates to a fuel cell stack end plate, a fuel cell stack, and a vehicle. Background Technology

[0004] As the power of a fuel cell stack increases, the required diameter of the gas and coolant channels increases significantly. Due to the limitation of the short side dimension of the endplate, the endplate with the channels arranged on it cannot meet the requirements. Generally, a distributed channel around the perimeter is chosen, but the length-to-width ratio of the channel increases significantly, requiring the channel to be divided into multiple channel cavities. Therefore, how to reduce flow resistance and how to control the uniform distribution of each channel cavity become urgent problems to be solved. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a fuel cell stack endplate, a fuel cell stack, and a vehicle, which enables a more uniform distribution of the gas-liquid medium entering the stack through the stack endplate under lower pressure loss, thus facilitating the consistent performance of the stack.

[0006] In a first aspect, this application provides an end plate for an electric fuel cell stack. The end plate includes an end plate body, and a through end plate channel is provided in the end plate body to form an inner port and an outer port on two end faces of the end plate, respectively. The projections of the inner port and the outer port in the thickness direction of the end plate have non-overlapping areas. The aspect ratio of the inner port is greater than that of the outer port. The sidewall of the end plate channel has a flow guiding slope opposite to the outer port in the non-overlapping area. The end plate channel has a flow diversion rib extending along the medium flow direction.

[0007] According to the end plate of the fuel cell stack in this application, in order to meet the gas consumption and cooling requirements of high-power fuel cells, the inner port is more elongated than the outer port. By setting the flow guide slope and the flow divider, the medium entering the fuel cell stack through the end plate is distributed more evenly with lower pressure loss, which is conducive to the consistent performance of the fuel cell stack.

[0008] In a second aspect, this application provides a fuel cell stack, including a stack endplate as described in any of the technical solutions in the first aspect.

[0009] According to the fuel cell stack of this application, by using the stack endplate as in the first aspect, it is easier to increase the power, and because the flow channel cavity distribution is more uniform, it is beneficial to the consistent performance of the stack and improve the working efficiency of the fuel cell stack.

[0010] Thirdly, this application provides a vehicle including a fuel cell stack as described in the second aspect, the fuel cell stack being used to provide electrical energy to the vehicle.

[0011] The vehicle according to this application improves overall vehicle performance and operational stability by using a fuel cell stack as described in the second aspect.

[0012] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0013] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0014] Figure 1 is a schematic diagram of the structure of the fuel cell stack end plate provided in an embodiment of this application;

[0015] Figure 2 is a schematic diagram of the cross-sectional structure at point AA in Figure 1;

[0016] Figure 3 is a schematic diagram of the cross-sectional structure at point BB in Figure 1;

[0017] Figure 4 is a partial structural schematic diagram of the fuel cell stack end plate provided in an embodiment of this application;

[0018] Figure 5 is one of the structural schematic diagrams of the original scheme of the endplate flow channel.

[0019] Figure label:

[0020] 1. End plate body; 11. End plate flow channel; 111. Guide slope; 112. Flow divider; 12. Inner end face; 121. Inner port; 122. Sealing groove; 13. Outer end face; 131. Outer port; 2. Manifold; 21. Manifold flow channel; 22. End plate interface; 23. Pipe interface. Embodiments of the present invention

[0021] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0022] A proton exchange membrane fuel cell (PEMFC) is a power generation device that directly converts the chemical energy in fuel into electrical energy. It has advantages such as low operating temperature, fast start-up, high specific power, simple structure and convenient operation. Therefore, fuel cells are widely used in the automotive industry, power generation, shipbuilding industry, aerospace, home power supply and other industries.

[0023] Bipolar plates and membrane electrode assemblies (MEAs) are crucial components of a fuel cell stack. Bipolar plates distribute fuel, conduct electricity, and support the MEAs, which are the sites of electrochemical reactions. A single fuel cell is also called a single cell. To improve the overall output power of the fuel cell, multiple single cells are typically stacked in series to form a fuel cell stack. End plates are divided into inlet end plates and blind end plates, located at opposite ends of the fuel cell stack. They, along with other fasteners, transmit the stack's clamping pressure. The end plates are connected to the current collectors and also provide sealing and insulation for the stack. Furthermore, the inlet end plate, connected to the inlet manifold, also distributes reactant gases and coolant.

[0024] To ensure optimal fuel cell stack performance, the design of low flow resistance and uniform distribution in the inlet endplate flow channels is crucial. In related technologies, the gas-liquid flow channel inlets of the fuel cell stack endplate are arranged on the two short sides of the endplate. This arrangement offers advantages such as simple flow channel structure, low pressure loss, and small sealing area. However, as the power of the fuel cell stack increases, the required flow area for the air and coolant flow channels increases significantly. Due to the limitations of the short side dimensions of the endplate, arranging the gas-liquid flow channels on the two short sides of the inlet endplate is no longer suitable. In this case, the flow channel inlets need to be arranged on the long side of the endplate, with the gas-liquid flow channels distributed around the perimeter of the inlet endplate to meet the stack power requirements. However, this arrangement significantly increases the aspect ratio of the flow channels, resulting in higher flow resistance after the gas-liquid medium enters the endplate through the pipes. Furthermore, to ensure uniform entry of the reactant gas or coolant into the stack and maintain consistent stack performance, the flow channel typically needs to be divided into multiple flow channel chambers, making it difficult to guarantee uniform flow rate across each chamber. Therefore, how to reduce flow resistance and how to control the uniform distribution of each flow channel cavity have become urgent problems to be solved.

[0025] Based on the above considerations, this application proposes an end plate for fuel cell stacks. This end plate is applied to the inlet end plate, which enables the gas-liquid medium entering the fuel cell stack through the end plate to be distributed more evenly with lower pressure loss, thus facilitating the consistent performance of the fuel cell stack.

[0026] The fuel cell stack end plate according to an embodiment of this application is described below with reference to Figures 1-4.

[0027] Please refer to Figures 1, 2, and 3. The fuel cell stack end plate of this embodiment includes an end plate body 1. The end plate body 1 has a through end plate flow channel 11 to form an inner port 121 and an outer port 131 on the two end faces of the end plate, respectively. The projections of the inner port 121 and the outer port 131 in the thickness direction of the end plate have non-overlapping areas. The aspect ratio of the inner port 121 is greater than that of the outer port 131. The sidewall of the end plate flow channel 11 has a flow guiding slope 111 opposite to the outer port 131 in the non-overlapping area. The end plate flow channel 11 has a flow diversion rib 112 extending along the medium flow direction.

[0028] It is understood that the two end faces of the end plate are the inner end face 12 close to the core and the outer end face 13 far from the core. The end plate flow channel 11 extends through the end plate body 1 along the thickness direction to form an inner port 121 on the inner end face 12 for communicating with the internal flow channel cavity of the fuel cell stack, and an outer port 131 on the outer end face 13 for communicating with external pipes.

[0029] The aspect ratio of the inner port 121 is greater than that of the outer port 131. This is because the internal flow channels of the fuel cell stack are distributed around the periphery of the endplate, resulting in a generally elongated cross-section to minimize space occupation while ensuring flow rate. Therefore, the aspect ratio of the inner port 121 is generally larger. Conversely, the external pipes are generally circular, and to facilitate connection between the outer port 131 and the external pipes, the aspect ratio of the outer port 131 is generally smaller. This difference in shape between the inner port 121 and the outer port 131 is understandable. However, to facilitate the shape variation of the inner port 121 and the outer port 131, their length directions are the same.

[0030] It should be noted that the length direction indicated in Figure 2 refers to the width direction of the inner port 121 and outer port 131 corresponding to the end plate flow channel 11 in the figure, and the width direction indicated in Figure 3 refers to the length direction of the inner port 121 and outer port 131 corresponding to the end plate flow channel 11 in the figure, rather than the length and width direction of the end plate body 1.

[0031] The inner port 121 and the outer port 131 have different shapes, and the inner port 121 and the outer port 131 are at least partially misaligned in the thickness direction of the end plate to reduce the size difference between the inner port 121 and the outer port 131. By setting a flow guide slope 111 opposite to the outer port 131 in the non-overlapping area on the side wall of the end plate flow channel 11, that is, the flow guide slope 111 can be seen from the side of the outer port 131, so that after the gas-liquid medium enters the end plate flow channel 11 from the outer port 131, at least part of it will contact the flow guide slope 111. The flow guide slope 111 can play a certain guiding role to reduce the flow resistance during the cross-sectional change of the end plate flow channel 11.

[0032] It should be noted that the flow divider 112 corresponds to the separator between multiple flow channels of the same medium inside the fuel cell. By setting the flow divider 112 in the end plate flow channel 11, the gas and liquid medium in the end plate flow channel 11 is diverted into different flow channels, thereby improving the uniformity of flow in each flow channel and reducing flow resistance.

[0033] It should be further noted that the end plate flow channel 11 can be one of the following: cooling medium inlet channel, cooling medium outlet channel, air inlet channel, air outlet channel, hydrogen inlet channel, and hydrogen outlet channel, without any specific limitation.

[0034] According to the embodiment of this application, in order to meet the gas consumption and cooling requirements of high-power fuel cells, the inner port 121 is more elongated than the outer port 131. By setting the flow guiding slope 111 and the flow splitting rib 112, the medium entering the fuel cell through the fuel cell end plate is distributed more evenly with lower pressure loss, which is conducive to the consistent performance of the fuel cell.

[0035] In some embodiments, the endplate body 1 can be made of aluminum-plastic composite material. The endplate body 1 is made of aluminum alloy to ensure the structural strength of the endplate. The sidewall portion of the endplate flow channel 11 within the endplate body 1 is made of plastic to ensure insulation and safety performance. Furthermore, the endplate flow channel 11 is provided with flow dividers 112, eliminating the need for an additional flow equalization plate. The fuel cell stack endplate of this application serves both to ensure the structural strength of the fuel cell and to allow for medium flow while ensuring insulation. Therefore, the fuel cell stack endplate of this application can be a three-in-one design of the shell endplate, air inlet endplate, and insulation endplate, reducing the number of independent components required for the fuel cell system. This not only simplifies the system layout and assembly process but also helps to reduce potential leakage risks and maintenance costs.

[0036] Please refer to Figures 2 and 3. According to some embodiments of this application, the dimension of the end plate flow channel 11 in the width direction of the inner port 121 can decrease along the direction of medium flow, and the dimension of the end plate flow channel 11 in the length direction of the inner port 121 can increase along the direction of medium flow, so that the guide slope 111 is inclined along the width direction of the inner port 121.

[0037] It should be noted that, in order to meet the requirements of high-power fuel cells, the diameter of the external pipe is generally large to ensure the flow rate of the gas-liquid medium. In order to adapt to the large flow rate, the size of the outer port 131 of the end plate flow channel 11 is also large. Therefore, the width dimension of the outer port 131 is larger than the width dimension of the inner port 121, and the length dimension of the outer port 131 is smaller than the length dimension of the inner port 121.

[0038] Therefore, the dimension of the endplate flow channel 11 decreases in the width direction of the inner port 121 along the direction of medium flow, and increases in the length direction of the inner port 121 along the direction of medium flow, making the endplate flow channel 11 gradually narrower and longer. It can be understood that, in order to improve the uniformity of each flow channel cavity, the outer port 131 is centered in the length direction of the inner port 121, so that the guide slope 111 is inclined along the width direction of the inner port 121, which facilitates the guidance of the gas-liquid medium entering the endplate flow channel 11.

[0039] Please refer to Figure 2. According to some embodiments of this application, the flow guiding slope 111 can be a smooth curved surface. The flow guiding slope 111 is provided on the side wall of the end plate channel 11 facing the center of the end plate body 1. The side wall of the end plate channel 11 facing the edge of the end plate body 1 is a plane.

[0040] By setting the guide ramp 111 as a smooth curved surface, the resistance when the gas-liquid medium collides with the guide ramp 111 is reduced. It is understood that the flow channel cavity is generally set on the periphery of the fuel cell to reduce space occupation. By setting the guide ramp 111 on the side wall of the end plate flow channel 11 facing the center of the end plate body 1, the flow channel cavity corresponding to the inner port 121 can be closer to the periphery of the fuel cell, and the connection of the manifold 2 on the outer end face 13 of the stack end plate is facilitated.

[0041] By setting the sidewall of the end plate flow channel 11 toward the edge of the end plate body 1 as a plane to reduce flow resistance, it can be understood that the plane extends along the thickness direction of the end plate.

[0042] According to some embodiments of this application, the flow guiding slope 111 can be connected to the inner port 121 and the outer port 131 via a circular arc surface transition. By providing a circular arc surface transition connection, flow resistance is reduced.

[0043] Referring to Figure 2, according to some embodiments of this application, the flow guiding slope 111 extends inward from the outer port 131 and is connected to the inner port 121 via an arc surface transition. The arc surface transition connection reduces flow resistance.

[0044] For example, the outer port 131 can be a composite shape of a semi-circular arc and a rectangle, and the inner port 121 can be rectangular. The semi-circular arc portion of the outer port 131 is located on one side near the center of the end plate body 1. The rectangular side of the outer port 131 is connected to one side plane of the inner port 121. The end of the flow guide slope 111 near the outer port 131 is connected to the semi-circular arc edge of the outer port 131. The four side walls of the end plate flow channel 11 near the inner port 121 can all be planar. The flow guide slope 111 and the side wall near the inner port 121 are connected by a circular arc surface to reduce flow resistance.

[0045] Referring to Figure 2, according to some embodiments of this application, the height of the guide slope 111 is h2, and the dimension of the guide slope 111 in the width direction of the inner port 121 is d6, which satisfies:

[0046] 0.4≤h2 / d6≤0.6.

[0047] Understandably, a lower slope of the guide slope 111 results in greater flow resistance, but it is beneficial for the size design of the outer port 131, allowing for a larger flow guiding area within a limited height range. Conversely, a higher slope of the guide slope 111 results in lower flow resistance, but a smaller coverage area, also leading to a smaller flow guiding area within a limited height range. By limiting the ratio of the height to the width of the guide slope 111, the flow guiding area can be maximized while maintaining low flow resistance, facilitating the shape design of the outer port 131 and the inner port 121, and improving the flow guiding effect.

[0048] The value range of h2 / d6 is [0.4, 0.6]. For example, h2 / d6 can take the values ​​of 0.4, 0.42, 0.45, 0.47, 0.5, 0.52, 0.55, 0.57, 0.6 or other ratios between 0.4 and 0.6. No specific limit is imposed here.

[0049] Please refer to Figure 3. According to some embodiments of this application, at least two flow dividers 112 may be provided. At least two flow dividers 112 may be provided at one end of the end plate flow channel 11 near the inner port 121 and spaced apart along the length direction of the inner port 121 to divide the inner port 121 into multiple inlet ports distributed along the length direction.

[0050] When the length dimension of the flow section on the long side of the end plate is large, multiple flow channel cavities are generally provided. By setting multiple flow dividers 112, the inner section is divided into multiple inlet ports distributed along its length direction. The multiple inlet ports can be connected to the multiple flow channel cavities respectively.

[0051] It should be noted that the number of flow dividers 112 is not limited here; there can be two, three, four, or more, depending on the overall design plan of the fuel cell stack.

[0052] As shown in Figure 3, in some embodiments, the end of the flow divider 112 near the outer port 131 is spaced apart from the outer port 131. Positioning the flow divider 112 near the inner port 121 ensures that the fluid is only divided when approaching the inner port 121, thus reducing mixing and interference within the endplate channel 11 and resulting in more uniform flow distribution. Furthermore, by spaced the flow divider 112 from the outer port 131, the medium has more space for acceleration and stabilization within the endplate channel 11, reducing pressure loss. The medium only encounters resistance when flowing near the inner port 121, allowing for better utilization of its kinetic energy. This also makes the flow path within the endplate channel 11 more rational, helping to optimize the flow state, reduce eddies and turbulence, and thus improve the efficiency and stability of the entire system.

[0053] Please refer to Figure 3. According to some embodiments of this application, there may be two diversion ribs 112. The two diversion ribs 112 divide the inner port 121 into three inlet ports distributed along the length direction of the end plate body 1. The lengths of the inlet ports at both ends are d1 and d3, respectively, and the length of the inlet port in the middle is d2. It can satisfy: d1=d3>d2.

[0054] It is understandable that, since the middle inlet is directly opposite the outer port 131, the flow resistance of the middle inlet is relatively smaller. By setting the size of the inlets at both ends to be the same, the flow rates of the two inlets at both ends are relatively consistent. By setting the size of the middle inlet to be smaller than the size of the inlets at both ends, the flow rate of the middle inlet is limited while the flow resistance of the middle inlet is smaller, thus ensuring that the flow rate of the middle inlet is relatively consistent with the flow rates of the inlets at both ends.

[0055] In some embodiments, the following condition can be met: 1.1 ≤ d1 / d2 ≤ 1.3. By limiting the range of the ratio between the lengths of the two end inlets and the length of the middle inlet, the uniformity of the flow rate at the three inlets can be ensured.

[0056] The value range of d1 / d2 is [1.1, 1.3]. For example, d1 / d2 can take the values ​​of 1.1, 1.12, 1.15, 1.17, 1.2, 1.22, 1.25, 1.27, 1.3 or other values ​​between 1.1 and 1.3, without any specific limitation here.

[0057] Please refer to Figure 3. According to some embodiments of this application, the spacing between the two diversion ribs 112 can increase along the direction of medium flow. The spacing between the two diversion ribs 112 near the outer port 131 is d4, and the length of the outer port 131 is d5, which can satisfy: 0.2≤d4 / d5≤0.3.

[0058] Because the length of the inner port 121 is greater than the length of the outer port 131, in order to improve the uniformity of the flow split, the spacing between the two flow splitting ribs 112 is set to increase along the direction of medium flow, that is, from the outer port 131 to the inner port 121, so that the cross-sectional dimensions of the three flow splitting cavities defined by the flow splitting ribs 112 are relatively average in the direction of medium flow.

[0059] The flow divider 112 is arc-shaped to reduce flow resistance and match the overall shape design of the end plate flow channel 11.

[0060] By limiting the dimensional ratio of the spacing of the flow divider 112 near the outer port 131 to the length of the outer port 131, the flow rate entering the middle flow channel cavity and the two side flow channel cavities is reasonably distributed.

[0061] The value range of d4 / d5 is [0.2, 0.3]. For example, d4 / d5 can take the values ​​of 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3 or other values ​​between 0.2 and 0.3. No specific limitation is made here.

[0062] Please refer to Figure 3. In some embodiments, the total length of the flow section of the inner port 121 is d1+d2+d3, and the length of the outer port 131 is d5, which can satisfy d5 / (d1+d2+d3)≥0.5.

[0063] By limiting the ratio of the length of the outer port 131 to that of the inner port 121 to be no less than 0.5, it is beneficial to reduce flow resistance, improve the uniformity of flow distribution, and enhance the consistency of fuel cell stack performance.

[0064] Please refer to Figure 3. According to some embodiments of this application, the height of the diversion rib 112 is h1, and the thickness of the end plate body 1 is H, which can satisfy: 0.3≤h1 / H≤0.6.

[0065] The flow divider 112 is spaced apart from the outer port 131 of the end plate. By limiting the ratio of the height of the flow divider 112 to the thickness of the end plate body 1, it is ensured that the medium has enough distance to accelerate and stabilize after entering the end plate flow channel 11. This can reduce pressure loss and improve the uniformity of flow distribution, as well as the uniformity of medium flow rate in each flow channel cavity.

[0066] The value range of h1 / H is [0.3, 0.6]. For example, h1 / H can take the values ​​of 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6 or other values ​​between 0.3 and 0.6, without any specific limitation.

[0067] Please refer to Figures 1, 2, and 3. According to some embodiments of this application, the fuel cell stack end plate further includes a manifold 2. The manifold 2 is installed on the outer end face 13 of the end plate body 1. The manifold 2 has a manifold flow channel 21. Different surfaces of the manifold 2 form an end plate interface 22 and a pipe interface 23 that communicate with the manifold flow channel 21. The pipe interface 23 has a different shape from the end plate interface 22. The end plate interface 22 communicates with the outer port 131 and has the same shape. The manifold flow channel 21 and the end plate flow channel 11 communicate to jointly form a transfer flow channel.

[0068] Because the endplate interface 22 and the pipe interface 23 have different shapes, this design allows for flexible connection between the inlet endplate and the external piping system. It is understandable that external pipelines are generally circular, while the shape of the flow channels within the reactor core varies greatly depending on the actual needs of the core. Therefore, to transfer the circular flow cross-section to the core's flow channels, and to minimize flow resistance and improve core performance, the rationality of the entire transfer channel design must be ensured.

[0069] During design and production, the end plate body 1 and manifold 2 can be designed as a single integrated component for the transfer flow channel. The transfer flow channel can then be further divided into the end plate flow channel 11 within the end plate body 1 and the manifold flow channel 21 within the manifold 2. This increases the design space for the transfer flow channel. Furthermore, when considering the overall size of the fuel cell stack, the size of the manifold 2 is generally not considered, thus the flow channel of the manifold 2 will not increase the size of the fuel cell stack. Because part of the transfer flow channel is designed within the manifold 2, the length of the end plate flow channel 11 can be compressed, and the thickness of the end plate body 1 can be thinner, thereby controlling the size of the fuel cell stack. Moreover, when the fuel cell stack is applied to the entire system, the manifold flow channel 21 can be reused in the system piping design. Compared to designing the flow channels within the end plate body 1 and the pipe fittings separately, this application can ensure relatively consistent gas-liquid parameters during fuel cell stack testing and system testing, resulting in more accurate fuel cell stack test results, improved production and development efficiency, and enhanced product quality.

[0070] By integrating a manifold 2 onto the endplate body 1 and providing an endplate interface 22 and a pipe interface 23 that communicate with the manifold flow channel 21, this design can effectively guide and distribute the gas-liquid medium entering the fuel cell. The connection between the manifold flow channel 21 and the endplate flow channel 11 forms a transfer flow channel, which helps to achieve a more uniform and efficient distribution, thereby improving the overall performance of the fuel cell.

[0071] In some embodiments, a sealing element is provided between the end plate body 1 and the manifold 2 to ensure the sealing of the connection surface between the end plate body 1 and the manifold 2.

[0072] Please refer to Figures 2 and 3. In some embodiments, the pipe interface 23 can be circular, and the diameter of the pipe interface 23 is D, which can satisfy 0.4≤d4 / D≤0.6.

[0073] The pipe interface 23 may at least partially correspond to the end of the diverter 112 near the outer port 131. By limiting the ratio of the spacing of the diverter 112 near the outer port 131 to the diameter of the pipe interface 23, the uniformity of flow distribution is improved.

[0074] The value of d4 / D ranges from [0.4, 0.6]. For example, d4 / D can take the values ​​of 0.4, 0.45, 0.5, 0.55, 0.6 or other values ​​between 0.4 and 0.6, without any specific limitation.

[0075] Please refer to Figures 2, 3, and 4. In some embodiments, a sealing groove 122 may be provided on the inner end face 12 of the end plate body 1, and the sealing groove 122 surrounds the inner port 121. Since there is no need to set up a flow equalization plate in this solution, the sealing groove 122 only needs to seal the area of ​​the inner port 121, reducing the sealing area between the end plate body 1 and the flow collector, reducing the contact area between the flow collector and the medium, reducing the corrosion resistance requirements of the flow collector, reducing production costs, and improving product durability.

[0076] This application also provides a fuel cell stack, including a stack end plate as described in any of the above technical solutions.

[0077] It should be noted that the fuel cell stack end plate is the air inlet end plate of the fuel cell stack. Since the fuel cell end plate of this embodiment includes the fuel cell stack end plate described in any of the above technical solutions, it possesses the technical features and effects of the fuel cell stack end plate described in any of the above technical solutions, and will not be elaborated upon here.

[0078] Please refer to Table 1 and Figure 5. Figure 5 shows the original scheme of the endplate flow channel. According to the fuel cell stack endplate provided in the embodiment of this application, compared with the original scheme in Figure 5 without the flow guide slope, the overall stack pressure drop of the fuel cell stack decreases by 7.2 kPa, thereby improving the reaction efficiency and output power of the fuel cell and improving the overall energy efficiency ratio. Among them, the specific flow non-uniformity reflects the distribution of the flow in the three chambers. The specific flow non-uniformity (absolute value) of the three flow channels in the core is lower, and the flow distribution in the three flow channels is more uniform. Reflected on the whole stack, the overall stack flow non-uniformity decreases by 1-2 percentage points, the core fluid distribution is better, and the consistency of stack performance is better.

[0079]

[0080] According to the embodiments of this application, the fuel cell stack can achieve increased power by using the stack endplate of any of the above technical solutions, and because the flow channel cavity distribution is more uniform, it is beneficial to the consistent performance of the stack and improve the working efficiency of the fuel cell stack.

[0081] This application also provides a vehicle including a fuel cell stack as described in any of the above technical solutions, the fuel cell stack being used to provide electrical energy to the vehicle.

[0082] It should be noted that, since the vehicle in this application embodiment includes the fuel cell stack described in any of the above technical solutions, it has the technical features and effects of the fuel cell stack described in any of the above technical solutions, which will not be elaborated here.

[0083] The vehicle provided according to the embodiments of this application can improve the overall performance and operational stability of the vehicle by using a fuel cell stack of any of the above technical solutions.

[0084] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0085] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0086] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0087] In the description of this application, "multiple" means two or more.

[0088] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0089] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0091] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A stack end plate comprising an end plate body, a through end plate flow channel being provided in the end plate body to form an inner port and an outer port on two end faces of the end plate respectively, a non-overlapping area being provided between projections of the inner port and the outer port in a thickness direction of the end plate, an aspect ratio of the inner port being greater than an aspect ratio of the outer port, a side wall of the end plate flow channel being provided with a flow guiding inclined surface opposite to the outer port in the non-overlapping area, and a flow dividing rib being provided in the end plate flow channel and extending in a medium flow direction.

2. The stack end plate according to claim 1, wherein a size of the end plate flow channel in a width direction of the inner port decreases along the medium flow direction, and a size of the end plate flow channel in a length direction of the inner port increases along the medium flow direction, so that the flow guiding inclined surface is inclined in the width direction of the inner port.

3. The stack end plate according to claim 2, wherein the flow guiding inclined surface is a smooth curved surface, the flow guiding inclined surface is provided on a side wall of the end plate flow channel close to a center of the end plate body, and a side wall of the end plate flow channel close to an edge of the end plate body is a flat surface; and / or, the flow guiding inclined surface is connected to the inner port and the outer port through a circular arc surface, or the flow guiding inclined surface extends inwardly from the outer port and is connected to the inner port through a circular arc surface.

4. The stack end plate according to claim 2, wherein a height of the flow guiding inclined surface is h2, a size of the flow guiding inclined surface in the width direction of the inner port is d6, and 0.4≤h2 / d6≤0.6 is satisfied.

5. The stack end plate according to claim 1, wherein at least two flow dividing ribs are provided in the end plate flow channel, the at least two flow dividing ribs are provided at one end of the end plate flow channel close to the inner port and are spaced apart in the length direction of the inner port, so as to divide the inner port into a plurality of stack inlet ports distributed in the length direction, lengths of the stack inlet ports at two ends are d1 and d3 respectively, a length of a stack inlet port in the middle is d2, and d1=d3>d2 is satisfied.

7. The stack end plate according to claim 6, wherein a spacing between the two flow dividing ribs increases along the medium flow direction, a spacing between the two flow dividing ribs close to the outer port is d4, a length of the outer port is d5, and 0.2≤d4 / d5≤0.3 is satisfied; and / or, a height of the flow dividing rib is h1, a thickness of the end plate body is H, and 0.3≤h1 / H≤0.6 is satisfied.

8. The stack end plate according to any one of claims 1-7, further comprising a manifold mounted on an outer end face of the end plate body, a manifold flow channel being provided in the manifold, different surfaces of the manifold form an end plate interface and a pipe interface in communication with the manifold flow channel, the pipe interface and the end plate interface are different in shape, the end plate interface is in communication with the outer port and is the same in shape, and the manifold flow channel and the end plate flow channel are in communication to jointly constitute a transfer flow channel.

6. The stack end plate of claim 5, said flow divider ribs being provided in two, two said flow divider ribs dividing said inner port into three said in-stack openings distributed along the length of said end plate body, wherein, 9. A fuel cell stack comprising the stack end plate according to any one of claims 1-8. ​ ​ ​ ​ ​ ​ ​ 10. A vehicle comprising a fuel cell stack as claimed in claim 9 for providing electrical power to the vehicle.

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