Longitudinal multi-connection polar plate and fuel stack

Abstract

The invention discloses a longitudinal multi-connected polar plate and a fuel stack, and relates to the technical field of fuel cells, the longitudinal multi-connected polar plate comprises a polar plate body, the polar plate body is provided with a total active area and two main pipe port areas, the total active area comprises N sub-active areas which are sequentially connected along the longitudinal direction, the header pipe opening area comprises gas openings and liquid openings which are sequentially and alternately arranged at intervals in the longitudinal direction. In each header pipe port area, the number of the gas ports is N + 1, the number of the liquid ports is N, one liquid port is formed between every two adjacent gas ports, the gas port between every two adjacent liquid ports is set as a shared gas port, the shared gas port is located between every two adjacent sub-active areas, the shared gas port is communicated with the gas flow channels of the two sub-active areas at the same time, and the gas flow channels of the two sub-active areas are communicated with the gas flow channels of the two sub-active areas. And the liquid ports are communicated with the cooling liquid flow channels of the sub-active regions in a one-to-one correspondence manner. Part of long edge sealing and frame areas are removed, the number of the air ports of the polar plate body is changed from 4N to 2N + 2 in a mode of locally combining the air ports, and the utilization rate of the active area of the polar plate is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a longitudinal multi-connected electrode plate and a fuel cell stack. Background Art

[0002] Hydrogen fuel cells, as a clean energy source with no carbon emissions or harmful substances, can be applied in the transportation sector. Given the increasing market demand for fuel cell power and the strict spatial constraints of fuel cell placement in vehicles, the volumetric power density of the fuel cell stack has become a key indicator of fuel cell performance. Conventional fuel cells limit the active area of ​​a single cell, resulting in low output power. High power requirements require stacking multiple cells, resulting in a low volumetric power density of the fuel cell stack.

[0003] As one of the key components of a fuel cell stack, the plate has the functions of separating battery cells, transporting reaction gases, providing electrical connections, removing water by-products, dissipating reaction heat, bearing stacking forces, and sealing. It accounts for more than 50% of the total mass of the stack and about 30% of the total cost of the stack. In the context of a market with increasing power demand, the demand for the active area of ​​the plate also increases. When the active area of ​​the plate expands to a certain extent, it will be difficult to ensure the uniformity of the plate, and then it will be difficult to ensure the performance of the stack. Summary of the Invention The purpose of the present invention is to provide a longitudinal multi-electrode plate and a fuel cell stack to solve one or more technical problems existing in the prior art and at least provide a beneficial option or create conditions.

[0004] The technical solutions adopted to solve the above technical problems are: The present invention provides a longitudinal multi-electrode plate, comprising: A plate body, the plate body comprising a total active area extending longitudinally, and two main pipe port areas located on two longitudinal sides of the total active area, the total active area comprising N sub-active areas sequentially connected in the longitudinal direction, wherein N is greater than or equal to 3, and the main pipe port areas comprising gas ports and liquid ports alternately arranged in the longitudinal direction; In each of the main pipe port areas, the number of the gas ports is N+1, the number of the liquid ports is N, there is one liquid port between each adjacent gas port, the gas port between the two adjacent liquid ports is set as a common gas port, the common gas port is located between the two adjacent sub-active areas, the common gas port is simultaneously connected to the gas flow channels of the two sub-active areas, and the liquid port is connected to the cooling liquid flow channels of the sub-active areas in a one-to-one correspondence.

[0005] The beneficial effects of the longitudinal multi-electrode plate of the present invention are: The total active area in the present invention is formed by connecting N sub-active areas in sequence along the longitudinal direction, removing part of the long side seal and frame area, increasing the active area of ​​the single cell, improving the utilization rate of the active area of ​​the plate, and reducing the cost of the plate material. In addition, each sub-active area corresponds to a liquid port and a gas port, and a common gas port is set between two adjacent sub-active areas. The common gas port is simultaneously connected to the gas flow path of the two adjacent sub-active areas. By locally merging the gas ports, the number of gas ports of the plate body is changed from the previous 4N to 2N+2, further improving the utilization rate of the active area of ​​the plate and reducing the number of gas ports. For plates with large active areas, it is beneficial to gas distribution and ensure the uniformity of the plate. While ensuring the uniformity of fuel cells with large active areas, the present invention also effectively improves the utilization rate of the active area of ​​the plate and increases the volume power density.

[0006] As a further improvement of the above technical solution, the area of ​​the common air port is larger than the areas of the air ports located at the longitudinal ends of the main pipe port area.

[0007] As a further improvement of the above technical solution, the two main pipe orifice areas include a first main pipe orifice area and a second main pipe orifice area, the liquid inlet in the first main pipe orifice area is a cooling liquid inlet, and the liquid inlet in the second main pipe orifice area is a cooling liquid outlet, and the cooling liquid inlet and the cooling liquid outlet are respectively provided at the center position of the two lateral ends of each sub-active area.

[0008] As a further improvement of the above technical solution, in the first manifold port area, the two gas ports arranged adjacent to the coolant inlet are an air inlet and a hydrogen outlet respectively; In the second manifold port area, the two gas ports adjacent to the coolant outlet are a hydrogen inlet and an air outlet respectively.

[0009] As a further improvement of the above technical solution, the air inlet and the hydrogen inlet are arranged opposite to each other in the transverse direction, and the hydrogen outlet and the air outlet are arranged opposite to each other in the transverse direction.

[0010] As a further improvement of the above technical solution, the positions of the air inlet and the air outlet are arranged in a centrally symmetrical manner with respect to the center of the total active area.

[0011] As a further improvement of the above technical solution, the positions of the hydrogen outlet and the hydrogen inlet are arranged in a centrally symmetrical manner with respect to the center of the total active area.

[0012] As a further improvement of the above technical solution, the coolant inlet and the coolant outlet are arranged in a centrally symmetrical manner with respect to the center of the sub-active area.

[0013] As a further improvement of the above technical solution, the electrode plate body is formed by integral stamping.

[0014] In addition, the present invention also proposes a fuel cell stack, comprising a plurality of the aforementioned longitudinal multi-connected plates, wherein the plurality of the aforementioned longitudinal multi-connected plates are stacked in sequence, and a proton membrane group is provided between two adjacent plate bodies.

[0015] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a schematic structural diagram of an embodiment of the original electrode plate solution; Figure 2 This is a structural diagram of an embodiment of the longitudinal triple electrode plate provided by the present invention; Figure 3 Schematic diagram comparing the longitudinal N-connected electrode plate provided by the present invention with the original splicing solution; Figure 4 Schematic diagram comparing the longitudinal triple electrode plate provided by the present invention and the original splicing solution; Figure 5 The figure is a schematic diagram of the gas flow on the air side of an embodiment of the longitudinal triple electrode plate provided by the present invention.

[0017] Figure Number: Plate body 100; total active area 110; sub-active area 111; first main pipe port area 120; coolant inlet 121; air inlet 122; hydrogen outlet 123; shared air inlet 124; shared hydrogen outlet 125; second main pipe port area 130; coolant outlet 131; hydrogen inlet 132; air outlet 133; shared air outlet 134; shared hydrogen inlet 135. DETAILED DESCRIPTION

[0018] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0019] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] In the description of the present invention, "a plurality" refers to more than two. The use of "first" or "second" is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of the indicated technical features, or implicitly indicating the order of the indicated technical features.

[0021] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0022] The technical solutions of the present invention will be described clearly and completely below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of the present invention, not all embodiments.

[0023] The current plate concept scheme on the market (hereinafter referred to as the original scheme) is basically as follows: Figure 1 As shown: there is one water cavity inlet / outlet, one hydrogen cavity inlet / outlet, and one cavity inlet / outlet. Since the plate accounts for a large proportion of the cost, volume and weight of the fuel cell stack, the size of the plate should be as small as possible to meet the fixed power requirement, that is, the active area utilization rate of the plate (η=S 极板活性面积 / S 极板最大外形面积 ) The larger the better. The utilization rate of the active area of ​​the plate in the original solution is basically between 45% and 50%, and the area utilization rate is relatively small. The battery stack designed according to the original plate solution is larger in size, with more stacked pieces, and the battery stack indicator - volume power density is small, which has no market competitiveness; in the context of increasing power demand in the market, the demand for active area of ​​the plate also increases synchronously. When the active area of ​​the plate in the original solution expands to a certain extent, it will be difficult to ensure the uniformity of the plate, and then it will be difficult to ensure the performance of the battery stack; the battery stacking solution designed according to the original solution is inefficient and the assembly cycle is slow.

[0024] Therefore, the present invention proposes a longitudinal multi-connected electrode plate, which reduces the sealing and frame size of some long sides of the electrode plate and optimizes the interface design. The purpose is to ensure the uniformity of fuel cells with large active areas while effectively improving the utilization rate of the active area of ​​the electrode plate, increasing the volume power density and reducing the cost of the electrode plate material, providing a new solution for improving the stacking efficiency and rhythm of the stack.

[0025] like Figure 2As shown, the longitudinal multi-connected electrode plate of the present invention includes: an electrode body 100, wherein the electrode body 100 is provided with a total active area 110 extending in the longitudinal direction, and two main pipe opening areas respectively located on two longitudinal sides of the total active area 110, the total active area 110 includes N sub-active areas 111 sequentially connected in the longitudinal direction, where N is greater than or equal to 3, and the main pipe opening area includes gas ports and liquid ports alternately arranged in the longitudinal direction; In the main pipe port area, the number of gas ports is N+1, the number of liquid ports is N, there is a liquid port between each adjacent gas port, the gas port between the two adjacent liquid ports is set as a common gas port, the common gas port is located between the two adjacent sub-active areas 111, the common gas port is connected to the gas flow channels of the two sub-active areas 111 at the same time, and the liquid port is connected to the cooling liquid flow channels of the sub-active areas 111 one by one.

[0026] The total active area 110 is formed by connecting N sub-active areas 111 in sequence along the longitudinal direction, removing part of the long side seal and frame area, thereby increasing the active area of ​​the single cell, increasing the utilization rate of the active area of ​​the plate, and reducing the cost of the plate material. In addition, each sub-active area 111 corresponds to a liquid port and a gas port, and a common gas port is set between two adjacent sub-active areas 111. The common gas port is simultaneously connected to the gas flow channels of the two adjacent sub-active areas 111. By locally merging the gas ports, the number of gas ports of the plate body 100 is changed from the previous 4N to 2N+2, further improving the utilization rate of the active area of ​​the plate and reducing the number of gas ports. For plates with large active areas, it is beneficial to gas distribution and ensures the uniformity of the plates. While ensuring the uniformity of fuel cells with large active areas, the present invention also effectively improves the utilization rate of the active area of ​​the plate and increases the volume power density.

[0027] like Figure 1 and 3 As shown, the present invention is a longitudinal N-connected solution. It can be understood that N plates are longitudinally connected in parallel as a single plate solution. On the basis of the single plate design solution, the larger the N (N=3, 4, 5.....) longitudinal connection solution N, the greater the active area utilization rate, wherein the active area size: the original single plate solution is a (original solution active area length) * b (original solution active area width), the longitudinal N-connected solution is a*Nb, the original single plate solution is L (original solution outer length) * K (original solution outer width), and the outer size of the N-connected solution is less than L*N*K.

[0028] like Figure 2 As shown, the two main pipe orifice areas include a first main pipe orifice area 120 and a second main pipe orifice area 130. The liquid inlet in the first main pipe orifice area 120 is a coolant inlet 121, and the liquid inlet in the second main pipe orifice area 130 is a coolant outlet 131. The center positions of the two lateral ends of each sub-active area 111 are respectively provided with a coolant inlet 121 and a coolant outlet 131.

[0029] In the first manifold port area 120, the two air ports adjacent to the coolant inlet 121 are the air inlet 122 and the hydrogen outlet 123, respectively. In the second manifold port area 130, the two air ports adjacent to the coolant outlet 131 are the hydrogen inlet 132 and the air outlet 133, respectively.

[0030] It can be understood that, in the first main pipe port area 120, the gas inlets located at the two longitudinal ends of the first main pipe port area 120 are respectively the air inlet 122 and the hydrogen outlet 123, which are separate inlets and outlets, and the other gas inlets are all shared gas inlets, that is, the shared air inlet 124 and the shared hydrogen outlet 125; in the second main pipe port area 130, the gas inlets located at the two longitudinal ends of the first main pipe port area 120 are respectively the hydrogen inlet 132 and the air outlet 133, which are separate inlets and outlets, and the other gas inlets are all shared gas inlets, that is, the shared air outlet 134 and the shared hydrogen inlet 135.

[0031] Among them, the common air inlet 124, the common hydrogen outlet 125, the common air outlet 134 and the common hydrogen inlet 135 correspond to the three adjacent sub-active areas 111 at the same time. Together with the two air inlets 122 and the two hydrogen outlets 123 at the two ends, this embodiment has 2*N+2 air inlets. Compared with the traditional 4*N air inlets, 2*N-2 air inlets are reduced, thereby reducing the sealing and frame area, and relatively reducing consumables.

[0032] Furthermore, the air inlet 122 and the hydrogen inlet 132 are disposed opposite to each other in the transverse direction, and the hydrogen outlet 123 and the air outlet 133 are disposed opposite to each other in the transverse direction.

[0033] In this embodiment, the positions of the air inlet 122 and the air outlet 133 are arranged in a centrally symmetrical manner with respect to the center of the total active area 110, the positions of the hydrogen outlet 123 and the hydrogen inlet 132 are arranged in a centrally symmetrical manner with respect to the center of the total active area 110, and the positions of the coolant inlet 121 and the coolant outlet 131 are arranged in a centrally symmetrical manner with respect to the center of the sub-active area 111, so as to improve the uniformity of the force applied to the electrode body 100 and facilitate processing and assembly.

[0034] In some other embodiments, the positions of the gas inlets and the liquid inlets on the first manifold port area 120 and the second manifold port area 130 may be relatively swapped.

[0035] Furthermore, in this embodiment, the areas of all common gas ports are larger than the areas of the ports located at the longitudinal ends of the main port region. During use, the common gas ports correspond to the gas flow channels in the two sub-active regions 111, thereby increasing the common gas port flow area and ensuring the uniformity of the plates. Specifically, the areas of the common air inlet 124 and the common hydrogen outlet 125 are larger than the air inlet 122 and hydrogen outlet 123 at the two ends, while the areas of the common air outlet 134 and the common hydrogen inlet 135 are larger than the hydrogen inlet 132 and air outlet 133 at the two ends.

[0036] In some other embodiments, the air inlet 122 is smaller than the area of ​​the air outlet 133, and the common air inlet 124 is smaller than the area of ​​the common air outlet 134, the area of ​​the common air inlet 124 is twice the area of ​​the air inlet 122, and the area of ​​the common air outlet 134 is twice the area of ​​the air outlet 133.

[0037] In some other embodiments, the area of ​​the hydrogen outlet 123 is larger than the area of ​​the hydrogen inlet 132, the area of ​​the shared hydrogen outlet 125 is larger than the area of ​​the shared hydrogen inlet 135, the area of ​​the shared hydrogen outlet 125 is twice the area of ​​the hydrogen outlet 123, and the area of ​​the shared hydrogen inlet 135 is twice the area of ​​the hydrogen inlet 132.

[0038] The electrode plate body 100 of this embodiment is formed by integral stamping, and N sub-active regions 111 , 2N+2 gas ports, and 2N liquid ports are stamped out in a single step, thereby improving electrode plate production efficiency.

[0039] like Figure 4 The example is a plate with N=3 connected in parallel vertically to form a single plate (hereinafter referred to as the vertical triple solution). The diagram shows the optimization process of removing some of the long side seals and frame areas ( Figure 4 As shown in the dotted box on the left), the gas ports of the longitudinal triple solution are 2*N+2=8 and the liquid ports are 2*N=6. The plate area size of the longitudinal triple solution is less than L*3*K, and the active area size is a*3b. Then the active area utilization rate η=(a*3b) / S 极板面积尺寸 , S 极板面积尺寸 It is smaller than the original three-plate solution, which increases the utilization rate of the active area.

[0040] like Figure 5 The figure shows the air side flow diagram of the longitudinal triple scheme. The two-inlet and two-outlet flow meets the flow requirements of the three plates of the original scheme. The hydrogen side flow is similar to the air side flow, which is also two-inlet and two-outlet, while the coolant side flow is three-inlet and three-outlet.

[0041] In addition, the present invention also proposes a fuel cell stack, comprising a plurality of longitudinal multi-connected plates, which are stacked in sequence, and a proton membrane group is provided between two adjacent plate bodies 100. Under the premise of certain power demand, the stacking of longitudinal N-connected plates can effectively reduce the number of stacked plates and improve the volume power density.

[0042] Compared with the original solution, the advantages of this embodiment are: the active area utilization rate is significantly improved. The active area utilization rate of the original solution is generally around 45% to 50%, while the longitudinal N-connected solution can increase the active area utilization rate to 55%-65% (fluctuating according to the local design of the plate); the stack core size can be reduced, and the volume power density of the stack can be improved under certain power requirements; it can be used as an optimization direction for stack weight reduction to improve the mass power density of the stack; the longitudinal N-connected solution can realize the overall stamping of the plate, and N sub-active areas 111 can be stamped in a single time, thereby improving the plate production efficiency; the stack stacking efficiency is improved, and the stack production cycle is improved: under certain power requirements, the longitudinal N-connected solution can shorten the original stacking time to 1 / N of the original time; multiple gas ports are shared, which is conducive to gas distribution, so for active plates with large active areas, the distribution uniformity of this solution is better than that of the original solution.

[0043] Throughout this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of these terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

[0044] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A longitudinal multi-electrode plate, characterized in that: include: A plate body, the plate body comprising a total active area extending longitudinally, and two main pipe port areas located on two longitudinal sides of the total active area, the total active area comprising N sub-active areas sequentially connected in the longitudinal direction, wherein N is greater than or equal to 3, and the main pipe port areas comprising gas ports and liquid ports alternately arranged in the longitudinal direction; In each of the main pipe port areas, the number of the gas ports is N+1, the number of the liquid ports is N, there is one liquid port between each adjacent gas port, the gas port between the two adjacent liquid ports is set as a common gas port, the common gas port is located between the two adjacent sub-active areas, the common gas port is simultaneously connected to the gas flow channels of the two sub-active areas, and the liquid port is connected to the cooling liquid flow channels of the sub-active areas in a one-to-one correspondence.

2. The longitudinal multi-electrode plate according to claim 1, characterized in that: The area of ​​the common air port is larger than the area of ​​the air ports located at both ends of the main pipe port area in the longitudinal direction.

3. The longitudinal multi-electrode plate according to claim 1, characterized in that: The two main pipe orifice areas include a first main pipe orifice area and a second main pipe orifice area. The liquid inlet in the first main pipe orifice area is a cooling liquid inlet, and the liquid inlet in the second main pipe orifice area is a cooling liquid outlet. The cooling liquid inlet and the cooling liquid outlet are respectively provided at the center position of the two lateral ends of each sub-active area.

4. The longitudinal multi-electrode plate according to claim 3, characterized in that: In the first manifold port area, the two gas ports arranged adjacent to the coolant inlet are respectively an air inlet and a hydrogen outlet; In the second manifold port area, the two gas ports adjacent to the coolant outlet are a hydrogen inlet and an air outlet respectively.

5. The longitudinal multi-electrode plate according to claim 4, characterized in that: The air inlet and the hydrogen inlet are arranged opposite to each other in the transverse direction, and the hydrogen outlet and the air outlet are arranged opposite to each other in the transverse direction.

6. The longitudinal multi-electrode plate according to claim 5, characterized in that: The positions of the air inlet and the air outlet are centrally symmetrically arranged with respect to the center of the total active area.

7. The longitudinal multi-electrode plate according to claim 5, characterized in that: The hydrogen outlet and the hydrogen inlet are arranged in a centrally symmetrical manner with respect to the center of the total active area.

8. The longitudinal multi-electrode plate according to claim 5, characterized in that: The coolant inlet and the coolant outlet are arranged in a centrally symmetrical manner with respect to the center of the sub-active area.

9. The longitudinal multi-electrode plate according to claim 1, characterized in that: The pole plate body is formed by integral stamping.

10. A fuel cell stack, characterized in that: It comprises a plurality of longitudinal multi-connected plates as described in any one of claims 1 to 9, wherein the plurality of longitudinal multi-connected plates are stacked in sequence, and a proton membrane group is provided between two adjacent plate bodies.

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