New fuel cell structure

Abstract

The present invention discloses a novel battery stack structure, comprising a first end plate, a second end plate, and at least two bipolar plates of different plate types arranged between the first end plate and the second end plate, wherein a membrane electrode structure is arranged between two adjacent bipolar plates; wherein each bipolar plate is respectively provided with a first inlet, the plate type of the bipolar plate is defined by the size of the first inlet, and the sizes of the first inlets of bipolar plates of different plate types are different; a first common inlet corresponding to the position of the first inlet is arranged on the first end plate, and the first common inlet and the first inlet of the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the first inlet arranged on at least part of the bipolar plates in the formed common pipeline corresponding to the first inlet is reduced as the distance between the bipolar plate and the first end plate increases. The present invention can make the pressure difference, concentration difference and speed difference of the gas in the pipeline smaller, the gas pressure distribution more uniform, and the gas flow rate at the far end faster and the concentration higher.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a novel fuel cell stack structure. Background Art

[0002] The main principle of fuel cells is to convert chemical energy into electrical energy. The most important component inside a fuel cell cell is the membrane electrode. In actual applications, multiple cells can be combined into a fuel cell stack according to design requirements to meet the needs of different power outputs. Currently, hydrogen is the main fuel. Compared with methane or petroleum gas as raw materials, carbon deposits occur on the anode due to insufficient reaction and then adhere to the surface of the catalyst active site of the anode, accelerating the activity decline of the fuel cell. The advantage of hydrogen is that the reaction generates water vapor, which is very clean.

[0003] In the prior art, the bipolar plate structure is an indispensable structure in a fuel cell. The bipolar plate structure is provided with an inlet for passing hydrogen or oxygen into the flow channel on the bipolar plate and an outlet for discharging the hydrogen or oxygen after passing through the flow channel. When hydrogen or oxygen flows through the inlet, it will flow through the flow channel on the bipolar plate and be discharged from the outlet through the flow channel. The fuel cell is composed of a plurality of stacked bipolar plate structures and membrane electrode structures, so the inlets or outlets on the plurality of bipolar plates will form a common pipeline. By passing hydrogen or oxygen from the common pipeline corresponding to the inlet, hydrogen or oxygen will be passed into each bipolar plate, react with the membrane electrode structure, and then be discharged from the common pipeline corresponding to the outlet.

[0004] Currently, there is a problem in the use of fuel cells: since the concentration of hydrogen or oxygen in the gas is fixed when the gas is introduced into the common pipeline corresponding to the inlet, when the gas passes through the common pipeline, the concentration of hydrogen or oxygen when passing through the inlet close to the common pipeline will be much higher than the concentration of hydrogen or oxygen when passing through the inlet far away from the common pipeline. Therefore, in the fuel cell, the membrane electrode structure far away from the common pipeline will have incomplete reaction during the reaction, affecting the overall uniformity and performance of the fuel cell, and even affecting the service life of the fuel cell. Summary of the invention

[0005] The embodiment of the present invention provides a novel fuel cell stack structure to solve the problem in the prior art that the gas volume and gas concentration far away from the inlet of the common pipeline are not high enough, which affects the uniformity and performance of the entire fuel cell.

[0006] According to one aspect of the present invention, a novel stack structure is provided, comprising a first end plate, a second end plate, and at least two bipolar plates of different plate types arranged between the first end plate and the second end plate, wherein a membrane electrode structure is arranged between two adjacent bipolar plates;

[0007] Wherein, each bipolar plate is provided with a first inlet, and the plate type of the bipolar plate is determined by the size of the first inlet. The sizes of the first inlets of bipolar plates of different plate types are different;

[0008] A first common inlet corresponding to the position of the first inlet is arranged on the first end plate, and the first common inlet and the first inlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the first inlet arranged on at least part of the bipolar plate in the common pipeline corresponding to the first inlet decreases as the distance between the bipolar plate and the first end plate increases.

[0009] The novel stack structure of the present invention designs the bipolar plate structure that constitutes it to form at least two bipolar plates with different plate types, so that the bipolar plates that constitute the novel stack structure have at least two different first inlet sizes, so that the common channel corresponding to the first inlet formed by these bipolar plates can form a structural style in which the first inlet on at least part of the bipolar plate structure is set to be reduced as the distance from the first end plate provided with the first common inlet increases. Therefore, when the gas is passed into the common pipeline corresponding to the first inlet, when the gas is passed to the part of the common pipeline that is relatively far from the inlet of the common pipeline, due to the reduction of the diameter of the common pipeline, the pressure difference, concentration difference and speed difference of the gas in the pipeline are smaller, the gas pressure distribution is more uniform, and the gas flow rate at the far end is faster and the concentration is higher, so as to ensure that the membrane electrode structure far away from the common pipeline can react more completely, improve the uniformity and performance of the overall fuel cell, and improve the service life of the overall fuel cell.

[0010] In some embodiments, the size of the first inlet disposed on the bipolar plate in the common conduit formed corresponding to the first inlet is negatively correlated to the size of the distance between the bipolar plate and the first end plate.

[0011] Therefore, through such an arrangement, the common pipeline corresponding to the first inlet formed by the overall novel stack structure of the present invention can have a gradual diameter, so that the diameter of the common pipeline gradually decreases as it moves away from the first end plate, so as to increase the concentration of hydrogen or oxygen when the gas enters the part away from the common pipeline, thereby ensuring that the membrane electrode structure away from the common pipeline can react more completely.

[0012] In some embodiments, the bipolar plates sequentially arranged between the first end plate and the second end plate are divided into at least two first bipolar plate groups according to the distance between them and the first end plate, the first inlets of the bipolar plates in each first bipolar plate group are of the same size, and at least part of the first bipolar plate groups in the common pipeline corresponding to the first inlet are arranged in the order of decreasing the size of the first inlet arranged on the bipolar plate as the distance between them and the first end plate increases.

[0013] Therefore, by such an arrangement, the bipolar plates can be grouped so as to utilize the grouping design so that at least a portion of the common pipeline is changed from a structural design that gradually shrinks as the distance from the first end plate increases to a structural design that gradually shrinks as the distance from the first end plate increases, so that the sizes of the first inlets on multiple bipolar plates can be designed to be the same, which reduces the design difficulty and manufacturing difficulty of the overall stack structure and can also increase the concentration of hydrogen or oxygen when the gas is passed into the portion away from the common pipeline.

[0014] In some embodiments, the common conduits formed corresponding to the first inlets in each group of first bipolar plate groups are arranged in the order of decreasing sizes of the first inlets provided on the bipolar plates as the distance from the first end plate increases.

[0015] Therefore, by such an arrangement, it can be ensured that the gradient of the entire common pipeline can decrease as the distance from the first end plate increases, so as to increase the concentration of hydrogen or oxygen when the gas enters the part away from the common pipeline.

[0016] In some embodiments, the bipolar plate is further provided with a first outlet, and the bipolar plate arranged between the first end plate and the second end plate has at least two different first outlet plate types, the first outlet plate type is defined by the size of the first outlet, and the sizes of the first outlets on different first outlet plate types are different. The first end plate is also provided with a first common outlet corresponding to the position of the first outlet, and the first common outlet and the first outlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the first outlet arranged on at least part of the bipolar plates in the common pipeline corresponding to the first outlet is reduced as the distance between the bipolar plate and the first end plate is reduced.

[0017] Therefore, by such an arrangement, at least a portion of the common pipeline corresponding to the first outlet on the stack structure can form a structural design that decreases as the distance from the first end plate decreases, thereby increasing the flow rate of the gas during discharge.

[0018] In some embodiments, the size of the first outlet disposed on the bipolar plate in the common conduit formed corresponding to the first outlet is positively correlated with the size of the distance between the bipolar plate and the first end plate.

[0019] Therefore, through such an arrangement, the entire common pipeline corresponding to the outlet on the stack structure can form a structural design that decreases as the distance from the first end plate decreases, thereby increasing the flow rate of the gas during discharge.

[0020] In some embodiments, the bipolar plates sequentially arranged between the first end plate and the second end plate are divided into at least two second bipolar plate groups according to the distance between them and the first end plate, the first outlets of the bipolar plates in each second bipolar plate group are the same in size, and at least a portion of the second bipolar plate groups in the common pipeline corresponding to the first outlet are arranged in the order of decreasing size of the first outlet arranged on the bipolar plates as the distance between them and the first end plate decreases.

[0021] Therefore, by such an arrangement, the bipolar plates can be grouped, and the grouping design can be used to change the structural design in which at least part of the common pipeline gradually shrinks as the distance from the first end plate decreases to a structural design in which the gradient decreases as the distance from the first end plate decreases, so that the sizes of the first outlets on multiple bipolar plates can be designed to be the same, thereby reducing the design difficulty and manufacturing difficulty of the overall stack structure and ensuring the effect of increasing the flow rate of gas discharge.

[0022] In some embodiments, the common conduits of the first outlets formed between each group of second bipolar plate groups are arranged in the order of decreasing size as the distance from the first end plate decreases according to the size of the first outlets provided on the bipolar plates.

[0023] Therefore, by such an arrangement, it can be ensured that the entire common pipeline can be reduced in gradient as the distance from the first end plate decreases, so as to achieve the effect of increasing the flow rate of gas during discharge.

[0024] In some embodiments, the bipolar plate is further provided with a second inlet, and the bipolar plate arranged between the first end plate and the second end plate has at least two different second inlet plate types, the second inlet plate type is defined by the size of the second inlet, and the sizes of the second inlets on different second inlet plate types are different, and a second common inlet corresponding to the position of the second inlet is provided on the first end plate, and the second common inlet and the second inlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the second inlet arranged on at least part of the bipolar plates in the formed common pipeline corresponding to the second inlet decreases as the distance between the bipolar plate and the first end plate increases.

[0025] Therefore, through such an arrangement, the hydrogen inlet and the oxygen inlet on the overall stack structure can be set to a structural design that decreases as the distance between the bipolar plate and the first end plate increases, so as to simultaneously increase the concentration of hydrogen and oxygen when they are introduced into the part away from the common pipeline.

[0026] In some embodiments, the bipolar plate is further provided with a second outlet, and the bipolar plate arranged between the first end plate and the second end plate has at least two different second outlet plate types, the second outlet plate type is defined by the size of the second outlet, and the sizes of the second outlets on different second outlet plate types are different. The first end plate is also provided with a second common outlet corresponding to the position of the second outlet, and the second common outlet and the second outlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the second outlet arranged on at least part of the bipolar plates in the common pipeline corresponding to the second outlet decreases as the distance between the bipolar plate and the first end plate decreases.

[0027] Therefore, by such an arrangement, the gas discharge speed in the hydrogen outlet and the oxygen outlet on the overall stack structure can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0029] Figure 1 This is a schematic diagram of a common pipeline structure corresponding to an inlet of a novel battery stack structure according to an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of a common pipeline structure corresponding to an inlet of a novel battery stack structure according to another embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of a common pipeline structure corresponding to an inlet of a novel battery stack structure according to another embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of a common pipeline structure corresponding to an outlet of a novel battery stack structure according to an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of a common pipeline structure corresponding to an outlet of a novel battery stack structure according to another embodiment of the present invention;

[0034] Figure 6 This is a schematic diagram of a common pipeline structure corresponding to an outlet of a novel battery stack structure according to another embodiment of the present invention;

[0035] Figure numerals: 1. first end plate; 11. first common inlet; 12. first common outlet; 13. second common inlet; 14. second common outlet; 2. second end plate; 3. bipolar plate; 31. first inlet; 311. first bipolar plate group; 32. first outlet; 321. second bipolar plate group; 33. second inlet; 34. second outlet; 4. common pipeline. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0038] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include" and "comprise" include not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such processes, methods, articles or equipment. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, method, article or equipment that includes the elements.

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0040] Regarding the problem that when the fuel cell in the prior art is working, the membrane electrode far away from the entrance of the common pipeline is prone to incomplete reaction and affects the overall performance of the fuel cell. After research, it is found that the main reason is that in the prior art, since a large number of bipolar plate structures and membrane electrode structures need to be stacked in the fuel cell, the bipolar plate structure is generally completely the same structure to reduce the cost and difficulty of production, and also to ensure that the composed fuel cell can form a non-physical common pipeline that allows gas to pass smoothly when working. Therefore, the present invention designs the structure of the gas inlet on the bipolar plate structure that constitutes the fuel cell, thereby realizing the modification of the diameter of the non-physical common pipeline, and then achieving the change of the concentration of hydrogen or oxygen when the gas flows into the flow channel of the bipolar plate through the common pipeline.

[0041] Figure 1 The overall structure diagram of the novel battery stack structure according to one embodiment of the present invention is schematically shown. Figure 1 As shown, the novel stack structure of the present invention includes a first end plate 1, a second end plate 2, and at least two bipolar plates 3 of different plate types arranged between the first end plate 1 and the second end plate 2, wherein a membrane electrode structure is arranged between two adjacent bipolar plates 3 to form a stacking structure of bipolar plate 3-membrane electrode structure-bipolar plate 3, and an overall stack structure is formed under the clamping of the first end plate 1 and the second end plate 2. In the stack structure, a first inlet 31 is arranged on each bipolar plate 3, and the first inlet 31 can be an inlet for introducing oxygen or an inlet for introducing hydrogen. The first inlets 31 on the stacked bipolar plates 3 are aligned to form a common pipeline 4 corresponding to the first inlet 31, and a first common inlet 11 is arranged on the first end plate 1, and the first inlet 31 on the bipolar plate 3 is arranged at a position corresponding to the position of the first common inlet 11, so that the first common inlet 11 forms the inlet of the common pipeline 4. Among the multiple bipolar plates 3 stacked, the plate type of the bipolar plates 3 is defined by the size of the first inlet 31. The sizes of the first inlet 31 of the bipolar plates 3 of different plate types are different, so that the size of the first inlet 31 set on at least part of the bipolar plates 3 in the common pipeline 4 corresponding to the first inlet 31 is reduced as the distance between the bipolar plate 3 and the first end plate 1 increases. In this design, the diameter of the common pipeline 4 at the position of the common pipeline 4 corresponding to the bipolar plates 3 with different sizes of the first inlet 31 will form a trend of reducing as the distance from the first end plate 1 increases. By reducing the diameter of the pipe, the amount of other gases such as hydrogen or oxygen is reduced, thereby increasing the concentration of hydrogen or oxygen at this section, alleviating the problem in the prior art that the membrane electrode is prone to incomplete reaction due to the low concentration of hydrogen or oxygen at the inlet position far from the common pipeline 4, thereby affecting the uniformity and performance of the fuel cell as a whole.

[0042] In the technical solution of the present invention, it can be understood that among the several bipolar plates 3 constituting the common pipeline 4 corresponding to the first inlet 31, at least part of the bipolar plates 3 are arranged to be reduced as the distance between the bipolar plates 3 and the first end plate 1 increases, so that the concentration of hydrogen or oxygen in the corresponding part of the common pipeline 4 can be increased. Figure 2As shown, as a preferred embodiment, all the bipolar plates 3 used to form the common pipeline 4 corresponding to the first inlet 31 can be set so that the size of the first inlet 31 set on the bipolar plate 3 is negatively correlated with the size of the distance between the bipolar plate 3 and the first end plate 1, that is, the size of the first inlet 31 on each bipolar plate 3 decreases as the distance between the bipolar plate 3 and the first end plate 1 increases, so that the entire common pipeline 4 formed can be a structure that gradually shrinks as the distance from the first end plate 1 increases, so that when the gas enters the common pipeline 4, the concentration of hydrogen or oxygen in the gas introduced can be automatically adjusted as the depth of the gas introduced into the common pipeline 4, thereby ensuring that the membrane electrode structure that is far away from the inlet of the common pipeline 4 can also react completely, thereby ensuring the performance of the overall stack during operation.

[0043] The implementation method in which the size of the first inlet 31 on each bipolar plate 3 decreases as the distance between the bipolar plate 3 and the first end plate 1 increases should be the most effective implementation method in theory. However, in practical applications, this design method requires a special structural design for each bipolar plate 3, and the structural differences between each bipolar plate 3 are small, so the processing accuracy needs to be very high. Therefore, from the perspective of cost and processing difficulty, this design method is difficult to implement. Therefore, the present invention has made further optimizations on this basis. For details, please refer to Figure 3 As shown, in Figure 3In the illustrated embodiment, the bipolar plates 3 sequentially arranged between the first end plate 1 and the second end plate 2 are divided into at least two groups of first bipolar plate groups 311 according to the distance between the first end plate 1. In each group of the first bipolar plate groups 311, the sizes of the first inlets 31 arranged on the bipolar plates 3 are the same, while in different groups of the first bipolar plate groups 311, the sizes of the first inlets 31 on the bipolar plates 3 of the two groups are different. At this time, when these first bipolar plate groups 311 are arranged, at least part of the first bipolar plate groups 311 in the common pipeline 4 of the first inlet 31 formed are arranged in the order of decreasing as the distance from the first end plate 1 increases according to the size of the first inlet 31 arranged on the bipolar plates 3. It can be understood that the first bipolar plate groups 311 arranged in the order of decreasing as the distance from the first end plate 1 increases according to the size of the first inlet 31 arranged on the bipolar plates 3 are preferably arranged so that each group of the first bipolar plate groups 311 is designed in this way. Exemplarily, taking a fuel cell provided with 300 groups of bipolar plates 3 as an example, the area size of the first inlet 31 in the first 100 groups of bipolar plates 3 close to the first end plate 1 can be designed to be 1.2 times the original design area of ​​the first inlet 31, the area size of the first inlet 31 in the middle 100 groups of bipolar plates 3 can be designed to be the original design area of ​​the first inlet 31, and the area size of the first inlet 31 in the 100 groups of bipolar plates 3 farthest from the first end plate 1 can be designed to be 0.8 times the original design area of ​​the first inlet 31, so that the formed common pipeline 4 has a gradient indentation design structure. The design of this embodiment can group the bipolar plates 3 so that at least a portion or the entire section of the common pipe 4 can be changed from a structural design that gradually shrinks as the distance from the first end plate 1 increases to a structural design that gradually shrinks as the distance from the first end plate 1 increases. This allows the sizes of the first inlets 31 on multiple bipolar plates 3 to be designed to be the same, thereby reducing the design and manufacturing difficulties of the overall stack structure. At the same time, it can also ensure that the concentration of hydrogen or oxygen is increased when the gas is introduced into the portion away from the common pipe 4.

[0044] As a possible implementation, in the novel stack structure of the present invention, in addition to designing the structure of the first inlet 31 on each bipolar plate 3 of the common pipeline 4 corresponding to the inlet of the composition gas, the structure of the first outlet 32 ​​on each bipolar plate 3 of the common pipeline 4 corresponding to the outlet of the composition gas can also be designed. Figure 4 As shown, in Figure 4In the embodiment shown, the first end plate 1 is further provided with a first common outlet 12, and the bipolar plate 3 provided between the first end plate 1 and the second end plate 2 has at least two different first outlet plate types, and the sizes of the first outlets 32 on the bipolar plates 3 corresponding to the different first outlet plate types are different. The first end plate 1 is further provided with a first common outlet 12, and the position of the first common outlet 12 corresponds to the first outlet 32 ​​provided on each bipolar plate 3. The first outlet 32 ​​of the common pipeline 4 constituting the outlet of the gas, and the size of the first outlet 32 ​​provided on at least part of the bipolar plates 3 in the common pipeline 4 corresponding to the first outlet 32 ​​will be reduced as the distance between the bipolar plate 3 and the first end plate 1 is reduced. In this way, when the gas enters the bipolar plate 3 from the common pipeline 4 corresponding to the inlet, flows through the flow channel on the bipolar plate 3 to react with the membrane electrode structure, and is discharged from the first outlet 32, it will be discharged from the common pipeline 4 composed of the first outlet 32. The flow direction of the gas during discharge is toward the first end plate 1, and the size of the first outlet 32 ​​set on at least part of the bipolar plate 3 will be reduced as the distance between the bipolar plate 3 and the first end plate 1 decreases, which will cause at least part of the common pipe 4 corresponding to the outlet to gradually shrink along the flow direction of the gas. The common pipe 4 with a gradually shrinking diameter will increase the flow rate of the gas, thereby increasing the speed of the gas during discharge. By increasing the flow rate of the discharged gas, the discharge of water generated by the reaction of the battery stack during operation can be accelerated to avoid water accumulation.

[0045] As a preferred embodiment, all the bipolar plates 3 used to form the common pipeline 4 can be set so that the size of the first outlet 32 ​​set on the bipolar plate 3 is positively correlated with the size of the distance between the bipolar plate 3 and the first end plate 1, that is, the size of the first outlet 32 ​​set on each bipolar plate 3 decreases as the distance between the bipolar plate 3 and the first end plate 1 decreases, so that the entire common pipeline 4 formed can be a structure that gradually decreases as the distance between the bipolar plate 3 and the first end plate 1 decreases, so that the flow rate of the gas when it is discharged from the common pipeline 4 will gradually increase, thereby achieving rapid discharge of the gas. Specifically, refer to Figure 5 As stated, Figure 5 In the above-described embodiment, Figure 2 Similar to the above-mentioned embodiment, the first outlets 32 on all the bipolar plates 3 constituting the common pipeline 4 are also configured such that the sizes thereof decrease as the distance between the bipolar plates 3 and the first end plate 1 decreases.

[0046] Similarly, the first outlet 32 ​​is configured such that its size decreases as the distance between the bipolar plate 3 and the first end plate 1 decreases. This is theoretically the best implementation. However, in practical applications, its processing cost and difficulty are very high. Therefore, the present invention is further optimized on this basis. Figure 6 As shown, Figure 6 In the embodiment shown, Figure 3 Similar to the embodiment shown, the bipolar plates 3 sequentially arranged between the first end plate 1 and the second end plate 2 are also divided into at least two groups of second bipolar plate groups 321 according to the distance between the first end plate 1, and the sizes of the first outlets 32 set on the bipolar plates 3 in each group of second bipolar plate groups 321 are the same, and the sizes of the first outlets 32 set on the bipolar plates 3 between different second bipolar plate groups 321 are different, and at least part of the second bipolar plate groups 321 in the common pipeline 4 corresponding to the second outlets 32 are arranged in a sequence of decreasing with the decrease of the distance from the first end plate 1 according to the size of the first outlets 32 set on the bipolar plates 3. It can be understood that the first bipolar plate group 311 arranged in a sequence of decreasing with the decrease of the distance from the first end plate 1 according to the size of the first outlets 32 set on the bipolar plates 3 is preferably set to be designed in this way for each group of second bipolar plate groups 321. The design of this embodiment can group the bipolar plates 3 so that at least a portion or the entire section of the common pipeline 4 can be changed from a structural design that gradually shrinks as the distance from the first end plate 1 decreases to a structural design that gradually shrinks as the distance from the first end plate 1 decreases. This allows the sizes of the first outlets 32 on multiple bipolar plates 3 to be designed to be the same, thereby reducing the design difficulty and manufacturing difficulty of the overall stack structure, while also ensuring the effect of increasing the gas discharge speed.

[0047] At the same time, in the above-mentioned embodiment, the common pipe 4 corresponding to the inlet can also be set to be divided into multiple groups of first bipolar plate groups 311. The two embodiments can be combined to improve the performance of the overall stack structure. At this time, when the bipolar plates 3 between the first end plate 1 and the second end plate 2 are divided into multiple groups of first bipolar plate groups 311 and multiple groups of second bipolar plate groups 321, the bipolar plates 3 in the multiple groups of first bipolar plate groups 311 can be different from the bipolar plates 3 in the multiple groups of second bipolar plate groups 321, that is, a certain bipolar plate 3 may be in the first group of first bipolar plate groups 311 and in the second group of second bipolar plate groups 321. The specific division of the first bipolar plate group 311 and the second bipolar plate group 321 can be designed according to actual needs. As a preferred embodiment, the bipolar plates 3 included in each group of first bipolar plate groups 311 and each group of second bipolar plate groups 321 can be designed to be the same, that is, the second bipolar plate groups 321 are divided according to the rules for dividing the first bipolar plate groups 311, or the first bipolar plate groups 311 are divided according to the rules for dividing the second bipolar plate groups 321. This design can reduce the number of bipolar plate 3 structural types during the design and production of the bipolar plates 3, thereby reducing the production difficulty and production cost.

[0048] For the formed battery stack structure, it can be understood that it generally has two common pipes 4 corresponding to the gas inlets, and two common pipes 4 corresponding to the gas outlets. Take the common pipe 4 corresponding to another gas inlet, whose inlet on the first end plate 1 is the second common inlet 13, and whose inlet on the bipolar plate 3 is the second inlet 33, and the common pipe 4 corresponding to another gas outlet, whose outlet on the first end plate 1 is the second common outlet 14, and whose outlet on the bipolar plate 3 is the second outlet 34 as an example, referring to Figures 1 to 6 As shown, the size of the second inlet 33 provided on the bipolar plate 3 in the common conduit 4 corresponding to the second inlet 33 can also be set to decrease as the distance between the bipolar plate 3 and the first end plate 1 increases, and the size of the second outlet 34 provided on the bipolar plate 3 in the common conduit 4 corresponding to the second outlet 34 can also be set to decrease as the distance between the bipolar plate 3 and the first end plate 1 decreases. In addition, the second inlet 33 can also be set to a structure that decreases gradually as the distance between the bipolar plate 3 and the first end plate 1 increases, and the second outlet 34 can also be set to a structure that decreases gradually as the distance between the bipolar plate 3 and the first end plate 1 decreases. The specific setting method can refer to the relevant description of the first inlet 31 and the first outlet 32 ​​in the previous text, which will not be repeated here.

[0049] The novel stack structure of the present invention designs the bipolar plate 3 structure that constitutes it, and sets the first inlet 31 on the bipolar plate 3 structure to decrease as the distance from the first end plate 1 provided with the first common inlet 11 increases, so that the diameter of the common pipe 4 corresponding to the inlet formed in the stack structure will gradually decrease as it moves away from the first end plate 1. When the gas is passed into the common pipe 4 corresponding to the inlet, when the gas passes to the part of the common pipe 4 that is farther away from its inlet, due to the reduction in the diameter of the common pipe 4, even if the content of hydrogen or oxygen in the gas is relatively low, the content of other gases will also be reduced, so that the concentration of hydrogen or oxygen in the gas can be improved relative to the structure of the prior art, so as to ensure that the membrane electrode structure far away from the common pipe 4 can react more completely, improve the performance of the overall fuel cell, and increase the service life of the overall fuel cell.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery stack structure, characterized in that: It includes a first end plate, a second end plate, and at least two bipolar plates of different plate types arranged between the first end plate and the second end plate, and a membrane electrode structure is arranged between two adjacent bipolar plates; Wherein, each bipolar plate is provided with a first inlet, and the shape of the bipolar plate is determined by the size of the first inlet. The sizes of the first inlets of bipolar plates of different plate shapes are different; The first end plate is provided with a first common inlet corresponding to the position of the first inlet, the first common inlet and the first inlet on the bipolar plate provided between the first end plate and the second end plate form a common pipeline, the bipolar plates arranged in sequence between the first end plate and the second end plate are divided into at least two groups of first bipolar plate groups according to the distance between them and the first end plate, the first inlets of the bipolar plates in each group of first bipolar plate groups are of the same size, and the first bipolar plate groups in the common pipeline corresponding to the first inlet are arranged in the order of decreasing the size of the first inlets provided on the bipolar plates as the distance between them and the first end plate increases; The bipolar plate is also provided with a first outlet, and the bipolar plate arranged between the first end plate and the second end plate has at least two different first outlet plate types, the first outlet plate type is defined by the size of the first outlet, and the sizes of the first outlets on different first outlet plate types are different. The first end plate is also provided with a first common outlet corresponding to the position of the first outlet, and the first common outlet and the first outlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the bipolar plates arranged in sequence between the first end plate and the second end plate are divided into at least two groups of second bipolar plate groups according to the distance between the first end plate, and the first outlets of the bipolar plates in each group of second bipolar plate groups are the same in size, and the second bipolar plate groups in the common pipeline corresponding to the first outlet are arranged in the order of decreasing as the size of the first outlets arranged on the bipolar plates decreases with the decrease of the distance between the first end plate; The bipolar plate is also provided with a second inlet, and the bipolar plate disposed between the first end plate and the second end plate has at least two different second inlet plate types, the second inlet plate type is defined by the size of the second inlet, and the sizes of the second inlets on different second inlet plate types are different, the first end plate is provided with a second common inlet corresponding to the position of the second inlet, the second common inlet and the second inlet on the bipolar plate disposed between the first end plate and the second end plate form a common pipeline, and the size of the second inlet disposed on the bipolar plate in the formed common pipeline corresponding to the second inlet is reduced as the distance between the bipolar plate and the first end plate increases; The bipolar plate is also provided with a second outlet, and the bipolar plate arranged between the first end plate and the second end plate has at least two different second outlet plate types, the second outlet plate type is defined by the size of the second outlet, and the sizes of the second outlets on different second outlet plate types are different. The first end plate is also provided with a second common outlet corresponding to the position of the second outlet, and the second common outlet and the second outlet on the bipolar plate arranged between the first end plate and the second end plate form a common pipeline, and the size of the second outlet arranged on the bipolar plate in the common pipeline corresponding to the second outlet is reduced as the distance between the bipolar plate and the first end plate is reduced.

2. The battery stack structure according to claim 1, characterized in that: The first bipolar plate groups in each group of the common conduits corresponding to the first inlets are arranged in the order of decreasing with increasing distance from the first end plate according to the size of the first inlets arranged on the bipolar plates.

3. The battery stack structure according to claim 1, characterized in that: The second bipolar plate groups in each group of the common conduits corresponding to the first outlets are arranged in the order of decreasing size as the distance from the first end plate decreases according to the size of the first outlets arranged on the bipolar plates.

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