Fuel cell sealing polar plate, preparation method and fuel cell

Abstract

The invention provides a fuel cell sealing polar plate, a preparation method and a fuel cell. The fuel cell sealing polar plate comprises a fuel cell polar plate, a sealing gasket and an adhesive limiting body, a sealing groove and a first limiting groove are formed in the fuel cell polar plate; the first limiting groove is formed below the sealing groove and is communicated with the sealing groove; the sealing gasket is arranged in the sealing groove, a second limiting groove aligned with the first limiting groove is formed in the surface, close to the groove bottom wall of the sealing groove, of the sealing gasket, and the first limiting groove and the second limiting groove are filled with the adhesive limiting body. Through the bonding and limiting effects of the adhesive limiting body, the sealing gasket is not prone to lateral displacement even if the sealing gasket operates in a high-pressure gas environment, and the sealing reliability is good. And the sealing gasket and the sealing groove are difficult to separate, so that the sealing durability is better.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell sealing plate, a preparation method and a fuel cell. Background Art

[0002] A fuel cell is a device that uses fuel and oxidant to directly convert chemical energy into electrical energy. Proton exchange membrane fuel cell (PEMFC) is a common type of fuel cell, which has the advantages of low operating temperature, fast startup, high specific power, simple structure, and easy operation. It has great application potential in new energy vehicles, fixed power stations, aviation, ships, etc.

[0003] Proton exchange membrane fuel cells usually use a gas such as hydrogen as a fuel and a gas such as air or oxygen as an oxidant. Proton exchange membrane fuel cells usually include bipolar plates, membrane electrodes, current collecting plates, end plates, seals and fasteners. Sealing performance is one of the most important factors to ensure the reliability and safety of fuel cells. In some confined spaces, such as aviation and underwater applications, fuel cells have high requirements for sealing to ensure that the fuel cell does not flow through the sealing parts to the outside of the fuel cell, causing the hydrogen concentration in the confined space to be too high, so as to ensure the reliability and safety of the fuel cell.

[0004] Traditional fuel cells usually have a sealing gasket structure arranged in the sealing groove, and the sealing gasket abuts or adheres to the bottom of the sealing groove to achieve sealing. This sealing method has at least the following disadvantages: before the glue cures and after the sealing gasket is attached to the sealing groove, it is easy to shift, resulting in a micro gas channel between the sealing gasket and the sealing groove, that is, the sealing effect is poor, and the high-pressure gas is easy to leak gradually. In addition, after the sealing gasket has been running for a long time in a high-temperature, high-pressure, acidic and oxidizing working environment, the sealing gasket is easy to separate from the sealing groove, causing the sealing gasket to fall off, affecting the sealing performance, that is, the sealing durability is poor. In addition, when a higher pressure gas is introduced, the sealing gasket is also prone to lateral displacement due to the pressure difference, and there is a problem of poor sealing reliability. Summary of the invention

[0005] Based on this, it is necessary to provide a fuel cell sealing plate that can improve the sealing effect, sealing durability and sealing reliability of the sealing gasket in order to address the problems in the above-mentioned background technology.

[0006] In order to solve the above technical problems, in a first aspect, the present disclosure provides a fuel cell sealing plate, which includes a fuel cell plate, a sealing gasket and an adhesive limiter;

[0007] The fuel cell plate is provided with a sealing groove and a first limiting groove, wherein the first limiting groove is provided below the sealing groove and communicated with the sealing groove;

[0008] The sealing gasket is arranged in the sealing groove, and a second limiting groove aligned with the first limiting groove is arranged on the surface of the sealing gasket close to the bottom wall of the sealing groove, and the adhesive limiting body is filled in the first limiting groove and the second limiting groove.

[0009] In some embodiments of the present disclosure, the number of the first limiting grooves is 1 to 10.

[0010] In some embodiments of the present disclosure, a plurality of the first limiting grooves are provided on the fuel cell plate, and a plurality of the second limiting grooves are correspondingly provided on the surface of the sealing gasket close to the bottom wall of the sealing groove.

[0011] In some embodiments of the present disclosure, an extension direction of each of the first limiting grooves intersects with a width direction of the sealing groove, and a plurality of the first limiting grooves are spaced apart and arranged in sequence in the width direction of the sealing groove.

[0012] In some embodiments of the present disclosure, the cross-sectional area of ​​the first limiting groove in its depth direction is 0.4 mm 2 ~5mm 2 and / or,

[0013] The cross-sectional area of ​​the second limiting groove in its depth direction is 0.4 mm 2 ~5mm 2 .

[0014] In some embodiments of the present disclosure, along the direction from the notch of the first limiting groove to the bottom wall thereof, the radial dimension of the first limiting groove gradually shrinks; or,

[0015] Along the direction from the notch of the first limiting groove toward the bottom wall thereof, the radial dimension of the first limiting groove remains unchanged.

[0016] In some embodiments of the present disclosure, the orthographic projection of the notch of the second limiting groove on the notch of the first groove coincides with the notch of the first groove.

[0017] In some embodiments of the present disclosure, the sealing gasket is a rubber sealing gasket; and / or,

[0018] The adhesive limiter is a solid structure formed after the glue is cured.

[0019] In some embodiments of the present disclosure, the adhesive limiter is further extended between the sealing gasket and the bottom wall of the sealing groove.

[0020] In a second aspect, the present disclosure also provides a method for preparing a fuel cell sealing plate, which comprises the following steps:

[0021] A fuel cell plate is provided with a sealing groove and a first limiting groove, wherein the first limiting groove is provided below the sealing groove and communicated with the sealing groove;

[0022] Filling the first limiting groove with limiting glue, and the limiting glue exceeds the notch of the first limiting groove;

[0023] Disposing a sealing gasket having a second limiting groove in the sealing groove, so that the notch of the second limiting groove is aligned with the notch of the first limiting groove, and the limiting glue is filled into the second limiting groove; and,

[0024] The limiting glue is cured to form an adhesive limiting body located in the first limiting groove and the second limiting groove.

[0025] In some embodiments of the present disclosure, the step of providing the fuel cell plate includes: forming the first limiting groove at the bottom of the sealing groove of the fuel cell plate, and the method of forming the first limiting groove is selected from mechanical processing, laser ablation or chemical etching.

[0026] In some embodiments of the present disclosure, a method of filling the first limiting groove with limiting glue is selected from screen printing, dispensing, spraying or integrated injection molding.

[0027] In some embodiments of the present disclosure, the material of the sealing gasket includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber; and / or,

[0028] The material of the limiting glue includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber.

[0029] In some embodiments of the present disclosure, the temperature for curing the limiting glue is 20°C to 150°C.

[0030] In a third aspect, the present disclosure further provides a fuel cell, comprising a plurality of fuel cell sealing plates as described in any of the above embodiments, or the fuel cell comprises a plurality of fuel cell sealing plates prepared by the preparation method as described in any of the above embodiments, wherein the plurality of fuel cell sealing plates are arranged in parallel in sequence, and the sealing is achieved between two adjacent fuel cell sealing plates by the sealing gasket.

[0031] The fuel cell sealing plate in at least one of the above embodiments includes a fuel cell plate, a sealing gasket and an adhesive limiting body. Among them, a first limiting groove is further provided in the sealing groove of the fuel cell plate, and a second limiting groove is provided on the surface of the sealing gasket, and the first limiting groove and the second limiting groove are filled with an adhesive limiting body. The adhesive limiting body has both bonding and limiting functions, and the two functions cooperate with each other and synergize to significantly improve the sealing effect of the sealing gasket. On the one hand, the adhesive limiting body allows the sealing gasket to be bonded to the sealing groove in a non-planar manner, with a large contact area and high bonding strength. It is not easy to shift after bonding, which can reduce the generation of micro gas channels, thereby obtaining a better sealing effect. In addition, through the bonding and limiting effects of the adhesive limiting body, the sealing gasket is not easy to shift laterally even when operating in a gas environment with a higher pressure, and the sealing reliability is better. It is also difficult to separate the sealing gasket from the sealing groove, and has good sealing durability.

[0032] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without creative work.

[0034] Figure 1 It is a structural schematic diagram of a fuel cell sealing plate;

[0035] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the sealing groove of the fuel cell sealing plate

[0036] Figure 3 for Figure 2 A schematic diagram of the split structure of the structure shown;

[0037] Figure 4 is a schematic diagram of the cross-sectional structure of a sealing groove of a fuel cell sealing plate in another embodiment;

[0038] Figure 5 is a schematic diagram of the cross-sectional structure of a sealing groove of a fuel cell sealing plate in another embodiment;

[0039] Figure 6 is a schematic diagram of the cross-sectional structure of a sealing groove of a fuel cell sealing plate in another embodiment;

[0040] Figure 7 is a schematic diagram of the cross-sectional structure of a sealing groove of a fuel cell sealing plate in another embodiment;

[0041] Figure 8 A schematic diagram of the steps of a method for preparing a sealed plate for a fuel cell;

[0042] Fig. 9 It is a schematic diagram of the cross-sectional structure of a fuel cell plate provided with a sealing groove and a first limiting groove;

[0043] Fig.10 For Fig. 9 Schematic diagram of the cross-sectional structure filled with limiting glue based on the structure shown.

[0044] The reference numerals and their meanings are as follows:

[0045] 110, fuel cell plate; 111, sealing groove; 112, first limiting groove; 113, anode side surface; 114, cathode side surface; 115, fuel channel; 116, oxidant channel; 117, coolant channel; 120, sealing gasket; 121, second limiting groove; 130, adhesive limiting body. DETAILED DESCRIPTION

[0046] To facilitate understanding of the present invention, a more comprehensive description of the present invention is provided below. The preferred embodiments of the present invention are given herein. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the content of the present invention more thorough and comprehensive.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this document pertains. The terms used herein in the specification of this document are only for describing specific embodiments and are not intended to limit this document.

[0048] It should be understood that when an element or layer is referred to as being "on, "adjacent to, "connected to, or "coupled to" another element or layer, it may be directly on, adjacent to, connected to, or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, "directly adjacent to, "directly connected to, or "directly coupled to" another element or layer, there may be no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion.

[0049] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," and the like may be used herein for ease of description to describe the relationship of one element or feature to other elements or features. It should be understood that the spatially relative terms are intended to also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "over" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be otherwise oriented (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used may be interpreted accordingly.

[0050] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present disclosure. When used herein, the singular forms "a", "an" and "the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0051] The present disclosure provides a fuel cell sealing plate, which includes a fuel cell plate, a sealing gasket and an adhesive limiting body. A sealing groove and a first limiting groove are provided on the fuel cell plate, and the first limiting groove is provided below the sealing groove and communicated with the sealing groove. The sealing gasket is provided in the sealing groove, and a second limiting groove aligned with the first limiting groove is provided on the surface of the sealing gasket near the bottom wall of the sealing groove, and the adhesive limiting body is filled in the first limiting groove and the second limiting groove.

[0052] The fuel cell sealing plate comprises a fuel cell plate, a sealing gasket and an adhesive limiting body. Among them, a first limiting groove is further provided in the sealing groove of the fuel cell plate, a second limiting groove is provided on the surface of the sealing gasket, and the first limiting groove and the second limiting groove are filled with an adhesive limiting body. The adhesive limiting body has both bonding and limiting functions, and the two functions cooperate with each other and synergize to significantly improve the sealing effect of the sealing gasket. On the one hand, the adhesive limiting body allows the sealing gasket to be bonded to the sealing groove in a non-planar manner, with a large contact area and high bonding strength. It is not easy to shift after bonding, and the generation of micro gas channels can be reduced, thereby obtaining a better sealing effect. Moreover, through the bonding and limiting effects of the adhesive limiting body, the sealing gasket is not easy to shift laterally even when operating in a gas environment with a higher pressure, and the sealing reliability is better. It is also difficult to separate the sealing gasket from the sealing groove, and has good sealing durability.

[0053] Figure 1 Schematic diagram of the structure of a fuel cell sealing plate disclosed in the present invention. Figure 1 As shown, the fuel cell sealing plate includes a fuel cell plate and a sealing gasket. A sealing groove is provided on the fuel cell substrate, and the sealing gasket is provided in the sealing groove.

[0054] Reference Figure 1 As shown, as an example of this embodiment, the fuel cell sealing plate can be a bipolar plate in a fuel cell. The bipolar plate has an opposite anode side surface and a cathode side surface, and an anode side flow channel can be provided on the anode side surface, and a cathode side flow channel can be provided on the cathode side surface. Further, a sealing groove 111 and a sealing gasket 120 are provided on both sides of the opposite sides of the fuel cell sealing plate. The sealing groove 111 located on the anode side surface 113 is arranged around the anode side flow channel to seal the gas in the anode side flow channel. The sealing groove 111 located on the cathode side surface 114 is arranged around the cathode side flow channel to seal the gas in the cathode side flow channel.

[0055] Reference Figure 1 As shown in some examples of this embodiment, the fuel cell sealing plate is also provided with a fuel channel 115 connected to the anode side flow channel and an oxidant channel 116 connected to the cathode side flow channel. Both sealing grooves 111 are provided around the fuel channel 115 and the oxidant channel 116.

[0056] Reference Figure 1 As shown, as some examples of this embodiment, a coolant channel 117 is further provided in the fuel cell sealing plate, and two sealing grooves 111 are both provided around the coolant channel 117 .

[0057] Further, Figure 2 for Figure 1A schematic diagram of the cross-sectional structure of the sealing groove 111 of the fuel cell sealing plate, Figure 3 for Figure 2 Schematic diagram of the split structure of the structure shown. Figure 1~Figure 3 As shown, a first limiting groove 112 is also provided on the fuel cell plate 110, and the first limiting groove 112 is provided below the sealing groove 111 and communicated with the sealing groove 111. A second limiting groove 121 is provided on the surface of the groove bottom wall of the sealing gasket 120 close to the sealing groove 111, which is aligned with the first limiting groove 112. The fuel cell sealing plate also includes an adhesive limiting body 130, which is filled in the first limiting groove 112 and the second limiting groove 121.

[0058] Reference Figure 2 and Figure 3 As shown, it can be understood that in this embodiment, the notch of the first limiting groove 112 is opened on the groove bottom wall of the sealing groove 111. The notch of the second limiting groove 121 is opened on the surface of the sealing gasket 120 close to the groove bottom wall of the sealing groove 111. The adhesive limiting body 130 has a portion located in the first limiting groove 112 and a portion exceeding the first limiting groove 112 and located in the second limiting groove 121.

[0059] As an example of this embodiment, the adhesive limiting body 130 may fill up the first limiting groove 112 and the second limiting groove 121 .

[0060] As an example of this embodiment, the number of the first limiting grooves 112 is 1 to 10. In some examples, the number of the first limiting grooves 112 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0061] In this example, the number of the first limiting grooves 112 is 1 to 10, which is beneficial for each first limiting groove 112 to have a relatively sufficient setting space, ensuring that each first limiting groove 112 has a larger adhesion area and a stronger limiting effect.

[0062] As an example of this embodiment, a plurality of first limiting grooves 112 are provided on the fuel cell plate 110 , and a plurality of second limiting grooves 121 are correspondingly provided on the surface of the bottom wall of the sealing groove 111 of the sealing gasket 120 .

[0063] In this example, a plurality of first limiting grooves 112 and second limiting grooves 121 are provided on the fuel cell substrate, and each of the first limiting grooves 112 and second limiting grooves 121 and the adhesive limiting body 130 filled therein can serve as an anchor point between the sealing gasket 120 and the sealing groove 111, thereby further increasing the displacement resistance between the sealing gasket 120 and the sealing groove 111, and further improving the sealing effect of the sealing gasket 120.

[0064] Reference Figure 2 and Figure 3 As shown, in this embodiment, the number of the first limiting grooves 112 may be two.

[0065] As an example of this embodiment, the extension direction of each first limiting groove 112 intersects with the width direction of the sealing groove 111 , and the plurality of first limiting grooves 112 are spaced apart and arranged in sequence in the width direction of the sealing groove 111 .

[0066] In such Figure 2 and Figure 3 In the embodiment shown, the width direction of the sealing groove 111 is the left-right direction, and the extension direction of the first limiting groove 112 is Figure 2 and Figure 3 The vertical direction of the plane.

[0067] In this example, when the sealing gasket 120 is impacted by the high-pressure gas, it usually moves laterally along the width direction of the sealing groove 111. In this embodiment, the extension direction of the plurality of first limiting grooves 112 is set to intersect with the width direction of the sealing groove 111, which has a stronger blocking and limiting effect on the sealing gasket 120 in the width direction of the sealing groove 111, thereby reducing or avoiding the lateral displacement of the sealing gasket 120.

[0068] As a further example of this embodiment, the plurality of first limiting grooves 112 are arranged in parallel and perpendicular to the width direction of the sealing groove 111. However, in other examples, the plurality of first limiting grooves 112 may not be arranged in parallel.

[0069] As an example of an embodiment, the cross-sectional area of ​​the first limiting groove 112 in its depth direction is 0.4 mm 2 ~5mm 2 In some examples, the cross-sectional area of ​​the first limiting groove 112 in the depth direction thereof may be 0.4 mm. 2 , 0.5mm 2 , 0.6mm 2 , 1mm 2 , 1.5mm 2 , 2mm 2 , 3mm 2 , 4mm 2 , 5mm 2 Alternatively, the cross-sectional area of ​​the first limiting groove 112 in its depth direction may also be between any two of the above areas.

[0070] In this example, the cross-sectional area of ​​the first limiting groove 112 is set to 0.4 mm 2 ~5mm 2, which can ensure that there is a relatively large contact area between the adhesive limiting body 130 and the groove wall of the first limiting groove 112, and can also reduce or avoid the negative impact of the first limiting groove 112 on the performance of the fuel cell plate 110.

[0071] As an example of an embodiment, the cross-sectional area of ​​the second limiting groove 121 in its depth direction is 0.4 mm 2 ~5mm 2 In some examples, the cross-sectional area of ​​the second limiting groove 121 in the depth direction thereof may be 0.4 mm. 2 , 0.5mm 2 , 0.6mm 2 , 1mm 2 , 1.5mm 2 , 2mm 2 , 3mm 2 , 4mm 2 , 5mm 2 Alternatively, the cross-sectional area of ​​the second limiting groove 121 in its depth direction may also be between any two of the above areas.

[0072] In this example, the cross-sectional area of ​​the second limiting groove 121 is set to 0.4 mm 2 ~5mm 2 , which can ensure that there is a relatively large contact area between the adhesive limiting body 130 and the groove wall of the second limiting groove 121, and can also reduce or avoid the negative impact of the second limiting groove 121 on the performance of the sealing gasket 120.

[0073] Reference Figure 2 and Figure 3 As shown, as an example of this embodiment, along the direction from the notch of the first limiting groove 112 toward the bottom wall thereof, the radial dimension of the first limiting groove 112 remains unchanged.

[0074] In this example, by setting the cross-sectional size of the first limiting groove 112 to remain unchanged, the adhesive limiting body 130 has a higher strength along the direction close to the notch of the first limiting groove 112, and the adhesive limiting body 130 is less likely to break when the sealing gasket 120 is impacted, thereby further improving the reliability of the use of the sealing gasket 120. It can be understood that in other examples, the radial size of the first limiting groove 112 can also be gradually reduced.

[0075] Reference Figure 2 and Figure 3 As shown, as an example of this embodiment, along the direction from the notch of the second limiting groove 121 toward the bottom wall thereof, the radial dimension of the second limiting groove 121 remains unchanged.

[0076] In this example, by setting the cross-sectional size of the second limiting groove 121 to remain unchanged, the adhesive limiting body 130 has a higher strength along the direction of the notch close to the second limiting groove 121, and the adhesive limiting body 130 is less likely to break when the sealing gasket 120 is impacted, thereby further improving the reliability of the use of the sealing gasket 120. It can be understood that in other examples, the radial size of the second limiting groove 121 can also be gradually reduced.

[0077] Reference Figure 2 and Figure 3 As shown, in this embodiment, along the direction from the notch of the first limiting groove 112 to the bottom wall of the groove, the cross section of the first limiting groove 112 may be rectangular. Along the direction from the notch of the second limiting groove 121 to the bottom wall of the groove, the cross section of the second limiting groove 121 may be rectangular. In other embodiments, along the direction from the notch to the bottom wall of the groove, the cross sections of the first limiting groove 112 and the second limiting groove 121 may also be independently selected from an inverted triangle, a semicircle, a semi-ellipse, an inverted trapezoid, or other polygons with more than 4 sides.

[0078] Reference Figure 2 and Figure 3 As shown, as an example of this embodiment, the orthographic projection of the notch of the second limiting groove 121 on the notch of the first groove coincides with the notch of the first groove.

[0079] When in use, the adhesive limiter 130 is located between the first limit groove 112 and the second limit groove 121. The structure is subjected to the greatest impact and is more likely to break. In this example, the notch of the second limit groove 121 is arranged to overlap with the notch of the first limit groove 112, which can avoid misalignment between the upper and lower halves of the adhesive limiter 130, which is conducive to further enhancing the strength and stability of the middle part of the adhesive limiter 130.

[0080] As a further example of this embodiment, the shape of the second limiting groove 121 is mirror-symmetrical to the shape of the first groove.

[0081] As some examples of this embodiment, the sealing gasket 120 is a rubber sealing gasket 120. In some examples, the material of the rubber sealing gasket 120 may include one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber.

[0082] As some examples of this embodiment, the adhesive limiter 130 is a solid structure formed after the glue is cured. The glue may include a rubber material. In some examples, the rubber material in the glue includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber.

[0083] In this example, the materials of the sealing pad 120 and the adhesive stopper 130 may be the same or different.

[0084] In this example, compared with other materials, the rubber gasket 120 is more effective in blocking gas, and can prevent diffusion and leakage from the inside of the rubber gasket 120, ensuring that the gasket 120 has good gas barrier performance. Combined with the design of the adhesive stopper 130, the structure composed of the gasket 120, the sealing groove 111 and the adhesive stopper 130 can effectively block gas leakage from the sealing groove 111.

[0085] As an example of this embodiment, the adhesive limiting body 130 is also extended and disposed between the sealing gasket 120 and the bottom wall of the sealing groove 111 .

[0086] In this embodiment, the adhesive limiter 130 extending between the sealing gasket 120 and the bottom wall of the sealing groove 111 can act as a reinforcing rib, thereby further improving the bonding strength between the adhesive limiter 130 and the bottom wall of the sealing groove 111 and the sealing gasket 120 .

[0087] Figure 4 FIG. 1 is a schematic diagram of a cross-sectional structure of a sealing groove 111 of a fuel cell sealing plate in another embodiment. Figure 4 As shown, the fuel cell plate 110 is also provided with a sealing groove 111 and a first limiting groove 112, the first limiting groove 112 is provided below the sealing groove 111 and communicates with the sealing groove 111, the sealing gasket 120 is provided in the sealing groove 111, and the sealing gasket 120 is provided with a second limiting groove 121 aligned with the first limiting groove 112 on the surface of the groove bottom wall close to the sealing groove 111. The adhesive limiting body 130 is filled in the first limiting groove 112 and the second limiting groove 121.

[0088] Figure 4 The structure shown is Figure 2 The difference between the structures shown mainly lies in the shapes of the first limiting groove 112 and the second limiting groove 121. Figure 4 As shown, as an example of this embodiment, along the direction from the notch of the first limiting groove 112 to the bottom wall thereof, the radial dimension of the first limiting groove 112 gradually decreases. Along the direction from the notch of the second limiting groove 121 to the bottom wall thereof, the radial dimension of the second limiting groove 121 gradually decreases.

[0089] Reference Figure 4As shown, as an example of this embodiment, along the direction from the notch of the first limiting groove 112 to the bottom wall of the groove, the cross section of the first limiting groove 112 may be in an inverted trapezoid. Along the direction from the notch of the second limiting groove 121 to the bottom wall of the groove, the cross section of the second limiting groove 121 may be in an inverted trapezoid. Further, corresponding to the shapes of the first limiting groove 112 and the second limiting groove 121, the cross section of the adhesive limiting body 130 may be a hexagon composed of two inverted trapezoids.

[0090] Figure 5 FIG. 1 is a schematic diagram of a cross-sectional structure of a sealing groove 111 of a fuel cell sealing plate in another embodiment. Figure 5 As shown, the fuel cell plate 110 is also provided with a sealing groove 111 and a first limiting groove 112, the first limiting groove 112 is provided below the sealing groove 111 and communicates with the sealing groove 111, the sealing gasket 120 is provided in the sealing groove 111, and the sealing gasket 120 is provided with a second limiting groove 121 aligned with the first limiting groove 112 on the surface of the groove bottom wall close to the sealing groove 111. The adhesive limiting body 130 is filled in the first limiting groove 112 and the second limiting groove 121.

[0091] Figure 5 The structure shown is Figure 2 The difference between the structures shown mainly lies in the shapes of the first limiting groove 112 and the second limiting groove 121. Figure 5 As shown, as an example of this embodiment, along the direction from the notch of the first limiting groove 112 to the bottom wall of the groove, the cross section of the first limiting groove 112 can be semicircular or semi-elliptical. Along the direction from the notch of the second limiting groove 121 to the bottom wall of the groove, the cross section of the second limiting groove 121 can be semicircular or semi-elliptical. Further, corresponding to the shapes of the first limiting groove 112 and the second limiting groove 121, the cross section of the adhesive limiting body 130 can be a circle composed of two semicircles, or an ellipse composed of two semi-ellipses.

[0092] Figure 6 FIG. 1 is a schematic diagram of a cross-sectional structure of a sealing groove 111 of a fuel cell sealing plate in another embodiment. Figure 6 As shown, the fuel cell plate 110 is also provided with a sealing groove 111 and a first limiting groove 112, the first limiting groove 112 is provided below the sealing groove 111 and communicates with the sealing groove 111, the sealing gasket 120 is provided in the sealing groove 111, and the sealing gasket 120 is provided with a second limiting groove 121 aligned with the first limiting groove 112 on the surface of the groove bottom wall close to the sealing groove 111. The adhesive limiting body 130 is filled in the first limiting groove 112 and the second limiting groove 121.

[0093] Figure 6 The structure shown is Figure 2 The difference between the structures shown mainly lies in the number and shape of the first limiting grooves 112 and the second limiting grooves 121. Figure 6 As shown, as an example of this embodiment, the number of the first limiting groove 112 and the number of the second limiting groove 121 are each one. Along the direction from the notch of the first limiting groove 112 to the bottom wall of its groove, the cross-section of the first limiting groove 112 can be an inverted trapezoid. Along the direction from the notch of the second limiting groove 121 to the bottom wall of its groove, the cross-section of the second limiting groove 121 can be an inverted trapezoid. Further, corresponding to the shape of the first limiting groove 112 and the second limiting groove 121, the cross-section of the adhesive limiting body 130 can be a hexagon composed of two inverted trapezoids.

[0094] Figure 7 FIG. 1 is a schematic diagram of a cross-sectional structure of a sealing groove 111 of a fuel cell sealing plate in another embodiment. Figure 7 As shown, the fuel cell plate 110 is also provided with a sealing groove 111 and a first limiting groove 112, the first limiting groove 112 is provided below the sealing groove 111 and communicates with the sealing groove 111, the sealing gasket 120 is provided in the sealing groove 111, and the sealing gasket 120 is provided with a second limiting groove 121 aligned with the first limiting groove 112 on the surface of the groove bottom wall close to the sealing groove 111. The adhesive limiting body 130 is filled in the first limiting groove 112 and the second limiting groove 121.

[0095] Figure 7 The structure shown is Figure 2 The difference between the structures shown mainly lies in the number and shape of the first limiting grooves 112 and the second limiting grooves 121. Figure 7 As shown, as an example of this embodiment, the number of the first limiting groove 112 and the number of the second limiting groove 121 are three. Along the direction from the notch of the first limiting groove 112 to the bottom wall of its groove, the cross section of the first limiting groove 112 can be an inverted triangle. Along the direction from the notch of the second limiting groove 121 to the bottom wall of its groove, the cross section of the second limiting groove 121 can be an inverted triangle. Further, corresponding to the shape of the first limiting groove 112 and the second limiting groove 121, the cross section of the adhesive limiting body 130 can be a rhombus composed of two inverted triangles.

[0096] The present disclosure also provides a method for preparing a fuel cell sealing plate. Figure 8 Schematic diagram of the steps of the preparation method. Figure 8 As shown, the preparation method includes steps S1 to S4, which are specifically as follows.

[0097] Step S1 , providing a fuel cell plate 110 provided with a sealing groove 111 and a first limiting groove 112 .

[0098] Fig. 9 1 is a schematic diagram of the cross-sectional structure of a fuel cell plate 110 provided with a sealing groove 111 and a first limiting groove 112. Fig. 9 As shown, the first limiting groove 112 is disposed below the sealing groove 111 and communicated with the sealing groove 111 .

[0099] As an example of this embodiment, the step of providing a fuel cell plate 110 includes: forming a first limiting groove 112 at the bottom of the sealing groove 111 of the fuel cell plate 110, and the method of forming the first limiting groove 112 is selected from mechanical processing, laser ablation or chemical etching.

[0100] The fuel cell plates 110 in the conventional technology are all provided with sealing grooves 111. In this example, the first limiting groove 112 is formed at the bottom of the sealing groove 111 by mechanical processing, laser ablation or chemical etching. The formation process is relatively simple, and only an additional grooving process is required compared with the conventional technology, which does not significantly increase the process and process difficulty, and has high practicality.

[0101] As a further example of this embodiment, the mechanical processing method may be but is not limited to milling. The chemical etching method may be dry etching or wet etching.

[0102] It can be understood that the shapes and specific configurations of the sealing groove 111 and the first limiting groove 112 in this embodiment can refer to Figure 2 The fuel cell sealing plates in the illustrated embodiment are configured accordingly and will not be described in detail here.

[0103] Step S2, filling the first limiting groove 112 with limiting glue.

[0104] Fig.10 For Fig. 9 The schematic diagram of the cross-sectional structure of the structure shown is filled with limiting glue. Fig.10 As shown, the limiting glue exceeds the notch of the first limiting groove 112 .

[0105] As an example of this embodiment, the method of filling the limiting glue in the first limiting groove 112 is selected from screen printing, dispensing, spraying or integrated injection molding.

[0106] In this example, by adopting the methods of screen printing, dispensing, spraying or integrated injection molding, the coating position and coating amount of the limiting glue can be made more precise, thereby obtaining an adhesive limiting body 130 of better quality.

[0107] As an example of this embodiment, the material of the limiting glue includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber.

[0108] In this example, compared with other materials, the rubber material is more effective in blocking gas, and can prevent diffusion and leakage from the inside of the adhesive limiter 130, ensuring that the adhesive limiter 130 has good gas barrier performance. In addition, the use of the above-mentioned limit glue containing rubber components can generate stronger adhesion with the sealing gasket 120, and can also reduce micro gas channels in the limit glue.

[0109] Step S3 , disposing the sealing gasket 120 having the second limiting groove 121 in the sealing groove 111 , and filling the second limiting groove 121 with limiting glue.

[0110] In this embodiment, when the sealing gasket 120 having the second limiting groove 121 is disposed in the sealing groove 111 , the notch of the second limiting groove 121 can be aligned with the notch of the first limiting groove 112 .

[0111] It can be understood that in this embodiment, since the limiting glue in step S2 exceeds the notch of the first limiting groove 112, when the sealing gasket 120 is set in the sealing groove 111, the limiting glue located above the notch of the first limiting groove 112 will fill the second limiting groove.

[0112] As an example of this embodiment, the material of the sealing gasket 120 includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber, and EPDM rubber.

[0113] In this embodiment, compared with other materials, the rubber material is more effective in blocking gas, and can prevent diffusion and leakage from the inside of the sealing gasket 120, ensuring that the sealing gasket 120 and the formed adhesive limiter 130 have good barrier properties for gas as a whole. In addition, the use of the sealing gasket 120 containing the rubber component can generate stronger adhesion with the limit glue, and can also reduce the micro gas channels in the limit glue.

[0114] Step S4 , curing the limiting glue to form an adhesive limiting body 130 located in the first limiting groove 112 and the second limiting groove 121 .

[0115] As an example of this embodiment, the method of curing the limiting glue may be room temperature curing or heating curing. As a further example of this embodiment, the temperature for curing the limiting glue is 20°C~150°C. In some examples, the temperature for curing the limiting glue may be 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 120°C, 150°C, or the temperature for curing the limiting glue may be between any two of the above temperatures.

[0116] It can be understood that the curing temperature can be selected according to the material of the limiting glue. For example, when the material of the limiting glue is silicone rubber, it can be cured at room temperature. In addition, in this example, curing the limiting glue at a temperature of 20°C to 150°C can avoid the negative impact of high temperature or low temperature conditions on the reliability of the sealing gasket 120, and ensure that the sealing gasket 120 maintains its original shape and mechanical properties during the curing process. When the curing temperature is too high, the sealing gasket 120 may be heated and ageing accelerated, resulting in a significant shortening of its service life. When the curing temperature is too low, the sealing gasket 120 may become cold and brittle, resulting in a significant decrease in its barrier performance to gases.

[0117] It can be understood that after the above steps S1 to S4, the following Figure 2 A fuel cell sealing plate is shown.

[0118] In this embodiment, by coating the limiting glue in the first limiting groove 112 and then setting the sealing gasket 120 in the sealing groove 111, the limiting glue exceeding the notch of the first limiting groove 112 will be squeezed and filled in the second limiting groove 121 in the sealing gasket 120. The limiting glue is in-situ cured in the first limiting groove 112 and the second limiting groove 121, so that it has a strong adhesive force with the groove wall. After curing, the limiting glue forms an adhesive limiting body 130, so that it can also have a good limiting effect at the same time.

[0119] Furthermore, the present disclosure also provides a fuel cell, which includes multiple fuel cell sealing plates as in any of the above embodiments, or the fuel cell includes multiple fuel cell sealing plates prepared by the preparation method of any of the above embodiments, and the multiple fuel cell sealing plates are arranged in parallel in sequence, and sealing is achieved between two adjacent fuel cell sealing plates by a sealing gasket 120.

[0120] As an example of this embodiment, the fuel cell may further include a membrane electrode, which is disposed between two adjacent fuel cell sealing plates.

[0121] As an example of this embodiment, the fuel cell may also include two end plates that are disposed opposite to each other, and a plurality of fuel cell sealing plates are stacked between the two end plates.

[0122] The present application is further described in detail below in conjunction with several specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0123] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0124] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used that do not specify the manufacturer are all conventional products that can be obtained commercially.

[0125] Example 1

[0126] A fuel cell bipolar plate having a sealing groove on the periphery is provided. A first limiting groove is opened on the bottom wall of the sealing groove along the extending direction of the sealing groove by CNC processing. The cross section of the first limiting groove is an inverted trapezoidal structure with a larger upper portion and a smaller lower portion, and the cross-sectional area is 1 mm 2 .

[0127] The first limiting groove is filled with silicone rubber glue by dispensing, and the amount of glue slightly exceeds the notch of the first limiting groove.

[0128] A sealing gasket with a second limiting groove is pressed into the sealing groove. The material of the sealing gasket is silicone rubber. The cross-sectional shape of the second limiting groove is symmetrical to the cross-sectional shape of the first limiting groove. The notch of the second limiting groove is aligned with the first limiting groove, and the glue fills the first limiting groove and the second limiting groove.

[0129] The glue is cured at room temperature to form adhesive limiting bodies in the first limiting groove and the second limiting groove.

[0130] Multiple fuel cell bipolar plates and sealing gaskets are stacked in sequence to form a fuel cell.

[0131] Example 2

[0132] The only difference between Example 2 and Example 1 is that the cross-sections of the first limiting groove and the second limiting groove of Example 2 are rectangular.

[0133] Example 3

[0134] The only difference between Example 3 and Example 1 is that the cross-sectional area of ​​the first limiting groove and the second limiting groove of Example 3 is 0.05 mm 2 .

[0135] Example 4

[0136] The only difference between Example 4 and Example 1 is that the cross-sectional area of ​​the first limiting groove and the second limiting groove of Example 4 is 5 mm 2 .

[0137] Example 5

[0138] The only difference between Example 5 and Example 1 is that: in Example 5, there are three first limiting grooves and three second limiting grooves, the three first limiting grooves are parallel to each other, and the three second limiting grooves are parallel to each other.

[0139] Comparative Example 1

[0140] The only difference between Comparative Example 1 and Example 1 is that the sealing groove in Comparative Example 1 does not have a first limiting groove, and the sealing gasket does not have a second limiting groove.

[0141] Comparative Example 2

[0142] The only difference between Comparative Example 2 and Example 1 is that the sealing groove in Comparative Example 2 has a first limiting groove, and the sealing gasket does not have a second limiting groove.

[0143] Comparative Example 3

[0144] The only difference between Comparative Example 3 and Example 1 is that the sealing gasket in Comparative Example 3 has a second limiting groove, and the sealing groove does not have a first limiting groove.

[0145] Experiment: The fuel cells of the above-mentioned embodiments and comparative examples were subjected to a pressure test under a gas pressure of 150 kPa, and the pressure drops in the fuel channel, oxidant channel and coolant channel of each fuel cell were measured. The results can be seen in Table 1.

[0146] Table 1

[0147]

[0148] Refer to the above embodiments, comparative examples and the contents of Table 1. Embodiments 1 to 5 all adopt the fuel cell sealing plate structure disclosed in the present invention, and no obvious pressure drop occurs in the coolant channel during the pressure test. In contrast, the first limiting groove and the second limiting groove are not set in Comparative Example 1, and the coolant channel pressure drop, the fuel channel pressure drop and the oxidant channel pressure drop are significantly higher than those in Embodiments 1 to 5. In addition, only a single first limiting groove is set in Comparative Example 2, and only a single second limiting groove is set in Comparative Example 3. Compared with Comparative Example 1, the pressure drop of each channel in Comparative Example 2 and Comparative Example 3 is only reduced by 0.1kP. Quantitative analysis shows that compared with Comparative Example 1, the reduction in Example 1 is higher than the sum of the reductions in Comparative Example 2 and Comparative Example 3, which shows that the first limiting groove and the second limiting groove have a synergistic effect in reducing the pressure drop, and further shows that the simultaneous setting of the first limiting groove and the second limiting groove can significantly improve the sealing performance.

[0149] The pressure drops of the fuel channel and the oxidant channel of Example 1 are both 0.2 kPa. Compared with Example 1, the pressure drops of the fuel channel and the oxidant channel of Examples 2 and 3 are basically the same, indicating that similar sealing effects can be obtained by using other shapes or using first limiting grooves and second limiting grooves with smaller cross-sectional areas. The pressure drop of the fuel channel and the oxidant channel of Example 4 is only 0.1 kPa, indicating that as the cross-sectional area of ​​the first limiting groove and the second limiting groove increases, the sealing performance is also improved. However, the cross-sectional area is not suitable for unlimited increase. As the cross-sectional area further increases to greater than 5 mm 2 , the sealing performance may be reduced, mainly because the excessively large limiting grooves will have a negative impact on the strength of the gasket. In Example 5, there are three first limiting grooves and three second limiting grooves, and the pressure drop of the fuel channel and the oxidant channel is only 0.1 kPa, indicating that as the number of limiting grooves increases, it is beneficial to further enhance the sealing performance. However, the number of limiting grooves is not suitable for unlimited increase, otherwise it will not only have a negative impact on the strength of the gasket, but also make the processing more complicated.

[0150] Please note that the above embodiments are for illustrative purposes only and are not meant to be limiting of this document.

[0151] It should be understood that, unless otherwise specified herein, there is no strict order restriction for the execution of the steps, and the steps may be executed in other orders. Moreover, at least a portion of the steps in the preparation process may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but may be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0152] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0153] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A fuel cell sealing plate, characterized in that: It includes a fuel cell plate, a sealing gasket and an adhesive limiter; The fuel cell plate is provided with a sealing groove and a first limiting groove, wherein the first limiting groove is provided below the sealing groove and communicated with the sealing groove; The sealing gasket is arranged in the sealing groove, and a second limiting groove aligned with the first limiting groove is arranged on the surface of the sealing gasket close to the bottom wall of the sealing groove, and the adhesive limiting body is filled in the first limiting groove and the second limiting groove.

2. The fuel cell sealing plate according to claim 1, characterized in that: The fuel cell plate is provided with a plurality of the first limiting grooves, and the sealing gasket is correspondingly provided with a plurality of the second limiting grooves on the surface of the groove bottom wall close to the sealing groove; Optionally, the number of the first limiting grooves is 1 to 10.

3. The fuel cell sealing plate according to claim 2, characterized in that: An extension direction of each of the first limiting grooves intersects with a width direction of the sealing groove, and a plurality of the first limiting grooves are spaced apart and arranged in sequence in the width direction of the sealing groove.

4. The fuel cell sealing plate according to any one of claims 1 to 3, characterized in that: The cross-sectional area of ​​the first limiting groove in its depth direction is 0.4 mm 2 ~5mm 2 and / or, The cross-sectional area of ​​the second limiting groove in its depth direction is 0.4 mm 2 ~5mm 2 .

5. The fuel cell sealing plate according to claim 4, characterized in that: Along the direction from the notch of the first limiting groove to the bottom wall thereof, the radial dimension of the first limiting groove gradually shrinks; or, Along the direction from the notch of the first limiting groove toward the bottom wall thereof, the radial dimension of the first limiting groove remains unchanged.

6. The fuel cell sealing plate according to any one of claims 1 to 3 and 5, characterized in that: The sealing gasket is a rubber sealing gasket; and / or, The adhesive limiter is a solid structure formed after the glue is cured; and / or, The adhesive limiting body is also extended and arranged between the sealing pad and the bottom wall of the sealing groove.

7. A method for preparing a fuel cell sealing plate, characterized in that: The steps include: A fuel cell plate is provided with a sealing groove and a first limiting groove, wherein the first limiting groove is provided below the sealing groove and communicated with the sealing groove; Filling the first limiting groove with limiting glue, and the limiting glue exceeds the notch of the first limiting groove; Disposing a sealing gasket having a second limiting groove in the sealing groove, so that the notch of the second limiting groove is aligned with the notch of the first limiting groove, and the limiting glue is filled into the second limiting groove; and, The limiting glue is cured to form an adhesive limiting body located in the first limiting groove and the second limiting groove.

8. The method for preparing a fuel cell sealing plate according to claim 7, characterized in that: The step of providing the fuel cell plate comprises: forming the first limiting groove at the bottom of the sealing groove of the fuel cell plate, wherein the method of forming the first limiting groove is selected from mechanical processing, laser ablation or chemical etching; and / or, The method of filling the first limiting groove with limiting glue is selected from screen printing, dispensing, spraying or integrated injection molding.

9. The method for preparing a fuel cell sealing plate according to any one of claims 7 to 8, characterized in that: The material of the sealing gasket includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber; and / or, The material of the limiting glue includes one or more of silicone rubber, fluororubber, nitrile rubber, chloroprene rubber, butyl rubber and EPDM rubber; and / or, The temperature for curing the limiting glue is 20°C to 150°C.

10. A fuel cell, characterized in that: The fuel cell comprises a plurality of fuel cell sealing plates as described in any one of claims 1 to 6, or the fuel cell comprises a plurality of fuel cell sealing plates prepared by the preparation method as described in any one of claims 7 to 9, wherein the plurality of fuel cell sealing plates are arranged in parallel in sequence, and the sealing gasket is used to seal two adjacent fuel cell sealing plates.

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