Sealing mechanism and alkaline hydrogen production electrolytic cell

Abstract

The invention relates to the technical field of hydrogen production from renewable energy sources, in particular to a sealing mechanism which comprises a plurality of bipolar plates stacked in sequence and sealing gaskets used for blocking gaps between every two adjacent bipolar plates, a plurality of grooves are formed in the two sides of each bipolar plate, each groove is composed of a first face, a second face and a third face, and the first faces, the second faces and the third faces are arranged in parallel. The sealing gasket is provided with a sealing ring corresponding to the groove; the thickness of the section of the sealing ring is gradually reduced outwards from the bipolar plate; the inclination angle between the first surface and the second surface is alpha, and the inclination angle between the second surface and the third surface is beta; according to the technical scheme, through dynamic pressure response, multiple sealing interfaces and application of elastic materials, the high-pressure sealing problem of a traditional electrolytic cell is solved, the sealing stability and the anti-pressure capacity are remarkably improved, the pressure between bipolar plates can be effectively monitored, the pressure can be monitored in real time, and the service life of the electrolytic cell is prolonged. And the sealing effect is prevented from being influenced by pressure reduction.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of renewable energy hydrogen production, and in particular to a sealing mechanism and an alkaline hydrogen production electrolytic cell. BACKGROUND

[0002] With the transformation of global energy structure to low carbonization, hydrogen energy is regarded as an ideal energy storage carrier due to its high quality energy density (up to 120-142 MJ / kg), combustion product only water and zero carbon emission. Compared with the traditional fossil fuel hydrogen production process, the water electrolysis hydrogen production technology prepares high-purity hydrogen (the purity can be up to more than 99.9999%) by electrochemical decomposition of water molecules, has high technical maturity and relatively simple equipment structure, and has significant advantages in environmental friendliness: the electrolysis process only produces hydrogen and oxygen byproducts, and no carbon dioxide and other pollutants are discharged in the whole life cycle. With the large-scale development of the hydrogen energy industry, the alkaline electrolysis water hydrogen production technology has become the most widely used electrolysis water hydrogen production scheme due to its high equipment maturity (the single-tank hydrogen production capacity can reach 1000 Nm 3 / h), low operation cost (unit energy consumption is about 4.1-4.5 kWh / Nm 3 H2) and other advantages. The existing alkaline electrolytic cell is usually a circular filter-pressing pressure type electrolytic cell. Each electrolytic chamber of the electrolytic cell is composed of double-sided plates and sealing gaskets. All the double-sided plates and sealing gaskets are alternately stacked to form all the electrolytic chambers. The double-sided plates and sealing gaskets are finally extruded by end pressure plates and fastening bolts to form closed electrolytic chambers different from the outside.

[0003] The traditional circular alkaline hydrogen production electrolytic cell generates axial compression force through the fastening screw rods uniformly distributed at the edges, so that the sealing interface between the double-sided plates and the sealing gaskets is formed. The pre-tightening force required for sealing is formed through the double-sided plates to form a radial stress distribution from the center to the edge. The compression pre-tightening force between the double-sided plates and the sealing gaskets not only needs to ensure the sealing pressure required by the sealing interface, but also needs to ensure that there is enough friction between the sealing gasket and the double-sided plate to prevent the sealing gasket and the double-sided plate from moving due to gravity. After long-term operation, the sealing pressure is reduced due to the creep and relaxation of the gasket, and the electrolytic cell is deformed from the center to the two sides due to the gravity effect of the double-sided plate. Under the combined action, the double-sided plate and the sealing gasket have electrolyte leakage problems. Therefore, a sealing mechanism and an alkaline hydrogen production electrolytic cell are designed. SUMMARY

[0004] This section is intended to summarize some aspects of the embodiments of the application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, the abstract and the title. Such simplifications or omissions cannot be used to limit the scope of the application.

[0005] In view of the above or the sealing mechanism and the sealing problem of the alkaline hydrogen production electrolytic cell in the prior art, the present application is proposed.

[0006] Therefore, one of the purposes of the present application is to provide a sealing mechanism.

[0007] To solve the above technical problems, the present application provides the following technical solutions: a sealing mechanism, comprising a plurality of bipolar plates stacked in sequence, and a sealing gasket for plugging the gap between two adjacent bipolar plates, the bipolar plates are provided with a plurality of grooves on both sides, the grooves are composed of a first face, a second face and a third face, and the sealing gasket is provided with a sealing ring corresponding to the groove; the cross-sectional thickness of the sealing ring gradually decreases from the sealing gasket outward; the angle between the first face and the second face is α, and the angle between the second face and the third face is β; the angles of α and β satisfy 90°≥α>85°>β≥60°.

[0008] As a preferred scheme of the sealing mechanism of the present application, wherein: the distance between the first face and the surface of the bipolar plate is Z1, the distance between the second face and the third face is Z2, and the diameter of the sealing ring is Z3; the lengths between Z1, Z2 and Z3 satisfy Z2>Z3>Z1; the length between Z1 and Z2 satisfies Z2=2Z1.

[0009] As a preferred scheme of the sealing mechanism of the present application, wherein: the second face is arranged in parallel with the surface of the bipolar plate.

[0010] As a preferred scheme of the sealing mechanism of the present application, wherein: the first face and the surface of the bipolar plate, the first face and the second face, the second face and the third face, and the third face and the surface of the bipolar plate are connected by arc surfaces.

[0011] As a preferred scheme of the sealing mechanism of the present application, wherein: the outer wall of the sealing ring respectively abuts against the first face, the second face and the third face, and the outer wall of the sealing gasket abuts against the outer wall of the bipolar plate.

[0012] As a preferred scheme of the sealing mechanism of the present application, wherein: the sealing ring and the sealing gasket are made of rubber material and are integrally formed by injection molding.

[0013] Another purpose of the present application is to provide an alkaline hydrogen production electrolytic cell, comprising end plates located on both sides of the bipolar plate, and two end plates are connected with the bipolar plate through a connecting assembly, and the connecting assembly is provided with a detection assembly at both ends; the connecting assembly comprises an insulating support located on the upper and lower sides of the bipolar plate, and the insulating support is limited by a fastening screw, and the detection assembly is located at both ends of the fastening screw.

[0014] As a preferred scheme of the alkaline hydrogen production electrolytic cell, the insulating support is connected with the bipolar plate through bolts, pin holes and pin bodies are arranged between the bipolar plate and the insulating support for positioning, and the insulating support is provided with an outer hole corresponding to the fastening screw rod.

[0015] As a preferred scheme of the alkaline hydrogen production electrolytic cell, the detection assembly comprises a mounting seat arranged on the fastening screw rod, a force sensor and a signal sensor are arranged on the mounting seat, a sliding sleeve and a spring are arranged on the side of the mounting seat away from the end plate, and a fastening nut is arranged on the side of the sliding sleeve away from the mounting seat.

[0016] As a preferred scheme of the alkaline hydrogen production electrolytic cell, the spring is arranged between the sliding sleeve and the mounting seat, the sliding sleeve and the mounting seat are in sliding connection with the inner walls of the mounting seat and the sliding sleeve, and the force sensor is arranged between the mounting seat and the spring.

[0017] The sealing mechanism and the alkaline hydrogen production electrolytic cell have the following beneficial effects: the dynamic pressure response, the multiple sealing interfaces and the elastic material application solve the high-pressure sealing problem of the traditional electrolytic cell, significantly improve the sealing stability and the pressure resistance, the technical scheme can effectively monitor the pressure between the bipolar plates, and the pressure is monitored in real time, so that the sealing effect is affected due to the reduction of the pressure. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 It is an internal structure diagram of the sealing mechanism.

[0020] Figure 2 It is a cross-sectional view of the assembled sealing mechanism.

[0021] Figure 3 It is a schematic view of the overall structure of the sealing mechanism.

[0022] Figure 4 It is a schematic view of the overall structure of the alkaline hydrogen production electrolytic cell.

[0023] Figure 5 It is a schematic view of the detection assembly of the alkaline hydrogen production electrolytic cell.

[0024] Figure 6 It is a schematic view of the bipolar plate of the alkaline hydrogen production electrolytic cell.

[0025] Figure 7 It isFigure 6 Enlarged view at A.

[0026] Figure 8 Schematic view of a single bipolar plate after assembly of the insulating support in an alkaline hydrogen production electrolyser. DETAILED DESCRIPTION

[0027] In order to make the above objectives, features and advantages of the present application more apparent, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0028] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details given herein. In other instances, well-known methods have not been described in detail in order to avoid unnecessarily obscuring the present application. Therefore, the specific embodiments given herein are not to be interpreted as limiting the scope of the application.

[0029] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. The "in one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0030] Embodiment 1, with reference to Figures 1-3 In the first embodiment of the present application, the sealing mechanism comprises a plurality of bipolar plates 100 stacked in sequence, and a sealing gasket 200 for plugging the gap between two adjacent bipolar plates 100. The bipolar plates 100 are provided with a plurality of grooves 101 on both sides. The grooves 101 are composed of a first face 101a, a second face 101b and a third face 101c. The sealing gasket 200 is provided with a sealing ring 201 corresponding to the groove 101. The cross-sectional thickness of the sealing ring 201 gradually decreases from the sealing gasket 200 outward, which can better adapt to the groove 101. In this embodiment, the cross-section of the sealing ring 201 is semicircular. The angle between the first face 101a and the second face 101b is α, and the angle between the second face 101b and the third face 101c is β. The angles α and β satisfy 90°≥α>85°>β≥60°.

[0031] Furthermore, when the angle between the first face 101a and the second face 101b exceeds 90°, it will affect the sealing effect of the sealing ring 201. If the angle α exceeds 90° when the sealing ring 201 is under pressure, it will cause the sealing ring 201 to partially cross the first face 101a, thereby affecting the contact area and contact pressure between the sealing ring 201 and the first face 101a and the second face 101b. If the angle α is 86°, it can avoid the sealing ring 201 from shifting after being under pressure, and prevent the sealing ring 201 from sliding out of the first face 101a. Therefore, the preferred range of α is 90°≥α>85°.

[0032] The cross section of the sealing gasket 200 in this embodiment is annular, and the groove 101 is arranged to fit the sealing gasket 200, and the groove 101 and the sealing gasket 200 form a sealed interval, thereby forming a closed chamber at the center of the annular sealing gasket 200. When the bipolar plate 100 extrudes the sealing gasket 200 and the sealing ring 201, the sealing ring 201 deforms, so that the sealing ring 201 tightly fits the three surfaces in the groove 101. When the pressure inside the sealing ring 201 increases, the sealing ring 201 deforms outward, thereby making the sealing ring 201 contact the first surface 101a and the second surface 101b more tightly, and α>β increases the contact area between the inner ring of the sealing ring 201 and the sealed chamber during use, and avoids the sealing ring 201 from separating from the first surface 101a after deformation.

[0033] The distance between the first surface 101a and the surface of the bipolar plate 100 is Z1, which is the groove depth of the groove 101, the distance between the second surface 101b and the third surface 101c is Z1, and the diameter of the sealing ring 201 is Z3; the lengths of Z1, Z2, and Z3 satisfy Z2>Z3>Z1; the length between Z1 and Z2 satisfies Z2=2Z1, and the second surface 101b is arranged in parallel with the surface of the bipolar plate 100.

[0034] Further, the sealing ring 201 deforms after contacting the groove 101, and the sealing ring 201 tightly fits the inside of the groove 101 after deformation. The deformation of the sealing ring 201 during assembly causes the two sides to fill Z2=2Z1, which can reserve enough deformation space for the sealing ring 201, and can better fit the sealing ring 201 to the groove 101 after assembly. The length of Z2 is the distance between the center point of the first surface 101a and the center point of the third surface 101c, and the length of Z3 is less than Z2, so that after assembly, the pressure on the side of the sealing ring 103 close to the third surface 101c is less than the pressure on the side of the first surface 101a, and the sealing ring 201 will shift towards the first surface 101a when the pressure increases during sealing, thereby increasing the sealing effect.

[0035] The first surface 101a and the surface of the bipolar plate 100, the first surface 101a and the second surface 101b, the second surface 101b and the third surface 101c, and the third surface 101c and the surface of the bipolar plate 100 are connected by the arc surface 101d.

[0036] Specifically, the arrangement of the arc surface 101d can effectively fit the deformed sealing ring 201, and at the same time avoid damage to the sealing ring 201 during deformation.

[0037] The outer wall of the sealing ring 201 is in abutment with the first surface 101a, the second surface 101b and the third surface 101c respectively, the outer wall of the sealing gasket 200 is in abutment with the outer wall of the bipolar plate 100, the sealing ring 201 and the sealing gasket 200 are made of rubber material and are integrally formed by injection molding.

[0038] The sealing ring 201 and the groove 101 are provided in plurality, and the plurality of sealing rings 201 and the groove 101 have a gap therebetween, the gap drives the sealing gasket 200 to deform after the bipolar plate 100 is pressed, and simultaneously drives the sealing ring 201 and the groove 101 to be closely attached.

[0039] In summary, the gradually changing cross section of the sealing ring 201 deforms when pressed, and after deformation, it is more closely attached to the first surface 101a, the second surface 101b and the third surface 101c of the groove 101, thereby enhancing the close contact, when the pressure inside the sealing ring 201 rises, the sealing ring 201 is deformed by the thrust force in the direction of the first surface 101a, further pressing the first surface 101a and the second surface 101b, thereby achieving dynamic compensation, avoiding sealing failure under high pressure working condition, and the plurality of sealing rings 201 and the groove 101 form a multi-layer sealing, and the multi-layer sealing layout improves the pressure resistance.

[0040] Embodiment 2, refer to Figures 3-8 The second embodiment of the application is different from the previous embodiment, which is a basic hydrogen production electrolytic cell, comprising end plates 300 located on both sides of the bipolar plate 100, the two end plates 300 are connected with the bipolar plate 100 through a connecting assembly 400, and the connecting assembly 400 is provided with a detection assembly 500 at both ends; the connecting assembly 400 comprises insulating supports 401 located on the upper and lower sides of the bipolar plate 100, the insulating supports 401 are limited by fastening screws 402, and the detection assembly 500 is located at both ends of the fastening screws 402.

[0041] The end plate 300 can effectively clamp the bipolar plate 100, the connecting assembly 400 can effectively connect the bipolar plate 100 and the end plate 300, and the detection assembly 500 can monitor the clamping force between the two end plates 300 in real time, so that the fastening can be timely when the clamping force decreases, thereby avoiding affecting the sealing effect due to the reduction of the clamping force.

[0042] The insulating support 401 is connected with the bipolar plate 100 through a bolt, the bipolar plate 100 and the insulating support 401 are provided with a pin hole 403 and a pin body 404 for positioning, and the insulating support 401 is provided with an outer hole 405 corresponding to the fastening screw 402; the insulating support 401 is arc-shaped and wraps the bipolar plate 100, the outer hole 405 of the prior art is provided on the bipolar plate 100, and the operation of the bipolar plate 100 is easily affected by gravity in a long time stationary state.

[0043] Further, the insulating support 401 is used to support the bipolar plate 100, avoiding the bipolar plate 100 being directly connected with the fastening bolt, and the insulating support 401 being connected with the fastening bolt is compared with the bipolar plate 100 being directly connected, avoiding the bipolar plate 100 being deformed due to gravity in a long-time stationary operation process, and the bipolar plate 100 being deformed will affect the sealing effect between the two bipolar plates 100, compared with the existing increase of the local auxiliary support to the deflection deformation of the middle part of the electrolytic tank caused by gravity, the technical scheme adopts two groups of supports above and below, and the lifting effect is better, and each bipolar plate 100 has supporting force, so that the lifting effect is uniformly distributed on each bipolar plate 100.

[0044] The remaining structures are the same as those in Embodiment 1.

[0045] In summary, the bipolar plate 100 in the device can bear force uniformly, the running safety and the maintenance convenience of the electrolytic tank are improved, the device is suitable for a hydrogen production environment with high precision requirements, and the sealing effect is avoided from being affected by gravity.

[0046] Embodiment 3, referring to Figures 3-8 , the third embodiment of the present application, which is different from the previous embodiment is the detection assembly 500, the detection assembly 500 includes a mounting seat 501 located on the fastening screw 402, the mounting seat 501 is provided with a force sensor 502 and a signal sensor 503, the side of the mounting seat 501 away from the end plate 300 is provided with a sliding sleeve 504 and a spring 505, and the side of the sliding sleeve 504 away from the mounting seat 501 is provided with a fastening nut 506.

[0047] Further, the spring 505 is located between the sliding sleeve 504 and the mounting seat 501, the sliding sleeve 504 and the mounting seat 501 are in sliding connection with the inner walls, the force sensor 502 is located between the mounting seat 501 and the spring 505, the spring 505 can automatically compensate when thermal expansion or pressure fluctuation occurs, the impact of mechanical stress on the sealing mechanism is reduced, the service life is prolonged, the sliding structure of the sliding sleeve 504 can cooperate with the fastening nut 506 to realize stable movement, the stress of the stacked insulating supports 401 is ensured to be uniform, and local deformation is prevented.

[0048] The force sensor 502 can monitor the clamping force in real time, the sealing mechanism can maintain the best clamping state in the running process, leakage or damage caused by overpressure due to loosening is avoided, the data feedback of the signal sensor 503 can be integrated into the control system to realize dynamic adjustment or early warning, the safety and automation level of the equipment are improved, the penetrating design of the fastening screw 402 can simplify the stacking process of the multi-layer bipolar plate 100, and the assembly efficiency is improved, and the mounting seat 501 and the fastening nut 506 are arranged to facilitate the adjustment of the pressure between the plurality of bipolar plates 100.

[0049] The remaining structures are the same as those in Embodiment 2.

[0050] In summary, the structure realizes precise control, dynamic adaptation and efficient maintenance of sealing clamping force through intelligent sensing, elastic buffering and modular design, is suitable for long-term high-pressure operation of alkaline hydrogen production electrolytic cells, and balances reliability and operation and maintenance convenience.

[0051] Importantly, it should be noted that the constructions and arrangements of the present application shown in the various different example embodiments are merely illustrative. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications can be made to the embodiments without materially departing from the novel teachings and advantages described in this application (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc. and the like). For example, elements shown as integrally formed can be constructed of multiple parts or elements, the position of elements can be reversed or otherwise varied, and the nature or number of discrete elements or positions can be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present application. The order or sequence of any process or method steps can be changed or re-sequenced without departing from the generality of the application. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions, and arrangement of the example embodiments without departing from the scope of the present application. Accordingly, the present application is not limited to the particular embodiments described but extends to the scope of the appended claims.

[0052] Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation can not be described (i.e., those unrelated to the best mode of practicing the application currently under consideration).

[0053] It should be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions can be made. Such development efforts might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

[0054] It should be noted that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application, and although the present application is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all should be included in the scope of the claims of the present application.

Claims

1. A sealing mechanism, characterized by: The application relates to a bipolar plate (100) and a sealing gasket (200) for sealing the gap between two adjacent bipolar plates (100). The cross-section thickness of the sealing ring (201) gradually decreases from the sealing gasket (200) to the outside. The angle between the first face (101a) and the second face (101b) is alpha, and the angle between the second face (101b) and the third face (101c) is beta. The angles alpha and beta satisfy 90 DEG >= alpha > 85 DEG > beta >= 60 DEG.

2. The sealing mechanism of claim 1, wherein: The distance between the first face (101a) and the surface of the bipolar plate (100) is Z1, the distance between the second face (101b) and the third face (101c) is Z2, and the diameter of the sealing ring (201) is Z3. The lengths of Z1, Z2 and Z3 satisfy Z2 > Z3 > Z1. The length between Z1 and Z2 satisfies Z2 = 2Z1.

3. The sealing mechanism of claim 1, wherein: The second face (101b) is arranged in parallel with the surface of the bipolar plate (100).

4. A sealing mechanism as claimed in claim 2 or 3, characterized in that: The first face (101a) and the surface of the bipolar plate (100), the first face (101a) and the second face (101b), the second face (101b) and the third face (101c), and the third face (101c) and the surface of the bipolar plate (100) are connected through arc faces (101d).

5. The sealing mechanism of claim 2 or 3, wherein: The outer wall of the sealing ring (201) is in abutment with the first face (101a), the second face (101b) and the third face (101c), and the outer wall of the sealing gasket (200) is in abutment with the outer wall of the bipolar plate (100).

6. The sealing mechanism of claim 1 or 2, wherein: The sealing ring (201) and the sealing gasket (200) are made of rubber and are integrally formed through injection molding.

7. An alkaline hydrogen production electrolyzer cell, such as the sealing mechanism according to any one of claims 1 to 6, comprising end plates (300) on both sides of the bipolar plate (100), characterized in that: Two end plates (300) are connected with the bipolar plate (100) through a connecting assembly (400), and detection assemblies (500) are arranged at the two ends of the connecting assembly (400). The connecting assembly (400) comprises insulating supports (401) arranged on the upper and lower sides of the bipolar plate (100), the insulating supports (401) are limited through fastening screws (402), and the detection assemblies (500) are arranged at the two ends of the fastening screws (402).

8. The alkaline hydrogen generating electrolyzer of claim 7, wherein: The insulating supports (401) are connected with the bipolar plate (100) through bolts, pin holes (403) and pin bodies (404) for positioning are arranged between the bipolar plate (100) and the insulating supports (401), and the insulating supports (401) are provided with outer holes (405) corresponding to the fastening screws (402). The insulating supports (401) are arranged in an arc shape and wrap the bipolar plate (100).

9. The alkaline hydrogen generating electrolyzer of claim 8, wherein: The detection assembly (500) comprises a mounting base (501) on the fastening screw (402), the mounting base (501) is provided with a force sensor (502) and a signal sensor (503), and the side, away from the end plate (300), of the mounting base (501) is provided with a sliding sleeve (504) and a spring (505); the side, away from the mounting base (501), of the sliding sleeve (504) is provided with a fastening nut (506).

10. The alkaline hydrogen generating electrolyzer of claim 9, wherein: The spring (505) is located between the sliding sleeve (504) and the mounting base (501), and the sliding sleeve (504) and the mounting base (501) are in sliding connection with the inner walls; the force sensor (502) is located between the mounting base (501) and the spring (505).

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