Bipolar plate, electrolytic bath and hydrogen production system

Abstract

The utility model discloses a bipolar plate, an electrolytic bath and a hydrogen production system. The bipolar plate comprises a bipolar plate body and an insulating layer, a through hole is formed in the bipolar plate body, and the through hole penetrates through the bipolar plate body in the thickness direction of the bipolar plate body; the insulating layer is arranged on the hole wall of the through hole, and the insulating layer is formed through at least one of the two modes of insulating film hot pressing and anodic oxidation. According to the bipolar plate, the insulating layers are arranged on the hole walls of the through holes and at least one side surface around the through holes, so that a medium circulating in the through holes can be isolated from the bipolar plate bodies, and the risk of short circuit among a plurality of bipolar plate bodies is reduced. The insulating layer is formed by using at least one of a hot pressing insulating film mode and an anodic oxidation mode, so that the insulating layer is easy to implement.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen production by water electrolysis, in particular to a bipolar plate, an electrolytic cell and a hydrogen production system. BACKGROUND

[0002] PEM electrolytic cells are commonly used for hydrogen production by water electrolysis. An electrolytic cell is the core structure of a PEM electrolytic cell, and the electrolytic cell is provided with a bipolar plate, a membrane electrode and the like. The bipolar plate is provided with a through hole, and the through hole is in direct contact with water. The bipolar plate also serves as an electrically conductive element in the electrolytic cell. If the water is contaminated and the electrical conductivity is increased, it may cause short circuits between multiple bipolar plates, which poses a risk to the operation of the electrolytic cell. CONTENT OF THE UTILITY MODEL

[0003] The present application aims to at least partially solve one of the above technical problems in the prior art. To this end, the present application provides a bipolar plate, which reduces the risk of short circuits between multiple bipolar plates.

[0004] The present application also provides an electrolytic cell having the bipolar plate.

[0005] The present application also provides a hydrogen production system having the electrolytic cell.

[0006] The bipolar plate according to an embodiment of the present application comprises a bipolar plate body and an insulation layer. The bipolar plate body is provided with a through hole, and the through hole penetrates the bipolar plate body along the thickness direction of the bipolar plate body. The insulation layer is arranged on the hole wall of the through hole, and the insulation layer is formed by at least one of a hot-pressed insulation film and an anodization.

[0007] The bipolar plate according to an embodiment of the present application can isolate the medium flowing in the through hole from the bipolar plate body by arranging the insulation layer on the hole wall of the through hole, thereby reducing the risk of short circuits between multiple bipolar plate bodies. The insulation layer is formed by at least one of a hot-pressed insulation film and an anodization, so that the insulation layer is easy to implement.

[0008] According to some embodiments of the present application, the bipolar plate body has two side surfaces arranged away from each other. The insulation layer comprises an inner ring segment and an outer extension segment. The inner ring segment is arranged on the hole wall of the through hole, and the outer extension segment is connected to the inner ring segment and arranged on the side surface.

[0009] According to some embodiments of the present application, the width of the outer extension segment extending radially outward from the inner ring segment is 0.2mm-5mm.

[0010] According to some embodiments of the present application, the insulating layer is an insulating layer formed by a hot-pressing insulating film method, when the insulating layer is formed by the hot-pressing insulating film method, the insulating film is wrapped on the hole wall of the through hole and the side surface around the through hole, and the insulating film is hot-pressed to form the insulating layer.

[0011] According to some embodiments of the present application, the thickness of the insulating layer is 0.05mm-0.5mm.

[0012] According to some embodiments of the present application, the insulating layer is an insulating layer formed by an anodization method, when the insulating layer is formed by the anodization method, the bipolar plate body is immersed in an electrolyte, a positive voltage is applied to the bipolar plate body, and the insulating layer is formed on the hole wall of the through hole and the side surface around the through hole.

[0013] According to some embodiments of the present application, the thickness of the insulating layer is 0.1μm-50μm.

[0014] The electrolytic cell according to the second aspect of the embodiments of the present application comprises the bipolar plate described above.

[0015] The electrolytic cell according to the embodiments of the present application can isolate the medium flowing in the through hole from the bipolar plate body by arranging the insulating layer on the hole wall of the through hole, thereby reducing the risk of short circuit between multiple bipolar plate bodies and reducing the operation risk of the electrolytic cell. The insulating layer formed by using at least one of the hot-pressing insulating film method and the anodization method makes the insulating layer easy to implement.

[0016] The hydrogen production system according to the third aspect of the embodiments of the present application comprises the electrolytic cell described above.

[0017] The hydrogen production system according to the embodiments of the present application can isolate the medium flowing in the through hole from the bipolar plate body by arranging the insulating layer on the hole wall of the through hole in the electrolytic cell of the hydrogen production system, thereby reducing the risk of short circuit between multiple bipolar plate bodies and reducing the operation risk of the electrolytic cell. The insulating layer formed by using at least one of the hot-pressing insulating film method and the anodization method makes the insulating layer easy to implement.

[0018] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a top view schematic diagram of a bipolar plate according to the embodiments of the present application;

[0020] Figure 2 is a sectional view schematic diagram of a bipolar plate according to the embodiments of the present application;

[0021] Figure 3 This is a cross-sectional schematic diagram of the bipolar plate body according to an embodiment of this application;

[0022] Figure 4 This is a side view of the stacked bipolar plate and membrane electrode according to an embodiment of this application;

[0023] Figure 5 This is a schematic diagram showing the positions of the through holes and sealing rings on the bipolar plate according to an embodiment of this application.

[0024] Figure label:

[0025] Bipolar plate 10, bipolar plate body 1, first side 11, second side 12, through hole 13, bipolar plate active area 14, insulating layer 2, inner ring segment 21, outer epitaxial segment 22, first outer epitaxial segment 221, second outer epitaxial segment 222, membrane electrode 20, membrane electrode through hole 201, sealing ring 30. Detailed Implementation

[0026] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0027] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] The following is combined Figures 1-5 The present application describes in detail a bipolar plate 10, an electrolyzer having the bipolar plate 10, and a hydrogen production system having the electrolyzer, according to embodiments of the present application.

[0029] Reference Figures 1-4 As shown, the bipolar plate 10 according to an embodiment of this application includes a bipolar plate body 1 and an insulating layer 2, wherein the insulating layer 2 is disposed on the bipolar plate body 1.

[0030] The bipolar plate body 1 has a through hole 13 that extends through the bipolar plate body 1 along its thickness direction. The bipolar plate body 1 has two sides facing away from each other. The bipolar plate body 1 has a sheet-like structure, and the sides are the largest surfaces. The through hole 13 extends from one side to the other, and is a through hole extending through the bipolar plate body 1 along its thickness direction.

[0031] An insulating layer 2 is disposed on the wall of the through hole 13. The insulating layer 2 is formed by at least one of two methods: hot pressing of an insulating film and anodizing. The hot pressing of an insulating film and anodizing are simple processes and easy to implement.

[0032] The through hole 13 allows the medium to flow through. The medium can be gas, liquid, or a gas-liquid mixture. The through hole 13 is in direct contact with the medium. The insulating layer 2 has good insulation properties and can isolate the medium flowing through the through hole 13 from the bipolar plate body 1, thus preventing short circuits between the bipolar plate body 1 and other bipolar plate bodies 1 when the medium is conductive.

[0033] For example, the through hole 13 is in direct contact with water. Even if the water becomes more conductive due to contamination, it will not cause a short circuit between the bipolar plates 10. When the bipolar plates 10 are used in an electrolytic cell, the operating risk of the electrolytic cell is reduced.

[0034] According to the embodiments of this application, the bipolar plate 10, by providing an insulating layer 2 on the wall of the through hole 13, can isolate the medium flowing in the through hole 13 from the bipolar plate body 1, reducing the risk of short circuits between multiple bipolar plate bodies 1 and improving the insulation performance of the system. The insulating layer 2, formed by using at least one of hot-pressing insulating film and anodizing, is easy to implement and form.

[0035] In some embodiments, refer to Figure 1 As shown, the bipolar plate body 1 is provided with a bipolar plate active region 14, and the through hole 13 is spaced apart from the bipolar plate active region 14.

[0036] In some embodiments, refer to Figure 1 As shown, the number of through holes 13 on the bipolar plate body 1 can be multiple, to allow different media to flow or to increase the amount of media.

[0037] In some embodiments, the insulating layer 2 is also disposed on at least one side around the through hole 13.

[0038] In some embodiments, refer to Figures 1-3As shown, the two side surfaces include a first side surface 11 and a second side surface 12, and the first side surface 11 and the second side surface 12 are both provided with the insulating layer 2. In other words, in the thickness direction of the bipolar plate body 1, the insulating layer 2 on the hole wall of the through hole 13 extends outward from both ends of the through hole 13 to the side surface. One end of the through hole 13 is the inflow position of the medium, and the other end of the through hole 13 is the outflow position of the medium. The insulating layer 2 extending outward from both ends of the through hole 13 to the side surface can isolate the medium from the side surface around the through hole 13 port, so that the medium does not come into contact with the bipolar plate body 1 when flowing into or flowing out of the through hole 13, thereby improving the insulation between the medium and the bipolar plate body 1, and further avoiding short circuit between the bipolar plate body 1 and other bipolar plate bodies 1.

[0039] In some embodiments, in combination with Figures 1-3 , the insulating layer 2 includes an inner ring segment 21 and an outer extension segment 22, the inner ring segment 21 is arranged on the hole wall of the through hole 13, and the outer extension segment 22 is connected with the inner ring segment 21 and arranged on the side surface. In other words, on the side surface of the bipolar plate body 1, the position surrounding the through hole 13 is the outer extension segment 22, and the outer extension segment 22 is attached to the side surface, which can insulate a circle around the through hole 13, so that the medium does not come into contact with the bipolar plate body 1 when flowing into or flowing out of the through hole 13, thereby avoiding short circuit between the bipolar plate body 1 and other bipolar plate bodies 1.

[0040] In some embodiments, the first side surface 11 and the second side surface 12 are both provided with the outer extension segment 22, which is specifically described in Figure 2 , the outer extension segment 22 includes a first outer extension segment 221 and a second outer extension segment 222, the first outer extension segment 221 is connected with one end of the inner ring segment 21, the second outer extension segment 222 is connected with the other end of the inner ring segment 21, the first outer extension segment 221 is arranged on the first side surface 11, and the second outer extension segment 222 is arranged on the second side surface 12.

[0041] In some embodiments, referring to Figure 2 As shown, the width of the outer extension segment 22 extending radially outward from the inner ring segment 21 is 0.2mm-5mm. The width of the outer extension segment 22 extending radially outward from the inner ring segment 21 is L, and 0.2mm≤L≤5mm. For example, L can be 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc., and can also be other values between 0.2mm and 5mm, which are not listed one by one here.

[0042] When L is less than 0.2 mm, the width of the outer extension 22 extending radially outward from the inner ring 21 is relatively narrow, resulting in poor insulation performance. When L is less than 5 mm, the width of the outer extension 22 extending radially outward from the inner ring 21 is too long, leading to material waste. By setting L to 0.2 mm ≤ L ≤ 5 mm, the outer extension 22 is made wider, achieving better insulation performance without excessive material waste.

[0043] In some embodiments, refer to Figure 2 As shown, the epitaxial segment 22 is a circular sheet structure with an outer diameter of d2 and a hole diameter of d1 for the through hole 13, where d2 > d1.

[0044] In some embodiments, the structures of the first extension segment 221 and the second extension segment 222 may be exactly the same or different.

[0045] In some embodiments, the insulating layer 2 is formed by at least one of three methods: spraying, hot-pressing insulating film, and anodizing. Spraying, hot-pressing insulating film, and anodizing are simple processes and easy to implement.

[0046] In some embodiments, the insulating layer 2 is an insulating layer 2 formed by spraying. When the insulating layer 2 is formed by spraying, the insulating layer 2 is sprayed onto the hole wall of the through hole 13 and the side surface around the through hole 13 by a spraying device.

[0047] In some embodiments, the spraying device can be a spray gun or a spraying machine, and the spraying parameters can be a spraying pressure of 0.2MPa to 1MPa, a spraying speed of 5mm / s to 10mm / s, and a spraying distance of 20mm to 150mm between the spraying device and the surface to be sprayed. After completing the side spraying around the through hole 13, the spray gun or spraying machine nozzle is tilted at 45° to spray the hole wall of the through hole 13.

[0048] In some embodiments, refer to Figure 2 As shown, when the insulating layer 2 is formed by spraying, its thickness is 0.5 μm to 100 μm. Specifically, the thickness of the insulating layer 2 is H, where 0.5 μm ≤ H ≤ 100 μm. For example, the thickness H of the insulating layer 2 can be 0.5 μm, 0.8 μm, 1 μm, 5 μm, 10 μm, 30 μm, 50 μm, 80 μm, 100 μm, etc., or other values ​​between 0.5 μm and 100 μm, which will not be listed here.

[0049] The insulating layer 2 formed by spraying can be relatively thin. When the thickness H of the insulating layer 2 is less than 0.5 μm, the insulating layer 2 is too thin, and its insulating effect is not obvious. When the thickness H of the insulating layer 2 is greater than 100 μm, the insulating layer 2 is too thick, resulting in waste of insulating material, increased cost, and increased overall weight of the bipolar plate 10. By setting the thickness of the insulating layer 2 to 0.5 μm to 100 μm, the insulating layer 2 can achieve a good insulating effect without excessive waste of insulating material, saving costs and not significantly increasing the weight of the bipolar plate 10.

[0050] In some embodiments, the insulating layer 2 comprises at least one component selected from acrylic resin, polyurethane, and silicone. For example, the insulating layer 2 comprises acrylic resin; or, the insulating layer 2 comprises polyurethane; or, the insulating layer 2 comprises silicone; or, the insulating layer 2 comprises acrylic resin and polyurethane; or, the insulating layer 2 comprises polyurethane and silicone; or, the insulating layer 2 comprises acrylic resin and silicone; or, the insulating layer 2 comprises acrylic resin, polyurethane, and silicone.

[0051] In some embodiments, the insulating layer 2 is an insulating layer 2 formed by hot pressing an insulating film. When the insulating layer 2 is formed by hot pressing an insulating film, the insulating film covers the hole wall of the through hole 13 and the side surface around the through hole 13, and the insulating film is hot pressed to form the insulating layer 2.

[0052] The hot-pressing insulating film process uses PET (Polyethylene glycol terephthalate) film or PEN (Polyethylene naphthalate) film. The thickness of the insulating film is 0.05mm to 0.5mm. After the bipolar plate body 1 and the insulating film are assembled, the combination of the bipolar plate body 1 and the insulating film is hot-pressed at 110℃ to 180℃ for 5min to 180min to form an insulating layer 2 on the bipolar plate body 1.

[0053] In some embodiments, refer to Figure 2 As shown, when the insulating layer 2 is formed by hot-pressing an insulating film, the thickness of the insulating layer 2 is 0.05mm to 0.5mm. Specifically, the thickness of the insulating layer 2 is H, where 0.05mm ≤ H ≤ 0.5mm. For example, the thickness H of the insulating layer 2 can be 0.05mm, 0.08mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc., or other values ​​between 0.05mm and 0.5mm, which will not be listed here.

[0054] When the thickness H of the insulation layer 2 is less than 0.05 mm, the insulation layer 2 is too thin, and its effect is not obvious. When the thickness H of the insulation layer 2 is greater than 0.5 mm, the insulation layer 2 is too thick, resulting in wasted insulation material, increased cost, and increased overall weight of the bipolar plate 10. By setting the thickness of the insulation layer 2 to 0.05 mm to 0.5 mm, the insulation layer 2 can provide good insulation without excessive waste of insulation material, saving costs and not significantly increasing the weight of the bipolar plate 10.

[0055] In some embodiments, the insulating layer 2 is an insulating layer 2 formed by anodizing. When the insulating layer 2 is formed by anodizing, the bipolar plate body 1 is immersed in the electrolyte and a positive voltage is applied to the bipolar plate body 1 to form the insulating layer 2 on the hole wall of the through hole 13 and the side surface around the through hole 13.

[0056] The anodizing process involves using an electrolyte with a conductivity of 1 μS / cm to 1 S / m. The electrolyte consists of common conductive solutions such as sulfuric acid, sodium hydroxide, phosphoric acid, sodium silicate, magnesium sulfate, and aqueous ethylene glycol solution. The solution temperature is 10℃ to 40℃. The area of ​​the bipolar plate body 1 with through holes 13 is immersed in the electrolyte, and a positive potential of 2V to 240V is applied. The oxidation is carried out for 1 min to 240 min to form an insulating layer 2 on the bipolar plate body 1.

[0057] In some embodiments, refer to Figure 2 As shown, when the insulating layer 2 is formed by anodizing, its thickness is 0.1 μm to 50 μm. Specifically, the thickness of the insulating layer 2 is H, where 0.1 μm ≤ H ≤ 50 μm. For example, the thickness H of the insulating layer 2 can be 0.1 μm, 0.8 μm, 1 μm, 20 μm, 30 μm, 40 μm, 50 μm, etc., or other values ​​between 0.1 μm and 50 μm, which will not be listed here.

[0058] The insulating layer 2 formed by anodizing is relatively thin. When the thickness H of the insulating layer 2 is less than 0.1 μm, it is too thin, and its insulating effect is not significant. When the thickness H of the insulating layer 2 is greater than 50 μm, it is too thick, leading to waste of insulating material, increased cost, and increased overall weight of the bipolar plate 10. By setting the thickness of the insulating layer 2 to be between 0.1 μm and 50 μm, it is possible to achieve good insulation performance without excessive waste of insulating material, thus saving costs and not significantly increasing the weight of the bipolar plate 10.

[0059] In some embodiments, the insulating layer 2 may also be an insulating layer 2 formed by a combination of two of the following three methods: spraying, hot pressing of an insulating film, and anodizing.

[0060] In some embodiments, the insulating layer 2 can also be formed by a combination of the three methods of spraying, hot-pressing an insulating film, and anodizing.

[0061] Six specific embodiments of processing the bipolar plate 10 of the present application are described below.

[0062] Embodiment 1

[0063] 1. Clean the surface of the bipolar plate body 1 using tap water and deionized water to remove surface impurities and dust; use adhesive tape to cover the non-sprayed areas;

[0064] 2. Use an insulating paint with acrylic resin as the main component, spray using nitrogen gas as the carrier gas, carrier gas pressure 0.5 MPa, spraying speed 5 mm / s, spraying distance 100 mm; after completing the single-sided spraying of the bipolar plate body 1, stand for 15 min until the insulating paint is dry, then turn over the bipolar plate body 1 to complete the spraying of the other side; then tilt the spray gun at 45° to complete the spraying of the hole wall of the through hole 13;

[0065] 3. Test the electrical conductivity of the sprayed area of the bipolar plate 10 using gold-plated copper electrodes, the surface resistivity is 87.4 Ω·cm when a pressure of 2 MPa is applied. 2 .

[0066] Embodiment 2

[0067] 1. Clean the surface of the bipolar plate body 1 using tap water and deionized water to remove surface impurities and dust;

[0068] 2. Use a 0.15 mm thick PET film, cut into a shape 5 mm longer than the edge of the insulating area of the bipolar plate 10, assemble with the hot-pressing tool and the bipolar plate body 1, and then place in a hot press at 170°C for 30 min; after hot pressing, the PET film is well combined with the bipolar plate body 1 without bubbles;

[0069] 3. Test the electrical conductivity of the area covered by the PET film of the bipolar plate 10 using gold-plated copper electrodes, the surface resistivity is 99.99 Ω·cm when a pressure of 2 MPa is applied. 2 .

[0070] Embodiment 3

[0071] 1. Clean the surface of the bipolar plate body 1 using tap water and deionized water to remove surface impurities and dust;

[0072] 2. Prepare a sulfuric acid aqueous solution with a conductivity of 10 μS / cm, maintain the solution temperature at room temperature, immerse the area of the bipolar plate body 1 provided with the through hole 13 in the sulfuric acid aqueous solution, use the bipolar plate body 1 as the anode, and a graphite counter electrode as the cathode, apply a positive potential of 100 V, and oxidize for 5 min;

[0073] 3. The conductivity of the oxidized region of the bipolar plate 10 was tested using a gold-plated copper electrode, and the surface resistivity was 51.8 Ω·cm when a pressure of 2 MPa was applied 2 .

[0074] Example 4

[0075] 1. The surface of the bipolar plate body 1 was cleaned using tap water and deionized water to remove surface impurities and dust;

[0076] 2. A magnesium sulfate aqueous solution having a conductivity of 0.1 S / m was prepared, the temperature of the solution was maintained at room temperature, the region of the bipolar plate body 1 provided with the through hole 13 was immersed in the sulfuric acid aqueous solution, the bipolar plate body 1 was used as the anode, a graphite counter electrode was used as the cathode, a positive potential of 20 V was applied, and oxidation was performed for 1 min;

[0077] 3. The conductivity of the oxidized region of the bipolar plate 10 was tested using a gold-plated copper electrode, and the surface resistivity was 17.4 Ω·cm when a pressure of 2 MPa was applied 2 .

[0078] Example 5

[0079] 1. The surface of the bipolar plate body 1 was cleaned using tap water and deionized water to remove surface impurities and dust;

[0080] 2. A glycol aqueous solution having a conductivity of 5 μS / cm was prepared, the temperature of the solution was maintained at room temperature, the region of the bipolar plate body 1 provided with the through hole 13 was immersed in the glycol aqueous solution, the bipolar plate body 1 was used as the anode, a graphite counter electrode was used as the cathode, a positive potential of 150 V was applied, and oxidation was performed for 6 min;

[0081] 3. The conductivity of the oxidized region of the bipolar plate 10 was tested using a gold-plated copper electrode, and the surface resistivity was 67.5 Ω·cm when a pressure of 2 MPa was applied 2 .

[0082] Example 6

[0083] 1. The surface of the bipolar plate body 1 was cleaned using tap water and deionized water to remove surface impurities and dust;

[0084] 2. A sulfuric acid aqueous solution having a conductivity of 5 μS / cm was prepared, the temperature of the solution was maintained at room temperature, the region of the bipolar plate body 1 provided with the through hole 13 was immersed in the sulfuric acid aqueous solution, the bipolar plate body 1 was used as the anode, a graphite counter electrode was used as the cathode, a positive potential of 10 V was applied, and oxidation was performed for 200 min;

[0085] 3. The conductivity of the oxidized region of the bipolar plate 10 was tested using a gold-plated copper electrode, and the surface resistivity was 32.8 Ω·cm when a pressure of 2 MPa was applied 2 .

[0086] The scheme in which no insulating layer 2 is set on the bipolar plate body 1 is taken as Comparative Example 1. Specifically, Comparative Example 1 is as follows:

[0087] 1. Clean the surface of the bipolar plate body 1 with tap water or deionized water to remove surface debris and dust;

[0088] 2. The conductivity of the area with through-hole 13 in the bipolar plate body 1 was tested using gold-plated copper electrodes. When a pressure of 2 MPa was applied, the surface resistivity was 0.137 mΩ / cm. 2 .

[0089] A higher surface resistivity indicates a lower short-circuit risk for the bipolar plate 10. In Examples 1 to 6, an insulating layer 2 is provided on the bipolar plate body 1; in Comparative Example 1, an insulating layer 2 is not provided on the bipolar plate body 1. As can be seen from Examples 1 to 6 and Comparative Example 1, the surface resistivity of the bipolar plate 10 with the insulating layer 2 on the bipolar plate body 1 is much greater than that of the bipolar plate 10 without the insulating layer 2. By providing an insulating layer 2 on the bipolar plate body 1, the short-circuit risk between multiple bipolar plate bodies 1 is greatly reduced.

[0090] Reference Figures 4-5 As shown, the electrolytic cell according to the second aspect of this application includes the bipolar plate 10 of the above embodiment.

[0091] In some embodiments, refer to Figure 4 As shown, the electrolytic cell also includes a membrane electrode 20, and a sealing ring 30 is provided between the membrane electrode 20 and the side of the bipolar plate 10. The sealing ring 30 surrounds the through hole 13, and the insulating layer 2 is located in the area surrounded by the sealing ring 30.

[0092] In some embodiments, refer to Figure 4 As shown, the membrane electrode 20 is provided with a membrane electrode through hole 201. The membrane electrode through hole 201 is a through hole that penetrates the membrane electrode 20 in the thickness direction of the bipolar plate body 1. The membrane electrode through hole 201 is connected to the corresponding through hole 13 so that the medium can flow through the through hole 13 and the membrane electrode through hole 201.

[0093] Reference Figure 4 As shown, one side of the sealing ring 30 is attached to the membrane electrode 20, and the other side of the sealing ring 30 is attached to the side of the bipolar plate 10. The sealing ring 30 can confine the medium between the membrane electrode 20 and the bipolar plate 10 within the space enclosed by the sealing ring 30, so that the medium can only flow through the through hole 13 and the membrane electrode through hole 201, and cannot flow to the area outside the sealing ring 30. This improves the insulation performance of the system, reduces the short circuit risk between multiple bipolar plate bodies 1, and reduces the operating risk of the electrolytic cell.

[0094] In some embodiments, combined with Figure 2 , Figures 4-5As shown, the sealing ring 30 is an annular sealing ring, which surrounds the through hole 13, and the outer extension 22 is located within the space surrounded by the sealing ring 30.

[0095] In some embodiments, refer to Figure 1 , Figures 4-5 As shown, there are multiple through holes 13 on the bipolar plate body 1, and the membrane electrode through holes 201 are connected to the through holes 13 one by one. Each through hole 13 is provided with a sealing ring 30 around its periphery.

[0096] According to the embodiments of this application, by providing an insulating layer 2 on the wall of the through hole 13, the medium flowing inside the through hole 13 can be isolated from the bipolar plate body 1, reducing the risk of short circuits between multiple bipolar plate bodies 1 and lowering the operational risk of the electrolytic cell. The insulating layer 2 is easy to implement by using at least one of the following methods: hot-pressing insulating film and anodizing.

[0097] The hydrogen production system according to a third aspect of this application includes the electrolyzer of the above-described embodiments.

[0098] According to the hydrogen production system of this application embodiment, the bipolar plate 10 of the electrolyzer has an insulating layer 2 provided on the wall of the through hole 13, which can isolate the medium flowing in the through hole 13 from the bipolar plate body 1, reduce the risk of short circuit between multiple bipolar plate bodies 1, and reduce the operational risk of the electrolyzer. The insulating layer 2 is easy to implement by using at least one of the two methods: hot pressing insulating film and anodizing.

[0099] In the description of this application, it should be understood that the terms "length", "width", "thickness", "upper", "lower", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0100] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0101] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate different embodiments or examples described in the specification.

[0102] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary, and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A bipolar plate (10) characterized by, Comprising: A bipolar plate body (1) provided with a through hole (13) penetrating the bipolar plate body (1) in a thickness direction of the bipolar plate body (1); An insulation layer (2) provided at least on a hole wall of the through hole (13), the insulation layer (2) being formed by at least one of a hot-pressing insulation film and an anodization.

2. The bipolar plate (10) according to claim 1, characterized in that The bipolar plate body (1) has two side surfaces arranged away from each other, and the insulation layer (2) comprises an inner ring segment (21) provided on the hole wall of the through hole (13) and an outer extension segment (22) connected with the inner ring segment (21) and provided on the side surface.

3. The bipolar plate (10) according to claim 2, characterized in that The outer extension segment (22) extends radially outward from the inner ring segment (21) by a width of 0.2mm-5mm.

4. The bipolar plate (10) according to claim 2 or 3, characterized in that The insulation layer (2) is formed by the hot-pressing insulation film, and when the insulation layer (2) is formed by the hot-pressing insulation film, the insulation film is wrapped on the hole wall of the through hole (13) and the side surface around the through hole (13), and the insulation film is hot-pressed to form the insulation layer (2).

5. The bipolar plate (10) according to claim 4, characterized in that The insulation layer (2) has a thickness of 0.05mm-0.5mm.

6. The bipolar plate (10) according to claim 2 or 3, characterized in that The insulation layer (2) is formed by the anodization, and when the insulation layer (2) is formed by the anodization, the bipolar plate body (1) is immersed in an electrolyte, and a positive voltage is applied to the bipolar plate body (1) to form the insulation layer (2) on the hole wall of the through hole (13) and the side surface around the through hole (13).

7. The bipolar plate (10) according to claim 6, characterized in that The insulation layer (2) has a thickness of 0.1μm-50μm.

8. An electrolytic cell characterized by, The bipolar plate (10) according to any one of claims 1-7.

9. A hydrogen production system, characterized by, The electrolytic cell according to claim 8.

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