Pole frame assembly for electrolytic cell and electrolytic cell

Abstract

The application provides a polar frame assembly for an electrolytic cell and an electrolytic cell, the polar frame assembly comprising: a polar plate comprising two opposite surfaces, at least one surface of the polar plate being configured to form an electrolytic chamber together with a diaphragm; a polar frame located at the outer periphery of the polar plate, and the thickness of the polar frame being configured to be greater than the thickness of the polar plate, the polar frame being provided with at least two hole groups, each hole group comprising a first liquid inlet through hole and an exhaust through hole penetrating along the thickness of the polar frame; and an insulating functional coating formed on the inner wall surface of the first liquid inlet through hole, the surface resistivity of the insulating functional coating being configured to be 10 5 Ω / sq to 10 9 Ω / sq.

Description

Technical Field

[0001] At least one embodiment of the present invention relates to the field of water electrolysis for hydrogen production technology, and more particularly to an electrode frame assembly and an electrolyzer for use in an electrolyzer. Background Technology

[0002] Alkaline water electrolysis for hydrogen production has become the mainstream industrial technology for large-scale green hydrogen production. Currently, industrial-grade alkaline electrolyzers typically consist of dozens or even hundreds of electrolysis chambers stacked in series, with each chamber sharing a common electrolyte inlet channel. Due to the total potential difference of tens to hundreds of volts across the stack, formed by the superposition of voltages from each series-connected electrolysis chamber, this potential difference drives current through the electrolyte in the shared channel, forming a bypass current. This bypass current does not participate in the electrochemical generation process, directly leading to a decrease in Faraday current efficiency. Simultaneously, it induces electrochemical corrosion in the flow area, accelerating the corrosion of metal components such as manifolds and branch pipes, shortening equipment lifespan, and increasing maintenance costs. Summary of the Invention

[0003] To address at least one of the aforementioned and other technical problems in the related art, the present invention provides an electrode frame assembly and an electrolytic cell for use in an electrolytic cell, thereby effectively solving at least some of the aforementioned technical problems.

[0004] This invention provides an electrode frame assembly for an electrolytic cell, comprising: an electrode plate having two opposing surfaces, at least one surface of the electrode plate being used to enclose an electrolytic chamber with a diaphragm; an electrode frame located on the outer periphery of the electrode plate, wherein the thickness of the electrode frame is configured to be greater than the thickness of the electrode plate, the electrode frame having at least two sets of holes, each set of holes including a first liquid inlet hole and a vent hole extending along the thickness of the electrode frame; and an insulating functional coating formed on the inner wall surface of the first liquid inlet hole, wherein the surface resistivity of the insulating functional coating is configured to be 10. 5 Ω / sq up to 10 9 Ω / sq.

[0005] According to an embodiment of the present invention, the first liquid inlet hole is connected to the electrolysis chamber through a first branch pipe, and the first liquid inlet hole and the first branch pipe form a first distribution channel; the insulating functional coating is formed on the inner wall surface of the first liquid inlet hole; or, the insulating functional coating is formed on the inner wall surface of the first liquid inlet hole and the inner wall surface of the first branch pipe.

[0006] According to an embodiment of the present invention, the above-mentioned hole group further includes a second liquid inlet through hole, the second liquid inlet through hole being connected to the electrolysis chamber through a second branch pipe, the second liquid inlet through hole and the second branch pipe forming a second distribution channel; the above-mentioned insulating functional coating is formed on the inner wall surface of the second liquid inlet through hole; or, the above-mentioned insulating functional coating is formed on the inner wall surface of the second liquid inlet through hole and the inner wall surface of the second branch pipe.

[0007] According to an embodiment of the present invention, the exhaust port is connected to the electrolysis chamber via a third branch pipe; the insulating functional coating is formed on the inner wall surface of the exhaust port and / or the inner wall surface of the third branch pipe.

[0008] According to an embodiment of the present invention, the second branch pipe is provided with at least one groove structure; and / or, the third branch pipe is provided with at least two groove structures, and the at least two groove structures are arranged side by side at intervals along the extending direction of the exhaust hole.

[0009] According to an embodiment of the present invention, the insulating functional coating comprises: an alkali-resistant polymer matrix and a conductive filler; the conductive filler is dispersed in the alkali-resistant polymer matrix.

[0010] According to embodiments of the present invention, the alkali-resistant polymer matrix is ​​selected from perfluorinated C2 to C3. 12 Homopolymers or copolymers of alkenyl compounds, tetrafluoroethylene and perfluorinated C2 to C2 compounds 12 One or more copolymers of alkyl vinyl ethers.

[0011] According to embodiments of the present invention, the alkali-resistant polymer matrix is ​​selected from polytetrafluoroethylene, tetrafluoroethylene and perfluorinated C2 to C3. 12 At least one of the copolymers of alkyl vinyl ethers and copolymers of tetrafluoroethylene and hexafluoropropylene.

[0012] According to embodiments of the present invention, the conductive filler comprises a first carbon material, which accounts for 20% to 35% of the total weight of the insulating functional coating; or, the conductive filler comprises metallic nickel or a nickel-coated second carbon material, wherein the particle size of the metallic nickel is 1 μm to 50 μm, and the thickness of the nickel coating layer in the nickel-coated second carbon material is 0.5 μm to 5 μm, and the conductive filler accounts for 30% to 40% of the total weight of the insulating functional coating; or, the conductive filler comprises silicon carbide, wherein the particle size of the silicon carbide is 1 μm to 20 μm, and the silicon carbide accounts for 25% to 40% of the total weight of the insulating functional coating.

[0013] According to an embodiment of the present invention, the above-mentioned insulating functional coating is a single-layer structure; the thickness of the above-mentioned insulating functional coating is 80 μm to 250 μm.

[0014] According to an embodiment of the present invention, the insulating functional coating is a double-layer structure, comprising: a base coating layer formed on the surface of the electrode plate; and a top coating layer formed on the surface of the base coating layer; the base coating layer is an alkali-resistant polymer layer without conductive filler, and the thickness of the base coating layer is 30 μm to 50 μm; the top coating layer is a composite layer containing the alkali-resistant polymer matrix and the conductive filler dispersed in the alkali-resistant polymer matrix, and the thickness of the top coating layer is 50 μm to 200 μm.

[0015] According to an embodiment of the present invention, at least one baffle is provided in the first liquid inlet hole, and the baffle covers a portion of the first liquid inlet hole.

[0016] According to an embodiment of the present invention, the baffle extends along the height direction of the first liquid inlet hole, and both ends of the baffle along the width direction of the first liquid inlet hole are respectively connected to the inner wall of the first liquid inlet hole; the height of the baffle is configured to be 30% to 70% of the height of the first liquid inlet hole; and / or, the thickness of the baffle is configured to be 2 mm to 5 mm.

[0017] The present invention also provides an electrolytic cell, comprising: a plurality of electrode frame assemblies, wherein a plurality of electrode plates are stacked along the thickness direction; two end plates are respectively disposed at both ends of the stacked plurality of electrode frame assemblies; and a diaphragm is disposed between two adjacent electrode frame assemblies, wherein the diaphragm and the electrode plates of the adjacent electrode frame assemblies enclose an electrolytic chamber.

[0018] According to an embodiment of the present invention, the electrolytic cell includes an electrode frame assembly; the electrolytic cell further includes an electrolyte inlet and a distribution cavity, the electrolyte inlet being disposed on any one of the end plates, and the distribution cavity being disposed adjacent to the other end plate; the electrolyte inlet, the first liquid inlet hole of the electrode frame assembly, the distribution cavity, and the second liquid inlet hole of the electrode frame assembly are sequentially connected to form a liquid inlet path for the electrolyte to enter the electrolysis chamber; the insulating functional coating is also formed on the inner wall surface of the distribution cavity.

[0019] According to an embodiment of the present invention, the electrolytic cell includes an electrode frame assembly; the electrolytic cell further includes an electrolyte inlet and a distribution cavity, the electrolyte inlet and the distribution cavity are disposed in the middle of the electrolytic cell, the electrolyte inlet and the distribution cavity are connected, and the electrolyte inlet, the distribution cavity and the first liquid inlet hole are sequentially connected to form a liquid inlet path for the electrolyte to enter the electrolysis chamber; the insulating functional coating is also formed on the inner wall surface of the distribution cavity.

[0020] According to an embodiment of the present invention, the electrolytic cell includes the electrode frame assembly, and the baffles of two adjacent electrode frame assemblies are staggered.

[0021] Based on the electrode frame assembly and electrolytic cell provided by this invention, the first liquid inlet hole and the exhaust hole provided in the electrode frame constitute the flow channel structure of the electrolytic cell. An insulating functional coating is formed at least on the inner wall surface of the liquid inlet channel, and its surface resistivity is controlled at 10⁻⁶. 5 Ω / sq up to 10 9 Within the electrostatic dissipation range of Ω / sq, this insulating functional coating bonds directly to the metal substrate without requiring pre-reserved mounting slots or mating structures. Its impact on the original flow channel cross-sectional area is negligible, thus avoiding problems such as flow channel reduction and interface sealing failure caused by independent physical bushings.

[0022] Furthermore, this insulating functional coating achieves its effect by setting the surface resistivity to 10. 5 Ω / sq up to 10 9 Within the range of Ω / sq, the coating has at least two effects on the performance of the electrolyzer. Firstly, the coating, with its high resistivity, is placed in the feed channel through which a large number of conductive ions flow, creating additional resistance in this channel and thus suppressing the intensity of bypass current, thereby improving current efficiency. Secondly, the surface resistivity of the insulating functional coating is configured to be less than or equal to 10 Ω / sq. 9 The coating has a capacitance of Ω / sq, giving it a certain charge migration capability and electrostatic dissipation capability. The static charge generated under continuous electrolyte flushing can slowly leak through the coating to the grounded metal substrate, preventing the electrostatic potential from accumulating on the coating surface to the discharge threshold, thereby reducing the risk of electrostatic spark ignition in a hydrogen-oxygen mixed environment. Attached Figure Description

[0023] Figure 1 The schematic diagram illustrates a polar frame assembly according to an embodiment of the present invention, showing a complete set of holes;

[0024] Figure 2 This schematically illustrates the usage state of multiple pole frame components stacked along the thickness direction;

[0025] Figure 3 yes Figure 1 A partial enlarged view of the first liquid inlet port portion of the polar frame assembly shown;

[0026] Figure 4 yes Figure 1 A partial enlarged view of the vent hole portion of the pole frame assembly shown;

[0027] Figure 5 yes Figure 1 A partial enlarged view of the second liquid inlet port portion of the polar frame assembly shown;

[0028] Figure 6 This is a 3D view of another type of polar frame component;

[0029] Figure 7 yes Figure 6 The enlarged view of part A of the polar frame assembly shown illustrates the first liquid inlet and the first branch pipe.

[0030] Figure 8 The schematic diagram illustrates a layered structure of an insulating functional coating according to the present invention;

[0031] Figure 9 A schematic diagram of the layered structure of another insulating functional coating of the present invention is shown;

[0032] Figure 10 The first liquid inlet port with a baffle is schematically shown;

[0033] Figure 11 Schematic illustration as follows Figure 10 The diagram shows the usage state of multiple pole frame assemblies with baffles stacked along the thickness direction.

[0034] Figure 12 The schematic diagram shows a structural schematic of an electrolytic cell according to an embodiment of the present invention, with some pole frame components omitted;

[0035] Figure 13 yes Figure 12 A partial cross-sectional view of the electrode frame assembly with a distribution cavity in the electrolytic cell shown;

[0036] Figure 14 The schematic diagram shows the structure of an electrolytic cell according to another embodiment of the present invention, with some pole frame components omitted;

[0037] Figure 15 yes Figure 14 A partial cross-sectional view of the electrode frame assembly with a distribution cavity in the electrolytic cell shown.

[0038] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0039] 100. Electrode frame assembly; 110. Electrode plate; 111. Electrode frame; 120. Hole group; 121. First liquid inlet hole; 122. Second liquid inlet hole; 123. Exhaust hole; 124. Second branch pipe; 125. Third branch pipe; 126. First branch pipe; 130. Insulating functional coating; 131. Primer coating; 132. Topcoat coating; 140. Baffle; 150. Roughening layer; 160. Distribution chamber; 170. Electrolysis chamber;

[0040] 200, diaphragm; 300, cathode; 400, anode; 500, end plate; 600, electrolyte inlet; 700, electrolyte outlet; 800, annular electrode frame. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0042] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, operations, and / or components, but do not exclude the presence or addition of one or more other features, operations, or components.

[0043] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0044] When using expressions such as "at least one of A, B, and C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C. Similarly, when using expressions such as "at least one of A, B, or C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C.

[0045] To address the bypass current problem in existing technologies, many solutions involve adding independent insulating components within the common electrolyte channel, such as embedding insulating bushings or installing insulating cover assemblies. Other solutions employ plasma spraying to form an insulating ceramic coating on the electrode frame surface. The common idea behind these solutions is to introduce high-resistivity insulating materials into the electrolyte common channel to block the ion conduction pathway. However, while pursuing "maximum insulation" to suppress bypass current, these technologies have not adequately considered the potential risks of electrostatic accumulation and discharge caused by high-resistivity materials in a hydrogen-oxygen mixed environment. For example, pure polytetrafluoroethylene (also known as Teflon) has a surface resistivity greater than 10⁻⁶. 14 Ω / sq, being an insulating material, lacks the ability to dissipate static electricity. Under continuous scouring by the electrolyte, static charge will be generated and accumulated on the insulating surface. Since the minimum ignition energy of hydrogen is only about 0.017 mJ, electrostatic discharge could ignite the hydrogen, causing a serious safety accident. Furthermore, according to relevant anti-static standards, insulating materials used in flammable and explosive environments must undergo additional grounding or humidification measures, which are difficult to implement continuously under the operating conditions of an electrolytic cell.

[0046] This application proposes an electrode plate for an electrolytic cell. Figure 1 The schematic diagram illustrates an electrode plate according to an embodiment of the present invention, showing a complete set of holes. Figure 2 The diagram illustrates the usage state of multiple plates stacked along the thickness direction. Figure 3 yes Figure 1 A partial enlarged view of the first liquid inlet port portion of the polar frame assembly shown.

[0047] This invention provides a polar frame assembly 100, see reference. Figures 1 to 3 As shown, the device includes an electrode plate 110, an electrode frame 111, and an insulating functional coating 130. The electrode plate 110 has two opposing surfaces, at least one surface of which is used to enclose an electrolysis chamber with a diaphragm. The electrode frame 111 is located on the outer periphery of the electrode plate 110, and its thickness is configured to be greater than that of the electrode plate 110. The electrode frame 111 has at least two sets of holes 120, each set of holes 120 including a first liquid inlet hole 121 and a vent hole 123 extending along the thickness of the electrode frame 111. The insulating functional coating is formed on the inner wall surface of the first liquid inlet hole 121, and its surface resistivity is configured to be 10⁻⁶. 5 Ω / sq up to 10 9 Ω / sq.

[0048] In some illustrative embodiments, reference is made to Figure 1 As shown, the pole frame assembly 100 is generally, but not limited to, configured as a generally circular or rectangular plate-like structure, specifically including an inner pole plate 110 and a pole frame 111 surrounding the outer side of the pole plate 110. Figure 1 Taking the circular electrode plate 110 as an example, the electrode frame 111 is configured as a ring structure, surrounding the outer edge of the electrode plate 110 and integrally formed with it. Furthermore, the thickness of the electrode frame 111 is configured to be greater than the thickness of the electrode plate 110, allowing the electrode frame 111 to protrude from one or both sides of the electrode plate 110. In other words, the electrode frame 111 can be understood as forming a peripheral boss of the electrode frame assembly 100. When multiple electrode frame assemblies 100 are stacked along the thickness direction, adjacent electrode frame assemblies 100 are tightly abutted by the electrode frame 111, while a noticeable gap is formed between the electrode plates 110.

[0049] The electrode frame assembly 100 is made of, but is not limited to, nickel plate, stainless steel plate, cast iron metal plate, and other metal materials suitable for use as an electrode frame assembly. A diaphragm 200 is disposed between two adjacent electrode frame assemblies 100 and, together with the electrode plate 110, encloses a closed electrolytic chamber 170, within which the electrolytic reaction takes place. The first liquid inlet vent 121 and the exhaust vent 123 within the same orifice group 120 are respectively connected to the same electrolytic chamber. The diaphragm 200 includes, but is not limited to, polyphenylene sulfide (PPS) diaphragms, asbestos diaphragms, or other diaphragm materials commonly used in the art.

[0050] In applications where the electrode frame assembly 100 is used in an alkaline water electrolyzer, the two sides of the electrode frame assembly 100 form an anode side and a cathode side, respectively. The anode side can be understood as the side where the oxidation reaction occurs during electrolysis. It contains an anode 400 (electrode). Hydroxide ions in the electrolyte lose electrons on the anode side to generate oxygen and water, corresponding to the oxygen evolution reaction (4OH → O2 + 2H2O + 4e). - The product is oxygen; the cathode side can be understood as the side where the reduction reaction occurs, and it contains a cathode 300 (electrode). Water molecules gain electrons on the cathode side to generate hydrogen gas and hydroxide ions, which corresponds to the hydrogen evolution reaction (2H2O + 2e-). - →H2+2OH-), the product is hydrogen gas.

[0051] Furthermore, at least two hole groups 120 are provided within the pole frame 111 of the pole frame assembly 100 (for clarity of the illustration, ...). Figure 1 Only one complete orifice group 120 is shown, along with a second liquid inlet through-hole 122 in another orifice group 120, corresponding to the anode side and cathode side, respectively. Each orifice group 120 includes a first liquid inlet through-hole 121 and a vent through-hole 123 extending along the thickness direction of the electrode assembly 100. The two orifice groups 120 are independent of each other, with one orifice group 120 used to supply electrolyte to the anode-side electrode plate 110 and vent oxygen, and the other orifice group 120 used to supply electrolyte to the cathode-side electrode plate 110 and vent hydrogen.

[0052] In the application scenario where the aforementioned polar frame assembly 100 is used in an electrolytic cell, refer to... Figure 2 As shown, when multiple electrode frame assemblies 100 are stacked along the thickness direction, each first liquid inlet hole 121 is aligned and connected along the stacking direction to form a liquid inlet channel extending along the stacking direction. The first liquid inlet hole 121 serves as a liquid inlet for inputting electrolyte (such as electrolyte stored from an external electrolyte source) into the corresponding electrolysis chamber 170. Furthermore, each exhaust hole 123 is aligned and connected along the stacking direction to form an exhaust channel extending along the stacking direction.

[0053] Reference Figure 1As shown, the exhaust port 123 is disposed above the electrolysis chamber 170, indirectly communicating with the liquid inlet channel formed by the first liquid inlet port 121 (specifically described in the following embodiments), and is located downstream of the electrolysis chamber 170. The exhaust port 123 serves as an outlet for outputting oxygen (anode side) or hydrogen (cathode side), as well as a portion of the electrolyte mist. Based on this, an insulating functional coating 130 is formed on the inner wall surface of the first liquid inlet port 121, and the surface resistivity of this insulating functional coating 130 is configured to be greater than or equal to 10. 5 Ω / sq, and less than or equal to 10 9 Ω / sq.

[0054] In this implementation, since the insulating functional coating 130 is directly attached to and tightly bonded to the surface of the corresponding portion of the pole frame assembly 100, there is no need to reserve a mounting groove or mating structure. The impact on the original flow channel cross-sectional area is negligible, thus avoiding problems such as flow channel reduction and interface sealing failure caused by setting independent physical bushings in related technologies. Furthermore, this insulating functional coating 130 achieves this by setting a surface resistivity of 10... 5 Ω / sq up to 10 9 Within the range of Ω / sq, the insulating functional coating 130 has at least two effects on the performance of the electrolyzer. Firstly, the insulating functional coating 130 has high resistivity; being disposed in the inlet channel through which a large number of conductive ions flow, it can form additional resistance in this channel, thereby suppressing the intensity of bypass current generated by ions and improving current efficiency. Secondly, the surface resistivity of the insulating functional coating 130 is less than or equal to 10 Ω / sq. 9 The coating has a capacitance of Ω / sq, enabling it to transfer charge, i.e., dissipate static electricity, which helps reduce the possibility of local static electricity accumulation. Static charges generated under continuous electrolyte flushing can slowly leak through the coating to the grounded electrode assembly 100, preventing the electrostatic potential from accumulating on the coating surface to the discharge threshold, thereby reducing the risk of electrostatic spark ignition in a hydrogen-oxygen mixed environment.

[0055] According to an embodiment of the present invention, referring to... Figure 1 As shown, the vent hole 123 is connected to the electrolysis chamber via the third branch pipe 125. An insulating functional coating is also formed on the inner wall surface of the vent hole 123 and / or the inner wall surface of the third branch pipe 125.

[0056] According to an illustrative embodiment of the present invention, referring further... Figure 1As shown, the orifice group 120 also includes a second liquid inlet orifice 122, which is connected to the electrolysis chamber via a second branch pipe 124. The second liquid inlet orifice 122 and the second branch pipe 124 form a second distribution channel. An insulating functional coating 130 is also formed on the inner wall surface of the second liquid inlet orifice 122; or, the insulating functional coating 130 is formed on both the inner wall surface of the second liquid inlet orifice 122 and the inner wall surface of the second branch pipe 124.

[0057] Continuing with the application scenario of stacking multiple electrode frame components 100 to form an electrolytic cell, when multiple electrode frame components 100 are stacked along the thickness direction, each second liquid inlet through hole 122 is aligned and connected along the thickness direction to form a second distribution channel for distributing electrolyte to the electrolysis chamber. The second distribution channel is located in the electrolyte flow path formed by the liquid inlet channel and the exhaust channel.

[0058] By applying an insulating coating 130 to the inner walls of multiple flow channels, additional resistance can be simultaneously formed along multiple paths through which bypass current may flow, further blocking ion conduction pathways and thus more effectively suppressing the intensity of bypass current and improving the current efficiency of the electrolyzer. Simultaneously, the continuous and dense adhesion of the coating to the inner walls of each flow channel ensures that the electrolyte remains in contact with the coating as it flows through the aforementioned through-holes and branch pipes, thereby exerting electrostatic dissipation over a wider area and promptly leaking static charges generated by the scouring of the electrolyte and gas two-phase flow, reducing the risk of electrostatic spark ignition in the hydrogen-oxygen mixed environment. Furthermore, the insulating coating within multiple flow channels also prevents the scouring and corrosive effects of the electrolyte and / or gas on the flow channels.

[0059] In some illustrative embodiments, reference is made to Figure 2 As shown, the electrode plate 110 includes a first surface and a second surface opposite to each other, both of which are used to enclose the diaphragm 200 to form an electrolysis chamber. That is, the electrode frame 111, as an annular peripheral boss, protrudes from the first surface and the second surface of the electrode plate 110 respectively. In at least two sets of holes 120, the second liquid inlet hole 122 is connected to the electrolysis chamber on the corresponding surface through the second branch pipe 124, and the exhaust hole 123 is connected to the electrolysis chamber on the same corresponding surface through the third branch pipe 125.

[0060] In some illustrative embodiments, reference is made to Figure 2 As shown, in the double-sided structure of electrode 110, electrode 110 is along the thickness direction (e.g. Figure 2Electrolysis chambers on the anode side and cathode side are formed on both sides (shown in the left-right direction). Furthermore, the electrode frame 111 is provided with two sets of holes 120, corresponding to the anode side and cathode side respectively. Each set of holes 120 includes a first liquid inlet hole 121, a second liquid inlet hole 122, and an exhaust hole 123 extending along the thickness direction; that is, each hole penetrates the electrode frame 111. The two sets of holes 120 are independent of each other. Within the same set, the first liquid inlet hole 121, the second liquid inlet hole 122, and the exhaust hole 123 are sequentially connected along the liquid inlet path, while different sets of holes 120 (i.e., the set of holes 120 corresponding to the anode side and the set of holes 120 corresponding to the cathode side) are isolated from each other and not directly connected.

[0061] Based on this, the second liquid inlet hole 122 in each hole group 120 is connected to the corresponding electrolysis chamber 170 via a second branch pipe 124, for guiding the electrolyte input from the liquid inlet channel to the corresponding electrolysis chamber 170; the exhaust hole 123 is connected to the same corresponding electrolysis chamber 170 via a third branch pipe 125, for exhausting the gas generated in the electrolysis chamber 170 and at least a portion of the electrolyte mist. Thus, two surfaces of one electrode plate 110 can simultaneously participate in the construction of two adjacent electrolysis chambers 170, realizing the function of a bipolar electrode frame assembly. This helps to reduce the overall volume and stacking layer number of the electrolytic cell, and increase the gas production per unit volume of the electrolytic cell. It should be understood that the embodiments of the present invention are not limited thereto.

[0062] In other illustrative embodiments, the electrode frame 111 may have only one protrusion relative to the electrode plate 110 to form an annular peripheral boss that abuts against the diaphragm 200; the other side of the electrode frame 111 facing away from the diaphragm 200 is flush with the electrode plate 110. That is, the electrode plate 110 has only one side used to enclose the electrolysis chamber 170 with the diaphragm 200, while the other side is flush with the electrode frame 111, thus serving as a plane for contact with adjacent electrode frame assemblies 100 or end plates 500. Compared to the above double-sided structure, the single-sided electrode frame assembly 100 has a simpler manufacturing process and is suitable for applications with high end sealing requirements.

[0063] Furthermore, compared to the embodiment described above where the first liquid inlet hole 121, the second liquid inlet hole 122, and the exhaust hole 123 are sequentially connected, the present invention also provides another illustrative embodiment. Specifically, in this embodiment, each hole group 120 of the electrode frame assembly 100 may not have a second liquid inlet hole 122, but instead, a second branch pipe communicating with the electrolysis chamber 170 is directly provided in the first liquid inlet hole. That is, when multiple electrode frame assemblies 100 are stacked along the thickness direction, the first liquid inlet hole forms a liquid inlet channel while simultaneously distributing the electrolyte to the corresponding electrolysis chamber 170 through its respective second branch pipe.

[0064] Figure 4 yes Figure 1 A partially enlarged view of the second liquid inlet hole of the electrode plate shown. Figure 5 yes Figure 1 A partial enlarged view of the exhaust vent of the electrode plate shown.

[0065] In some illustrative embodiments, reference is made to Figure 3 and Figure 4 As shown, the first liquid inlet hole 121, the vent hole 123, and the second liquid inlet hole 122 can adopt an oblong hole structure (i.e., an elongated oval hole with a significant height and width, and a width greater than its height). Specifically, the oblong hole penetrates the pole frame 111 along the thickness direction of the pole frame assembly 100, and its cross-section can be formed into an elongated oval shape, having a predetermined height L1 and a predetermined width. When multiple pole frame assemblies 100 are stacked along the thickness direction, the first liquid inlet hole 121 of each pole frame assembly 100 is along the stacking direction (e.g., ...). Figure 2 The electrodes (as shown in the left-right direction) are aligned and connected to form a common channel extending along the stacking direction. This common channel is the inlet channel for the electrolyte to enter the electrolytic cell via an external liquid source, forming an inlet path that flows along the thickness direction of each electrode assembly 100. Similar to the first inlet through-hole 121, the second inlet through-holes 122 and vent through-holes 123 of the multiple electrode assemblies 100 are also aligned and connected along the stacking direction. The multiple second inlet through-holes 122 are located downstream of the inlet channel and are connected in series to form a manifold for distributing electrolyte to the corresponding electrolytic chamber; the multiple vent through-holes 123 correspondingly form an exhaust channel for outputting hydrogen or oxygen.

[0066] According to an embodiment of the present invention, referring to Figure 4 and Figure 5 As shown, the second branch pipe 124 and / or the third branch pipe 125 are configured with groove structures that are recessed into the surface of the pole frame assembly 100. Specifically, the second branch pipe 124 has at least one groove structure. And / or, the third branch pipe 125 has at least two groove structures, which are arranged side by side at intervals along the extension direction of the second liquid inlet hole 122.

[0067] In some illustrative embodiments, reference is made to Figure 4 and Figure 5As shown, the second branch pipe 124 and the third branch pipe 125 include, but are not limited to, groove structures configured to be recessed into the surface of the electrode frame 111. This groove structure can be understood as a channel-like channel extending inward along the surface of the electrode frame 111 (i.e., the same surface where the electrolysis chamber 170 is formed), with a cross-section that can be configured to be approximately U-shaped or rectangular. The bottom of the groove structure is lower than the surface of the electrode frame 111, and the sides are defined by the groove walls. Thus, when the electrolyte flows within the groove structure, it is constrained and guided by the groove walls, allowing it to flow accurately from the second inlet hole 122 to the electrode plate 110 (or from the electrode plate 110 to the exhaust hole 123). The aforementioned groove structure includes, but is not limited to, being directly formed on the surface of the electrode frame 111 by any method such as stamping, etching, or machining, forming an integrated structure with the electrode frame 111. This simplifies the assembly process and eliminates the risk of leakage at pipe joints.

[0068] In some illustrative embodiments, reference is made to Figure 4 As shown, the second branch pipe 124 is used to connect the second liquid inlet hole 122 to the electrolysis chamber 170, and it includes, but is not limited to, a groove structure. Specifically, one end of the groove structure is connected to the wall of the second liquid inlet hole 122, and the other end extends to the edge of the electrode plate 110 and communicates with the electrolysis chamber 170. After the electrolyte flows out of the second liquid inlet hole 122, it directly enters the groove structure of the second branch pipe 124, flows along the groove structure to the area of ​​the electrode plate 110, and then enters the electrolysis chamber 170 to participate in the reaction. Since the second branch pipe 124 only undertakes the unidirectional transport function of guiding the electrolyte from the second liquid inlet hole 122 to the electrolysis chamber 170, only one groove structure is needed to meet the liquid supply requirements, while maintaining a simple flow channel and low flow resistance. Of course, the groove structure formed by the second branch pipe 124 can also be 2, 3, 4, 5, or any other arbitrary number.

[0069] In some illustrative embodiments, reference is made to Figure 5 As shown, the third branch pipe 125 connects the electrode plate 110 to the exhaust port 123. Unlike the second branch pipe 124, the third branch pipe 125 functions to guide the gas-liquid mixture (i.e., a mixture of oxygen or hydrogen and electrolyte mist) generated in the electrolysis chamber 170 to the exhaust port 123. When the gas-liquid mixture flows through the third branch pipe 125, the gas and liquid exhibit a two-phase flow state within the groove. Because the gas has a lower density and higher flow velocity than the electrolyte, it is easy to form gas resistance or local accumulation within the flow channel, affecting the smoothness of liquid drainage. Therefore, the third branch pipe 125 can be configured with at least two groove structures, specifically as follows: Figure 5 The seven groove structures shown are arranged side-by-side at intervals along the extension direction of the exhaust port 123. Of course, the groove structure formed by the third branch pipe 125 can also be one, two, three, four, five, six, or any other arbitrary number.

[0070] In this implementation, the multiple groove structures of the third branch pipe 125 provide multiple parallel gas-liquid outlet channels, allowing the gas-liquid mixture to be diverted into multiple grooves when flowing out of the electrolysis chamber 170. This increases the flow cross-sectional area of ​​the gas-liquid mixture, reduces flow resistance, and facilitates the rapid detachment of gas from the surface of the electrolysis chamber 170. Furthermore, the multi-channel arrangement allows the gas and liquid to continuously disperse and redistribute during flow, reducing the chance of bubbles merging and growing within the flow channels, thereby improving gas-liquid separation efficiency and discharge smoothness. In addition, the multiple groove structures are arranged side-by-side at intervals, with adjacent grooves separated by partition walls formed from the material constituting the pole frame 111. These partition walls act as reinforcing ribs, enhancing the mechanical strength of the pole frame 111 in this area and preventing localized deformation under stacking and clamping forces.

[0071] Continue to refer to Figure 4 and Figure 5 As shown, the insulating functional coating 130 is formed on the inner wall surfaces of the second branch pipe 124 and the third branch pipe 125, that is, the bottom and both sides of the groove are covered by the coating. Furthermore, it is also formed on the inner wall surfaces of the second liquid inlet hole 122 and the exhaust hole 123. The insulating functional coating 130 is continuously and densely adhered between the inner wall surfaces of the groove and the holes, and is tightly bonded to the electrode frame 111, ensuring that the electrolyte is always in contact with the coating when flowing in the groove. This forms an effective resistance barrier along the path through which bypass current may flow, while simultaneously utilizing the electrostatic dissipation properties of the coating to promptly dissipate static charges generated by friction. It should be understood that the embodiments of the present invention are not limited thereto.

[0072] In addition to the open groove structure described above, the second branch pipe 124 and / or the third branch pipe 125 may also employ an inner tube structure that extends radially along the electrode frame 111. One end of this inner tube structure communicates with the exhaust port 123 or the second liquid inlet port 122, while the other end extends radially along the electrode frame assembly 100 to the portion of the electrode frame 111 located at the edge of the electrode plate 110. This also achieves the function of guiding the electrolyte and / or the generated gas.

[0073] Figure 6 This is a 3D view of another type of polar frame component. Figure 7 yes Figure 6 The enlarged view of part A of the polar frame assembly shown illustrates the first liquid inlet and the first branch pipe.

[0074] In other illustrative embodiments, the first liquid inlet 121 communicates with the electrolysis chamber 170 via a first branch pipe 126, and the first liquid inlet 121 and the first branch pipe 126 form a first distribution channel for distributing electrolyte to the electrolysis chamber 170. An insulating functional coating 130 is formed on the inner wall surface of the first liquid inlet 121; or, the insulating functional coating 130 is formed on both the inner wall surface of the first liquid inlet 121 and the inner wall surface of the first branch pipe 126.

[0075] Specifically, each group of holes in the electrode frame assembly 100 includes a first liquid inlet through-hole 121 extending along the thickness of the electrode frame. Each first liquid inlet through-hole 121 is directly connected to the electrolysis chamber 170 via a first branch pipe 126, bypassing the second liquid inlet through-hole 122. Thus, the first liquid inlet through-hole 121 and the first branch pipe 126 together form a first distribution channel for directly distributing external electrolyte to the electrolysis chamber 170. The first branch pipe 126 includes, but is not limited to, a groove structure similar to that of the second branch pipe 124 and the third branch pipe 125.

[0076] In this implementation, the first liquid inlet hole 121 not only serves as part of the liquid inlet channel, undertaking the longitudinal transport function of the electrolyte, but also guides the electrolyte directly to each electrolysis chamber 170 through the first branch pipe 126, thus combining the functions of liquid inlet and distribution. Compared to the embodiment that requires an additional independent second liquid inlet hole, this implementation integrates the liquid inlet and distribution functions into the same flow channel structure by directly setting the first branch pipe 126 on the first liquid inlet hole 121. It eliminates the need to first transport the electrolyte through the liquid inlet channel to the distribution chamber of the electrolytic cell, and then distribute it to each electrolysis chamber through the distribution channel. This simplifies the hole group design of the electrode frame assembly, reduces the number of openings on the electrode frame, and helps to reduce processing costs and improve the structural strength of the electrode frame.

[0077] The above-described embodiment, which connects the first liquid inlet hole 121 to the first branch pipe 126, is applicable, but is not limited to, to electrolytic cells with central liquid inlet. When multiple electrode frame assemblies are stacked along the thickness direction, the first liquid inlet holes 121 of each electrode frame assembly are aligned and connected along the stacking direction to form a liquid inlet channel extending along the stacking direction. After the electrolyte enters from the electrolyte inlet 600 located in the middle of the electrolytic cell, it first flows into the liquid inlet channel formed by the aligned and connected first liquid inlet holes 121, and then is guided to each electrolysis chamber 170 to participate in the electrolysis reaction via the corresponding first branch pipes 126 on each electrode frame assembly. Since the electrolyte flows simultaneously from the middle of the electrolytic cell to both ends, the liquid inlet path length of each electrolysis chamber 170 is approximately equal, which is beneficial to improving the uniformity of electrolyte distribution among the electrolysis chambers. The insulating functional coating 130 can be formed on the inner wall surface of the first liquid inlet hole 121, or it can be formed on both the inner wall surface of the first liquid inlet hole 121 and the inner wall surface of the first branch pipe 126, so as to form additional resistance in the ion conduction path of the bypass current, while utilizing the electrostatic dissipation capability of the coating to eliminate the risk of electrostatic accumulation and avoid the corrosive effect of the electrolyte.

[0078] Figure 8 The schematic diagram illustrates a layered structure of an insulating functional coating according to the present invention.

[0079] According to an illustrative embodiment of the present invention, referring to Figure 8 As shown, the insulating functional coating 130 has a single-layer structure. The thickness of the insulating functional coating 130 is 80 μm to 250 μm.

[0080] Figure 9 The schematic diagram illustrates a layered structure of another insulating functional coating of the present invention.

[0081] According to another illustrative embodiment of the present invention, referring to Figure 9 As shown, the insulating functional coating 130 has a two-layer structure, including a base coating 131 and a top coating 132. The base coating 131 is formed on the surface of the pole frame assembly 100. The top coating 132 is formed on the surface of the base coating 131. The base coating 131 is an alkali-resistant polymer layer without conductive fillers, and the thickness of the base coating 131 is 30 μm to 50 μm. The top coating 132 is a composite layer containing an alkali-resistant polymer matrix and conductive fillers dispersed in the alkali-resistant polymer matrix, and the thickness of the top coating 132 is 50 μm to 200 μm.

[0082] In some illustrative embodiments, reference is made to Figure 8 and Figure 9As shown, before preparing the insulating functional coating 130, the area on the pole frame assembly 100 to be coated can be surface-treated to form a roughening layer 150. Specifically, the roughening layer 150 can be a micro-rough structure formed on the surface of the pole frame assembly 100 by sandblasting, etching, or other mechanical roughening treatments. Its surface roughness Ra is not limited to, but can be configured to be about 5 μm, specifically 4 μm, 5 μm, 6 μm, and other arbitrary values. It should be noted that the roughening layer 150 itself is not an independent material layer, but a rough interface formed on the surface of the pole frame assembly 100 after physical or chemical modification. It is located between the main body of the pole frame assembly 100 and the insulating functional coating 130, and plays a transitional connection role. It is used to increase the contact area between the insulating functional coating 130 and the pole frame assembly 100, forming mechanical interlocking anchor points, thereby enhancing the adhesion between the coating and the substrate.

[0083] Based on this, the insulating functional coating 130 can be formed directly or indirectly on the roughening layer 150. Depending on different application requirements, the insulating functional coating 130 can adopt a single-layer structure or a double-layer structure.

[0084] In one illustrative embodiment, reference is made to... Figure 8 As shown, the insulating functional coating 130 is a single-layer structure. This single-layer structure is formed by directly spraying an alkali-resistant polymer composite coating containing conductive fillers onto the surface of the electrode frame assembly 100, which has been roughened by sandblasting and coated with a silane primer, and then curing it to form a single functional layer. The insulating functional coating 130 can be obtained by applying a liquid-dispersed coating or a powder coating suitable for spraying. When using a liquid-dispersed coating, a flash-drying treatment is performed after spraying to remove moisture or solvents; subsequently, a final heat treatment is performed before assembly into the electrolytic cell to allow the PFA to reach a molten and leveled state and fuse to form a continuous film layer; after heat treatment, controlled cooling is performed to solidify the molten PFA into a film. The conductive fillers in the composite coating are uniformly dispersed in the alkali-resistant polymer matrix. The thickness of the single-layer structure (e.g., Figure 8 The L3 shown is not limited to being configured from 80μm to 250μm, specifically 80μm, 100μm, 120μm, 140μm, 160μm, 180μm, 200μm, 220μm, 250μm and other arbitrary thickness values.

[0085] In this implementation method, the advantage of using a single-layer structure is that the process is simple, the preparation cycle is short, and the cost is low. It is suitable for application scenarios where the flow channel structure is relatively simple and the requirements for coating adhesion are relatively low.

[0086] In another illustrative embodiment, reference is made to... Figure 9As shown, the insulating functional coating 130 can also be configured as a two-layer structure, specifically including a base coating 131 and a top coating 132. The base coating 131 is formed on the surface of the pole frame assembly 100 (i.e., above the roughening layer 150), and the top coating 132 is formed on the surface of the base coating 131. Specifically, the base coating 131 is an alkali-resistant polymer layer without conductive fillers, and the thickness of the base coating 131 (e.g., ...) is... Figure 9 The L shown 31 The thickness of the substrate is not limited to, but can be configured to be 30 μm to 50 μm, specifically 30 μm, 40 μm, 50 μm, and other arbitrary thickness values. The base coating material 131 may comprise a composite of a perfluoroalkoxy polymer (PFA) and a polyamide-imide (PAI) as a liquid-dispersed base coating, wherein the mass ratio of PFA to PAI can be configured to be 1.5:1 to 2.4:1. In preparing the base coating 131, the liquid-dispersed base coating is sprayed onto the treated surface and flash-dried to remove moisture or solvent from the liquid carrier, thus initially applying the base coating 131 to the surface of the electrode assembly 100.

[0087] Furthermore, the topcoat 132 can be a composite layer containing an alkali-resistant polymer matrix and conductive fillers dispersed in the matrix, and the thickness of the topcoat 132 (e.g., Figure 9 The L shown 32 The conductive filler in the topcoat 132 is configured to be 50 μm to 200 μm and may be a composite of PFA with conductive fillers such as graphite powder, nickel powder, or silicon carbide powder. The conductive filler in the topcoat 132 is uniformly distributed in the polymer matrix, and its content and type are adjusted according to the desired surface resistivity. During the preparation of the topcoat 132, the coating of the topcoat 132 is sprayed onto the surface of the flash-dried or pre-treated basecoat 131 and flash-dried again. Before electrolytic cell assembly, the basecoat 131 and topcoat 132 undergo final heat treatment to achieve a molten and leveled state, and to fuse the PFA in the two layers at the interface. Controlled cooling is then performed to form a continuous film layer of the topcoat 132.

[0088] In this implementation, the double-layer insulating functional coating 130 has superior technical advantages compared to a single-layer structure. First, the base coating 131, being a pure polymer layer without conductive fillers, directly contacts the electrode frame assembly 100, forming a denser and more complete insulating barrier. This effectively avoids pinhole defects or localized leakage channels caused by uneven distribution of conductive fillers at the interface. Second, the base coating 131 and the electrode frame assembly 100 achieve high bonding strength through the mechanical interlocking of the roughening layer 150 and the chemical bonding of the PFA / PAI interpenetrating network structure, achieving an adhesion level of Class 1 in the cross-cut adhesion test. Third, both the base coating 131 and the top coating 132 are based on PFA, sharing the same coefficient of thermal expansion. This ensures good interfacial compatibility under the thermal cycling conditions of frequent start-stop electrolytic cells, preventing delamination or peeling due to thermal stress. Finally, the base coating 131, as a dense polymer layer without fillers, effectively prevents ions in the electrolyte from penetrating into the electrode frame assembly 100, further enhancing the long-term insulation stability and alkali corrosion resistance of the coating. The topcoat 132 is responsible for providing electrostatic dissipation, and its surface resistivity is precisely controlled at 10 by the type and content of conductive fillers. 5 Ω / sq up to 10 9 Within the range of Ω / sq.

[0089] In general, regardless of whether a single-layer or double-layer structure is adopted, the total thickness of the insulating functional coating 130 must take into account insulation performance, flow channel unobstructedness, and process feasibility. If the total thickness of the insulating functional coating 130 is too thin (e.g., less than 80 μm), it is difficult to form a continuous and dense cover layer, which is prone to pinhole defects and leads to local leakage. If the total thickness of the coating is too thick (e.g., greater than 250 μm), it may reduce the cross-sectional area of ​​the flow channel, increase flow resistance, and increase the risk of coating cracking and peeling.

[0090] According to an embodiment of the present invention, the insulating functional coating 130 includes an alkali-resistant polymer matrix and a conductive filler. The conductive filler is dispersed in the alkali-resistant polymer matrix.

[0091] According to embodiments of the present invention, the alkali-resistant polymer matrix is ​​selected from perfluorinated C2 to C3. 12 Homopolymers or copolymers of alkenyl compounds, tetrafluoroethylene and perfluorinated C2 to C2 compounds 12 One or more copolymers of alkyl vinyl ethers.

[0092] According to embodiments of the present invention, the alkali-resistant polymer matrix is ​​selected from polytetrafluoroethylene, tetrafluoroethylene and perfluorinated C2 to C3. 12 At least one of the copolymers of alkyl vinyl ethers and copolymers of tetrafluoroethylene and hexafluoropropylene.

[0093] According to embodiments of the present invention, the conductive filler comprises a first carbon material, which accounts for 20% to 35% of the total weight of the insulating functional coating 130. Alternatively, the conductive filler comprises metallic nickel or a nickel-coated second carbon material, wherein the particle size of the metallic nickel is 1 μm to 50 μm, and the thickness of the nickel coating layer in the nickel-coated second carbon material is 0.5 μm to 5 μm, and the conductive filler accounts for 30% to 40% of the total weight of the insulating functional coating 130. Alternatively, the conductive filler comprises silicon carbide, wherein the particle size of the silicon carbide is 1 μm to 20 μm, and the silicon carbide accounts for 25% to 40% of the total weight of the insulating functional coating 130.

[0094] In some illustrative embodiments, the insulating functional coating 130 includes an alkali-resistant polymer matrix and a conductive filler dispersed in the alkali-resistant polymer matrix. The alkali-resistant polymer matrix is ​​selected from at least one of polytetrafluoroethylene (PTFE), copolymers of tetrafluoroethylene and perfluorinated C2 to C12 alkyl vinyl ethers (i.e., perfluoroalkoxy polymers, PFA), and copolymers of tetrafluoroethylene and hexafluoropropylene (i.e., perfluoroethylene propylene, FEP). The conductive filler is used to adjust the surface resistivity of the coating so that it falls within the electrostatic dissipation range.

[0095] In one illustrative embodiment, the conductive filler includes a first carbon material, which may specifically be graphite powder or carbon fiber. When graphite powder is used, its particle size can be configured to be from 5 μm to 50 μm; when carbon fiber is used, its diameter can be configured to be from 7 μm to 12 μm and its length to be from 50 μm to 500 μm. The first carbon material accounts for 20% to 35% of the total weight of the insulating functional coating 130.

[0096] In another illustrative embodiment, the conductive filler comprises metallic nickel or a nickel-coated second carbon material (such as nickel-coated graphite powder). When metallic nickel is used, its particle size is 1 μm to 50 μm; when a nickel-coated second carbon material is used, the thickness of the nickel coating layer is 0.5 μm to 5 μm. The conductive filler accounts for 30% to 40% of the total weight of the insulating functional coating 130. When nickel powder is used as the conductive filler, a PFA composite coating containing nickel powder can be electrostatically sprayed onto the surface of the base coating 131, wherein the nickel powder accounts for 35% of the total weight of the composite coating, the nickel powder particle size can be configured to be 5 μm to 20 μm, and the thickness of the top coating 132 can be configured to be approximately 100 μm to 150 μm. Nickel has excellent chemical stability in 30% KOH solution and does not corrode or dissolve. The surface resistivity of the top coating 132 prepared by this formulation and process, measured using the ASTM D257 standard method, is approximately 3 × 10⁻⁶. 6 Ω / sq up to 1×10 7 Ω / sq, which is also within the electrostatic dissipation range.

[0097] In another illustrative embodiment, the conductive filler comprises silicon carbide (SiC) powder with a particle size of 1 μm to 20 μm, and the silicon carbide accounts for 25% to 40% of the total weight of the insulating functional coating 130. Silicon carbide is a covalent compound with extremely high chemical inertness and is stable in both strong acids and alkalis. A PFA composite coating containing SiC powder can be electrostatically sprayed onto the surface of the base coating 131, wherein the SiC powder accounts for 30% of the total weight of the composite coating, and the SiC powder particle size is 5 μm to 15 μm. The topcoat 132 has a thickness of approximately 100 μm to 150 μm. The topcoat 132 prepared using this formulation and process has a surface resistivity of approximately 1 × 10⁻⁶, measured using the ASTM D257 standard method. 6 Ω / sq up to 5×10 6 Ω / sq, which is also within the electrostatic dissipation range.

[0098] In this embodiment, by selecting the type, particle size, and content of the conductive filler, the surface resistivity of the insulating functional coating 130 can be precisely controlled at 10. 5 Ω / sq up to 10 9 Within the range of Ω / sq.

[0099] As another alternative implementation, the insulating functional coating 130 can also directly adopt the above-mentioned single-layer structure. This single-layer structure involves directly spraying a PFA composite coating containing graphite powder, nickel powder, or SiC powder onto the surface of the electrode frame assembly 100, which has been roughened by sandblasting and coated with a silane primer. The conductive filler accounts for 20% to 40% of the total weight of the composite coating, and the thickness of the single-layer coating is 80 μm to 250 μm. The single-layer structure process is simpler and suitable for applications with relatively low requirements for coating adhesion or simpler flow channel structures. The aforementioned silane primer mainly promotes interfacial adhesion, and its dry film thickness can be 0.1 μm to 5 μm, or even 0.5 μm to 2 μm. Since the silane primer is significantly thinner than the single-layer functional coating, it is not shown as a separate structural layer in the accompanying drawings.

[0100] Figure 10 The diagram schematically shows the first liquid inlet orifice with a baffle. Figure 11 Schematic illustration as follows Figure 10 The diagram shows the usage state of multiple electrode plates with baffles stacked along the thickness direction.

[0101] According to another embodiment of the present invention, referring to Figure 10 and Figure 11 As shown, at least one baffle 140 is provided inside the first liquid inlet hole 121, and the baffle 140 covers a part of the first liquid inlet hole 121.

[0102] Specifically, when multiple pole frame components 100 are stacked along the thickness direction, the baffles 140 of two adjacent pole frame components 100 are staggered, with the thickness direction of the pole frame component 100 as the projection direction, and the projection portions of the two adjacent baffles 140 overlap.

[0103] According to an embodiment of the present invention, referring to Figure 10 and Figure 11 As shown, the baffle 140 extends along the height direction of the first liquid inlet hole 121, and both ends of the baffle 140 along the width direction of the first liquid inlet hole 121 are respectively connected to the inner wall of the first liquid inlet hole 121. The height of the baffle 140 is configured to be 30% to 70% of the height of the first liquid inlet hole 121. And / or, the thickness of the baffle 140 is configured to be 2mm to 5mm. Here, "height direction" and "width direction" should be understood as two mutually perpendicular directions in a plane perpendicular to the stacking direction (i.e., the polar frame plane). "Height direction" can be understood as the direction of the minor axis of the oblong hole (i.e., the direction with the shorter length in the cross-section of the oblong hole, such as...). Figure 11 (As shown in the up and down directions), "width direction" can be understood as the direction of the major axis of the oblong hole (i.e., the direction with the longer length in the cross-section of the oblong hole, such as...). Figure 11 (The direction shown is towards the paper). When multiple pole frame assemblies are stacked along the thickness direction, each first liquid inlet hole is aligned and connected to form a common channel extending along the stacking direction. The extension direction of this common channel is perpendicular to both the height and width directions of the aforementioned waist-shaped hole. The baffle 140 can be integrally formed with the pole frame assembly 100 through processes such as stamping, and then the insulating functional coating 130 is formed on the surface of the baffle 140 through a spraying and curing process. Based on this, refer to Figure 10 and Figure 11 As shown, a baffle 140 is provided inside the first liquid inlet hole 121. This baffle 140 extends along the height direction of the first liquid inlet hole 121 (e.g., ...). Figure 11 Extending in the vertical direction (as shown), the baffle 140 is connected to the inner wall of the first liquid inlet hole 121 at both ends along the width direction of the first liquid inlet hole 121, thereby partially blocking the flow channel. Specifically, the height (L2) of the baffle 140 is, but is not limited to, configured to be 30% to 70% of the height (L1) of the first liquid inlet hole 121, for example, it can be 30%, 40%, 50%, 60%, 70%, and any other value between 30% and 70% of the height of the first liquid inlet hole 121. Further, the thickness of the baffle 140 is, but is not limited to, configured to be 2mm to 5mm, for example, it can be 2mm, 3mm, 4mm, 5mm, and any other value. The baffle 140 is, but is not limited to, integrally formed with the pole frame assembly 100 during the stamping process, without the need for additional independent components.

[0104] Continue to refer to Figure 11As shown, when multiple pole frame assemblies 100 are stacked along the thickness direction, the baffles 140 of two adjacent pole frame assemblies 100 are staggered along the height direction of the first liquid inlet hole 121. This staggered arrangement can be understood as the two baffles 140 being at different heights along the height direction of the first liquid inlet hole 121. For example, one baffle 140 is located at the bottom of one first liquid inlet hole 121, while the next baffle 140 is located at the top of the next first liquid inlet hole 121, thus causing the positions of the two baffles 140 in the height direction of the first liquid inlet hole 121 to be offset from each other. Furthermore, with the thickness direction of the pole frame assembly 100 as the projection direction, the projected portions of two adjacent baffles 140 coincide. Specifically, the heights of the baffles 140 on two adjacent pole frame assemblies 100 can be the same (e.g., both being 50% of the height of the first liquid inlet hole 121) or different (e.g., one is 30% and the other is 70%), as long as the projected portions of the adjacent baffles 140 coincide.

[0105] In this embodiment, because the baffles 140 of adjacent electrodes are misaligned and their projected portions overlap, the electrolyte cannot flow in a straight line through the inlet channel formed by the multiple first inlet holes 121. Instead, it is blocked by the baffles 140 and forced to deflect to one side to bypass the baffles 140. After entering the first inlet hole 121 of the next electrode frame assembly 100, it encounters baffles 140 at different positions and deflects to the other side again. This causes the electrolyte to flow in an S-shaped tortuous manner within the common channel (e.g., Figure 11 (As shown by the dashed line).

[0106] Compared to the straight channel without baffles 140, the tortuous flow inlet channel significantly increases the actual flow path length of the electrolyte. According to the principle of ionic conductivity, resistance is proportional to path length (R=ρ·L / A, where ρ represents the electrolyte resistivity, L represents the path length, and A represents the cross-sectional area). The increase in path length L directly increases the equivalent ionic resistance of the electrolyte within the shared channel. Since the bypass current must overcome greater resistance when flowing through this shared channel, its current intensity is effectively suppressed, thereby further reducing current losses that do not participate in the electrochemical generation process and improving the current efficiency of the electrolyzer.

[0107] To further quantitatively illustrate the impact of staggered baffle arrangement on the electrolyte flow path length, path growth calculations were performed based on a geometric model. Taking an inlet channel formed by stacked first inlet holes 121 with a height of 14 mm, a baffle height of 7 mm (rising from the bottom), a baffle thickness of 3 mm, and a flow direction width of 13.3 mm as an example, for the fluid (i.e., electrolyte) at height y ≤ 7 mm, the additional path length generated by bypassing the baffle is ΔL(y) = ([2×(7-y)]²+3²). The cross-section of the inlet channel formed by the first inlet orifice is weighted and averaged. The average additional fluid distance within the baffle range (0 to 7 mm) is approximately 7.90 mm, and the additional fluid distance above the baffle range (7 to 14 mm) is 0 mm. The overall average additional distance is approximately 3.95 mm. Therefore, the weighted average path length of the inlet channel is approximately 13.3 + 3.95 ≈ 17.25 mm, which is approximately 30% longer than the straight-through distance of 13.3 mm, i.e., the path length multiple is approximately 1.3 times. It should be understood that the embodiments of the present invention are not limited thereto.

[0108] In other illustrative embodiments, at least two baffles 140 may also be provided within the first liquid inlet orifice 121 of an electrode frame assembly 100, for example, two baffles 140. These two baffles 140 are spaced apart along the height direction of the first liquid inlet orifice 121 and are staggered relative to each other in the height direction. By providing multiple staggered baffles 140 within a single first liquid inlet orifice 121, the electrolyte must sequentially bypass multiple baffles 140 as it flows through the first liquid inlet orifice 121. This further increases the tortuosity of the flow path, extends the path length, and further increases the equivalent ion resistance, thereby more effectively suppressing bypass current.

[0109] Alternatively, in some other illustrative embodiments, baffles 140 may be provided only in some of the first liquid inlet holes 121. For example, in three stacked electrode frame assemblies 100, baffles 140 may be provided only in the first liquid inlet holes 121 of the first and last electrode frame assemblies 100, while the electrode frame assembly 100 in the middle may not be provided with baffles 140. This can still achieve the purpose of increasing the length of the electrolyte flow path.

[0110] In some other illustrative embodiments, when the orifice group 120 includes a first liquid inlet orifice 121 and a second liquid inlet orifice 122, in addition to providing a baffle 140 in the first liquid inlet orifice 121, a baffle 140 can also be provided in part or all of the second liquid inlet orifice 122 with the same structure as the baffle in the first liquid inlet orifice, to further improve the equivalent ion resistance of the liquid phase channel, reduce the bypass current, and improve the current efficiency.

[0111] Figure 12 The schematic diagram shows the structure of an electrolytic cell according to an embodiment of the present invention, with some electrode plates omitted.

[0112] The present invention also provides an electrolytic cell, with reference to Figure 12As shown, the electrolytic cell includes multiple electrode frame assemblies 100, two end plates 500, and a diaphragm 200. The multiple electrode frame assemblies 100 are stacked along their thickness direction. The two end plates 500 are respectively disposed at both ends of the stacked electrode frame assemblies 100. The diaphragm 200 is disposed between two adjacent electrode frame assemblies 100, and the diaphragm 200 and the electrode plates 110 of the adjacent electrode frame assemblies 100 enclose an electrolytic chamber 170. In addition, the electrolytic cell also includes a cathode 300 and an anode 400. The cathode 300 is disposed within one electrolytic chamber 170, and the anode 400 is disposed within an adjacent electrolytic chamber 170.

[0113] According to an embodiment of the present invention, the electrolytic cell further includes an electrolyte inlet 600 and a distribution cavity 160. The electrolyte inlet 600 is disposed on any one end plate 500, and the distribution cavity 160 is disposed adjacent to the other end plate 500. The electrolyte inlet 600, the first liquid inlet hole 121 of the electrode frame assembly, the distribution cavity 160, and the second liquid inlet hole 122 of the electrode frame assembly are sequentially connected to form a liquid inlet path for the electrolyte to enter the electrolysis chamber 170. An insulating functional coating 130 is also formed on the inner wall surface of the distribution cavity 160.

[0114] In some illustrative embodiments, the aforementioned electrolytic cell can specifically be an alkaline water electrolytic cell, which can inject alkaline electrolyte (such as KOH, NaOH, or a mixture of KOH and NaOH) into the inlet channel of the electrolytic cell via an end-feed method. Specifically, the electrolytic cell includes multiple of the aforementioned electrode frame assemblies 100, two end plates 500, a diaphragm 200, a cathode 300, and an anode 400. The multiple electrode frame assemblies 100 are stacked along the thickness direction, and the two end plates 500 are respectively disposed at both ends of the stacked multiple electrode frame assemblies 100. The electrode frame assemblies 100 are pressed between the two end plates 500 by fasteners such as tension screws to ensure the overall sealing and structural stability of the electrolytic cell. The diaphragm 200 is disposed between two adjacent electrode frame assemblies 100, and the diaphragm 200 and the electrode plates 110 of the adjacent electrode frame assemblies 100 together form a closed electrolysis chamber 170. The cathode 300 is disposed in one electrolysis chamber 170, and the anode 400 is disposed in another adjacent electrolysis chamber 170.

[0115] Based on the above-described end-entry electrolyte method, the electrolyte enters from the electrolyte inlet 600 at the end plate 500 located at one end of the stacking direction, and flows from one end to the other through the first inlet through-hole 121 of each electrode frame assembly 100, forming an inlet channel aligned and penetrating along the stacking direction. Along the path of the inlet channel, a distribution chamber 160 is provided near the end plate 500 at the other end of the stacking direction. The electrolyte is collected and thoroughly mixed in this distribution chamber 160 to homogenize the concentration and temperature. After homogenization, the electrolyte is guided to the corresponding electrode plate 110 (i.e., each electrolysis chamber 170) through the second inlet through-hole 122 and the second branch pipe 124 of each electrode frame assembly 100, respectively, where an electrolysis reaction occurs under the action of a DC electric field between the cathode 300 and the anode 400. A reduction reaction occurs on the cathode side, where water molecules gain electrons to generate hydrogen gas and hydroxide ions (2H2O + 2e-). - →H2 + 2OH-), the product is hydrogen gas; an oxidation reaction occurs on the anode side, where hydroxide ions lose electrons to produce oxygen and water (4OH- → O2 + 2H2O + 4e-). - The product is oxygen. The gas-liquid mixture produced by the reaction (i.e., a mixture of hydrogen or oxygen and the electrolyte carried by the gas) is discharged from the electrolytic cell through the third branch pipe 125 and the exhaust port 123 of each electrode frame assembly 100.

[0116] In the above embodiment, the insulating functional coating 130 is formed on the inner wall surface of at least one flow channel in the pole frame assembly and the inner wall surface of the distribution cavity 160, and is tightly bonded to the pole frame assembly 100. No pre-reserved mounting slots or mating structures are required, and the impact on the original flow channel cross-sectional area is negligible. This avoids problems such as flow channel reduction, complex assembly, and interface sealing failure caused by independent physical bushings. The surface resistivity of the insulating functional coating 130 is controlled at 10⁻⁶. 5 Ω / sq up to 10 9 Within the electrostatic dissipation range of Ω / sq, the coating creates additional resistance in the ion-conducting path of the bypass current, thereby suppressing the intensity of the bypass current and improving current efficiency. Furthermore, the distribution chamber 160, as a hub for electrolyte collection and mixing, has a large internal volume and high turbulence, making it a critical node for bypass current formation and electrostatic accumulation. By providing an insulating coating 130 on its inner wall, the bypass current can be blocked during the collection stage before the electrolyte enters each electrolysis chamber, further extending the equivalent resistance path of the ion-conducting path and thus more effectively suppressing the bypass current. Simultaneously, the coating allows the static charge generated by electrolyte flow and mixing within the distribution chamber to slowly leak through the coating to the grounded electrode assembly, preventing the electrostatic potential from accumulating on the coating surface to the discharge threshold, thereby reducing the risk of electrostatic spark ignition in a hydrogen-oxygen mixed environment.

[0117] Furthermore, when the electrolytic cell is configured with an electrode frame assembly 100 featuring baffles 140, the electrolyte can flow in an S-shaped tortuous manner within the common channel, significantly increasing the actual flow path length and further enhancing the equivalent ionic resistance of the bypass current path. This synergistic effect is achieved with the insulating functional coating 130. Both the insulating functional coating 130 and the baffles 140 can be integrally formed with the electrode frame assembly 100 through processes such as stamping, resulting in a high degree of structural integration. This avoids a series of problems caused by independent physical bushings and inserts, simplifying the manufacturing process, reducing maintenance costs, and improving the long-term reliability and safety of the electrolytic cell.

[0118] Figure 13 yes Figure 12 A partial cross-sectional view of the electrode plates with a distribution cavity in the electrolytic cell shown.

[0119] According to the electrolytic cell provided by the present invention, with reference to Figure 12 and Figure 13 As shown, the first liquid inlet holes 121 of each pole frame assembly 100 are aligned and connected along the stacking direction to form a liquid inlet channel extending along the stacking direction. At least one pole frame assembly 100 is provided with a distribution cavity 160, which is located in the liquid inlet path of the liquid inlet channel and communicates with the liquid inlet channel.

[0120] According to the electrolytic cell provided by the present invention, with reference to Figure 12 and Figure 13 As shown, the distribution cavity 160 is disposed between the end plate 500 and the pole frame assembly 100 adjacent to the end plate 500.

[0121] In the aforementioned electrolytic cell employing end-feed liquid, refer to Figure 12 As shown, the distribution cavity 160 is disposed between the end plate 500 (without the electrolyte inlet 600 and electrolyte outlet 700) and the adjacent pole frame assembly 100. (Refer to...) Figure 12 As indicated by the arrow, the electrolyte enters from the electrolyte inlet 600 at the end plate 500 located at one end of the stacking direction, flows through the first liquid inlet through-hole 121 of each electrode frame assembly 100 to form a liquid inlet channel aligned and connected along the stacking direction, and flows from one end to the other. When the electrolyte reaches the other end of the stacking direction, it first enters the distribution chamber 160.

[0122] Specifically, the aforementioned distribution chamber 160 is directly connected to the inlet channel, allowing the electrolyte in the inlet channel to flow into the distribution chamber 160; simultaneously, the second inlet through-hole 122 is connected to the distribution chamber 160. The distribution chamber 160 has a certain volume, where the electrolyte entering it gathers and mixes thoroughly, making the concentration and temperature of the electrolyte tend to be uniform. Subsequently, the uniformly mixed electrolyte is guided from the outlet side of the distribution chamber 160 through the second inlet through-hole 122 and the second branch pipe 124 of each electrode frame assembly 100 to the corresponding electrolysis chamber 170, that is, the part between each electrode plate 110 and the opposite diaphragm 200, to participate in the electrolysis reaction. Thus, the electrolyte sequentially passes through the first inlet through-hole 121 (i.e., the inlet channel), the distribution chamber 160, the second inlet through-hole 122, the second branch pipe 124, and the electrolysis chamber 170 in the electrolytic cell for electrolysis. In this way, through the gathering and mixing effect of the distribution chamber 160, the concentration and temperature of the electrolyte are more uniform before entering each electrolysis chamber 170, which helps to improve the uniformity of electrolyte distribution between each electrolysis chamber, thereby improving the consistency of the overall performance of the electrolytic cell.

[0123] To verify the technical effect of the electrolytic cell using the above-mentioned electrode plates, two comparative examples and Example 1 were set up, respectively corresponding to the following... Figure 12 The end-entry / exit operating conditions shown were compared and verified. Comparative Example 1 is the baseline scheme in related technologies that does not employ any suppression measures. The inner walls of the first liquid inlet, second liquid inlet, exhaust outlet, corresponding branch pipes, and distribution chamber forming the common channel are all exposed metal surfaces, without any insulating bushings, inserts, or insulating coatings, and without baffles. Comparative Example 2 is a scheme where only staggered baffles are installed in the first and second liquid inlet without any coating. A baffle is installed in the first liquid inlet in the common channel area, and the baffles of adjacent plates are staggered along the length of the connecting cavity to increase the electrolyte flow path length. However, the inner walls of the first liquid inlet, second liquid inlet, exhaust outlet, corresponding branch pipes, and distribution chamber are all exposed metal surfaces without any insulating coating.

[0124] Based on Comparative Example 2, Examples 1 and 2 further provide an insulating functional coating 130 on the inner wall surface of the first liquid inlet hole, the second liquid inlet hole, the exhaust hole, the corresponding branch pipe, and the distribution cavity. For specific setting conditions, please refer to Table 1.

[0125] The coating samples were prepared and tested under laboratory conditions, and the overall performance of the electrolytic cell was evaluated based on the test data. Following the aforementioned double-layer coating process, a PFA / graphite powder composite insulating functional coating sample was prepared as a representative test sample. The total thickness of the double-layer insulating functional coating was 250 μm, with the topcoat thickness being 200 μm. The graphite powder content of this insulating functional coating was 25%, and the surface resistivity was measured using the method specified in ASTM D257. The coating adhesion test (cross-cut test, GB / T9286) achieved Grade 1, indicating good adhesion between the coating and the electrode frame assembly. After immersion in a 30% KOH solution at 80℃ for 1000 hours, the surface resistivity change rate was less than 10%, indicating excellent alkali resistance stability of the coating. Based on the above measured resistivity data and combined with the electrolytic cell structural parameters, the current efficiency was systematically evaluated, and the results are summarized in Table 1.

[0126] Table 1. Current efficiency evaluation results under different surface resistivity.

[0127]

[0128] As can be seen from Table 1, when the surface resistivity of the insulating functional coating 130 increases from 10... 5 Ω / sq increased to 5×10 6 At Ω / sq, the current efficiency is improved (from 93.62% to 94.09%).

[0129] When the insulating functional coating 130 and the baffle 140 are used simultaneously, the current efficiency of the electrolyzer increases from 93.21% to over 93.62%. Therefore, the functional insulating coating and the baffles within the first and second liquid inlet orifices work together to reduce bypass current and improve current efficiency.

[0130] Figure 14 The schematic diagram shows the structure of an electrolytic cell according to another embodiment of the present invention, with some electrode plates omitted. Figure 15 yes Figure 14 A partial cross-sectional view of the electrode plates with a distribution cavity in the electrolytic cell shown.

[0131] According to another embodiment of the present invention, referring to Figure 14 and Figure 15 As shown, the electrolytic cell also includes an electrolyte inlet 600 and a distribution chamber 160. The electrolyte inlet 600 and the distribution chamber 160 are located in the middle of the electrolytic cell and are connected to each other. The electrolyte inlet 600, the distribution chamber 160, and the first liquid inlet through hole 121 are sequentially connected to form a liquid inlet path for the electrolyte to enter the electrolysis chamber. An insulating functional coating 130 is also formed on the inner wall surface of the distribution chamber.

[0132] In some illustrative embodiments, reference is made to Figure 14 and Figure 15 As shown, the electrolytic cell can also adopt a central liquid inlet method. The electrolytic cell includes multiple electrode frame assemblies 100, two end plates 500, a diaphragm 200, a cathode 300, and an anode 400. The multiple electrode frame assemblies 100 are stacked along the thickness direction. The two end plates 500 are respectively disposed at both ends of the stacked multiple electrode frame assemblies 100. The diaphragm 200 is disposed between two adjacent electrode frame assemblies 100 and surrounds the electrode plates 110 of the adjacent electrode frame assemblies 100 to form an electrolytic chamber 170. The cathode 300 is disposed in one electrolytic chamber 170, and the anode 400 is disposed in another adjacent electrolytic chamber 170.

[0133] Unlike the aforementioned end-feed method embodiments, in this embodiment, the electrolytic cell further includes an electrolyte inlet 600 and a distribution cavity 160. Both the electrolyte inlet 600 and the distribution cavity 160 are located in the middle of the electrolytic cell, and the electrolyte inlet 600 and the distribution cavity 160 are directly connected. Specifically, the distribution cavity 160 is located inside the electrode frame assembly 100 located in the middle of the electrolytic cell. The electrode frame assembly 100 located in the middle has a greater thickness than the electrode frame assemblies 100 located on both sides. Its middle part adopts a hollow design to form a sandwich structure, which is sealed by an annular electrode frame 800 to form the distribution cavity 160. The electrolyte inlet 600 and the electrolyte outlet 700 are both located on the annular electrode frame 800.

[0134] Based on this, the first liquid inlet holes 121 of each electrode frame assembly 100 are aligned and connected along the stacking direction to form a liquid inlet channel. The distribution cavity 160 is disposed on the path of the liquid inlet channel and is directly connected to the liquid inlet channel. Each first liquid inlet hole 121 of each electrode frame assembly 100 is directly connected to the electrolysis chamber 170 through a first branch pipe 126. The first liquid inlet hole 121 and the first branch pipe 126 together constitute a distribution channel for distributing electrolyte to the electrolysis chamber 170. Thus, the electrolyte inlet 600, the distribution cavity 160, the first liquid inlet hole 121 and the first branch pipe 126 are sequentially connected to form a complete liquid inlet path for the electrolyte to enter the electrolysis chamber.

[0135] When the electrolyte enters the distribution chamber 160 from the electrolyte inlet 600 on the annular electrode frame 800, it gathers and mixes thoroughly within the distribution chamber 160, which has a certain volume, making the concentration and temperature of the electrolyte more uniform. Subsequently, the uniformly mixed electrolyte flows from the distribution chamber 160 to both ends in the stacking direction, entering the inlet channel formed by the aligned and interconnected first liquid inlet holes 121 of each electrode frame assembly 100. Then, through the corresponding first branch pipes 126 on each electrode frame assembly 100, it is guided to the corresponding electrode plate 110, i.e., each electrolysis chamber 170, to participate in the electrolysis reaction. Thus, the electrolyte sequentially passes through the electrolyte inlet 600, distribution chamber 160, first liquid inlet hole 121 (inlet channel), first branch pipe 126, and electrolysis chamber 170 on the annular electrode frame 800 in the electrolytic cell for electrolysis.

[0136] In this implementation, the electrolyte flows simultaneously from the middle to both ends, effectively shortening the flow distance for the electrolyte to reach each electrolysis chamber 170. This results in a more uniform electrolyte distribution among the chambers, which is beneficial for improving the thermal field distribution of the electrolytic cell and the resistance uniformity of each chamber. Simultaneously, an insulating functional coating 130 is formed on the inner wall of the distribution cavity 160. The distribution cavity 160, as the hub for electrolyte collection and mixing, has a large internal volume and a high degree of electrolyte flow and turbulence, making it a key node for bypass current formation and electrostatic accumulation. By providing an insulating functional coating 130 on the inner wall of the distribution cavity 160, bypass current can be blocked during the accumulation stage before the electrolyte enters each electrolysis chamber, further extending the equivalent resistance path of the ion conduction pathway, thereby more effectively suppressing bypass current. Simultaneously, the static charge generated within the distribution cavity due to electrolyte flow and mixing can be promptly leaked to the grounded electrode assembly through the electrostatic dissipation performance of the coating, preventing the static potential from accumulating on the coating surface to the discharge threshold, further reducing the risk of electrostatic spark ignition in the hydrogen-oxygen mixed environment. It should also be noted that directional terms mentioned in the embodiments, such as "upper," "lower," "front," "rear," "left," and "right," are only for reference in the accompanying drawings and are not intended to limit the scope of protection of the present invention. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or configurations will be omitted where they may cause confusion in understanding the present invention.

[0137] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A pole frame assembly for an electrolytic cell, characterized in that, include: An electrode plate comprising two opposing sides, at least one side of the electrode plate being used to enclose an electrolysis chamber with a diaphragm; An electrode frame is located on the outer periphery of the electrode plate, and the thickness of the electrode frame is configured to be greater than the thickness of the electrode plate. The electrode frame is provided with at least two groups of holes, each group of holes including a first liquid inlet hole and a vent hole that extend along the thickness of the electrode frame. An insulating functional coating is formed on the inner wall surface of the first liquid inlet orifice, and the surface resistivity of the insulating functional coating is configured to be 10. 5 Ω / sq up to 10 9 Ω / sq.

2. The polar frame assembly according to claim 1, characterized in that, The first liquid inlet hole is connected to the electrolysis chamber through the first branch pipe, and the first liquid inlet hole and the first branch pipe form a first distribution channel; The insulating functional coating is formed on the inner wall surface of the first liquid inlet hole; Alternatively, the insulating coating may be formed on the inner wall surface of the first liquid inlet hole and the inner wall surface of the first branch pipe.

3. The pole frame assembly according to claim 1, characterized in that, The hole group also includes a second liquid inlet through hole, which is connected to the electrolysis chamber through a second branch pipe, and the second liquid inlet through hole and the second branch pipe form a second distribution channel; The insulating functional coating is formed on the inner wall surface of the second liquid inlet hole; Alternatively, the insulating functional coating may be formed on the inner wall surface of the second liquid inlet hole and the inner wall surface of the second branch pipe.

4. The pole frame assembly according to claim 3, characterized in that, The exhaust port is connected to the electrolysis chamber via a third branch pipe; The insulating coating is formed on the inner wall surface of the vent hole and / or the inner wall surface of the third branch pipe.

5. The pole frame assembly according to claim 4, characterized in that, The second branch pipe is provided with at least one groove structure; And / or, the third branch pipe is provided with at least two groove structures, and the at least two groove structures are arranged side by side at intervals along the extension direction of the exhaust hole.

6. The polar frame assembly according to any one of claims 1 to 5, characterized in that, The insulating functional coating includes: Alkali-resistant polymer matrix and conductive filler; The conductive filler is dispersed in the alkali-resistant polymer matrix.

7. The polar frame assembly according to claim 6, characterized in that, The alkali-resistant polymer matrix is ​​selected from perfluorinated C2 to C3. 12 Homopolymers or copolymers of alkenyl compounds, tetrafluoroethylene and perfluorinated C2 to C2 compounds 12 One or more copolymers of alkyl vinyl ethers.

8. The polar frame assembly according to claim 6, characterized in that, The alkali-resistant polymer matrix is ​​selected from polytetrafluoroethylene, tetrafluoroethylene and perfluorinated C2 to C1. 12 At least one of the copolymers of alkyl vinyl ethers and copolymers of tetrafluoroethylene and hexafluoropropylene.

9. The pole frame assembly according to claim 6, characterized in that, The conductive filler includes a first carbon material, which accounts for 20% to 35% of the total weight of the insulating functional coating. Alternatively, the conductive filler comprises metallic nickel or a nickel-coated second carbon material, wherein the particle size of the metallic nickel is 1 μm to 50 μm, the thickness of the nickel coating layer in the nickel-coated second carbon material is 0.5 μm to 5 μm, and the conductive filler accounts for 30% to 40% of the total weight of the insulating functional coating; Alternatively, the conductive filler may comprise silicon carbide with a particle size of 1 μm to 20 μm, and the silicon carbide may account for 25% to 40% of the total weight of the insulating functional coating.

10. The pole frame assembly according to any one of claims 1 to 5, characterized in that, The insulating functional coating has a single-layer structure; The thickness of the insulating functional coating is 80 μm to 250 μm.

11. The pole frame assembly according to any one of claims 1 to 5, characterized in that, The insulating functional coating has a double-layer structure, including: A base coating is formed on the surface of the electrode plate; A topcoat layer is formed on the surface of the basecoat layer; The base coating is an alkali-resistant polymer layer without conductive fillers, and the thickness of the base coating is 30 μm to 50 μm; The topcoat is a composite layer containing an alkali-resistant polymer matrix and the conductive filler dispersed in the alkali-resistant polymer matrix, and the thickness of the topcoat is 50 μm to 200 μm.

12. The pole frame assembly according to claim 1, characterized in that, At least one baffle is provided inside the first liquid inlet orifice, and the baffle covers a portion of the first liquid inlet orifice.

13. The pole frame assembly according to claim 12, characterized in that, The baffle extends along the height direction of the first liquid inlet hole, and both ends of the baffle along the width direction of the first liquid inlet hole are respectively connected to the inner wall of the first liquid inlet hole. The height of the baffle is configured to be 30% to 70% of the height of the first liquid inlet orifice; And / or, the thickness of the baffle is configured to be 2 mm to 5 mm.

14. An electrolytic cell, characterized in that, include: Multiple electrode frame assemblies as described in any one of claims 1 to 13, wherein the multiple electrode plates are stacked along the thickness direction; Two end plates are respectively disposed at both ends of the stacked plurality of polar frame assemblies; A diaphragm is disposed between two adjacent electrode frames, and the diaphragm and the electrode plates of the adjacent electrode frames form an electrolysis chamber.

15. The electrolytic cell according to claim 14, characterized in that, The electrolytic cell includes the electrode frame assembly as described in claim 3; The electrolytic cell further includes an electrolyte inlet and a distribution chamber. The electrolyte inlet is disposed on any one of the end plates, and the distribution chamber is disposed adjacent to the other end plate. The electrolyte inlet, the first liquid inlet hole of the electrode frame assembly, the distribution cavity, and the second liquid inlet hole of the electrode frame assembly are sequentially connected to form a liquid inlet path for the electrolyte to enter the electrolysis chamber; The insulating functional coating is also formed on the inner wall surface of the distribution cavity.

16. The electrolytic cell according to claim 15, characterized in that, The electrolytic cell includes the electrode frame assembly as described in claim 2; The electrolytic cell further includes an electrolyte inlet and a distribution cavity. The electrolyte inlet and the distribution cavity are located in the middle of the electrolytic cell. The electrolyte inlet and the distribution cavity are connected. The electrolyte inlet, the distribution cavity and the first liquid inlet hole of the electrode frame assembly are connected in sequence to form a liquid inlet path for the electrolyte to enter the electrolysis chamber. The insulating functional coating is also formed on the inner wall surface of the distribution cavity.

17. The electrolytic cell according to claim 14, characterized in that, The electrolytic cell includes the electrode frame assembly as described in claim 12, wherein the baffles of two adjacent electrode frame assemblies are staggered.

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