Electrolytic device plates and electrolytic devices that use them

Abstract

The present invention discloses an electrolysis device electrode plate and an electrolysis device using the same, which converts electrical energy into chemical energy when connected to a DC power source and an electrolyte is injected into it. The electrode plate includes a silicon-based electrode plate made of a doped conductive silicon material. The silicon-based electrode plate is electrically connected to a DC power source and has a flow path on at least one surface thereof, so that the electrolyte is fed into the electrolysis device through the silicon-based electrode plate, causing an electrochemical reaction to occur and the reaction products to be discharged. The present invention significantly reduces the material and process costs of the electrolysis device electrode plate while maintaining good mechanical support and sealing function. At the same time, the overpotential for generating reaction products of the electrochemical reaction is reduced, and the electrolysis reaction rate per unit area in the electrolysis device is increased. This effectively reduces the operating voltage for the same electrochemical reaction rate, and ultimately significantly improves the energy conversion efficiency of the electrochemical reaction.

Description

[Technical Field]

[0001] This application claims priority from Chinese Patent Application No. 2023110128956, filed with the Patent Office of the State Intellectual Property Administration of the People's Republic of China on August 12, 2023, for an invention entitled "Electrode Plate for Electrolytic Device and Electrolytic Device Using the Same," the entire contents of which are incorporated herein by reference.

[0002] The present invention belongs to the field of electrolysis, and specifically relates to an electrode plate for an electrolysis device, and further relates to an electrolysis device to which the electrode plate is applied. [Background technology]

[0003] An electrolyzer is a device that converts electrical energy into chemical energy, and a typical example of an electrolyzer is a water electrolysis hydrogen generator. Hydrogen generation through water electrolysis is not only a mature technology, but also has no carbon emissions issues, making it an environmentally friendly and sustainable development route, making it the most important part of the current hydrogen energy development.

[0004] Specifically, the electrode plate is one of the important components of an electrolysis device (e.g., a water electrolysis hydrogen generation device), and mainly performs many functions, such as mechanical support for the main structure of the electrolysis device, sealing the body, conducting and distributing current, transporting and distributing reactants and products, and conducting and distributing heat and coolant (if any).

[0005] However, electrolysis devices, especially their anodes, operate in high-temperature and high-potential environments, placing increasing demands on the chemical stability of their materials. Currently, most electrolysis device electrodes are made of metals (such as titanium, nickel, and stainless steel), which have poor durability in electrochemical environments. To improve durability, expensive and difficult-to-process metals must be used, and expensive, complex precious metal protective films must be applied to the anode surface. Furthermore, existing electrolysis device electrodes are typically machined, resulting in poor precision in the size of the channel structures on the electrodes, which significantly impacts the mass transfer rate of reactants and products within the electrolysis device. Furthermore, the simple surface structure and relatively small area of ​​the electrodes impact the reaction rate per unit area within the electrolysis device. Currently, no research has been reported on the use of nonmetallic materials as electrodes in the field of purely electrolytic hydrogen generation.

[0006] Therefore, in this application, based on the tracking research of electrolysis equipment and the level of knowledge about silicon-based materials that the inventors' team has accumulated, we hope to seek technical solutions to solve the above technical problems. Summary of the Invention

[0007] In view of this, the object of the present invention is to provide an electrode plate for an electrolysis device and an electrolysis device using the same, which, while maintaining good mechanical support and sealing functions, significantly reduces the material cost of the electrode plate for the electrolysis device, and at the same time reduces the overpotential that generates reaction products of the electrochemical reaction, thereby increasing the electrolysis reaction rate per unit area in the electrolysis device, thereby effectively reducing the operating voltage for the same electrochemical reaction rate, and ultimately significantly improving the energy conversion efficiency of the electrochemical reaction.

[0008] The technical solutions used in the present invention are as follows:

[0009] 1. A plate for an electrolysis device that converts electrical energy into chemical energy when connected to a DC power source and filled with an electrolyte, the plate comprising a silicon-based plate made of a doped conductive silicon material, the silicon-based plate being electrically connected to a DC power source and having a flow path on at least one surface thereof, whereby the electrolyte is fed into the electrolysis device through the silicon-based plate, causing an electrochemical reaction to occur, and discharging reaction products.

[0010] Preferably, the resistivity of the silicon-based electrode plate is 0.1 Ω cm or less, preferably 1-30 mΩ cm, and / or the silicon-based electrode plate is made of a monocrystalline silicon or polycrystalline silicon material, preferably a monocrystalline silicon material, and / or the thickness of the silicon-based electrode plate is in the range of 0.1-10 mm, preferably 0.2-5 mm.

[0011] It should be noted that in the present application, silicon-based electrodes made using a crystalline silicon material (including single-crystalline silicon or polycrystalline silicon) have higher thermal conductivity than metals, and can therefore better conduct and distribute the heat generated in the electrochemical reaction of an electrolysis device using the silicon-based electrodes provided by the present application; the electrolysis device using the silicon-based electrodes provided by the present application will have higher temperature uniformity, reducing the impact of temperature non-uniformity on the performance and lifespan of the electrolysis device; the silicon-based electrodes not only enable the formation of fine flow path structures, but also enable the precise control of the consistency of the flow field structure and surface shape of the silicon-based electrodes; in subsequent applications, when multiple electrolysis units made from silicon-based electrodes are stacked to obtain a multi-layer electrolysis device, the performance of each electrolysis unit in the multi-layer electrolysis device will be more stable, which will better meet the application needs of increasing the number of electrolysis units in the multi-layer electrolysis device and further improve the performance and lifespan of the multi-layer electrolysis device.

[0012] Preferably, the flow path includes a channel structure consisting of staggered concave grooves and convex ridges, wherein the width of the concave grooves is 0.2 to 5 mm, preferably 0.5 to 1 mm, the width of the convex ridges is 0.1 to 10 mm, preferably 0.2 to 0.4 mm, and the height of the convex ridges is 0.1 to 5 mm, preferably 0.12 to 0.5 mm; and / or the flow path includes porous pores or a textured structure, wherein the diameter of the pores or the feature size of the textured structure is 0.1 μm to 1000 μm, preferably 0.3 μm to 10 μm.

[0013] Preferably, the channel structure is fabricated by an alkaline corrosion process or an electrochemical corrosion process, and the porous pore structure or textured structure is fabricated by a liquid phase method or a gas phase method, where preferably, liquid phase methods specifically include processes such as selective corrosion, electrochemical corrosion, and catalytic corrosion, and gas phase methods include processes such as plasma etching, all of which are well known. Various desired channel structures, porous pore structures, or textured structures can be fabricated according to actual application needs, and the effective contact area between the catalyst on the silicon-based electrode plate and the electrolyte can be increased while achieving the delivery of the electrolyte to the electrolysis device, thereby increasing the mass transfer rate of the reactants and reaction products in the electrochemical reaction and / or the reaction rate on the surface of the silicon-based electrode plate.

[0014] Preferably, at least a portion of the flow path is coated with a catalyst to promote the electrochemical reaction, and the catalyst may be a metal-based catalyst or a non-metal-based catalyst, preferably an iridium-based catalyst, a platinum-based catalyst, a nickel catalyst or a nickel alloy catalyst.

[0015] Preferably, the area ratio of the flow channels is in the range of 1.2 to 5, preferably 1.5 to 3, and more preferably 1.7 to 2. The area ratio referred to throughout this application refers to the ratio between the total surface area of ​​the flow channels exposed to the electrolyte (the area of ​​the corresponding electrode plate in contact with the electrolyte, i.e., the effective reaction area of ​​the electrode plate) and the area occupied by the surface of the flow channels in the electrolytic cell. Here, with regard to the "total surface area of ​​the flow channels exposed to the electrolyte" and the "area occupied by the surface of the flow channels in the electrolytic cell" according to this application, an SEM image can be obtained by performing an electron microscope scan of the electrode plate using a well-known scanning electron microscope (SEM). The electron microscope scan measures the surface area of ​​the flow channels exposed to the electrolyte and the area occupied by the surface of the flow channels in the electrolytic cell, and the area ratio of the flow channels can be obtained.

[0016] Preferably, the plates are bipolar plates, wherein: the silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port, and a cathode product discharge port; an anode flow path communicating with the anode product outlet is provided on one surface of the silicon-based electrode plate, and a cathode flow path communicating with the cathode product outlet is provided on the other surface of the silicon-based electrode plate; The electrolyte communication port communicates with the anode flow path and / or the cathode flow path.

[0017] Preferably, the plate is a bipolar plate, and the bipolar plate includes at least a first silicon-based plate and a second silicon-based plate stacked together, wherein: Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port, a cathode product discharge port, and a coolant communication port, an outer surface of the first silicon-based electrode plate is provided with an anode flow path communicating with the anode product outlet, and the second silicon-based electrode plate is provided with a cathode flow path communicating with the cathode product outlet; the electrolyte communication port communicates with the anode flow path and / or the cathode flow path; At the same time, a coolant flow path communicating with the coolant communication port is provided between the first silicon-based electrode plate and the second silicon-based electrode plate.

[0018] Preferably, the plate is an end anode plate or an end cathode plate, the end anode plate or end cathode plate comprising a silicon-based plate made of a doped conductive silicon material, wherein: the silicon-based electrode plate is provided with an electrolyte communication port, an anode product discharge port, or a cathode product discharge port; one surface of the silicon-based electrode plate is provided with an anode flow path communicating with the anode product outlet or a cathode flow path communicating with the cathode product outlet; The electrolyte communication port communicates with the anode flow path or the cathode flow path.

[0019] Preferably, the plate is an end anode plate or an end cathode plate, and the end anode plate or end cathode plate comprises at least a first silicon-based plate and a second silicon-based plate stacked together, and each silicon-based plate is made of a doped conductive silicon material, wherein: Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port or a cathode product discharge port, and a coolant communication port, an outer surface of the first silicon-based electrode plate or the second silicon-based electrode plate is provided with an anode flow path communicating with the anode product outlet or a cathode flow path communicating with the cathode product outlet; the electrolyte communication port communicates with the anode flow path or the cathode flow path; At the same time, a coolant flow path communicating with the coolant communication port is provided between the first silicon-based electrode plate and the second silicon-based electrode plate.

[0020] Preferably, the electrolysis device converts electrical energy into chemical energy when connected to a DC power source and an electrolyte is injected therein, and the electrode plates of the electrolysis device are as described above.

[0021] Preferably, the electrolyte is pure water, an alkaline aqueous solution, or an acidic aqueous solution, and generates hydrogen and oxygen by electrolyzing water through an electrochemical reaction.

[0022] Preferably, the electrolysis device comprises an anode current collector connected to the positive electrode of a DC power supply, a cathode current collector connected to the negative electrode of the DC power supply, an end anode plate connected in electrical contact with the anode current collector, and an end cathode plate connected in electrical contact with the cathode current collector, wherein a diaphragm or a proton exchange membrane, or one or more electrolysis units connected in series and / or parallel are provided between the end anode plate and the end cathode plate, and the single electrolysis unit comprises a bipolar plate and a diaphragm or a proton exchange membrane on both sides of the bipolar plate.

[0023] Preferably, the electrolysis devices are manufactured as standard products, connected in series and / or in parallel to a DC power supply, and assembled to obtain a desired electrolysis device module, wherein when the power supply from the DC power supply is insufficient to operate all of the electrolysis devices, the operation of some of the electrolysis devices is selectively stopped, allowing the remaining electrolysis devices to perform normal electrolysis operation.

[0024] Regarding the working principle and advantages of the present invention, before proposing the idea of ​​the present invention, the applicant found that in the prior art, metal material plates are usually used as the electrodes of water electrolysis devices to achieve good mechanical support and excellent current conduction, heat conduction and distribution, and distribution of reactants and products, etc. (especially, the use of carbon steel plates or titanium plates with a thickness of 2-5 mm is always preferred). The applicant also found that if silicon wafers are used to make the electrodes of silicon-based electrolysis devices, they can maintain good mechanical support and sealing functions, and that the abundance of silicon material resources and the maturity of silicon wafer processing technology make it possible to use silicon wafers. It has also been discovered that this significantly reduces the material and process costs of the plates of the electrolysis device. It is particularly noteworthy that the present application proposes electrically connecting the silicon-based plates to a DC power source and fabricating precise flow channels on the silicon-based plates to form precise and reliable flow field distributions, thereby improving the mass transfer rate of reactants and products in the electrolysis device and reducing the overpotential of the electrolysis reaction. Furthermore, by creating abundant surface topography on the silicon-based plates with flow fields, the contact area between the electrolyte and the plates can be effectively increased, thereby reducing the overpotential of the electrochemical reaction. This application reduces the overpotential of the electrochemical reaction from multiple aspects, thereby effectively reducing the operating voltage of the electrochemical reaction and ultimately significantly improving the energy conversion efficiency of the electrochemical reaction. Furthermore, compared to prior art metal-based electrodes, the present application significantly improves the uniformity of the operating temperature of the electrochemical reaction and the integrity of each unit in an electrolysis device consisting of multiple electrochemical reaction units, thereby further improving the electrolysis performance and lifespan of the electrolysis device. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a schematic diagram showing the structure of a bipolar plate according to Example 1 of the present invention; FIG. [Figure 2] FIG. 2 is a schematic diagram showing the structure of an end anode plate of Example 2 according to a specific embodiment of the present invention. [Figure 3]FIG. 10 is a schematic diagram showing the structure of an end cathode plate of Example 3 according to a specific embodiment of the present invention. [Figure 4] FIG. 10 is a schematic diagram showing the structure of a bipolar plate of Example 4 according to a specific embodiment of the present invention. [Figure 5] FIG. 10 is a schematic diagram showing the structure of an end anode plate of Example 5 according to a specific embodiment of the present invention. [Figure 6] FIG. 10 is a schematic diagram showing the structure of an end cathode plate of Example 6 according to a specific embodiment of the present invention. [Figure 7] FIG. 10 is a schematic diagram showing the structure of a bipolar plate of Example 7 according to a specific embodiment of the present invention. [Figure 8] FIG. 10 is a schematic diagram showing the structure of a bipolar plate of Example 9 according to a specific embodiment of the present invention. [Figure 9] FIG. 10 is a schematic diagram showing the structure of a bipolar plate according to a specific embodiment of the present invention. [Figure 10] FIG. 12 is a schematic diagram showing the plate mounting structure of the electrolysis apparatus of Example 14 based on a specific embodiment of the present invention. [Figure 11] FIG. 12 is a schematic diagram showing the mounting structure of the electrolysis apparatus of Example 14 based on a specific embodiment of the present invention. [Figure 12] FIG. 15 is a schematic diagram showing the plate mounting structure of the electrolysis apparatus of Example 15 based on a specific embodiment of the present invention. [Figure 13] FIG. 16 is a schematic diagram showing the mounting structure of the electrolysis apparatus of Example 16 based on a specific embodiment of the present invention. [Figure 14] 10 is an SEM photograph of a textured structure 13 on a silicon-based electrode plate of Example 7 according to a specific embodiment of the present invention. [Figure 15] 10 is another SEM photograph of the textured structure 13 on the silicon-based electrode plate of Example 7 according to a specific embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] An embodiment of the present invention discloses a plate for an electrolysis device, which converts electrical energy into chemical energy when connected to a DC power source and filled with an electrolyte, and the plate includes a silicon-based plate made of a doped conductive silicon material, wherein the silicon-based plate is electrically connected to the DC power source and has a flow path on at least one surface thereof (the flow path is for transporting and distributing the electrolyte or reaction products), so that the electrolyte is fed into the electrolysis device through the flow path on the silicon-based plate, allowing an electrochemical reaction to occur, and the reaction products are discharged.

[0027] Preferably, in this embodiment, the resistivity of the silicon-based electrode plate is 0.1 Ω·cm or less, preferably 1 to 30 mΩ·cm, more preferably 1 to 10 mΩ·cm, even more preferably 1 to 5 mΩ·cm, and even more preferably 1 to 3 mΩ·cm; and / or, preferably, in this embodiment, the silicon-based electrode plate is made of crystalline silicon (which may include crystalline types such as single crystal silicon or polycrystalline silicon, and may include doped types such as N-type doped crystalline silicon or P-type doped crystalline silicon), or an amorphous silicon material (including metallic silicon), preferably made of single crystal silicon material, and more preferably, the crystal direction is <111> Crystal directions other than the crystal direction, specifically: <100> Crystallographic direction, or <110> Crystallographic direction, or <111> crystallographic directions that make a clear angle with the crystallographic direction, most preferably <100> This is the crystal direction.

[0028] And / or, preferably, in this embodiment, the thickness of the silicon-based electrode plate is in the range of 0.1 to 10 mm, preferably 0.2 to 5 mm, more preferably 0.5 to 2 mm; and / or, preferably, in this embodiment, the shape of the silicon-based electrode plate may be rectangular, circular, or any other desired shape; this application is not limited to a specific embodiment. The substrate of the silicon-based electrode plate used in this application may be a silicon wafer obtained by cutting, and may further be chemically or mechanically polished to improve the surface flatness, thereby contributing to the processing efficiency of the silicon wafer in subsequent processes. When implementing this application, the thickness and shape of the silicon-based electrode plate can also be selected depending on the dynamic development level of the silicon wafer cutting and processing process; this application is not particularly limited within a single range. Preferably, in this embodiment, the flow path includes a channel structure composed of staggered concave grooves and convex ridges, wherein the width of the concave grooves is 0.2 to 5 mm, preferably 0.5 to 1 mm, the width of the convex ridges is 0.1 to 10 mm, preferably 0.2 to 0.4 mm, and the height of the convex ridges (i.e., corresponding to the depth of the concave grooves) is 0.1 to 5 mm, more preferably 0.1 to 2 mm, even more preferably 0.12 to 0.5 mm, and even more preferably 0.15 to 0.5 mm; and / or, preferably, in this embodiment, the flow path includes porous pores or texture. In practical implementation, the porous pores or textured structure may be formed independently on the silicon-based electrode plate, or in the case of a silicon-based electrode plate provided with a channel structure, the porous pores or textured structure may be further formed on the surface of the silicon-based electrode plate where the channel structure is located. Preferably, in this embodiment, the diameter of the porous pores or the feature size of the textured structure is 0.1 μm to 1000 μm, preferably 0.3 μm to 10 μm. In this way, in practical application, the electrolytic device can obtain an electrode plate with a fine flow field structure distribution and a surface shape with a high area ratio.

[0029] Preferably, in this embodiment, the channel structure is fabricated by an alkaline corrosion process or an electrochemical corrosion process. In practice, the alkaline corrosion process can be any known alkaline corrosion process or any known electrochemical corrosion process. More preferably, in this embodiment, for a silicon-based electrode plate made of N-type doped crystalline silicon, corrosion by a strong alkaline solution or electrochemical corrosion is recommended. For a silicon-based electrode plate made of P-type doped crystalline silicon, corrosion by an electrochemical process is recommended. Preferably, in this embodiment, the strong alkaline solution is organic or inorganic strong alkaline water. The solution can be selected. The mass concentration of the strong alkaline solution is recommended to be in the range of 10% to 50%, preferably a 25% to 35% KOH aqueous solution. The corrosion temperature is 50 to 120°C, preferably 70 to 85°C for the alkaline corrosion process. Of course, other methods can be used to fabricate the desired channel structure in this embodiment. Preferably, in this embodiment, the porous pore structure or textured structure is fabricated by a liquid-phase or vapor-phase method. Here, liquid-phase methods include processes such as selective corrosion, electrochemical corrosion, and catalytic corrosion, and vapor-phase methods include processes such as plasma etching. In specific implementations, any well-known silicon wafer texturing process (which belongs to the liquid-phase selective corrosion method) can be used to perform the surface texturing of the silicon-based electrode plate, and any well-known process (e.g., vapor-phase deposition) can be used to fabricate the porous silicon layer (i.e., the porous pore structure).The texturing process increases the area ratio of the silicon-based electrode plate, thereby increasing the electrochemical reaction rate per unit area of ​​the electrode plate surface in the electrolysis device, thereby not only improving the performance of the electrolysis device but also reducing the cost of the electrolysis device. When a porous silicon layer is fabricated on the silicon-based electrode plate, a porous pore structure that allows fluid to pass through is formed on the corresponding surface of the silicon-based electrode plate, which not only significantly increases the area ratio of the electrode plate but also improves the transport and flow efficiency of the electrolyte and reaction products (mainly gaseous) in the electrode plate flow channels, thereby increasing the electrochemical reaction rate per unit area of ​​the electrolysis device. The porous pore structure also reduces the hydrophobicity and aerobicity of the electrode plate, which suppresses the generation of large bubbles in the flow channels (including the exchange between reaction raw materials and reaction products in the flow channels, if any), thereby further improving the electrochemical reaction rate and energy conversion efficiency of the electrolysis device using it.

[0030] Preferably, in this embodiment, at least a part of the flow path (specifically, at least a part of the channel structure, or at least a part of the porous pore structure, or at least a part of the textured structure) is coated with a catalyst for promoting an electrochemical reaction, and the catalyst is a metal-based catalyst or a non-metal-based catalyst. Preferably, in this embodiment, the metal-based catalyst includes a noble metal-based catalyst and a non-noble metal-based catalyst, and the noble metal-based catalyst is selected from, for example, any one or more of Ir, Pt, Pd, Au, and Ag. The non-noble metal-based catalyst is selected from, for example, any one or more of Fe, Co, Ni, and Al. The non-metal-based catalyst is selected from, for example, a carbon material or a carbon composite material. As confirmed by the experiments of the present application, the silicon-based electrode plates can be matched with precious metal catalysts, such as Ir-Al alloys, and non-precious nickel-based catalysts (i.e., catalysts containing nickel (Ni), nickel catalysts, or nickel alloy catalysts). The nickel catalyst can be pure electrolytic nickel, while the nickel alloy catalyst can be high-activity nickel alloy catalysts, such as Raney nickel, activated nickel sulfide, Ni-Mo alloy, or activated NiAl. In practice, the appropriate catalyst should be selected according to specific cost and / or performance requirements, and is not limited to the present example. As confirmed by the experiments, when the electrode plates provided in the examples of the present application are provided with a catalyst layer, the need for a diffusion layer on the diaphragm or proton exchange membrane is eliminated in specific applications, further reducing structural costs.

[0031] In the practice of the present application, the catalyst can be coated using any known method, such as, but not limited to, spray coating, printing, electroplating, PVD, etc. Specifically, when the catalyst is directly coated onto the channel structure, electroplating, PVD, or other integral film-forming coating methods are recommended, and when the catalyst is coated onto the porous pore structure, physical coating methods such as spray coating, printing, etc. are recommended.

[0032] Preferably, in this embodiment, the area ratio of the flow channels is in the range of 1.2 to 5, more preferably 1.7 to 2. In practical application, not only can the overpotential required to generate an electrochemical reaction in an electrolytic device be significantly reduced, but the reaction rate per unit area can also be increased. It should be noted here that if a catalyst is coated on the flow channels in this embodiment, the activity of the catalyst can be further increased, which in turn can further reduce the overpotential required for the electrochemical reaction and increase the reaction rate per unit area in the electrolytic device.

[0033] It should be noted that the present application can respectively fabricate different bipolar plates, end anode plates or end cathode plates based on the plate solutions provided by the above embodiments according to the specific needs of the electrolysis device, and is not limited to only the present embodiment.

[0034] Preferably, this embodiment provides an electrolysis device that converts electrical energy into chemical energy when connected to a DC power source and an electrolyte is injected therein, and the electrodes of the electrolysis device use the above-described electrodes.

[0035] Preferably, in this embodiment, the electrolyte is pure water, an alkaline aqueous solution, or an acidic aqueous solution, and generates hydrogen and oxygen by electrolyzing water through an electrochemical reaction. Of course, it is also possible to select an appropriate electrolyte to produce the desired reaction product according to actual needs.

[0036] Preferably, in this embodiment, the electrolysis device comprises an anode end plate connected to the positive electrode of a DC power supply, a cathode end plate connected to the negative electrode of the DC power supply, an end anode plate connected in electrical contact with the anode end plate, and an end cathode plate connected in electrical contact with the cathode end plate, wherein a diaphragm or a proton exchange membrane, or one or more electrolysis units connected in series and / or parallel are provided between the end anode plate and the end cathode plate, and a single electrolysis unit comprises a bipolar plate and a diaphragm or a proton exchange membrane on both sides of the bipolar plate.

[0037] It should be further explained that in the present application, the electrode plate structure provided by the present embodiment can be applied to various types of electrolysis devices according to actual needs, including, but not limited to, alkaline electrolysis devices (also called alkaline electrolyzers) and PEM (proton exchange membrane) electrolysis devices (also called PEM electrolyzers), and of course, can also be applied to other types of electrolysis devices with similar needs, which are all common choices made by those skilled in the art based on the scope described in the present application, and will not be described again in the embodiments of the present application.

[0038] In order to more clearly describe the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings used in the description of the embodiments or the prior art. It should be understood that the drawings in the following description are only some embodiments described in the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative efforts.

[0039] Example 1: As shown in FIG. 1, a water electrolysis device plate, the plate being a bipolar plate, includes a silicon-based plate 10 made of a doped conductive silicon material, wherein: The silicon-based electrode plate 10 is provided with an electrolyte communication port, an anode product discharge port, and a cathode product discharge port, An anode flow path 11 communicating with an anode product outlet is provided on the lower surface of the silicon-based electrode plate 10, and a cathode flow path 12 communicating with a cathode product outlet is provided on the upper surface thereof. The electrolyte communication port communicates with the anode flow channel 11, and in another embodiment, as a second preferred example, it may communicate with the cathode flow channel 12, or it may communicate with both the anode flow channel 11 and the cathode flow channel 12.

[0040] In this embodiment, in actual production, the substrate of the silicon-based electrode plate 10 is specifically a 1.5 mm thick, circular, N-type doped single crystal silicon ( <100> A silicon wafer fabricated in the crystalline direction was selected, and its resistivity was 2.5 mΩ·cm.

[0041] A 30% mass concentration KOH aqueous solution is used to selectively etch the two surfaces of the silicon wafer to obtain a silicon-based electrode plate having channel structures on the upper and lower surfaces, respectively, where the channel structure on the upper surface of the silicon-based electrode plate 10 is the cathode flow channel 12 and the channel structure on the lower surface of the silicon-based electrode plate 10 is the anode flow channel 11.

[0042] In a specific implementation, the sizes of the channel structure of the cathode flow channel 12 and the channel structure of the anode flow channel 11 may be the same or different, and the channel structure in the same electrode flow channel (e.g., the anode flow channel 11, the cathode flow channel 12) may be configured so that wide channel units and narrow channel units are alternately arranged, thereby achieving better fluid transport efficiency, further improving the efficiency of the electrochemical reaction, and reducing the power consumption for driving the flow of reactants and products in the electrolysis device.

[0043] In this embodiment, the channel structure that becomes the anode flow channel 11 has grooves 11a that are 0.8 mm wide, groove depths of 0.2 mm, and protruding ridges 11b that are 0.4 mm wide. The channel structure that becomes the cathode flow channel 12 is similar to the channel structure that becomes the anode flow channel 11, with grooves 12a that are 0.8 mm wide, groove depths of 0.15 mm, and protruding ridges 12b that are 0.4 mm wide. The electrolyte communication port, anode product outlet, and cathode product outlet are fabricated in the silicon wafer by a laser process or other processes, and these two steps can be performed in any order depending on actual needs.

[0044] It should be noted that, to achieve the effect of communication between the electrolyte communication port, the anode product discharge port, and the cathode product discharge port and their corresponding flow paths, it is necessary to fabricate guide structures at appropriate positions on the outer periphery of the silicon wafer, and to introduce the electrolyte, the anode product, and the cathode product from the electrode plate flow field into the electrolytic device and discharge them from the electrolytic device, as will be obvious to those skilled in the art. Specifically, it is preferable to fabricate the channel structure and the guide structure at the same time, but this will not be described in detail in this example.

[0045] In this example, a single silicon wafer was used as the substrate for the silicon-based electrode plate 10, and when applied to a PEM water electrolysis device, there was no need to coat the silicon-based electrode plate with a thin film, and no changes in the electrical, mechanical, or chemical properties of the electrode plate were detected after long-term electrolysis hydrogen generation. In this example, to achieve a cooling effect by the electrolyte supplied directly to the anode flow path, it is recommended to set the electrolyte flow rate high, which results in the need to consume more power to drive the electrolyte.

[0046] Example 2: As shown in FIG. 2, a plate of an electrolysis device, the plate being an end anode plate, the end anode plate comprising a silicon-based plate 20 made of a doped conductive silicon material, wherein: The silicon-based electrode plate 20 is provided with an electrolyte communication port and an anode product discharge port, An anode flow path 21 communicating with the anode product outlet is provided on the underside of the silicon-based electrode plate 20, The electrolyte communication port communicates with the anode flow path 21 .

[0047] Other implementation means of the second embodiment are the same as those of the first embodiment.

[0048] Example 3: As shown in FIG. 3, a plate of an electrolytic device, preferably an end cathode plate, comprises a silicon-based plate 30 made of a doped conductive silicon material, wherein: The silicon-based electrode plate 30 is provided with an electrolyte communication port and a cathode product discharge port. A cathode flow path 31 communicating with the cathode product outlet is provided on the upper surface of the silicon-based electrode plate 30, Other implementation means of the third embodiment are the same as those of the first embodiment.

[0049] Example 4: As shown in FIG. 4, a plate of an electrolysis device, the plate being a bipolar plate, the bipolar plate including a first silicon-based plate 41 and a second silicon-based plate 42 stacked together, wherein: Each of the silicon-based electrodes 41 and 42 is provided with an electrolyte communication port, an anode product discharge port, a cathode product discharge port, and a coolant communication port, The first silicon-based electrode plate 41 has an outer surface provided with an anode flow path 41a communicating with an anode product outlet, and the second silicon-based electrode plate 42 has an outer surface provided with a cathode flow path 42a communicating with a cathode product outlet. The electrolyte communication port communicates with the anode flow path 41a, At the same time, a coolant flow path 43 communicating with the coolant communication port is provided between the first silicon-based electrode plate 41 and the second silicon-based electrode plate 42 .

[0050] Other implementation means of this Example 4 are the same as those of Example 1. It should be particularly noted here that the coolant communication ports can also be made by a laser process or other processes, and it will be obvious to those skilled in the art that guide structures must be made at appropriate positions on the outer periphery of the silicon wafer to achieve communication between the coolant communication ports and the corresponding coolant flow channels 43. In this Example, the first silicon-based electrode plate 41 and the second silicon-based electrode plate 42 can be directly fixed and stacked with a sealant (for example, the sealant layer 44 used in this Example), or in other embodiments, the fixed and stacked effect can be achieved by high-temperature sintering of a metal material.

[0051] The bipolar plate provided by this embodiment is provided with a coolant flow path 43 (water may be used as the coolant, but of course other suitable coolants may also be used), and the heat generated during the electrochemical reaction is carried away by the coolant flow path 43. Since the flow rate of the electrolyte only needs to be considered to meet the requirements of the electrochemical reaction, the flow rate of the electrolyte can be set at a low level, which can further save the energy consumed in transporting the electrolyte.

[0052] Example 5: As shown in FIG. 5, a plate of an electrolysis device, the plate being an end anode plate, the end anode plate comprising a first silicon-based plate 51 and a second silicon-based plate 52 stacked together, wherein: Each of the silicon-based electrodes 51 and 52 is provided with an electrolyte communication port, an anode product discharge port, and a coolant communication port, An anode flow path 51a communicating with the anode product outlet is provided on the outer surface of the first silicon-based electrode plate 51, The electrolyte communication port communicates with the anode flow path 51a, At the same time, a coolant flow path 53 communicating with the coolant communication port is provided between the first silicon-based electrode plate 51 and the second silicon-based electrode plate 52 .

[0053] Other implementation means of the fifth embodiment are the same as those of the fourth embodiment.

[0054] Example 6: As shown in FIG. 6, a plate of an electrolysis device, the plate being an end cathode plate, the end cathode plate comprising a first silicon-based plate 61 and a second silicon-based plate 62 stacked together, wherein: Each of the silicon-based electrodes 61 and 62 is provided with an electrolyte communication port, a cathode product discharge port, and a coolant communication port, The outer surface of the second silicon-based electrode plate 62 is provided with a cathode flow path 62a that communicates with the cathode product outlet. At the same time, a coolant flow path 63 communicating with the coolant communication port is provided between the first silicon-based electrode plate 61 and the second silicon-based electrode plate 62 .

[0055] Example 7: As shown in Figure 7, another technical solution of this Example 7 is similar to that of Example 1, with the difference being that the upper and lower surfaces of the silicon-based electrode plate 10 provided with the channel structure are subjected to a texturing process, and a textured structure 13 is further fabricated based on the channel structure (see further Figures 14 and 15).

[0056] Example 8: Another technical solution of this example 8 is the same as that of example 7, except that a porous silicon layer is further formed on the textured structure 13 by a vapor phase method.

[0057] Example 9: Another technical solution of this Example 9 is similar to that of Example 7, except that, as shown in FIG. 8, the porous pore structure 13 is further coated with a catalyst layer 14, specifically an activated nickel sulfide layer.

[0058] Example 10: Another technical solution of this Example 10 is similar to that of Example 1, with the difference being that, as shown in FIG. 9, porous silicon layers with porous pore structures are deposited on two surfaces of a silicon wafer. Preferably, in order to contribute to the flow field effect of the porous pore structure and the stability of the mechanical structure of the electrode plate, in this example, grooves 71 and 72 are pre-fabricated in the middle regions of the upper and lower surfaces of the silicon wafer, respectively (specifically, any known processing process may be used), and then porous silicon layers are fabricated in the grooves 71 and 72 by a liquid phase method or a vapor phase method (not shown).

[0059] Example 11: Another technical solution of this Example 11 is similar to that of Example 1, except that the channel structure is further coated with a catalyst layer, specifically an activated nickel sulfide layer.

[0060] Example 12: An electrolysis device electrode plate, which is an end anode plate provided by Example 2, is used, and the lower surface of the silicon-based electrode plate provided with a channel structure is subjected to a texturing process, and a textured structure is further fabricated based on the channel structure, and then a catalyst layer, specifically activated nickel sulfide, is coated on the textured structure.

[0061] Example 13: An electrolysis device electrode plate, which is an end cathode plate provided by Example 3, is used, and the upper surface of the silicon-based electrode plate provided with a channel structure is subjected to a texturing process, and a textured structure is further fabricated based on the channel structure, and then a catalyst layer, specifically an activated nickel sulfide layer, is further coated on the textured structure.

[0062] Example 14: An electrolytic device that converts electrical energy into chemical energy when connected to a DC power source and an electrolyte is injected into it. Referring to Figures 10 and 11 in combination, the electrolytic device includes an anode current collector 83a connected to the positive pole of the DC power source, a cathode current collector 83b connected to the negative pole of the DC power source, an end anode plate 84 connected in electrical contact with the anode current collector 83a, and an end cathode plate 85 connected in electrical contact with the cathode current collector 83b. To ensure a safe and reliable mounting and connection effect, an anode end plate 81 and a cathode end plate 82 are further provided at the upper and lower ends of the electrolytic device, respectively. An anode insulator 81a is provided between the anode end plate 81 and the anode current collector 83a, and a cathode insulator 82a is provided between the cathode end plate 82 and the cathode current collector 83b, thereby ensuring electrical insulation between the anode current collector 83a and the cathode current collector 83b.

[0063] Here, the end anode plate 84 of this embodiment is the end anode plate provided in Example 2, and the end cathode plate 85 of this embodiment is the end cathode plate provided in Example 3. A proton exchange membrane 86 is provided between the end anode plate 84 and the end cathode plate 85, and the outer peripheries of both plates are sealed and laminated with a sealing member 87. To further improve operating efficiency, an anode diffusion layer 87a and a cathode diffusion layer 87b are provided on both sides of the proton exchange membrane 86, respectively. An anode catalyst 88a is provided between the anode diffusion layer 87a and the proton exchange membrane 86, and a cathode catalyst 88b is provided between the cathode diffusion layer 87b and the proton exchange membrane 86. Those skilled in the art can combine and apply these components according to actual needs.

[0064] Preferably, in this Example 14, the electrolyte is pure water, and an electrochemical reaction is generated in an electrolysis device to electrolyze water to produce hydrogen and oxygen, with hydrogen being the cathode product and oxygen being the anode product.

[0065] Example 15: As shown in FIG. 12, an electrolysis device is provided in which the end anode plate provided in Example 12 is used as an end anode plate 91, the end cathode plate provided in Example 13 is used as an end cathode plate 92, a diaphragm 93 (any known diaphragm structure may be used) is provided between the end anode plate 91 and the end cathode plate 92, and the electrolyte is an aqueous NaOH solution, which are assembled using a known installation method to obtain an alkaline electrolysis device.

[0066] Example 16: Another technical solution of Example 16 is similar to that of Example 14. As shown in FIG. 13 , in the electrolysis device provided by Example 16, an electrolysis unit is provided between an end anode plate 84 and an end cathode plate 85. The electrolysis unit includes a bipolar plate 89a (specifically, the bipolar plate provided by Example 1 is used; in other embodiments, the bipolar plate provided by Example 4 may be used) and a proton exchange membrane 89b on both sides of the bipolar plate (similarly, with reference to Example 14, a diffusion layer and a catalyst may be further provided on both sides of the proton exchange membrane 89b), and is assembled to obtain a PEM electrolysis device. In other embodiments, diaphragms may be provided on both sides of the bipolar plate according to actual needs. Two or more electrolysis units connected in series and / or in parallel may be provided between the end anode plate and the end cathode plate, and when adjacent electrolysis units are connected in series and / or in parallel, the diaphragm or proton exchange membrane may be shared.

[0067] It should be further explained that in subsequent applications, the electrolyzer provided in Example 16 can be fabricated as a standard product and connected in series and / or parallel to a DC power source, and assembled to supply electrolyte to form cathode and gas, and anode and gas, to obtain electrolyzer modules with various specifications. Various electrolyzer systems can be flexibly assembled according to the size of the DC power source to be connected. More preferably, when the power supply is insufficient to operate all the electrolyzers, the operation of some of the electrolyzers can be selectively stopped, and the remaining electrolyzers can perform normal electrolysis. It should be noted that "normal electrolysis operation" herein means that these remaining electrolyzers perform electrolysis in an optimal operating state, where the optimal operating state means that the electrolyzers operate under optimal operating current density and optimal operating voltage conditions for the purpose of achieving the highest energy conversion efficiency, thereby ensuring that the entire electrolyzer module system generates hydrogen at the highest possible rate. When powered by an intermittent solar power generation system or wind power generation system, the electrolyzer system can perform electrolysis with maximum efficiency.

[0068] In order to verify the technical effects obtained in this application, the applicant performs the following measurements on Examples 15 and 16:

[0069] The voltage of the connected DC power supply was 1.75 V per electrolysis unit, the operating temperature range of the electrolysis device was 60 to 80°C, and the operating voltage range of the electrolysis device was 1.5 V to 2.4 V per electrolysis unit.

[0070] After that, the generated hydrogen flow rate was measured based on the measurement standard GB / T 19774-2005, and the measurement results are as follows.

[0071] The flow rate of hydrogen discharged in Example 15 was 0.09 Nm 3 / h, and the corresponding energy conversion efficiency is 84.6%.

[0072] The flow rate of hydrogen discharged in Example 16 was 0.2 Nm 3 / h, and the corresponding energy conversion efficiency is 84.6%.

[0073] It should be particularly noted that in the present application, the electrolysis device provided in the examples of the present application achieves an energy conversion efficiency of 84.6% under a DC power supply voltage condition of 1.75 V / each electrolysis unit, which is sufficiently surprising in the field of electrolysis and represents an outstanding inventive step.

[0074] The present invention is not limited to the details of the illustrative examples set forth above, and it will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the present invention. Accordingly, the examples are to be considered in all respects as illustrative and not limiting, and the scope of the present invention is limited not by the above description but by the appended claims, and all modifications that come within the meaning and range of equivalent elements of the claims are intended to be embraced by the present invention. Any reference numerals appearing in the claims should not be construed as limiting the scope of those claims.

[0075] Furthermore, it should be understood that although the present specification is described according to embodiments, each embodiment does not include only one separate technical solution, and such description manner in the present specification is merely for the purpose of clarifying the description, and those skilled in the art should take the present specification as a whole, and the technical solutions of each example can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. 1. A plate for an electrolysis device that converts electrical energy into chemical energy when connected to a DC power source and filled with an electrolyte, the plate comprising a silicon-based plate made of a doped conductive silicon material, the silicon-based plate being electrically connected to a DC power source and having a flow path on at least one surface thereof, such that the electrolyte is fed into the electrolysis device through the silicon-based plate, an electrochemical reaction occurs, and reaction products are discharged.

2. 2. An electrode plate for an electrolysis device according to claim 1, characterized in that the resistivity of the silicon-based electrode plate is 0.1 Ω cm or less, preferably 1-30 mΩ cm, and / or the silicon-based electrode plate is made of a monocrystalline silicon or polycrystalline silicon material, preferably monocrystalline silicon material, and / or the thickness of the silicon-based electrode plate is in the range of 0.1-10 mm, preferably 0.2-5 mm.

3. 2. The electrode plate for an electrolysis device according to claim 1, wherein the flow path comprises a channel structure consisting of staggered concave grooves and convex ridges, the width of the concave grooves being 0.2 to 5 mm, preferably 0.5 to 1 mm, the width of the convex ridges being 0.1 to 10 mm, preferably 0.2 to 0.4 mm, and the height of the convex ridges being 0.1 to 5 mm, preferably 0.12 to 0.5 mm; and / or the flow path comprises porous pores or a textured structure, the diameter of the porous pores or the feature size of the textured structure being 0.1 μm to 1000 μm, preferably 0.3 μm to 10 μm.

4. 4. The electrode plate of claim 3, wherein the channel structure is fabricated by an alkaline corrosion process or an electrochemical corrosion process, and the porous or textured structure is fabricated by a liquid phase method or a gas phase method.

5. 2. The electrode plate of claim 1, wherein at least a portion of the flow path is coated with a catalyst for promoting the electrochemical reaction, the catalyst being a metal-based catalyst or a non-metal-based catalyst, preferably an iridium-based catalyst, a platinum-based catalyst, a nickel catalyst or a nickel alloy catalyst.

6. 6. The electrode plate of claim 1 or claim 5, wherein the area ratio of the flow paths is in the range of 1.2 to 5, preferably 1.5 to 3, more preferably 1.7 to 2.

7. the plates are bipolar plates, the silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port, and a cathode product discharge port; an anode flow path communicating with the anode product outlet is provided on one surface of the silicon-based electrode plate, and a cathode flow path communicating with the cathode product outlet is provided on the other surface of the silicon-based electrode plate; The electrode plate according to any one of claims 1 to 6, wherein the electrolyte communication port communicates with the anode flow path and / or the cathode flow path.

8. The electrode plate is a bipolar electrode plate, and the bipolar electrode plate includes at least a first silicon-based electrode plate and a second silicon-based electrode plate stacked together; Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port, a cathode product discharge port, and a coolant communication port, an anode flow path communicating with the anode product outlet is provided on an outer surface of the first silicon-based electrode plate, and a cathode flow path communicating with the cathode product outlet is provided on the second silicon-based electrode plate; the electrolyte communication port communicates with the anode flow path and / or the cathode flow path; At the same time, a coolant flow path communicating with the coolant communication port is provided between the first silicon-based electrode plate and the second silicon-based electrode plate.

9. the plate being an end anode plate or an end cathode plate, the end anode plate or end cathode plate comprising a silicon-based plate made of a doped conductive silicon material; the silicon-based electrode plate is provided with an electrolyte communication port, an anode product discharge port, or a cathode product discharge port; one surface of the silicon-based electrode plate is provided with an anode flow path communicating with the anode product outlet or a cathode flow path communicating with the cathode product outlet; The electrode plate according to any one of claims 1 to 6, wherein the electrolyte communication port communicates with the anode flow path or the cathode flow path.

10. the plate is an end anode plate or an end cathode plate, the end anode plate or end cathode plate including at least a first silicon-based plate and a second silicon-based plate stacked together, each silicon-based plate being made of a doped conductive silicon material; Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product discharge port or a cathode product discharge port, and a coolant communication port, an outer surface of the first silicon-based electrode plate or the second silicon-based electrode plate is provided with an anode flow path communicating with the anode product outlet or a cathode flow path communicating with the cathode product outlet; the electrolyte communication port communicates with the anode flow path or the cathode flow path; At the same time, a coolant flow path communicating with the coolant communication port is provided between the first silicon-based electrode plate and the second silicon-based electrode plate.

11. An electrolysis device that converts electrical energy into chemical energy when connected to a DC power source and an electrolyte is injected therein, wherein the electrode plates of the electrolysis device use the electrode plates according to any one of claims 1 to 10.

12. 12. The electrolysis device according to claim 11, wherein the electrolytic solution is pure water, an alkaline aqueous solution, or an acidic aqueous solution, and generates hydrogen and oxygen by electrolyzing water through an electrochemical reaction.

13. 12. The electrolysis device according to claim 11, comprising: an anode current collector plate connected to a positive electrode of a DC power supply; a cathode current collector plate connected to a negative electrode of the DC power supply; an end anode plate connected in electrical contact with the anode current collector plate; and an end cathode plate connected in electrical contact with the cathode current collector plate, wherein a diaphragm or a proton exchange membrane, or one or more electrolysis units connected in series and / or parallel are provided between the end anode plate and the end cathode plate, and the single electrolysis unit comprises a bipolar plate and a diaphragm or a proton exchange membrane on both sides of the bipolar plate.

14. 12. The electrolysis device according to claim 11, characterized in that the electrolysis device module is produced as a standard product, connected in series and / or in parallel to a DC power source, and assembled to obtain a desired electrolysis device module, and when the power supply from the DC power source is insufficient to operate all of the electrolysis devices, the operation of some of the electrolysis devices is selectively stopped, allowing the remaining electrolysis devices to perform normal electrolysis operation.

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