Electrolytic plate and electrolytic device using the same

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 the priority of Chinese Patent Application No. 2023110128956, titled "Polar Plate of Electrolysis Device and Electrolysis Device Using the Same", filed with the Patent Office of the State Intellectual Property Office of China on August 12, 2023, and all of its contents are incorporated herein by reference.

[0002] The present invention belongs to the field of electrolysis. Specifically, it relates to the polar plate of an electrolysis device, and further relates to an electrolysis device using the polar plate.

Background Art

[0003] An electrolysis device is a device that converts electrical energy into chemical energy. Representative electrolysis devices include water electrolysis hydrogen generation devices. Hydrogen generation by water electrolysis is not only a mature technology but also an environmentally friendly and sustainable development route without carbon emission problems, so it has become the most important part of current hydrogen energy development.

[0004] Specifically, as one of the important components of an electrolysis device (such as a water electrolysis hydrogen generation device), the polar plate mainly undertakes many functions, such as mechanical support of the main structure of the electrolysis device, sealing of the body, conduction and distribution of current, transfer and distribution of reactants and products, and conduction and distribution of heat and coolant (if any).

[0005] However, electrolytic devices, especially those operating on the anode side in high-temperature and high-potential environments, have a high demand for the chemical stability of their materials. Currently, most electrolytic device electrodes use metal electrodes (metallic materials such as titanium, nickel, and stainless steel), which have poor durability under electrochemical operating conditions. To improve this durability, it is necessary to use expensive and difficult-to-process metal materials, as well as to apply expensive and complex precious metal protective films to the surface of the anode electrode. Furthermore, the electrodes of existing electrolytic devices are usually manufactured by machining, resulting in poor machining accuracy of the channel structure on the electrode, which clearly affects the mass transfer rate of reactants and products within the electrolytic device. In addition, the simple surface structure and relatively small surface area of ​​the electrode plates affect the reaction rate per unit area within the electrolytic device. Currently, no research has been reported on the use of non-metallic materials as electrode plates in the field of pure hydrogen generation by electrolysis.

[0006] Therefore, in this application, it is desirable to explore technical solutions to solve the above technical problems based on the follow-up investigation of the electrolytic device and the level of knowledge that the inventor team has accumulated regarding silicon-based materials. [Overview of the Initiative]

[0007] In view of this, the object of the present invention is to propose an electrolytic electrode plate and an electrolytic device using the same, which significantly reduce the material cost of the electrode plate of the electrolytic device while maintaining good mechanical support and sealing function, simultaneously lower the overpotential that generates the reaction products of the electrochemical reaction, increase the electrolytic reaction rate per unit area in the electrolytic device, thereby effectively reducing the operating voltage for the same electrochemical reaction rate, and ultimately significantly increasing the energy conversion efficiency of the electrochemical reaction.

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

[0009] An electrode plate for an electrolytic device that converts electrical energy into chemical energy when connected to a DC power supply and injected with an electrolyte, wherein 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 supply and has a flow path on at least one surface thereof, so that the electrolyte is sent into the electrolytic device via the silicon-based electrode plate, an electrochemical reaction occurs, and reaction products are discharged.

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

[0011] Furthermore, in this application, silicon-based electrodes made using crystalline silicon material (including single-crystal silicon or polycrystalline silicon) have a higher thermal conductivity than metals. Therefore, the silicon-based electrodes provided in this application can better conduct and distribute the heat generated in the electrochemical reaction of an electrolytic device. In addition, electrolytic devices using the silicon-based electrodes provided in this application will have higher temperature uniformity, reducing the impact of temperature non-uniformity on the performance and lifespan of the electrolytic device. Moreover, silicon-based electrodes can not only create fine channel structures, but also precisely control the consistency between the flow field structure and surface shape of the silicon-based electrodes. In subsequent applications, if a multilayer electrolytic device is obtained by stacking multiple electrolytic units made from silicon-based electrodes, the performance of each electrolytic unit in the multilayer electrolytic device will be more stable. This will contribute to the application need to increase the number of electrolytic units in the multilayer electrolytic device, further improving the performance and lifespan of the multilayer electrolytic device.

[0012] Preferably, the channel includes a channel structure composed of staggered concave grooves and convex ridges, where 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; the height of the convex ridges is 0.1 to 5 mm, preferably 0.12 to 0.5 mm; and / or, the channel includes a porous pore or textured structure, where 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, the liquid-phase method specifically includes processes such as selective corrosion, electrochemical corrosion, and catalytic corrosion, and the gas-phase method includes processes such as plasma etching. All of these processes are well known and can be used to fabricate various desired channel structures, porous pore structures, or textured structures according to actual application needs, thereby increasing the effective contact area between the catalyst and electrolyte on the silicon-based electrode plate while achieving the delivery of electrolyte to the electrolytic device, thereby increasing the mass transfer rate of reaction raw materials and reaction products and / or the reaction rate on the silicon-based electrode plate surface in the electrochemical reaction.

[0014] Preferably, at least a portion of the flow path is coated with a catalyst to promote the electrochemical reaction, and the catalyst is either 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 channel 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 of the total surface area of ​​the channel 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) to the area occupied by the surface of the channel within the electrolytic cell. Here, the "total surface area of ​​the channel exposed to the electrolyte" and the "area occupied by the surface of the channel within the electrolytic cell" according to this application can be obtained by performing an electron microscope scan on the electrode plate using a well-known scanning electron microscope (SEM). The electron microscope scan measures the surface area of ​​the channel exposed to the electrolyte and the area occupied by the surface of the channel within the electrolytic cell, respectively, and further the area ratio of the channel can be obtained.

[0016] Preferably, the electrode plate is a bipolar electrode plate, where, 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, One side of the silicon-based electrode plate is provided with an anode channel that communicates with the anode product outlet, and the other side is provided with a cathode channel that communicates with the cathode product outlet. The electrolyte communication port communicates with the anode channel and / or the cathode channel.

[0017] Preferably, 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 laminated together as a single unit, where, Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product outlet, a cathode product outlet, and a coolant communication port. The outer surface of the first silicon-based electrode plate is provided with an anode channel that communicates with the anode product outlet, and the second silicon-based electrode plate is provided with a cathode channel that communicates 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 electrode plate is an end anode plate or an end cathode plate, and the end anode plate or end cathode plate includes a silicon-based electrode plate made of a doped conductive silicon material, where, 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 channel communicating with the anode product outlet, or a cathode channel communicating with the cathode product outlet. The electrolyte communication port communicates with the anode channel or the cathode channel.

[0019] Preferably, the electrode plate is an end anode plate or an end cathode plate, and the end anode plate or end cathode plate includes at least a first silicon base plate and a second silicon base plate laminated together, and each silicon base plate is made of a doped conductive silicon material, where, Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product outlet or a cathode product outlet, and a coolant communication port. The outer surface of the first silicon-based electrode plate or the second silicon-based electrode plate is provided with an anode channel communicating with the anode product outlet, or a cathode channel communicating with the cathode product outlet. The electrolyte communication port communicates with the anode channel or the cathode channel, 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 electrolytic device is connected to a DC power supply and, when an electrolyte is injected, converts electrical energy into chemical energy, and the electrode plates of the electrolytic device are as described above.

[0021] Preferably, the electrolytic solution is pure water, an alkaline aqueous solution, or an acidic aqueous solution, and water is electrolyzed by an electrochemical reaction to generate hydrogen and oxygen.

[0022] Preferably, the electrolysis device includes an anode current collector plate connected to the positive electrode of a DC power source, a cathode current collector plate connected to the negative electrode of the DC power source, an end anode plate electrically and contactingly connected to the anode current collector plate, and an end cathode plate electrically and contactingly connected to the cathode current collector plate. Between the end anode plate and the end cathode plate, a diaphragm, a proton exchange membrane, or one or more electrolysis units connected in series and / or in parallel are provided. The single electrolysis unit includes a bipolar plate and diaphragms or proton exchange membranes on both sides of the bipolar plate.

[0023] Preferably, the electrolysis device is manufactured 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. Here, if the power supply from the DC power source is insufficient to operate all the electrolysis devices, the operation of some of the electrolysis devices is selectively stopped so that the remaining electrolysis devices can perform electrolysis operation normally.

[0024] Regarding the operating principle and advantages of the present invention, before presenting the idea of the present invention, the applicant found that in the prior art, in order to achieve functions such as good mechanical support, excellent current conduction, heat conduction and heat distribution, and distribution of reactants and products, it is usually considered to use a metal material electrode plate as the electrode plate of the water electrolysis device (in particular, the use of a carbon steel plate or titanium plate with a thickness of 2 to 5 mm is always preferentially considered). The applicant also found that when using a silicon wafer to fabricate the electrode of a silicon-based electrolysis device, not only good mechanical support and sealing function are maintained, but also due to the abundance of silicon material resources and the maturity of the silicon wafer processing technology, the material and process costs of the electrode plate of the electrolysis device are significantly reduced. In particular, it should be noted that in this application, it is proposed to electrically connect a silicon-based electrode plate to a DC power supply and fabricate a desired precise flow path on the silicon-based electrode plate to form a precise and reliable flow field distribution, so as to improve the mass transfer rate of reactants and products in the electrolysis device, reduce the overpotential of the electrolysis reaction, and by fabricating a rich surface shape on the silicon-based electrode plate with a flow field, the contact area between the electrolyte and the electrode plate can be effectively increased, so the overpotential of the electrochemical reaction is reduced. In this application, the overpotential of the electrochemical reaction can be reduced from multiple aspects, so the operating voltage of the electrochemical reaction is effectively reduced, and finally the energy conversion efficiency of the electrochemical reaction is significantly increased. Furthermore, compared with the metal-based electrodes of the prior art, this application clearly improves the uniformity of the operating temperature of the electrochemical reaction and the consistency of each unit in the electrolysis device composed of multiple electrochemical reaction units, and can further improve the electrolysis performance and lifespan of the electrolysis device.

Brief Description of the Drawings

[0025] [Figure 1] It is a schematic diagram showing the structure of the bipolar electrode plate of Example 1 based on the specific embodiment of the present invention. [Figure 2] It is a schematic diagram showing the structure of the end anode plate of Example 2 based on the specific embodiment of the present invention. [Figure 3]This is a schematic diagram showing the structure of the end cathode plate of Example 3, which is based on a specific embodiment of the present invention. [Figure 4] This is a schematic diagram showing the structure of a bipolar electrode plate in Example 4, based on a specific embodiment of the present invention. [Figure 5] This is a schematic diagram showing the structure of the end anode plate of Example 5, which is based on a specific embodiment of the present invention. [Figure 6] This is a schematic diagram showing the structure of the end cathode plate of Example 6, which is based on a specific embodiment of the present invention. [Figure 7] This is a schematic diagram showing the structure of a bipolar electrode plate in Example 7, based on a specific embodiment of the present invention. [Figure 8] This is a schematic diagram showing the structure of a bipolar electrode plate in Example 9, based on a specific embodiment of the present invention. [Figure 9] This is a schematic diagram showing the structure of a bipolar electrode plate in Example 10, based on a specific embodiment of the present invention. [Figure 10] This is a schematic diagram showing the electrode plate mounting structure of an electrolytic apparatus according to Example 14, which is based on a specific embodiment of the present invention. [Figure 11] This is a schematic diagram showing the mounting structure of an electrolytic device according to Example 14, which is based on a specific embodiment of the present invention. [Figure 12] This is a schematic diagram showing the electrode plate mounting structure of an electrolytic apparatus according to Example 15, which is based on a specific embodiment of the present invention. [Figure 13] This is a schematic diagram showing the mounting structure of an electrolytic device according to Example 16, which is based on a specific embodiment of the present invention. [Figure 14] This is an SEM image of the texture structure 13 on a silicon-based electrode plate in Example 7, which is based on a specific embodiment of the present invention. [Figure 15] This is another SEM image of the texture structure 13 on the silicon-based electrode plate of Example 7, based on a specific embodiment of the present invention. [Modes for carrying out the invention]

[0026] Embodiments of the present invention disclose an electrode plate of an electrolytic device, which converts electrical energy into chemical energy when connected to a DC power supply and injected with an electrolyte, and the electrode plate includes a silicon-based electrode plate made of a doped conductive silicon material, wherein the silicon-based electrode plate is electrically connected to a DC power supply and has a channel (the channel is for transporting and distributing the electrolyte or reaction products) on at least one surface thereof, so that the electrolyte is sent into the electrolytic device through the channel on the silicon-based electrode plate, an electrochemical reaction occurs, and the reaction products are discharged.

[0027] Preferably, in this embodiment, the resistivity of the silicon-based electrode 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 / or, preferably, in this embodiment, the silicon-based electrode is made of crystalline silicon (which may include crystalline types such as single-crystal silicon or polycrystalline silicon, and may also include doped types such as N-type doped crystalline silicon or P-type doped crystalline silicon), preferably made of single-crystal silicon, and more preferably the crystal orientation is <111> It is a crystal direction other than the crystal direction, specifically, <100> Crystal orientation, or <110> Crystal orientation, or <111> A crystal direction that is clearly at an angle to the crystal direction, most preferably <100> This is the crystal orientation.

[0028] And / or, preferably in this embodiment, the thickness of the silicon base 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 base plate may be square, circular, or any other desired shape, and this application is not limited to any particular embodiment. The substrate of the silicon base plate used in this application may be a silicon wafer obtained by cutting, which may be further polished chemically or mechanically to improve the surface flatness, thereby contributing to the processing effect of the silicon wafer by subsequent processes, and when implementing this application, the thickness and shape of the silicon base plate may be selected according to the dynamic development level of the silicon wafer cutting and processing process, and this application is not particularly limited to a single range. Preferably, in this embodiment, the channel includes a channel structure composed of staggered concave grooves and convex ridges, where 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; 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 / or, preferably, in this embodiment, the channel includes porous pores or textures The structure includes a channel structure, and in actual implementation, the porous pore or texture structure may be formed on a silicon base electrode plate alone, or in a silicon base electrode plate provided with a channel structure, it may be further formed on the surface of the silicon base electrode plate where the channel structure is located. Preferably, in this embodiment, the diameter of the porous pores or the feature size of the texture structure is 0.1 μm to 1000 μm, preferably 0.3 μm to 10 μm. In this way, in actual application, the electrolytic device can obtain an electrode plate having 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, and in practice, the alkaline corrosion process can be any well-known alkaline corrosion process or any well-known electrochemical corrosion process, and more preferably, in this embodiment, for silicon-based electrodes made of N-type doped crystalline silicon, corrosion with a strong alkaline solution or electrochemical corrosion is recommended, and for silicon-based electrodes made of P-type doped crystalline silicon, corrosion by an electrochemical process is recommended, and preferably, in this embodiment, the strong alkaline solution is organic or inorganic strong alkaline water. A solution can be selected, and the mass concentration of the strong alkaline solution is recommended to be in the range of 10% to 50%, preferably an aqueous KOH solution with a mass concentration of 25% to 35%, and the corrosion temperature is 50 to 120°C, preferably 70 to 85°C for the alkaline corrosion process. Of course, in other embodiments, other methods may be used to process and fabricate the desired channel structure of this embodiment, preferably, in this embodiment, the porous pore structure or texture structure is fabricated by a liquid-phase method or a gas-phase method, where the liquid-phase method includes processes such as selective corrosion, electrochemical corrosion, and catalytic corrosion, and the gas-phase method includes processes such as plasma etching. Specifically, surface texturing of the silicon-based electrode plate may be performed using any well-known silicon wafer texturing process (belonging to selective corrosion in the liquid-phase method), and a porous silicon layer (i.e., porous pore structure) may be fabricated using any well-known process (e.g., gas-phase deposition).Texturing increases the area ratio of the silicon-based electrode plate, increasing the electrochemical reaction rate per unit area of ​​the electrode plate surface in the electrolytic device. This not only improves the performance of the electrolytic device but also reduces its cost. 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. This not only significantly increases the area ratio of the electrode plate but also improves the transfer and flow efficiency of the electrolyte and reaction products (mainly in gaseous form) in the electrode plate's flow path, increasing the electrochemical reaction rate per unit area of ​​the electrolytic device. Furthermore, the porous pore structure reduces the hydrophobicity and aerobicity of the electrode plate, suppressing the generation of large bubbles in the flow path (including the exchange of reaction raw materials and reaction products in the flow path, if any). This, in turn, further improves the electrochemical reaction rate and energy conversion efficiency of the electrolytic device using it.

[0030] Preferably, in this embodiment, a catalyst for promoting an electrochemical reaction is coated in at least a portion of the flow channels (specifically, at least a portion of the channel structure, or at least a portion of the porous pore structure, or at least a portion of the texture structure), and the catalyst is either a metal-based catalyst or a non-metal-based catalyst, where preferably, in this embodiment, the metal-based catalyst includes noble metal-based catalysts and non-noble metal-based catalysts, where the noble metal-based catalyst is selected from, for example, one or more of Ir, Pt, Pd, Au, and Ag, the non-noble metal-based catalyst is selected from, for example, one or more of Fe, Co, Ni, and Al, and the non-metal-based catalyst is selected from, for example, carbon materials or carbon composite materials. As selected and confirmed in the experiments of this application, suitable catalysts for applications of alkaline electrolytic devices that match silicon-based electrodes include, for example, noble metal catalysts such as alloys of Ir and Al, and non-noble metal nickel-based catalysts (i.e., catalysts containing nickel Ni components, nickel catalysts, or nickel alloy catalysts). Nickel catalysts may specifically include pure electroplated nickel, and nickel alloy catalysts may include, for example, Raney nickel, activated nickel sulfide, Ni-Mo alloys, or highly active nickel alloy catalysts such as activated NiAl. In practical implementation, an appropriate catalyst will be selected according to specific requirements of cost and / or performance, and is not limited to those in this embodiment. As confirmed in experiments, when a catalyst layer is provided on the electrode provided by the embodiments of this application, in specific applications, it is not necessary to provide a diffusion layer on the diaphragm or proton exchange membrane, further saving structural costs.

[0031] In implementing this application, the catalyst can be coated using any known method, although not particularly limited, such as spray coating, printing, electroplating, or PVD. Specifically, when the catalyst is directly coated into a channel structure, electroplating, PVD, or other integral film deposition coating methods are recommended, and when the catalyst is coated into a porous structure, physical coating methods such as spray coating or printing 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 actual applications, it is possible not only to significantly reduce the overpotential required to generate an electrochemical reaction in the electrolytic device, but also to increase the reaction rate per unit area. It should be particularly noted that if a catalyst is coated in 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, depending on the specific needs of the electrolytic device, this application allows for the fabrication of different bipolar plates, end anodes, or end cathodes based on the plate solutions provided by the embodiments described above, and is not limited to these embodiments.

[0034] Preferably, this embodiment proposes an electrolytic device that converts electrical energy into chemical energy when connected to a DC power supply and injected with electrolyte, wherein the electrodes of the electrolytic device use the electrodes described above.

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

[0036] Preferably, in this embodiment, the electrolytic device includes an anode end plate connected to the positive electrode of a DC power supply, a cathode end plate connected to the negative electrode of a DC power supply, an end anode plate electrically connected to the anode end plate, and an end cathode plate electrically connected to the cathode end plate. Between the end anode plate and the end cathode plate, there is a diaphragm or a proton exchange membrane, or one or more electrolytic units connected in series and / or parallel, and a single electrolytic unit includes a bipolar electrode plate and a diaphragm or proton exchange membrane on both sides of the bipolar electrode plate.

[0037] Furthermore, it should be noted that the electrode plate structure provided in this embodiment can be applied to various types of electrolytic devices depending on the actual needs, including, but not limited to, alkaline electrolytic devices (also called alkaline electrolytic cells) and PEM (proton exchange membrane) electrolytic devices (also called PEM electrolytic cells), and of course, they can be applied to other types of electrolytic devices with similar needs, all of which are general choices made by those skilled in the art based on the scope described in this application, and further explanation is omitted for the embodiments of this application.

[0038] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below. Naturally, the drawings in the following description are only a few embodiments of the present invention, and those skilled in the art can obtain other drawings based on these without requiring any creative effort.

[0039] Example 1: As shown in Figure 1, the electrode plate of a water electrolysis apparatus is a bipolar electrode plate, and includes a silicon-based electrode plate 10 made of doped conductive silicon material, where, The silicon-based electrode plate 10 is provided with an electrolyte communication port, an anode product discharge port, and a cathode product discharge port, respectively. An anode channel 11 communicating with an anode product outlet is provided on the lower surface of the silicon base electrode plate 10, and a cathode channel 12 communicating with a cathode product outlet is provided on its upper surface. The electrolyte communication port communicates with the anode channel 11, and in other embodiments, as a second preferred embodiment, it may communicate with the cathode channel 12, or it may communicate with both the anode channel 11 and the cathode channel 12.

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

[0041] Using a 30% mass concentration KOH aqueous solution, two surfaces of a silicon wafer are selectively etched to obtain a silicon-based electrode plate having channel structures on its upper and lower surfaces, respectively. Here, the channel structure on the upper surface of the silicon-based electrode plate 10 is designated as the cathode channel 12, and the channel structure on the lower surface of the silicon-based electrode plate 10 is designated as the anode channel 11.

[0042] In specific implementation, the channel structure of the cathode channel 12 and the channel structure of the anode channel 11 may be the same or different in size. Furthermore, the channel structure in the same electrode channel (e.g., anode channel 11, cathode channel 12) can be configured so that wide channel units and narrow channel units are arranged alternately. This allows for better fluid transport efficiency, further improves the efficiency of the electrochemical reaction, and reduces the power consumption required to drive the flow of reactants and products within the electrolytic device.

[0043] In this embodiment, the channel structure that becomes the anode channel 11 has a concave groove 11a with a width of 0.8 mm, a depth of 0.2 mm, and a convex ridge 11b with a width of 0.4 mm. The channel structure that becomes the cathode channel 12 is the same as the channel structure that becomes the anode channel 11, with a concave groove 12a with a width of 0.8 mm, a depth of 0.15 mm, and a convex ridge 12b with a width of 0.4 mm. The electrolyte communication port, anode product outlet, and cathode product outlet are fabricated on the silicon wafer by a laser process or other process, and these two steps can be carried out in any order according to the actual needs.

[0044] It is obvious to those skilled in the art that, in order to achieve the effect of communication between the electrolyte communication port, anode product discharge port, and cathode product discharge port and the corresponding flow channels, a guide structure must be fabricated at an appropriate position on the outer periphery of the silicon wafer, and the electrolyte, anode product, and cathode product must be introduced from the electrode plate flow field to the electrolytic device and discharged from the electrolytic device, respectively. Specifically, it is preferable to fabricate a channel structure and a guide structure, which will not be explained in detail in this embodiment.

[0045] In this embodiment, a single silicon wafer is used as the substrate for the silicon-based electrode plate 10, and when applied to a PEM water electrolysis apparatus, there is 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 electrolytic hydrogen generation. In this embodiment, since the cooling effect is achieved by the electrolyte supplied directly to the anode channel, it is recommended to set a high flow rate for the electrolyte, which in turn requires the consumption of more electrolyte driving power.

[0046] Example 2: As shown in Figure 2, the electrode plate of an electrolytic device is an end anode plate, and the end anode plate includes a silicon-based electrode plate 20 made of doped conductive silicon material, where, The silicon-based electrode plate 20 is provided with an electrolyte communication port and an anode product discharge port. An anode channel 21 communicating with an anode product outlet is provided on the lower surface of the silicon base electrode plate 20. The electrolyte communication port is connected to the anode flow path 21.

[0047] Other means of implementation in this embodiment 2 are the same as in embodiment 1.

[0048] Example 3: As shown in Figure 3, the electrode plate of an electrolytic device is preferably an end cathode plate, and the end cathode plate includes a silicon-based electrode plate 30 made of a doped conductive silicon material, where, The silicon-based electrode plate 30 is provided with an electrolyte communication port and a cathode product discharge port. A cathode channel 31 communicating with a cathode product discharge port is provided on the upper surface of the silicon base electrode plate 30. Other means of implementation in this embodiment 3 are the same as in embodiment 1.

[0049] Example 4: As shown in Figure 4, the electrode plate of an electrolytic device is a bipolar electrode plate, and the bipolar electrode plate includes a first silicon-based electrode plate 41 and a second silicon-based electrode plate 42 which are laminated together as a single unit, where, Each silicon-based electrode plate 41, 42 is provided with an electrolyte communication port, an anode product discharge port, a cathode product discharge port, and a coolant communication port, respectively. An anode channel 41a communicating with an anode product outlet is provided on the outer surface of the first silicon base electrode plate 41, and a cathode channel 42a communicating with a cathode product outlet is provided on the second silicon base electrode plate 42. The electrolyte communication port is in communication with the anode flow path 41a. At the same time, a coolant flow path 43 is provided between the first silicon base electrode plate 41 and the second silicon base electrode plate 42, which communicates with a coolant communication port.

[0050] Other means of implementation in this embodiment 4 are the same as in embodiment 1. It is particularly noteworthy that the coolant communication port can similarly be fabricated by a laser process or other process, and it is obvious to those skilled in the art that a guide structure must be fabricated at an appropriate position on the outer periphery of the silicon wafer in order to achieve the effect of communication between the coolant communication port and the corresponding coolant flow path 43. In this embodiment, the first silicon base plate 41 and the second silicon base plate 42 can be fixed and laminated directly with a sealing material (e.g., the sealing layer 44 used in this embodiment), and in other embodiments, the fixed lamination effect can also be achieved by high-temperature sintering with a metallic material.

[0051] The bipolar electrode plate provided in this embodiment is equipped with a coolant channel 43 (water may be used as the coolant, but of course, other suitable substances may also be used), and the heat generated during the electrochemical reaction is carried away by the coolant channel 43, and the flow rate of the electrolyte only needs to be considered to satisfy the requirements of the electrochemical reaction, so the flow rate of the electrolyte may be set to a low level, thereby further saving the energy consumed in transferring the electrolyte.

[0052] Example 5: As shown in Figure 5, the electrode plate of an electrolytic device is an end anode plate, and the end anode plate includes a first silicon-based electrode plate 51 and a second silicon-based electrode plate 52 which are laminated together as a single unit, Each silicon-based electrode plate 51, 52 is provided with an electrolyte communication port, an anode product discharge port, and a coolant communication port, respectively. An anode channel 51a communicating with an anode product outlet is provided on the outer surface of the first silicon base electrode plate 51. The electrolyte communication port is in communication with the anode flow path 51a. At the same time, a coolant flow path 53 is provided between the first silicon base electrode plate 51 and the second silicon base electrode plate 52, which communicates with a coolant communication port.

[0053] Other means of implementation in this embodiment 5 are the same as in embodiment 4.

[0054] Example 6: As shown in Figure 6, the electrode plate of an electrolytic device is an end cathode plate, and the end cathode plate includes a first silicon-based electrode plate 61 and a second silicon-based electrode plate 62 which are laminated together as a single unit, where, Each silicon base electrode plate 61, 62 is provided with an electrolyte communication port, a cathode product discharge port, and a coolant communication port, respectively. A cathode channel 62a communicating with a cathode product outlet is provided on the outer surface of the second silicon base electrode plate 62. At the same time, a coolant flow path 63 is provided between the first silicon-based electrode plate 61 and the second silicon-based electrode plate 62, which communicates with a coolant communication port.

[0055] Example 7: As shown in Figure 7, another technical solution in this Example 7 is the same as in Example 1, the difference being that the upper and lower surfaces of the silicon-based electrode plate 10, which has a 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 in Example 8 is similar to that in Example 7, the difference being that a porous silicon layer is further formed on the texture structure 13 by a vapor phase method.

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

[0058] Example 10: Another technical solution in Example 10 is the same as in Example 1, with the difference being that, as shown in Figure 9, a porous silicon layer with a porous pore structure is deposited on two surfaces of the 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, concave grooves 71 and 72 are pre-fabricated in the intermediate region between the upper and lower surfaces of the silicon wafer (specifically, any well-known processing process may be used), and then a porous silicon layer is fabricated in the concave grooves 71 and 72 by a liquid-phase method or a gas-phase method (not shown).

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

[0060] Example 12: An electrode plate for an electrolytic device, using the end anode plate provided in Example 2, the lower surface of the silicon-based electrode plate with a channel structure is subjected to a texturing process, and a textured structure is further created based on the channel structure. Subsequently, a catalyst layer, specifically activated nickel sulfide, is coated onto the textured structure.

[0061] Example 13: An electrode plate for an electrolytic device, using the end cathode plate provided in Example 3, wherein the upper surface of the silicon-based electrode plate having a channel structure is subjected to a texturing process, and a textured structure is further created based on the channel structure, and thereafter the textured structure is further coated with a catalyst layer, specifically an activated nickel sulfide layer.

[0062] Example 14: An electrolytic device that converts electrical energy into chemical energy when connected to a DC power supply and injected with electrolyte. Referring to Figures 10 and 11 in combination, the electrolytic device includes an anode current collector plate 83a connected to the positive electrode of the DC power supply, a cathode current collector plate 83b connected to the negative electrode of the DC power supply, an end anode plate 84 electrically connected to the anode current collector plate 83a, and an end cathode plate 85 electrically connected to the cathode current collector plate 83b. In order to obtain 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. Here, an anode insulating member 81a is provided between the anode end plate 81 and the anode current collector plate 83a, and a cathode insulating member 82a is provided between the cathode end plate 82 and the cathode current collector plate 83b, thereby ensuring electrical insulation between the anode current collector plate 83a and the cathode current collector plate 83b.

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

[0064] Preferably, in this embodiment 14, the electrolyte is pure water, and by generating an electrochemical reaction in an electrolytic device, water is electrolyzed to produce hydrogen and oxygen, where hydrogen becomes the cathode product and oxygen becomes the anode product.

[0065] Example 15: As shown in Figure 12, an electrolytic apparatus is provided in which the end anode plate provided in Example 12 is used as the end anode plate 91, the end cathode plate provided in Example 13 is used as the 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, the electrolyte is an aqueous NaOH solution, and an alkaline electrolytic apparatus is obtained by combining them using a known mounting method.

[0066] Example 16: Another technical solution in Example 16 is similar to that in Example 14, as shown in Figure 13, in the electrolytic apparatus provided by Example 16, one electrolytic unit is provided between an end anode plate 84 and an end cathode plate 85, the electrolytic unit comprising a bipolar electrode plate 89a (specifically, the bipolar electrode plate provided in Example 1 is used, and in other embodiments, the bipolar electrode plate provided in Example 4 may be used) and proton exchange membranes 89b on both sides of the bipolar electrode plate (similarly, referring to Example 14, diffusion layers and catalysts may be further provided on both sides of the proton exchange membrane 89b), and these are assembled to obtain a PEM electrolytic apparatus, in other embodiments, depending on the actual needs, diaphragms may be provided on both sides of the bipolar electrode plate, and two or more electrolytic units may be provided between the end anode plate and the end cathode plate, connected in series and / or in parallel, where if adjacent electrolytic units are connected in series and / or in parallel, diaphragms or proton exchange membranes may be shared.

[0067] Furthermore, in subsequent applications, the electrolytic apparatus provided by this embodiment 16 may be manufactured as a standard product, connected in series and / or parallel to a DC power supply, assembled to supply electrolyte to generate a cathode and gas, and to generate an anode and gas, thereby obtaining electrolytic apparatus modules of various specifications. Depending on the magnitude of the DC power supply to which it is connected, various electrolytic apparatus systems can be flexibly assembled. More preferably, if the power supply is insufficient to operate all the electrolytic apparatuses, the operation of some electrolytic apparatuses may be selectively stopped, allowing the remaining electrolytic apparatuses to operate normally. It should be noted that "operating normally" here means that these remaining electrolytic apparatuses operate under optimal operating conditions, where optimal operating conditions mean that the electrolytic apparatuses 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 electrolytic apparatus module system generates hydrogen at the highest possible rate. The electrolytic apparatus system can operate with maximum efficiency when powered by intermittently generating solar or wind power systems.

[0068] To verify the technical effects obtained in this application, the applicant measures the following for Examples 15 and 16.

[0069] The connected DC power supply voltage is 1.75V / each electrolytic unit, the operating temperature range of the electrolytic device is 60~80°C, and the operating voltage range of the electrolytic device is 1.5V~2.4V / each electrolytic unit.

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

[0071] The hydrogen flow rate discharged in Example 15 is 0.09 Nm³. 3 The value is / h, and the corresponding energy conversion efficiency is 84.6%.

[0072] The hydrogen discharged in Example 16 is 0.2 Nm³. 3 The value is / h, and the corresponding energy conversion efficiency is 84.6%.

[0073] In particular, it should be noted that, under the voltage condition of 1.75V / DC power supply for each electrolytic unit, the electrolytic apparatus provided by the embodiment of this application achieves an energy conversion efficiency of 84.6%, which is quite remarkable in the field of electrolysis and represents outstanding inventiveness.

[0074] The present invention is not limited to the details of the exemplary embodiments described above, and it will be obvious to those skilled in the art that the invention can be carried out in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in any respect, and the scope of the invention is limited not by the above description but by the appended claims; thus, all variations falling within the meaning and scope of equivalent elements of the claims are intended to be included in the invention. Any reference number assigned to the claims should not be considered to limit the scope of those claims.

[0075] Furthermore, as can be understood, although this specification is described according to embodiments, each embodiment does not consist of only one distinct technical solution, and such description in this specification is merely for the purpose of clarifying the explanation, and those skilled in the art should view this specification as a whole, and the technical solutions of each embodiment can also be appropriately combined to form other embodiments that will be understood by those skilled in the art.

Claims

1. An electrode plate of an electrolytic device, wherein when the electrolytic device is connected to a DC power supply and an electrolyte is injected, it converts electrical energy into chemical energy, 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 supply and has a flow path on at least one surface thereof, so that the electrolyte is sent into the electrolytic device via the silicon-based electrode plate, an electrochemical reaction occurs, and reaction products are discharged, The resistivity of the silicon-based electrode plate is 0.1 Ω·cm or less, the silicon-based electrode plate is made of single-crystal silicon or polycrystalline silicon material, and the thickness of the silicon-based electrode plate is in the range of 0.1 to 10 mm. The channel includes a channel structure composed of staggered concave grooves and convex ridges, the width of the concave grooves being 0.2 to 5 mm, the width of the convex ridges being 0.1 to 10 mm, the height of the convex ridges being 0.1 to 5 mm, and / or the channel includes a porous pore structure or a textured structure, the diameter of the porous pore structure or the feature size of the textured structure being 0.1 μm to 1000 μm. An electrolytic device electrode plate characterized by the following features.

2. The electrode plate of the electrolytic apparatus according to claim 1, characterized in that the resistivity of the silicon-based electrode plate is 1 to 30 mΩ·cm, and / or the silicon-based electrode plate is made of a single-crystal silicon material, and / or the thickness range of the silicon-based electrode plate is 0.2 to 5 mm.

3. The electrode plate of the electrolytic apparatus according to Claim 1, characterized in that the width of the concave groove is 0.5 to 1 mm, the width of the convex ridge is 0.2 to 0.4 mm, the height of the convex ridge is 0.12 to 0.5 mm, and / or the diameter of the porous pore structure or the feature size of the texture structure is 0.3 μm to 10 μm.

4. The electrode plate of the electrolytic apparatus according to claim 1, characterized in that the channel structure is produced by an alkaline corrosion process or an electrochemical corrosion process, and the porous pore structure or texture structure is produced by a liquid-phase method or a gas-phase method.

5. The electrode plate of the electrolytic apparatus according to claim 1, characterized in that at least a portion of the flow path is coated with a catalyst for promoting an electrochemical reaction, and the catalyst is a metal-based catalyst or a non-metal-based catalyst.

6. The area ratio of the aforementioned flow path is in the range of 1.2 to 5. The electrode plate of the electrolytic apparatus according to claim 1, characterized in that the area ratio is the ratio of the total surface area of ​​the flow channels exposed to the electrolyte to the area occupied by the surface of the flow channels within the electrolytic cell.

7. The aforementioned electrode plate is a bipolar electrode plate. 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, One side of the silicon-based electrode plate is provided with an anode channel that communicates with the anode product outlet, and the other side is provided with a cathode channel that communicates with the cathode product outlet. The electrode plate according to any one of claims 1 to 6, characterized in that 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 that are laminated together as a single unit. Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product outlet, a cathode product outlet, and a coolant communication port. The outer surface of the first silicon-based electrode plate is provided with an anode channel that communicates with the anode product outlet, and the second silicon-based electrode plate is provided with a cathode channel that communicates with the cathode product outlet. The electrolyte communication port communicates with the anode flow path and / or the cathode flow path, The electrode plate according to any one of claims 1 to 6, characterized in that 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 electrode plate is an end anode plate or an end cathode plate, and the end anode plate or end cathode plate includes a silicon-based electrode 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 channel communicating with the anode product outlet, or a cathode channel communicating with the cathode product outlet. The electrode plate according to any one of claims 1 to 6, characterized in that the electrolyte communication port communicates with the anode flow path or the cathode flow path.

10. The electrode plate is an end anode plate or an end cathode plate, and the end anode plate or end cathode plate includes at least a first silicon base plate and a second silicon base plate laminated together, and each silicon base plate is made of a doped conductive silicon material. Each silicon-based electrode plate is provided with at least an electrolyte communication port, an anode product outlet or a cathode product outlet, and a coolant communication port. The outer surface of the first silicon-based electrode plate or the second silicon-based electrode plate is provided with an anode channel communicating with the anode product outlet, or a cathode channel communicating with the cathode product outlet. The electrolyte communication port communicates with the anode channel or the cathode channel, The electrode plate according to any one of claims 1 to 6, characterized in that 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 electrolytic device that converts electrical energy into chemical energy when connected to a DC power supply and injected with an electrolyte, characterized in that the electrode plates of the electrolytic device use the electrode plates described in any one of claims 1 to 6.

12. The electrolytic apparatus according to claim 11, characterized in that 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.

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

14. The electrolytic device according to claim 11, characterized in that the electrolytic device is manufactured as a standard product, connected in series and / or parallel to a DC power supply and assembled to obtain a desired electrolytic device module, and if the power supply from the DC power supply is insufficient to operate all the electrolytic devices, the operation of some of the electrolytic devices is selectively stopped so that the remaining electrolytic devices can perform electrolytic operation normally.

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