Electrolytic device and its application

Abstract

The application discloses an electrolytic device polar plate and an electrolytic device using the same. The electrolytic device is connected to a direct current power supply and injects electrolyte, and converts electric energy into chemical energy. The polar plate comprises a silicon-based polar plate made of doped conductive silicon material. The silicon-based polar plate is connected to the direct current power supply, and at least one surface of the silicon-based polar plate is provided with a flow channel, so that the electrolyte is input into the electrolytic device through the silicon-based polar plate, electrochemical reaction occurs, and reaction products are output. The application significantly reduces the material and process cost of the polar plate of the electrolytic device, while reducing the overpotential of the electrochemical reaction to generate reaction products, increasing the electrolytic reaction speed per unit area of the electrolytic device, thereby effectively reducing the working voltage of the same electrochemical reaction speed, and finally significantly increasing the energy conversion efficiency of the electrochemical reaction.

Description

Technical Field

[0001] This invention belongs to the field of electrolysis, and specifically relates to an electrode plate of an electrolysis device. This invention also relates to an electrolysis device using the electrode plate. Background Technology

[0002] Electrolysis equipment is a device that converts electrical energy into chemical energy. Typical electrolysis equipment includes water electrolysis for hydrogen production. Hydrogen production via water electrolysis is not only a mature technology but also eliminates carbon emissions, making it a green and sustainable development approach. Currently, water electrolysis for hydrogen production has become one of the most important links in the development of hydrogen energy.

[0003] Specifically, the electrode plate is one of the key components of an electrolysis device (such as an electrolysis water hydrogen production device). It mainly serves multiple functions, including mechanical support of the main structure of the electrolysis device, sealing, current conduction and distribution, transmission and distribution of reactants and products, and transmission and distribution of heat and coolant (if any).

[0004] However, because electrolysis devices, especially the anode side, operate in a high-temperature, high-potential environment, the chemical stability of materials is critical. Currently, most electrolysis device electrodes are made of metal (titanium, nickel, stainless steel, etc.), which exhibit poor durability in electrochemical environments. To improve durability, expensive and difficult-to-process metal materials are needed, along with costly and complex precious metal protective coatings on the anode surface. Furthermore, existing electrolysis device electrodes are typically manufactured using machining, resulting in poor dimensional accuracy of the flow channels, significantly impacting the mass transfer rate between reactants and products in the electrolysis device. Additionally, the simple surface structure and small area of ​​the electrodes affect the reaction rate per unit area within the electrolysis device. Currently, there are no research reports on the use of non-metallic materials as electrode plates in the field of pure electrolytic hydrogen production.

[0005] Therefore, based on our ongoing research into electrolysis devices and the knowledge our team has accumulated in silicon-based materials, this application seeks to find a technical solution to address the aforementioned technical problems. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide an electrode plate for an electrolysis device and an electrolysis device thereof, which significantly reduces the material cost of the electrode plate while maintaining good mechanical support and sealing functions. At the same time, it reduces the overpotential of the electrochemical reaction products and increases the electrolysis reaction rate per unit area in the electrolysis device, thereby effectively reducing the working voltage for the same electrochemical reaction rate and ultimately significantly increasing the energy conversion efficiency of the electrochemical reaction.

[0007] The technical solution adopted in this invention is as follows:

[0008] An electrode plate for an electrolysis device, wherein the electrolysis device is connected to a DC power supply and injected with an electrolyte to convert electrical energy into chemical energy; characterized in that the electrode plate comprises a silicon-based electrode plate made of doped conductive silicon material; wherein the silicon-based electrode plate is electrically connected to the DC power supply, and at least one surface of the electrode plate is provided with a flow channel, so that the electrolyte is input into the electrolysis device through the silicon-based electrode plate, an electrochemical reaction occurs, and reaction products are output.

[0009] Preferably, the resistivity of the silicon-based electrode plate is not greater than 0.1 ohm-cm, and more preferably 1-30 milliohm-cm; and / or the silicon-based electrode plate is made of 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, and more preferably 0.2-5 mm.

[0010] It should be noted that the silicon-based electrode plate made of crystalline silicon materials (including monocrystalline silicon or polycrystalline silicon) in this application has better thermal conductivity than metals, thereby better conducting and distributing the heat generated in the electrochemical reaction of the electrolysis device using the silicon-based electrode plate provided in this application. At the same time, it makes the electrolysis device using the silicon-based electrode plate provided in this application have better temperature uniformity, reducing the impact of temperature inhomogeneity on the performance and lifespan of the electrolysis device. In addition, the silicon-based electrode plate can not only be fabricated with fine flow channel structures, but also precisely control the consistency of the flow field structure and surface morphology of the silicon-based electrode plate. In subsequent applications, multiple electrolysis units based on silicon-based electrode plates will be stacked to form a multilayer electrolysis device. The performance of each electrolysis unit in the multilayer electrolysis device is more consistent, which is more conducive to increasing the application requirements of the number of electrolysis units in the multilayer electrolysis device, and can further improve the performance and lifespan of the multilayer electrolysis device.

[0011] Preferably, the flow channel comprises a channel structure consisting of staggered grooves and ridges, wherein the width of the grooves is 0.2-5 mm, preferably 0.5-1 mm; the width of the ridges is 0.1-10 mm, preferably 0.2-0.4 mm; the height of the ridges is 0.1-5 mm, preferably 0.12-0.5 mm; and / or the flow channel comprises a porous or textured structure, wherein the pore size of the porous structure or the textured structure characteristic size is 0.1 μm-1000 μm, preferably 0.3 μm-10 μm.

[0012] Preferably, the channel structure is fabricated using an alkaline etching process or an electrochemical etching process; the porous structure or textured structure is fabricated using a liquid-phase method or a gas-phase method; wherein, preferably, the liquid-phase method specifically includes selective etching, electrochemical etching, catalytic etching, etc.; the gas-phase method includes plasma etching, etc.; these processes are all known processes, and various desired channel structures, porous structures, or textured structures can be fabricated according to actual application requirements. While realizing the input of electrolyte into the electrolysis device, the mass transfer rate of reactants and products in the electrochemical reaction and / or the reaction rate on the silicon-based electrode surface are increased by increasing the effective contact area between the catalyst and the electrolyte on the silicon-based electrode plate.

[0013] Preferably, at least a portion of the flow channel is coated with a catalyst for promoting the electrochemical reaction; the catalyst is 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.

[0014] Preferably, the area ratio of the flow channel ranges from 1.2 to 5, more preferably from 1.5 to 3, and even more preferably from 1.7 to 2. The area ratio referred to throughout this application refers to the ratio of the sum of the surface areas of the flow channel exposed to the electrolyte (i.e., 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 flow channel surface within the electrolytic cell. Specifically, the "sum of the surface areas of the flow channel exposed to the electrolyte" and the "area occupied by the flow channel surface within the electrolytic cell" mentioned in this application can be obtained by scanning the electrode plates using a known scanning electron microscope (SEM) to obtain SEM images. By scanning with an electron microscope, the surface area of ​​the flow channel exposed to the electrolyte and the area occupied by the flow channel surface within the electrolytic cell can be measured respectively, thus obtaining the area ratio of the flow channel.

[0015] Preferably, the electrode plate is a bipolar plate; wherein,

[0016] The silicon-based electrode plate is provided with at least an electrolyte connection port, an anode product outlet and a cathode product outlet;

[0017] One surface of the silicon-based electrode plate is provided with an anode flow channel communicating with the anode product outlet, and the other surface is provided with a cathode flow channel communicating with the cathode product outlet.

[0018] The electrolyte connection port is connected to the anode channel and / or the cathode channel.

[0019] Preferably, the electrode plate is a bipolar plate, and the bipolar plate includes at least a first silicon-based electrode plate and a second silicon-based electrode plate stacked together, wherein...

[0020] Each silicon-based electrode plate is provided with at least an electrolyte connection port, an anode product outlet, a cathode product outlet, and a coolant connection port;

[0021] The outer surface of the first silicon-based electrode plate is provided with an anode flow channel communicating with the anode product outlet, and the second silicon-based electrode plate is provided with a cathode flow channel communicating with the cathode product outlet;

[0022] The electrolyte inlet is connected to the anode channel and / or the cathode channel;

[0023] At the same time, a coolant flow channel is formed between the first silicon-based electrode plate and the second silicon-based electrode plate, which is connected to the coolant communication port.

[0024] Preferably, the electrode plate serves as an end anode plate or an end cathode plate; the end anode plate or end cathode plate comprises a silicon-based electrode plate made of doped conductive silicon material, wherein,

[0025] The silicon-based electrode plate is provided with an electrolyte connection port, an anode product outlet, or a cathode product outlet;

[0026] One surface of the silicon-based electrode plate is provided with an anode flow channel communicating with the anode product outlet or a cathode flow channel communicating with the cathode product outlet.

[0027] The electrolyte connection port is connected to the anode channel or the cathode channel.

[0028] Preferably, the electrode plate serves as an end anode plate or an end cathode plate; the end anode plate or end cathode plate comprises at least a first silicon-based electrode plate and a second silicon-based electrode plate stacked together, each silicon-based electrode plate being made of doped conductive silicon material, wherein,

[0029] Each silicon-based electrode plate is provided with at least an electrolyte connection port, an anode product outlet or a cathode product outlet, and a coolant connection port;

[0030] The outer surface of the first silicon-based electrode plate or the second silicon-based electrode plate is provided with an anode flow channel communicating with the anode product outlet or a cathode flow channel communicating with the cathode product outlet;

[0031] The electrolyte inlet is connected to the anode channel or the cathode channel;

[0032] At the same time, a coolant flow channel is formed between the first silicon-based electrode plate and the second silicon-based electrode plate, which is connected to the coolant communication port.

[0033] Preferably, an electrolysis device is connected to a DC power supply and injected with an electrolyte to convert electrical energy into chemical energy, wherein the electrode plates of the electrolysis device are as described above.

[0034] Preferably, the electrolyte is pure water, an alkaline aqueous solution, or an acidic aqueous solution, which electrolyzes water to generate hydrogen and oxygen through an electrochemical reaction.

[0035] Preferably, it includes an anode current collector connected to the positive terminal of a DC power supply, a cathode current collector connected to the negative terminal of a DC power supply, an end anode plate electrically connected to the anode current collector, and an end cathode plate electrically connected to the cathode current collector; a diaphragm or proton exchange membrane or one or more electrolysis units connected in series and / or in parallel are provided between the end anode plate and the end cathode plate; the single electrolysis unit includes a bipolar plate and a diaphragm or proton exchange membrane located on both sides of the bipolar plate.

[0036] Preferably, the electrolysis device is manufactured as a standard product, and assembled into the required electrolysis device module by connecting it in series and / or in parallel with a DC power supply. When the power supply of the DC power supply is insufficient for all electrolysis devices to operate, some electrolysis devices are selectively stopped, so that the remaining electrolysis devices can perform electrolysis normally.

[0037] The working principle and advantages of this invention: Before proposing this invention, the applicant discovered that, in order to achieve good mechanical support and excellent current conduction, heat conduction and heat distribution, reactant and product distribution, etc., the prior art generally considered to use metal electrode plates (especially carbon steel or titanium plates with a thickness of 2-5mm are usually preferred) as electrode plates for water electrolysis devices. The applicant was surprised to find that when silicon wafers are used to make electrodes for silicon-based electrolysis devices, while maintaining good mechanical support and sealing functions, the material and process costs of the electrode plates for electrolysis devices are significantly reduced due to the abundance of silicon material resources and the mature level of silicon wafer processing technology. Moreover, it should be particularly noted that this application proposes to connect the silicon-based electrode plate to a DC power supply, and at the same time, to form a precise and reliable flow field distribution by creating the required precision flow channels on the silicon-based electrode plate, thereby improving the mass transfer rate of reactants and products in the electrolysis device and thus reducing the overpotential of the electrolysis reaction; and to create rich surface morphologies on the silicon-based electrode plate with the flow field, it can effectively increase the contact area between the electrolyte and the electrode plate, thereby reducing the overpotential of the electrochemical reaction. Because this application can reduce the overpotential of the electrochemical reaction at multiple levels, it effectively reduces the operating voltage of the electrochemical reaction, thereby significantly increasing the energy conversion efficiency of the electrochemical reaction. Moreover, compared with the metal-based electrodes of the prior art, this application can also significantly improve the uniformity of the operating temperature of the electrochemical reaction and the consistency between the units in the electrolysis device composed of multiple electrochemical reaction units, thereby improving the electrolysis performance and lifespan of the electrolysis device; Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the bipolar plate structure in Embodiment 1 of the present invention.

[0039] Figure 2 This is a schematic diagram of the end anode plate structure in Embodiment 2 of the present invention;

[0040] Figure 3 This is a schematic diagram of the end cathode plate structure in Embodiment 3 of the present invention;

[0041] Figure 4 This is a schematic diagram of the bipolar plate structure in Embodiment 4 of the present invention.

[0042] Figure 5 This is a schematic diagram of the end anode plate structure in Embodiment 5 of the present invention;

[0043] Figure 6 This is a schematic diagram of the end cathode plate structure in Embodiment 6 of the present invention;

[0044] Figure 7 This is a schematic diagram of the bipolar plate structure in Embodiment 7 of the present invention;

[0045] Figure 8 This is a schematic diagram of the bipolar plate structure in Embodiment 9 of the present invention.

[0046] Figure 9 This is a schematic diagram of the bipolar plate structure in Embodiment 10 of the present invention.

[0047] Figure 10 This is a schematic diagram of the electrode plate mounting structure of the electrolysis device in Embodiment 14 of the present invention.

[0048] Figure 11 This is a schematic diagram of the installation structure of the electrolysis device in Embodiment 14 of the present invention.

[0049] Figure 12 This is a schematic diagram of the electrode plate mounting structure in the electrolysis device in Embodiment 15 of the present invention.

[0050] Figure 13 This is a schematic diagram of the installation structure of the electrolysis device in Embodiment 16 of the present invention.

[0051] Figure 14 This is a SEM image of the textured structure 13 on the silicon-based electrode plate in Example 7 of the specific embodiments of the present invention;

[0052] Figure 15 This is another SEM image of the textured structure 13 on the silicon-based electrode plate in Example 7 of the specific embodiments of the present invention. Detailed Implementation

[0053] This invention discloses an electrode plate for an electrolysis device. The electrolysis device is connected to a DC power supply and injected with an electrolyte to convert electrical energy into chemical energy. The electrode plate includes a silicon-based electrode plate made of doped conductive silicon material. The silicon-based electrode plate is electrically connected to the DC power supply, and at least one surface of the electrode plate is provided with a flow channel (the flow channel is used to transport and distribute the electrolyte or reaction products), so that the electrolyte is input into the electrolysis device through the flow channel on the silicon-based electrode plate to undergo an electrochemical reaction and output reaction products.

[0054] Preferably, in this embodiment, the resistivity of the silicon-based electrode is not greater than 0.1 ohm-cm, more preferably 1-30 milliohm-cm, more preferably 1-10 milliohm-cm, further preferably 1-5 milliohm-cm, and even more preferably 1-3 milliohm-cm; and / or preferably, in this embodiment, the silicon-based electrode is made of crystalline silicon (in terms of crystal type: it may include monocrystalline silicon or polycrystalline silicon, etc.; in terms of doping type: it may include N-type doped crystalline silicon or P-type doped crystalline silicon) or amorphous silicon material (including metallic silicon), preferably made of monocrystalline silicon material, more preferably with amorphous crystal orientation. <111> Crystal orientation, specifically can be <100> Crystal orientation or <110> Crystal orientation or other related <111> Crystal orientations with distinct angles are preferred. <100> Crystal orientation;

[0055] And / or preferably, in this embodiment, the thickness of the silicon-based electrode plate ranges from 0.1 to 10 mm, preferably 0.2 to 5 mm, and more preferably 0.5 to 2 mm; and / or preferably, in this embodiment, the shape of the silicon-based electrode plate can be square, round, or other desired shapes, and this application does not impose specific limitations on its implementation. The substrate of the silicon-based electrode plate used in this application can be a cut silicon wafer, which can be further chemically polished or mechanically polished to improve surface flatness and facilitate subsequent processing steps on the silicon wafer; in implementation, the thickness and shape of the silicon-based electrode plate can also be selected according to the dynamic development level of silicon wafer cutting and processing technology, and this application does not impose any particular limitation on a single range;

[0056] Preferably, in this embodiment, the flow channel includes a channel structure composed of staggered grooves and ridges, wherein the width of the grooves is 0.2-5 mm, preferably 0.5-1 mm; the width of the ridges is 0.1-10 mm, preferably 0.2-0.4 mm; the height of the ridges (i.e., equivalent to the depth of the grooves) is 0.1-5 mm, more preferably 0.1-2 mm, further preferably 0.12-0.5 mm, and even more preferably 0.15-0.5 mm, and / or preferably, in this embodiment, the flow... The channel includes a porous or textured structure. In practice, the porous or textured structure can be fabricated separately on the silicon-based electrode plate, or it can be further fabricated on the surface of the silicon-based electrode plate where the channel structure is located after the channel structure has been set. Preferably, in this embodiment, the pore size of the porous structure or the feature size of the textured structure is 0.1 micrometer to 1000 micrometers, preferably 0.3 micrometers to 10 micrometers. In practical applications, this can enable the electrolysis device to obtain an electrode plate with a fine flow field structure distribution and a high area ratio surface morphology.

[0057] Preferably, in this embodiment, the channel structure is fabricated using an alkaline etching process or an electrochemical etching process. In practice, any known alkaline etching process or any known electrochemical etching process can be used. More preferably, in this embodiment, for silicon-based electrodes made of N-type doped crystalline silicon, it is recommended to use a strong alkaline solution for etching or electrochemical etching; for silicon-based electrodes made of P-type doped crystalline silicon, it is recommended to use an electrochemical etching process. Preferably, in this embodiment, the strong alkaline solution can be an organic or inorganic strong alkaline aqueous solution, and the mass concentration of the strong alkaline solution is recommended to be in the range of 10%-50%, preferably a KOH aqueous solution with a mass concentration of 25-35%. The etching temperature is 50-120℃, preferably 70-85℃ for the alkaline etching process. Of course, in other embodiments, other methods can also be used to process and fabricate the channel structure required in this embodiment. Preferably, in this embodiment, the porous structure or textured structure is fabricated using a liquid phase method or a gas phase method. The liquid phase method includes selective etching, electrochemical etching, catalytic etching, etc.; the gas phase method includes plasma etching, etc. In practice, any known silicon wafer texturing process (which belongs to selective etching in liquid phase method) can be used to texturize the surface of silicon-based plates, or any known process (such as vapor deposition) can be used to create a porous silicon layer (i.e., a porous structure). Due to the texturing process, the area ratio of the silicon-based electrode plate increases, and the electrochemical reaction rate per unit area of ​​the electrode plate surface in the electrolysis device increases. This not only benefits the performance of the electrolysis device but also reduces its cost. Furthermore, the fabrication of a porous silicon layer on the silicon-based electrode plate creates a porous structure on the corresponding surface that allows for fluid flow. This 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 in gaseous form) within the electrode plate channels. This increases the electrochemical reaction rate per unit area in the electrolysis device. At the same time, the porous structure can reduce the hydrophobicity and gas affinity of the electrode plate, thereby reducing the formation of large bubbles in the channels (including the exchange between reactants and reaction products within the channels, if any). This further increases the electrochemical reaction rate and energy conversion efficiency of the electrolysis device.

[0058] Preferably, in this embodiment, a catalyst for promoting the electrochemical reaction is coated on at least a portion of the flow channel (specifically, at least a portion of the channel structure, at least a portion of the porous structure, or at least a portion of the textured surface). The catalyst is a metal-based catalyst or a non-metal-based catalyst. Preferably, in this embodiment, the metal-based catalyst includes noble metal-based catalysts and non-noble metal-based catalysts. The noble metal-based catalyst is selected from any one or more of Ir, Pt, Pd, Au, and Ag. The non-noble metal-based catalyst is selected from any one or more of Fe, Co, Ni, and Al. The non-metal-based catalyst is selected from carbon materials or carbon composite materials. Experiments in this application have confirmed that in the application of alkaline electrolysis devices, the catalysts matched with silicon-based plates include noble metal catalysts, such as Ir and Al alloys, and non-noble metal nickel-based catalysts (that is, catalysts containing nickel Ni, including nickel catalysts or nickel alloy catalysts). The nickel catalyst can specifically be pure electroplated nickel, and the nickel alloy catalyst can be a highly active nickel alloy catalyst, such as Raney nickel, activated nickel sulfide, or N. In practical implementation, the appropriate catalyst, such as i-Mo alloy or activated NiAl, is selected based on specific cost and / or performance requirements. This embodiment does not impose a unique limitation on this. Experiments have confirmed that when the electrode plate provided in this embodiment is provided with a catalyst layer, a diffusion layer is no longer required for the diaphragm or proton exchange membrane in specific applications, further saving structural costs.

[0059] In implementing this application, any known method can be used to coat the catalyst, and this application does not impose any particular restrictions on it. For example, spraying, printing, electroplating, PVD, etc. are preferred. Specifically, when the catalyst is directly coated on the channel structure, electroplating, PVD or other integral deposition coating methods are preferred. When the catalyst is coated on a porous structure, physical coating methods such as spraying and printing are preferred.

[0060] Preferably, in this embodiment, the area ratio of the flow channel is in the range of 1.2-5, more preferably 1.7-2. In practical applications, this can significantly reduce the overpotential required for the electrochemical reaction to occur in the electrolysis device, and increase the reaction rate per unit area. It should be particularly noted that when the flow channel in this embodiment is coated with a catalyst, the activity of the catalyst can be further increased, thereby further reducing the overpotential required for the electrochemical reaction and increasing the reaction rate per unit area in the electrolysis device.

[0061] It should be noted that different bipolar plates, end anode plates, or end cathode plates can be fabricated according to the electrode plate scheme provided in the above embodiments and in combination with the specific requirements of the electrolysis device. This embodiment does not impose a unique limitation on this.

[0062] Preferably, this embodiment proposes an electrolysis device that is connected to a DC power supply and injected with an electrolyte to convert electrical energy into chemical energy. The electrode plates of the electrolysis device are based on the above-mentioned electrode plates.

[0063] Preferably, in this embodiment, the electrolyte is pure water, an alkaline aqueous solution, or an acidic aqueous solution, and water is electrolyzed to generate hydrogen and oxygen through an electrochemical reaction; of course, a suitable electrolyte can also be selected according to actual needs to prepare the desired reaction products.

[0064] Preferably, in this embodiment, the electrolysis device includes an anode plate connected to the positive terminal of a DC power supply, a cathode plate connected to the negative terminal of a DC power supply, an end anode plate electrically connected to the anode plate, and an end cathode plate electrically connected to the cathode plate; a diaphragm or proton exchange membrane or one or more electrolysis units connected in series and / or in parallel are provided between the end anode plate and the end cathode plate; a single electrolysis unit includes a bipolar plate and a diaphragm or proton exchange membrane located on both sides of the bipolar plate.

[0065] It should also be noted that the electrode structure provided in this embodiment can be applied to various types of electrolysis devices according to actual needs, including but not limited to: alkaline electrolysis devices (also known as alkaline electrolyzers), PEM (an abbreviation for "Proton Exchange Membrane") electrolysis devices (also known as PEM electrolyzers), and of course, it can also be applied to other types of electrolysis devices with similar needs. These are all conventional application choices that can be made by those skilled in the art based on the scope of this application, and the embodiments of this application will not be listed one by one.

[0066] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0067] Example 1: Please refer to Figure 1 As shown, an electrode plate of a water electrolysis device, the electrode plate serving as a bipolar plate, includes a silicon-based electrode plate 10 made of doped conductive silicon material; wherein...

[0068] The silicon-based electrode 10 is respectively provided with an electrolyte connection port, an anode product outlet and a cathode product outlet;

[0069] The lower surface of the silicon-based electrode plate 10 is provided with an anode flow channel 11 that communicates with the anode product outlet, and the upper surface of the plate is provided with a cathode flow channel 12 that communicates with the cathode product outlet.

[0070] The electrolyte connection port is connected to the anode channel 11; in other embodiments, as a subpreferred example, it may also be connected to the cathode channel 12, or it may be connected to both the anode channel 11 and the cathode channel 12 simultaneously.

[0071] In this embodiment, during actual fabrication, a 1.5 mm thick, circular-shaped N-type doped single-crystal silicon material was selected. <100> A silicon wafer made with a crystal orientation is used as the substrate of the silicon-based electrode 10, with a resistivity of 2.5 milliohms.

[0072] Selective etching of two surfaces of a silicon wafer with a mass concentration of 30% KOH aqueous solution is used to obtain silicon-based electrode plates with channel structures on the upper and lower surfaces respectively. The channel structure located on the upper surface of the silicon-based electrode plate 10 is used as the cathode channel 12, and the channel structure located on the lower surface of the silicon-based electrode plate 10 is used as the anode channel 11.

[0073] In specific implementation, the channel structure of the cathode channel 12 and the channel structure of the anode channel 11 can be set to be the same or different; and the channel structure in the same electrode channel (e.g., anode channel 11, cathode channel 12) can also be set to be arranged in alternating coarse and fine channel units, which can obtain better fluid transport efficiency, thereby increasing the efficiency of electrochemical reaction, and also reducing the power consumption of driving the flow of reactants and products in the electrolysis device.

[0074] In this embodiment, the groove 11a of the anode channel 11 has a width of 0.8 mm and a depth of 0.2 mm, and the ridge 11b has a width of 0.4 mm. The channel structure of the cathode channel 12 is the same as that of the anode channel 11, with a groove 12a having a width of 0.8 mm and a depth of 0.15 mm, and a ridge 12b having a width of 0.4 mm. The electrolyte connection port, the anode product outlet, and the cathode product outlet are fabricated on the silicon wafer using laser technology or other processes. These two steps can be performed in any order according to actual needs.

[0075] It should be noted that, in order to achieve the connection effect between the electrolyte connection port, the anode product outlet and the cathode product outlet and their corresponding flow channels, those skilled in the art will know that it is necessary to make a flow guiding structure at a suitable position on the outer periphery of the silicon wafer to introduce the electrolyte, anode product and cathode product into and out of the electrolysis device from the electrode flow field, respectively. Specifically, preferably, the flow guiding structure can be made at the same time as the channel structure. This embodiment will not elaborate on this further.

[0076] In this embodiment, a single silicon wafer is used as the substrate of the silicon-based electrode plate 10. When applied to a PEM water electrolysis device, no thin film needs to be coated on the silicon-based electrode plate. After prolonged electrolysis for hydrogen production, no changes were observed in the electrode plate's electrical, mechanical, and chemical properties. In this embodiment, cooling is achieved directly through the electrolyte connected to the anode channel. Therefore, it is recommended that the electrolyte flow rate be set relatively high, requiring a larger electrolyte driving power.

[0077] Example 2: Please refer to Figure 2 As shown, an electrode plate of an electrolysis device serves as an end anode plate; the end anode plate includes a silicon-based electrode plate 20 made of doped conductive silicon material, wherein...

[0078] The silicon-based electrode 20 is provided with an electrolyte connection port and an anode product outlet;

[0079] The lower surface of the silicon-based electrode plate 20 is provided with an anode flow channel 21 that communicates with the anode product outlet;

[0080] The electrolyte inlet is connected to the anode flow channel 21;

[0081] The remaining implementation schemes of this embodiment 2 are the same as those of embodiment 1.

[0082] Example 3: Please refer to Figure 3 As shown, an electrode plate of an electrolysis device, preferably, is an end cathode plate; the end cathode plate includes a silicon-based electrode plate 30 made of doped conductive silicon material, wherein...

[0083] The silicon-based electrode 30 is provided with an electrolyte connection port and a cathode product outlet;

[0084] The upper surface of the silicon-based electrode 30 is provided with a cathode flow channel 31 that communicates with the cathode product outlet;

[0085] The remaining implementation schemes of this embodiment 3 are the same as those of embodiment 1.

[0086] Example 4: Please refer to Figure 4 As shown, an electrode plate of an electrolysis device, the electrode plate serving as a bipolar plate, the bipolar plate comprising a first silicon-based electrode plate 41 and a second silicon-based electrode plate 42 stacked integrally, wherein...

[0087] Each silicon-based electrode plate 41, 42 is respectively provided with an electrolyte connection port, an anode product outlet, a cathode product outlet and a coolant connection port;

[0088] The outer surface of the first silicon-based electrode plate 41 is provided with an anode flow channel 41a that communicates with the anode product outlet, and the second silicon-based electrode plate 42 is provided with a cathode flow channel 42a that communicates with the cathode product outlet.

[0089] The electrolyte inlet is connected to the anode flow channel 41a;

[0090] At the same time, a coolant flow channel 43 is formed between the first silicon-based electrode plate 41 and the second silicon-based electrode plate 42, which is connected to the coolant communication port;

[0091] The remaining implementation schemes of this embodiment 4 are the same as those of embodiment 1; it should be noted that the coolant connection port can also be made by laser process or other processes. In order to achieve the connection effect between the coolant connection port and its corresponding coolant flow channel 43, those skilled in the art know that a flow guiding structure needs to be made at a suitable position on the outer periphery of the silicon wafer; in this embodiment, the first silicon base plate 41 and the second silicon base plate 42 can be directly fixed and stacked by using a sealing material (such as the sealing adhesive layer 44 used in this embodiment). In other embodiments, a fixed stacking effect can also be achieved by high-temperature sintering of metal materials.

[0092] The bipolar plate provided in this embodiment is equipped with a coolant flow channel 43 (the coolant can be water, or other suitable coolants). The heat generated during the electrochemical reaction is carried away by the coolant flow channel 43. The flow rate of the electrolyte only needs to meet the requirements of the electrochemical reaction. Therefore, the flow rate of the electrolyte can be set to a low level, which can further save the energy consumed in transporting the electrolyte.

[0093] Example 5: Please refer to Figure 5 As shown, an electrode plate of an electrolysis device serves as an end anode plate; the end anode plate includes a first silicon-based electrode plate 51 and a second silicon-based electrode plate 52 stacked integrally, wherein...

[0094] Each silicon-based electrode plate 51, 52 is respectively provided with an electrolyte connection port, an anode product outlet and a coolant connection port;

[0095] The outer surface of the first silicon-based electrode 51 is provided with an anode flow channel 51a that communicates with the anode product outlet;

[0096] The electrolyte inlet is connected to the anode flow channel 51a;

[0097] Meanwhile, a coolant flow channel 53 is formed between the first silicon-based electrode plate 51 and the second silicon-based electrode plate 52, which is connected to the coolant connection port;

[0098] The remaining implementation schemes of this embodiment 5 are the same as those of embodiment 4.

[0099] Example 6: Please refer to Figure 6 As shown, an electrode plate of an electrolysis device serves as an end cathode plate; the end cathode plate includes a first silicon-based electrode plate 61 and a second silicon-based electrode plate 62 stacked integrally, wherein...

[0100] Each silicon-based electrode plate 61, 62 is provided with an electrolyte connection port, a cathode product outlet and a coolant connection port;

[0101] The outer surface of the second silicon-based electrode 62 is provided with a cathode flow channel 62a that communicates with the cathode product outlet;

[0102] Meanwhile, a coolant flow channel 63 is formed between the first silicon-based electrode plate 61 and the second silicon-based electrode plate 62, which is connected to the coolant connection port.

[0103] Example 7: Please refer to Figure 7 As shown, the remaining technical solutions of this embodiment 7 are the same as those of embodiment 1, except that the upper and lower surfaces of the silicon-based electrode plate 10 with the channel structure are subjected to a texturing process, and a texturing structure 13 is further fabricated on the basis of the channel structure (please refer to further details). Figure 14 and Figure 15 (As shown).

[0104] Example 8: The remaining technical solutions of Example 8 are the same as those of Example 7, except that a porous silicon layer is further fabricated on the textured structure 13 by vapor phase method.

[0105] Example 9: The remaining technical solutions of Example 9 are the same as those of Example 7, except that, please refer to [link / reference needed]. Figure 8 As shown, a catalyst layer 14 is further coated on the porous structure 13, specifically an activated nickel sulfide layer.

[0106] Example 10: The remaining technical solutions of Example 10 are the same as those of Example 1, except that, please refer to [link / reference needed]. Figure 9 As shown, a porous silicon layer with a porous structure is deposited on two surfaces of a silicon wafer. Preferably, in order to facilitate the flow field effect of the porous structure and the mechanical stability of the electrode, in this embodiment, grooves 71 and 72 are pre-fabricated in the middle area of ​​the upper and lower surfaces of the silicon wafer (any known processing technology can be used), and then a porous silicon layer (not shown) is obtained in the grooves 71 and 72 by liquid phase method or gas phase method.

[0107] Example 11: The remaining technical solutions of Example 11 are the same as those of Example 1, except that a catalyst layer is further coated on the channel structure, specifically an activated nickel sulfide layer.

[0108] Example 12: An electrode plate for an electrolysis device, using the end anode plate provided in Example 2, wherein the lower surface of the silicon-based electrode plate with a channel structure is texturized, and a textured structure is further fabricated on the basis of the channel structure, and then a catalyst layer, specifically an activated nickel sulfide layer, is further coated on the textured structure.

[0109] Example 13: An electrode plate for an electrolysis device, using the end cathode plate provided in Example 3, wherein the upper surface of the silicon-based electrode plate with a channel structure is texturized, and a textured structure is further formed on the basis of the channel structure, and then a catalyst layer, specifically an activated nickel sulfide layer, is further coated on the textured structure.

[0110] Example 14: An electrolysis device, connected to a DC power supply and injected with electrolyte, converts electrical energy into chemical energy; please refer to [reference needed]. Figure 10 and Figure 11 As shown, the electrolysis device includes an anode current collector 83a connected to the positive terminal of a DC power supply, a cathode current collector 83b connected to the negative terminal of a DC power supply, an end anode plate 84 electrically connected to the anode current collector 83a, and an end cathode plate 85 electrically connected to the cathode current collector 83b. To achieve a safe and reliable installation connection, the upper and lower ends of the electrolysis device are also provided with an anode end plate 81 and a cathode end plate 82, 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 to ensure electrical insulation between the anode current collector 83a and the cathode current collector 83b.

[0111] In this embodiment, the end anode plate 84 adopts the end anode plate provided in Embodiment 2, and the end cathode plate 85 adopts the end cathode plate provided in Embodiment 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 the two are sealed and stacked by a sealing member 87. In order to further improve the working efficiency, an anode diffusion layer 87a and a cathode diffusion layer 87b are further provided on both sides of the proton exchange membrane 86, and 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, etc. Those skilled in the art can combine and apply them according to actual needs.

[0112] Preferably, in this embodiment 14, the electrolyte is pure water, and water is electrolyzed to generate hydrogen and oxygen through an electrochemical reaction in the electrolysis device, wherein hydrogen is the cathode product and oxygen is the anode product.

[0113] Example 15: Please refer to Figure 12 As shown, an electrolysis device uses the end anode plate provided in Example 12 as the end anode plate 91, and the end cathode plate provided in Example 13 as the end cathode plate 92. A diaphragm 93 (which can be any known diaphragm structure) is provided between the end anode plate 91 and the end cathode plate 92. The electrolyte is an aqueous NaOH solution. An alkaline electrolysis device is obtained by assembling the device using a known assembly method.

[0114] Example 16: The remaining technical solutions of Example 16 are the same as those of Example 14. Please refer to Example 14 for details. Figure 13 As shown, in the electrolysis device provided in this embodiment 16, an electrolysis unit is provided between the end anode plate 84 and the end cathode plate 85; the electrolysis unit includes a bipolar plate 89a (specifically, the bipolar plate provided in embodiment 1 is used, and in other embodiments, the bipolar plate provided in embodiment 4 can also be used) and a proton exchange membrane 89b located on both sides of the bipolar plate (similarly, a diffusion layer and catalyst can be further provided on both sides of the proton exchange membrane 89b as in embodiment 14), and the PEM electrolysis device is assembled; in other embodiments, a diaphragm can be provided on both sides of the bipolar plate according to actual needs; or two or more electrolysis units connected in series and / or in parallel can be provided between the end anode plate and the end cathode plate; wherein, when adjacent electrolysis units are connected in series and / or in parallel, a diaphragm or a proton exchange membrane can be shared.

[0115] It should also be noted that in subsequent applications, the electrolysis device provided in Embodiment 16 can be manufactured as a standard product. Various specifications of electrolysis device modules can be assembled by connecting them in series and / or in parallel with a DC power supply, and by connecting the electrolyte, cathode gas, and anode gas in parallel. Different electrolysis device systems can be flexibly assembled according to the size of the connected DC power supply. More preferably, when the power supply is insufficient for all electrolysis devices to operate, some electrolysis devices can be selectively stopped, allowing the remaining devices to continue electrolysis normally. It should be specifically pointed out that "continuously operating electrolysis" here means that these remaining electrolysis devices operate at their optimal operating point, where the optimal operating point means operating with the highest energy conversion efficiency at their optimal operating current density and voltage. This ensures that the entire electrolysis device module system produces hydrogen at the highest rate. This electrolysis device system can operate with maximum efficiency when powered by intermittent photovoltaic and wind power systems.

[0116] To verify the technical effects achieved by this application, the applicant conducted the following tests on embodiments 15 and 16:

[0117] The DC power supply voltage is 1.75V per electrolysis unit; the operating temperature range of the electrolysis unit is 60-80℃; the operating voltage range of the electrolysis unit is 1.5V-2.4V per electrolysis unit.

[0118] The flow rate of the produced hydrogen was then measured according to the standard GB / T 19774-2005; the results are as follows:

[0119] The output hydrogen flow rate in Example 15 was 0.09 Nm³. 3 / h, the corresponding energy conversion efficiency is: 84.6%;

[0120] The output hydrogen flow rate in Example 16 was 0.2 Nm³. 3 The energy conversion efficiency corresponding to / h is 84.6%.

[0121] It should be particularly noted that, under the condition of a DC power supply voltage of 1.75V per electrolysis unit, the electrolysis device provided in this application achieves an energy conversion efficiency of 84.6%, which is quite remarkable for the field of electrolysis and represents a significant advancement.

[0122] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0123] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An electrolytic device, which is connected to a direct current power source and injects electrolyte, converts electrical energy into chemical energy, characterized in that, The electrode plate of the electrolytic device comprises a silicon-based electrode plate made of doped conductive silicon material; wherein the silicon-based electrode plate is connected to a direct current power supply, and at least one surface of the silicon-based electrode plate is provided with a flow channel, so that the electrolyte is input into the electrolytic device through the silicon-based electrode plate, electrochemical reaction occurs, and reaction products are output; The resistivity of the silicon-based electrode plate is not greater than 0.1 ohm centimeter; the silicon-based electrode plate is made of single crystal silicon or polycrystalline silicon material; and the thickness of the silicon-based electrode plate ranges from 0.1 to 10 millimeters. The flow channel comprises a channel structure composed of staggered grooves and ridges, wherein the width of the groove is 0.2-5 millimeters; the width of the ridge is 0.1-10 millimeters; the height of the ridge is 0.1-5 millimeters; and / or the flow channel comprises a porous pore or a velvet structure, and the pore size of the porous pore or the characteristic size of the velvet structure is 0.1-1000 micrometers.

2. The electrolytic device of claim 1, wherein The resistivity of the silicon-based electrode plate is 1-30 milliohms centimeter.

3. The electrolytic device of claim 1, wherein The silicon-based electrode plate is made of single crystal silicon material.

4. The electrolytic device of claim 1, wherein The thickness of the silicon-based electrode plate ranges from 0.2 to 5 millimeters.

5. The electrolytic device of claim 1, wherein The width of the groove is 0.5-1 millimeter.

6. The electrolytic device of claim 1, wherein The width of the ridge is 0.2-0.4 millimeter.

7. The electrolytic device of claim 1, wherein The height of the ridge is 0.12-0.5 millimeter.

8. The electrolytic device of claim 1, wherein, The pore size of the porous pore or the characteristic size of the velvet structure is 0.3-10 micrometers.

9. The electrolytic device of claim 1, wherein, The channel structure is made by an alkali etching process or an electrochemical etching process; and the porous pore structure or the velvet structure is made by a liquid phase method or a gas phase method.

10. The electrolytic device of claim 1, wherein A catalyst for promoting electrochemical reaction is coated on at least part of the flow channel; the catalyst is a metal-based catalyst or a non-metal-based catalyst.

11. The electrolytic device of claim 10, wherein, The catalyst is an iridium-based catalyst, a platinum-based catalyst, a nickel catalyst or a nickel alloy catalyst.

12. The electrolytic device of claim 1, wherein, The area ratio of the flow channel ranges from 1.2 to 5.

13. The electrolytic device of claim 12, wherein, The area ratio of the flow channel ranges from 1.5 to 3.

14. The electrolytic device of claim 12, wherein, The area ratio of the flow channel ranges from 1.7 to 2.

15. The electrolysis device according to one of claims 1 to 14, characterized in that The electrode plate serves as a bipolar plate; wherein, The silicon-based electrode plate is respectively provided with an electrolyte communication port, an anode product outlet and a cathode product outlet; One surface of the silicon-based electrode plate is provided with an anode flow channel in communication with the anode product outlet, and the other surface is provided with a cathode flow channel in communication with the cathode product outlet; The electrolyte communication port is in communication with the anode flow channel and / or the cathode flow channel.

16. The electrolysis device according to one of claims 1 to 14, characterized in that The electrode plate serves as a bipolar plate, and the bipolar plate comprises at least a first silicon-based electrode plate and a second silicon-based electrode plate stacked together, wherein, Each silicon-based electrode plate is respectively provided with an electrolyte communication port, an anode product outlet, a cathode product outlet and a cooling liquid communication port; The outer surface of the first silicon-based electrode plate is provided with an anode flow channel in communication with the anode product outlet, and the second silicon-based electrode plate is provided with a cathode flow channel in communication with the cathode product outlet; The electrolyte communication port is in communication with the anode flow channel and / or the cathode flow channel; Meanwhile, a cooling liquid flow channel in communication with the cooling liquid communication port is formed between the first silicon-based electrode plate and the second silicon-based electrode plate.

17. The electrolysis device according to one of claims 1 to 14, characterized in that The electrode plate serves as an end anode plate or an end cathode plate; the end anode plate or the end cathode plate comprises a silicon-based electrode plate made of doped conductive silicon material, wherein, The silicon-based polar plate is provided with an electrolyte communication port, an anode product outlet or a cathode product outlet; One surface of the silicon-based polar plate is provided with an anode flow channel in communication with the anode product outlet or a cathode flow channel in communication with the cathode product outlet; The electrolyte communication port is in communication with the anode flow channel or the cathode flow channel.

18. The electrolytic device according to any one of claims 1 to 14, wherein The polar plate serves as an end anode plate or an end cathode plate; the end anode plate or the end cathode plate comprises at least a first silicon-based polar plate and a second silicon-based polar plate stacked into one body, each silicon-based polar plate is made of doped conductive silicon material, wherein, Each silicon-based polar plate is provided with at least an electrolyte communication port, an anode product outlet or a cathode product outlet and a cooling liquid communication port respectively; An outer surface of the first silicon-based polar plate or the second silicon-based polar plate is provided with an anode flow channel in communication with the anode product outlet or a cathode flow channel in communication with the cathode product outlet; The electrolyte communication port is in communication with the anode flow channel or the cathode flow channel; A cooling liquid flow channel in communication with the cooling liquid communication port is formed between the first silicon-based polar plate and the second silicon-based polar plate.

19. The electrolytic device of claim 1, wherein, The electrolyte is pure water or an alkaline or acidic aqueous solution, and hydrogen and oxygen are generated by electrolysis of water through an electrochemical reaction.

20. The electrolytic device of claim 1, wherein, The electrolysis device comprises an anode current collector plate connected with a positive pole of a direct current power supply, a cathode current collector plate connected with a negative pole of the direct current power supply, an end anode plate in electrical contact with the anode current collector plate, and an end cathode plate in electrical contact with the cathode current collector plate; a diaphragm or one or more electrolysis units in series and / or parallel connection is arranged between the end anode plate and the end cathode plate; each electrolysis unit comprises a bipolar plate and diaphragms arranged on both sides of the bipolar plate.

21. The electrolytic device of claim 1, wherein, The electrolysis device is made into a standard product, and a required electrolysis device module is assembled by series and / or parallel connection of direct current power supplies; when the power supply of the direct current power supply is insufficient for the operation of all electrolysis devices, some electrolysis devices are selectively stopped to work, so that the remaining electrolysis devices normally perform electrolysis work.

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