Bubble-free interface optimization electrolysis cell system

Abstract

The invention belongs to the technical field of green hydrogen energy production, and particularly relates to a bubble-free interface optimization electrolytic bath system. The electrolytic bath comprises a bath body, the bath body is provided with a hydrogen channel, an oxygen channel, a liquid inlet hole and a liquid outlet hole, the hydrogen channel and the oxygen channel are located on the upper portion of the bath body, a diaphragm is arranged in the bath body, an anode chamber and a cathode chamber are arranged between the two sides of the diaphragm and the bath body respectively, the anode chamber is communicated with the oxygen channel, and the cathode chamber is communicated with the hydrogen channel; an anode plate and a cathode plate are respectively arranged in the anode chamber and the cathode chamber; the middle part of the diaphragm covers the electrode, and the periphery of the diaphragm exceeds the periphery of the electrode; and the part, exceeding the periphery of the electrode, of the diaphragm extends into the liquid inlet channel and is provided with micropores, and the pore diameter of the micropores is 1-5 microns. According to the electrolytic cell, the performance limit of a traditional alkaline electrolytic cell is broken through, the efficient range is increased to 93% or above, the efficiency limit existing in the traditional electrolytic process is effectively relieved, and the cost burden of hydrogen production is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of green hydrogen energy production, and specifically relates to a bubble-free interface optimized electrolyzer system. Background Art

[0002] With the urgent need for the development of renewable energy and clean energy technology, the optimization of efficiency and economy of hydrogen production by alkaline water electrolysis as a key link in the energy conversion chain has increasingly become the focus of scientific research and industry. In recent years, the research and development trends in this field have mainly focused on two key directions:

[0003] 1. Gas management and efficiency improvement: Researchers are committed to optimizing the fine control of gas evolution during the electrolysis process, aiming to reduce the barrier effect caused by bubbles, thereby improving the current transmission efficiency and enhancing the overall performance of the system. This research involves a full range of innovations from fluid dynamics to electrode structure, reflecting the scientific research community's unremitting pursuit of reducing ohmic losses and increasing current density. Although significant efficiency improvement potential has been demonstrated under laboratory conditions, how to efficiently scale up these innovations without sacrificing long-term operational stability remains a key challenge in the transition to actual industrial production.

[0004] 2. High-performance materials and structural innovation: The rapid development of materials science has brought innovative opportunities to electrolyzer technology, especially the development of new electrode materials and catalytic systems. Through nano-engineering, composite material design and the application of innovative catalysts, the aim is to enhance the reactivity of the electrode surface, promote the effective release of gas and reduce energy loss. Although these cutting-edge materials and technologies have shown great application potential, they still need to solve complex problems such as cost control, feasibility of large-scale production processes and long-term reliability verification during the industrialization process. Summary of the invention

[0005] The present invention proposes a bubble-free interface optimized electrolyzer system, which not only reconstructs the efficiency limit in theory, but also demonstrates its economy and environmental friendliness in large-scale applications in practice, providing technical support for the development of green hydrogen energy.

[0006] The present invention specifically provides the following technical solutions:

[0007] The present invention provides a bubble-free interface optimized electrolytic cell, comprising:

[0008] The tank body is provided with a hydrogen channel, an oxygen channel, a liquid inlet channel and a liquid outlet channel; the hydrogen channel and the oxygen channel are located at the upper part of the tank body.

[0009] As an implementation manner, the position of the liquid inlet channel is higher than the position of the liquid outlet channel, and the liquid outlet channel is located at the lower part of the tank body.

[0010] A diaphragm is provided in the tank body, and an anode chamber and a cathode chamber are provided on both sides of the diaphragm and between the tank body, respectively. The anode chamber is connected to the oxygen channel, and the cathode chamber is connected to the hydrogen channel; electrodes are provided in both the anode chamber and the cathode chamber, specifically, an anode plate is provided in the anode chamber, and a cathode plate is provided in the cathode chamber. This arrangement allows the oxygen generated in the anode chamber to be separated through the oxygen channel, and the hydrogen generated in the cathode chamber to be separated through the hydrogen channel. The diaphragm is fitted with the electrode, the middle part of the diaphragm covers the electrode and the periphery of the diaphragm exceeds the periphery of the electrode. In addition, the portion of the diaphragm that exceeds the periphery of the electrode extends into the liquid inlet channel and is provided with micropores, and the portion of the middle part of the diaphragm that covers the electrode is not provided with holes. The provision of micropores on the diaphragm in the present invention allows the portion of the diaphragm that exceeds the periphery of the electrode to diffuse faster to the electrolyte after absorbing the electrode liquid. However, the portion of the middle part of the diaphragm that covers the electrode is not provided with holes, so as to maintain a seal and prevent gas exchange between the anode chamber and the cathode chamber.

[0011] As an implementation mode, the pore size of the micropores is 1 to 5 μm.

[0012] As an embodiment, the tank body includes end plates, and a pole plate is arranged between the end plates, and the pole plates are at least two. The pole plate and the upper part of one of the end plates are both provided with oxygen holes and hydrogen holes, the oxygen holes are connected to form an oxygen channel, and the hydrogen holes are connected to form a hydrogen channel.

[0013] The material of the electrolytic cell body (other components except electrodes and diaphragms) of the present invention is a composite material with excellent corrosion resistance and electrical conductivity to ensure long-term stable operation. Specifically, the cell body uses 316L stainless steel plate as the substrate, and through mechanical processing and chemical cleaning, ensure that the surface is flat and free of impurities. Using chemical vapor deposition (CVD) technology, a layer of graphene coating is evenly coated on the surface of the stainless steel substrate, and the thickness is controlled at 1-2μm. A layer of 5-10μm thick PTFE film is coated on the surface of the graphene coating by spraying or dipping. In the composite material, 10%-40% of carbon fibers (the amount of carbon fibers is preferably 15%) are evenly distributed by compression molding to enhance the mechanical properties of the material.

[0014] As an embodiment, a stepped groove is provided on one or both sides of the electrode plate, the electrode card is arranged on the first step close to the bottom of the stepped groove, and an air channel connected to the oxygen hole or the hydrogen hole is provided on the wall of the stepped groove. An anode chamber or a cathode chamber is formed between the portion of the diaphragm that fits the electrode and the stepped groove, and a gas storage chamber is formed between the electrode and the bottom of the stepped groove. The gas generated by the reaction between the electrode and the electrolyte is separated in sequence from the gas storage chamber, the air channel, the oxygen hole or the hydrogen hole.

[0015] As an embodiment, the end plate is provided with a liquid inlet hole and a liquid outlet hole, and the electrode plate is provided with a guide hole, the guide hole is arranged around the periphery of the stepped groove, and the liquid inlet hole corresponds to the upper end of the guide hole. The periphery of the diaphragm extends into the guide hole and a gap is left between the outer wall of the guide hole, and the diaphragm does not block the oxygen channel and the hydrogen channel. The liquid inlet hole and the guide hole form a liquid inlet channel, and the liquid outlet hole and the guide hole form a liquid outlet channel. The electrolyte enters the guide hole through the liquid inlet hole, and the diaphragm located in the guide hole absorbs the electrolyte and diffuses to the middle of the diaphragm and contacts and reacts with the electrode. In addition, due to the effect of gravity, most of the electrolyte will gather in the lower part of the trough body, and the lower part of the diaphragm (the part beyond the periphery of the electrode) absorbs the electrolyte and diffuses to the middle of the diaphragm and contacts and reacts with the electrode. The gap between the outer periphery of the diaphragm and the outer side wall of the flow guide hole is to allow the electrolyte to enter the electrode chamber on the side away from the liquid inlet hole from the electrode chamber on the side close to the liquid inlet hole, thereby forming a liquid inlet channel, or to allow the electrolyte to enter the electrode chamber on the side close to the liquid outlet hole from the electrode chamber on the side away from the liquid outlet hole, thereby forming a liquid outlet channel. Furthermore, the outer side wall of the flow guide hole is higher than the outer periphery of the stepped groove, which can not only stabilize the diaphragm, but also meet the sealing requirements of the groove body. In a further embodiment, the flow guide hole is an annular structure with a disconnected upper portion, and the oxygen hole and the hydrogen hole are located at the annular disconnection of the flow guide hole.

[0016] The sealing of the tank body can be achieved not only by designing the depth of the step grooves and the guide holes on the electrode plate, but also by setting a spacer on one side of the electrode. The size and shape of the spacer are consistent with the electrode plate. The spacer is also provided with oxygen holes, hydrogen holes, and guide holes. The middle of the spacer is also provided with an electrode clamping hole for clamping the electrode. As a preferred embodiment, the spacer is set on one side of the cathode plate for clamping the cathode plate.

[0017] As an embodiment, the anode plate has a mesh structure, and the preparation method of the anode plate is as follows: the NiFeOOH electrocatalyst is uniformly coated on the Ni mesh by the electrodeposition technology. The mesh structure anode plate is placed at a certain height above the electrolyte surface to ensure that the electrolyte absorbed by the diaphragm can be spontaneously transmitted along the electrode surface through capillary action and surface tension to form a uniform ultra-thin liquid film. The electrode material is selected from the Ni mesh with high catalytic activity, and the electrochemical reaction rate is good.

[0018] The cathode plate uses a gas diffusion layer as a cathode substrate, and after cleaning and drying, a coating material is coated. The coating material is prepared by dispersing a mixture of 80wt% graphene powder and 20wt% platinum nanoparticles with a particle size of ≤5nm in a dispersion medium. The dispersion medium is prepared by a mixed solvent of deionized water and anhydrous ethanol in a volume ratio of 1:1.

[0019] The preparation method of the diaphragm comprises: using oxygen plasma to perform hydrophilic enhancement treatment on the surface of the polyethersulfone diaphragm, and performing corrosion resistance enhancement treatment on the PES diaphragm.

[0020] The present invention also provides a bubble-free interface optimization electrolytic cell system, which includes the electrolytic cell, wherein the two end plates of the electrolytic cell are provided with a liquid inlet hole and a liquid outlet hole, the two liquid inlets of the electrolytic cell are connected to the liquid inlet tank through a liquid inlet pipe, the liquid inlet tank is filled with alkali solution and pure water, and the two ends of the electrolytic cell are provided with a liquid level sensor, and the liquid inlet pipe is provided with a pump and an automatic regulating valve; the two liquid outlet holes of the electrolytic cell are connected through a circulation pipe, and the circulation pipe is provided with a pump, a pipe heater, a temperature detector and a concentration detector. The liquid level sensor is used to monitor and adjust the electrolyte level in real time to ensure that the electrode is always maintained above the electrolyte surface, and at the same time, a sufficient liquid column height is maintained to drive the liquid flow by surface tension. Specifically, the liquid level sensor is installed at appropriate positions on both sides of the electrolytic cell to ensure that the change of the electrolyte level can be fully monitored; the sensor is connected to the controller to collect liquid level data in real time. An electric regulating valve is installed on the liquid inlet pipe of the electrolytic cell to ensure that the valve opening can be quickly adjusted according to the data fed back by the liquid level sensor; the regulating valve is connected to the controller to receive control instructions. Control system configuration: Use embedded controller or PLC to implement PID control algorithm. The control program can adjust the action of the electric regulating valve in real time according to the data of the liquid level sensor to ensure that the electrolyte level is stable near the set value.

[0021] Among them, (1) Liquid level sensor: Use high-precision liquid level sensors, such as ultrasonic liquid level sensors or optical liquid level sensors. These sensors have the advantage of non-contact measurement and can accurately detect the liquid level changes in the electrolytic cell in real time. The liquid level sensors are installed on both sides of the electrolytic cell and can comprehensively monitor the changes in the electrolyte level to ensure the accuracy and reliability of the data.

[0022] (2) Regulating valve: The electric regulating valve is characterized by fast response speed and high regulation accuracy. It can quickly adjust the valve opening according to the data fed back by the liquid level sensor. When the liquid level sensor detects that the liquid level is lower than the set value, the regulating valve will open and add electrolyte (pure water or alkali solution) to the electrolytic cell until the liquid level returns to the set value; conversely, when the liquid level is too high, the regulating valve will close or reduce the amount of replenishment to maintain a stable liquid level.

[0023] (3) Control system: Using intelligent control algorithms, such as PID (proportional-integral-differential) control algorithms, combined with data from the liquid level sensor, to adjust the action of the automatic regulating valve in real time to ensure that the electrolyte level is always in the optimal state. The control logic is implemented through an embedded controller or PLC (programmable logic controller) to ensure that the system can respond quickly and accurately adjust the liquid level.

[0024] The relevant working principle of the electrolytic cell of the present invention:

[0025] Surface tension-driven bubble-free transport: When current passes through the electrode, since the electrode is located above the electrolyte surface, the gas generated by the electrolysis reaction cannot directly gather on the electrode surface to form bubbles, but is guided by surface tension to the oxygen channel or hydrogen channel above the electrolyzer. The presence of the ultra-thin liquid film on the electrode surface greatly promotes mass transfer efficiency, avoids bubble obstruction, and improves the continuity and stability of the electrochemical reaction.

[0026] High-efficiency electrolysis: Thanks to the unique electrode structure and electrolyte level management, the electrolysis process is carried out in an almost bubble-free environment, reducing energy loss and making the hydrogen and oxygen gas separation purer, thereby increasing the electrolysis efficiency to more than 93%.

[0027] Liquid level management: The liquid level control system in the electrolytic cell system can dynamically adjust the electrolyte level according to the electrolysis rate to ensure the optimal liquid film thickness and transmission efficiency, while adapting to the electrolysis requirements under different working conditions to achieve an efficient and stable adaptive electrolysis process.

[0028] The characteristics of the electrolytic cell of the present invention are:

[0029] Structural features: The uniquely designed diaphragm microporous structure and the height difference between the diaphragm and the electrode (the middle of the diaphragm covers the electrode and the outer periphery of the diaphragm exceeds the outer periphery of the electrode) together constitute the physical basis for efficient bubble-free electrolysis.

[0030] Shape features: The three-dimensional mesh anode plate structure increases the surface area, optimizes the contact between the electrolyte and the electrode, and improves the catalytic efficiency.

[0031] Through the implementation of the above technical scheme, the present invention successfully solves the problem of low efficiency caused by bubble generation in traditional alkaline water electrolysis hydrogen production technology, which not only improves the overall electrolysis efficiency of the system, but also achieves the best balance between cost and performance, providing solid technical support for the development of the green hydrogen energy economy.

[0032] The electrolyzer of the present invention breaks through the performance limit of traditional alkaline electrolyzers, achieves unprecedented electrolysis efficiency, surpasses the conventional range of 42% to 78% of the industry standard, and jumps to a high efficiency range of more than 93%. The present invention effectively alleviates the efficiency limitations existing in the traditional electrolysis process, greatly reduces the cost burden of hydrogen production, and enhances the economic rationality and environmental sustainability of renewable energy applications.

[0033] Beneficial effects of the present invention:

[0034] The bubble-free interface optimized electrolytic cell system of the present invention shows significant advantages compared with the prior art, which are mainly reflected in the following aspects:

[0035] 1. Significantly improve electrolysis efficiency and hydrogen production: Experiments have shown that the electrolyzer system of the present invention has a 25% increase in hydrogen production compared to traditional electrolyzers while maintaining the same energy consumption. This improvement is attributed to the unique bubble-free transmission design and the application of high-efficiency catalytic electrodes, which reduce energy loss during the electrochemical reaction and improve hydrogen production efficiency.

[0036] 2. Improve gas purity and quality: The bubble-free electrolysis environment greatly reduces gas entrainment, making the separation of hydrogen and oxygen purer. Experimental data show that the purity of hydrogen reaches 99.9%, which is much higher than the industry standard (≥99.5%), and the purity of oxygen is also improved accordingly. This not only improves the quality of hydrogen as a clean energy, but also provides a better quality basic raw material for downstream applications.

[0037] 3. Enhance system stability and extend service life: The electrolytic cell structure design and the selection of corrosion-resistant materials of the present invention effectively avoid electrode corrosion and equipment damage caused by bubble accumulation. After simulation and actual operation tests, the electrolytic cell system of the present invention has a continuous working life of more than 5 years, which is 30% higher than the traditional system, reducing maintenance costs and replacement frequency.

[0038] 4. Energy saving and emission reduction, significant environmental benefits: Compared with traditional water electrolysis technology, the liquid level control and efficient mass transfer mechanism of the electrolyzer system of the present invention reduces energy consumption by about 15%. This means that in large-scale industrial production, electricity consumption can be saved by about 1 million degrees per year (based on an annual hydrogen production of 1,000 tons), greatly reducing carbon footprint and making a positive contribution to environmental protection.

[0039] The above beneficial effects are all based on rigorous theoretical analysis and practical experimental verification. The specific experimental methods follow the internationally recognized test standards to ensure the reliability and comparability of the data. Through structural innovation and process optimization, the present invention has not only achieved a breakthrough in technology, but also provided strong technical support for promoting the development of the green energy industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The overall structure of the electrolytic cell optimized for the bubble-free interface of the present invention is shown in FIG. Figure 1 .

[0041] Figure 2 The overall structure of the electrolytic cell optimized for the bubble-free interface of the present invention is shown in FIG. Figure 2 .

[0042] Figure 3 Optimizing the explosion of the electrolytic cell for the bubble-free interface of the present invention Figure 1 .

[0043] Figure 4 for Figure 3Enlarged view of point B in the middle.

[0044] Figure 5 Optimizing the explosion of the electrolytic cell for the bubble-free interface of the present invention Figure 2 .

[0045] Figure 6 Schematic diagram of the structure of the plate, electrode and diaphragm of the electrolytic cell for optimizing the bubble-free interface of the present invention Figure 1 .

[0046] Figure 7 Schematic diagram of the structure of the plate, electrode (covered by the diaphragm, not shown) and diaphragm of the bubble-free interface optimized electrolytic cell of the present invention Figure 2 .

[0047] Figure 8 This is a schematic structural diagram of the electrode plates of the bubble-free interface optimized electrolytic cell of the present invention.

[0048] Fig. 9 This is a schematic structural diagram of the anode plate of the bubble-free interface optimized electrolytic cell of the present invention.

[0049] Fig.10 This is a schematic structural diagram of the diaphragm of the bubble-free interface optimized electrolytic cell of the present invention.

[0050] Fig.11 This is a schematic structural diagram of the spacer of the bubble-free interface optimized electrolytic cell of the present invention.

[0051] Fig.12 This is a schematic structural diagram of the bubble-free interface optimized electrolytic cell system of the present invention.

[0052] The numbers in the accompanying drawings are: 1 for the end plate, 11 for the liquid inlet hole, 12 for the liquid outlet hole, 13 for the hydrogen hole, 14 for the oxygen hole, 15 for the bolt positioning hole, 2 for the electrode plate, 21 for the guide hole, 211 for the reinforcement plate, 22 for the step groove, 23 for the airway, 24 for the sealing groove, 3 for the anode plate, 4 for the diaphragm, 5 for the spacer, 51 for the electrode card hole, 6 for the cathode plate, 7 for the liquid replenishment tank, 71 for the pump, 72 for the regulating valve, 8 for the liquid replenishment pipeline, 9 for the circulation pipeline, 91 for the pipeline heater, 92 for the temperature detector, 93 for the concentration detector, and 10 for the bubble-free interface optimized electrolytic cell. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] Example 1: Evaluation of electrochemical performance of bubble-free interface optimized electrolyzer

[0055] 1. Bubble-free interface optimized electrolyzer

[0056] like Figure 1-11 As shown, the bubble-free interface optimized electrolyzer comprises:

[0057] The tank body comprises two end plates 1, and a pole plate 2 is arranged between the end plates 1, and there are at least two pole plates 2. The pole plate 2 and the upper part of one of the end plates 1 are both provided with oxygen holes 14 and hydrogen holes 13, and the oxygen holes 14 are connected to form an oxygen channel, and the hydrogen holes 13 are connected to form a hydrogen channel.

[0058] A diaphragm 4 is provided between the electrode plates 2, and an anode chamber and a cathode chamber are provided on both sides of the diaphragm 4 and between the electrode plates 2, respectively. The anode chamber is connected to the oxygen channel, and the cathode chamber is connected to the hydrogen channel; electrodes are provided in both the anode chamber and the cathode chamber, and specifically, an anode plate 3 is provided in the anode chamber, and a cathode plate 6 is provided in the cathode chamber. This arrangement allows the oxygen generated in the anode chamber to be separated through the oxygen channel, and the hydrogen generated in the cathode chamber to be separated through the hydrogen channel. The diaphragm 4 is fitted with the electrode, the middle part of the diaphragm 4 covers the electrode, and the periphery of the diaphragm 4 exceeds the periphery of the electrode. In addition, the portion of the diaphragm 4 that exceeds the periphery of the electrode extends into the liquid inlet channel and is provided with micropores (micropores are not shown in the figure), the pore size of the micropores is 1 to 5 μm, and the portion of the middle part of the diaphragm 4 that covers the electrode is not provided with holes. The portion of the diaphragm 4 that exceeds the periphery of the electrode is provided with micropores, so that the electrolyte absorbed by the periphery of the diaphragm 4 diffuses faster. The portion of the diaphragm that covers the electrode is not provided with holes, and is kept sealed to prevent gas exchange between the anode chamber and the cathode chamber. To facilitate cutting, the micropores on the diaphragm 4 are all set to 3 μm.

[0059] like Figure 3 , 5 -8, the electrode plate 2 is provided with a stepped groove 22 on one side or both sides, the electrode card is arranged on the first step near the bottom of the stepped groove 22, and a gas channel 23 connected to the oxygen hole or the hydrogen hole is provided on the wall of the stepped groove 22. An anode chamber or a cathode chamber is formed between the portion of the diaphragm 4 that fits the electrode and the stepped groove 22, and a gas storage chamber is formed between the electrode and the bottom of the stepped groove 22. The gas generated by the reaction between the electrode and the electrolyte is separated from the gas storage chamber, the gas channel 23, the oxygen hole 14 or the hydrogen hole 13 in sequence.

[0060] As an implementation manner, two pole plates 2 are provided, the inner sides of the two pole plates 2 are provided with stepped grooves 22 , and the outer sides of the two pole plates 2 are smooth structures, and are arranged in close contact with the end plate 1 .

[0061] As another embodiment, the number of the electrode plates 22 is greater than 2, the inner sides of the two electrode plates 2 close to the end plate 1 are provided with stepped grooves 22, and the outer sides are smooth structures, and one side or both sides of the middle electrode plate 2 are provided with stepped grooves 22. Figure 1 , 3 As shown in Figure 5, three pole plates 2 are provided, and two end plates 1 are located at the outermost sides of all pole plates 2. The inner sides of the two pole plates 2 close to the end plates 1 are provided with step grooves 22, and the outer sides are smooth structures. One side of the middle pole plate 2 is provided with a step groove 22, and a spacer 5 is also provided on one side of the cathode plate 6 to achieve the sealing of the groove body. The size and shape of the spacer 5 are consistent with those of the pole plate 2. The pole plate 2 is also provided with oxygen holes 14, hydrogen holes 13, and flow guide holes 21. The middle part of the spacer 5 is also provided with an electrode clamping hole 51 for clamping the cathode plate 6, as shown in Figure 5. Fig.11 As shown. Figure 3-8 As shown, a sealing groove 24 is provided circumferentially on the edge of one or both sides of the electrode plate. After the electrolytic cell is installed, the sealing groove 24 presses the spacer 5 (rubber material) into the groove to achieve sealing.

[0062] like Figure 3 As shown, both end plates 1 are provided with a liquid inlet 11 and a liquid outlet 12. The position of the liquid inlet 11 is higher than that of the liquid outlet 12, and the liquid outlet 12 is located at the lower part of the tank body. The electrode plate 2 is provided with a flow guide hole 21, and the flow guide hole 21 is arranged around the outer periphery of the stepped groove 22. The liquid inlet 11 corresponds to the upper end of the flow guide hole 21. The outer periphery of the diaphragm 4 extends into the flow guide hole 21 and a gap is left between the diaphragm 4 and the outer wall of the flow guide hole 21. The diaphragm 4 does not block the oxygen channel and the hydrogen channel. The liquid inlet 11 and the flow guide hole 21 form a liquid inlet channel, and the liquid outlet 12 and the flow guide hole 21 form a liquid outlet channel. The electrolyte enters the guide hole 21 through the liquid inlet 11. The periphery of the diaphragm 4 located in the guide hole 21 absorbs the electrolyte and then diffuses to the middle of the diaphragm 4 and reacts in contact with the electrode. In addition, due to the effect of gravity, most of the electrolyte will gather in the lower part of the tank body. The lower part of the diaphragm 4 absorbs the electrolyte and diffuses to the middle of the diaphragm 4 and reacts in contact with the electrode. The gap between the periphery of the diaphragm 4 and the outer wall of the guide hole 21 is to allow the electrolyte to enter the electrode chamber (such as the cathode chamber) away from the liquid inlet from the electrode chamber on the side close to the liquid inlet, thereby forming a liquid inlet channel, or to allow the electrolyte to enter the electrode chamber on the side close to the liquid outlet 12 from the electrode chamber on the side close to the liquid outlet 12, thereby forming a liquid outlet channel. Furthermore, the outer wall of the guide hole 21 is higher than the periphery of the stepped groove 22. Figure 4 , 6 As shown in Figure 7, this structure can not only stabilize the diaphragm 4, but also meet the sealing requirements of the tank body.

[0063] As an embodiment, the end plate 1 is hexagonal (to facilitate the transportation of the electrolytic cell and ensure its stability on the work platform), and bolt positioning holes 15 are arranged circumferentially on the end plate 1. Bolts are placed in the bolt positioning holes 15 of the end plate 1 to fix the two end plates 1. The electrode plate 2 is circular, and the guide hole 21 is a circular ring with a broken upper part, such as Figure 7 , 8 As shown, the oxygen hole 14 and the hydrogen hole 13 are located at the annular disconnection of the flow guide hole 21. In addition, in order to improve the strength of the electrode plate 2, a reinforcing plate 211 can also be provided in the flow guide hole 21. In order not to block the flow of the electrolyte, the height of the reinforcing plate 211 is not higher than the inner wall of the flow guide hole 21 (i.e., the outer periphery of the stepped groove 22).

[0064] As an embodiment, the anode plate 3 is a circular mesh structure, and the cathode plate 6 is a circular plate structure. Figure 3 , 5 , as shown in Figure 9.

[0065] 2. Preparation of Bubble-free Interface Optimized Electrolyzer

[0066] 1. Cathode plate preparation

[0067] Substrate material selection: Commercially available gas diffusion layer GDL for fuel cells is used as the cathode substrate to ensure good gas permeability and conductivity. Before preparing the cathode material, the substrate material is first immersed in anhydrous ethanol and cleaned in an ultrasonic cleaner for 30 minutes to remove surface impurities, and then thoroughly dried in a fume hood to ensure that the surface is clean and free of residue.

[0068] Coating material formula: A mixture of 80wt% graphene powder with a particle size of 5nm and 20wt% platinum nanoparticles with a particle size of ≤5nm is selected as the coating material. This formula enhances the catalytic activity and hydrophilicity of the electrode through the high conductivity of graphene and the excellent catalytic performance of platinum nanoparticles.

[0069] Dispersion medium: A mixed solvent of deionized water and anhydrous ethanol in a volume ratio of 1:1 is used as the dispersion medium to balance the viscosity and fluidity to facilitate subsequent coating operations.

[0070] Cathode plate preparation process:

[0071] The mixture of graphene powder and platinum nanoparticles was added to the above dispersion medium, and ultrasonic treatment was performed for 3 hours using an ultrasonic dispersion device to ensure that the particles were evenly dispersed to obtain a dispersion.

[0072] The dispersion is evenly coated on the clean and dry gas diffusion layer by scraping or ultrasonic spraying to form a thin and uniform coating. The coating thickness is controlled at 2 to 4 μm. This thickness range ensures the uniformity and stability of the coating, while optimizing the catalytic activity and hydrophilicity of the electrode, and improving the efficiency and stability of the electrochemical reaction.

[0073] After coating, the sample was naturally air-dried at room temperature, and then placed in a nitrogen protective atmosphere furnace preheated to 300°C and kept warm for 2 hours for heat treatment to enhance the structural stability and catalytic activity of the coating. Finally, the sample was naturally cooled to room temperature to complete the preparation of the electrode.

[0074] 2. Anode plate and diaphragm selection

[0075] Anode plate: A commercial NiFeOOH electrocatalyst is used and uniformly coated on a fine Ni mesh (coating thickness is 1.5 μm) by electrodeposition technology to form a high-efficiency anode electrode to ensure efficient oxygen evolution reaction. The Ni mesh is a commercially available 46-mesh product.

[0076] Diaphragm material: A commercial hydrophilic porous PES (polyethersulfone) diaphragm is used, and the hydrophilicity and corrosion resistance of the diaphragm are enhanced, and micropores are set on the diaphragm.

[0077] (1) Hydrophilicity enhancement treatment: Although the PES membrane itself has a certain degree of hydrophilicity, in order to further optimize the transmission efficiency of the electrolyte, the membrane is also subjected to hydrophilicity enhancement treatment. The specific method is: put the PES membrane into a plasma treatment device and use oxygen plasma to treat the membrane surface for 10 to 30 minutes at a power of 50 to 100 W. This can introduce hydrophilic functional groups and improve surface wettability.

[0078] (2) Corrosion resistance enhancement treatment: In order to meet the needs of long-term stable operation of the electrolytic cell, the PES diaphragm was treated with corrosion resistance enhancement to make it more stable and durable in the electrolytic environment.

[0079] The corrosion resistance enhancement treatment method is as follows:

[0080] Nano-SiO2 is prepared by hydrolysis of ethyl orthosilicate, then dispersed in ethanol and treated with triethoxysilane for amination. The treated amination nano-SiO2 particles are mixed with PVDF and ethyl cellulose (EC) in a solvent and coated on the surface of the PES diaphragm to form an inorganic-organic composite coating with excellent corrosion resistance. The specific operation is as follows:

[0081] ① Stir and hydrolyze a 10wt% aqueous solution of ethyl orthosilicate at room temperature for 24 hours to obtain nano-SiO2.

[0082] ② The prepared nano-SiO2 was dispersed in 95% ethanol at a concentration of 2wt%, and 3wt% triethoxysilane was added. The mixture was stirred and reacted for 6 hours to obtain amino-modified nano-SiO2 particles.

[0083] ③ Mix the amino-modified nano-SiO2 particles with PVDF and ethyl cellulose (EC) in a mass ratio of 1:2:1, disperse them in NMP solvent to form a coating solution with a concentration of 10wt%. Apply the coating solution on the surface of PES, and control the coating thickness to be 3-5μm.

[0084] Among them, the PES diaphragm is made of high molecular weight PES material, and the molecular weight is specifically 100,000 to 200,000.

[0085] (3) Seal the middle of the diaphragm and design the peripheral microporous structure: Although the base material of the diaphragm is a commercial PES diaphragm, we have set a microporous structure on the part of the diaphragm that exceeds the periphery of the electrode. On the one hand, it allows the electrolyte to penetrate slowly, thereby facilitating the uniform distribution of the electrolyte between the electrodes. On the other hand, it also improves the rapid diffusion of the electrolyte from the periphery of the diaphragm to the middle of the diaphragm, and forms an ultra-thin liquid film on the electrode surface, which also prevents the formation of bubbles. The micropore diameter is controlled between 1 and 5 μm, which can not only ensure high ion conductivity, but also effectively prevent gas cross-penetration, maintaining efficient gas separation and transmission inside the electrolyzer.

[0086] The middle sealing of the diaphragm means that there are no holes in the middle part of the diaphragm covering the electrode (which greatly reduces the electrolyte absorption efficiency), maintaining the original barrier properties of the diaphragm to ensure that the gas does not penetrate from one side of the diaphragm to the other side, thereby maintaining efficient gas separation and transmission inside the electrolytic cell.

[0087] 3. Electrolyzer assembly

[0088] Assemble the electrolytic cell according to the structure of "bubble-free interface optimized electrolytic cell".

[0089] 4. Establishment of electrolytic cell system and filling of electrolytic cell

[0090] like Fig.12 As shown, the two liquid inlets of the electrolytic cell are connected to the liquid replenishment tank through a liquid replenishment pipe, the liquid replenishment tank is filled with alkali solution and pure water (at least two independent chambers are arranged in the liquid replenishment tank, and the two liquids are located in different chambers in the liquid replenishment tank), liquid level sensors are arranged on both sides of the electrolytic cell (the detection part of the liquid level sensor is located in the electrolytic cell, and the instrument part is located outside the electrolytic cell, which is not visible in the figure), a pump and a regulating valve are arranged on the liquid replenishment pipe, and the two liquid outlets of the electrolytic cell are connected through a circulation pipe, and a pump, a pipe heater, a temperature detector and a concentration detector are arranged on the circulation pipe to construct a bubble-free interface optimized electrolytic cell system.

[0091] Theoretically, the electrolysis reaction consumes only water in the electrolyte. After the water is consumed, when the liquid level sensor in the electrolytic cell detects that the liquid level is lower than the set value, the regulating valve will open, and the pure water in the replenishment tank can be used to replenish the pure water in the electrolytic cell until the liquid level returns to the set value; conversely, when the liquid level is too high, the regulating valve will close or reduce the replenishment amount to maintain the liquid level stable. However, if the temperature is too high during the reaction, the electrolyte concentration may decrease and be lower than the set value. At this time, the alkali solution in the replenishment tank can be used to replenish the alkali solution in the electrolytic cell to increase the electrolyte concentration to the set value. The pump on the circulation pipeline does not force the circulation of the electrolyte inside the electrolytic cell reaction chamber, but only circulates the unreacted electrolyte. The pipeline heater on the circulation pipeline is to keep the electrolyte temperature in the electrolytic cell at the reaction temperature. The temperature detector and concentration detector are used to detect the temperature and concentration of the electrolyte in the electrolytic cell respectively.

[0092] When in use, the electrolytic cell system of the present invention adopts 28wt% KOH solution as the electrolyte, which is precisely formulated and injected into the electrolytic cell through the liquid inlet hole. The electrolyte flows along the guide holes until it reaches a predetermined liquid level, ensuring that the diaphragm and the top of the electrolytic cell remain sealed to prevent gas penetration. The bottom of the diaphragm is in contact with the electrolyte, and the electrode is positioned higher than the electrolyte surface to promote spontaneous transmission of the electrolyte on the electrode surface through surface tension, forming a bubble-free and efficient electrolysis environment. During the flow of the electrolyte, the periphery of the diaphragm will also absorb the electrolyte from the guide holes and diffuse it toward the middle of the diaphragm. 5. Electrochemical test

[0093] The electrolyzer system was connected to an electrochemical workstation for cyclic voltammetry (CV) testing. The scan rate was set to 5 mV / s and the voltage range was from -1.2 V to +0.2 V. This setting was designed to evaluate the electrocatalytic performance of the electrolyzer system under bubble-free conditions in detail, especially the hydrogen production at the cathode and the oxygen release characteristics at the anode.

[0094] Data recording and analysis:

[0095] Start the electrochemical workstation to start the experiment, record the cyclic voltammetry curve in detail, and repeat each experiment at least three times to ensure the stability and reliability of the data. Pay special attention to the comparative analysis of the changes in electrode performance under the bubble-free transport mechanism and the traditional electrolytic cell, and evaluate the effect of the bubble-free environment on the improvement of electrochemical reaction efficiency.

[0096] System maintenance and preparation:

[0097] After each test, the electrodes were cleaned with pure 28 wt% KOH electrolyte to remove possible residues and ensure that the electrolytic cell was in a clean state and ready for the next experiment.

[0098] Experimental parameters:

[0099] Working electrode area: 100cm2 ;

[0100] Scan rate: 5mV / s;

[0101] Electrolyte: 28wt% KOH;

[0102] Voltage sweep range: -1.2V to +0.2V.

[0103] Experimental results:

[0104] The bubble-free interface optimized electrolyzer system of the present invention exhibits excellent performance. The cyclic voltammetry (CV) test results show that the electrolyzer system of the present invention achieves significant electrochemical activity enhancement under the action of the bubble-free transport mechanism. The CV curve on the cathode side clearly shows high-intensity hydrogen release, indicating efficient electrocatalytic activity; the anode side presents a smooth oxygen evolution process, proving the stability of the system and efficient gas separation capabilities. These characteristics are reflected in the low overpotential and sharp redox peaks in the curve. Compared with traditional electrolyzers, the electrolyzer system of the present invention exhibits smaller charge transfer resistance and higher reaction kinetics. The performance comparison of the electrolyzer system of the present invention and the traditional electrolyzer is shown in Tables 1-5. The traditional electrolyzer adopts the existing technology, which is a standard square electrolyzer of Huadian Caofeidian Heavy Industry Equipment Co., Ltd.

[0105] At a scan rate of 5 mV / s, an ultra-thin liquid film is formed between the diaphragm and the electrode of the electrolytic cell of the present invention. The stable maintenance of the ultra-thin liquid film and the efficient catalytic effect of the three-dimensional mesh electrode enable the system to exhibit a continuous and stable current response, further verifying the decisive role of the bubble-free electrolysis environment in improving the electrolysis efficiency. Experimental data show that even under long-term continuous operation (1000 hours) and high current density (200 mA / cm 2 ), the electrolysis efficiency of the electrolytic cell system of the present invention is still stably maintained at more than 93%, far exceeding the efficiency range of traditional electrolytic cells. The reason for the formation of ultra-thin liquid film: the diaphragm is very hydrophilic, and the electrode is also hydrophilic due to the catalyst. The distance between the two is very close, and the liquid film is formed between the two through the surface tension of water and the hydrophilicity between the two.

[0106] In addition, the gas purity analysis results show that the purity of hydrogen produced by the electrolyzer system of the present invention reaches 99.9%, and the purity of oxygen is also significantly improved, both of which are better than the industry standard, which directly reflects the success of the bubble-free interface optimized electrolyzer system of the present invention in reducing gas cross contamination and improving product quality. These results not only prove the remarkable effectiveness of the system in improving hydrogen production efficiency, but also emphasize its excellent performance in ensuring gas quality, laying a solid foundation for the high-end application of hydrogen energy.

[0107] In summary, the above experimental results fully verify the technological advancement of the bubble-free interface optimized electrolyzer system, which not only achieved innovative breakthroughs in theoretical design, but also demonstrated significant performance advantages in practical applications.

[0108] Table 1: Cyclic voltammetry (CV) test results

[0109] Test Parameters Traditional electrolyzer Bubble-free interface optimized electrolyzer system Scan rate (mV / s) 5 5 Voltage range(V) -1.2 to +0.2 -1.2 to +0.2 Electrolyte concentration (wt%) 28 28 <![CDATA[Working electrode area (cm 2 )]]> 100 100 Overpotential(mV) 400 300 Charge transfer resistance (Ω) 15 8 <![CDATA[Hydrogen evolution current ( mA / cm 2 )]]> 150 200 <![CDATA[Oxygen evolution current ( mA / cm 2 )]]> 120 150 <![CDATA[Electrochemical active area (cm 2 )]]> 20 25 Hydrogen evolution overpotential (mV) 450 350 Oxygen evolution overpotential (mV) 480 380 Electrolysis efficiency (%) 78 93 Stability test (hours) 500 1000 Efficiency after stability test (%) 75 93

[0110] Table 2: Cathode side cyclic voltammetry (CV) curve data

[0111]

[0112]

[0113] Table 3: Cyclic voltammetry (CV) curve data of anode side

[0114] Potential (V) <![CDATA[Traditional electrolytic cell current ( mA / cm 2 )]]> <![CDATA[Bubble-free interface optimized electrolytic cell system current ( mA / cm 2 )]]> -1.2 0 0 -1.1 0 0 -1.0 0 0 -0.9 0 0 -0.8 0 0 -0.7 0 0 -0.6 0 0 -0.5 0 0 -0.4 0 0 -0.3 0 0 -0.2 0 0 -0.1 0 0 0.0 0 0 0.1 0 0 0.2 0 0 0.3 10 15 0.4 20 30 0.5 30 45 0.6 40 60 0.7 50 75 0.8 60 90 0.9 70 105 1.0 80 120 1.1 90 135 1.2 100 150

[0115] Table 4: Long-term continuous operation performance

[0116] Running time (hours) Electrolysis efficiency of traditional electrolytic cell (%) Electrolysis efficiency of the electrolytic cell system optimized by bubble-free interface (%) 100 85 95 500 80 93 1000 75 93

[0117] Table 5: Gas purity analysis results

[0118] Gas Type Purity of traditional electrolytic cell (%) Bubble-free interface optimized electrolytic cell system purity (%) hydrogen 99.0 99.9 oxygen 98.5 99.5

[0119] 6. Hydrogen production test

[0120] Experimental conditions: current density is 200mA / cm 2 , the electrolyte concentration was 30wt% KOH, the temperature was maintained at 80℃, and it operated continuously for 1000 hours.

[0121] Under the above experimental conditions, the hydrogen production of the electrolyzer system of the present invention and the conventional electrolyzer were tested. The results showed that the hydrogen production of the electrolyzer system of the present invention was increased by 25% compared with the conventional electrolyzer under the same energy consumption conditions.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bubble-free interface optimized electrolytic cell, comprising: a cell body, on which a hydrogen channel, an oxygen channel, a liquid inlet channel and a liquid outlet channel are arranged, wherein the hydrogen channel and the oxygen channel are located at the upper part of the cell body, characterized in that: A diaphragm is arranged in the tank body, and an anode chamber and a cathode chamber are respectively arranged on both sides of the diaphragm and between the tank body, the anode chamber is connected to the oxygen channel, and the cathode chamber is connected to the hydrogen channel; an anode plate and a cathode plate are respectively arranged in the anode chamber and the cathode chamber; the diaphragm is fitted with the electrode, the middle part of the diaphragm covers the electrode and the outer periphery of the diaphragm exceeds the outer periphery of the electrode; the part of the diaphragm that exceeds the outer periphery of the electrode extends into the liquid inlet channel and is provided with micropores, and the pore size of the micropores is 1 to 5 μm.

2. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: The trough body includes end plates, and pole plates are arranged between the end plates, and there are at least two pole plates; oxygen holes and hydrogen holes are arranged on the upper parts of the pole plates and one of the end plates, and the oxygen holes are connected to form an oxygen channel, and the hydrogen holes are connected to form a hydrogen channel.

3. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: A stepped groove is provided on one side or both sides of the electrode plate, the electrode card is arranged on the first step close to the bottom of the stepped groove, and an airway connected to the oxygen hole or the hydrogen hole is provided on the wall of the stepped groove.

4. The bubble-free interface optimized electrolytic cell according to claim 3, characterized in that: The end plate is provided with a liquid inlet and a liquid outlet, the electrode plate is provided with a guide hole, the guide hole is arranged around the outer periphery of the step groove, and the liquid inlet corresponds to the upper end of the guide hole; the outer periphery of the diaphragm extends into the guide hole and a gap is left between the outer wall of the guide hole, and the diaphragm does not block the oxygen channel and the hydrogen channel.

5. The bubble-free interface optimized electrolytic cell according to claim 4, characterized in that: The guide hole is in a ring-shaped structure with a disconnected upper portion, and the oxygen hole and the hydrogen hole are located at the disconnected portion of the guide hole.

6. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: A spacer is arranged on one side of the electrode. The size and shape of the spacer are consistent with those of the electrode plate. The spacer is provided with oxygen holes, hydrogen holes and flow guide holes. An electrode clamping hole for clamping the electrode is also opened in the middle of the spacer.

7. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: The cathode plate uses a gas diffusion layer as a cathode substrate, and after cleaning and drying, a coating material is coated. The coating material is prepared by dispersing a mixture of 80 wt% graphene powder and 20 wt% platinum nanoparticles with a particle size of ≤5 nm in a dispersion medium. The dispersion medium is prepared by a mixed solvent of deionized water and anhydrous ethanol in a volume ratio of 1:

1.

8. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: The anode plate is in a mesh structure. The preparation method of the anode plate is as follows: NiFeOOH electrocatalyst is evenly coated on a Ni mesh by an electrodeposition technology.

9. The bubble-free interface optimized electrolytic cell according to claim 1, characterized in that: The preparation method of the diaphragm comprises: using oxygen plasma to perform hydrophilic enhancement treatment on the surface of the polyethersulfone diaphragm, and performing corrosion resistance enhancement treatment on the polyethersulfone diaphragm; The corrosion resistance enhancement treatment is as follows: preparing nano-SiO2 by hydrolyzing ethyl orthosilicate, dispersing it in ethanol, adding triethoxysilane for amination treatment, mixing the treated amination nano-SiO2 particles with PVDF and ethyl cellulose in a solvent, and coating the mixture on the surface of the polyethersulfone diaphragm.

10. Bubble-free interface optimized electrolytic cell system, characterized in that: An electrolytic cell comprising the electrolytic cell according to any one of claims 1 to 9, wherein both end plates of the electrolytic cell are provided with a liquid inlet hole and a liquid outlet hole, the two liquid inlets of the electrolytic cell are connected to a liquid replenishment tank through a liquid replenishment pipe, the liquid replenishment tank is filled with alkali solution and pure water, liquid level sensors are provided on both sides of the electrolytic cell, and a pump and a regulating valve are provided on the liquid replenishment pipe; The two liquid outlets of the electrolytic cell are connected through a circulation pipeline, and a pump, a pipeline heater, a temperature detector and a concentration detector are arranged on the circulation pipeline.

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