Improved interdigital jet flow field device and proton exchange membrane water electrolysis hydrogen production device thereof

Abstract

The invention discloses an improved interdigital jet flow field device and a proton exchange membrane water electrolysis hydrogen production device thereof, and aims to solve the problems of non-uniform reactant distribution, gas retention, local hot spots and the like of a traditional flow field. The traditional flow field design, such as a parallel flow channel and a snakelike flow channel, generally has certain limitations in the aspects of fluid flow resistance, mass transfer efficiency, thermal management uniformity and the like, and is difficult to meet the requirements of a high-performance water electrolysis device; through an optimized geometric structure and a gas emission strategy, uniform distribution of reactants is promoted, and gas stagnation areas and local high hot spots are reduced, so that more efficient current density distribution uniformity and heat production management uniformity are realized. The flow field adopts a staggered jet flow channel structure, and is combined with an optimally designed under-rib opening channel, so that the vertical flow velocity is increased, the pressure drop is reduced, and the gas-liquid interface reaction efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of electrochemical device and flow field design, and relates to a device, in particular to an improved interdigital jet flow field device and a proton exchange membrane water electrolysis hydrogen production device. Background Art

[0002] With the rapid development of social economy and the large-scale use of fossil energy, environmental and energy issues have become an important obstacle to the sustainable development of society. In the face of this challenge, it has become a top priority to explore new forms of energy to reduce environmental pollution and reduce dependence on fossil energy. Among the many new energy forms, hydrogen energy stands out for its high efficiency and environmental protection characteristics and is regarded as an important driver of green energy transformation. Hydrogen energy is a secondary energy produced by electrolyzing water using renewable energy. This process not only produces hydrogen in an environmentally friendly way, but also has the advantages of high efficiency and cleanliness. By using renewable energy such as wind power and solar energy to electrolyze water to produce hydrogen, it can not only provide green hydrogen energy for transportation, chemical industry, etc., and help deep decarbonization, but also use excess and off-peak electricity to produce hydrogen, significantly reducing the production cost of hydrogen energy.

[0003] Proton exchange membrane water electrolysis (PEMWE) technology has great potential as an efficient hydrogen production technology. By implementing the electrolysis process through a proton exchange membrane, PEMWE technology has higher efficiency and lower energy consumption than traditional alkaline water electrolysis technology. This is mainly attributed to the fact that the proton exchange membrane can effectively prevent the mixing of oxygen and hydrogen, achieve rapid proton transfer, and improve the rate and efficiency of the electrolysis reaction. At the same time, PEMWE technology has a higher current density and can produce more hydrogen per unit area, reducing production costs and improving production efficiency. In addition, PEMWE technology can also produce high-purity hydrogen, which is of great significance for applications such as fuel cells and can improve the stability and performance of the equipment. In addition, PEMWE technology has high flexibility and can adjust the hydrogen production according to demand to adapt to different energy needs and production scales. It is widely used in energy storage, industrial manufacturing, aerospace and other fields. Finally, PEMWE technology has also improved in terms of safety. The proton exchange membrane can effectively prevent the mixing of hydrogen and oxygen, reduce the risk of explosion, and the operating temperature is low, which reduces safety hazards. Therefore, PEMWE technology, with its improved performance, high current density, high-purity hydrogen, flexibility and safety characteristics, provides strong technical support for sustainable hydrogen production and is expected to play an important role in promoting the development of the hydrogen energy industry and facilitating the clean energy transition.

[0004] The flow field is one of the key components of proton exchange membrane cells, playing an important role in supporting the membrane electrode assembly and distributing reactants (Kang, Yang, Mo, Li, Yu, Cullen, Retterer, Toops, Bender, Pivovar, Green, & Zhang, 2018. Novel thin / tunable gas diffusion electrodes with ultra-low catalyst loading for hydrogen evolution reactions in proton exchange membrane electrode cells. In Nano Energy, Vol. 47, 434-441; Mo, Kang, Retterer, Cullen, Toops, Green, Mench, & Zhang, 2016. Discovery of true electrochemical reactions for ultrahigh catalyst mass activity in water splitting. In Science Advances, Vol. 2). Its structural parameters, such as flow field pattern, channel width, depth and rib width, directly affect the uniform distribution of reactants and the performance of the electrolyzer (Zhang & Xing, 2020. Simulation and experiment of heat and mass transfer in a proton exchange membrane electrolysis cell. In International Journal of Hydrogen Energy, Vol. 45, 20184-20193). A reasonably designed flow field pattern can effectively reduce the local concentration difference of reactants in the membrane electrode assembly and improve the uniformity and stability of the electrolysis reaction. The width and depth of the channel determine the flow velocity and flow rate of the reactants, and the flow state in the channel also affects the transmission efficiency of the reactants. The design of the ribs affects the flow distribution in the channel, which in turn affects the transmission and distribution uniformity of the reactants.By optimizing the structural design of the flow field, the efficiency and stability of the proton exchange membrane electrolyzer can be further improved, and its wide application in the field of energy conversion and storage can be promoted. The reasonable design of the flow field structure is one of the keys to achieve efficient and stable electrolysis reactions (Lin, Lu, Xu, Huo, & Cai, 2022. Investigation on performance of proton exchange membrane electrolyzer with different flow field structures. In Applied Energy, Vol. 326, 120011). Li et al. (Li & Sabir, 2005. Review of bipolar plates in PEM fuel cells: Flow-field designs. In International Journal of Hydrogen Energy, Vol. 30, 359-371) summarized the advantages and disadvantages and applications of common flow fields (needle-shaped, parallel, serpentine, forked, etc.), and gave a schematic diagram of each flow field. The parallel flow field in the flow field is the most common flow field, which consists of multiple parallel channels of the same length and two manifolds connecting each parallel channel. Maharudrayya et al. (Maharudrayya, Jayanti, & Deshpande, 2006. Pressure drop and flow distribution in multiple parallel-channel configurations used in proton-exchange membrane fuel cell stacks. In Journal of Power Sources, Vol. 157, 358-367) studied the parallel flow fields of different structures and expanded the simple U / Z type structure. The results showed that for certain types of multi-parallel structures, better flow distribution can be obtained with a relatively small increase in pressure drop.Toghyani et al. (Toghyani, Afshari, Baniasadi, & Atyabi, 2018. Thermal and electrochemical analysis of different flow field patterns in a PEM electrolyzer. In Electrochimica Acta, Vol. 267, 234-245) based on finite volume method modeling, analyzed and compared five flow field modes: parallel, single-path serpentine, double-path serpentine, three-path serpentine and four-path serpentine. The results showed that the double-path serpentine had the best performance. Agarwal et al. (Agarwal, Thosar, Bhat, & Lele, 2022. Interdigitated flow field impact on mass transport and electrochemical reaction in high-temperature polymer electrolyte fuel cell. In Journal of Power Sources, Vol. 532, 231319) simulated the interdigitated flow field and compared it with the parallel flow field. The results showed that the interdigitated flow field had better performance, and the interdigitated flow field had an optimal value of the channel-to-rib ratio and an optimal value of current density saturation.

[0005] Pedapati et al. (Pedapati, Dhanushkodi, Chidambaram, Taler, Sobota, & Taler, 2024. Design and Manufacturing Challenges in PEMFC Flow Fields—A Review. In Energies, Vol. 17) summarized and discussed the effects of various flow fields (common flow fields and their derived optimized flow fields) and the geometric characteristics of flow fields on performance and various distributions, and proposed that each flow field has its own unique features, but flow field design should focus on performance, current distribution, reactant distribution, and pressure drop size. Therefore, in addition to common flow fields, many new structures have been proposed to improve battery performance and distribution uniformity. Atyabi et al. (Atyabi & Afshari, 2019. Three-dimensional multiphase model of proton exchange membrane fuel cell with honeycomb flowfield at the cathode side. In Journal of Cleaner Production, Vol. 214, 738-748) proposed a new type of honeycomb flow field on the cathode side by combining the multi-channel serpentine flow field and the linear parallel flow field. It has the advantages of uniform parameter distribution of the multi-channel serpentine flow field and low pressure drop of the linear parallel flow field, effectively avoiding flooding and hot spot generation. Olesen et al. (Olesen, & 2016.Anumerical study of the gas-liquid,two-phase flow maldistribution in the anode of a high pressure PEM waterelectrolysis cell.In International Journal of Hydrogen Energy,Vol.41,52-68) established a circular high-pressure forked-finger PEMFC model, taking into account turbulence, heat transfer and related dispersion phenomena, and explained that if ribs and flow channels of equal width are used, the circular staggered flow field will be unevenly distributed. In addition, Olesen et al. (Olesen, Frensch, & Kaer, 2019. Towards uniformly distributed heat, mass and charge: A flow field design study for high pressure and high current density operation of PEMelectrolysis cells.In Electrochimica Acta,Vol.293,476-495) developed a three-dimensional PEMEC model that can accurately simulate full-size batteries at a current density of 5A / cm-2, and used this model to evaluate circular high-voltage forked-finger batteries at high current density. Lafmejani et al (Lafmejani, Müller, Olesen, & 2018. Experimental and numerical study of flow in expanded metal plate for water electrolysis applications. In Journal of Power Sources, Vol. 397, 334-342) Expanded metal was applied to the flow field plate, and a transparent experimental device was used to visualize the flow distribution of gas and liquid in the expanded metal plate, and the flow resistance characteristics of two different sizes of expanded metal in the horizontal and vertical directions were determined. Khatib et al. (Khatib, Wilberforce, Thompson, & Olabi, 2021. Experimental and analytical study of open pore cellular foam material on the performance of proton exchange membrane electrolysers. In International Journal of Thermofluids, Vol. 9, 100068) proposed an open-pore foam flow channel (OPCF) by combining serpentine flow field and mesh flow field. The results showed that the performance of OPCF battery was significantly improved. Deng et al. (Deng & Li, 2022. Aporous-rib flow field for performance enhancement in proton exchange membrane fuel cells. In Energy Conversion and Management, Vol. 263, 115707) proposed a porous rib flow field to improve gas transport and drainage under the ribs. The results showed that the battery limit current density and peak power density based on the porous rib structure increased by 15% and 9%, respectively, and the pressure drop was reduced by 38%. Wu et al. (Wu, An, Jiao, Xu, Zhang, & Jiao, 2022. Enhanced oxygen discharge with structured mesh channel in proton exchange membrane electrolysis cell. In Applied Energy, Vol. 323, 119651) proposed a structured mesh channel design to improve oxygen discharge capacity. The channel contains a row of repeated solid skeleton structures. The results show that the hydrophobicity (i.e., contact angle) of the skeleton surface is gradually reduced from the top of the channel to the GDL surface, which helps to improve the oxygen release capacity.Kang et al. (Kang, Yu, Yang, Li, Bender, Pivovar, Green, & Zhang, 2019. Performance improvement of proton exchange membrane electrolyzer cells by introducing in-plane transport enhancement layers. In Electrochimica Acta, Vol. 316, 43-51) proposed an in-plane transport enhancement layer to form a double-layer diffusion layer structure to improve mass diffusion. The results show that the double-layer structure has a smaller ohmic resistance and mass transfer resistance. Toghyani et al. (Toghyani, Afshari, & Baniasadi, 2018. Metal foams as flow distributors in comparison with serpentine and parallel flow fields in proton exchange membrane electrolyzer cells. In Electrochimica Acta, Vol. 290, 506-519) proposed using metal foam as a flow distributor, which has a lower temperature gradient and a more uniform distribution of hydrogen mass fraction.

[0006] In order to better study the influence of flow field on distribution uniformity, numerical simulation methods have been widely used. Majumdar et al. (Majumdar, Haas, Elliot, & Nazari, 2023. Control and control-oriented modeling of PEM water electrolyzers: A review. In International Journal of Hydrogen Energy, Vol. 48, 30621-30641) summarized PEM water electrolyzer models related to control development. Ma et al. (Ma, Witteman, Wrubel, & Bender, 2021. A comprehensive modeling method for proton exchange membrane electrolyzer development. In International Journal of Hydrogen Energy, Vol. 46, 17627-17643) proposed a modeling method that focuses on the scale of cells and stacks to comprehensively simulate the performance and distribution of electrolyzers. Maier et al. (Maier, Smith, Dodwell, Hinds, Shearing, & Brett, 2022. Mass transport in PEM water electrolysers: A review. In International Journal of Hydrogen Energy, Vol. 47, 30-56) summarized the different flow states in mass transport in PEMEC modeling, the flow field geometry, and the calculation of related mass flows during the modeling process. In order to determine the influence of flow field structure parameters on battery distribution, Manso et al. (Manso, Marzo, Barranco, Garikano, & Garmendia Mujika, 2012. Influence of geometric parameters of the flow fields on the performance of a PEM fuel cell. A review. In International Journal of Hydrogen Energy, Vol. 37, 15256-15287) summarized the performance and distribution of a series of common flow fields and new flow fields after comparative modeling, and concluded that effective design of flow fields can solve problems such as mass transport of reactants, water management and poor distribution.Zhang et al. (Zhang, Huang, Zhou, & Xu, 2024. Enhancing oxygen transport performance with improved serpentine flow field on the anode side of the PEMEC. In International Journal of Hydrogen Energy, Vol. 82, 881-891) tracked the moving interface of the two phases in the PEMEC anode flow field based on the VOF method. By adopting this method, the movement characteristics of the gas and liquid phases in the flow field can be more accurately understood and analyzed, and ultimately the performance of the model can be optimized and improved.

[0007] Wei et al. (Wei, Fan, & Tu, 2023. Hydrogen production in a proton exchange membrane electrolysis cell (PEMEC) with titanium meshes as flow distributors. In International Journal of Hydrogen Energy, Vol. 48, 36271-36285) proposed using Ti mesh as a flow distributor to replace the flow channel. During modeling, species transfer was simulated by the dilute species transport module. Zhang et al.

[30] established a single-channel electrolyzer consisting of half ribs and half channels, and used it as a model to expand it to the basic unit of the entire flow field and PEM electrolysis cell to study the difference in local voltage distribution between ribs and flow channels.

[0008] Compared with experiments, a major advantage of numerical simulation is that it can ensure safety, especially when high pressure is involved. Haas et al. (Haas, Macherhammer, Klopcic, & Trattner, 2021. Capabilities and Limitations of 3D-CFD Simulation of Anode Flow Fields of High-Pressure PEM Water Electrolysis. In Processes, Vol. 9) established a two-phase three-dimensional model to simulate and analyze the two-phase flow of the anode porous transport layer under high pressure in the PEM electrolyzer. In addition, numerical simulation can explore and study the two-phase flow that cannot be observed macroscopically. Lafmejani et al. (Lafmejani, Olesen, & 2017.VOF modelling of gas–liquid flow inPEM water electrolysis cell micro-channels.In International Journal of Hydrogen Energy,Vol.42,16333-16344) used a three-dimensional transient computational fluid dynamics (CFD) model to analyze the gas fluid flow through the anode interdigital flow field of the PEM water electrolysis cell (PEMEC). The results showed that the distance between Taylor bubbles has a great influence on the uniformity of the liquid flow in the incident channel. Chen et al. (Chen, Wang, Yang, & Xu, 2020. Two-dimensional multi-physics modeling of porous transport layer inpolymer electrolyte membrane electrolyzer for water splitting. In International Journal of Hydrogen Energy,Vol.45,32984-32994) established a two-dimensional multi-physics model to study the effect of diffusion layer thickness on liquid water saturation and local current density. The results showed that the thickness of the diffusion layer will significantly affect the diffusion and distribution of liquid water to the catalytic layer.

[0009] In summary, most of the research on flow field focuses on the impact of two-phase flow on battery performance and uniformity distribution, and ribs, as an important component of the flow field, have a great impact on mass transfer and heat transfer. At present, traditional flow field designs such as parallel flow channels, serpentine flow channels and interdigital flow channels are usually difficult to achieve efficient reactant distribution and product discharge, and are prone to local retention areas, hot spots and energy loss problems, thereby limiting the further improvement of the performance of water electrolysis devices.

[0010] Regarding the structural design of the entire electrolytic cell and flow field, Chinese patent CN117973048A discloses a combined flow field of an electrolytic cell, which aims to improve the reaction rate of the battery. However, the patent only proposes a new flow field from the perspective of simulation, and has not been verified in actual application, and does not consider the feasibility of flow field design under high pressure and high power density. The lack of experimental verification makes it impossible to effectively guarantee the stability, efficiency and actual operating performance of the flow field, so its practical application value is limited. Chinese patent CN116632423A proposes a 3D-printed battery structure that achieves higher energy storage efficiency by reducing the internal resistance of the battery. However, the substrate manufacturing process of this structure is complicated and has high requirements for materials, which increases the production cost, and the design fails to consider the improvement of flow field uniformity and reaction efficiency. In addition, although the 3D printing process has advantages in structural optimization, its stability and reliability still need to be further verified compared with traditional manufacturing processes, and it is not conducive to large-scale industrial production. Chinese patent CN105244517A proposes a flow field design for a proton exchange membrane battery bipolar plate, which can effectively improve battery performance, but the air intake channel in its design is relatively complex and fails to further optimize the uniformity of the flow field. The complex air intake channel design not only increases the manufacturing difficulty, but also may cause uneven airflow in local areas of the flow field, affecting the overall performance of the battery. The design does not conduct in-depth research on the uniformity of the flow field, which may lead to uneven distribution of reactants, thereby affecting the electrolysis efficiency. Chinese patent CN108987763A proposes a structure with a graded interdigitated flow field, which effectively reduces pump power loss. However, the design has too many interdigitated flow channels, resulting in a complex structure and greater processing difficulty, which increases production costs and may cause unnecessary flow resistance in the flow field, further affecting the reaction efficiency. In addition, too many interdigitated flow channels may increase the volume and weight of the battery assembly, which may be detrimental to space utilization and overall performance optimization in practical applications. Summary of the invention

[0011] The present invention relates to an improved flow field design applied to a proton exchange membrane water electrolysis hydrogen production device, which aims to solve the technical problems of uneven distribution of reactants, gas retention, local hot spots and uneven current density distribution in traditional flow field design, thereby improving the mass transfer efficiency, thermal management performance and overall electrochemical performance of the device. The specific technical solutions proposed by the present invention are as follows:

[0012] An improved interdigital jet flow field device, characterized in that it comprises:

[0013] Double plate setting: including interdigital plate and jet plate, the two plates cooperate to achieve efficient forced convection effect, thus significantly improving the uniformity of reactant distribution and mass transfer efficiency in the flow field;

[0014] Finger plate: The finger plate guides the fluid flow through a staggered fin structure with a fin width of 1mm, a spacing of 1mm, and a thickness of 1mm. The selection of this fin structure not only effectively increases the contact area between the fluid and the solid surface, but also forms a mainstream path for forced convection, thereby enhancing the mixing and mass transfer performance of the fluid. Specifically, the fin width is set to 1mm, which can promote fluid disturbance and flow uniformity without significantly increasing the flow resistance. If the width is too large, the cross-sectional area of ​​the flow channel will decrease, the flow resistance will increase, and the stability of the flow field will be affected; while a width that is too small may not be able to effectively break the airflow layer, resulting in local gas accumulation and affecting the uniformity of the reaction. Therefore, the selection of 1mm wide fins not only optimizes the airflow distribution, but also avoids unnecessary pressure loss.

[0015] Jet plate: The jet plate is designed with a direct current channel structure, the jet aperture is set to 0.3-0.4mm, the depth is 0.1mm, and the center spacing between the jet holes is 1.5mm. The choice of jet aperture can achieve a good balance between flow resistance and reaction efficiency. If the jet aperture is too large, it will reduce the pressure difference and affect the effect of forced convection; while if the aperture is too small, the fluid cannot be fully disturbed, affecting the uniform distribution and mass transfer efficiency of the gas. The aperture of 0.3-0.4mm effectively ensures the full mixing of the airflow and ensures the formation of a moderate injection effect in the flow channel, thereby improving the reaction efficiency. The depth of the jet hole is 0.1mm, which is designed to ensure that the fluid can effectively enter the flow channel and fully mix with the reaction gas, which can not only promote the disturbance of the gas, but also reduce the pressure loss of the flow.

[0016] The double-plate combination design not only introduces a forced convection mechanism, but also optimizes the fluid dynamics performance, making the fluid flow more uniform, significantly reducing the local retention area and reaction dead zone, and improving the overall reaction efficiency;

[0017] A number of small openings are evenly arranged in the sub-rib area to improve the cross-channel flow of the fluid and the discharge of the reactants. The opening diameter is 0.2 mm and the spacing is 1.5 mm, which can effectively reduce the resistance in the gas-liquid separation process and increase the degree of fluid mixing in the flow field. The opening positions are optimized to avoid the formation of local gas retention areas, improve the exhaust efficiency, and further promote the uniform distribution of the reactants. An opening diameter that is too large may cause the pressure difference to decrease and affect the flow rate; while a diameter that is too small may limit the flow of the fluid and fail to achieve a uniform distribution effect. Therefore, the selection of an aperture of 0.2 mm and a hole spacing of 1.5 mm can ensure sufficient airflow without increasing excessive flow resistance, effectively improving the uniformity of the fluid and the discharge effect of the reactants. The linkage design of the sub-rib opening and the jet channel allows the reactants and products to circulate inside and outside the channel, thereby improving the overall reaction efficiency and mass transfer performance of the electrolyzer.

[0018] Preferably, the interdigital plate and the jet plate are arranged in an adjacent mode, and the jet plate is closely attached to the MEA, so as to further optimize the fluid path and the jet effect and ensure the stable flow of the fluid.

[0019] Preferably, the ratio of the fin length of the interdigital plate to the channel length of the jet plate is 10: 1. Experimental verification shows that this ratio effectively improves the stability and mass transfer efficiency of the fluid, ensuring good flow and reaction performance.

[0020] Preferably, the ratio of the fin length of the interdigital plate to the channel length of the jet plate is 10:1, which improves mass transfer without affecting heat dissipation and conductivity, enhances the synergy between the two plates, and further improves the reaction efficiency.

[0021] Preferably, the finger plates and the jet plates are made of metal or composite materials with high corrosion resistance and good thermal conductivity, and are suitable for operation in high temperature and high pressure environments.

[0022] Preferably, the fin structure of the interdigital plate and the opening position of the jet plate are optimized by CFD simulation to ensure efficient fluid distribution and product discharge.

[0023] Preferably, the opening is circular in design and is separated from the jet plate channel to form a flow mechanism in an independent space, thereby further improving the distribution uniformity of the reactants and the mass transfer performance.

[0024] Preferably, the double-plate structure can be replaced modularly, and the size and opening layout of the fork plate and the jet plate can be adjusted according to actual working conditions to adapt to various application scenarios.

[0025] The invention also discloses a proton exchange membrane water electrolysis hydrogen production device, which is characterized by comprising the above-mentioned improved interdigital jet flow field device.

[0026] Beneficial Effects

[0027] (1) Improving the uniformity of reactant distribution: Through the staggered arrangement of the jet channel structure, the present invention significantly improves the uniform distribution of the fluid in the flow field, effectively reduces the phenomenon of local reactant shortage and gas retention, and improves the reaction efficiency of the water electrolysis device.

[0028] (2) Reducing flow resistance and pressure drop: The present invention optimizes the geometric design of the flow field. The width, spacing and length of the jet channel are reasonably configured. While ensuring the uniformity of fluid distribution, the flow resistance and overall pressure drop are reduced, thereby reducing energy loss.

[0029] (3) Improving the uniformity of current density distribution: Through the improved sub-rib hole design and flow control mechanism, the present invention reduces the local high current density area, significantly improves the uniformity of current distribution, and helps to improve the stability and service life of the device.

[0030] (4) Improved thermal management performance: The optimized design of the present invention effectively reduces the local hot spot problem, making the heat generation in the flow field more uniform. At the same time, the use of materials with uniform thermal conductivity further enhances the heat transfer effect, thereby achieving more efficient thermal management performance.

[0031] (5) Enhanced system adaptability and reliability: The present invention uses thermally conductive materials with good stability and combines them with optimized geometric structure design to make the flow field structure more durable and suitable for a wider range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a comparison diagram of the principles of the improved interdigital jet flow field and the interdigital jet flow field for proton exchange membrane electrolyzer. The diagram shows the structural differences between MIJFF (improved interdigital jet flow field) and IJFF (interdigital jet flow field). MIJFF adds a new opening design in the jet plate to improve performance and uniformity.

[0033] Figure 2 The schematic diagram of the assembly of the improved interdigital jet flow field device for testing the proton exchange membrane electrolyzer, which includes an improved interdigital jet flow field plate for the anode, a serpentine flow field plate for the cathode, a membrane electrode assembly (MEA), a sealing gasket and an end plate structure. Each component closely cooperates to form a complete test system.

[0034] Figure 3 It is a schematic diagram of the physical comparison between the interdigital jet plate and the improved interdigital jet plate. The improved interdigital jet device adds a sub-rib opening area;

[0035] Figure 4 The figure is a schematic diagram of the physical comparison between the interdigital jet flow field and the improved interdigital jet flow field, both of which adopt the double-plate design of the interdigital plate and the jet plate;

[0036] Figure 5 Schematic diagram of the experimental results of the improved interdigitated jet flow field device test for the proton exchange membrane electrolyzer, the control groups are serpentine flow field (SFF), interdigitated flow field (IFF), and interdigitated jet flow field (IJFF);

[0037] Figure 6 This is a 3D schematic diagram of the simulation model, showing the 1:1 restoration effect of the simulation model and the actual experimental flow field. The simulation results are highly consistent with the experimental results, further verifying the rationality and effectiveness of the improved flow field design;

[0038] Figure 7 This is a schematic diagram of the uniformity results of the improved interdigital jet flow field device obtained through simulation modeling. The figure shows the uniformity of liquid saturation, temperature uniformity, and current density distribution, providing a reliable basis for evaluating the flow field optimization effect.

[0039] Figure 8It is a schematic diagram of the improved interdigital jet flow field device of the present invention. DETAILED DESCRIPTION

[0040] An improved interdigitated jet flow field device comprises a plurality of staggered jet channels, the jet channels are linear, and the channel spacing and size are designed to reduce flow resistance and pressure drop; the flow field is provided with under-rib openings to reduce gas retention and promote product discharge. The flow field is made of a material with uniform thermal conductivity, which can effectively improve thermal management performance.

[0041] In the water inlet channel, the holes under the ribs can provide water supply to the area under the ribs, which not only improves mass transfer but also increases the conductive area. Similarly, in the water outlet channel, the holes under the ribs can provide a channel for gas to be discharged in time, improving the phenomenon of gas accumulation. The holes under the ribs promote gas removal by creating additional channels for gas escape, minimizing the bottleneck of gas-liquid separation, especially at high current density, where gas accumulation will block active sites and reduce performance. These holes help reduce pressure drop, improve the efficiency of gas phase management, and allow liquid reactants to reach the reaction point more effectively.

[0042] Furthermore, the flow field is divided into two parts, the first part is the interdigitated flow field plate, the specific structure is shown in Table 1; the second part is the jet plate, the specific structure is shown in Table 2. The present invention significantly improves the uniform distribution of the fluid, the mass transfer efficiency and the uniformity of thermal management through the staggered arrangement of the jet channels and the optimized flow field design, thereby providing support for the efficient operation of the water electrolysis device.

[0043] Table 1 Geometric parameters of flow field plate

[0044]

[0045] Table 2 Geometric parameters of the jet plate

[0046]

[0047]

[0048] Reference Figure 1 As shown, the improved interdigitated jet flow field (MIJFF) optimizes the gas and liquid flow paths through the under-rib opening design based on the traditional interdigitated jet flow field (IJFF). Figure 1 IJFF and MIJFF are compared from a three-dimensional perspective. Compared with IJFF, MIJFF has additional openings under the ribs. There are two rows of openings under the ribs between each row of inlet jet holes and outlet jet holes, that is, each rib presses half of the two rows of openings under the ribs. This new jet plate structure increases the water supply to the porous electrode and promotes the discharge of the gas in the diffusion layer, improves the mass transfer under the ribs, and improves the uniformity of the current density.

[0049] like Figure 2 As shown, the improved interdigital jet flow field device of the present invention is used for a proton exchange membrane electrolyzer (PEMEC), mainly comprising an anode improved interdigital jet flow field plate, a cathode serpentine flow field plate, a membrane electrode assembly (MEA), a sealing gasket and an end plate structure, and the various components of the device are assembled in a stacked manner. The anode improved jet interdigital flow field plate and the cathode serpentine flow field plate are respectively located on both sides of the membrane electrode assembly, and are used to achieve efficient distribution of fluids and uniform mass transfer of reactants.

[0050] Reference Figure 3 As shown in the figure, the physical comparison between the improved interdigital jet plate and the traditional interdigital jet plate clearly shows the structural characteristics of the openings under the ribs. The design of the opening area under the ribs makes it easier for the gas to enter the deep part of the flow channel, effectively improving the local dead zone problem and improving the fluid mixing effect through the jet action.

[0051] like Figure 4 As shown in the figure, both the improved interdigital jet flow field and the interdigital flow field adopt a double-plate design of interdigital plate and jet plate to reduce the retention of reaction gas and improve exhaust efficiency. Its surface is composed of several parallel inlet and outlet channels, which are arranged alternately and separated by ribs to form a interdigital structure. Each inlet channel is directly connected to the collector, and the outlet channel is connected to the collector on the other side. The design of channel depth and width is optimized to ensure minimum pressure loss and uniform distribution of reactants. However, the improved interdigital jet flow field is more superior in function. The open hole structure under the rib reduces gas retention, improves the mass transfer efficiency in the reaction area, and significantly improves the current distribution uniformity and overall performance of the electrolyzer.

[0052] Reference Figure 5 As shown, the test experimental control groups include serpentine flow field (SFF), interdigitated flow field (IFF), and interdigitated jet flow field (IJFF). The experimental results show that the improved interdigitated jet flow field is superior to the traditional design in terms of performance and impedance.

[0053] like Figure 6 , 7 As shown in the figure, the simulation model of the improved interdigital jet flow field is constructed by 1:1 restored three-dimensional modeling technology to ensure the guiding significance of simulation data for experimental design. After adopting the improved interdigital flow field, the liquid saturation distribution on the anode side is more uniform, which effectively reduces local hot spots and gas retention phenomena, while improving the overall performance. Fluid simulation and experimental verification show that this design can significantly improve the uniformity of current density distribution and the overall performance of the electrolyzer.

[0054] The present invention proposes an improved composite flow field (MIJFF) based on the interdigitated jet flow field. The design of the improved interdigitated jet flow field is to improve the mass transfer under the ribs and promote the uniform distribution of various indexes. According to the results obtained, compared with the control group, after the MIJFF was applied to the anode of the proton exchange membrane electrolyzer, the uniformity of temperature, liquid saturation and current density distribution increased by 30.53%, 18.54% and 34.91%, respectively, and the vertical flow velocity at the flow channel increased by 60.6%. These results help to better understand the effect of the improved interdigitated jet flow field structure on the mass transfer and heat transfer performance of PEMEC. The optimized fluid path planning and the selection of materials with uniform thermal conductivity in the present invention significantly improve the fluid distribution, heat transfer and gas-liquid interface reaction performance in the flow field.

[0055] The present invention is suitable for the research and development of proton exchange membrane electrolyzers at laboratory and industrial scales, and has significant advantages in improving electrolyzer performance, reducing energy consumption and optimizing current distribution. By adjusting the flow field geometric parameters and test conditions, it can be further extended to the flow field design and optimization of other electrolyzers or electrochemical reactors.

[0056] The above description is a specific embodiment of the present invention, and is combined with a specific structure and a test method. However, those skilled in the art may make modifications or equivalent substitutions to the structure or method without departing from the spirit and scope of the present invention, and these modifications and substitutions should be deemed to fall within the scope of protection of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An improved interdigital jet flow field device, characterized in that: include: Double plate setting: including a finger plate and a jet plate, the two plates cooperate to achieve efficient forced convection; wherein the finger plate guides the fluid flow through a staggered fin structure, and the fins have the same width, spacing and thickness; the jet plate adopts a direct current channel, the jet aperture is 0.3-0.4mm, the depth is 0.1mm, and the center spacing between the jet holes is 1.5mm; the direct current channel ensures that the fluid flows in a straight jet mode; the jet plate cooperates with the finger plate to form an efficient fluid circulation through the action of the direct current jet; Sub-rib opening setting: Multiple small openings are evenly set in the sub-rib area, with a diameter of 0.2mm and a spacing of 1.5mm; The openings under the ribs are linked with the direct current channel to allow reactants and products to circulate in and out of the channel.

2. The improved interdigital jet flow field device according to claim 1, characterized in that: The interdigital plate and the jet plate are arranged in an adjacent mode, and the jet plate is closely attached to the membrane electrode assembly MEA.

3. The improved interdigital jet flow field device according to claim 1, characterized in that: The ratio of the fin length of the interdigitated plate to the channel length of the jet plate is 10:

1.

4. The improved interdigital jet flow field device according to claim 1, characterized in that: The fork finger plate and the jet plate are made of metal or composite material with high corrosion resistance and good thermal conductivity.

5. The improved interdigital jet flow field device according to any one of claims 1 to 4, characterized in that: The fin structure of the finger plate and the opening position of the jet plate are optimized through CFD simulation to ensure efficient fluid distribution and product discharge.

6. The improved interdigital jet flow field device according to claim 1, characterized in that: The opening is circular in design and is separated from the jet plate channel to form a flow mechanism in an independent space.

7. The improved interdigital flow field device for proton exchange membrane electrolyzer according to claim 1, characterized in that: The double-plate structure can be replaced modularly, and the size and opening layout of the fork plate and the jet plate can be adjusted according to actual working conditions.

8. A proton exchange membrane water electrolysis hydrogen production device, characterized by: The invention comprises the improved interdigital jet flow field device as described in any one of claims 1-7.

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