Anode segmented visual proton exchange membrane electrolyzer and method of use thereof

Abstract

The application provides an anode segmented visual proton exchange membrane electrolytic cell, which comprises an anode end plate, a sealing cover plate, a flow field separation plate, an anode segmented flow field plate, a five-in-one membrane electrode layer, a cathode bipolar plate, a stainless steel plate, an insulating gasket and a cathode end plate which are sequentially stacked. The sealing cover plate and the flow field separation plate are both transparent polycarbonate plates, the anode segmented flow field plate is composed of eight independent titanium flow field plates with anode tabs, the five-in-one membrane electrode layer is composed of eight independent membrane electrodes and a polyethylene terephthalate film, and the cathode bipolar plate is provided with eight independent flow channels on the surface, four groups of holes on each of the two side faces for inserting thermocouple probes and heating rods and four cathode tabs. The application can monitor and measure local parameters such as current, voltage and temperature, and can accurately control the temperature of reaction water; in addition, the sealing cover plate and the flow field separation plate are both made of transparent materials, which provides conditions for observing the flow pattern of the two-phase flow of the anode and analyzing the influence of the flow pattern on the performance of the electrolytic cell.

Description

Technical Field

[0001] This invention relates to an electrolytic cell and its application, and more particularly to an anode segmented visualization proton exchange membrane electrolytic cell, belonging to the field of electrochemical testing technology. Background Technology

[0002] Hydrogen energy, as a promising secondary energy source, has demonstrated tremendous application prospects due to its high energy density, wide range of sources and uses, and potential for large-scale energy storage. "Green hydrogen" produced through water electrolysis can achieve zero carbon emissions in hydrogen production. Among various water electrolysis hydrogen production technologies, proton exchange membrane (PEMEC) water electrolysis not only offers rapid start-up and shutdown and adjustable load, but also allows for flexible integration with renewable energy power generation systems such as wind and solar power, achieving efficient energy utilization. Furthermore, the relatively small size and flexible operation of the PEMEC cell give it a significant advantage in green hydrogen production. With the development of PEMEC technology, the measurement of its local parameters has received increasing attention. Studies have shown that during actual operation, the internal reactions of PEMEC are intricately coupled with multiple physical fields, including electric, thermal, and mass transfer fields. Specifically, the electric field drives the electrolysis reaction by applying voltage, the thermal field determines the temperature distribution, and the mass transfer field involves processes such as gas diffusion and proton transport. These complex interactions between physical fields further increase the complexity of system analysis. Therefore, under different operating conditions, the coupling effects between multiple physical fields must be comprehensively considered to accurately assess the operating status of PEMEC. To optimize the performance of the electrolyzer, the operating strategy must simultaneously focus on key parameters such as current density, voltage, two-phase flow pattern, and temperature. For many years, the measurement of these parameters has been an important topic in the field of PEMEC research, and it has profound significance for improving the performance and durability of the electrolyzer. Therefore, the following section will introduce the measurement techniques for current and temperature in proton exchange membrane electrolyzers, the observation techniques for two-phase flow, and the structure of existing electrolyzers.

[0003] First, we introduce the current measurement technique for proton exchange membrane electrolyzers: Van der Merwe et al. (VanderMerwe J, Uren K, Van Schoor G, et al. Characterisation tools development for PEM electrolyzers[J]. International Journal of Hydrogen Energy, 2014, 39(26): 14212-14221.) employed a method based on the permeability of magnetic materials to map current density in an electrolyzer with a serpentine flow field. This method uses a custom-designed device with 49 independent sensors to capture the spatial distribution of current density by measuring the magnitude of the local permeability of the induction coils, thus reflecting the local current density of the PEMEC. Cleghorn et al. (Cleghorn S JC, Derouin CR, Wilson MS, et al. Aprinted circuit board approach tomeasuring current distribution in a fuel cell[J]. Journal of Applied Electrochemistry, 1998, 28: 663-672.) were the first to attempt to measure the current density distribution in PEMFCs using PCB technology, but this required the fabrication of segmented anode flow fields and current collectors. Stumper et al. (Stumper J, Campbell SA, Wilkinson DP, et al. In-situ methods for the determination of current distributions in PEM fuel cells[J]. Electrochimica Acta, 1998, 43(24): 3773-3783.) proposed several methods to determine the current density distribution in fuel cells, including the partial MEA method, the current density mapping method, and the sub-cell method. Among them, the partial MEA method destroys the overall structure of the MEA by masking part of the MEA or making several partially catalyzed MEAs for independent testing; the current density mapping method places a passive graphite resistor between the flow plate and the current collector to measure the current density distribution; the sub-cell method arranges separate load controls on each separate sub-cell and the main cell, and is electrically isolated from each other, allowing independent adjustment of the cell current.In addition, Hall effect sensors can also be used to measure the current in fuel cells. Wieser et al. (Wieser C, Helmbold A, Gülzow EA new technique for two-dimensional current distribution measurements inelectrochemical cells[J]. Journal of Applied Electrochemistry, 2000, 30: 803-807.) used Hall effect sensors to measure the current in each part of the fuel cell.

[0004] Temperature distribution measurement technology has also been developed, including the work of He et al. (He S, Mench MM, Tadigadapa S. Thin film temperature sensor for real-time measurement of electrolyte temperature in a polymer electrolyte fuel cell[J]. Sensors and Actuators A: Physical, 2006, 125(2): 170-177.) who developed a thin-film gold thermistor using microfabrication technology for measuring 5cm... 2In-situ temperature measurements were performed on a Nafion-based fuel cell during operation. The thin-film temperature sensor exhibited a linear response over a temperature range of 20–100 °C. However, the performance of the fuel cell deteriorated significantly after the temperature sensor was embedded in the fuel cell. Lee et al. (Lee CY, Hsieh W J, Wu GW. Embedded flexible micro-sensors in MEA formeasuring temperature and humidity in a micro-fuel cell[J]. Journal of PowerSources, 2008, 181(2):237-243.) used micro-electromechanical systems (MEMS) technology to fabricate a micro-thin-film temperature sensor based on the principle of resistance temperature detector (RTD) to monitor the in-situ temperature in the flow channel fins and MEA of a micro fuel cell. Li et al. (Li, Y., Yang, G., Yu, S., Kang, Z., Talley, DA, Zhang, F.-Y., 2019. Direct thermal visualization of micro-scale hydrogen evolution reactions in proton exchange membrane electrolyzer cells. Energy Convers. Manag. 199, 111935) proposed an infrared thermal imaging method, using an infrared thermal imager and a high-speed visualization system to conduct comprehensive visualization experiments, capturing temperature changes on the cathode side of PEMEC. Ali et al. (Ali ST, J, Nielsen LP, et al. Thin film thermocouples for in situ membrane electrode assembly temperature measurements in a polybenzimidazole-based high temperature proton exchange membrane unit cell[J]. Journal of Power Sources, 2010, 195(15):4835-4841.) proposed the thermocouple probe method. Lee et al. (Lee CY, Chen CH, Li SC, et al. Development and application of flexible integrated microsensor as real-time monitoring tool in proton exchange membrane water electrolyzer[J]. Renewable Energy, 2019, 143:906-914.) developed a flexible integrated microsensor suitable for high-temperature electrochemical environments inside PEMEC using MEMS technology. They integrated micro temperature, flow, voltage, and current sensors into a 20 μm thick PI thin film substrate and used it as a protective layer to reduce the impact on the operation of the electrolyzer.

[0005] In the observation techniques of two-phase flow, J. Bedet et al. (Bedet J, Maranzana G, Leclerc S, et al. Magnetic resonance imaging of water distribution and production in a 6cm2 PEMFC under operation[J]. International Journal of Hydrogen Energy, 2008, 33(12): 3146-3149.) used nuclear magnetic resonance imaging (NMR) to observe water distribution in a PEMFC in operation, with the only compromise being the replacement of graphite (or metal) bipolar plates with PMMA supports, but this seems to be only applicable to small fuel cells. Ous and Arcumanis (Ous T, Arcumanis C. Visualization of water accumulation in the flow channels of PEMFC under various operating conditions[J]. Journal of Power Sources, 2009, 187(1): 182-189.) and Zhan et al. (Zhan Z, Wang C, Fu W, et al. Visualization of water transport in a transparent PEMFC[J]. International Journal of Hydrogen Energy, 2012, 37(1): 1094-1105.) proposed a transparent unit design that allows light to enter the flow channels and studied the effect of operating conditions on liquid water accumulation.

[0006] Regarding the structural design of the entire electrolyzer, Chinese patent CN216838210U discloses a proton exchange membrane water electrolyzer. This electrolyzer has a simple structure and small footprint, but due to the lack of transparent end plates, it is difficult to observe the two-phase flow at the anode. Furthermore, this electrolyzer lacks the function of monitoring and readjusting the temperature of the reaction water, making it difficult to stabilize the temperature near the set value. Chinese patent CN214937843U discloses a pure water hydrogen production PEM electrolyzer. This patent modularizes the electrolyzer, with sliding blocks fixedly connected to the shells on both sides of the electrolyzer, and a pull ring on the outside. This facilitates the installation and disassembly of the electrolysis units and ensures that they do not separate during the reaction, thus guaranteeing electrolysis efficiency. However, this patent results in an excessively large electrolyzer volume, which is unfavorable for high power density applications. Furthermore, due to its structure, it is difficult to measure the local current of a single unit electrolyzer, hindering subsequent performance analysis and improvement. Chinese patent CN216427426U discloses a top-screw reverse-pressure type PEM electrolyzer mechanism. This electrolyzer improves upon the traditional top-screw reverse-pressure type electrolyzer by using a connecting locking mechanism between clamping plates, eliminating the need for drilling holes in the electrolysis assembly to fix it between the two end plates. This successfully reduces the size of the electrolysis assembly and improves its utilization rate. However, this electrolyzer lacks internal monitoring of the reaction water temperature. The device, which measures feedback and makes secondary adjustments, cannot guarantee that the reaction water temperature will be accurately maintained near the set temperature parameters. Chinese patent CN115198293A discloses a proton exchange membrane electrolyzer containing a dual-functional porous layer. This electrolyzer is composed of several unit electrolyzers and partitions stacked longitudinally, which improves the gas-liquid transport capacity inside the electrolyzer, increases the volumetric power density, and effectively improves the performance of the electrolyzer. However, it is difficult to perform local current measurement on the unit electrolyzers to analyze their working performance. Furthermore, since this electrolyzer does not have transparent end plates, it is difficult to observe the flow pattern of the anode reaction water, making it difficult to further analyze and improve the performance of the electrolyzer.

[0007] Therefore, it is necessary to employ a suitable proton exchange membrane electrolyzer structure to accurately measure various parameters and dynamic behavior of PEMECs. This research not only contributes to a deeper understanding of the coupling effects of multiphysics fields but also facilitates real-time monitoring and fault diagnosis during operation. Furthermore, it can provide a reference for optimizing the structural design of PEMECs. Summary of the Invention

[0008] This invention provides an anode-segmented, visualized proton exchange membrane electrolyzer to monitor and measure local parameters such as current and temperature, and to visualize and analyze the anode two-phase flow. Furthermore, by adding thermocouples and heating rods to the cathode bipolar plates, the temperature of the reaction water is further monitored and managed, ensuring that the reaction water temperature remains near the set value to the maximum extent possible. The specific technical solution proposed in this invention is as follows:

[0009] A segmented, visualized proton exchange membrane electrolyzer, characterized by comprising, in sequence, an anode end plate, a sealing cover plate, a flow field partition plate, an anode segmented flow field plate, a five-in-one membrane electrode layer, a cathode bipolar plate, a stainless steel plate, an insulating gasket, and a cathode end plate; the five-in-one membrane electrode layer is composed of membrane electrodes and PET films, and the membrane electrodes are sequentially composed of an anode diffusion layer, a catalyst coating film, and a cathode diffusion layer; the sealing cover plate is provided with an anode feed water inlet, an anode water (gas) outlet, and a racetrack-shaped sealing groove; the flow field partition plate is engraved with an inward array of grooves, each groove is surrounded by a rectangular sealing groove and has a through hole punched diagonally for connecting two adjacent grooves. The grooves of the through holes correspond one-to-one with the positions of the racetrack-shaped sealing grooves on the sealing cover plate; the anode segmented flow field plate consists of 8 independent titanium flow field plates, and the inlet and outlet of the flow channels on the titanium flow field plates correspond one-to-one with the through holes on the flow field partition plate; the five-in-one membrane electrode consists of 8 independent hot-pressed membrane electrodes and PET film; the front of the cathode bipolar plate is engraved with a 4×2 flow channel array corresponding to the membrane electrode, and each flow channel is surrounded by a rectangular sealing groove, with through holes punched at both ends of the flow channel; the surface of the stainless steel plate is provided with the same racetrack-shaped sealing groove as the sealing cover plate, and the back is provided with a cathode water (gas) outlet corresponding to the water (gas) outlet of the cathode bipolar plate for discharging hydrogen and electroosmotic water.

[0010] Preferably, the groove array on the flow field separator plate is a 4×2 groove array, corresponding to the positions of the subsequent 8 independent titanium flow field plates, 8 independent hot-press film electrodes, the chamber on the PET film, the flow channel on the cathode bipolar plate, and the diffusion cavity on the anode and cathode pads.

[0011] Preferably, the titanium flow field plate is provided with an anode tab, which extends outward from the electrolytic cell.

[0012] Preferably, the PET film has a cavity array corresponding to the membrane electrode through it along the thickness direction, and the membrane electrode is embedded in the cavity;

[0013] Preferably, the cathode bipolar plate has four symmetrically distributed sets of holes for inserting thermocouple probes and heating rods on each of its two sides, as well as four tabs, and a fin is provided in the middle of the upper end face.

[0014] Preferably, the segmented visual proton exchange membrane electrolyzer further includes an anode pad and a cathode pad; the pad has a diffusion cavity corresponding to the membrane electrode through it along the thickness direction, and the membrane electrode is embedded in the diffusion cavity.

[0015] The present invention also discloses an electrolyzer application method, which is based on the above-mentioned anode segmented visual proton exchange membrane electrolyzer.

[0016] Beneficial effects

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) The present invention uses a segmented design for the anode, dividing the anode into eight blocks, and each anode segment flow field plate is provided with an anode tab extending out of the electrolytic cell. The advantage is that it effectively reduces experimental consumables and allows for the measurement and monitoring of local current and voltage parameters.

[0019] (2) This invention uses transparent polycarbonate plates for both the sealing cover and the flow field partition plate, and both plates have sealing grooves. The advantage is that, compared to the transparent acrylic end plates used in typical visual electrolytic cells, polycarbonate plates have higher mechanical strength, can withstand high-temperature and high-pressure working environments, and have better applicability. Furthermore, the transparent sealing cover and flow field partition plate also provide conditions for observing the two-phase flow in the anode flow field. In addition, the grooves on the flow field partition plate, combined with the racetrack-shaped sealing grooves on the sealing cover plate, ensure the airtightness of the electrolytic cell.

[0020] (3) The present invention has four sets of symmetrically distributed holes on each of the two sides of the cathode bipolar plate for inserting thermocouple probes and heating rods. The advantage is that it allows for the measurement of the battery operating temperature and can help adjust the temperature of the reaction water, ensuring that the temperature of each part of the electrolyzer is uniform and stable near the set parameter value.

[0021] (4) The present invention has 19 through holes for assembly bolts, which are evenly distributed around the flow field and do not pass through the anode segment flow field plate. The advantage is that it improves the uniformity of pressure distribution in the electrolytic cell and minimizes the impact of the assembly process on the internal pressure distribution of the electrolytic cell.

[0022] (5) The outer surface of the bolts used in this invention is electrically insulated. The advantage is that it can effectively prevent battery short circuits.

[0023] (6) The membrane electrode of the present invention is a five-in-one membrane electrode, that is, using a PET film as a carrier, with a 4×2 diffusion chamber etched on it, and eight membrane electrodes are placed in the chambers and uniformly hot-pressed, so that each gas diffusion layer is uniformly and tightly bonded to its corresponding catalyst coating film. The advantage is that this method allows each membrane electrode to accurately correspond to its corresponding flow field region, which greatly facilitates the assembly of the membrane electrode layers, improves the assembly success rate, strengthens the airtightness of the core reaction area, reduces gas cross-contamination, and avoids short circuits. In addition, this method improves conductivity, and compared with traditional single membrane electrodes, the 4×2 membrane electrode array provides the possibility to perform various electrochemical tests on local areas within the plane of the electrolyzer.

[0024] (7) The present invention uses fluororubber gaskets on both the cathode and anode sides. The advantage is that it can further ensure the sealing of the electrolytic cell, and the addition of gaskets helps to eliminate the thickness difference caused by the membrane electrode.

[0025] (8) Both the flow field partition plate and the anode segmented flow field plate of the present invention are produced by an integral cutting process. The advantage is that it can ensure the surface flatness and fit of the two plates after nesting to the greatest extent.

[0026] (9) The electrolytic cell sealing structure used in this invention is a high-pressure resistant structure. The advantage is that, compared with ordinary electrolytic cells, the electrolytic cell of this invention can withstand a wider pressure range, and can work stably under continuous high pressure without worrying about leakage, thereby realizing the measurement of parameters such as local current density and temperature of the electrolytic cell under a wider pressure range. Attached Figure Description

[0027] Figure 1 An exploded view of a segmented, visual proton exchange membrane electrolyzer with anodes;

[0028] Figure 2a This is an assembly position diagram of the anode side components of the electrolytic cell, showing that the eight titanium flow field plates are matched with the groove array on the flow field partition plate;

[0029] Figure 2b This is a schematic diagram of the assembly of the flow field partition plate and the anode segment flow field plate, which can intuitively reflect their fit and the flow of water (gas) reacting on the anode side;

[0030] Figure 3a This is a schematic diagram of the structure of the five-in-one film electrode layer;

[0031] Figure 3b This is a schematic diagram of a single membrane electrode.

[0032] Figure 4a This is a front view of the cathode bipolar plate;

[0033] Figure 4b This is a side-rear view of the cathode bipolar plate;

[0034] Figure 5 Here is a diagram showing the recommended bolt assembly sequence;

[0035] Figure 6 This is a physical image of a segmented, visualized proton exchange membrane electrolyzer with an anode.

[0036] Figure 7 This is a system structure diagram of a pre-exchange membrane electrolyzer in operation. Detailed Implementation

[0037] Reference Figure 1As shown, the segmented anode visualization proton exchange membrane electrolyzer comprises, in sequence, an anode end plate, a sealing cover plate, a flow field partition plate, an anode segmented flow field plate, a polytetrafluoroethylene gasket, a five-in-one membrane electrode layer, a cathode bipolar plate, a stainless steel plate, an insulating gasket, and a cathode end plate. The transparent sealing end plate and flow field partition plate provide the means to observe the two-phase flow of the anode flow field during battery operation.

[0038] The thickness of the anode and cathode gaskets matches the thickness of their corresponding gas diffusion layers. This ensures the diffusion layer has sufficient compression to improve electrical contact while eliminating unnecessary height differences to enhance the electrolytic cell's sealing. A 4×2 diffusion cavity array is formed throughout the gasket along its thickness direction. The size of each diffusion cavity corresponds to the size of the membrane electrode, and the diffusion layer is embedded within the diffusion cavity, without affecting the contact between the membrane electrode and the flow field plate. The gasket not only facilitates the installation and fixation of the membrane electrode but also acts as a sealing ring at its edges.

[0039] In addition, the surfaces of the 19 bolts used to fix the inside of the electrolytic cell are insulated to prevent short circuits in the electrolytic cell, and the bolts do not pass through the anode segment flow field plate, thereby reducing the impact of assembly operations on the flow field plate.

[0040] like Figure 2a As shown, the anode feed water inlet and anode water (gas) outlet on the sealing cover plate correspond to the water inlet and water (gas) outlet holes on the flow field partition plate, respectively. The flow field partition plate is engraved with a 4×2 groove array matching the size of the anode segmented flow field plate for embedding. Rectangular sealing grooves surround the grooves to ensure the electrolytic cell's airtightness. Furthermore, through holes are punched diagonally in the grooves, corresponding to the water inlet and outlet holes of the flow channels on the anode segmented flow field plate. Adjacent through holes are connected by grooves to connect the water and gas flow within the electrolytic cell. The positions of these grooves correspond to the racetrack-shaped sealing grooves on the sealing cover plate, ensuring the electrolytic cell's airtightness. The anode tabs on the anode segmented flow field plate are used for connecting the positive electrode feed wire and the positive electrode feedback wire.

[0041] like Figure 2b As shown, the water inlet on the flow field partition plate corresponds to the flow channel inlet on the first titanium flow field plate. The reacting water enters the flow channel inlet on the first titanium flow field plate through the water inlet and flows through the flow channel to the outlet of the first titanium flow field plate. Then, it flows through the groove on the flow field partition plate and into the flow channel inlet on the second titanium flow field plate. This cycle continues until it finally flows to the outlet on the last titanium flow field plate. The outlet on the last titanium flow field plate corresponds to the water (gas) outlet on the flow field partition plate. The remaining reacting water and the generated oxygen flow out of the electrolytic cell through this outlet.

[0042] like Figure 3aAs shown, the five-in-one membrane electrode layer in the proton exchange membrane electrolyzer includes eight independent membrane electrodes and a PET film. The active area of ​​a single membrane electrode is 18 × 22 mm. 2 A 4×2 array is formed, with the PET film having a cavity array corresponding to the membrane electrode through it along the thickness direction. The area of ​​a single diffusion cavity is 23×27 mm. 2 The membrane electrode is embedded in the cavity, and the use of PET film helps to install and position the membrane electrode.

[0043] like Figure 3b As shown, each membrane electrode is prepared by hot pressing a catalyst-coated membrane and two gas diffusion layers;

[0044] like Figure 4a As shown, the front of the cathode bipolar plate is engraved with a flow channel matrix corresponding to the membrane electrode matrix, and each flow channel is surrounded by a rectangular sealing groove. There are four cathode tabs on each of the two sides of the cathode bipolar plate for connecting the negative electrode to the wire. Furthermore, because the cathode tabs on the cathode bipolar plate have a small area, a fin is provided in the middle of the upper surface of the cathode bipolar plate for connecting the negative electrode feedback line, which, together with the positive electrode feedback line on the anode tab, measures the current and voltage.

[0045] like Figure 4b As shown, each of the two outer walls of the cathode bipolar plate has four sets of heating holes and thermocouple holes. The heating holes are used to insert heating elements such as heating rods, and the thermocouple holes are used to insert thermocouples to monitor and heat the electrode plate, thereby controlling the temperature according to the requirements of water electrolysis. In addition, there are two water (gas) outlet holes at the rear of the cathode bipolar plate.

[0046] like Figure 5 As shown, the recommended bolt assembly sequence is indicated. This assembly sequence helps to reduce damage caused by uneven assembly pressure and improve the uniformity of assembly pressure in the electrolytic cell.

[0047] like Figure 6 As shown, when testing the voltage and current of the electrolytic cell, the positive electrode supply wire and the positive electrode feedback wire are connected to the positive electrode tab of the anode segmented flow field plate, the negative electrode supply wire is connected to the negative electrode tab of the cathode bipolar plate, and the negative electrode feedback wire can be connected to the negative electrode tab of the cathode bipolar plate or to the fins above the cathode bipolar plate.

[0048] When connecting the positive and negative feed wires, connect the positive feed wire to the positive tab of the anode segment flow field plate and the negative tab of the cathode bipolar plate, which are positioned opposite each other, to ensure that the voltage travels the same distance through the medium. Additionally, it is recommended to wrap the inlet pipe with insulating material to reduce heat loss caused by heat exchange between the reacting water and the environment.

[0049] like Figure 7As shown, in the power supply circuit, voltage is supplied to the wires through a multi-channel DC power supply via positive and negative terminals. The real-time measured voltage and current data are then collected by the positive and negative feeders and sent to the computer. In the temperature measurement and control system, the temperature controller not only monitors and controls the temperature of the preheater but also monitors the temperature inside the electrolytic cell through thermocouples and heating rods on the cathode bipolar plate, and readjusts the temperature to ensure it falls more precisely near the given value. In the water supply and exhaust system, purer deionized water is used for the experiment. The deionized water is heated by a peristaltic pump and then enters the electrolytic cell for electrolysis. Finally, the remaining water and generated oxygen are discharged through the anode water (gas) outlet on the sealed cover. Electroosmotic water and hydrogen are discharged through the cathode water (gas) outlet on the stainless steel plate. Furthermore, a digital camera system in front of the electrolytic cell is used to monitor the anode two-phase flow state in real time. The lighting provides a strong illumination environment for the camera, and a high-speed camera records the flow pattern of the two-phase flow in the anode channel of the electrolytic cell.

[0050] The working process of the segmented visual proton exchange membrane electrolyzer of this invention is as follows: The reaction water is deionized water, which is heated to the set temperature by a peristaltic pump and then enters the anode water inlet on the sealed cover plate. It then enters the inlet of the first titanium flow field plate through the water inlet hole on the flow field partition plate, flows through the flow channel, reaches the outlet of the first titanium flow field plate, and then flows through the groove on the flow field partition plate into the inlet of the second titanium flow field plate. This cycle continues until it finally flows to the outlet of the last titanium flow field plate. The outlet of the last titanium flow field plate is opposite to the water (gas) outlet on the flow field partition plate and the anode water (gas) outlet on the sealed cover plate. The remaining reaction water and the generated oxygen flow out of the electrolyzer from here. During this process, the eight sub-membrane electrodes on the five-in-one membrane electrode simultaneously perform water electrolysis: water on the titanium flow field plate passes through the anode diffusion layer to the catalyst coating membrane, where it undergoes an oxidation reaction to generate oxygen and release hydrogen ions (protons). The oxygen and unreacted water continue to flow downstream along the channels and trenches until they are discharged from the anode water (gas) outlet on the sealed cover plate. The generated protons pass through the proton exchange membrane and undergo a reduction reaction at the corresponding cathode to generate hydrogen gas. This hydrogen gas, along with the electroosmotic water, flows downward within the flow field of the cathode bipolar plate and is finally discharged from the cathode water (gas) outlet on the stainless steel plate. During this process, thermocouples and heating rods on the cathode bipolar plate monitor and adjust the temperature of the electrolytic cell to ensure the uniformity of the reaction temperature and stabilize the reaction temperature near a given value.

[0051] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. An anode segmented visualized proton exchange membrane electrolyzer comprising anode end plate, sealing cover plate, flow field separator plate, anode segmented flow field plate, five-in-one membrane electrode layer, cathode bipolar plate, stainless steel plate, insulating gasket and cathode end plate stacked in sequence; characterized in that: The five-in-one membrane electrode layer comprises eight independent membrane electrodes and a PET film, and the active area of a single membrane electrode is 18*22 mm 2 , which forms a 4*2 array, and the PET film is provided with a cavity array corresponding to the membrane electrodes in the thickness direction, and the area of a single diffusion cavity is 23*27 mm 2 , and the membrane electrode is embedded in the cavity; the membrane electrode is composed of an anode diffusion layer, a catalyst coating film and a cathode diffusion layer in sequence.

2. The anode segmented visualized proton exchange membrane electrolyzer of claim 1, wherein: The flow field separation plate is made of transparent polycarbonate material, which is engraved with an inward 4x2 groove array corresponding to the anode segmented flow field plate.

3. The segmented anode visualized proton exchange membrane electrolyzer of claim 2, wherein: The groove ring has a rectangular sealing groove, and the diagonal of the groove is punched with a through hole corresponding to the water inlet and outlet hole on the anode separation flow field plate.

4. The segmented anode visualized proton exchange membrane electrolyzer of claim 3, wherein: The through hole is connected with the through hole on the adjacent groove by a groove; the groove position corresponds to the runway type sealing groove on the sealing cover plate.

5. The anode segmented visualized proton exchange membrane electrolyzer of claim 1, wherein: The anode segmented flow field plate is composed of 8 independent titanium flow field plates corresponding to the groove array on the anode segmented flow field plate.

6. The segmented anode visualized proton exchange membrane electrolyzer of claim 5, wherein: The surface of the titanium flow field plate is engraved with flow channel, and the titanium flow field plate is provided with anode lug; the anode lug extends out of the anode segmented proton exchange membrane electrolytic cell.

7. The anode segmented visualized proton exchange membrane electrolyzer of claim 1, wherein: The PET film is provided with a cavity array corresponding to the membrane electrode along the thickness direction, and the membrane electrode is embedded in the cavity.

8. The anode segmented visualized proton exchange membrane electrolyzer of claim 1, wherein: The cathode bipolar plate is engraved with a 4x2 flow channel array corresponding to the position of the membrane electrode on the front surface, and each flow channel is surrounded by a rectangular sealing groove; Each of the two side surfaces of the cathode bipolar plate is provided with 4 groups of symmetrically distributed holes for inserting thermocouple probes and heating rods; Each of the two side surfaces of the cathode bipolar plate is provided with 4 cathode lugs symmetrically distributed, and a fin is arranged in the middle of the upper end surface.

9. The segmented anode visualized proton exchange membrane electrolyzer of claim 4, wherein: The electrolytic cell further comprises anode gaskets and cathode gaskets; the anode gaskets and cathode gaskets are provided with diffusion cavities corresponding to the membrane electrode along the thickness direction, and the size and position of the diffusion cavities correspond to the membrane electrode.

10. A method of electrolysis application based on the segmented visualized proton exchange membrane electrolyzer of the anode according to any one of claims 1-9, characterized in that the reaction The water is deionized water, which is heated to a set temperature by a peristaltic pump through a preheater, then enters the anode water inlet on the sealing cover plate, then enters the inlet of the first titanium flow field plate through the through hole on the flow field separation plate, flows through the flow channel, reaches the outlet of the first titanium flow field plate, then flows into the through hole of the second titanium flow field plate through the groove on the flow field separation plate, and so on, and finally flows out of the electrolytic cell through the outlet of the last titanium flow field plate; the outlet of the last titanium flow field plate is opposite to the anode water outlet on the sealing cover plate, and the remaining reaction water and oxygen generated together flow out of the electrolytic cell; in this process, the eight sub-membrane electrodes on the five-in-one membrane electrode simultaneously perform electrolytic water work: the water on the titanium flow field plate reaches the catalyst coating film through the anode diffusion layer, performs oxidation reaction, generates oxygen and releases hydrogen ions, and the oxygen and unreacted water continue to flow downstream along the flow channel and groove until they are discharged from the anode water outlet on the sealing cover plate; the generated protons pass through the proton exchange membrane and reduce in the corresponding cathode to generate hydrogen gas, which flows downward in the flow field of the cathode bipolar plate together with the electroosmotic water, and finally flows out from the two cathode water outlets on the stainless steel plate; in this process, the thermocouple and heating rod on the cathode bipolar plate detect and secondarily regulate the temperature of the electrolytic cell to ensure the uniformity of the reaction temperature and stabilize the reaction temperature near the given value.

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