Anode sectional type visual proton exchange membrane electrolytic cell and application method thereof

Abstract

The invention provides an anode sectional type visual proton exchange membrane electrolytic cell. The anode sectional type visual proton exchange membrane electrolytic cell comprises an anode end plate, a sealing cover plate, a flow field partition plate, an anode sectional flow field plate, a five-in-one membrane electrode layer, a cathode bipolar plate, a stainless steel plate, an insulating spacer and a cathode end plate which are sequentially stacked. The sealing cover plate and the flow field partition plate are 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 glycol terephthalate film, the surface of the cathode bipolar plate is provided with eight independent flow channels, and the flow channels are communicated with the flow field partition plate. And four groups of holes for inserting thermocouple probes and heating rods and four cathode tabs are reserved on each of the two side surfaces. Local parameters such as current, voltage and temperature can be monitored and measured, and the temperature of reaction water can be accurately controlled; in addition, the sealing cover plate and the flow field partition plate are both made of transparent materials, and conditions are provided for observing the flow pattern of the anode two-phase flow and analyzing the influence of the flow pattern on the performance of the electrolytic cell.

Description

Technical Field

[0001] The invention relates to an electrolytic cell and application thereof, in particular to an anode segmented visualized proton exchange membrane electrolytic cell, belonging to the technical field of electrochemical testing. Background Art

[0002] As a highly anticipated secondary energy source, hydrogen energy has shown great application prospects due to its high energy density, wide range of sources and uses, and potential in large-scale energy storage. "Green hydrogen" produced by water electrolysis can achieve zero carbon emissions in hydrogen production. Among the many water electrolysis hydrogen production technologies, proton exchange membrane water electrolysis hydrogen production technology not only has rapid start and stop and adjustable load, but can also be flexibly combined with renewable energy power generation systems such as wind power and solar energy to achieve efficient energy utilization. In addition, the proton exchange membrane water electrolyzer (PEMEC) has a relatively small volume and flexible operation, which also makes it more advantageous in the production of green hydrogen. With the development of PEMEC technology, the measurement of its local parameters has also received increasing attention. Studies have shown that in the actual operation of PEMEC, there is a complex coupling relationship between its internal reaction and multiple physical fields such as electric field, thermal field, and mass transfer field. 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. The complex interaction between these physical fields further increases the complexity of system analysis. Therefore, under different operating conditions, the coupling effects between multiple physical fields need to be comprehensively considered to accurately evaluate the operating status of PEMEC. In order to optimize the performance of the electrolyzer, the operating strategy must pay attention to 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 has far-reaching significance for improving the performance and durability of electrolyzers. Therefore, the following will introduce the measurement technology of current and temperature in proton exchange membrane electrolyzers, the observation technology of two-phase flow, and the structure of existing electrolyzers.

[0003] First, the current measurement technology of the proton exchange membrane electrolyzer is introduced: Van der Merwe et al. (VanderMerwe J, Uren K, Van Schoor G, et al. Characterization tools development for PEM electrolysers [J]. International Journal of Hydrogen Energy, 2014, 39 (26): 14212-14221.) used a method based on the magnetic permeability of magnetic materials to map the current density in an electrolyzer with a serpentine flow field. This method uses a custom device with 49 independent sensors to capture the spatial distribution of current density by sensing the size of the local magnetic permeability of the coil to reflect the local current density of the PEMEC. Cleghorn et al. (Cleghorn S JC, Derouin CR, Wilson MS, et al. A printed circuit board approach to measuring current distribution in a fuel cell [J]. Journal of Applied Electrochemistry, 1998, 28: 663-672.) first attempted to use PCB technology to measure the current density distribution in PEMFC, but this required the manufacture of segmented anode flow fields and current collector plates. 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 a variety of methods to determine the current density distribution in fuel cells, including partial MEA method, current density mapping method and sub-unit method. Among them, the partial MEA method destroys the overall structure of the MEA by covering up partial areas of the MEA, or making several partially catalytic MEAs for independent testing; the current density mapping method places a passive graphite resistor between the flow plate and the current collecting plate to measure the current density distribution; the sub-battery method arranges separate load controls on each separated sub-battery and the main battery, and is electrically isolated from each other, allowing independent adjustment of each battery current.In addition, Hall effect sensors can also be used to measure the current of fuel cells. Wieser et al. (Wieser C, Helmbold A, Gülzow EA new technique for two-dimensional current distribution measurements in electrochemical cells [J]. Journal of Applied Electrochemistry, 2000, 30: 803-807.) used Hall effect sensors to measure the current of each part of the fuel cell.

[0004] Temperature distribution testing technology has also been developed, including 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.) developed a thin film gold thermistor using micromachining technology to measure the temperature of 5 cm 2In-situ temperature measurement of Nafion-based fuel cells during operation. The thin film temperature sensor has a linear response in the temperature range of 20–100°C. However, after the temperature sensor was embedded in the fuel cell, the performance of the fuel cell deteriorated significantly. 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 Power Sources, 2008, 181 (2): 237-243.) used micro-electromechanical systems (MEMS) technology and fabricated a micro-thin film temperature sensor based on the principle of resistance temperature detector (RTD) to monitor the in-situ temperature in the micro fuel cell flow channel ribs and MEA. 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 a comprehensive visualization experiment and capture the 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 a 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.) used MEMS technology to develop a flexible integrated microsensor suitable for high temperature electrochemical environment inside PEMEC, integrating micro temperature, flow, voltage and current sensors into a 20 μm thick PI film substrate and using it as a protective layer to reduce the impact on the operation of the electrolyzer.

[0005] In the two-phase flow observation technology, 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 the water distribution in the operating PEMFC. The only concession was that the graphite (or metal) bipolar plate was replaced by a PMMA bracket, but it seems to be only applicable to small fuel cells. Ous and Arcoumanis (Ous T, Arcoumanis C. Visualisation 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 cell design that allows light to enter the flow channel 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, which has a simple structure and occupies a small area, but due to the lack of a transparent end plate, it is difficult to observe the two-phase flow of the anode. In addition, the electrolyzer does not have the function of monitoring and re-adjusting the temperature of the reaction water, which makes it difficult for the temperature of the reaction water to stabilize near the set value; Chinese patent CN214937843U discloses a pure water hydrogen production PEM electrolyzer, which unitizes the electrolyzer, and has sliding blocks fixedly connected to the shells on both sides of the electrolyzer, and a pull ring is set on the outside. It is conducive to the installation and disassembly of the electrolysis unit cell, and also ensures that it will not separate during the reaction, ensuring the electrolysis efficiency. However, this patent will cause the electrolytic cell to be too large and is not conducive to high power density conditions. In addition, due to its structure, it is difficult for the electrolytic cell to measure the local current of a single unit electrolytic cell, which is not conducive to subsequent performance analysis and improvement; Chinese patent CN216427426U discloses a top-wire back-pressure PEM electrolytic cell mechanism, which improves the installation and fixing method of the traditional top-wire back-pressure electrolytic cell. By connecting the clamping plates, the electrolytic component can be fixed between the two end plates without drilling holes in the electrolytic component, which successfully reduces the volume of the electrolytic component and improves the component utilization rate, but the electrolytic cell does not monitor the reaction water temperature. A device for measuring feedback and performing secondary adjustment is provided, so it is impossible to ensure that the reaction water temperature is accurately maintained near the set temperature parameters; Chinese patent CN115198293A discloses a proton exchange membrane electrolyzer comprising a dual-functional porous layer, which is composed of a plurality of unit electrolyzers and partitions stacked longitudinally, thereby improving the gas-liquid transmission capacity inside the electrolyzer, increasing the volume power density, and effectively improving the performance of the electrolyzer, but it is difficult to perform local current measurement of the unit electrolyzer of the electrolyzer to analyze its working performance, and because the electrolyzer does not have a transparent end plate, it is difficult to observe the flow pattern of the anode reaction water, and it is difficult to further analyze and improve the performance of the electrolyzer.

[0007] Therefore, it is necessary to use a suitable proton exchange membrane electrolyzer structure to accurately measure the various parameters and dynamic behaviors of PEMEC. This study not only helps to better understand the coupling of multiple physical fields, but also facilitates real-time monitoring and fault diagnosis during operation. In addition, it can also provide a reference for optimizing the structural design of PEMEC. Summary of the invention

[0008] The present invention provides an anode segmented visualized proton exchange membrane electrolyzer to realize monitoring and measurement of local parameters such as local current and temperature, and visualized analysis of anode two-phase flow; and by adding thermocouples and heating rods in the cathode bipolar plate, the temperature of the reaction water is monitored and managed again, and the reaction water temperature is guaranteed to be near the set value to the greatest extent. The specific technical solutions proposed by the present invention are as follows:

[0009] An anode segmented visualized proton exchange membrane electrolyzer, characterized in that it comprises an anode terminal plate, a sealing cover plate and a flow field separator 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 terminal plate which are stacked in sequence; the five-in-one membrane electrode layer is composed of a membrane electrode and a PET film, and the membrane electrode is composed of an anode diffusion layer, a catalyst coating membrane and a cathode diffusion layer in sequence, an anode water inlet, an anode water (gas) outlet and a runway-type sealing groove are provided on the sealing cover plate, and an inward groove array is engraved on the flow field separator plate, 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 by one to the positions of the racetrack-shaped sealing grooves on the sealing cover plate; the anode segmented flow field plate is composed of 8 independent titanium flow field plates, and the inlets and outlets of the flow channels on the titanium flow field plates correspond one by one to the through holes on the flow field separator plate; the five-in-one membrane electrode is composed of 8 independent hot-pressed membrane electrodes and PET films; a 4×2 flow channel array corresponding to the membrane electrode is engraved on the front of the cathode bipolar plate, each flow channel is surrounded by a rectangular sealing groove, and through holes are punched at both ends of the flow channel; the surface of the stainless steel plate is provided with a racetrack-shaped sealing groove identical to the sealing cover plate, and a cathode water (gas) outlet corresponding to the water (gas) outlet hole of the cathode bipolar plate is provided on the back 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-pressed membrane electrodes, the chambers on the PET film, the flow channels on the cathode bipolar plate and the diffusion chambers on the anode and cathode gaskets.

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

[0012] Preferably, the PET film is provided with a cavity array corresponding to the membrane electrode in a thickness direction, and the membrane electrode is embedded in the cavity;

[0013] Preferably, the two side surfaces of the cathode bipolar plate are each provided with four symmetrically distributed groups of holes for inserting thermocouple probes and heating rods and four pole ears, and a fin is also provided in the middle of the upper end surface.

[0014] Preferably, the anode segmented visualized proton exchange membrane electrolyzer further comprises an anode gasket and a cathode gasket; the gasket is penetrated along the thickness direction to form a diffusion cavity corresponding to the membrane electrode, and the membrane electrode is embedded in the diffusion cavity.

[0015] The invention also discloses an application method of an electrolytic cell, wherein the electrolytic cell is based on the above-mentioned anode segmented visualized proton exchange membrane electrolytic cell.

[0016] Beneficial Effects

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

[0018] (1) The present invention adopts a segmented design in the design of the anode, dividing the anode into eight blocks, and each anode segment flow field plate is provided with an anode pole ear extending out of the electrolytic cell. The advantage is that the experimental consumables are effectively reduced, and local current and voltage parameters can be measured and monitored.

[0019] (2) The present invention uses a transparent polycarbonate plate in the selection of materials for the sealing cover plate and the flow field separator plate, and sealing grooves are left on the sealing cover plate and the flow field separator plate. The advantage is that compared with the transparent acrylic end plate used in general visual electrolytic cells, the polycarbonate plate has higher mechanical strength, can withstand high temperature and high pressure working environment, has better applicability, and the transparent sealing cover plate and flow field separator plate also provide conditions for observing the two-phase flow in the anode flow field. In addition, the grooves on the flow field separator plate are matched with the racetrack-shaped sealing grooves on the sealing cover plate to ensure the airtightness of the electrolytic cell.

[0020] (3) The present invention provides symmetrically distributed four groups of holes for inserting thermocouple probes and heating rods on both sides of the cathode bipolar plate. The advantage is that it allows the battery operating temperature to be measured and can assist in adjusting the temperature of the reaction water to ensure that the temperature of each part of the electrolytic cell is uniform and stable near the set parameter value.

[0021] (4) The present invention has 19 assembly bolt through holes, which are evenly arranged around the flow field and do not pass through the anode segmented flow field plate. The advantage is that the uniformity of the pressure distribution in the electrolytic cell is improved and the influence of the assembly process on the pressure distribution inside the electrolytic cell is minimized.

[0022] (5) The outer surface of the bolt used in the present invention is electrically insulated, which has the advantage of effectively preventing the battery from short-circuiting.

[0023] (6) The membrane electrode of the present invention is a five-in-one membrane electrode, that is, a PET film is used as a carrier, and a 4×2 diffusion chamber is engraved on it. Eight membrane electrodes are placed in the chamber and uniformly hot-pressed once, so that each gas diffusion layer and its corresponding catalyst coating membrane are evenly and tightly fitted. The advantage is that this method allows each membrane electrode to accurately correspond to its corresponding flow field area, greatly facilitates the assembly of the membrane electrode layer, improves the assembly success rate, strengthens the airtightness of the core reaction area, reduces gas crossover, and avoids the occurrence of short circuits. In addition, this method improves the electrical conductivity, and compared with the traditional single-piece membrane electrode, the 4×2 membrane electrode array makes it possible 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 side and the anode side. The advantage is that the sealing of the electrolytic cell can be further ensured, and the addition of the gasket helps to eliminate the thickness difference caused by the membrane electrode.

[0025] (8) The flow field separator plate and the anode segmented flow field plate of the present invention are both cut in one piece, which has the advantage of ensuring that the surfaces of the two plates are flat and close fitting after being nested.

[0026] (9) The electrolytic cell sealing structure adopted in the present invention is a high-pressure resistant structure. The advantage is that, compared with a general electrolytic cell, the electrolytic cell of the present invention can withstand a wider pressure range and can work stably under a continuous high pressure without worrying about leakage, thereby realizing the measurement of local current density, temperature and other parameters of the electrolytic cell under a wider pressure range. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a three-dimensional exploded diagram of a segmented anode-visualized proton exchange membrane electrolyzer;

[0028] Figure 2a This is the assembly position diagram of the anode side components of the electrolyzer, where the eight titanium flow field plates match the groove array on the flow field separator plate;

[0029] Figure 2b It is a schematic diagram of the assembly of the flow field separator plate and the anode segmented flow field plate, which can intuitively reflect their matching conditions and the flow of the reaction water (gas) on the anode side;

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

[0031] Figure 3b Schematic diagram of the structure of a single membrane electrode;

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

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

[0034] Figure 5 The following is a diagram of the recommended bolt assembly sequence;

[0035] Figure 6 A physical picture of a proton exchange membrane electrolyzer with segmented anode visualization;

[0036] Figure 7 This is the system structure diagram of the operation of the proton exchange membrane electrolyzer. DETAILED DESCRIPTION

[0037] Reference Figure 1As shown, the anode segmented visualized proton exchange membrane electrolyzer includes an anode end plate, a sealing cover plate, a flow field separator 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, which are stacked in sequence. Among them, the transparent sealing end plate and the flow field separator plate provide conditions for observing the two-phase flow of the anode flow field in the working state of the battery.

[0038] The thickness of the cathode and anode gaskets matches the thickness of the corresponding gas diffusion layer, ensuring that the diffusion layer has a certain amount of compression to improve electrical contact while eliminating unnecessary height differences to improve the sealing of the electrolyzer. The gasket is penetrated along the thickness direction with a 4×2 diffusion cavity array. The size of the diffusion cavity corresponds to the size of the membrane electrode. The diffusion layer is embedded in the diffusion cavity and does not affect the contact between the membrane electrode and the flow field plate. The setting of the gasket not only facilitates the installation and fixation of the membrane electrode, but also plays the role of a sealing ring at its edge.

[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 segmented flow field plate, thereby reducing the impact of assembly operations on the flow field plate.

[0040] like Figure 2a As shown, the anode water inlet and anode water (gas) outlet on the sealing cover plate correspond to the water inlet and water (gas) outlet on the flow field separator plate, respectively. The flow field separator plate is engraved with a 4×2 groove array that matches the size of the anode segmented flow field plate for the flow field plate to be embedded. The grooves are surrounded by rectangular sealing grooves to ensure the sealing of the electrolyzer. In addition, through holes are punched diagonally in the grooves. These through holes correspond to the water inlet and outlet holes of the flow channel on the anode segmented flow field plate, and there are grooves connecting two adjacent through holes to connect the flow of water and gas in the electrolyzer in series. The positions of these grooves correspond to the runway-type sealing grooves on the sealing cover plate, which ensures the sealing of the electrolyzer. The anode ear on the anode segmented flow field plate is connected to the positive electrode power supply line and the positive electrode feedback line.

[0041] like Figure 2b As shown, the water inlet hole on the flow field separator plate corresponds to the flow channel inlet on the first titanium flow field plate. The reaction water enters the flow channel inlet on the first titanium flow field plate through the water inlet hole, flows through the flow channel, reaches the outlet of the first titanium flow field plate, and then passes through the groove on the flow field separator plate to flow into the flow channel inlet on the second titanium flow field plate. This cycle continues and finally flows to the outlet on the last titanium flow field plate. The outlet on the last titanium flow field plate is opposite to the water (gas) outlet hole on the flow field separator plate. The remaining reaction water and the generated oxygen flow out of the electrolytic cell through this.

[0042] like Figure 3aAs shown in the figure, the five-in-one membrane electrode layer in the proton exchange membrane electrolyzer includes 8 independent membrane electrodes and PET film. The active area of ​​a single membrane electrode is 18×22mm 2 , forming a 4×2 array, the PET film is penetrated along the thickness direction to open a chamber array corresponding to the membrane electrode, and the area of ​​a single diffusion cavity is 23×27mm 2 The membrane electrode is embedded in the chamber, 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 in the figure, 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 ears on each side of the cathode bipolar plate for the negative electrode power supply line to connect. In addition, since the cathode ear area on the cathode bipolar plate is small, a fin is provided in the middle of the upper end surface of the cathode bipolar plate for the negative electrode feedback line to connect, and the current and voltage are measured together with the positive electrode feedback line on the anode ear.

[0045] like Figure 4b As shown, the outer walls of both sides of the cathode bipolar plate are provided with 4 groups 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, so as to monitor and heat the electrode plate temperature, thereby controlling the temperature according to the control requirements of water electrolysis. In addition, two water (gas) outlet holes are provided on the back of the cathode bipolar plate.

[0046] like Figure 5 As shown, the recommended bolt assembly sequence has been marked, which helps to reduce the damage caused by uneven assembly pressure and improve the uniformity of assembly pressure of the electrolytic cell.

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

[0048] When connecting the positive and negative power supply wires, connect the positive power supply wire and the negative power supply wire to the positive ear of the anode segmented flow field plate and the negative ear of the cathode bipolar plate, respectively, so that the voltage passes through the medium at the same distance. In addition, it is recommended to wrap insulation material around the water inlet pipe to reduce the heat loss caused by the heat exchange between the reaction water and the environment.

[0049] like Figure 7As shown, in the power supply circuit, the voltage is supplied by a multi-channel DC power supply through the positive and negative electrode feed lines, and then the positive and negative electrode feed lines summarize the real-time measured voltage and current data into 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 in the electrolytic cell through the thermocouple and heating rod on the cathode bipolar plate, and adjusts its temperature again, so that the temperature in the electrolytic cell falls more accurately near the given value; in the water supply and exhaust system, purer deionized water is used as experimental water. The deionized water passes through a peristaltic pump and enters the electrolytic cell for electrolysis after being heated by the preheater. Finally, the remaining water and generated oxygen after the reaction are discharged through the anode water (gas) outlet on the sealing cover plate, and the electroosmotic water and hydrogen are discharged from the cathode water (gas) outlet on the stainless steel plate. In addition, the digital camera system in front of the electrolytic cell is used to monitor the state of the anode two-phase flow in real time. The lighting lamp provides a strong lighting environment for the camera, and the high-speed camera is used to record the flow pattern of the two-phase flow in the anode flow channel of the electrolytic cell.

[0050] The working process of the anode segmented visualized proton exchange membrane electrolyzer of the present invention is as follows: the reaction water adopts deionized water, passes through a peristaltic pump, is heated to a set temperature by a preheater, enters the anode water supply inlet on the sealing cover plate, and 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 passes through the groove on the flow field partition plate to flow into the inlet on the second titanium flow field plate, and the cycle is repeated until it finally flows to the outlet on the last titanium flow field plate. The outlet on the last titanium flow field plate is opposite to the water (gas) outlet hole on the flow field partition plate and the anode water (gas) outlet on the sealing cover plate, and the remaining reaction water and the generated oxygen flow out of the electrolyzer together. During this process, the eight sub-membrane electrodes on the five-in-one membrane electrode simultaneously perform water electrolysis: the water on the titanium flow field plate passes through the anode diffusion layer to reach the catalyst coating membrane, undergoes an oxidation reaction, generates oxygen and releases hydrogen ions (protons), and the oxygen and unreacted water continue to flow downstream along the flow channel and the groove until they are discharged from the anode water (gas) outlet on the sealing cover. The generated protons pass through the proton exchange membrane, undergo a reduction reaction at the corresponding cathode, generate hydrogen, and flow downward in the flow field of the cathode bipolar plate together with the electroosmotic water, and finally discharge from the cathode water (gas) outlet on the stainless steel plate. During this process, the thermocouple and heating rod on the cathode bipolar plate detect and secondary adjust the temperature of the electrolyzer to ensure the uniformity of the reaction temperature and stabilize the reaction temperature near the given value.

[0051] The above shows and describes 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 above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. An anode segmented visualized proton exchange membrane electrolyzer, comprising an anode terminal plate, a sealing cover plate, a flow field separator 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 terminal plate stacked in sequence; characterized in that: The five-in-one membrane electrode layer is composed of a membrane electrode and a polyethylene terephthalate (PET) film, and the membrane electrode is sequentially composed of an anode diffusion layer, a catalyst coating membrane and a cathode diffusion layer.

2. The anode segmented visualized proton exchange membrane electrolyzer according to claim 1, characterized in that: The flow field separator plate is made of a transparent polycarbonate material, and is engraved with an inward 4×2 groove array corresponding to the anode segmented flow field plate.

3. The anode segmented visualized proton exchange membrane electrolyzer according to claim 2, characterized in that: The groove ring is provided with a rectangular sealing groove, and through holes are punched diagonally in the groove, and the positions of the through holes correspond to the water inlet and outlet holes on the anode separation flow field plate.

4. The anode segmented visualized proton exchange membrane electrolyzer according to claim 3 is characterized in that: The through holes are connected to the through holes on the adjacent grooves by grooves; the positions of the grooves correspond one to one with the racetrack-shaped sealing grooves on the sealing cover plate.

5. The anode segmented visualized proton exchange membrane electrolyzer according to claim 1, characterized in that: The anode segmented flow field plate is composed of 8 independent titanium flow field plates, and the positions correspond one-to-one to the groove array on the anode segmented flow field plate.

6. The anode segmented visualized proton exchange membrane electrolyzer according to claim 5, characterized in that: A flow channel is engraved on the surface of the titanium flow field plate, and an anode pole ear is arranged on the titanium flow field plate; the anode pole ear extends out of the anode segmented proton exchange membrane electrolyzer.

7. The anode segmented visualized proton exchange membrane electrolyzer according to claim 1, characterized in that: The PET film is penetrated along the thickness direction to form a cavity array corresponding to the membrane electrode, and the membrane electrode is embedded in the cavity.

8. The anode segmented visualized proton exchange membrane electrolyzer according to claim 1, characterized in that: A 4×2 channel array corresponding to the position of the membrane electrode is engraved on the front of the cathode bipolar plate, and each channel is surrounded by a rectangular sealing groove; The two sides of the cathode bipolar plate are each provided with four groups of holes symmetrically distributed for inserting thermocouple probes and heating rods; The two side surfaces of the cathode bipolar plate are each provided with four symmetrically distributed cathode pole ears, and a fin is provided in the middle of the upper end surface.

9. The anode segmented visualized proton exchange membrane electrolyzer according to claim 4, characterized in that: The electrolytic cell further comprises an anode gasket and a cathode gasket; the anode gasket and the cathode gasket are both penetrated along the thickness direction to form a diffusion cavity corresponding to the membrane electrode, and the size and position of the diffusion cavity correspond to the membrane electrode.

10. An application method of an electrolytic cell, the electrolytic cell is based on the anode segmented visualized proton exchange membrane electrolytic cell according to any one of claims 1 to 9, characterized in that: Deionized water is used. It passes through a peristaltic pump and is heated to the set temperature by a preheater. It then enters the anode water inlet on the sealing cover plate, and then passes through the through hole on the flow field separator plate to enter the inlet of the first titanium flow field plate. It flows through the flow channel to reach the outlet of the first titanium flow field plate, and then passes through the groove on the flow field separator plate to flow into the through hole 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 is opposite to the anode water (gas) outlet on the sealing cover plate, and the remaining reaction water and the generated oxygen flow out of the electrolyzer from there. In this process, the eight sub-membrane electrodes on the five-in-one membrane electrode simultaneously perform water electrolysis work: the titanium flow The water on the field plate passes through the anode diffusion layer to reach the catalyst coating membrane, undergoes an 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 (gas) outlet on the sealing cover plate; the generated protons pass through the proton exchange membrane, undergo a reduction reaction at the corresponding cathode, generate hydrogen, and flow downward in the flow field of the cathode bipolar plate together with the electroosmotic water, and are finally discharged from the two cathode water (gas) outlets on the stainless steel plate. During this process, the thermocouple and heating rod on the cathode bipolar plate detect and secondary adjust the temperature of the electrolyzer to ensure the uniformity of the reaction temperature and stabilize the reaction temperature near a given value.

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