PEM water electrolysis hydrogen production stamping bipolar plate and PEM electrolytic bath

Abstract

The invention provides a PEM water electrolysis hydrogen production stamping bipolar plate which comprises a plate body, a first water opening is formed in one end of the plate body, and a second water opening is formed in the other end of the plate body; the first water gap and the second water gap are diagonally arranged; a first gap bridge region, a second gap bridge region, a first distribution region, a second distribution region and a first reaction region are arranged on one side surface of the plate body; the first gap bridge area is communicated with the first water gap, and the first distribution area is arranged between the first gap bridge area and the first reaction area; the second gap bridge area is communicated with the second water gap, and the second distribution area is arranged between the second gap bridge area and the first reaction area; each of the first distribution area and the second distribution area comprises a plurality of first bosses and first concave platforms which are alternately arranged. The invention further provides the PEM electrolytic cell. The electrolytic cell has good mechanical strength and conductivity, flow field distribution is uniform, the sealing effect is good, the gas transmission efficiency is improved, and the overall electrolytic efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of batteries, and in particular to a PEM electrolysis water hydrogen production stamping bipolar plate and a PEM electrolyzer. Background Art

[0002] PEM water electrolysis hydrogen production technology uses polymer electrolyte membrane to decompose water into hydrogen and oxygen, with the advantages of high efficiency, compact design and fast response. With the development of renewable energy, this technology is regarded as the key to green hydrogen production. In recent years, through the optimization of materials and systems, the cost has been continuously reduced and the economy has been improved, which has broad application prospects.

[0003] PEM water electrolysis hydrogen production bipolar plates are an important component of proton exchange membrane electrolyzers, used to support current transmission and water electrolysis reactions. They are usually made of titanium alloys or other corrosion-resistant metal materials with good conductivity and mechanical strength. The design of metal bipolar plates must take into account catalytic activity, corrosion resistance and weight reduction to improve the overall efficiency and durability of the system. At present, existing technologies optimize the structure and coating of bipolar plates to reduce their cost and improve electrolysis performance. Stamping bipolar plates is one of the important development directions.

[0004] PEM water electrolysis for hydrogen production needs to operate under high pressure, which places higher requirements on the mechanical strength and sealing effect of stamped bipolar plates. Although the existing technology has completed the preparation of 0.5mm thick stamped bipolar plates, which reduces the cost of raw materials and is lighter in weight, the active area is not large. Moreover, the manufacture of large-scale water electrolysis hydrogen production stamped bipolar plates relies on large-scale stamping equipment, which is costly, and this is one of the factors restricting the development of stamped bipolar plates. On the other hand, the single plate of the stamped bipolar plate needs to be designed with a reasonable structure, and a comprehensive analysis of the plate strength, fluid dynamics and electrochemical performance is carried out; for the design of the one-plate two-field plate, it is also necessary to take into account the forming process of the stamped bipolar plate and the complex high-pressure sealing structure design, which makes the existing stamped bipolar plates have problems such as insufficient mechanical strength, uneven flow field distribution, poor sealing effect and low electrolysis efficiency. Summary of the invention

[0005] Based on this, the present invention provides a PEM water electrolysis hydrogen production stamping bipolar plate and a PEM electrolyzer, aiming to solve the problems existing in the prior art such as insufficient mechanical strength of the stamping bipolar plate, uneven flow field distribution, poor sealing effect, and low electrolysis efficiency.

[0006] To achieve the above-mentioned purpose, on the one hand, the embodiment of the present invention proposes the following technical solution: a PEM water electrolysis hydrogen production stamping bipolar plate, comprising a plate body, one end of the plate body is provided with a first water inlet, and the other end is provided with a second water inlet; the first water inlet and the second water inlet are arranged diagonally; A first bridge area, a second bridge area, a first distribution area, a second distribution area and a first reaction area are arranged on one side of the plate body; the first bridge area is connected to the first water outlet, and the first distribution area is arranged between the first bridge area and the first reaction area; the second bridge area is connected to the second water outlet, and the second distribution area is arranged between the second bridge area and the first reaction area; The first distribution area and the second distribution area both include a plurality of first convex platforms and first concave platforms that are alternately arranged.

[0007] As a preferred embodiment, several first bosses and first recesses are arranged in a row from the first distribution area to the second distribution area; in the same row, the first bosses and the first recesses are arranged alternately, and the first bosses and the first recesses are arranged at equal intervals.

[0008] As a preferred embodiment, a plurality of the first bosses and the first recesses are arranged in a row from one side of the plate to the other side; in the same row, the first bosses and the first recesses are arranged alternately, and the first bosses and the first recesses are arranged at equal intervals.

[0009] As a preferred embodiment, the first boss has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the distance between adjacent first bosses and first recesses is from half of the first boss to one of the first bosses.

[0010] As a preferred embodiment, the first boss is a circular boss, and the first recess is a circular recess; the height of the first boss is equal to the depth of the first recess, and the width of the first boss is equal to the width of the first recess.

[0011] As a preferred embodiment, the first bridge area and the second bridge area both include a plurality of first protrusions arranged in parallel with each other; the plurality of first protrusions are arranged at equal intervals; and a first groove is arranged between two adjacent first protrusions.

[0012] As a preferred embodiment, the first protrusion has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the width ratio of the first groove to the first protrusion is 1:2 to 2:1.

[0013] As a preferred embodiment, the first reaction zone includes first S-shaped protrusions and first S-shaped grooves that are alternately arranged; the first S-shaped protrusions and the first S-shaped grooves are arranged at equal intervals.

[0014] As a preferred embodiment, the first S-shaped protrusion has a stamping draft angle; the stamping draft angle ranges from 25° to 45°; the width ratio of the first S-shaped groove to the first S-shaped protrusion is 1:2 to 2:1; the angle of the first S-shaped groove is 15° to 30°.

[0015] As a preferred embodiment, a first sealing groove is arranged circumferentially on the edge of one side surface; the first bridge area, the second bridge area, the first distribution area, the second distribution area and the first reaction area are all arranged on the inner side of the first sealing groove; a first sealing strip is laid in the first sealing groove, and the first water outlet and the second water outlet are both laid with the first sealing strip on their outer peripheries.

[0016] As a preferred embodiment, the first water inlet is a water inlet, and the second water inlet is a water outlet; or, the first water inlet is a water outlet, and the second water inlet is a water inlet.

[0017] As a preferred embodiment, a first hydrogen outlet adjacent to the first water inlet is provided at one end of the plate body, and a second hydrogen outlet adjacent to the second water inlet is provided at the other end; the first hydrogen outlet and the second hydrogen outlet are arranged diagonally.

[0018] As a preferred embodiment, a third bridge area, a fourth bridge area, a third distribution area, a fourth distribution area and a second reaction area are arranged on the other side of the plate body; the third bridge area is connected to the first hydrogen outlet, and the third distribution area is arranged between the third bridge area and the second reaction area; the fourth bridge area is connected to the second hydrogen outlet, and the fourth distribution area is arranged between the fourth bridge area and the second reaction area; The third distribution area and the fourth distribution area both include a plurality of second convex platforms and second concave platforms that are alternately arranged; the second convex platforms are overlapped with the first concave platforms, and the second concave platforms are overlapped with the first convex platforms.

[0019] As a preferred embodiment, the third bridge area is disposed adjacent to the back side of the first bridge area; the fourth bridge area is disposed adjacent to the back side of the second bridge area; The third bridge area and the fourth bridge area both include a plurality of second protrusions arranged in parallel with each other; a plurality of the second protrusions are arranged at equal intervals; and a second groove is arranged between two adjacent second protrusions.

[0020] As a preferred embodiment, the second reaction zone includes second S-shaped protrusions and second S-shaped grooves that are alternately arranged; the second S-shaped protrusions and the second S-shaped grooves are arranged at equal intervals.

[0021] As a preferred embodiment, a second sealing groove is circumferentially arranged on the edge of the other side surface; the third bridge area, the fourth bridge area, the third distribution area, the fourth distribution area and the second reaction area are all arranged on the inner side of the second sealing groove; a second sealing strip is laid in the second sealing groove, and the second sealing strip is laid on the outer periphery of the first hydrogen outlet and the second hydrogen outlet.

[0022] As a preferred embodiment, the plate body is a plate body made of one or at least two of pure titanium, titanium alloy and nickel-based alloy, preferably a titanium alloy plate body or a nickel-based alloy plate body.

[0023] As a preferred embodiment, the titanium alloy plate contains the following components by mass percentage: 90% titanium, 6% aluminum and 4% vanadium; The nickel-based alloy plate contains the following components in percentage by mass: ≥58% nickel, 20%-25% chromium, 8%-12% molybdenum and 3%-5% niobium.

[0024] On the other hand, an embodiment of the present invention further provides a PEM electrolyzer, wherein the PEM electrolyzer comprises the PEM water electrolysis hydrogen production stamping bipolar plate.

[0025] As a preferred embodiment, the PEM electrolyzer includes several PEM water electrolysis hydrogen production stamping bipolar plates and several membrane electrodes arranged in a stacked manner, and the PEM water electrolysis hydrogen production stamping bipolar plates and the membrane electrodes are arranged alternately; two adjacent PEM water electrolysis hydrogen production stamping bipolar plates are assembled in a rotating manner, and after assembling one of the PEM water electrolysis hydrogen production stamping bipolar plates, it is necessary to rotate 180 degrees around the normal central axis before assembling the other PEM water electrolysis hydrogen production stamping bipolar plate.

[0026] Beneficial effects achieved by the present invention: The PEM water electrolysis hydrogen production stamping bipolar plate of the present application has good mechanical strength, corrosion resistance and electrical conductivity, its flow field distribution is uniform, the sealing effect is good, it can effectively improve the gas transmission efficiency, can effectively reduce resistance damage, thereby effectively improving the overall electrolysis efficiency, and can solve the problems of insufficient mechanical strength, uneven flow field distribution, poor sealing effect, low electrolysis efficiency, etc. The electrolyzer made by the PEM water electrolysis hydrogen production stamping bipolar plate of the present application can maintain good sealing, can effectively prevent gas leakage, has strong adaptability and high electrolysis efficiency. The present application has a simple structure, is easy to disassemble and assemble, is easy to maintain, has good stability, is economical, safe and practical, and can well meet the needs of actual use. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0028] Figure 1 A schematic structural diagram of one side (anode side) of a stamped bipolar plate for producing hydrogen by electrolysis of water using PEM according to an embodiment of the present invention; Figure 2 for Figure 1 Schematic diagram of the sealing structure of one side (anode side) of the PEM water electrolysis hydrogen production stamping bipolar plate; Figure 3 for Figure 1 A schematic diagram of the structure of the other side (cathode side) of the PEM water electrolysis hydrogen production stamping bipolar plate; Figure 4 for Figure 3 Schematic diagram of the sealing structure of the other side (cathode side) of the PEM water electrolysis hydrogen production stamping bipolar plate; Figure 5 A schematic diagram of a plate stacking structure of a PEM electrolyzer in a rotating assembly according to another embodiment of the present invention; Figure 6 To adopt Figure 5 Schematic diagram of the performance curve of the PEM electrolyzer for water electrolysis performance test (water temperature 80°C, equipped with 12 membrane electrodes); Figure 7 for Figure 5 Schematic diagram of the dynamic loading performance curve of each membrane electrode reaction (12 pieces in total) of the PEM electrolyzer.

[0029] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0034] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] The punched bipolar plate for hydrogen production by water electrolysis in this application has the following advantages: (1) Cost-effectiveness: The electrolytic water hydrogen production stamping bipolar plate of the present application can be mass-produced, reducing production costs and making the electrolytic water technology more economical.

[0036] (2) High production efficiency: The electrolytic water hydrogen production stamping bipolar plate of the present application can be produced quickly and efficiently, with uniform specifications, stable quality and high production efficiency.

[0037] (3) High precision: The electrolysis of water to produce hydrogen stamped bipolar plates of the present application has high precision, which can ensure the quality and stability of the product.

[0038] (4) Flexible design: The electrolytic water hydrogen production stamping bipolar plate of the present application can be designed with different shapes and sizes according to the needs to meet the needs of different application scenarios.

[0039] Specifically, Figures 1 to 4 As shown, on the one hand, the embodiment of the present invention proposes the following technical solution: a PEM water electrolysis hydrogen production stamping bipolar plate, comprising a plate body 10, one end of the plate body 10 is provided with a first water inlet 11, and the other end is provided with a second water inlet 12; the first water inlet 11 and the second water inlet 12 are arranged diagonally; A first bridge area A, a second bridge area B, a first distribution area C, a second distribution area D and a first reaction area E are arranged on one side surface (anode surface, i.e., water flow transmission surface) of the plate body 10; the first bridge area A is connected to the first water port 11, and the first distribution area C is arranged between the first bridge area A and the first reaction area E; the second bridge area B is connected to the second water port 12, and the second distribution area D is arranged between the second bridge area B and the first reaction area E; The first distribution area C and the second distribution area D both include a plurality of first convex platforms 13 and first concave platforms 14 that are alternately arranged.

[0040] As a preferred embodiment, several first bosses 13 and first recesses 14 are arranged in a row from the first distribution area C to the second distribution area D; in the same row, the first bosses 13 and the first recesses 14 are arranged alternately, and the first bosses 13 and the first recesses 14 are arranged at equal intervals.

[0041] As a preferred embodiment, several first bosses 13 and first recesses 14 are arranged in a row from one side to the other side of the plate body 10; in the same row, the first bosses 13 and the first recesses 14 are arranged alternately, and the first bosses 13 and the first recesses 14 are arranged at equal intervals.

[0042] As a preferred embodiment, the first boss 13 has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the distance between adjacent first bosses 13 and first recesses 14 is from half of the first boss to one of the first bosses.

[0043] As a preferred embodiment, the first boss 13 is a circular boss, and the first recess 14 is a circular recess; the height of the first boss 13 is equal to the depth of the first recess 14 , and the width of the first boss 13 is the same as the width of the first recess 14 .

[0044] In the present application, the first distribution area and the second distribution area are both structures in which raised and recessed cones are alternately distributed, forming a water flow distribution channel, which can effectively improve the uniformity of water vapor distribution and transmission efficiency.

[0045] As a preferred embodiment, the first bridge area A and the second bridge area B both include a plurality of first protrusions 15 arranged in parallel with each other; the plurality of first protrusions 15 are arranged at equal intervals; and a first groove 16 is arranged between two adjacent first protrusions 15. In the present application, the bridge area is composed of at least two first protrusions to form a water flow channel.

[0046] As a preferred embodiment, the first protrusion 15 has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the width ratio of the first groove 16 to the first protrusion 15 is 1:2 to 2:1.

[0047] As a preferred embodiment, the first reaction zone E includes first S-shaped protrusions 17 and first S-shaped grooves 18 that are alternately arranged; the first S-shaped protrusions 17 and the first S-shaped grooves 18 are arranged at equal intervals.

[0048] As a preferred embodiment, the first S-shaped protrusion 17 has a stamping draft angle; the stamping draft angle ranges from 25° to 45°; the width ratio of the first S-shaped groove 18 to the first S-shaped protrusion 17 is 1:2 to 2:1; the angle of the first S-shaped groove 18 is 15° to 30°.

[0049] The first reaction zone is a structure in which raised and recessed first S-shaped protrusions and first S-shaped grooves are alternately distributed, forming a stable water flow transmission channel. The water flow rate is uniform and the pressure distribution is uniform, which can effectively promote the stable operation of the electrolysis reaction.

[0050] As a preferred embodiment, a first sealing groove 19 is circumferentially arranged on the edge of one side surface; the first bridge area A, the second bridge area B, the first distribution area C, the second distribution area D and the first reaction area E are all arranged on the inner side of the first sealing groove 19; a first sealing strip 20 is laid in the first sealing groove 19, and the first water outlet 11 and the second water outlet 12 are both peripheries thereof are laid with the first sealing strip 20.

[0051] As a preferred embodiment, the first water inlet 11 is a water inlet, and the second water inlet 12 is a water outlet; or, the first water inlet 11 is a water outlet, and the second water inlet 12 is a water inlet.

[0052] As a preferred embodiment, the plate body 10 is provided with a first hydrogen outlet 21 adjacent to the first water inlet 11 at one end, and a second hydrogen outlet 22 adjacent to the second water inlet 12 at the other end; the first hydrogen outlet 21 and the second hydrogen outlet 22 are arranged diagonally.

[0053] The thickness of the PEM electrolysis water hydrogen production stamping bipolar plate of the present application is ≤0.5mm, and it has good strength and rigidity. Its first water inlet and second water inlet are both set as two large openings, and the first hydrogen outlet and the second hydrogen outlet are both set as two small openings, so that the size of the water inlet and outlet is larger than that of the hydrogen outlet, which is more conducive to the transmission of water.

[0054] As a preferred embodiment, the other side surface (cathode surface, i.e., hydrogen transmission surface) of the plate body 10 is provided with a third bridge area F, a fourth bridge area G, a third distribution area H, a fourth distribution area I, and a second reaction area J; the third bridge area F is connected to the first hydrogen outlet 21, and the third distribution area H is arranged between the third bridge area F and the second reaction area J; the fourth bridge area G is connected to the second hydrogen outlet 22, and the fourth distribution area I is arranged between the fourth bridge area G and the second reaction area J; The third distribution area H and the fourth distribution area I both include a plurality of alternately arranged second bosses 23 and second recesses 24 ; the second bosses 23 are overlapped with the first recesses 14 , and the second recesses 24 are overlapped with the first bosses 13 .

[0055] In the embodiment of the present application, the overlapping arrangement means that at the same position of the plate body, the concave platform on one side overlaps with the convex platform on the other side, or the convex platform on one side overlaps with the concave platform on the other side.

[0056] As a preferred embodiment, the third bridge area F (convex structure) is disposed adjacent to the back side (concave structure) of the first bridge area A; the fourth bridge area G (convex structure) is disposed adjacent to the back side (concave structure) of the second bridge area B; The third bridge area F and the fourth bridge area G both include a plurality of second protrusions 25 arranged in parallel with each other; a plurality of the second protrusions 25 are arranged at equal intervals; and a second groove 26 is arranged between two adjacent second protrusions 25 .

[0057] As a preferred embodiment, the second reaction zone J includes second S-shaped protrusions 27 and second S-shaped grooves 28 that are alternately arranged; the second S-shaped protrusions 27 and the second S-shaped grooves 28 are arranged at equal intervals.

[0058] Due to the forming characteristics of the stamped bipolar plate, the bridge area structure at the hydrogen outlet is a convex structure to form a hydrogen flow channel. Similarly, the number of convex structures at the hydrogen outlet is at least two; similarly, the cathode surface distribution area is also a structure with convex and concave truncated cones alternately distributed to form a hydrogen distribution channel. The reaction area is a structure with convex and concave second S-shaped convexities and second S-shaped grooves alternately distributed to form a stable hydrogen transmission channel.

[0059] In the present application, by providing a structure with alternating protrusions and depressions, a fluid cavity can be formed on both sides of the anode and cathode of the single-piece electrode plate, thereby facilitating the circulation of reaction water and hydrogen.

[0060] As a preferred embodiment, a second sealing groove 29 is circumferentially arranged on the edge of the other side surface; the third bridge area F, the fourth bridge area G, the third distribution area H, the fourth distribution area I and the second reaction area J are all arranged on the inner side of the second sealing groove 29; a second sealing strip 30 is laid in the second sealing groove 29, and the second sealing strip 30 is laid on the outer periphery of the first hydrogen outlet 21 and the second hydrogen outlet 22.

[0061] The higher anode potential, large amount of liquid water pressure, greater assembly force and other conditions of the PEM electrolyzer pose greater challenges to its sealing method. The structure of the present application can achieve a stable sealing effect with the cooperation of the first sealing strip (anode sealing strip) and the second sealing strip (cathode sealing strip). The types of strips used mainly include silicone rubber, fluororubber, EPDM rubber, polytetrafluoroethylene and corresponding modified gaskets. In the assembly mode of the present application, when the stacking force reaches the design value, the flow channel ridge of the plate is in full contact with the membrane electrode, and the top surface of the raised structure in the bridge area is in the same plane as the top surface of the sealing strip after compression, thus forming a stable sealing effect under the multi-layer stacking structure. Under high-pressure working conditions, a stable support can also be formed between the plate and the membrane electrode, so that the entire electrolysis reaction can be carried out continuously and efficiently.

[0062] As a preferred embodiment, the plate body 10 is a plate body made of one or at least two of pure titanium, titanium alloy and nickel-based alloy, preferably a titanium alloy plate body or a nickel-based alloy plate body.

[0063] As a preferred embodiment, the titanium alloy plate contains the following components by mass percentage: 90% titanium, 6% aluminum and 4% vanadium; The nickel-based alloy plate contains the following components in percentage by mass: ≥58% nickel, 20%-25% chromium, 8%-12% molybdenum and 3%-5% niobium.

[0064] The plate of the present application has good corrosion resistance and can ensure stable operation during the electrolysis process. In the titanium alloy plate, titanium accounts for 90%, which can provide basic corrosion resistance and processing performance; aluminum content accounts for 6%, which can improve the strength and thermal stability of the alloy, and can also form an aluminum oxide protective film to enhance corrosion resistance; vanadium content is 4%, which can improve the plasticity and processing performance of the plate, refine the grains, and improve strength and toughness.

[0065] In the nickel-based alloy plate, the nickel content is more than 58%, which has good corrosion resistance and high temperature stability; the chromium content is 20% to 25%, which can form a dense chromium oxide protective film on the alloy surface and enhance the corrosion resistance of the alloy in oxidizing media; the molybdenum content is 8% to 12%, which can improve the corrosion resistance of the alloy in reducing media and enhance the ability to resist pitting and crevice corrosion; the niobium content is 3% to 5%, which can form stable carbides with carbon, reduce the tendency of intergranular corrosion, and improve the strength and toughness of the alloy.

[0066] Before preparing the PEM water electrolysis hydrogen production stamping bipolar plate of this application, the raw material plate needs to be surface treated to remove the surface oxide layer, oil and other impurities to ensure the quality of the subsequent molding process. The stamping process of the PEM water electrolysis hydrogen production stamping bipolar plate is as follows: ① Cutting: Cut the treated plate according to the required size to obtain a blank of suitable size; ② Stamping: Put the blank into the stamping die, apply pressure through the press to make the plate plastically deformed, so as to obtain the required shape. Preferably, the thickness of the stamped bipolar plate of this application is larger than that of the fuel cell plate, and the tonnage of the press needs to be more than 1,000 tons. During the stamping process, it is necessary to control the parameters such as the stamping speed, pressure size and closing height of the mold to ensure the molding quality of the stamped plate. It is necessary to perform at least one pre-pressing molding process and finally perform the final molding. ③ After stamping, complete the punching, edge punching and other processes, remove the excess scraps, so that the size meets the design requirements. This process includes but is not limited to die punching and laser cutting.

[0067] Before assembling into an electrolytic cell, the plate needs to be heat treated to eliminate internal stress and improve the plasticity and toughness of the material. Common heat treatment processes include annealing, which heats the stamped plate to a certain temperature, keeps it warm for a period of time, and then slowly cools it. Then, a coating treatment is performed to improve the corrosion resistance and conductivity of the stamped plate. Usually, a catalytically active coating is applied to its surface to reduce the overpotential during the electrolysis process and improve the electrolysis efficiency.

[0068] On the other hand, Figure 5 As shown, an embodiment of the present invention further provides a PEM electrolyzer, and the PEM electrolyzer includes the PEM water electrolysis hydrogen production stamping bipolar plate 100.

[0069] As a preferred embodiment, the PEM electrolyzer includes several PEM water electrolysis hydrogen production stamping bipolar plates 100 and several membrane electrodes 200 arranged in a stacked manner, and the PEM water electrolysis hydrogen production stamping bipolar plates 100 and the membrane electrodes 200 are alternately arranged; two adjacent PEM water electrolysis hydrogen production stamping bipolar plates 100 are assembled in a rotating manner. After assembling one of the PEM water electrolysis hydrogen production stamping bipolar plates 100, it is necessary to rotate 180 degrees around the normal central axis before assembling the other PEM water electrolysis hydrogen production stamping bipolar plate 100.

[0070] The rotational assembly method can ensure stable support between the plates and membrane electrode and other components during the assembly of the electrolyzer, that is, after assembling a bipolar plate and a membrane electrode in sequence, the next bipolar plate needs to be rotated 180 degrees around the normal center axis (that is, the normal center axis of the previous bipolar plate) before assembly. In this way, the raised truncated cone structure top surface of the anode distribution area of ​​the first PEM electrolysis hydrogen production stamping bipolar plate can stably contact the raised truncated cone structure top surface of the cathode distribution area of ​​the next PEM electrolysis hydrogen production stamping bipolar plate. At the same time, Figure 5 As shown, the S-shaped flow channel of the reaction zone of the first PEM electrolysis hydrogen production stamping bipolar plate is cross-distributed with the S-shaped flow channel of the reaction zone of the next PEM electrolysis hydrogen production stamping bipolar plate, forming a stable and reliable electrical contact on each small section of the flow channel, reducing resistance loss, thereby improving the overall electrolysis efficiency. In this assembly mode, the structural strength of the PEM electrolysis hydrogen production stamping bipolar plate is guaranteed, and the mechanical strength of the entire electrolyzer is higher and the stability is better.

[0071] exist Figure 5 The performance of the PEM electrolyzer was tested under the plate stacking structure shown in the figure. Pure water was introduced into the electrolyzer through the water inlet manifold, and current was applied to the positive and negative electrodes to promote the electrolysis of water. Hydrogen was collected at the hydrogen manifold. During the experiment, the performance parameters of the electrolyzer were recorded by setting conditions such as water flow rate and water temperature. Figure 6 The performance curve of 12 membrane electrodes is shown when the water temperature is 80℃. Figure 6 It can be seen that as the current density increases from 0.1A / cm 2 Load to 2A / cm 2 , each level increases by 0.1A / cm 2 , at 1A / cm 2 At the current density, the voltage is 1.58V; at 2A / cm 2 At this current density, the voltage is 1.69V. Figure 7 The dynamic loading performance curve of each membrane electrode reaction (a total of 12 membranes) shows that as the current density increases from 0.1A / cm 2 Load to 2A / cm 2 , each level increases by 0.1A / cm2 , the voltage responds quickly to changes, tends to be stable in a short time, and has strong adaptability. As shown in Table 1, at 1A / cm 2 At the current density, the total voltage is 18.93V, the average value of a single chip is 1.5775V, the minimum value is 1.57V, the maximum value is 1.58V, and the range is about 10mV; at 2A / cm 2 Under the current density, the total voltage is 20.27V, the single chip average is 1.6892V, the minimum value is 1.68V, the maximum value is 1.69V, the range is about 10mV, the performance difference between each reaction is small, and the stability is good.

[0072] Table 1 Summary of performance test results of 12 membrane electrodes type Total voltage / V Single chip average value / V Standard Deviation Min. value / V Maximum value / V Range / V 1.0 Electricity density 18.93 1.5775 0.00143 1.57 1.58 0.01 2.0 Electricity density 20.27 1.6892 0.00281 1.68 1.69 0.01 The PEM water electrolysis hydrogen production stamping bipolar plate of the present application has good mechanical strength, corrosion resistance and electrical conductivity, and its flow field distribution is uniform, the sealing effect is good, and it can effectively improve the gas transmission efficiency, and can effectively reduce resistance damage, thereby effectively improving the overall electrolysis efficiency, and can solve the problems of insufficient mechanical strength, uneven flow field distribution, poor sealing effect, and low electrolysis efficiency. The electrolyzer made by the PEM water electrolysis hydrogen production stamping bipolar plate of the present application can maintain good sealing, can effectively prevent gas leakage, has strong adaptability, and high electrolysis efficiency. The structure of the present application is simple, easy to disassemble and assemble, easy to maintain, has good stability, is economical, safe and practical, and can well meet the needs of actual use.

[0073] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0074] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0075] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A PEM water electrolysis hydrogen production stamping bipolar plate, characterized in that: It comprises a plate body, one end of which is provided with a first water inlet, and the other end of which is provided with a second water inlet; the first water inlet and the second water inlet are arranged diagonally; A first bridge area, a second bridge area, a first distribution area, a second distribution area and a first reaction area are arranged on one side of the plate body; the first bridge area is connected to the first water outlet, and the first distribution area is arranged between the first bridge area and the first reaction area; the second bridge area is connected to the second water outlet, and the second distribution area is arranged between the second bridge area and the first reaction area; The first distribution area and the second distribution area both include a plurality of first convex platforms and first concave platforms that are alternately arranged.

2. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: In the direction from the first distribution area to the second distribution area, a plurality of the first projections and the first recesses are arranged in a row; in the same row, the first projections and the first recesses are arranged alternately, and the first projections and the first recesses are arranged at equal intervals.

3. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: In a direction from one side to the other side of the plate body, a plurality of the first bosses and the first recesses are arranged in a row; in the same row, the first bosses and the first recesses are arranged alternately, and the first bosses and the first recesses are arranged at equal intervals.

4. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: The first boss has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the distance between adjacent first bosses and first recesses is from half of the first boss to one of the first bosses.

5. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: The first bridge area and the second bridge area both include a plurality of first protrusions arranged in parallel with each other; the plurality of first protrusions are arranged at equal intervals; and a first groove is arranged between two adjacent first protrusions; The first protrusion has a stamping draft angle, and the stamping draft angle ranges from 25° to 45°; the width ratio of the first groove to the first protrusion is 1:2 to 2:

1.

6. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: The first reaction zone comprises first S-shaped protrusions and first S-shaped grooves arranged alternately; the first S-shaped protrusions and the first S-shaped grooves are arranged at equal intervals; The first S-shaped protrusion has a stamping draft angle; the stamping draft angle ranges from 25° to 45°; the width ratio of the first S-shaped groove to the first S-shaped protrusion is 1:2 to 2:1; the angle of the first S-shaped groove is 15° to 30°.

7. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: A first sealing groove is arranged circumferentially on the edge of the one side surface; the first bridge area, the second bridge area, the first distribution area, the second distribution area and the first reaction area are all arranged on the inner side of the first sealing groove; a first sealing strip is laid in the first sealing groove, and the first nozzle and the second nozzle are both circumferentially laid with the first sealing strip; The first water inlet is a water inlet, and the second water inlet is a water outlet; or, the first water inlet is a water outlet, and the second water inlet is a water inlet.

8. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: One end of the plate body is provided with a first hydrogen outlet adjacent to the first water inlet, and the other end is provided with a second hydrogen outlet adjacent to the second water inlet; the first hydrogen outlet and the second hydrogen outlet are arranged diagonally; The other side of the plate body is provided with a third bridge area, a fourth bridge area, a third distribution area, a fourth distribution area and a second reaction area; the third bridge area is connected to the first hydrogen outlet, and the third distribution area is arranged between the third bridge area and the second reaction area; the fourth bridge area is connected to the second hydrogen outlet, and the fourth distribution area is arranged between the fourth bridge area and the second reaction area; The third distribution area and the fourth distribution area both include a plurality of second convex platforms and second concave platforms that are alternately arranged; the second convex platforms are overlapped with the first concave platforms, and the second concave platforms are overlapped with the first convex platforms.

9. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 8, characterized in that: The third bridge area is disposed adjacent to the back side of the first bridge area; the fourth bridge area is disposed adjacent to the back side of the second bridge area; The third bridge area and the fourth bridge area both include a plurality of second protrusions arranged in parallel with each other; the plurality of second protrusions are arranged at equal intervals; and a second groove is arranged between two adjacent second protrusions; The second reaction zone comprises second S-shaped protrusions and second S-shaped grooves arranged alternately; the second S-shaped protrusions and the second S-shaped grooves are arranged at equal intervals; A second sealing groove is circumferentially arranged on the edge of the other side surface; the third bridge area, the fourth bridge area, the third distribution area, the fourth distribution area and the second reaction area are all arranged on the inner side of the second sealing groove; a second sealing strip is laid in the second sealing groove, and the second sealing strip is laid on the outer periphery of the first hydrogen outlet and the second hydrogen outlet.

10. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 1, characterized in that: The plate body is made of one or at least two of pure titanium, titanium alloy and nickel-based alloy.

11. The PEM water electrolysis hydrogen production stamping bipolar plate according to claim 10, characterized in that: The plate body is a titanium alloy plate body or a nickel-based alloy plate body; The titanium alloy plate contains the following components by mass percentage: 90% titanium, 6% aluminum and 4% vanadium; The nickel-based alloy plate contains the following components in percentage by mass: ≥58% nickel, 20%-25% chromium, 8%-12% molybdenum and 3%-5% niobium.

12. A PEM electrolyzer, characterized in that: The PEM electrolyzer comprises the PEM water electrolysis hydrogen production stamped bipolar plate according to any one of claims 1 to 11.

13. The PEM electrolyzer according to claim 12, characterized in that: The PEM electrolyzer comprises a plurality of PEM water electrolysis hydrogen production stamping bipolar plates and a plurality of membrane electrodes which are arranged in a stacked manner, wherein the PEM water electrolysis hydrogen production stamping bipolar plates and the membrane electrodes are arranged alternately; two adjacent PEM water electrolysis hydrogen production stamping bipolar plates are assembled in a rotating manner, and after assembling one of the PEM water electrolysis hydrogen production stamping bipolar plates, it is necessary to rotate 180 degrees around the normal central axis before assembling the other PEM water electrolysis hydrogen production stamping bipolar plate.

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