An endless frame type AEM electrolytic cell

Abstract

The utility model provides a kind of endless frame type AEM electrolytic cell, including the upper end plate, upper insulating plate, upper current collector plate, anode single pole plate, membrane electrode, cathode single pole plate, lower current collector plate, lower insulating plate and lower end plate that are sequentially arranged and docked, the upper current collector plate and the lower current collector plate are connected with the positive and negative poles of power supply respectively, the anode single pole plate has line surface sealing structure between the membrane electrode, the cathode single pole plate has line surface sealing structure between the membrane electrode, the anode single pole plate and the cathode single pole plate have flow channel for lye, water, gas circulation.The endless frame type AEM electrolytic cell removes pole frame structure, simultaneously sets up the sealing structure of line surface sealing form between pole plate and membrane electrode, can effectively reduce the cost of production and assembly pole frame, can also improve the performance of AEM electrolytic cell by reducing pole distance, can also reduce the difficulty of disassembly maintenance.

Description

Technical Field

[0001] This utility model relates to the technical field of water electrolysis hydrogen production stacks, and more precisely to a frameless AEM electrolyzer. Background Technology

[0002] Hydrogen energy is a pollution-free and high-energy-density new energy source. Hydrogen gas is also zero-pollution during use, producing no carbon dioxide. Hydrogen energy storage, as a novel energy storage method, boasts advantages such as long discharge time, large capacity, high economic efficiency, flexible storage and transportation, and environmental friendliness. Anion exchange membrane (AEM) electrolyzers, as an emerging water electrolysis hydrogen production technology, combine the advantages of traditional alkaline electrolyzers and proton exchange membrane (PEM) electrolyzers. They can use non-precious metal catalysts to reduce material costs and feature a compact structure, high efficiency, and adaptability to fluctuating input. Furthermore, with the continuous advancement of AEM electrolyzer technologies, it is expected to become one of the important technological routes for low-cost, high-performance, and green hydrogen production.

[0003] The working principle of AEM electrolytic cell is as follows: Figure 1 As shown, a DC voltage is applied to the anode and cathode of the AEM electrolyzer. Water permeates from the anode through the AEM to the cathode, where it receives electrons under the action of the cathode catalyst and undergoes the hydrogen evolution reaction (4H₂O + 4e⁻). - →4OH - The hydrogen evolution reaction (+2H2) produces hydrogen gas, which is released through the gas diffusion layer (GDL). The hydroxide ions (OH-) produced by the hydrogen evolution reaction pass through the anode (AEM) and return to the anode. Under the action of the anode catalyst, the OH- ions undergo the oxygen evolution reaction (4OH-) (4OH-). - →2H₂O + O₂ + 4e - Oxygen is produced, and it flows through the gas diffusion layer and is released along with the electrolyte.

[0004] Traditional AEM electrolyzers, to ensure sealing performance, often employ a frame-based design, consisting of end plates, insulating plates, current collectors, anode single-electrode plates, anode frame, anode gas diffusion layer, membrane electrode, cathode gas diffusion layer, cathode frame, cathode single-electrode plate, current collector, insulating plates, and end plates. The frame increases the distance between the anode and cathode single-electrode plates (electrode spacing), increasing resistance and reducing the performance of the AEM electrolyzer. The frame-based design not only increases the size and weight of the electrolyzer but also significantly increases manufacturing costs and maintenance / disassembly difficulty due to its complex processing and assembly requirements. Furthermore, to ensure resistance to high temperatures and chemical corrosion, the frame is generally made of high-performance specialty engineering plastics, such as polyphenylene sulfone (PPSU) or polysulfone (PSU).

[0005] It is evident that the price of the electrode frame material is very high, and the manufacture of the electrode frame requires mold making, resulting in the electrode frame cost accounting for 15%-20% of the overall cost of the AEM electrolyzer, thus increasing the overall cost. Furthermore, the electrode frame is prone to plastic deformation under high pressure, which can severely compromise its sealing performance. The electrode frame structure also increases the assembly difficulty of the AEM electrolyzer. Existing technologies also include AEM electrolyzer designs that eliminate the electrode frame, but these exhibit poor sealing performance and pose a high risk of leakage.

[0006] In summary, there is a need in the art for AEM electrolyzer designs that allow for the removal of the electrode frame while ensuring a tight seal, in order to reduce costs, decrease electrode spacing, improve performance, and simplify disassembly and maintenance without increasing the risk of leakage. Utility Model Content

[0007] In view of this, the purpose of this utility model is to provide a frameless AEM electrolytic cell, which eliminates the frame structure and sets a line-to-surface sealing structure between the electrode plate and the membrane electrode, so as to reduce costs, improve performance, and reduce the difficulty of disassembly and maintenance while ensuring sealing performance.

[0008] To achieve the above objectives, this utility model provides a frameless AEM electrolytic cell, comprising an upper end plate, an upper insulating plate, an upper current collector, an anode monopole plate, a membrane electrode, a cathode monopole plate, a lower current collector plate, a lower insulating plate, and a lower end plate arranged and connected in sequence. The upper current collector plate and the lower current collector plate are respectively connected to the positive and negative terminals of a power supply. The anode monopole plate and the membrane electrode have a line-to-surface sealing structure, and the cathode monopole plate and the membrane electrode have a line-to-surface sealing structure. The anode monopole plate and the cathode monopole plate have flow channels for the flow of alkali solution, water, and gas.

[0009] Preferably, the membrane electrode includes an anion exchange membrane and an encapsulation layer outside the anion exchange membrane.

[0010] Preferably, the anode monopole plate is connected to the encapsulation layer through a line-to-surface sealing structure, and the cathode monopole plate is connected to the encapsulation layer through a line-to-surface sealing structure.

[0011] Preferably, the encapsulation layer is a PEN film or a PPS film.

[0012] Preferably, the linear sealing structure is a sealing water ripple line located on the surface of the anode monopole plate and the cathode monopole plate.

[0013] Preferably, the raised height of the sealing water ripple line is 0.2 mm.

[0014] Preferably, the linear sealing structure is a sealing groove located on the surface of the anode monopole plate and the cathode monopole plate, and the sealing groove is filled with sealant or fitted with a sealing ring.

[0015] Preferably, an upper sealing gasket is provided between the anode monopolar plate and the membrane electrode, and the anode monopolar plate is connected to the membrane electrode through a line-surface sealing structure and the upper sealing gasket.

[0016] Preferably, a lower sealing gasket is provided between the cathode monopole and the membrane electrode, and the cathode monopole is connected to the membrane electrode through a line-surface sealing structure and the lower sealing gasket.

[0017] Compared with the prior art, the advantages of the frameless AEM electrolytic cell disclosed in this utility model are as follows: the frameless AEM electrolytic cell eliminates the electrode frame structure, and at the same time sets a sealing structure of line-surface sealing between the electrode plate and the membrane electrode, which can effectively reduce the cost of producing and assembling the electrode frame, improve the performance of the AEM electrolytic cell by reducing the electrode spacing, and reduce the difficulty of disassembly and maintenance. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] like Figure 1 The diagram shown illustrates the working principle of an AEM electrolytic cell.

[0020] like Figure 2 The diagram shown is a schematic diagram of the split structure of a frameless AEM electrolytic cell according to this utility model.

[0021] like Figure 3 The diagram shows the assembly of the electrode plate and sealing gasket in a frameless AEM electrolytic cell according to this invention. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] like Figure 2 and Figure 3As shown, this application discloses a frameless AEM electrolytic cell comprising, from top to bottom, an upper end plate 1, an upper insulating plate 2, an upper current collector 3, an anode monopole plate 4, a membrane electrode 6, a cathode monopole plate 8, a lower current collector 9, a lower insulating plate 10, and a lower end plate 11, connected together. The upper current collector plate 3 and the lower current collector plate 8 are respectively connected to the positive and negative terminals of a power supply. A linear-to-surface sealing structure exists between the anode monopole plate 4 and the membrane electrode 6, and a linear-to-surface sealing structure also exists between the cathode monopole plate 8 and the membrane electrode 6. The anode monopole plate 4 and the cathode monopole plate 8 have flow channels for the flow of alkali solution, water, and gas. Compared with a surface-to-surface sealing structure, the linear-to-surface sealing structure can achieve a tight seal under lower pressure, ensuring no leakage. Therefore, the frameless AEM electrolytic cell can eliminate the electrode frame structure while ensuring sealing performance, achieving the effects of reducing costs, improving performance, and reducing the difficulty of disassembly and maintenance.

[0024] The membrane electrode 6 includes an anion exchange membrane and an encapsulation layer outside the anion exchange membrane. The encapsulation layer is made of PEN film or PPS film. The encapsulation layer improves sealing, reduces the hydrogen content in oxygen, and enhances safety during production. The anode monopole plate 4 and the cathode monopole plate 8 are connected to the encapsulation layer via a line-to-surface sealing structure.

[0025] The anode monopolar plate 4 and cathode monopolar plate 8 are made of nickel-plated carbon steel or pure nickel. Metal plates are less prone to deformation under high temperature and pressure, which could lead to sealing failure. The surface-to-surface sealing structure consists of sealing water ripples on the surfaces of the anode monopolar plate 4 and cathode monopolar plate 8, preferably with a raised height of 0.2 mm. Alternatively, the surface-to-surface sealing structure can be a sealing groove on the surfaces of the anode monopolar plate 4 and cathode monopolar plate 8, filled with sealant or fitted with a sealing ring.

[0026] The upper end plate 1 and the lower end plate 11 are connected to the outside via screws to form external positioning components, thereby providing uniform pressure. The upper end plate 1 and the lower end plate 11 are made of 304 or 316 stainless steel.

[0027] The upper insulating plate 2 forms an insulating layer between the upper end plate 1 and the upper current collector 3, and also forms a pressure buffer layer. The lower insulating plate 10 forms an insulating layer between the lower end plate 11 and the lower current collector 9, and also forms a pressure buffer layer. By setting the upper insulating plate 2 and the lower insulating plate 10, current can be prevented from reaching the end plates, avoiding short circuits caused by the electrolytic cell shell being energized, and also helping to evenly distribute pressure. The upper insulating plate 2 and the lower insulating plate 10 are made of PTF or PPS + 30% glass fiber material.

[0028] The upper current collector 3 and the lower current collector 9 are made of metal with good conductivity and are plated with corrosion-resistant precious metals. Preferably, the upper current collector 3 and the lower current collector 9 are made of copper and plated with gold or platinum.

[0029] Furthermore, an upper sealing gasket 5 can be provided between the anode monopolar plate 4 and the membrane electrode 6. The anode monopolar plate 4 is connected to the membrane electrode 6 through a line-to-surface sealing structure and the upper sealing gasket 5. A lower sealing gasket 7 can be provided between the cathode monopolar plate 8 and the membrane electrode 6. The cathode monopolar plate 8 is connected to the membrane electrode 6 through a line-to-surface sealing structure and the lower sealing gasket 5. The upper sealing gasket 5 and the lower sealing gasket 7 are made of PTFE or EPDM material. Although providing the upper sealing gasket 5 and the lower sealing gasket 7 increases the electrode gap, it can effectively improve the sealing performance.

[0030] See Figure 3 Taking one sealing form of the lower sealing gasket 7 and the cathode monopolar plate 8 as an example, the periphery of the side of the cathode monopolar plate 8 that is connected to the membrane electrode 6 has a sealing part 81, the sealing part 81 has a sealing groove 82, and the sealing groove 82 is filled with a sealing ring 83. The lower sealing gasket 7 and the sealing part 81 correspond in shape in the vertical direction. The sealing part 81 presses the lower sealing gasket 7 upward to achieve a sealed connection between the cathode monopolar plate 8 and the membrane electrode 6.

[0031] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A frameless AEM electrolytic cell, characterized in that, The device includes an upper end plate, an upper insulating plate, an upper current collector, an anode monopole plate, a membrane electrode, a cathode monopole plate, a lower current collector plate, a lower insulating plate, and a lower end plate arranged in sequence. The upper current collector plate and the lower current collector plate are respectively connected to the positive and negative terminals of the power supply. The anode monopole plate and the membrane electrode have a line-to-surface sealing structure, and the cathode monopole plate and the membrane electrode have a line-to-surface sealing structure. The anode monopole plate and the cathode monopole plate have flow channels for the flow of alkaline solution, water, and gas.

2. The frameless AEM electrolytic cell as described in claim 1, characterized in that, The membrane electrode includes an anion exchange membrane and an encapsulation layer outside the anion exchange membrane.

3. The frameless AEM electrolytic cell as described in claim 2, characterized in that, The anode monopole plate is connected to the encapsulation layer through a line-to-surface sealing structure, and the cathode monopole plate is connected to the encapsulation layer through a line-to-surface sealing structure.

4. The frameless AEM electrolytic cell as described in claim 2, characterized in that, The encapsulation layer is a PEN film or a PPS film.

5. The frameless AEM electrolytic cell as described in claim 1, characterized in that, The linear sealing structure is a sealing water ripple line located on the surface of the anode monopole plate and the cathode monopole plate.

6. The frameless AEM electrolytic cell as described in claim 5, characterized in that, The height of the raised watermark line is 0.2mm.

7. The frameless AEM electrolytic cell as described in claim 1, characterized in that, The linear sealing structure is a sealing groove located on the surface of the anode monopole plate and the cathode monopole plate, and the sealing groove is filled with sealant or fitted with a sealing ring.

8. The frameless AEM electrolytic cell as described in claim 1, characterized in that, An upper sealing gasket is provided between the anode monopolar plate and the membrane electrode, and the anode monopolar plate is connected to the membrane electrode through a line-surface sealing structure and the upper sealing gasket.

9. The frameless AEM electrolytic cell as described in claim 1, characterized in that, A lower sealing gasket is provided between the cathode monopole and the membrane electrode, and the cathode monopole is connected to the membrane electrode through a line-surface sealing structure and the lower sealing gasket.

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