Integrated ordered anode assembly of PEM electrolytic bath and PEM electrolytic bath

Abstract

The invention relates to the technical field of electrolytic baths, in particular to an integrated ordered anode assembly of a PEM electrolytic bath and the PEM electrolytic bath. The anode assembly comprises a polar plate structure, a boss runner structure and an ordered diffusion structure which are integrally formed by utilizing a metal powder material through 3D printing. The polar plate structure is provided with an external power interface and a water inlet. Water for electrolysis enters the flow channel structure through the water inlet and reaches the surface of the reaction layer through the diffusion structure for electrochemical reaction. A traditional polar plate structure, a snake-shaped runner structure and a disordered metal felt'sandwich 'laminated structure are broken through, and the polar plate structure, the boss runner structure and the ordered diffusion structure integrated ordered anode assembly are integrally formed through 3D printing by utilizing a metal powder material, so that interface contact resistance between traditional laminated layers can be eliminated, and the performance of the anode assembly is improved. And meanwhile, based on an ordered structure, transmission loss caused by heat and mass transfer is reduced, so that the reaction efficiency is higher, and the weight, the size and the number of components of the electrolytic tank are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of electrolyzers, and in particular to an integrated ordered anode assembly of a PEM electrolyzer and the PEM electrolyzer. Background Art

[0002] The bipolar plates and gas diffusion layers significantly affect the performance of PEM electrolyzers (i.e. proton exchange membrane electrolyzers), especially at high current densities, where the ohmic overpotential and concentration overpotential are the dominant factors in the overall cell voltage.

[0003] In order to improve the performance of PEM electrolyzers, the focus in related technologies is to optimize the structural morphology of bipolar plates or gas diffusion layers. However, related technologies still face problems such as deteriorated heat and mass transfer and high interface contact resistance between stacked structures.

[0004] Therefore, there is an urgent need to provide an integrated ordered anode assembly of a PEM electrolyzer and a PEM electrolyzer to solve the above technical problems. Summary of the invention

[0005] The embodiment of the present invention provides an integrated ordered anode assembly of a PEM electrolyzer and a PEM electrolyzer, which can completely eliminate the interface contact resistance between the bipolar plate and the gas diffusion layer, thereby improving the performance of the PEM electrolyzer.

[0006] In a first aspect, an embodiment of the present invention provides an integrated ordered anode assembly of a PEM electrolyzer, comprising a plate structure, a flow channel structure and an ordered diffusion structure integrally formed by 3D metal printing using metal powder material, wherein the plate structure is used to connect to an external power supply, and an external power supply interface is provided at the edge of the plate structure.

[0007] In a second aspect, an embodiment of the present invention provides a PEM electrolyzer comprising the integrated ordered anode assembly as described in the above embodiment.

[0008] The embodiment of the present invention provides an integrated ordered anode assembly of a PEM electrolyzer and a PEM electrolyzer, wherein a plate structure, a flow channel structure and an ordered diffusion structure are integrally formed by 3D printing using metal materials, thereby eliminating the interface contact resistance between the bipolar plate and the diffusion layer, and the reduction in thickness will form a shorter transmission path, thereby reducing ohmic loss and concentration loss, making the current density of the reaction higher, improving energy utilization and reducing the weight, volume and number of components of the electrolytic cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0010] Figure 1 Schematic diagram of the structure of an integrated ordered anode assembly of a PEM electrolyzer provided by an embodiment of the present invention;

[0011] Figure 2 yes Figure 1 A schematic diagram of the structure of the electrode plate in the integrated ordered anode assembly shown;

[0012] Figure 3 yes Figure 1 A schematic structural diagram of a boss flow channel structure in an integrated ordered anode assembly shown;

[0013] Figure 4 yes Figure 1 Schematic diagram of the structure of the ordered diffusion structure in the integrated ordered anode assembly shown. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0015] Please refer to Figures 1 to 4 An embodiment of the present invention provides an integrated ordered anode assembly of a PEM electrolyzer, including a plate structure, a flow channel structure and an ordered diffusion structure integrally formed by 3D metal printing using metal powder materials, wherein the plate structure is used to connect to an external power supply, and an external power supply interface is provided at the edge of the plate structure.

[0016] In this embodiment, the plate structure 1, the flow channel structure 2 and the ordered diffusion structure 3 are integrally formed by 3D printing using metal materials, so that the interface contact resistance between the bipolar plate and the diffusion layer can be eliminated, and the reduction in thickness will form a shorter transmission path, thereby reducing ohmic loss and concentration loss, making the current density of the reaction higher, improving energy utilization and reducing the weight, volume and number of components of the electrolytic cell.

[0017] In one embodiment of the present invention, the metal powder material includes at least one of stainless steel, nickel alloy and titanium, and the particle size ranges from 15 to 105 μm.

[0018] In one embodiment of the present invention, the electrode plate structure and the diffusion structure are respectively embedded on both sides of the flow channel structure. In one embodiment of the present invention, the electrode plate structure 1 is provided with threaded holes for fixing.

[0019] In one embodiment of the present invention, the diffusion layer adopts a straight through hole structure, which is arranged in an ordered sequential or staggered manner, with a longitudinal spacing of 0.8-1 mm and a lateral spacing of 0.8-1 mm. For example, the straight through holes may include at least one of a circular hole and a polygonal hole.

[0020] In one embodiment of the present invention, the diffusion structure has a thickness of 0.08-0.5 mm, and the through hole includes at least one of a circular hole and a polygonal hole.

[0021] In one embodiment of the present invention, the flow channel structure adopts a boss structure, the cross-sectional area of ​​the boss structure gradually increases from the plate direction to the diffusion structure direction, and the area ratio of the two sides is 1 to 1.5, which is used to increase the radial transmission speed of water. For example, the boss structure can be a cylinder, a quadrangular boss structure, or a hexagonal boss structure.

[0022] In one embodiment of the present invention, the thickness of the flow channel structure layer is 1 to 1.5 mm, and each boss is inlaid with the solid part of the diffusion structure to ensure the coordinated transmission of electrons, water and gas.

[0023] In one embodiment of the present invention, the outer surface of the diffusion structure is smoothed to fully contact with the external reaction layer of the component.

[0024] It should be noted that the boss structure in the integrated ordered anode assembly is designed to make the reactants more evenly distributed, and the front and rear boss spacings are set the same so that the small bosses are evenly distributed on the diffusion layer interface, and in order to ensure the conductive performance, the contact area between the boss and the diffusion layer is consistent with that of other conventional flow fields, and a certain inclination angle is set for the traditional right prism to make it a boss structure, which makes it easier for liquid water to diffuse downward to the diffusion layer interface when flowing into the flow channel; the straight-through hole structure in the ordered diffusion structure is also evenly spaced, so that liquid water can easily reach the surface of the catalyst layer to react, and the porosity of the diffusion layer of the straight-through hole structure is consistent with the porosity of the traditional diffusion layer titanium felt structure, and the straight-through hole structure can achieve iteration from disorder to order compared with the traditional diffusion layer titanium felt structure, so that the liquid water in the straight-through hole structure can reach the reaction interface more fully at the same porosity, and the oxygen bubbles generated by the reaction can be more easily discharged.

[0025] The principle of the above scheme is as follows:

[0026] The integrated ordered anode assembly consists of a plate structure 1, a boss flow channel structure 2 and an ordered diffusion structure 3, all of which are custom designed. The flow channel adopts a boss flow channel structure, which is an improvement on the traditional needle-type flow field. It can make liquid water react more fully, reduce pressure drop, and promote the reaction. A common problem with the traditional needle type is the large-area stagnation point where the backflow contacts the airflow, forming a slug flow, which requires a larger pressure drop to overcome. The use of this structure can effectively solve this problem and reduce the possibility of bubbles adhering to the ribs, so that liquid water can quickly flush away the bubbles. The conventional serpentine flow channel has reactant uniformity and parallel flow channels have low pressure drop. Compared with conventional parallel flow channels, liquid water can be more evenly distributed on the surface of the diffusion layer and the catalyst layer, thereby improving the reaction of liquid water. Compared with conventional serpentine flow channels, high current density can be better obtained under low pressure drop. The ordered diffusion structure adopts a straight-through hole design. Because during the water electrolysis reaction, bubbles are only generated, grown and detached at the edges of the pores, and almost no bubbles are generated in the center. The use of straight-through holes can effectively reduce the transmission resistance of liquid water, so that liquid water can react more fully at the interface of the catalyst layer, and bubbles can be more easily washed away, increasing the area where the liquid water under the original ribs does not react, allowing the reactants and products to react more fully. In addition, this layer is smoothed to make it in more uniform contact with the catalyst layer, with good thermal conductivity and electrical conductivity, increasing active sites, and reducing contact resistance and activating reaction sites.

[0027] In summary, the anode assembly includes a plate structure, a boss flow channel structure and an ordered diffusion structure that are integrally formed by 3D printing using metal powder materials. The plate structure is provided with an external power supply interface and a water inlet. The water used for electrolysis enters the flow channel structure through the water inlet, and reaches the surface of the reaction layer through the diffusion structure for electrochemical reaction. The present invention breaks the traditional plate structure, serpentine flow channel structure and disordered metal felt "sandwich" laminated structure, and uses metal powder materials to integrally form a plate structure, a boss flow channel structure and an ordered diffusion structure through 3D printing to form an integrated ordered anode assembly. This can eliminate the interface contact resistance between the traditional laminates, and at the same time, based on the ordered structure, reduce the transmission loss caused by heat and mass transfer, so that the reaction efficiency is higher, and the weight, volume and number of components of the electrolytic cell are reduced.

[0028] That is, the above-mentioned integrated ordered anode assembly integrates the four conventional components of the PEM electrolyzer (i.e., diffusion layer, bipolar plate, gasket and current distributor) into a multifunctional AM plate (i.e., integrated ordered anode assembly) (wherein, additive manufacturing (i.e., AM) technology allows materials to be three-dimensionally printed from three-dimensional digital models, which can provide cost- and time-efficient components with complex 3D structures), eliminates the interface contact resistance between the bipolar plate and the diffusion layer, and the reduction in thickness will form a shorter transmission path, wherein the flow field part adopts a new type of boss flow channel structure, which can simultaneously achieve low pressure and make the reactants more uniform, and the diffusion layer also adopts a new type of ordered diffusion structure to reduce the transmission resistance of liquid water, making it easier for bubbles to be washed away and the reaction is more sufficient. The multifunctional AM plate can reduce ohmic loss and concentration polarization loss, so that its current density is higher, improve energy utilization and reduce the weight, volume and number of components of the electrolytic cell.

[0029] In addition, an embodiment of the present invention further provides a PEM electrolyzer, comprising an integrated ordered anode assembly as mentioned in any of the above embodiments.

[0030] It is understandable that the PEM electrolyzer provided in this embodiment has the same beneficial effects as the integrated ordered anode assembly mentioned in the above embodiment, which will not be described in detail here.

[0031] It should be noted that the present application does not disclose specific technical details on how to use pre-set standard lumbar manipulation to evaluate the lumbar manipulation to be evaluated. Those skilled in the art can understand that curve comparison or other evaluation methods can be used, which will not be elaborated here.

[0032] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0033] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An integrated ordered anode assembly for a PEM electrolyzer, characterized in that: It includes a plate structure, a flow channel structure and an ordered diffusion structure which are integrally formed by 3D metal printing using metal powder materials. The plate structure is used to connect to an external power source, and an external power source interface is provided at the edge of the plate structure.

2. The integrated ordered anode assembly according to claim 1, characterized in that: A water inlet is arranged on the side of the electrode plate structure, and water for electrolysis enters the flow channel structure through the water inlet and reaches the surface of the reaction layer through the diffusion structure to perform electrochemical reaction.

3. The integrated ordered anode assembly according to claim 1, characterized in that: The metal powder material includes at least one of stainless steel, nickel alloy and titanium, and the particle size ranges from 15 to 105 μm.

4. The integrated ordered anode assembly according to claim 1, characterized in that: The two sides of the flow channel structure are respectively inlaid with a plate structure and a diffusion structure.

5. The integrated ordered anode assembly according to claim 1, characterized in that: The diffusion structure is provided with straight through hole structures, which are arranged in an orderly sequential or staggered manner, with a longitudinal spacing of 0.8 to 1 mm and a lateral spacing of 0.8 to 1 mm.

6. The integrated ordered anode assembly according to claim 1, characterized in that: The diffusion structure has a thickness of 0.08-0.5 mm, and the through hole includes at least one of a circular hole and a polygonal hole.

7. The integrated ordered anode assembly according to claim 1, characterized in that: The outer surface of the diffusion structure is smoothed to fully contact with the external reaction layer of the component.

8. The integrated ordered anode assembly according to claim 1, characterized in that: The flow channel structure adopts a boss structure, the cross-sectional area of ​​the boss structure gradually increases from the direction of the electrode plate to the direction of the diffusion structure, and the area ratio on both sides is 1 to 1.5, which is used to increase the radial transmission speed of water.

9. The integrated ordered anode assembly according to claim 1, characterized in that: The thickness of the flow channel structure layer is 1 to 1.5 mm, and each boss is inlaid with the solid part of the diffusion structure to ensure the coordinated transmission of electrons, water and gas.

10. A PEM electrolyzer, characterized in that: The invention comprises the integrated ordered anode assembly as claimed in any one of claims 1 to 9.

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