WO2024078190A1

WO2024078190A1 - Metal electrode frame for electrolyzing water to produce hydrogen, electrolysis units, electrolytic cell and assembly jig

Info

Publication number: WO2024078190A1
Application number: PCT/CN2023/116802
Authority: WO
Inventors: 崔少平; 巨攀龙; 李丰博; 朱金超; 朱琛; 廖多香; 臧丽丽
Original assignee: 无锡隆基氢能科技有限公司
Priority date: 2022-10-10
Filing date: 2023-09-04
Publication date: 2024-04-18
Also published as: CN218842350U

Abstract

The present application relates to a metal electrode frame for electrolyzing water to produce hydrogen, electrolysis units, an electrolytic cell and an assembly jig. The electrode frame is annular, and an inner peripheral surface of the electrode frame is configured to connect to an electrode plate directly; a first step portion configured to mount a diaphragm and a second step portion configured to mount a first electrode are arranged on a first side face of the electrode frame at a gradually reducing height from outside to inside; and a third step portion configured to mount a second electrode is arranged on a second side face of the electrode frame. According to the technical solution, the inner peripheral surface of the electrode frame is configured to connect to the electrode plate directly, the time spent on machining a tongue plate can be avoided, the production efficiency of the electrode frame is improved, and the area of electrode plates which can be arranged in the electrode frame is also increased, which improves the electrolysis efficiency. In addition, the electrode frame connects to the electrode plate directly, such that the position relationship between the electrode frame and the electrode plate and the sealing performance of the position where the electrode frame is connected to the electrode plate can be more effectively ensured. The step portions can accommodate the diaphragm and the electrodes required by electrolysis and also reduce the weight of the electrode frame, and positioning and installation of the diaphragm and the electrodes are facilitated.

Description

Metal pole frames, electrolysis units, electrolyzers and assembly jigs for electrolysis of water to produce hydrogen

This application claims the priority of the Chinese patent application filed with the China Patent Office on October 10, 2022, with application number 202222663899.8 and invention name “Metal electrode frame, electrolysis unit, electrolysis cell and assembly fixture for electrolysis of water to produce hydrogen”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of hydrogen production by alkaline water electrolysis, and in particular, to a metal pole frame, an electrolysis unit, an electrolytic cell and an assembly jig for producing hydrogen by electrolysis of water.

Background technique

At present, the filter press type bipolar electrolyzer structure is generally used in the field of hydrogen production by alkaline water electrolysis. This electrolyzer structure includes several electrolysis units, and the electrolysis unit is mainly formed by welding the main pole plate and the pole frame through two-protection welding. In order to ensure the sealing between the main pole plate and the pole frame and avoid thermal deformation at the welding point between the main pole plate and the pole frame, the related technology usually sets a tongue plate as a connecting piece between the main pole plate and the pole frame (see Figure 1). The tongue plate can avoid thermal deformation at the welding point between the main pole plate and the pole frame, so that the main pole plate and the pole frame will not be damaged during the installation process. However, the tongue plate needs to be processed on the pole frame additionally, and the processing accuracy is greatly affected by the processing machinery, which reduces the production efficiency of the pole frame. At the same time, the tongue plate increases the weight of the pole frame and occupies the area of the pole piece. The reduction of the pole piece area increases the current density in the electrolyzer, thereby affecting the effect of electrolysis.

Summary of the invention

The first object of the present application is to provide a metal pole frame for producing hydrogen by electrolyzing water, so as to at least partially solve the problems existing in the related art.

In order to achieve the above-mentioned purpose, the present application provides a metal pole frame for electrolyzing water to produce hydrogen, wherein the pole frame is annular, and the inner circumferential surface of the pole frame is used to directly connect with the pole piece, and the first side surface of the pole frame is provided with a first step portion for installing a diaphragm and a second step portion for installing a first electrode in a gradually decreasing height from the outside to the inside, and the second side surface of the pole frame is provided with a third step portion for installing a second electrode.

Optionally, a protrusion and a fourth step portion are further provided on the first side surface and the second side surface. The protrusion is provided on the outer peripheral edges of the first side surface and the second side surface, and is used to make the two adjacent pole frames seal and abut; the fourth step portion is provided between the protrusion on the first side surface and the first step portion and between the protrusion on the second side surface and the second step portion, and is used to install a sealing ring.

Optionally, a liquid inlet and a liquid outlet are provided on the pole frame, and a liquid storage cavity for storing electrolyte is formed on both sides of the pole piece and the inner peripheral space of the pole frame, and the liquid outlet and the liquid inlet are respectively connected to the liquid storage cavity.

Optionally, the liquid outlet hole and the liquid inlet hole are arranged radially symmetrically with respect to the pole frame 1 , and there are a plurality of the liquid outlet hole 18 and a plurality of the liquid inlet hole 17 .

Optionally, a nickel layer is provided on the outer surface of the pole frame.

The second object of the present application is to provide an electrolysis unit, comprising a pole frame and a pole piece, wherein the pole frame is a metal pole frame for producing hydrogen by electrolyzing water as described in any one of the above items, and the pole piece is arranged in the inner peripheral space of the pole frame, and the pole piece is directly connected to the inner peripheral surface of the pole frame as a whole.

Optionally, the pole piece is connected to the pole frame by laser welding, the weld is a fillet weld or a butt weld, the weld height of the fillet weld is 0.1mm-2mm; the weld height of the butt weld is 0.1mm-2mm, and the assembly gap is 0.05mm~1mm.

The third object of the present application is to provide an electrolytic cell comprising a plurality of electrolytic units which are stacked and sealed, wherein the electrolytic units are any of the electrolytic units described above.

The fourth object of the present application is to provide an assembly jig for assembling the electrolytic unit described in any one of the above-mentioned items, wherein the assembly jig is disc-shaped, comprising a first bearing portion for bearing the pole piece and a second bearing portion arranged at the outer peripheral edge of the first bearing portion and lowered in height relative to the first bearing portion, wherein the second bearing portion cooperates with the pole frame to limit the horizontal displacement of the pole frame.

Optionally, the height difference between the first bearing portion and the second bearing portion is configured such that the pole piece is located in the middle position in the height direction of the inner circumference of the pole frame.

Through the above technical solution, the inner circumference of the pole frame is used to directly connect with the pole piece, which can avoid wasting time on processing the tongue plate during the production of the pole frame, thereby improving the production efficiency of the pole frame. The direct connection between the pole frame and the pole piece also increases the area of the pole piece that can be set in the pole frame, thereby improving the electrolysis efficiency during the electrolysis process. At the same time, since the processing accuracy of the tongue plate is greatly affected by the processing machinery, the direct connection between the pole frame and the pole piece can be more The positional relationship between the pole frame and the pole piece and the sealing of the connection are effectively ensured. The sides of the pole frame are provided with multiple steps, which can accommodate the diaphragm and electrode required for electrolysis and further reduce the weight of the pole frame, making it easier to position and install the diaphragm and electrode.

Other features and advantages of the present application will be described in detail in the subsequent specific implementation section.

The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of the structure of an electrolysis unit in the related art;

FIG2 is a schematic diagram of the structure of an electrolysis unit provided in an exemplary embodiment of the present application;

3 and 4 are cross-sectional views taken along line X in FIG. 1 ;

Fig. 5 is an enlarged view of part I in Fig. 3;

Fig. 6 is an enlarged view of part II in Fig. 4;

FIG. 7 is a schematic structural diagram of an assembly jig provided in an exemplary embodiment of the present application when in use.

Description of reference numerals:
1-pole frame, 11-first side, 12-first step portion, 13-second step portion, 14-second side, 15-third step portion, 16-protrusion, 17-liquid inlet hole, 18-liquid outlet hole, 19-liquid storage cavity, 2-pole piece, 3-weld seam, 4-assembly fixture, 41-first bearing portion, 42-second bearing portion, 5-fourth step portion, 6-tongue plate.

Specific embodiments

In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

In this application, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the orientation of the relevant components in actual use, and specifically refer to the drawing directions of Figures 3 and 4. "Inside" and "outside" refer to the inside and outside of the corresponding component outline. In addition, when the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The terms "first", "second", etc. used in this application are to distinguish one element from another element and do not have order and importance.

The present application provides a metal pole frame 1 for electrolyzing water to produce hydrogen. As shown in FIG. 2 to FIG. 7, the pole frame 1 is annular, and the inner circumference of the pole frame 1 is used to directly connect with the pole piece 2. For example, the pole piece 2 is welded to the inner circumference of the pole frame 1 in the form of laser welding. The first side surface 11 of the pole frame 1 is provided with a first step portion 12 for installing the diaphragm and a second step portion 13 for installing the first electrode, which are gradually reduced in height from the outside to the inside (i.e., from the outer circumference of the ring inward along the radial direction), and the second side surface 14 of the pole frame 1 is provided with a third step portion 15 for installing the second electrode. Specifically, the diaphragm can block the gas without blocking the electrolyte. When the first electrode is a positive electrode, the second electrode needs to be a negative electrode. Conversely, it is necessary to ensure that the polarities of the first electrode and the second electrode are opposite. For the convenience of description, the upper side of the drawing direction of FIG. 3 and FIG. 4 is referred to as the first side, and the lower side of the drawing direction is referred to as the second side.

Through the above technical solution, the inner circumference of the pole frame 1 is used to directly connect with the pole piece 2. When the pole frame 1 is produced, it can avoid spending time on processing the tongue plate 6, thereby improving the production efficiency of the pole frame 1. The direct connection between the pole frame 1 and the pole piece 2 also increases the area of the pole piece 2 that can be set in the pole frame 1, thereby improving the electrolysis efficiency during the electrolysis process. At the same time, since the processing accuracy of the tongue plate 6 is greatly affected by the processing machinery, the direct connection between the pole frame 1 and the pole piece 2 can more effectively ensure the positional relationship between the pole frame 1 and the pole piece 2 and the sealing of the connection. The side surfaces of the pole frame 1 are respectively provided with a plurality of step portions, which can accommodate the diaphragm and electrode required for electrolysis while further reducing the weight of the pole frame 1, thereby facilitating the positioning and installation of the diaphragm and the electrode.

Furthermore, a protrusion 16 and a fourth step portion 5 are also provided on the first side surface 11 and the second side surface 14. The protrusion 16 is provided on the outer peripheral edge of the first side surface 11 and the second side surface 14, and is used to seal and abut two adjacent pole frames 1; the fourth step portion 5 is provided between the protrusion 16 on the first side surface 14 and the first step portion 12, and between the protrusion 16 on the second side surface 14 and the second step portion 5. 13, for installing the sealing ring. In this way, when multiple pole frames 1 need to be stacked for use, the adjacent pole frames 1 will not be affected by the thickness of the diaphragm and the electrode. When stacking, the second side 14 of the pole frame 1 located at the top can be sealed with the first side 11 of the pole frame 1 located at the bottom through the protrusion 16. After the multiple pole frames 1 are stacked and fixed, the leakage of electrolyte caused by the gap between the pole frames 1 when stacked is avoided. At the same time, the protrusion 16 can be provided with a protrusion and a groove (not shown in the figure) for easy positioning and installation. For example, a protrusion can be provided on the first side 11 of the pole frame 1, and a groove that can cooperate with the protrusion can be provided on the second side 14. In this way, the protrusion and the groove cooperate with each other to make the pole frame 1 more convenient to position when stacked. Optionally, the outer surface of the protrusion 16 can be a polished surface, and the outer surface of the protrusion 16 includes the outer peripheral surface and the side of the protrusion 16, so that when the protrusions 16 are mutually attached, the gap generated is smaller, further reducing the risk of electrolyte leakage. The sealing ring installed in the fourth step portion 5 can further improve the sealing performance when multiple pole frames 1 need to be stacked for use. The sealing ring can be made of corrosion-resistant elastic material, because the electrolyte is alkaline, and the corrosion-resistant material can increase the service life of the sealing ring. In addition, the elastic material allows the sealing ring to rebound elastically when squeezed to avoid the appearance of gaps, thereby ensuring the use effect of the sealing ring.

In the present application, the pole frame 1 is provided with a liquid inlet hole 17 and a liquid outlet hole 18, and the two side surfaces of the pole piece 2 and the inner peripheral space of the pole frame 1 form a liquid storage cavity 19 for storing electrolyte, and the liquid outlet hole 18 and the liquid inlet hole 17 are respectively connected to the liquid storage cavity 19. Among them, the liquid storage cavity 19 is used to contain electrolyte, and the liquid outlet hole 18 and the liquid inlet hole 17 are respectively connected to the liquid storage cavity 19. The liquid inlet hole 17 can replenish electrolyte into the liquid storage cavity 19 and recover oxygen generated during the electrolysis process, and the liquid outlet hole 18 can collect hydrogen generated during the electrolysis operation and recover the electrolyzed electrolyte. The liquid outlet 18 and the liquid inlet 17 can be specifically set with reference to FIG. 2 while ensuring communication with the liquid storage chamber 19, that is, the liquid outlet 18 and the liquid inlet 17 can pass through the pole frame 1 from top to bottom, so that when multiple pole frames 1 are stacked, the liquid storage chambers 19 of multiple pole frames 1 can be connected to each other, and the electrolyte can be replenished into the liquid storage chambers 19 of multiple pole frames 1 and the oxygen generated during the electrolysis process can be recovered through the liquid inlet 17. The liquid outlet 18 can also collect the hydrogen generated by the liquid storage chambers 19 of multiple pole frames 1 during the electrolysis operation and recover the electrolyzed electrolyte. At the same time, the liquid outlet 18 and the liquid inlet 17 are arranged radially symmetrically relative to the pole frame 1, and the liquid outlet 18 and the liquid inlet 17 can also have multiple. Multiple liquid outlets 18 and liquid inlet 17 can operate simultaneously to further improve the electrolysis efficiency.

The outer surface of the pole frame 1 may be provided with a nickel layer. For example, in the operation of producing hydrogen by electrolysis of alkaline water, A lot of alkaline ions will be generated, and these alkaline ions will corrode the pole frame 1 and reduce the service life of the pole frame 1. Therefore, a nickel layer can be provided on the outer surface of the pole frame 1 to prevent the alkaline ions from corroding the outer surface of the pole frame 1. At the same time, the nickel layer can also improve the wear resistance of the outer surface of the pole frame 1, and improve the service life and use strength of the pole frame 1. The nickel layer can be provided by electroplating to ensure that the nickel layer is evenly and firmly provided.

The second object of the present application is to provide an electrolysis unit, comprising a pole frame 1 and a pole piece 2, wherein the pole piece 2 is arranged in the inner peripheral space of the pole frame 1, and the pole piece 2 is directly connected to the inner peripheral surface of the pole frame 1 as a whole. The pole frame 1 is a metal pole frame 1 for producing hydrogen by electrolyzing water in any of the above-mentioned embodiments, and has all its beneficial effects, which will not be repeated here.

In some embodiments, the pole piece 2 can be connected to the pole frame 1 by laser welding. Laser welding is fast and efficient, and is suitable for a variety of environments. At the same time, laser welding mainly transmits energy to the deep part of the workpiece, with less lateral diffusion. Therefore, the weld 3 produced by laser welding is smaller and the shape is better controlled. After laser welding, the pole frame 1 and the pole piece 2 do not need to be corrected or processed again to ensure the strength of the weld. Compared with the two-way welding method, it can ensure the sealing between the pole frame 1 and the pole piece 2 and avoid thermal deformation at the welding point of the pole frame 1 and the pole piece 2.

The weld 3 may be a fillet weld or a butt weld, specifically referring to FIG. 5 and FIG. 6 , the weld 3 shown in FIG. 5 is a fillet weld, and its shape is generally an isosceles right triangle, so that the two right-angled sides of the fillet weld can be connected to the pole frame 1 and the pole piece 2 with the same size, ensuring that the force of the fillet weld is more uniform, so as to ensure the strength of the laser welding, and at the same time, no gap is generated between the pole piece 2 and the pole frame 1, specifically, the weld height of the fillet weld is represented by the straight line distance A in FIG. 5 , which may be 0.1 mm-2 mm. In addition, the weld 3 shown in FIG. 6 is a butt weld, in which the weld height represents the part of the upper and lower ends of the weld 3 that exceeds the upper and lower sides of the pole piece 2, and the pair gap represents the spacing between the outer peripheral surface of the pole piece 2 and the inner peripheral surface of the pole frame 1, specifically, the weld height of the butt weld is represented by the straight line distance A in FIG. 6 , which may be 0.1 mm-2 mm, and the pair gap of the butt weld is represented by the straight line distance B in FIG. 6 , which may be 0.05 mm-1 mm. In this way, no matter how the thickness of the pole piece 2 is changed, the installation conditions of the pole frame 1 and the pole piece 2 can be met, and the size of the weld 3 will not affect the electrolysis operation.

The third object of the present application is to provide an electrolytic cell, comprising a plurality of electrolytic units stacked and sealed, wherein the electrolytic unit is an electrolytic unit of any of the above embodiments and has all the advantages thereof. The beneficial effects will not be elaborated here.

The fourth object of the present application is to provide an assembly jig 4 for assembling an electrolytic unit of any of the above-mentioned embodiments, and having all its beneficial effects, which will not be described in detail here. The assembly jig 4 is disc-shaped, including a first bearing portion 41 for bearing the pole piece 2 and a second bearing portion 42 arranged at the outer peripheral edge of the first bearing portion 41 and lowered in height relative to the first bearing portion 41, and the second bearing portion 42 cooperates with the pole frame 1 to limit the horizontal displacement of the pole frame 1. The first bearing portion 41 can support the pole piece 2, and the second bearing portion 42 limits the displacement of the pole frame 1. When the pole frame 1 is fixed, taking the weld 3 as a fillet weld 3 as an example, the outer periphery of the pole piece 2 can be transitionally matched with the inner periphery of the pole frame 1. Taking the weld 3 as a butt weld as an example, a groove for fixing the pole piece 2 can be designed on the surface of the first bearing portion 41, so that the pole frame 1 and the pole piece 2 will not be misaligned during the welding process.

The height difference between the first bearing portion 41 and the second bearing portion 42 is configured so that the pole piece 2 is located in the middle position in the height direction of the inner peripheral surface of the pole frame 1. In this way, the two liquid storage chambers 19 in the upper and lower directions of the pole piece 2 can accommodate the same volume of electrolyte, which facilitates the stacking and sealing installation of multiple electrolytic units to form an electrolytic cell, and is more convenient for electrolysis operations.

The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings; however, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, a variety of simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the protection scope of the present application.

It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not further describe various possible combinations.

In addition, the various implementation modes of the present application may be arbitrarily combined, and as long as they do not violate the concept of the present application, they should also be regarded as the contents disclosed in the present application.

The term "one embodiment", "embodiment" or "one or more embodiments" herein means that a particular feature, structure or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present application. In addition, please note that the examples of the term "in one embodiment" here do not necessarily all refer to the same embodiment.

In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

In the claims, any reference signs placed between brackets shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application 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 replace some of the technical features therein with equivalents. 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 application.

Claims

A metal pole frame for producing hydrogen by electrolyzing water, characterized in that the pole frame is annular, and the inner circumferential surface of the pole frame is used to directly connect with the pole piece, the first side surface of the pole frame is provided with a first step portion for installing a diaphragm and a second step portion for installing a first electrode in a manner that gradually decreases in height from the outside to the inside, and the second side surface of the pole frame is provided with a third step portion for installing a second electrode.
The metal pole frame for producing hydrogen by electrolysis of water according to claim 1 is characterized in that a protrusion and a fourth step portion are also provided on the first side and the second side, and the protrusion is provided on the outer peripheral edge of the first side and the second side, and is used to make the two adjacent pole frames seal and abut; the fourth step portion is provided between the protrusion on the first side and the first step portion and between the protrusion on the second side and the second step portion, and is used to install a sealing ring.
The metal pole frame for producing hydrogen by electrolysis of water according to claim 1 is characterized in that a liquid inlet hole and a liquid outlet hole are provided on the pole frame, and a liquid storage cavity for storing electrolyte is formed on the two side surfaces of the pole piece and the inner peripheral space of the pole frame, and the liquid outlet hole and the liquid inlet hole are respectively connected to the liquid storage cavity.
According to the metal pole frame for producing hydrogen by electrolysis of water as claimed in claim 3, it is characterized in that the liquid outlet hole and the liquid inlet hole are arranged radially symmetrically relative to the pole frame, and there are a plurality of the liquid outlet hole and the liquid inlet hole respectively.
The metal pole frame for producing hydrogen by electrolysis of water according to claim 1, characterized in that a nickel layer is provided on the outer surface of the pole frame.
An electrolysis unit, characterized in that it includes a pole frame and a pole piece, wherein the pole frame is a metal pole frame for electrolyzing water to produce hydrogen as described in any one of claims 1 to 5, and the pole piece is arranged in the inner peripheral space of the pole frame, and the pole piece is directly connected to the inner peripheral surface of the pole frame as a whole.
The electrolytic unit according to claim 6 is characterized in that the pole piece is connected to the pole frame by laser welding, the weld on the pole piece is a fillet weld or a butt weld, the weld height of the fillet weld is 0.1mm-2mm; the weld height of the butt weld is 0.1mm-2mm, and the assembly gap is 0.05mm~1mm.
An electrolytic cell, characterized in that it comprises a plurality of electrolytic units which are stacked and sealed, wherein the electrolytic units are the electrolytic units according to claim 6 or 7.
An assembly jig, characterized in that it is used to assemble the electrolytic unit described in claim 6 or 7, the assembly jig is disc-shaped, including a first bearing portion for bearing a pole piece and a second bearing portion arranged at the periphery of the first bearing portion and lowered in height relative to the first bearing portion, the second bearing portion being used to cooperate with the pole frame to limit the horizontal displacement of the pole frame.
The assembly jig according to claim 9 is characterized in that the height difference between the first bearing portion and the second bearing portion is configured so that the pole piece is located in the middle position of the height direction of the inner circumference of the pole frame.