An electrolytic cell and electrolytic module for producing hydrogen by low-pressure water electrolysis

Abstract

The present invention discloses an electrolyzer and electrolysis module for producing hydrogen by low-pressure water electrolysis, comprising: a cathode frame and an anode frame, wherein the cathode frame and the anode frame are separated by a diaphragm, and are used to electrolyze alkaline solution to produce hydrogen in the cathode cavity in the cathode frame and oxygen in the anode cavity in the anode frame. A diaphragm electrode assembly, wherein the diaphragm electrode assembly comprises a cathode mesh, a diaphragm and an anode mesh. A supporting conductive assembly is also provided, wherein the supporting conductive assembly is partially attached to the side wall of the diaphragm electrode assembly, and a fixing portion extending toward the supporting conductive assembly is provided in the cathode frame and the cathode frame, and the top of the fixing portion on at least one side elastically abuts against the diaphragm electrode assembly through the supporting conductive assembly. In the process of producing hydrogen by electrolysis, it is prevented that the two sides of the diaphragm are damaged by shaking in the electrolyzer due to the unstable pressure difference.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolyzers, and in particular to an electrolyzer and an electrolysis module for producing hydrogen by low-pressure water electrolysis. Background Art

[0002] In the electrolyzer for producing hydrogen by water electrolysis, the cathode and anode nets are made of woven nets, which are supported by ribs or concave-convex structures. The woven nets between the ribs or concave-convex structures will have depressions, resulting in uneven nets. In addition, there is a certain gap between the cathode and anode nets and the diaphragm. Due to the depression of the woven net, the gap between the net and the diaphragm is uneven. The water electrolysis membrane generally uses a pps diaphragm, which has flexible characteristics. When working, there will be an unstable pressure difference between the cathode and anode sides. This pressure difference is due to the different volumes of gas generated in the cathode and anode cavities per unit time, and the diaphragm will swing with the pressure difference.

[0003] Therefore, there is still a need for an electrolyzer and an electrolysis module for producing hydrogen by low-pressure water electrolysis to solve the above problems. Summary of the invention

[0004] The present invention provides an electrolytic cell and an electrolytic module for producing hydrogen by low-pressure water electrolysis to solve the above-mentioned problems.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] An electrolyzer for producing hydrogen by low-pressure water electrolysis, comprising:

[0007] A cathode frame and an anode frame, wherein the cathode frame and the anode frame are separated by a diaphragm and are used to electrolyze alkaline solution to generate hydrogen in the cathode cavity of the cathode frame and oxygen in the anode cavity of the anode frame;

[0008] A membrane electrode assembly, the membrane electrode assembly comprising a cathode mesh, a membrane and an anode mesh;

[0009] A supporting conductive component is also provided, which is partially attached to the side wall of the diaphragm electrode assembly. The cathode frame and the cathode frame are provided with a fixing portion extending toward the supporting conductive component, and the top of the fixing portion on at least one side abuts the diaphragm electrode assembly through the supporting conductive component.

[0010] In one embodiment, the membrane electrode assembly includes a cathode mesh, a membrane and an anode mesh;

[0011] The supporting conductive component comprises: a buffer net and a supporting net, wherein the buffer net and the supporting net are stacked, the top of the supporting conductive component abuts against the buffer net through the supporting net, and the buffer net elastically abuts against one side of the cathode net and / or the anode net, so that the diaphragm elastically abuts between the cathode net and the anode net.

[0012] In one embodiment, the edges of the cathode mesh and / or the anode mesh are turned outward to cover the edges of the adjacent buffer mesh and the support mesh.

[0013] In one embodiment, in the anode chamber, the anode mesh is welded to the bottom of the support tube, the partition is welded to the top of the support tube, the pole frame is welded to the end of the partition away from the support tube, and a gasket is connected to the other side of the pole frame relative to the welding point between the pole frame and the partition, and the top of at least a portion of the diaphragm is elastically abutted by the gasket.

[0014] In one embodiment, in the cathode cavity, the edge of the cathode mesh is turned outward to cover the edges of the adjacent buffer mesh and the support mesh, the partition is welded to the bottom of the support tube, and the pole frame is welded through the partition, and a gasket is bonded to the pole frame near the edge, and the gasket elastically abuts against at least part of the bottom of the diaphragm.

[0015] In one embodiment, after combination, the thickness of the gasket is H. In a relaxed state, the height of the anode mesh is lower than the thickness h1 of the gasket located on the side close to the anode cavity, and the height of the cathode mesh is higher than the thickness h2 of the gasket located on the side close to the cathode cavity. The h1 is 0.5-0.6 mm, and the h2 is 2.5-2.9 mm.

[0016] In one embodiment, the compression amount of the cushioning net does not exceed 58% of the height of the cushioning net in a relaxed state.

[0017] In one embodiment, it comprises a plurality of electrolytic cells, electrolytic cells and power supply devices as described in any one of the above, wherein the electrolytic cells contain alkaline solution, the cathode network, diaphragm and anode network of the electrolytic cells are placed in the alkaline solution, and the power supply device is electrically connected to the cathode network and the anode network to provide electrical energy.

[0018] Compared with the prior art, the beneficial effects of the present invention include at least:

[0019] The conductive support component is elastically fitted on one or both sides of the diaphragm electrode assembly, and a fixing portion extending in the direction of the conductive support component is respectively provided on the cathode frame and the anode frame. Under the elastic contact between the fixing portion and the conductive support component, the positions of the two sides of the diaphragm are fixed to prevent the two sides of the diaphragm from shaking in the electrolyzer due to the small voltage difference during the process of hydrogen production by electrolysis and being damaged. At the same time, the cathode net and the anode net are tightly fitted on both sides of the diaphragm under the elastic squeezing of the two adjacent pole frames, maintaining a zero gap between the membrane and the poles, so that the resistance between the cathode net and the anode net is small, the power loss is reduced, and the heat generated by the electrolytic cell is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the electrolytic cell structure of an embodiment of the present invention;

[0021] Figure 2 Schematic diagram of the internal structure of the cathode electrolysis chamber of an embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of the internal structure of part of the anode electrolysis chamber of an embodiment of the present invention.

[0023] In the figure: 1, anode cavity; 2, cathode cavity; 3, diaphragm; 4, anode mesh; 5, support tube; 6, support mesh; 7, buffer mesh; 8, cathode mesh; 9, pole frame; 10, gasket; 11, partition. DETAILED DESCRIPTION

[0024] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete and to fully convey the concepts of example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0025] The words expressing positions and directions described in the present invention are all explained with reference to the accompanying drawings as examples, but they can be changed as needed, and all such changes are included in the protection scope of the present invention.

[0026] Reference Figure 1-3 The present invention provides an electrolyzer for producing hydrogen by low-pressure water electrolysis, comprising a cathode frame and an anode frame, wherein the cathode frame and the anode frame are separated by a diaphragm 3, and are used to electrolyze alkaline solution to generate hydrogen in the cathode cavity 2 in the cathode frame and oxygen in the anode cavity 1 in the anode frame. The alkaline solution is, for example, a 30% mass concentration KOH solution or a 26% mass concentration NaOH solution.

[0027] The diaphragm 3 electrode assembly includes a cathode mesh 8, a diaphragm 3 and an anode mesh 4. The two-layer metal mesh structure of the cathode mesh 8, the diaphragm 3 and the anode mesh 4 is respectively attached to the upper side and the lower side of the diaphragm 3, wherein an electric field is formed between the cathode mesh 8 and the anode mesh 4 in the electrolytic cell after the power is turned on, and ions are driven to exchange through the diaphragm 3. Since the cathode mesh 8 and the anode mesh 4 are respectively attached to both sides of the diaphragm 3 with zero spacing, when the power supply provides electrical energy, the spacing between the anode mesh 4 and the cathode mesh 8 is small, so that the resistance between the anode and cathode electrodes is small, the heat generated in the electrolytic cell when the electrolytic cell is used to produce hydrogen by electrolysis is reduced, the power consumption is reduced, and the hydrogen production efficiency is improved.

[0028] A supporting conductive component is also provided, and the supporting conductive component is partially attached to the side wall of the diaphragm 3 electrode component. The cathode frame and the cathode frame are provided with a fixing portion extending toward the supporting conductive component, and the top of the fixing portion on at least one side abuts the diaphragm 3 electrode component through the supporting conductive component. The fixing portion is, for example, a component formed in the cathode frame or the anode frame, and can be a conductive metal component or a non-conductive component. The supporting conductive component is, for example, a metal hollow material with elasticity. In an electrolytic cell with low pressure, the supporting conductive component is abutted by the fixing portion, so that the elastic force is evenly attached to one side or both sides of the diaphragm 3, so as to prevent the diaphragm 3 from shaking freely and being damaged under voltage fluctuations.

[0029] In one embodiment, the supporting conductive component includes: a buffer mesh 7 and a supporting mesh 6, wherein the buffer mesh 7 and the supporting mesh 6 are stacked, and the buffer mesh 7 is, for example, a corrugated spring, and the corrugated spring is wavy in the transverse direction, so that the top of the buffer mesh 7 and the pole mesh are evenly in contact in the length and width directions to prevent damage to the pole mesh at the corresponding position, and the top of the supporting conductive component abuts against the buffer mesh 7 through the supporting mesh 6, and elastically abuts against the cathode mesh 8 and / or one side of the anode mesh 4 through the buffer mesh 7, so that the diaphragm 3 is elastically pressed between the cathode mesh 8 and the anode mesh 4.

[0030] The supporting conductive component can be placed only in the anode cavity 1, or only in the cathode cavity 2, or in both the cathode cavity 2 and the anode cavity 1. The supporting mesh 6 is, for example, a lattice-shaped metal grid. The top of the supporting tube 5 in the cavity elastically squeezes the pole mesh on the corresponding side by abutting the supporting mesh 6. The concentrated surface-to-surface contact between the supporting tube 5 and the supporting mesh 6 is converted into multi-point dispersed contact between the buffer mesh 7 and the pole mesh through the supporting mesh 6 and the buffer mesh 7, so that the elastic squeezing force of the buffer mesh 7 on the pole mesh at various positions is evenly distributed, so that the pole meshes maintain a very small spacing. In the working power-on state, the spacing between the cathode mesh 8 and the anode mesh 4 is small, so that the resistance between the cathode mesh 8 and the anode mesh 4 is very small. When preparing the same amount of hydrogen, the power consumption between the cathode mesh 8 and the anode is reduced, and the efficiency of generating hydrogen is also improved.

[0031] In addition, in the energized state, the support net 6 and the buffer net 7 are energized to Figure 1 For example, the support mesh 6 and the buffer mesh 7 also form an electric field with the anode mesh 4 under the conductive effect of the cathode mesh 8, so that the free hydroxide ions or hydrogen ions are more easily combined with electrons to generate hydrogen under the action of the electric field because the support mesh 6 and the buffer mesh 7 provide a larger reaction area, thereby having a higher hydrogen reaction efficiency.

[0032] In a specific embodiment, the edges of the cathode mesh 8 and / or the anode mesh 4 are turned outward to cover the edges of the adjacent buffer mesh 7 and the support mesh 6. The edge of the cathode mesh is bent toward one side of the support tube 5. During assembly, the edge of the cathode mesh can wrap the edges of the buffer mesh 7 and the support mesh 6 to form a whole. There is no need to place the buffer mesh 7, the support mesh 6 and the cathode mesh in the cathode cavity 2 and the anode cavity 1 one by one, thereby reducing the assembly steps and improving the assembly efficiency.

[0033] More specifically, Figure 1 For example, in the anode chamber 1, the anode mesh 4 is welded to the bottom of the support tube 5, a partition 11 is welded to the top of the support tube 5, the pole frame 9 is welded to the end of the partition 11 away from the support tube 5, and a gasket 10 is connected to the other side of the pole frame 9 relative to the welding point of the pole frame 9 and the partition 11, and the top of at least part of the diaphragm 3 is elastically abutted by the gasket 10. During assembly, the anode mesh 4, the support tube 5 and the pole frame 9 are welded into one, wherein the anode mesh 4 is located in the anode chamber 1, and the length of the anode mesh 4 is shorter than the length of the diaphragm 3. In one embodiment of the anode chamber 1, in the cathode chamber 2, the edge of the cathode mesh 8 is turned outward to cover the edges of the adjacent buffer mesh 7 and the support mesh 6, the partition 11 is welded to the bottom of the support tube 5, and the pole frame 9 is welded by the partition 11, and the gasket 10 is bonded to the pole frame 9 near the edge, and the bottom of at least part of the diaphragm 3 is elastically abutted by the gasket 10. The gasket 10 is, for example, an EPDM rubber gasket or a PTEF gasket. The two pole frames 9 elastically squeeze the edge of the diaphragm 3 sandwiched in the middle through the gasket 10, which can clamp the diaphragm 3 while preventing the rigid pole frame 9 from directly squeezing the diaphragm 3 and causing damage, and also prevent liquid from leaking through the gap between the pole frame 9 and the diaphragm.

[0034] In another embodiment, after combination, the thickness of the gasket 10 is H, wherein H is, for example, 2.5 mm-3 mm. In a relaxed state, the height of the anode mesh 4 is lower than the thickness h1 of the gasket 10 located on the side close to the anode cavity 1, and the height of the cathode mesh 8 is higher than the thickness h2 of the gasket 10 located on the side close to the cathode cavity 2, wherein h1 is, for example, 0.5-0.6 mm, and h2 is, for example, 2.5-2.9 mm. The gasket 10 is compressed by 20%. After the gasket 10 is squeezed, the heights h1 and h2 will change with the compression of the buffer mesh 7, so that the gaskets 10 on both sides of the diaphragm 3 are flush with the surface heights of the cathode mesh 8 and the anode mesh 4, thereby reducing the resistance between the anode meshes and reducing power consumption.

[0035] In one embodiment, the compression amount of the buffer net 7 does not exceed 58% of the height of the buffer net 7 in a relaxed state. According to experimental tests, the buffer net 7 within this compression range can maintain good elasticity, so that the pole net and the diaphragm 3 attached through the pole net are elastically attached, and when the voltage between the anode net 4 and the cathode net 8 is unstable and causes the pressure difference in the cathode and cathode cavities to fluctuate, the flexible diaphragm 3 will not move with the push of the liquid because the pole net is elastically attached to it by the buffer net 7, thereby preventing the diaphragm 3 from being damaged.

[0036] More specifically, the cross-section of the fixed part is a trapezoid, and the fixed part is a tubular structure with a trapezoidal cross-section. The shorter upper base of the trapezoid serves as a supporting surface for the contact electrode network, which can reduce the consumption of electrical energy on the fixed part while ensuring that the fixed part also serves as a part of the electrode to generate an electric field to drive rapid ion exchange.

[0037] An electrolysis module, comprising a plurality of electrolytic cells, electrolytic cells and power supply devices as described above, wherein the electrolytic cells contain alkali solution, the cathode net 8, diaphragm 3 and anode net 4 of the electrolytic cells are placed in the alkali solution, and the power supply device is electrically connected to the cathode net 8 and the anode net 4 to provide electric energy to the electrolytic cells. The electrolytic cell contains a plurality of electrolytic cells arranged in parallel, and the power supply device is electrically connected to the electrolytic cells through a wire. Since the diaphragm 3 in a single electrolytic cell is elastically fitted between the buffer net 7 and the support net 6, the diaphragm 3 will not be damaged due to the pressure difference of the liquid, thereby ensuring good durability.

[0038] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, substitute and modify the above embodiments within the scope of the invention without departing from the principles and purpose of the present invention. All such changes should fall within the scope of protection of the claims of the present invention.

Claims

1. An electrolyzer for producing hydrogen by low-pressure water electrolysis, characterized in that: include: A cathode frame and an anode frame, wherein the cathode frame and the anode frame are separated by a diaphragm and are used to electrolyze alkaline solution to generate hydrogen in the cathode cavity of the cathode frame and oxygen in the anode cavity of the anode frame; A membrane electrode assembly, the membrane electrode assembly comprising a cathode mesh, a membrane and an anode mesh; A supporting conductive component is also provided, wherein the supporting conductive component is partially attached to the side wall of the diaphragm electrode component, the cathode frame and the cathode frame are provided with a fixing portion extending toward the supporting conductive component, and the top of the fixing portion on at least one side elastically abuts against the diaphragm electrode component through the supporting conductive component; The supporting conductive component comprises: a buffer net and a supporting net, wherein the buffer net and the supporting net are stacked, the top of the supporting conductive component abuts against the buffer net through the supporting net, and the buffer net elastically abuts against one side of the cathode net and / or the anode net, so that the diaphragm elastically abuts between the cathode net and the anode net; The edges of the cathode mesh and / or the anode mesh are turned outward to cover the edges of the adjacent buffer mesh and the support mesh; The cross section of the fixing portion is a trapezoid; In the anode chamber, the anode mesh is welded to the bottom of the support tube, a partition is welded to the top of the support tube, the pole frame is welded to the end of the partition away from the support tube, a gasket is connected to the other side of the pole frame relative to the welding point between the pole frame and the partition, and the gasket elastically seals and abuts against at least part of the top of the diaphragm; In the cathode cavity, the edge of the cathode net is turned outward to cover the edges of the adjacent buffer net and the support net, the partition is welded to the bottom of the support tube, and the pole frame is welded through the partition, a gasket is bonded to the pole frame near the edge, and the gasket is elastically sealed to abut at least part of the bottom of the diaphragm to fix the pole frame on the other side of the diaphragm.

2. The electrolytic cell according to claim 1, characterized in that After assembly, the thickness of the gasket is H. In a relaxed state, the height of the anode mesh is lower than the thickness h1 of the gasket located near the anode cavity, and the height of the cathode mesh is higher than the thickness h2 of the gasket located near the cathode cavity. The h1 is 0.5-0.6 mm, and the h2 is 2.5-2.9 mm.

3. The electrolytic cell according to claim 1, characterized in that The compression amount of the buffer net does not exceed 58% of the height of the buffer net in a relaxed state.

4. An electrolysis module, characterized in that: It comprises a plurality of electrolytic cells, electrolytic cells and power supply devices as described in any one of claims 1 to 3, wherein the electrolytic cells contain alkaline solution, the cathode network, diaphragm and anode network of the electrolytic cells are placed in the alkaline solution, and the power supply device is electrically connected to the cathode network and the anode network to provide electrical energy to the electrolytic cells.

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