Electrode assembly for alkaline electrolytic cell
By pre-combining the cathode, diaphragm, and anode into an integrated electrode structure in an alkaline electrolytic cell, the problem of zero-distance contact between the anode, cathode, and diaphragm is solved, thereby improving electrolysis efficiency and reducing electrolysis energy consumption.
Patent Information
- Application Number
- CN202423126160.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2026-03-03
- Estimated Expiration
- 2034-12-18
AI Technical Summary
In existing alkaline electrolyzers, the anode and cathode cannot achieve true zero-distance contact with the diaphragm, resulting in low electrolysis efficiency and hydrogen production efficiency. Existing solutions are also costly and lack reliability.
The cathode, diaphragm, and anode are pre-bonded into an integrated electrode structure by lamination, adhesive bonding, or winding, forming a "sandwich" structure of cathode-diaphragm-anode. This ensures zero-distance contact between the electrode and the diaphragm, and enhances mechanical properties through metal fibers and PPS diaphragms.
This achieves true zero-distance contact between the electrodes and the diaphragm, reducing assembly difficulty and energy consumption in water electrolysis, while improving current efficiency and the overall performance of the electrolyzer.
Smart Images
Figure CN223963583U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a device for producing hydrogen by electrolysis of water, and in particular to an electrode assembly for an alkaline electrolyzer. Background Technology
[0002] Electrodes in alkaline electrolyzers are key components in the alkaline water electrolysis process for hydrogen production. Their structural design and material selection have a crucial impact on electrolysis efficiency and the overall performance of the system. PEM electrode structures typically consist of three parts: a proton exchange membrane, an anode, and a cathode, forming a so-called "three-in-one structure." Zero-gap electrode structures refer to electrolyzers where, through special design and technology, the distance between the cathode and anode is minimized, even reaching a state of "zero gap." This structure significantly reduces voltage loss in the electrolyzer, improves current efficiency, and thus increases hydrogen production yield and efficiency.
[0003] In traditional electrolyzer structures, gaps exist between the cathode, anode, and diaphragm due to machining and process errors in the gaskets, electrode frames, and nipple plates. Furthermore, in alkaline electrolyzers, the electrodes (including cathodes and anodes) and diaphragm exhibit a certain degree of bending in a vertical position, preventing true zero-gap contact. For nipple plate electrolyzers, zero-gap contact is achieved by point-to-point mounting of the nipple plates to bring the cathode or anode as close to the diaphragm as possible. However, in large-format electrolyzers, the electrodes are generally soft, and the presence of gaskets makes achieving ideal zero-gap contact nearly impossible. Similarly, alkaline electrolyzers with plate-mesh structures also cannot achieve zero-gap contact due to insufficient electrode support. This non-zero-gap condition significantly increases the electrolysis efficiency and hydrogen production efficiency of the electrolyzer.
[0004] In existing technologies, elastomers or nickel foam are commonly used to ensure good contact between the anode, cathode, and diaphragm. The elastomer approach involves adding a double layer of elastic nickel wire mesh (wave-shaped / spring-shaped) to the traditional electrode design, relying on the elastomer's elasticity to achieve zero gap between the anode, cathode, and diaphragm. However, the elastomer and anode require edge sealing, which is complex, expensive, and unsuitable for nipple plate structures. The nickel foam approach also provides elasticity, but long-term operation at high current densities may lead to degradation of the nickel foam's pore structure, resulting in insufficient reliability over extended periods, and even localized disintegration or breakage. It also suffers from high flow resistance, and the electrode structure is not reusable after installation. In actual operation, the nickel foam may degrade due to electrochemical oxidation or impurities in the electrolyte under the electrode reaction environment, affecting its service life. Summary of the Invention
[0005] Purpose of the utility model: The purpose of this utility model is to provide an electrode assembly for an alkaline electrolytic cell that features zero electrode spacing, improved current efficiency, reduced assembly difficulty, and reduced energy consumption in alkaline electrolysis.
[0006] Technical solution: The electrode assembly for the alkaline electrolytic cell of this utility model includes a cathode electrode, a diaphragm and an anode electrode connected in sequence by lamination.
[0007] Preferably, the thickness of the diaphragm is greater than the sum of the thicknesses of the two electrodes.
[0008] Preferably, the cathode electrode and the anode electrode are metal fiber electrodes.
[0009] Preferably, the diaphragm is a PPS diaphragm with added metal fibers.
[0010] Preferably, the metal is nickel or cobalt.
[0011] The electrode assembly for the alkaline electrolytic cell described in this utility model includes a cathode electrode, a PPS diaphragm, and an anode electrode connected in sequence. The cathode electrode and the PPS diaphragm, as well as the anode electrode and the PPS diaphragm, are fixed together by winding PPS wires on the PPS diaphragm.
[0012] Preferably, the thickness of the PPS diaphragm is greater than the sum of the thicknesses of the two electrodes.
[0013] Preferably, the PPS diaphragm contains metal fibers.
[0014] Preferably, the cathode electrode and the anode electrode are metal fiber electrodes.
[0015] Preferably, the metal is nickel or cobalt, and more preferably nickel.
[0016] The electrode assembly for an alkaline electrolytic cell described in this invention includes a cathode electrode, a diaphragm, and an anode electrode connected in sequence by adhesive bonding.
[0017] Preferably, the thickness of the diaphragm is greater than the sum of the thicknesses of the two electrodes.
[0018] Preferably, the cathode electrode and the anode electrode are metal fiber electrodes.
[0019] Preferably, the diaphragm is a PPS diaphragm with added metal fibers.
[0020] Preferably, the metal is nickel or cobalt.
[0021] Beneficial effects: Compared with the prior art, this utility model has the following advantages: (1) The electrode assembly combines the cathode, diaphragm and anode into an integrated electrode structure in advance through physical means, so that the electrode and diaphragm can achieve true zero-gap contact; (2) The electrode assembly combines the cathode, diaphragm and anode into an integrated electrode structure in advance through physical means, which is simple to process and saves costs; (3) In the early stage of assembly, the anode and cathode are fixed together with the diaphragm in advance by lamination, adhesive bonding or physical winding to form a "sandwich" structure of cathode-diaphragm-anode, which can not only form a zero-gap electrode structure, but also greatly reduce the assembly difficulty and effectively reduce the energy consumption of water electrolysis. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the overall appearance of Example 1;
[0023] Figure 2 This is a schematic diagram of the overall appearance of Example 2;
[0024] Figure 3 This is an exploded view of the electrolysis chamber containing the electrode assembly described in this invention. Detailed Implementation
[0025] The technical solution of this utility model will be further described below with reference to the embodiments.
[0026] Example 1
[0027] like Figure 1 As shown, the electrode assembly for the alkaline electrolytic cell of this utility model includes a cathode electrode 1, a diaphragm 2, and an anode electrode 3 connected in sequence by lamination.
[0028] The cathode electrode 1 and the anode electrode 3 are nickel wire fiber electrodes.
[0029] Membrane 2 is a PPS membrane, which has good gas barrier properties and ion permeability, but no electron permeability.
[0030] The diaphragm 2 is a PPS diaphragm with added metal fibers to enhance its mechanical properties and impact resistance.
[0031] The thickness of the diaphragm 2 is greater than the sum of the thicknesses of the cathode electrode 1 and the anode electrode 3, in order to avoid direct contact within the electrode structure and thus prevent short circuits.
[0032] In the initial stage of assembly, the cathode electrode, diaphragm, and anode electrode are assembled into one unit by lamination, forming a "sandwich" structure of cathode-diaphragm-anode. This structure not only forms a zero-gap electrode structure, but also greatly reduces the difficulty of later assembly and effectively reduces the energy consumption of water electrolysis.
[0033] like Figure 3 As shown, the electrode structure is assembled into the electrolytic cell as follows: the integrated zero-gap electrode assembly 6 is installed between two electrode plates 7, and a gasket 8 is installed between the electrode assembly 6 and one of the electrode plates 7. Since the electrode and the diaphragm are fixed together during the manufacturing process, the electrolytic cells can be stacked layer by layer during the installation of the entire electrolytic cell, greatly reducing the installation difficulty and providing significant advantages for the sealing and positioning of the electrolytic cell.
[0034] Example 2
[0035] like Figure 2 As shown, the similarities between this embodiment and Embodiment 1 will not be repeated. The difference lies in that the electrode assembly includes a cathode electrode 1, a PPS diaphragm 5, and an anode electrode 3 connected in sequence. The cathode electrode 1 and the PPS diaphragm 5, as well as the anode electrode 3 and the PPS diaphragm 5, are fixed together by winding PPS threads 4 on the PPS diaphragm 5. Since the PPS diaphragm itself is woven from PPS threads, it is directly wound and fixed to the nickel wire electrode through the PPS threads at the edge of the PPS cloth, forming a "sandwich" structure of cathode-diaphragm-anode. This structure can greatly reduce the difficulty of subsequent assembly and can also form a zero-gap electrode structure, effectively reducing the energy consumption of water electrolysis.
[0036] Example 3
[0037] The similarities between this embodiment and Embodiment 1 will not be repeated here. The difference is that the electrode assembly includes a cathode electrode 1, a diaphragm 2, and an anode electrode 3 connected in sequence by adhesive bonding.
Claims
1. An electrode assembly for an alkaline electrolytic cell, characterized in that, The cathode electrode (1), PPS diaphragm (5) and anode electrode (3) are connected in sequence. The cathode electrode (1) and PPS diaphragm (5) and the anode electrode (3) and PPS diaphragm (5) are fixed by wrapping PPS wire (4) on the PPS diaphragm (5).
2. The electrode assembly for an alkaline electrolytic cell according to claim 1, characterized in that, The thickness of the PPS diaphragm (5) is greater than the sum of the thicknesses of the two electrodes.
3. The electrode assembly for an alkaline electrolytic cell according to claim 1, characterized in that, The cathode electrode (1) and anode electrode (3) are metal fiber electrodes, and the PPS diaphragm (5) contains metal fibers, wherein the metal is nickel or cobalt.