Anion exchange membrane water electrolysis hydrogen production electrolytic bath

Abstract

The utility model relates to an anion exchange membrane water electrolysis hydrogen production electrolytic bath, which comprises a plurality of membrane electrode assemblies, a bipolar plate, collector plates on two sides, insulating spacers on two sides and end plates on two sides, and each membrane electrode assembly comprises an anion exchange membrane, a cathode and an anode. The anion exchange membrane water electrolysis hydrogen production electrolytic cell comprises a cathode and anode in-vitro gas-liquid circulation channel, and the cathode and anode in-vitro gas-liquid circulation channel comprises an electrolyte inlet main path, an electrolyte outlet main path, an oxygen outlet main path and a hydrogen outlet main path and is used for connecting liquid inlets or gas outlets corresponding to all small chambers in parallel through branches. And the adjacent small chambers near the flow fields on the two sides of the bipolar plate are completely isolated from each other in the lateral direction.

Description

Technical Field

[0001] The utility model relates to an electrolytic cell, in particular to an anion exchange membrane water electrolysis hydrogen production electrolytic cell. Background Art

[0002] Hydrogen is an ideal energy storage medium, boasting high energy density and being clean and pollution-free. Developing hydrogen energy is a key means of resolving the energy crisis and achieving carbon neutrality. In the future energy mix, hydrogen energy can be applied in a variety of fields, including metallurgy, steelmaking, and transportation. Using renewable energy to electrolyze water to produce green hydrogen not only addresses the challenges of renewable energy grid absorption and storage, but also addresses the source of green hydrogen. This development is considered a key pillar of the green, low-carbon transition to a green energy structure, drawing significant attention from various countries and becoming a key area of ​​international competition.

[0003] With the rapid development of the hydrogen energy industry, anion exchange membrane water electrolysis hydrogen production technology has gradually become a research focus in the hydrogen production field due to its significant advantages such as high current density, low cost, and the absence of precious metal catalysts. Currently, the mainstream anion exchange membrane water electrolysis hydrogen production electrolyzer on the market mainly consists of components such as membrane electrode assembly, metal bipolar plates, and sealing gaskets. The interaction of these components forms several electrolysis chambers within the anion exchange membrane water electrolysis hydrogen production electrolyzer, which also forms the liquid inlet and gas outlet channels for the anode and cathode regions. To ensure the safe and reliable operation of the electrolyzer, the hydrogen / oxygen inlet and outlet channels on the cathode and anode sides must be prevented from mixing, as mixing of hydrogen and oxygen is highly explosive. Furthermore, mixing of hydrogen and oxygen increases the cost of hydrogen or oxygen purification. Moreover, if the liquid inlet channels on the cathode and anode sides are connected, the electrolyzer cannot operate in dry cathode mode, affecting electrolysis efficiency. Therefore, the liquid inlet and gas outlet channel structures on the cathode and anode sides of each chamber will affect the overall performance of the electrolyzer and the cost of hydrogen production, and improving the liquid inlet and gas outlet channel structures becomes the key to designing anion exchange membrane water electrolysis hydrogen production electrolyzers.

[0004] Although the existing anion exchange membrane water electrolysis hydrogen production electrolyzer technology has achieved certain results in the field of hydrogen production, it still has the following shortcomings in practical application:

[0005] (1) Bipolar plate design issues: In existing anion exchange membrane water electrolysis hydrogen production electrolyzers, the bipolar plates are designed with sealing grooves and gas-liquid circulation channels. This design makes the bipolar plates difficult to process and assembly accuracy is difficult to ensure. In actual operation, the sealing performance between the bipolar plates, membrane electrode assembly, and sealing gasket is poor, resulting in easy mixing of the anode and cathode gases and liquids, affecting the normal operation of the electrolyzer and the purity of the hydrogen.

[0006] (2) Assembly precision: Due to the difficulty in machining the grooves and gas-liquid circulation channels on the bipolar plates, it is difficult to ensure assembly precision. During the operation of the electrolyzer, the assembly gaps between the components may cause gas-liquid leakage, further exacerbating the mixing of gas and liquid between the cathode and anode.

[0007] (3) Sealing performance issues: The sealing performance between the bipolar plate, membrane electrode assembly, and sealing gasket is a key factor affecting electrolyzer performance. In existing technologies, due to insufficient assembly precision, it is difficult to achieve ideal sealing performance, resulting in unstable electrolyzer operation and affecting hydrogen production and purity.

[0008] In summary, existing anion exchange membrane water electrolysis hydrogen production electrolyzer technology faces problems such as hydrogen-oxygen intermixing and poor sealing performance, which not only affect electrolysis efficiency but also pose safety risks. Therefore, technical improvements to address these issues are particularly urgent. This utility model aims to address these issues by proposing a novel anion exchange membrane water electrolysis hydrogen production electrolyzer design structure, hoping to provide strong support for the development of the hydrogen energy industry. Utility Model Content

[0009] In response to the problems of high bipolar plate processing costs, insufficient sealing performance, and the risk of hydrogen and oxygen mixing inside the cell body in existing anion exchange membrane water electrolysis hydrogen production electrolyzers, the purpose of this utility model is to provide an anion exchange membrane water electrolysis hydrogen production electrolyzer with simple process, reasonable structure, low manufacturing cost, energy saving and environmental protection. The technical solution of this utility model is:

[0010] An anion exchange membrane water electrolysis hydrogen production electrolyzer comprises a plurality of membrane electrode assemblies, bipolar plates, current collecting plates on both sides, insulating gaskets on both sides, and end plates on both sides. The membrane electrode assembly comprises an anion exchange membrane, a cathode, and an anode. The invention is characterized in that the anion exchange membrane water electrolysis hydrogen production electrolyzer comprises a gas-liquid circulation channel outside the anode and cathode electrodes. The gas-liquid circulation channel outside the anode and cathode electrodes comprises an electrolyte inlet main line, an electrolyte outlet main line, an oxygen outlet main line, and a hydrogen outlet main line, which are used to connect the corresponding liquid inlets or gas outlets of each chamber in parallel through branches, and the adjacent chambers near the flow fields on both sides of the bipolar plates are completely isolated laterally.

[0011] Furthermore, the gas-liquid circulation channel outside the anode and cathode electrodes includes several small chamber electrolyte inlet branches, electrolyte outlet branches, oxygen outlet branches, and hydrogen outlet branches respectively connected to each small chamber, and respectively connected in parallel to the corresponding electrolyte inlet main road, electrolyte outlet main road, oxygen outlet main road, and hydrogen outlet main road.

[0012] Furthermore, the anode and cathode external gas-liquid circulation channels include anode external gas-liquid circulation channels (9, 10, 11, 12) and cathode external gas-liquid circulation channels (17, 18, 19, 20), wherein the anode external gas-liquid circulation channels (9, 10, 11, 12) include a small chamber anode side electrolyte inlet branch (9), an electrolytic cell anode side electrolyte inlet main path (10), a plurality of small chamber anode side oxygen outlet branches (11), and an electrolytic cell anode side oxygen outlet main path (12), which are used to respectively transfer the oxygen from each small chamber to the outside of the electrolytic cell. The anode side liquid inlet and the anode side oxygen outlet of the chamber are connected in parallel to the corresponding main road through various branches; the cathode body gas-liquid circulation channel (17, 18, 19, 20) includes a plurality of small chamber cathode side electrolyte inlet branches (17), an electrolytic cell cathode side electrolyte inlet main road (18), a plurality of small chamber cathode side hydrogen outlet branches (19), and an electrolytic cell cathode side hydrogen outlet main road (20), and is used for connecting the small chamber cathode side liquid inlet and the small chamber cathode side hydrogen outlet of each small chamber in parallel to the corresponding main road through various branches outside the electrolytic cell.

[0013] Furthermore, when the cathode does not need to supply electrolyte, the electrolyte inlet main path (18) on the cathode side of the electrolytic cell is closed.

[0014] Furthermore, the gas-liquid circulation channels outside the anode and cathode electrodes adopt a quick-insert assembly structure for use under normal pressure conditions.

[0015] The anion exchange membrane water electrolysis hydrogen production electrolyzer of the present invention transfers the gas-liquid sealing problem that occurs directly inside the electrolyzer to the outside by setting an independent gas-liquid circulation channel outside the electrolyzer body, so that each small chamber has a relatively independent gas-liquid circulation cavity, and the gas-liquid communication between the small chambers is only carried out in the external channel, which can effectively isolate the gas and liquid of the cathode and anode, avoid the mixing of hydrogen and oxygen, and also avoid the accumulation of gas products inside the tank body, preventing the active sites or conductive interfaces on the electrodes from being blocked. Through this design, the overall performance and hydrogen production of the anion exchange membrane water electrolysis hydrogen production electrolyzer can be improved. The beneficial effects of the present utility model are:

[0016] 1) The present invention eliminates the interconnected liquid inlet and outlet structure between the bipolar plates and adopts a liquid inlet and outlet structure outside the electrolyzer body, avoiding the situation where multiple sets of bipolar plates are stacked to form multiple sealing surfaces, solving the problem of sealing between cells inside the anion exchange membrane electrolyzer, effectively preventing hydrogen and oxygen from mixing, reducing the risk of explosion, and improving safety.

[0017] 2) The present invention eliminates the interconnected liquid inlet and outlet structures between the bipolar plates and adopts a liquid inlet and outlet structure outside the electrolytic cell body, thereby avoiding the processing difficulties of traditional bipolar plates, sealing gasket channels and sealing surfaces, and also simplifies the precision requirements of the electrolytic cell bipolar plate stacking installation process, reducing the manufacturing costs of bipolar plates and sealing gaskets.

[0018] 2) The external liquid inlet and outlet structure of the electrolytic cell adopted in the present invention facilitates the inspection of leaks in the gas-liquid channel and also facilitates its repair, thereby reducing the maintenance cost of the electrolytic cell.

[0019] 3) The external liquid inlet and outlet structure of the electrolytic cell adopted in the present invention can isolate the fault in time by closing the branch of the gas-liquid circulation channel of the small chamber when a fault occurs in a small chamber (such as a perforation in the membrane, conduction between the positive and negative poles), avoiding the need to disassemble the cell body for major repairs, thereby extending the service life of the electrolytic cell.

[0020] 4) The extracorporeal liquid inlet and outlet structure of the electrolytic cell adopted in the present invention can be made into a more sealed whole-tube parallel anode and cathode extracorporeal gas-liquid circulation channel, which facilitates the electrolytic cell to produce high-pressure and high-purity hydrogen at a higher working pressure, reduces the cost of subsequent secondary pressurization and purification of hydrogen, and achieves the purpose of reducing production costs. At the same time, the high-pressure electrolytic cell can be suitable for a wider range of industrial application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings of the embodiments, but this is not intended to limit the present invention.

[0022] Figure 1 This is a front view of the utility model anion exchange membrane water electrolysis hydrogen production electrolyzer when the extracorporeal gas-liquid circulation channel is not installed;

[0023] Figure 2 This is a top view of the utility model anion exchange membrane water electrolysis hydrogen production electrolyzer when it is equipped with an anode side extracorporeal gas-liquid circulation channel;

[0024] Figure 3 This is a top view of the utility model anion exchange membrane water electrolysis hydrogen production electrolyzer when it is equipped with a cathode side extracorporeal gas-liquid circulation channel;

[0025] Figure 4 yes Figure 1 Schematic diagram of the composition of the membrane electrode assembly 7;

[0026] In the figure: 1. Left end plate; 2. Fastening bolts; 3. Spring washers and nuts; 4. Left insulating gasket; 5. Left current collecting plate; 6. Bipolar plate; 7. Membrane electrode assembly; 8. Oxygen outlet on the anode side of the chamber; 9. Electrolyte inlet branch on the anode side of the chamber; 10. Electrolyte inlet main line on the anode side of the electrolyzer; 11. Oxygen outlet branch on the anode side of the chamber; 12. Oxygen outlet main line on the anode side of the electrolyzer; 13. Right current collecting plate; 14. Right insulating gasket; 15. Right end plate; 16. Electrolyte inlet on the cathode side of the chamber; 17. Electrolyte inlet branch on the cathode side of the chamber; 18. Electrolyte inlet main line on the cathode side of the electrolyzer; 19. Hydrogen outlet branch on the cathode side of the chamber; 20. Hydrogen outlet main line on the cathode side of the electrolyzer; 7-1. Anion exchange membrane; 7-2. Anode; 7-3. Cathode; 7-4. Anode side sealing gasket; 7-5. Cathode side sealing gasket. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0028] The design method of this anion exchange membrane water electrolysis hydrogen production electrolyzer is that it designs the liquid inlet and outlet structure outside the traditional anion exchange membrane water electrolysis hydrogen production electrolyzer, avoiding the situation where multiple sets of bipolar plates are stacked to form multiple sealing surfaces, solving the problem of sealing between cells inside the anion exchange membrane electrolyzer, and at the same time achieving the purpose of simplifying the process and reducing manufacturing costs.

[0029] Example 1:

[0030] like Figure 1 、 Figure 2 and Figure 3 As shown, an anion exchange membrane water electrolysis hydrogen production electrolyzer includes a left end plate 1, a left insulating gasket 4, a left current collecting plate 5, a plurality of bipolar plates 6, a plurality of membrane electrode assemblies 7, a right current collecting plate 13, a right insulating gasket 14, a right end plate 15, a plurality of small chamber anode side electrolyte inlet branches 9, an electrolyzer anode side electrolyte inlet main line 10, a plurality of small chamber anode side oxygen outlet branches 11, an electrolyzer anode side oxygen outlet main line 12, a plurality of small chamber cathode side electrolyte inlet branches 17, an electrolyzer cathode side electrolyte inlet main line 18, a plurality of small chamber cathode side hydrogen outlet branches 19, an electrolyzer cathode side hydrogen outlet main line 20, etc.

[0031] The electrolytic cell is fixed between the left end plate 1 and the right end plate 15 by fastening bolts 2 and a plurality of spring washers / nuts 3. The surface of the fastening bolts 2 is provided with an alkali-resistant insulating heat shrink tube.

[0032] The left insulating gasket 4 is arranged between the left end plate 1 and the left current collecting plate 5. The same arrangement is also arranged on the right side of the electrolytic cell.

[0033] The surfaces of the left collecting plate 5 and the right collecting plate 13 are coated with a conductive coating and are resistant to strong alkali corrosion.

[0034] The bipolar plate 6 no longer has vertical through holes for liquid inlet / gas outlet between the small chambers used in traditional stacked electrolyzers, thereby structurally avoiding the occurrence of gas-liquid mixing between the small chambers.

[0035] The sealing gaskets 7-4 and 7-5 can be made of corrosion-resistant polytetrafluoroethylene, fluororubber or other materials or a combination of different materials. The sealing gaskets and the anion exchange membrane 7-1 can be used in combination to achieve isolation and sealing between the anode 7-2 and the cathode 7-3 in each chamber.

[0036] The anode body gas-liquid circulation channel (9, 10, 11, 12) is formed by connecting the liquid inlet and oxygen outlet of each chamber in parallel through a whole pipe outside the electrolyzer. It can be made by seamless steel pipe technology, so that the electrolyzer can safely produce hydrogen under high pressure conditions.

[0037] The same is true for the cathode external gas-liquid circulation channels (17, 18, 19, 20). When the cathode is not required to supply electrolyte, the electrolyte inlet main channel 18 on the cathode side of the electrolytic cell can be closed.

[0038] like Figure 4 As shown, Figure 1 The membrane electrode assembly 7 in the embodiment is composed of an anion exchange membrane 7-1, an anode 7-2, a cathode 7-3, an anode side sealing gasket 7-4 and a cathode side sealing gasket 7-5.

[0039] The electrodes (anode 7-2 and cathode 7-3) may be in the shape of a woven mesh, fiber felt, foam holes or flat plates. The electrodes (anode 7-2 and cathode 7-3) may also be electrodes with catalyst coatings.

[0040] Example 2:

[0041] Further illustrating the structure of Example 1, the anode and cathode extracorporeal gas-liquid circulation channels (9, 10, 11, 12, 17, 18, 19, 20) can be constructed as a single-piece steel pipe structure or as a quick-plug modular structure. However, this solution is not suitable for supplying high-pressure liquids or high flow rates, as it may cause leakage. However, this quick-plug modular extracorporeal gas-liquid circulation channel allows for easier installation and removal of the anion exchange membrane water electrolysis hydrogen production electrolyzer, making it suitable for use in atmospheric pressure environments where frequent installation and disassembly of the electrolyzer is required.

[0042] Example 3:

[0043] Further illustrating the above-described embodiment 1 or 2, the gaps between the mating surfaces of the bipolar plates 6 in each chamber can be sealed with a sealant. This solution can meet high-pressure sealing requirements and has strong applicability, meeting the pressure requirements of 3MPa, 5MPa, or even higher for various types of anion exchange membrane water electrolysis hydrogen production electrolyzers.

[0044] The anion exchange membrane water electrolysis hydrogen production electrolyzer and design method provided by this utility model not only improves the safety and efficiency of the electrolyzer, but also reduces manufacturing costs, and has great market potential. With the continued expansion of the hydrogen energy industry, this utility model is expected to play an important role in renewable energy electrolysis hydrogen production, energy storage, and other fields, promoting the further development of hydrogen energy technology.

Claims

1. An anion exchange membrane water electrolysis hydrogen production electrolyzer, comprising a plurality of membrane electrode assemblies, bipolar plates, two side current collecting plates, two side insulating gaskets, and two side end plates, wherein the membrane electrode assembly comprises an anion exchange membrane, a cathode and an anode, characterized in that: The anion exchange membrane water electrolysis hydrogen production electrolyzer includes a gas-liquid circulation channel outside the anode and cathode electrodes, and the gas-liquid circulation channel outside the anode and cathode electrodes includes an electrolyte inlet main line, an electrolyte outlet main line, an oxygen outlet main line, and a hydrogen outlet main line, which are used to connect the corresponding liquid inlets or gas outlets of each chamber in parallel through branches, and the adjacent chambers near the flow fields on both sides of the bipolar plate are completely isolated from each other laterally.

2. The anion exchange membrane water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The gas-liquid circulation channel outside the anode and cathode electrodes includes several small chamber electrolyte inlet branches, electrolyte outlet branches, oxygen outlet branches, and hydrogen outlet branches that are respectively connected to each small chamber, and are respectively connected in parallel to the corresponding electrolyte inlet main road, electrolyte outlet main road, oxygen outlet main road, and hydrogen outlet main road.

3. The anion exchange membrane water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The anode and cathode external gas-liquid circulation channels include an anode external gas-liquid circulation channel and a cathode external gas-liquid circulation channel, wherein the anode external gas-liquid circulation channel includes a chamber anode side electrolyte inlet branch (9), an electrolytic cell anode side electrolyte inlet main path (10), a plurality of chamber anode side oxygen outlet branches (11), and an electrolytic cell anode side oxygen outlet main path (12), and is used to connect the anode side liquid inlet and the anode side oxygen outlet of each chamber in parallel to the corresponding main path through each branch outside the electrolytic cell; the cathode external gas-liquid circulation channel includes a plurality of chamber cathode side electrolyte inlet branches (17), an electrolytic cell cathode side electrolyte inlet main path (18), a plurality of chamber cathode side hydrogen outlet branches (19), and an electrolytic cell cathode side hydrogen outlet main path (20), and is used to connect the chamber cathode side liquid inlet and the chamber cathode side hydrogen outlet of each chamber in parallel to the corresponding main path through each branch outside the electrolytic cell.

4. The anion exchange membrane water electrolysis hydrogen production electrolyzer according to claim 3, characterized in that: The gas-liquid circulation channel outside the body of the positive and negative electrodes adopts a quick-insert combined structure and is used under normal pressure.

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