An enhanced sealed proton exchange membrane water electrolysis hydrogen generation unit structure

Abstract

The application relates to a proton exchange membrane water electrolysis hydrogen production unit structure with enhanced sealing, which comprises an anode side sealing element, a cathode side sealing element, a cathode gas diffusion layer and a proton membrane; the anode side sealing element comprises a metal separator, an anode metal mesh, an anode side sealing gasket and an anode frame; the cathode side sealing element comprises a metal separator, a cathode side sealing gasket and a cathode frame; the proton membrane is clamped between the anode frame and the cathode frame; and the surfaces on both sides of the anode frame and the surfaces on both sides of the cathode frame are provided with multiple annular sealing convex ribs. Compared with the prior art, the application remarkably reduces the cost of sealing materials through improvement on the double-side frame structure, and effectively promotes the industrialization development of the PEM water electrolysis field.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of water electrolysis hydrogen production, in particular to a proton exchange membrane water electrolysis hydrogen production unit structure with enhanced sealing. BACKGROUND

[0002] Water electrolysis hydrogen production uses water as a reactant, and hydrogen and oxygen can be produced by applying direct current in an electrolysis device. The equipment is simple, and the produced hydrogen has high purity, which can be widely used in large-scale technology. There are three main ways of water electrolysis: alkaline water electrolysis hydrogen production, solid oxide water electrolysis hydrogen production, and proton exchange membrane water electrolysis hydrogen production. Among them, the proton exchange membrane water electrolysis hydrogen production has the characteristics of high current density, strong flexibility, high efficiency, and large energy capacity, which can well match renewable energy (such as wind energy and solar energy). In addition, due to the compact structure, it can operate at a high pressure of up to 350 bar, which is beneficial to the storage and transportation of hydrogen, and can effectively reduce the loss caused by compression and storage. The proton exchange membrane electrolysis cell (PEMEC) is mainly composed of a membrane electrode, a gas diffusion layer and a bipolar plate.

[0003] The membrane electrode, as the core component of the PEMEC, is mainly composed of an anode catalyst layer, a proton exchange membrane and a cathode catalyst layer. The anode catalyst mainly decomposes water into oxygen, electrons and protons; the proton exchange membrane acts as a solid electrolyte, which can effectively isolate the generated gas of the anode and the cathode, but the protons can pass through in the form of hydronium ions; the cathode catalyst promotes the reaction of hydrogen ions to generate hydrogen.

[0004] PEM hydrogen production requires high pressure (>2MPa) for the water electrolysis cell gas, which has very high requirements for sealing materials. There are few types of existing materials that meet the requirements, and the price is expensive, which restricts the cost and commercial application range of the water electrolysis cell. The cost of sealing structure and sealing material in PEM hydrogen production equipment is high, which limits the industrialization of this field. SUMMARY

[0005] The purpose of the present application is to overcome the defects of the prior art and provide a proton exchange membrane water electrolysis hydrogen production unit structure with enhanced sealing. Through the improvement of the double-side frame structure, the cost of sealing materials is significantly reduced, which effectively promotes the industrialization development of the PEM water electrolysis field.

[0006] The purpose of the present application can be achieved by the following technical solutions:

[0007] The purpose of the present application is to provide a proton exchange membrane water electrolysis hydrogen production unit structure with enhanced sealing, which comprises an anode side sealing element, a cathode side sealing element, a cathode gas diffusion layer and a proton membrane:

[0008] The anode side seal includes a metal partition plate, an anode side sealing gasket, and an anode frame;

[0009] The cathode side seal includes a metal partition plate, a cathode side sealing gasket, and a cathode frame.

[0010] The proton membrane is clamped between the anode frame and the cathode frame.

[0011] Both sides of the anode frame and the cathode frame are provided with multiple annular sealing ribs.

[0012] Each layer of the sealing structure is fixed by a bolt passing through a bolt mounting hole.

[0013] Further, one side of the anode frame is provided with a first anode frame sealing rib, which abuts against the surface of the anode side sealing gasket.

[0014] Further, the other side of the anode frame is provided with a second anode frame sealing rib, which abuts against the surface of the proton membrane.

[0015] Further, one side of the cathode frame is provided with a first cathode frame sealing rib, which abuts against the cathode side sealing gasket.

[0016] Further, one side of the cathode frame is provided with a second cathode frame sealing rib, which abuts against the surface of the proton membrane.

[0017] Further, the sealing rib is a flat rib with a circular arc chamfer or an arc top rib.

[0018] Further, the distance between the annular sealing ribs is equal, and the distance between the centers of adjacent ribs is 0.5-1.5 mm.

[0019] Further, the width and height of the annular sealing rib are equal, wherein the width is 0.1-0.4 mm and the height is 0.05-0.15 mm.

[0020] Further, the annular sealing ribs on the anode frame and the cathode frame are the same, and the center lines of the annular sealing ribs on all the anode frames and the cathode frames coincide.

[0021] Further, the materials of the anode frame and the cathode frame are selected from one of PSU, PPS, POM, and PA.

[0022] Compared with the prior art, the present application has the following technical advantages:

[0023] 1) The technical solution in this technical solution significantly enhances the sealing quality of PEM electrolytic water equipment through four side sealing protrusions on the two frames. The cathode frame sealing protrusion contacts the CCM and is supported by the anode frame sealing protrusion, thereby forming the sealing of the cathode side (hydrogen gas). In the compressed state, the anode side sealing protrusion contacts the anode sealing gasket and is supported by the anode metal separator, and the anode frame sealing protrusion 51 contacts the CCM and is supported by the cathode frame sealing protrusion, thereby forming the sealing of the anode side (oxygen and electrolytic water). Through the improvement of the double-sided frame structure, the cost of sealing materials is significantly reduced, and the industrialization development of PEM electrolytic water field is effectively promoted.

[0024] 2) Due to the sealing protrusions, the flatness and parallelism errors of the frame surface processing are compensated, the processing difficulty of the frame is reduced, and the production efficiency of the frame is improved.

[0025] 3) Due to the sealing protrusions of the frame, the thickness tolerance and assembly tolerance of the parts during assembly can be effectively compensated during the assembly of the electrolytic cell, thereby improving the assembly production efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figures 1-4 The figure is a schematic diagram of the proton exchange membrane electrolytic water hydrogen production unit structure in this technical solution to enhance the sealing.

[0027] Figure 5 The figure is a schematic diagram of the design of the cathode frame connecting channel and sealing protrusion in this technical solution.

[0028] Figures 6-8 The figure is a schematic diagram of the cross-sectional structure of the sealing protrusion in this technical solution.

[0029] In the figure: 10, metal separator, 20, cathode side sealing gasket, 30, cathode frame, 31, cathode frame connecting channel, 32, second cathode frame sealing protrusion, 33, first cathode frame sealing protrusion, 40, proton membrane, 50, anode frame, 51, second anode frame sealing protrusion, 60, anode side sealing gasket, 70, cathode side gas diffusion layer, 80, anode side metal mesh, 101, 102 hydrogen gas outlet; 103 electrolytic water inlet; 104 electrolytic water outlet; 105 bolt mounting hole; 106 voltage inspection tab. DETAILED DESCRIPTION

[0030] The invention will be described in detail below in conjunction with the drawings and specific examples. In this technical solution, the component model, material name, connection structure, control method, process step, etc. not explicitly described are considered as common technical features disclosed in the prior art.

[0031] As Figure 1 Figure 2 And Figure 3The figure shows a proton exchange membrane water electrolysis unit, in the bolted solid state, that is, the metal separator on both sides of the proton membrane is pressed tightly, the pressure is usually 900-1500 PSI, the electrolysis unit belongs to the components of the metal separator 10, the anode side sealing gasket 60, the anode sealing frame 50, the anode side metal mesh 80, the proton membrane (CCM) 40, the cathode side gas diffusion layer 70, the cathode frame 30, the cathode side sealing gasket 20.

[0032] In specific implementation, the anode side sealing member includes a metal separator, an anode side sealing gasket 60, and an anode frame 50; the cathode side sealing member includes a metal separator, a cathode side sealing gasket 20, and a cathode frame 30; the proton membrane 40 is clamped between the anode frame 50 and the cathode frame 30; the surfaces on both sides of the anode frame 50 and the surfaces on both sides of the cathode frame 30 are each provided with multiple annular sealing ribs. The layers of sealing structures are fixed by bolts passing through bolt mounting holes 105.

[0033] In specific implementation, one side of the anode frame 50 is provided with a first anode frame sealing rib 52, which abuts against the surface of the anode side sealing gasket 60. The other side of the anode frame 50 is provided with a second anode frame sealing rib 51, which abuts against the surface of the proton membrane 40. One side of the cathode frame 30 is provided with a first cathode frame sealing rib 33, which abuts against the cathode side sealing gasket 20. One side of the cathode frame 30 is provided with a second cathode frame sealing rib 32, which abuts against the surface of the proton membrane 40. Due to the provision of the sealing ribs, the errors in flatness and parallelism of the frame surface processing are compensated, the processing difficulty of the frame is reduced, and the production efficiency of the frame is improved. At the same time, due to the provision of the sealing ribs on the frame, the thickness tolerance and assembly tolerance of the parts during assembly can be effectively compensated during the assembly of the electrolysis cell, thereby improving the assembly production efficiency.

[0034] In specific implementation, as shown in the figure, Figure 3 Figure 4 The electrolysis water passes through the anode side electrolysis water inlet 103, fills the anode side cavity, and contacts the proton membrane. The metal separator on the right side of the proton membrane is connected to the negative electrode of the direct current power supply, and the metal separator on the left side of the proton membrane is connected to the positive electrode of the direct current power supply, and the voltage is usually about 1.5 V. The voltage detection is led out by the wire end 106 to the voltage detection equipment. At this time, hydrogen gas is generated on the cathode side of the membrane electrode, diffuses to the cathode side cavity through the gas diffusion layer, and is discharged through the hydrogen gas outlets 101 and 102 by the connection channel 31 of the cathode frame; oxygen is generated on the anode side of the membrane electrode, coexists with the electrolysis water, and is discharged through the outlet 104 by the connection channel of the anode frame.

[0035] In practical implementation, to ensure gas sealing on the cathode side and prevention of leakage of electrolyzed water and oxygen on the anode side during unit operation, sealing ridge structures numbered 32, 33, 51, and 52 are arranged on both sides of the cathode frame 30 and the anode frame 50, respectively. When the electrolysis unit is compressed, the cathode-side sealing ridge 33 contacts the cathode-side sealing gasket 20 and is supported by a metal partition; the cathode frame sealing ridge 32 contacts the CCM and is supported by the anode frame sealing ridge 51, thus forming a seal on the cathode side (hydrogen). In the compressed state, the anode-side sealing ridge 52 contacts the anode-side sealing gasket 60 and is supported by the anode-side metal partition; the anode frame sealing ridge 51 contacts the CCM and is supported by the cathode frame sealing ridge 32, thus forming a seal on the anode side (oxygen and electrolyzed water).

[0036] In specific implementation, such as Figure 5 The diagram shows the arrangement of the protruding ridges on the cathode frame. The positions and cross-sections of the protruding ridges on both sides of the frame are identical, and the center-to-center distance between adjacent ridges is 0.5mm to 1.5mm. The anode frame can utilize the cathode frame, rotating it 90° during assembly. Ensure that the centers of all protruding ridges on the cathode frame coincide with the centers of the protruding ridges on the anode frame to ensure tight contact during clamping.

[0037] When making a specific selection, such as Figure 6 The image shows a sealing ridge with a width K = 0.1–0.4 mm, an angle A = 10°–45°, a ridge height H = 0.05–0.15 mm, and a fillet R = 0.02–0.1 mm and a fillet r = 0.02–0.1 mm.

[0038] When selecting specific materials, the cathode frame and anode frame can be made of materials such as PSU (polysulfone resin), PPS, POM, PA, etc., and the processing technology is injection molding; the metal partition 10 is usually made of titanium (TA1 and TA2) and the surface coating is usually made of platinum.

[0039] Examples 2-3

[0040] Figure 7 and Figure 8 This is an extended example based on Example 1. The shape and structure of the sealing ridge have been adjusted in this example.

[0041] Figure 7 The cross-sectional shape of the central sealing ridge is a rounded rectangle. Figure 8 The sealing ridge has a circular arc shape. The width is selected from 0.1 to 0.4 mm, and the height of the ridge is selected from 0.05 to 0.15 mm.

[0042] The foregoing description of the embodiments has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the application to the precise form disclosed. Modifications and variations are possible in light of the above teachings or can be acquired from practice of the application. As well, the description is presented in the context of the preferred embodiments as a number of alternatives. It is not intended to limit the application to the precise form described.

Claims

1. An enhanced sealed proton exchange membrane water electrolysis hydrogen generation unit structure, characterized by, The sealing structure comprises an anode-side sealing member, a cathode-side sealing member, a cathode gas diffusion layer and a proton membrane (40); The anode-side sealing member comprises a metal separator, an anode-side sealing gasket (60) and an anode frame (50); The cathode-side sealing member comprises a metal separator, a cathode-side sealing gasket (20) and a cathode frame (30); The proton membrane (40) is sandwiched between the anode frame (50) and the cathode frame (30); Both sides of the anode frame (50) and both sides of the cathode frame (30) are provided with multiple annular sealing ribs; One side of the anode frame (50) is provided with a first anode frame sealing rib (52) which abuts against the surface of the anode-side sealing gasket (60); The other side of the anode frame (50) is provided with a second anode frame sealing rib (51) which abuts against the surface of the proton membrane (40); One side of the cathode frame (30) is provided with a first cathode frame sealing rib (33) which abuts against the cathode-side sealing gasket (20); The other side of the cathode frame (30) is provided with a second cathode frame sealing rib (32) which abuts against the surface of the proton membrane (40); The annular sealing ribs on the anode frame (50) and the cathode frame (30) are the same, and the center lines of the annular sealing ribs on all the anode frames (50) and the cathode frames (30) coincide.

2. The enhanced sealed proton exchange membrane water electrolysis unit structure of claim 1, wherein, The sealing rib is a flat rib with a circular arc chamfer or an arc top rib.

3. The enhanced sealed proton exchange membrane water electrolysis unit structure of claim 1, wherein, The distance between the annular sealing ribs of each ring is equal, and the distance between the centers of adjacent ribs is 0.5-1.5 mm.

4. The enhanced sealed proton exchange membrane water electrolysis unit structure of claim 1, wherein, The width and height of the annular sealing rib of each ring are equal, wherein the width is 0.1-0.1 mm and the height is 0.05-0.15 mm.

5. The enhanced sealed proton exchange membrane water electrolysis unit structure of claim 1, wherein, The materials of the anode frame (50) and the cathode frame (30) are selected from one of PSU, PPS, POM and PA.

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