Layer system for electrolyser

Abstract

The present disclosure relates to a layer system (1) for an electrolyser (100) and a corresponding electrolyser (100). The layer system (1) comprises a substrate layer stack (10) having the following layers in a given order: a first perforated layer (20) having a plurality of perforations (21a, 21b, 21c), a first bipolar layer (30), and a second perforated layer (40) having a plurality of perforations. The first bipolar layer (30) comprises first spacing means (32a, 32b, 32c) on the first surface (31) to space the first perforated layer (20) and the first bipolar layer (30) apart. Furthermore, the first bipolar layer (30) comprises second spacing means (34a, 34b, 34c) on a second surface (33) opposite the first surface (31) to space the second perforated layer (40) and the first bipolar layer (30).

Description

Technical Field

[0001] The present disclosure relates to a layer system for an electrolyser and to a corresponding electrolyser. Background Art

[0002] An electrolyzer is a device used to split water into its component parts (i.e., hydrogen and oxygen) through a process of electrolysis. The technology has been widely studied and implemented in a range of applications, including the production of hydrogen as a fuel, the generation of oxygen for medical and industrial purposes, and the removal of impurities from water.

[0003] In recent years, there has been growing interest in electrolyzers due to their potential to aid the transition to a more sustainable energy system. Electrolyzers can use renewable energy sources such as wind and solar to produce hydrogen, which can then be used as a clean and versatile energy carrier. In addition, electrolyzers can be used to store excess energy, allowing intermittent renewable energy sources to be integrated into the grid.

[0004] Despite these advantages, there are still challenges that need to be addressed. Especially when considering the design of the layer system of current electrolyzers. The layer system of an electrolyzer primarily determines how easy it is to manufacture, assemble and / or maintain the electrolyzer. Furthermore, the layer system is critical to the efficiency and durability of the electrolyzer.

[0005] However, existing layer systems are often difficult to manufacture, assemble and / or maintain, in particular due to the complex design of existing layer systems, which often involve a plurality of individual components. In addition, existing layer systems for electrolyzers are often material-intensive and therefore also expensive. In particular for layer systems for alkaline electrolyzers, as shown by way of example in EP 2862960 B1, it has been determined that a simplified layer system is needed.

[0006] It is therefore an object of the present disclosure to provide a layer system for an electrolyser and a corresponding electrolyser which at least partially overcome the aforementioned disadvantages. In particular, the present invention aims to provide a simpler layer system for an electrolyser, in particular an alkaline electrolyser. Summary of the invention

[0007] This object is at least partly achieved by a layer system for an electrolyser and a corresponding electrolyser as defined in the independent claims. Further aspects of the disclosure are defined in the dependent claims.

[0008] In particular, the object is achieved by a layer system for an electrolyser, wherein the layer system comprises a substrate layer stack having the following given order of layers: (i) a first perforated layer having a plurality of perforations; (ii) a first bipolar layer; and (iii) a second perforated layer having a plurality of perforations. The first bipolar layer comprises a first spacing means on a first surface to space the first perforated layer from the first bipolar layer. Furthermore, the first bipolar layer comprises a second spacing means on a second surface opposite to the first surface to space the second perforated layer from the first bipolar layer.

[0009] The first perforated layer may be configured as a cathode and / or an anode. In addition, the second perforated layer may also be configured as a cathode and / or an anode. It should be understood that when the first perforated layer is configured as an anode, the second perforated layer is configured as a cathode, and vice versa. The first perforated layer and / or the second perforated layer may have a thickness falling within the range of 0.3 mm to 1.5 mm, preferably 0.5 to 1 mm, and further preferably 0.7 mm to 0.8 mm. It has been shown that these thicknesses provide sufficient stability while avoiding excessive material.

[0010] The perforations of the first perforated layer and / or the second perforated layer may include circular through holes, rectangular through holes and / or through holes of any other shape. In addition, the perforations of the first perforated layer and / or the second perforated layer may be arranged in a regular pattern.

[0011] The first surface and / or the second surface of the first bipolar layer may be defined as the surface of the first bipolar layer adjacent to the respective spacer means. Exemplarily, if the first bipolar layer is a sheet metal and the first spacer means is a spherical element stamped into the sheet metal, the first surface may be defined as the undeformed surface adjacent to the stamped spherical element and facing the first perforated layer.

[0012] The layer system according to the present disclosure has various advantages compared to the prior art, two of which are explained below as examples.

[0013] Firstly, the spacer can be used to support the perforated layers against each other on the one hand and ensure that a volume is created between the perforated layers (e.g. to accommodate the electrolyte) on the other hand. Accordingly, the first bipolar layer integrates multiple functions, enabling a simple and compact configuration with fewer individual components. Thus, manufacturing, assembly and / or maintenance can be facilitated.

[0014] Secondly, the configuration of the layer system according to the present disclosure allows the layers of the substrate layer stack to be stacked on top of each other without an external frame and / or a retainer structure. In particular, due to the spacing device of the first bipolar layer. Exemplarily, the layers of the substrate layer stack can be stacked on top of each other, with only sealing elements and / or spacer elements arranged between the layers. Thus, the use of materials and / or separate components can be reduced compared to existing layer systems. Furthermore, assembly and maintenance can be particularly facilitated.

[0015] It should be understood that these advantages may also be applied below in different formulations, wherein additional advantages will become apparent when studying the following description.

[0016] Preferably, the first spacer is adjacent to the first perforated layer, and / or wherein the second spacer is adjacent to the second perforated layer. Thus, the bipolar layer can establish a reliable electrical contact between the first perforated layer and the second perforated layer.

[0017] The maximum height of the first spacer measured from the first surface of the first bipolar layer can correspond to the maximum height of the second spacer measured from the second surface of the first bipolar layer multiplied by a value falling within the range of 0.2 to 0.8, preferably 0.3 to 0.7, and further preferably 0.4 to 0.6. It has been shown that these ratios correspond at least partially to the ratios of oxygen and hydrogen during electrolysis. Accordingly, the design of the layer system can be made particularly compact. It will be appreciated that for the above-described configuration of the spacer, oxygen will be produced adjacent to the first surface of the first bipolar layer, wherein hydrogen will be produced adjacent to the second surface of the first bipolar layer.

[0018] The first spacer and / or the second spacer may each comprise a plurality of protrusions formed integrally with the first bipolar layer, wherein preferably, the plurality of protrusions comprise spherical segments, truncated cones, ribs and / or pins, wherein further preferably, the plurality of protrusions are arranged in a regular pattern, wherein further preferably, the plurality of protrusions form a flow channel along the first bipolar layer. In this regard, "integrally formed" may refer to the aspect that no material boundary can be identified between the spacer and the first bipolar layer. By forming the plurality of protrusions integrally with the first bipolar layer, assembly and / or manufacturing may be simplified. In addition, a particularly robust design may be achieved. Preferably, the first spacer and the second spacer each comprise at least one hundred protrusions. In a particular embodiment, the first bipolar layer is a sheet metal, wherein the protrusions are stamped into the sheet metal. Alternatively, the protrusions may be welded to the sheet metal.

[0019] The layer system can include a first circumferential gasket compressed between the first perforated layer and the first bipolar layer so that the space between these layers is laterally sealed, and / or a second circumferential gasket compressed between the second perforated layer and the first bipolar layer so that the space between these layers is laterally sealed. The space between the layers is laterally sealed so that the fluid can only be transmitted to the space between the layers via the perforations of the perforated layer and / or via the corresponding fluid inlet / outlet. In addition, the gasket is used to support the layers against each other of the layer system. Therefore, the first circumferential gasket and / or the second circumferential gasket can allow the layer configuration that does not require an additional supporting structure to support the layers against each other. Accordingly, the layer design can be particularly simple, thereby easy to manufacture and / or assemble. However, it should be understood that a device for compressing the layers against each other may be needed. Preferably, the first circumferential gasket and / or the second circumferential gasket include nitrile rubber, EPDM rubber, butyl rubber and / or fluororubber. It has been shown that these materials allow enough sealing on the one hand, and provide enough mechanical stability on the other hand to stably support the layers against each other of the layer system.

[0020] The first bipolar layer may have a thickness falling within the range of 1 mm to 2 mm, preferably 1.3 to 1.7 mm, and further preferably 1.4 mm to 1.6 mm. Preferably, the thickness is measured from the first surface of the first bipolar layer to the second surface of the first bipolar layer. It has been shown that these thicknesses provide sufficient stability while avoiding excess material and at the same time enhancing electrical performance.

[0021] The first perforated layer, the second perforated layer and / or the first bipolar layer are preferably made of sheet metal, respectively, wherein further preferably, the sheet metal is selected from nickel-plated carbon steel, stainless steel 316L, alloy 200, alloy 201, and / or alloy 59. By using sheet metal, simplified manufacturing can be achieved. Exemplarily, due to the efficient process of processing sheet metal. In addition, the mentioned materials have proven to be particularly advantageous in terms of their electrical and mechanical properties.

[0022] The first perforated layer and / or the second perforated layer can be coated by the electrodes and / or the first bipolar layer can be coated with nickel. It has been shown that this can achieve an improved performance of the layer system in the electrolyser.

[0023] Preferably, the first bipolar layer does not have a separate and / or circumferential metal frame attached thereto. In this regard, "separate" refers to the aspect that the frame is not formed integrally with the corresponding bipolar layer. Typically, the bipolar layer (particularly in the layer system of an alkaline electrolyzer) is provided with a separate and circumferential metal frame attached thereto for the purpose of stabilizing and / or separating. By providing a first bipolar layer without a separate and / or circumferential metal frame attached thereto, a simplified layer system can be achieved, making it less complicated to manufacture and / or assemble. It should be understood that several aspects described in the present disclosure can contribute to the fact that the frame is not needed. Particularly spacers and / or washers.

[0024] The first bipolar layer may include a first gas outlet connected to the first surface fluid of the bipolar layer, and a second gas outlet connected to the second surface fluid of the bipolar layer. Exemplarily, the gas outlets may both be through holes in the first bipolar layer. Thus, the circumferential gasket may ensure that the first gas outlet is only connected to the first surface fluid, and the second gas outlet is only connected to the second surface fluid.

[0025] The first bipolar layer, the first perforated layer and / or the second perforated layer may be substantially rectangular. It has been shown that a more efficient use of material is possible as a result. This is because the waste of the substrate material, which is usually provided in a roll, can be reduced.

[0026] The layer system may include two substrate layers stacked one on top of the other, with the membrane between two adjacent perforated layers. Preferably, the third circumferential gasket is also arranged between the two adjacent perforated layers, so that the space between these layers is laterally sealed. The third circumferential gasket is preferably configured so that only fluid transmission through adjacent perforated layers can be carried out via the membrane. The third circumferential gasket can also be used to stabilize the membrane between the perforated layers. By arranging the membrane between the two adjacent perforated layers, the membrane can approach the fluid adjacent to the perforated layer, and at the same time the membrane is stable between the perforated layers. Therefore, a compact layer system can be achieved. In a particularly preferred embodiment, the two adjacent perforated layers are laminated together by the third circumferential gasket as a rubber liner. Thereby two adjacent perforated layers can have substantially the same shape, which is further conducive to manufacturing and / or assembly. Further, in a particularly preferred embodiment, the membrane between the two adjacent perforated layers is an inlay.

[0027] The membrane may include (a) a nickel oxide membrane, (b) a solid polymer electrolyte (SPE) membrane, (c) a ceramic membrane, (d) an anion exchange membrane (AEM) which may be made of a material such as polyethylene, polypropylene and / or polyvinyl alcohol, (e) a cation exchange membrane (CEM) which may be made of perfluorosulfonic acid (PFSA) or polybenzimidazole (PBI), and / or (f) a composite membrane made by combining two or more types of membranes (e.g., SPE and AEM).

[0028] Furthermore, the object is achieved by an electrolyser comprising the layer system described herein, wherein the electrolyser is preferably an alkaline electrolyser, wherein further preferably the alkaline electrolyser comprises KOH or NaOH. It should be understood that the features and / or advantages described with respect to the layer system may also apply to the electrolyser. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Below, a brief description of the accompanying drawings is given:

[0030] Figure 1 A schematic layer system for an electrolyser according to the invention is shown in a side cross-sectional view;

[0031] Figure 2a In a top view an exemplary first bipolar layer according to the invention is shown;

[0032] Figure 2b In a top view an exemplary second bipolar layer according to the invention is shown;

[0033] Figure 3a An exemplary perforated layer according to the invention is shown in a top view;

[0034] Figure 3b Another exemplary perforated layer according to the invention is shown in a top view, and

[0035] Figure 4 A schematic electrolyser according to the invention with a layer system is shown in a side sectional view. DETAILED DESCRIPTION

[0036] Figure 1 An electrolyzer 100 (see Figure 4 ) of a layer system 1. The layer system 1 comprises a substrate layer stack 10 having layers in the following given order: (i) a first perforated layer 20 having a plurality of perforations 21a, 21b, 21c (see FIG. 3 ); (ii) a first bipolar layer 30, and (iii) a second perforated layer 40 having a plurality of perforations.

[0037] like Figure 1As further shown in FIG. 1 , the first bipolar layer 30 includes first spacers 32a, 32b on a first surface 31 to space the first perforated layer 20 from the first bipolar layer 30. The first spacers 32a, 32b are adjacent to the first perforated layer 20. In addition, the first bipolar layer 30 includes second spacers 34a, 34b on a second surface 33 opposite to the first surface 31 to space the second perforated layer 40 from the first bipolar layer 30. The second spacers 34a, 34b are adjacent to the second perforated layer 40. The maximum height of the first spacers 32a, 32b measured from the first surface 31 of the first bipolar layer 30 corresponds to the maximum height of the second spacers 34a, 34b measured from the second surface 33 of the first bipolar layer 30 multiplied by a value falling within the range of 0.3 to 0.7.

[0038] like Figure 1 , Figure 2a and Figure 2b As shown in FIG. 1 , the first spacers 32a, 32b, 32c and the second spacers 34a, 34b, 34c each include a plurality of protrusions formed integrally with the first bipolar layer 30. Figure 1 and Figure 2a The bipolar layer 30 includes a plurality of protrusions including spherical segments arranged in a regular pattern. Figure 2b The plurality of protrusions include rib shapes arranged in a regular pattern, wherein the ribs form flow channels along the first bipolar layer 30 .

[0039] In addition, if Figure 1 , Figure 2a and Figure 2b As depicted in , the first bipolar layer 30 does not have a separate and / or circumferential metal frame attached thereto.

[0040] In addition, Figure 1 , Figure 2a and Figure 2b As depicted in FIG, the layer system 1 comprises a first circumferential gasket 51 and a second circumferential gasket 52. The first circumferential gasket 51 is compressed between the first perforated layer 20 and the first bipolar layer 30, so that the space between these layers is laterally sealed. The second circumferential gasket 52 is compressed between the second perforated layer 40 and the first bipolar layer 30, so that the space between these layers is laterally sealed.

[0041] In addition, if Figure 2a and Figure 2bAs depicted in FIG. 1 , the first bipolar layer 30 includes a first gas outlet 35 fluidly connected to the first surface 31 of the first bipolar layer 30, and a second gas outlet 36 fluidly connected to the second surface 33 of the first bipolar layer 30 (not explicitly shown). Therefore, the gas (e.g., oxygen) between the first perforated layer 20 and the first bipolar layer 30 can only be discharged through the first gas outlet 35. In addition, the gas (e.g., hydrogen) between the second perforated layer 40 and the first bipolar layer 30 can only be discharged through the second gas outlet 36. It should be understood that additional openings located in the sealed area of ​​the first bipolar layer 30 can be used to introduce electrolyte.

[0042] like Figure 2a , Figure 2b , Figure 3a and Figure 3b As depicted in FIG. 1 , the first bipolar layer 30, the first perforated layer 20, and the second perforated layer 40 are substantially rectangular. Therefore, they can be stamped from sheet metal, thereby reducing waste.

[0043] Figure 4 The layer system 1 comprising the electrolyser 100 is shown. The layer system 1 comprises two substrate layer stacks 10 (as described above) stacked one on top of the other, with the membrane 60 between two adjacent perforated layers. It will be appreciated that the layer system 1 is compressed so that the spacer means of the substrate layer stack 10 abuts against adjacent perforated layers. Furthermore, between said two adjacent perforated layers where the membrane 60 is located, a third circumferential gasket 53 is arranged so that the space between these layers is laterally sealed. Figure 3a and Figure 3b , the third circumferential gasket 53 is configured so that fluid transfer through adjacent perforated layers can only be performed via the membrane 60. The circumferential gasket 53 also serves to stabilize the membrane 60 between the perforated layers by clamping the membrane 60. In a preferred embodiment, the two adjacent perforated layers are laminated together by means of the third circumferential gasket 53 as a rubber gasket, wherein the two adjacent perforated layers have substantially the same shape and the membrane 60 is an inlay.

[0044] like Figure 4 As further shown in FIG. 1 , the electrolyser 100 comprises a first plate 101 having an electrical contact device, and a second plate 102 having another electrical contact device. The first plate 101 and the second plate 102 are connected by screws (ie, screwed to each other) so that the layer system 1 between the two plates 101, 102 is compressed.

[0045] Reference numerals list

[0046] 1-tier system

[0047] 10 base layer stacking

[0048] 20First perforated layer

[0049] 21a, 21b, 21c perforation

[0050] 30 First bipolar layer

[0051] 31 First Surface

[0052] 32a, 32b, 32c first spacing device

[0053] 34a, 34b, 34c second spacer

[0054] 35 First gas outlet

[0055] 36 Second gas outlet

[0056] 40 Second perforated layer

[0057] 51 First circumferential gasket

[0058] 52 Second circumferential gasket

[0059] 53 Third circumferential gasket

[0060] 60 membrane

[0061] 100 electrolyzer

[0062] 101 First Board

[0063] 102 second plate.

Claims

1. A layer system (1) for an electrolyser (100), wherein: The layer system (1) comprises a substrate layer stack (10) having the following layers in the given order: A first perforated layer (20) having a plurality of perforations (21a, 21b, 21c); a first bipolar layer (30); as well as The second perforated layer (40) has a plurality of perforations, wherein the first bipolar layer (30) comprises a first spacer (32a, 32b, 32c) on a first surface (31) to separate the first perforated layer (20) from the first bipolar layer (30), and wherein the first bipolar layer (30) comprises a second spacer (34a, 34b, 34c) on a second surface (33) opposite to the first surface (31) to separate the second perforated layer (40) from the first bipolar layer (30).

2. Layer system (1) according to the preceding claim, wherein: The first spacer (32a, 32b, 32c) is adjacent to the first perforated layer (20), and / or wherein the second spacer (34a, 34b, 34c) is adjacent to the second perforated layer (40).

3. The layer system (1) according to any one of the preceding claims, wherein: The maximum height of the first spacer (32a, 32b, 32c) measured from the first surface (31) of the first bipolar layer (30) corresponds to the maximum height of the second spacer (34a, 34b, 34c) measured from the second surface (33) of the first bipolar layer (30) multiplied by a value falling within the range of 0.2 to 0.8, preferably 0.3 to 0.7, and further preferably 0.4 to 0.

6.

4. The layer system (1) according to any one of the preceding claims, wherein: The first spacer (32a, 32b, 32c) and / or the second spacer (34a, 34b, 34c) comprises a plurality of protrusions formed integrally with the first bipolar layer (30), wherein preferably, the protrusions comprise spherical segments, truncated cones, ribs and / or pins, wherein further preferably, the protrusions are arranged in a regular pattern, wherein further preferably, the protrusions form flow channels along the first bipolar layer (30).

5. The layer system (1) according to any one of the preceding claims, wherein: The layer system (1) comprises a first circumferential gasket (51) compressed between said first perforated layer (20) and said first bipolar layer (30) so that the space between these layers is laterally sealed, and / or A second circumferential gasket (52) is compressed between the second perforated layer (40) and the first bipolar layer (30) so that the space between these layers is laterally sealed.

6. The layer system (1) according to any one of the preceding claims, wherein: The first bipolar layer (30) has a thickness falling within the range of 1 mm to 2 mm, preferably 1.3 mm to 1.7 mm, and further preferably 1.4 mm to 1.6 mm.

7. The layer system (1) according to any one of the preceding claims, wherein: The first perforated layer (20), the second perforated layer (40) and / or the first bipolar layer (30) are respectively made of sheet metal, wherein preferably, the sheet metal is selected from nickel-plated carbon steel, stainless steel 316L, alloy 200, alloy 201 and / or alloy 59.

8. The layer system (1) according to any one of the preceding claims, wherein: The first perforated layer (20) and / or the second perforated layer (40) are electrode coated, and / or wherein the first bipolar layer (30) is nickel coated.

9. The layer system (1) according to any one of the preceding claims, wherein: The first bipolar layer (30) does not have a separate and / or circumferential metallic frame attached thereto.

10. The layer system (1) according to any one of the preceding claims, wherein: The first bipolar layer (30) includes a first gas outlet (35) fluidly connected to the first surface (31) of the first bipolar layer (30), and a second gas outlet (36) fluidly connected to the second surface (33) of the first bipolar layer (30).

11. The layer system (1) according to any one of the preceding claims, wherein: The first bipolar layer (30), the first perforated layer (20) and / or the second perforated layer (40) are substantially rectangular.

12. The layer system (1) according to any one of the preceding claims, wherein: The layer system (1) comprises two substrate layer stacks (10) placed one on top of the other, with a film (60) between two adjacent perforated layers.

13. Layer system (1) according to the preceding claim, wherein: The layer system (1) further comprises a third circumferential gasket (53) arranged between the two adjacent perforated layers so that the space between the layers is laterally sealed, wherein preferably, the two adjacent perforated layers are laminated together by means of the third circumferential gasket as a rubber gasket, wherein further preferably, the two adjacent perforated layers have substantially the same shape.

14. The layer system (1) according to claim 12, wherein: The membrane (60) may include a nickel oxide membrane, a solid polymer electrolyte membrane, a ceramic membrane, an anion exchange membrane, a cation exchange membrane and / or a composite membrane.

15. An electrolyser (100) comprising a layer system (1) according to any one of the preceding claims, wherein: The electrolyzer (100) is preferably an alkaline electrolyzer, wherein further preferably, the alkaline electrolyzer comprises KOH or NaOH.

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