Method for producing electrodes

Abstract

The invention relates to a method for producing electrodes (1), the method comprising the steps of: rolling (10) a sheet of metal to provide a substrate (2); surface modifying (30) the substrate (2); applying (50) a catalyst material to the substrate (2) to produce a coating (5) comprising the catalyst material; and machining (70) the substrate (2) provided with the coating (5) to make the substrate (2) provided with the coating (5) permeable to a fluid.

Description

[0001] Process for the production of electrodes

[0002] The invention relates to a method for producing electrodes with a coating comprising a catalyst material and having fluid permeability. The invention further relates to a system for producing electrodes. The invention further relates to an electrode.

[0003] It is known to produce electrodes that are permeable to fluids. Perforated sheets, meshes, foams, or other porous substrates can be coated with catalyst material, resulting in fluid permeability after coating. Such electrodes are used, for example, in fuel cells and electrolyzers. The known manufacturing processes are expensive and do not allow for satisfactory production speeds.

[0004] The aim is to find solutions that will lead to increased electrode production rates and, in particular, to more efficient electrodes with lower catalyst material consumption. In particular, the disadvantages of the state of the art are to be avoided or at least significantly reduced.

[0005] The problem is solved by the features of the independent claims. Preferred embodiments are specified in the subclaims, the drawings, and the description, each of which, individually or in combination, may represent an aspect of the invention.

[0006] A method for producing electrodes is proposed, comprising the steps

[0007] Unrolling a sheet to provide a substrate, surface modification of the substrate,

[0008] Applying a catalyst material to the substrate to produce a coating comprising the catalyst material, and processing the substrate provided with the coating to produce a permeability of the substrate provided with the coating to a fluid.

[0009] In particular, the processing comprises a forming step, wherein the forming step is intended to produce the permeability of the substrate provided with the coating to a fluid.

[0010] Alternatively or additionally, the processing may comprise laser cutting or laser beam cutting, water jet cutting and / or etching of the substrate provided with the coating, in particular for producing a permeability of the substrate provided with the coating for a fluid.

[0011] In other words, a manufacturing method is specified in which a sheet metal material is unrolled. A surface layer of the sheet metal material is modified, for example, removed, altered, and / or applied. Catalyst material is applied to the sheet metal material to form the coating. Furthermore, the coated sheet metal material is processed at least in sections, e.g., plastically deformed or shaped and / or thermally processed and / or ablated using a laser or plasma, so that it becomes permeable to liquids or gases and / or porous.

[0012] The invention implements the idea that sheet metal can become porous or "leaky" when it is processed, e.g. deformed or formed and / or processed by laser, plasma, water jet or an etching medium. The processing comprises in particular mechanical and / or physical and / or chemical processing processes. However, the sheet metal is not necessarily deformed or processed by laser or plasma before coating or application of the catalyst material, as is known from the prior art, but after coating. This has the particular advantage of enabling a surprisingly inexpensive manufacturing process. Continuous coating processes, for example roll-to-roll and air-to-air processes, can be used very well. The sheet metal can then be unrolled and coated at different points on the sheet simultaneously, without individual pieces of sheet metal having to be handled.

[0013] Due to the proposed process, including surface modification or modification of a surface layer, the layer adhesion to the substrate is particularly good, which is why the processing surprisingly does not lead to delamination or only to an insignificant extent.

[0014] Another particular advantage is that no porous or leaky sheet is coated, preventing catalyst material from penetrating the small passages from one sheet side to the next. Rather, the porosity or leakage is created after coating with existing catalyst material, so that, among other things, a reduction in the cross-sectional area of ​​the passages tends to be avoided. The electrode becomes significantly more efficient, its cost-effectiveness increases, and the material required for coating is reduced.

[0015] Thanks to the invention, comparatively little catalyst material is coated. Significantly less material is lost, or less material is used that does not form the actual coating, compared to coating substrates that already exhibit permeability.

[0016] Preferred details and developments of the invention are presented below, which lead to further improvements, in particular of the advantages mentioned above.

[0017] In particular, the sheet metal is provided rolled up on a roll. The sheet metal can also be referred to as strip material. The sheet metal can be unwound from the roll to form the substrate. For example, the sheet metal is unwound along a substrate and / or extending substantially horizontally to undergo the process successively and in particular with the orientation of the sheet metal transverse to gravity. For example, the sheet metal is provided as endless material, in particular to undergo the process continuously. Endless material is to be understood as meaning that at least 10 meters or 20 meters of sheet metal are present in one piece, in particular wherein the piece of sheet metal can be present in one piece, starting from the unrolled state as an uncoated substrate to the state as a coated substrate that has been processed, e.g. formed and / or processed by means of a laser and / or by means of plasma and / or by means of a water jet and / or by means of etching.

[0018] The surface layer is in particular an oxide layer and / or a native passivation layer. In principle, the surface layer can be understood as the uppermost material layer of the freshly unrolled sheet, on which the sheet or then the substrate is to be coated. The surface layer is usually at least 1 nm and / or up to 1000 nm thick or even thicker, particularly in the case of metal sheets. Surface modification includes in particular mechanical, physical and / or chemical processes, e.g. to ablate and / or remove and / or apply and / or roughen and / or change the surface layer from the substrate. Examples of possible processes include plasma etching, blasting or grinding.

[0019] The catalyst material may, for example, comprise a metal, an oxide, and / or a nitride, in particular two or more of these and / or combinations thereof. The catalyst materials are proposed to be selected with a view to their intended use in fuel cells or electrolyzers.

[0020] Forming is understood, in particular, to mean plastic deformation and / or a forming process. When a metal is formed, it can also be said that it is bent or that a plastic deformation is carried out. The microstructure of the formed material or substrate can change. In particular, the forming or reshaping can change the thickness and / or strength of the substrate at the material sections that are formed. In light of the disclosure, it should be understood that machining processes also have an aspect of forming or reshaping because the material is reshaped during separation. In particular, material deformations are to be referred to as forming, which the invention intends to make advantageous use of.

[0021] Laser cutting, also known as laser material processing, refers in particular to material processing, such as separating and / or ablation, using laser technology. During laser cutting, through-holes can be machined or drilled into the substrate. Laser cutting can locally ablate material to create permeability. During laser cutting, laser radiation parameters such as wavelength, average power, pulse energy, and / or pulse duration can be adjusted. A primarily thermal ablation mechanism and thermal effects in the material (e.g., hardening of surrounding material) are essentially determined by the pulse duration and irradiance. Possible options include CO2 laser sources or Nd:YAG laser sources.

[0022] Plasma cutting, also known as plasma-assisted material processing, is a material processing process in which material can be removed and / or separated using a plasma and thermal energy. Plasma cutting can involve an arc between electrodes or anode and cathode (referred to as "transferred arc" or "direct plasma cutting") or an arc between a cathode as one electrode or cathode and a nozzle as the other electrode or anode (referred to as "non-transferred arc" or "indirect plasma cutting"). An auxiliary or sacrificial anode, such as a consumable wire, can also be provided. Plasma cutting can create passages in the substrate through thermal material removal, creating permeability.

[0023] Immediately after unrolling, the sheet or substrate is typically impermeable to a fluid. For example, if the substrate is stretched uniaxially or biaxially along its extension direction(s), pores and / or passages may form in the substrate and also in the coating. Permeability can be provided in this way. Permeability can also be created by introducing passages, for example, by perforating the coated substrate with pointed tools, such as a perforating roller. Alternatively or additionally, the substrate can also be provided with passages in an embossing or punching process.

[0024] Forming may primarily involve no material removal from the substrate and / or coating, or no such removal is intended. Forming may also involve material removal from the substrate and / or coating, for example, by making cutouts and / or removing material; however, even in this case, a deformation is likely to have occurred at the cut edge, which is regularly evident in the manufactured electrode, for example, in residual compressive stresses and / or surface hardening.

[0025] Laser cutting and / or plasma cutting typically involves removing material, for example, from the substrate and / or coating. This removal can be used to create permeability, for example, by creating fine channels from side to side of the substrate.

[0026] Fluid permeability means that the substrate is "leakage" across its extension or thickness, specifically with respect to a liquid and / or a gas. Thus, with regard to the potential application of the electrode in question, an electrolyte (a liquid) can penetrate through the electrode and / or hydrogen gas or other process gases, for example, from electrolysis, can penetrate through it.

[0027] The permeability of the substrate provided with the coating refers in particular to the property of being able to allow a fluid to pass through from flat side to flat side or in the thickness direction of the substrate. The permeable substrate can allow a fluid to pass through transversely to its direction of extension or is permeable to a fluid. In particular, the permeable substrate does not have gas distribution structures in its longitudinal directions, but can allow a fluid to pass through or be permeable to a fluid transversely to its direction of extension.

[0028] The sheet metal is preferably unwound or uncoiled at a speed of at least 0.5 m / min and / or at most 30 m / min. The strip speed is observed along the strip or substrate and is recorded in particular relative to the substrate and / or a coating system, in particular a vapor deposition, PVD and / or CVD system. The strip speed is preferably at least 1 m / min or at least 2 m / min and / or at most 20 m / min or at most 10 m / min. A strip speed of 5 m / min ± 2 m / min or even 3.5 m / min ± 2 m / min is particularly preferred. The strip speed is preferably maintained constant during the process in order to ensure that all steps are carried out reliably. This makes it possible to achieve a sufficient layer thickness and to enable adequate pre-cleaning or sufficiently good surface modification.

[0029] It is preferably provided that the processing, in particular the forming, comprises stretching, rolling, perforating, structuring and / or punching. The processing can comprise cutting or separating. The laser cutting and / or plasma cutting and / or waterjet cutting and / or etching preferably comprises material removal from the substrate, intermediate layer and / or coating. The waterjet cutting, laser cutting and / or plasma cutting preferably comprises compacting, roughening, hardening and / or heat treatment of the substrate, the intermediate layer and / or the coating. It is possible that a reaction zone is formed at a cut edge of the substrate produced by the processing, which reaction zone can have passivating and / or corrosion-inhibiting properties. In this way, the cut edge is passivated and the layer adhesion is improved.

[0030] It is possible for the method, preferably the processing or forming, in particular the perforating, to comprise the introduction of one or more passes, wherein the substrate is perforated with a pointed tool or with several pointed tools and / or with a perforating roller, in particular during punching and / or rolling. For example, the pointed tool can be pressed into the substrate provided with the coating in reciprocating movements and / or by rolling, preferably by being pressed through the substrate, so that the passage remains in particular as a perforation. To create the passage, a process such as needle rolling or needle tools can be used. A fluid can be allowed to pass through or flow through the passage transversely to the extent of the substrate provided with the coating.

[0031] The pointed tool can be in the form of a sharp-edged projection made of metal, preferably hard metal and / or steel, e.g. tool steel, in particular coated metal. The pointed tool can be arranged on a roller, in particular a perforating roller, which rolls over the substrate, in particular in order to penetrate the substrate with the pointed tool or to locally separate and reshape it and thus perforate it. The pointed tool can penetrate the substrate for perforation in a lifting movement oriented essentially transversely to the substrate; the lifting movement can be repeated at different points in order to perforate the surface. It is possible to provide a roller or a lifting tool with a plurality of pointed tools in order to increase productivity. By using the pointed tool, the coating can be applied adjacent to the point of penetration of the pointed tool orbe microscopically torn open adjacent to the introduced passage so that a surface of the catalyst material can be enlarged.

[0032] Preferably, the size or diameter of the passage along the substrate is at least 100 nm, or at least 500 nm, or at least 1 pm, or at least 10 pm, or at least 100 pm, or at least 1 mm. Preferably, the size or diameter of the passage along the substrate is at most 500 nm, or at most 1 pm, or at most 10 pm, or at most 100 pm, or at most 1 mm, or at most 2 mm, or at most 5 mm. The optimal size generally depends on the application. Passages should be neither too small nor too large.

[0033] It is preferred that the substrate, in particular the electrode, has no passages or openings, slots, cutouts, or recesses along the substrate or electrode that are larger than 2 mm or larger than 5 mm. This provides a universal electrode that can deliver high performance. In principle, passages should not be too large. In particular, excessively large passages can advantageously be avoided.

[0034] The method preferably comprises separating sections of the coated substrate after processing. For example, the coated sheet or substrate can be rolled to increase the degree of deformation and thus create permeability for fluid. The sheet can be stretched uniaxially or biaxially. Perforations and / or structuring can be introduced into the coated substrate, for example by means of rollers and / or knives. The coated substrate can be cut, for example, cutouts can be introduced. It is important that the coated substrate undergoes local modifications, for example, deformations, which lead to modified or deformed material sections.

[0035] It is possible for the coating to be applied only to one side of the substrate. For example, the catalyst material is applied to one side or flat side of the substrate. In this case, the other side can remain uncoated, or at least not coated with the catalyst material, to save catalyst material. Especially in combination with perforation or the introduction of passages, it is possible for the electrode to be sufficiently efficient despite only having one coated side.

[0036] The substrate preferably comprises or consists of metal. Suggested metals are aluminum, iron, titanium, and / or nickel, particularly an alloy of several metals. Steel or an alloy of metal, particularly iron, with carbon may also be used. The metal may be alloyed with carbon to form steel. Metal is an excellent basis for applying a coating and for producing an electrode. Advantageously, steel and / or aluminum may be used as inexpensive metals or elements. Nickel and / or titanium, or alloys thereof, are particularly preferred, due to their very high chemical resistance and / or strength. The substrate may comprise or consist of the same material as the coating or catalyst material.

[0037] An intermediate layer may be provided. The intermediate layer may also be referred to as an intermediate layer. If provided, the intermediate layer is preferably arranged between the coating and the substrate. More than one intermediate layer may also be provided, for example, two, three, or more intermediate layers.

[0038] The intermediate layer comprises, for example, or is a corrosion-resistant intermediate layer. The intermediate layer comprises, for example, or is a passivating intermediate layer. The intermediate layer can also comprise, or be an adhesion-promoting layer. Such an intermediate layer comprises, for example, metals, oxides, and / or nitrides, or combinations / compounds thereof. The intermediate layer can also be selected to be identical to the substrate and / or the coating in terms of material selection.

[0039] The substrate preferably has a substrate thickness of at least 0.01 mm and / or at most 1 mm. The substrate thickness is particularly preferably at least 0.05 mm and / or at most 0.80 mm in order to achieve a balanced ratio between mechanical strength for applying the coating and low costs. More preferably, the substrate thickness is at least 0.10 mm and / or at most 0.50 mm. It is also possible for the substrate thickness to be at least 0.10 mm and / or at most 0.30 mm. The substrate thickness typically refers to the thickness of the strip unwound from a roll. It is also conceivable for the substrate thickness to refer to a thickness after surface modification and before / after application. Surface modification can comprise additive, subtractive and / or changing or modifying work steps. Material can be applied / applied, ablated / removed and / or materially modified.Surface modification particularly involves processing a surface area or surface layer of the substrate. Surface modification may involve one or more steps.

[0040] The surface modification, in particular the removal of the surface layer, preferably comprises plasma etching. Plasma etching can comprise etching removal due to a chemical reaction (chemical dry etching (CDE) process) and / or physical removal due to ion bombardment. In particular, inverse magnetron sputtering and / or ion beam etching are provided. In particular, wet chemical cleaning is provided. The proposed processes can produce particularly good resistance to delamination of the coating. The aforementioned surface modification options are also particularly economical, in particular when used in a technically synergistic manner in conjunction with vapor deposition processes and / or PVD processes and / or CVD processes for applying the coating and / or an intermediate layer.

[0041] Surface modification may include roughening the substrate. Roughening may involve mechanical processing. Roughening can be performed, for example, by grinding or blasting, especially sandblasting or shot peening. Roughening particularly involves increasing the surface roughness, for example, by making the surface roughness Ra and / or Rz and / or another roughness parameter higher after roughening than before roughening. This can improve layer adhesion. Roughening can take place before or after removal.

[0042] Preferably, the step of applying an intermediate layer is provided.

[0043] An intermediate layer can be a layer that differs from the coating in terms of the material used, has an overlap with the coating, or is identical to the coating. The intermediate layer is particularly thinner than the coating and thus ensures, for example, optimal adaptation to the topography of the substrate after surface modification for the coating. This can improve the layer adhesion or adhesion of the coating to the substrate. The intermediate layer can have or be an adhesion-promoting layer, a passivating intermediate layer, and / or a corrosion-resistant intermediate layer. For example, delamination due to processing, in particular forming, waterjet cutting, etching, laser cutting, or plasma cutting, is further prevented.An adhesion-promoting layer creates good adhesion, for example, by creating a better chemical bond with the substrate, coating, and / or other intermediate layer. The adhesion-promoting layer is preferably better adapted to the lattice constants of the layers to be bonded in order to reduce interfacial tensions, compared to the absence of the adhesion-promoting layer and the layers being bonded directly.

[0044] The application of at least one further coating and / or intermediate layer may be provided to create a multilayer structure. It may be provided that multilayers or a multilayer structure is / are created. In this respect, multiple coatings and / or multiple intermediate layers may be stacked. Corresponding process steps may be supplemented or repeated to achieve this. In other words, the intermediate layer and / or the coating can be applied iteratively.

[0045] In one embodiment of the invention, after or during the surface modification, an adhesion-promoting layer can be applied as a first intermediate layer, a corrosion-resistant intermediate layer, for example, as a second intermediate layer, and the catalyst material as a coating. The application of one, two, or three layers can be repeated to achieve the multilayer structure. One or both of the intermediate layers can also be omitted or applied multiple times. The coating can also be applied more than once.

[0046] In particular, the intermediate layer comprises or consists of a catalyst material. The intermediate layer comprises, for example, nickel or, preferably, a nickel alloy.

[0047] The catalyst material can be applied using a PVD process and / or a CVD process and / or a vapor deposition process or by vapor deposition. This can provide a very robust coating made of or with the catalyst material. The intermediate layer can be applied using a vapor deposition / CVD / PVD process. In particular, the same coating process can be used for applying the intermediate layer and for applying the coating, preferably the PVD process or the CVD process. PVD or the PVD process basically refers to physical vapor deposition (PVD). This process is known in the art. CVD or the CVD process basically refers to chemical vapor deposition (CVD). This process is known in the art.

[0048] The vapor deposition process, also known as thermal evaporation or vapor deposition, preferably comprises heating the catalyst material, in particular to a temperature at the boiling point of the catalyst material, e.g., to a temperature corresponding to ± 20% of the boiling point, to generate a material vapor, and condensing the material vapor on the substrate. After condensation, the coating is present.

[0049] The PVD process can comprise sputtering or PVD sputtering. PVD sputtering is preferably performed in combination with plasma etching, inverse magnetron sputtering, and / or ion beam etching. In PVD sputtering, the cathode material can be atomized by electrical gas discharges emanating from a coating source containing the cathode material. Vaporized and / or atomized metal particles can react with a gas to create a coating containing at least the catalyst material on the substrate. An inert gas and a reactive gas are typically used in PVD sputtering.

[0050] The method is particularly preferably carried out as a continuous process. In particular, at least the application step or at least the application steps are carried out in a vacuum chamber. The vacuum chamber can be assigned to a PVD and / or CVD system. Multiple vacuum chambers can also be provided. In particular, a high vacuum is provided in the vacuum chamber. The vacuum in the vacuum chamber is typically, and prior to the application of coatings, in a range between 0.001 and 0.0001 hPa. The vacuum in the vacuum chamber during the application of coatings is typically in a range between 0.005 and 0.1 hPa. Other pressures are also conceivable, for example higher or lower than those mentioned.

[0051] In particular, a roll-to-roll and air-to-air process is provided. In particular, the unwinding, surface modification, and application, and preferably (if provided) both application steps, and preferably the processing, waterjet cutting, etching, forming, and / or laser cutting and / or plasma cutting, take place simultaneously or are carried out simultaneously, in particular on the same substrate or in one piece with the substrate. Thus, along the unwound strip, the following can be simultaneously unwound, introduced into a vacuum chamber, modified, an intermediate layer applied, a coating applied, discharged from a / the vacuum chamber, formed, and / or laser-processed and / or plasma-processed and / or separated, in particular a selection of the aforementioned activities or actions.

[0052] Preferably, the following step(s) is / are provided: introducing the substrate into a / the vacuum chamber, in particular by means of a sealing lip and / or sealing roller contacting the substrate, and / or discharging the substrate provided with the coating from a / the vacuum chamber, in particular by means of a sealing lip and / or sealing roller contacting the substrate. In particular, the introduction is provided after unwinding. The introduction is provided in particular before the surface modification and / or before the application. The discharge is preferably provided after unwinding, after the introduction, after the surface modification and / or after the application or after the application steps. The discharge and / or the introduction is / are provided in particular before a separation of the coated substrate.

[0053] A rolling step may also be provided, for example, after the coating has been applied, for example, after discharge, preferably before separation, processing, forming, waterjet cutting, etching, and / or laser cutting and / or plasma cutting. A further unrolling step may be provided, for example, before separation, processing, forming, waterjet cutting, etching, and / or laser cutting and / or plasma cutting.

[0054] The catalyst material can comprise exactly one, exactly two, or more chemical elements. The catalyst material can be selected from the group of metals, oxides, nitrides, carbides, and / or salts. The catalyst material can comprise metals, oxides, and / or nitrides.

[0055] The catalyst material may comprise or consist of a metal, an oxide, and / or a nitride. In particular, a mixture of several metals, oxides, and / or nitrides may be provided. This may be advantageous depending on the application. In particular, the catalyst materials can be selected based on raw material costs to ensure cost-effective production.

[0056] The catalyst material can be coated with exactly one, exactly two, or more than two chemical elements. Binary or ternary systems, or other systems with multiple substances as a single catalyst material, can be used.

[0057] The catalyst material can be coated or applied with a layer thickness of at least 5 nm and / or at most 2000 nm. The layer thickness is preferably at least 10 nm and / or at most 1000 nm. More preferably, the layer thickness is at least 20 nm and / or at most 500 nm. In particular, the layer thickness is at least 50 nm and / or at most 250 nm. In particular, the layer thickness is determined in a cross-section. The layer thickness is preferably determined as an average layer thickness over a section along the substrate, for example, where the section is at least 1 micrometer or at least 5 micrometers wide.

[0058] Furthermore, a system for producing electrodes is proposed. The system is particularly designed to carry out the method.

[0059] The system preferably comprises a coating system. The coating system is in particular a PVD system and / or a CVD system or a PVD and / or CVD system. The coating system is proposed to be set up for the continuous application of a catalyst material for producing a coating on a rolled sheet metal serving as a substrate in a continuous process. The system proposed to be set up a material processing system downstream of the coating system, which is set up to reshape the substrate provided with the coating and / or to process it by means of a laser and / or to process it by means of a plasma and / or a water jet and / or by means of etching or an etching process. The processing, in particular the forming, laser cutting or laser processing and / or plasma cutting or

[0060] Plasma processing and / or water jet cutting and / or etching can be carried out with particular advantage at the same time as the application.

[0061] Furthermore, an electrode is proposed. The electrode comprises, in particular, a substrate provided with a coating, and preferably an intermediate layer between the substrate and the coating. The substrate provided with the coating comprises, in particular, at least one material section that has been processed, in particular formed, laser-machined or laser-beam-machined and / or plasma-machined / plasma-beam-machined and / or water-jet-cut and / or etched, after application of a catalyst material to produce the coating. The material section is provided to create permeability of the substrate provided with the coating to a fluid, for example, liquid, electrolyte and / or gas.

[0062] The electrode can be manufactured by the method described here.

[0063] The invention further relates to the use of the electrode in a battery or accumulator and / or as an electrode in a fuel cell for generating electrical energy and / or in an electrolyzer for hydrogen production, for chlorine production, for CO production, and / or for producing other products, in particular from electrical energy.

[0064] In the context of the disclosure, the abbreviation “resp.” is a short form for “respectively” and is intended to indicate alternative, essentially equivalent and / or synonymous features or terms in order to better convey the idea or meaning of a feature or term.

[0065] “Respectively” can always be replaced with “and / or”.

[0066] The invention will be explained below by way of example with reference to the accompanying drawings using preferred embodiments, wherein the features presented below can represent an aspect of the invention both individually and in combination. They show:

[0067] Fig. 1 shows a method according to the invention in a schematic view,

[0068] Fig. 2 shows schematically various cross sections through a substrate from which an electrode is made, and

[0069] Fig. 3 shows a system according to the invention in a schematic view.

[0070] Fig. 1 shows a method for producing electrodes 1. In a step called unwinding 10, a sheet of metal, preferably nickel, is first unrolled from a roll to provide a substrate 2. Unwinding 10 occurs in this case by a tension on the roll, which comes from two counter-rotating rollers that draw in the strip. As an uncoated substrate 2, the sheet is still impermeable to a fluid.

[0071] In a step called introduction 20, after the unwinding 10, the substrate 2 is brought towards a vacuum chamber and pulled through sealing lips or sealing rollers, which contact the substrate 2 in particular on both sides or circumferentially.

[0072] During the introduction 20, the pressure is reduced so that a vacuum is present or applied to the substrate 2.

[0073] After unwinding 10 and / or insertion 20, the strip or substrate 2 looks in cross-section approximately as shown in Fig. 2A. Due to passivation, the substrate 2 has natural surface layers 3 or edge layers on both sides, in particular, which must subsequently be removed or modified.

[0074] After unwinding 10, the substrate 2 preferably has a substrate thickness 6 in the range of 0.1 mm to 0.2 mm. The surface layers 3 account for a negligible proportion of the substrate thickness 6, for example, only 1% or less.

[0075] In a step called surface modification 30, after the introduction

[0076] 20, among other things, one of the surface layers 3 of the substrate 2 is removed. This can be done by removal 35 using plasma etching, inverted magnetron sputtering, and / or ion beam etching. It may be that more than just the surface layer 3 is removed, for example, a layer of the substrate 2 lying beneath the surface layer 3.

[0077] Furthermore, roughening 38 can be provided as part of the surface modification 30, wherein the substrate 2 is roughened in particular before, after, or alternatively to the removal 35. Here, the substrate 2 can be ground or blasted. In particular, the substrate 2 is mechanically processed. The rougher or roughened surface improves the layer adhesion. In a step called application 40, an intermediate layer 4 is applied during the surface modification 30 and in particular after the removal 35 and / or roughening 38. Basically, a coating is applied here. The intermediate layer 4 essentially replaces, or purely in terms of its arrangement on the substrate 2, the surface layer 3 that was recently removed and represents a basis for a coating 5 to adhere well. In the present case, the intermediate layer 4 consists of metal, more precisely of nickel, in particular a nickel alloy.

[0078] The coating 5 is present on only one side of the substrate 2.

[0079] In this case, the intermediate layer 4 is an adhesion promoter layer. Multiple intermediate layers 4 can also be provided or applied. The intermediate layer 4 can also comprise a corrosion-resistant and / or passivating intermediate layer.

[0080] After surface modification 30 or removal 35 and after application 40, the tape or substrate 2 looks in cross-section approximately as shown in Fig. 2B. The intermediate layer 4 is now arranged on the upper side instead of the surface layer 3.

[0081] The removed surface layer 3 or applied intermediate layer 4 has / have a negligible amount with regard to the substrate thickness 6. After removal 35 and / or after application 40 of the intermediate layer 4, the substrate 2 typically continues to have the substrate thickness 6 in the range from 0.1 mm to 0.2 mm.

[0082] In a step called application 50, after the application 40 of the intermediate layer 4, a catalyst material is applied to the substrate 2, more precisely to the intermediate layer 4. In other words, a coating is applied. A coating 5 with or from the catalyst material is created or applied. The catalyst material is applied here using a PVD process. A CVD process is also conceivable. In this case, the metal platinum is the catalyst material, i.e., it is not identical to the intermediate layer 4. Other metals are conceivable. The coating 5 comprises exactly one chemical element, possibly excluding impurities in the coating 5.

[0083] Multiple coatings 5 ​​can also be provided or applied. Step 40 and / or step 50 can optionally be repeated as further steps or performed a second, third, or further time to achieve a multilayer coating structure.

[0084] After application 50 or after coating, the strip or substrate 2 looks in cross-section approximately as shown in Fig. 2C. The intermediate layer 4 and the coating 5 are arranged on the upper side. The intermediate layer 4 is an intermediate layer. In this case, the coating 5 is at least one, and preferably at least two, orders of magnitude thicker than the intermediate layer 4. In this case, the coating 5 is at least two, and preferably at least three, orders of magnitude thicker than the substrate 2.

[0085] In this case, the coating 5 has a layer thickness 7 of 150 nm (nanometers). The thickness of the intermediate layer 4 can also be included in the measurement of the layer thickness 7. The substrate 2 provided with the coating 5 has a total substrate thickness 6' in the range of 0.1 mm to 0.2 mm. A layer thickness 7 of the coating 5 of 150 nm (nanometers) or 0.15 pm (micrometers) or 0.00015 mm (millimeters) is approximately insignificant compared to the substrate thickness 6.

[0086] In Fig. 2C, the substrate thickness 6' is exaggerated or dimensionally exaggerated to visualize the coating 5. In terms of magnitude, the substrate thickness 6' corresponds to the substrate thickness 6, see, for example, Figs. 2A and 2B.

[0087] In a step called discharge 60, after the application 50 or the actual coating of the catalyst material, the substrate 2 is removed from the vacuum chamber and pulled through sealing lips or sealing rollers that contact the substrate 2 or the coating 5. During discharge 60, the pressure is increased again, and the vacuum is released to return to atmospheric pressure.

[0088] After the discharge 60, the substrate 2 provided with the coating 5 passes between two further counter-rotating rollers, which, in particular, apply strip tension to the entire preceding substrate 2 in each of the previously described states or steps. Thus, the substrate 2 is held under tension between the previously described rollers to enable a reliable CVD or PVD process. This process is a roll-to-roll and air-to-air process.

[0089] In a step called processing 70, the coated substrate 2 is reshaped after the discharge 60. This results in the coated substrate 2 becoming permeable to a fluid, in particular electrolyte and / or gas. In this step 70, the substrate 2 is stretched and, if necessary, perforated or embossed. In the present case, for example, laser cutting and / or plasma cutting and / or etching and / or waterjet cutting are optionally also performed as part of the processing 70 in order to make the substrate 2 permeable to a fluid. This is achieved, in particular, by thermal material removal and / or by separating the material.

[0090] During processing 70, at least one passage has been made in the substrate 2, wherein the substrate 2 may have been perforated with pointed tools and / or a perforating roller.

[0091] After step 70, the strip or substrate 2 looks as shown in Fig. 2D. A material section 8 was deformed and partially removed, creating a passage through the substrate 2 and the coating 5. This allows an electrolyte or a gas to flow through the essentially already formed electrode 1.

[0092] The passage has a size of less than 2 mm along the substrate 2. In a step called severing 80, after processing 70, the coated and formed substrate 2 is cut to length to provide the custom-cut electrode 1.

[0093] Steps 20, 30, 35, 38, 40, 50, 60, 70, and 80 occur simultaneously. This constitutes a continuous process or method. Thus, the aforementioned steps occur sequentially, viewed along the substrate 2 or for an individual section of the substrate 2.

[0094] Fig. 3 shows a system 100 for producing electrodes 1. The system 100 comprises a PVD and / or CVD system 110 with a vacuum chamber. The PVD and / or CVD system is configured for the continuous application 40 of a catalyst material to produce a coating 5 on a rolled sheet serving as substrate 2 in a continuous process. The system 100 or the PVD and / or CVD system 110 can perform a roll-to-roll and air-to-air process.

[0095] System 100 may perform a vapor deposition process and / or PVD sputtering. System 100 may comprise a system 110, or system 110 may comprise a vapor deposition system. System 110 may perform the PVD sputtering.

[0096] Furthermore, the system 100 comprises a material processing system 120 downstream of the PVD and / or CVD system 110. The material processing system 120 is configured to process the substrate 2 provided with the coating 5 simultaneously with the application 40, in particular to reshape it, and / or to process it by means of a laser and / or by means of plasma and / or an etching medium and / or a water jet, more precisely to make it permeable to a fluid and / or to separate it.

[0097] The material processing system 120 can also perform a separation 80 of the substrate 2 to provide electrodes 1 that are cut to size or cut to length from the endless strip. Not shown is that the coated substrate is rolled up and then unrolled after exiting the PVD and / or CVD system 110 and before entering the material processing system 120.

[0098] Shown and described is an electrode 1, comprising a substrate 2 provided with a coating 5, and an intermediate layer 4 between the substrate 2 and the coating 5, wherein the substrate 2 provided with the coating 5 has a material section 8 which, after application 40 of a catalyst material to produce the coating 5, is processed, in particular formed, water jet processed, etched processed, laser processed and / or plasma jet processed, wherein the material section 8 is provided for generating a permeability of the substrate 2 provided with the coating 5 for a fluid, cf. in particular Fig. 2D.

[0099] In particular, the substrate 2 or the electrode 1 has no passages along the substrate 2 or the electrode 1 that are larger than 2 mm.

[0100] List of reference symbols Electrode Substrate Surface layer Intermediate layer Coating , 6' Substrate thickness Layer thickness Material section 0 Unwinding 0 Infeed 0 Surface modification 5 Removing 8 Roughening 0 Applying intermediate layer 0 Applying catalyst material 0 Discharge 0 Processing 0 Separating 00 System 10 PVD and / or CVD system 20 Material processing system

Claims

Patent claims 1 . A method for producing electrodes (1 ), comprising the steps Unrolling (10) a sheet to provide a substrate (2), surface modification (30) of the substrate (2), Applying (50) a catalyst material to the substrate (2) to produce a coating (5) comprising the catalyst material, and Processing (70) of the substrate (2) provided with the coating (5), the processing (70) comprising a forming, characterized in that the forming is intended to produce a permeability of the substrate (2) provided with the coating (5) for a fluid.

2. Method according to the preceding claim, the processing (70) comprising stretching, rolling, perforating, structuring and / or punching.

3. Method according to the preceding claim, comprising a Making passages, wherein the substrate (2) is perforated with pointed tools and / or with a perforating roller, in particular during punching and / or rolling.

4. Method according to one of the preceding claims, the method comprising separating (80) sections of the substrate (2) provided with the coating (5), in particular after the processing (70).

5. Method according to one of the preceding claims, wherein the coating (5) is produced only on one side of the substrate (2).

6. Method according to one of the preceding claims, wherein the substrate (2) comprises metal, for example aluminum or iron, preferably titanium or nickel, in particular an alloy of several metals.

7. Method according to one of the preceding claims, wherein the substrate (2) has a substrate thickness (6) of at least 0.01 mm and / or at most 1 mm, preferably wherein the substrate thickness (6) is at least 0.05 mm and / or at most 0.80 mm, further preferably wherein the substrate thickness (6) is at least 0.10 mm and / or at most 0.50 mm, further preferably wherein the substrate thickness (6) is at least 0.10 mm and / or at most 0.30 mm.

8. Method according to one of the preceding claims, the surface modification (30) comprising a removal (35) of a surface layer (3) of the substrate (2), in particular plasma etching, in particular inverse magnetron sputtering and / or ion beam etching, and / or wet chemical cleaning.

9. Method according to one of the preceding claims, comprising surface modification (30) Roughening (38) of the substrate (2), preferably mechanical processing, for example grinding or blasting, in particular sandblasting or shot blasting.

10. Method according to one of the preceding claims, comprising surface modification (30) Applying (40) an intermediate layer (4), in particular wherein the intermediate layer (4) comprises an adhesion-promoting layer, a passivating intermediate layer and / or a corrosion-resistant intermediate layer, and / or Applying (40) at least one further coating (5) and / or intermediate layer (4) to produce a multilayer structure.

11. Method according to one of the preceding claims, wherein the application (40) of the catalyst material is carried out by a vapor deposition process and / or PVD and / or CVD process, and preferably wherein the application (40) of the intermediate layer (4) is carried out by a vapor deposition process and / or PVD and / or CVD process.

12. The method according to any one of the preceding claims, wherein the application (40) of the catalyst material is carried out by the PVD method, and wherein the PVD method comprises PVD sputtering.

13. Method according to one of the preceding claims, wherein the method is carried out as a continuous process with at least the step of application (40, 50) in a vacuum chamber (112), in particular roll-to-roll and air-to-air, in particular wherein the rolling, the surface modification (30) and the application (40, 50), and preferably the processing (70), take place simultaneously.

14. Method according to one of the preceding claims, comprising the steps Introducing (20) the substrate (2) into a / the vacuum chamber (112), in particular by means of a sealing lip and / or sealing roller contacting the substrate (2), and Ejecting (60) the substrate (2) provided with the coating (5) from the vacuum chamber (112), in particular by means of a sealing lip and / or sealing roller contacting the substrate (2).

15. The method according to any one of the preceding claims, wherein the catalyst material comprises exactly one, exactly two or more chemical elements, and preferably wherein the catalyst material is selected from the group of metals and / or oxides and / or nitrides and / or carbides and / or salts, and preferably wherein the catalyst material comprises metals and / or oxides and / or nitrides, and / or is coated with a layer thickness (7) of at least 5 nm and / or at most 2000 nm, preferably wherein the layer thickness (7) is at least 10 nm and / or at most 1000 nm, further preferably wherein the layer thickness (7) is at least 20 nm and / or at most 500 nm, in particular wherein the layer thickness (7) is at least 50 nm and / or at most 250 nm.

16. System (100) for producing electrodes (1), comprising a vapor deposition system and / or PVD and / or CVD system (110) which is set up for the continuous application (40) of a catalyst material for producing a coating (5) on a rolled-out sheet serving as a substrate (2) in a continuous process, and a material processing system (120) connected downstream of the vapor deposition system and / or PVD and / or CVD system (110), which is set up to process the substrate (2) provided with the coating (5), preferably simultaneously with the application (40), in order to produce a permeability of the substrate (2) provided with the coating (5) for a fluid, namely to process it, preferably by means of a laser and / or plasma and / or water jet and / or etching.

17. Electrode (1), comprising a substrate (2) provided with a coating (5), and preferably an intermediate layer (4) between the substrate (2) and the coating (5), wherein the substrate (2) provided with the coating (5) has at least one material section (8) which, after application (40) of a catalyst material to produce the coating (5), has been processed, namely formed, preferably laser beam processed and / or plasma beam processed and / or water jet cut and / or etched, wherein the material section (8) is provided for producing a permeability of the substrate (2) provided with the coating (5) for a fluid.

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