Process for producing an electrolysis cell

Abstract

Method for producing an electrolysis cell (2) for producing hydrogen, comprising the steps of producing (100) a first and a second Electrode-gas diffusion layer complex (BA, HI) by joining a first electrode (B) with a first gas diffusion layer (A) and a second electrode (H) with a second gas diffusion layer (I), coating (200) the first and second electrode-gas diffusion layer complexes (BA, HI) with first and second ionomer layers (C, G) to produce first and second electrode-gas diffusion layer ionomer complexes (BAC, HIG), and connecting (300) the first and second electrode-gas diffusion layer ionomer complexes (BAC, HIG) via a membrane (E), wherein the first electrode-gas diffusion layer ionomer complex (BAC) is arranged on a first side of the membrane (E) and the second electrode-gas diffusion layer ionomer complex (HIG) is arranged on a second side of the membrane (E).

Description

State of the art

[0001] The present invention is based on a method for producing an electrolysis cell and an electrolysis cell, preferably produced by such a method. State of the art

[0002] The use of PEM electrolyzers has become established for hydrogen production. These electrolyzers generate hydrogen in an environmentally friendly manner using electrical energy through the direct splitting of water. Electrolyzers feature a large number of interconnected electrolysis cells, each with a characteristic structure consisting of electrodes, gas diffusion layers, and a membrane.

[0003] Various methods are known for producing electrolysis cells (CCM approach, PTE approach, or DMD approach). However, each of the known methods has characteristic weaknesses. For example, the CCM approach disadvantageously leads to high contact resistance between the gas diffusion layers and the electrodes, whereas the PTE approach results in high contact resistance between the membrane and the electrodes. The DMD approach also has the disadvantage that the membrane cannot be built in a separate process, making this process approach complex and expensive. Disclosure of the invention

[0004] According to a first aspect, the invention relates to a method having the features of the independent method claim, and according to a second aspect, to an electrolysis cell according to the independent device claim. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the method according to the invention naturally also apply in connection with the electrolysis cell according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0005] The method according to the invention for producing an electrolysis cell for generating hydrogen according to the first aspect of the invention comprises the steps of producing a first and a second electrode-gas diffusion layer complex by joining a first electrode with a first gas diffusion layer and a second electrode with a second gas diffusion layer, coating the first and the second electrode-gas diffusion layer complex with a first and second ionomer layer to produce a first and second electrode-gas diffusion layer-ionomer complex and connecting the first and second electrode-gas diffusion layer-ionomer complex via a membrane, wherein the first electrode-gas diffusion layer-ionomer complex is arranged on a first side of the membrane and the second electrode-gas diffusion layer-ionomer complex is arranged on a second side of the membrane.

[0006] The method according to the invention for producing an electrolysis cell preferably serves to simplify and cost-optimize an electrolysis cell manufacturing process. According to the invention, membranes from known mass production processes can be used, thereby minimizing overall costs through economies of scale. The described construction method also makes it possible to make production adjustments quickly and easily. Furthermore, the method according to the invention makes it possible to specifically minimize contact resistances between the individual layers and thereby increase electron and proton conductivity, so that efficient, high-performance, and robust electrolysis cells can ultimately be produced in a simple and cost-effective manner using the method according to the invention.

[0007] In the context of the invention, an ionomer layer can preferably be understood as a polymer layer that can carry ions and can be applied to the electrodes of electrolysis cells in order to improve proton conduction, gas exchange and water balance.

[0008] For the most effective production of hydrogen by directly splitting water using electrical energy, it can advantageously be provided that the first electrode is an electrode having iridium oxide as its main component and / or the second electrode is an electrode having platinum on a carbon support material as its main component. The first electrode preferably represents the anode, while the second electrode represents the cathode.

[0009] To ensure the most effective gas distribution, electron conduction, and electrolyte distribution, it can advantageously be further provided that a layer containing titanium as the main component is used as the first gas diffusion layer and / or a layer containing carbon as the main component is used as the second gas diffusion layer. The first gas diffusion layer preferably represents the anode transport layer, while the second electrode represents the cathode transport layer.

[0010] With a view to a simple, rapid, cost-effective and variably adaptable production of uniform layers, it can advantageously be further provided according to the invention that the production of the first and second electrode-gas diffusion layer complex and / or the coating of the first and second electrode-gas diffusion layer complex with a first and second ionomer layer takes place in the form of a wet coating process, wherein the wet coating process is preferably carried out using a doctor blade and / or an inkjet printer and / or a screen printer and / or a slot nozzle.

[0011] To increase the efficiency and stability of the electrolysis cell produced by the present method, it can advantageously be further provided that functional layers are introduced for structural reinforcement, wherein the functional layers are preferably arranged on the ionomer layer of the first and / or second electrode-gas diffusion layer-ionomer complex. By introducing the functional layers, it is particularly possible to reduce the diffusion of hydrogen. It is understood that the functional layers can also be introduced together with the ionomer layers, for example, by applying ionomer-functional layer complexes to the first and second electrode-gas diffusion layer complexes.

[0012] With regard to reliable adhesion of the individual layers of the electrode-gas diffusion layer-ionomer complexes, it can advantageously be further provided that, before connecting the first and second electrode-gas diffusion layer-ionomer complexes via a membrane, the first and / or second electrode-gas diffusion layer-ionomer complexes are dried, wherein the drying preferably takes place by introducing an air stream and / or by irradiation with a radiation source. It is understood that a drying process can alternatively or cumulatively also be carried out before the production of the electrode-gas diffusion layer-ionomer complexes, for example, after the production of the electrode-gas diffusion layer complexes.

[0013] According to the second aspect of the invention, the invention also further provides an electrolysis cell for generating hydrogen, preferably produced by a method as described above. The electrolysis cell according to the invention comprises a layered structure consisting of a first electrode-gas diffusion layer-ionomer complex, comprising an electrode, a gas diffusion layer, and an ionomer; a second electrode-gas diffusion layer-ionomer complex, comprising an electrode, a gas diffusion layer, and an ionomer; and a membrane arranged between the first and second electrode-gas diffusion layer-ionomer complexes. Thus, the electrolysis cell according to the invention exhibits the same advantages as those already described in detail with regard to the method according to the invention.

[0014] For the most effective production of hydrogen by directly splitting water using electrical energy, it can advantageously be provided that the first electrode has iridium oxide as its main component and / or the second electrode has platinum on a carbon carrier material as its main component. The first electrode preferably represents the anode, while the second electrode represents the cathode.

[0015] To ensure the most effective gas distribution, electron conduction, and electrolyte distribution, it can advantageously be provided that the gas diffusion layer has titanium as its main component and / or the second gas diffusion layer has carbon as its main component. The first gas diffusion layer preferably represents the anode transport layer, while the second electrode represents the cathode transport layer.

[0016] To increase the efficiency and stability of the electrolysis cell, it can advantageously be further provided that functional layers are provided for structural reinforcement, wherein the functional layers are preferably arranged on the ionomer layer of the first and / or second electrode-gas diffusion layer-ionomer complex, wherein the functional layers are arranged in particular between the ionomer layer of the first and / or second electrode-gas diffusion layer-ionomer complex and the membrane. By introducing the functional layers, it is particularly possible to reduce the diffusion of hydrogen. It is understood that the functional layers can also be introduced together with the ionomer layers, for example by applying ionomer-functional layer complexes to the first and second electrode-gas diffusion layer complexes.

[0017] Advantages described in detail for the method for producing an electrolytic cell for generating hydrogen according to the first aspect of the invention apply equally to the electrolytic cell for generating hydrogen according to the second aspect of the invention.

[0018] Further advantages, features, and details of the invention will become apparent from the following description, which describes exemplary embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination.

[0019] They show schematically: Fig. 1 shows the individual steps of a method according to the invention for producing an electrolysis cell for producing hydrogen, and Fig. 2 shows an electrolysis cell according to the invention for producing hydrogen.

[0020] Fig. 1 shows a schematic representation of the individual steps of a method according to the invention for producing an electrolysis cell for producing hydrogen.

[0021] As per Fig. 1, the method according to the invention comprises the steps of producing 100 a first and a second electrode-gas diffusion layer complex BA,HI by joining a first electrode B with a first gas diffusion layer A and a second electrode H with a second gas diffusion layer I, coating 200 the first and the second electrode-gas diffusion layer complex BA,HI with a first and second ionomer layer C,G to produce a first and second electrode-gas diffusion layer ionomer complex BAC, HIG and connecting 300 the first and second electrode-gas diffusion layer ionomer complex BAC, HIG via a membrane E, wherein the first electrode-gas diffusion layer ionomer complex BAC is arranged on a first side of the membrane E and the second electrode-gas diffusion layer ionomer complex HIG is arranged on a second side of the membrane E.

[0022] In this case, the first electrode B is an electrode which has iridium oxide as its main component, whereas the second electrode H is an electrode which has platinum on a carbon carrier material as its main component.

[0023] In the present case, a layer having titanium as its main component is used as the first gas diffusion layer A, whereas a layer having carbon as its main component is used as the second gas diffusion layer I.

[0024] The production 100 of the first and second electrode-gas diffusion layer complex BA,HI and / or the coating 200 of the first and second electrode-gas diffusion layer complex BA,HI is carried out in the present case with a first and second ionomer layer C,G in the form of a wet coating process, wherein the wet coating process is carried out, for example, using a doctor blade and / or an inkjet printer and / or a screen printer and / or a slot nozzle.

[0025] In addition, the introduction of functional layers D, F for structural reinforcement can be provided in the present case, wherein the functional layers D, F can preferably be arranged on the ionomer layer C, G of the first and / or second electrode gas diffusion layer ionomer complex BAC, HIG

[0026] Fig. 2 shows a schematic representation of an electrolysis cell 2 according to the invention for producing hydrogen.

[0027] As per Fig. 2, the electrolysis cell 2 comprises a layer structure of a first electrode-gas diffusion layer-ionomer complex BAC, with an electrode B, a gas diffusion layer A and an ionomer C, a second electrode-gas diffusion layer-ionomer complex HIG, with an electrode H, a gas diffusion layer I and an ionomer G and a membrane E arranged between the first and the second electrode-gas diffusion layer-ionomer complex BAC, HIG.

[0028] The first electrode B in this case has iridium oxide as its main component, while the second electrode H has platinum on a carbon carrier material as its main component.

[0029] The first gas diffusion layer A also has titanium as its main component, while the second gas diffusion layer I has carbon as its main component.

[0030] As per Fig.2, the electrolysis cell 2 additionally has the functional layers D, F for structural reinforcement, which in the present case are arranged on the ionomer layers C, G of the first and second electrode gas diffusion layer ionomer complex BAC, HIG, in particular between the ionomer layer C, G of the first and second electrode gas diffusion layer ionomer complex BAC, HIG and the membrane E.

Claims

[1] A method for producing an electrolytic cell (2) for producing hydrogen, comprising the steps: - producing (100) a first and a second electrode-gas diffusion layer complex (BA,HI) by joining a first electrode (B) with a first gas diffusion layer (A) and a second electrode (H) with a second gas diffusion layer (I), - coating (200) the first and second electrode gas diffusion layer complexes (BA, HI) with a first and second ionomer layer (C, G) to produce a first and second electrode gas diffusion layer ionomer complex (BAC, HIG), - connecting (300) the first and second electrode gas diffusion layer ionomer complexes (BAC, HIG) via a membrane (E), wherein the first electrode gas diffusion layer ionomer complex (BAC) is arranged on a first side of the membrane (E) and the second electrode gas diffusion layer ionomer complex (HIG) is arranged on a second side of the membrane (E). [2] Method according to claim 1, characterized by that as the first electrode (B) an electrode is used which has iridium oxide as the main component and / or as the second electrode (H) an electrode is used which has platinum on a carbon carrier material as the main component. [3] Method according to claim 1 or 2, characterized by that as the first gas diffusion layer (A) a layer is used which has titanium as the main component and / or as the second gas diffusion layer (I) a layer is used which has carbon as the main component. [4] Method according to one of the preceding claims, characterized by that the production (100) of the first and second electrode-gas diffusion layer complexes (BA,HI) and / or the coating (200) of the first and second electrode-gas diffusion layer complexes (BA,HI) with a first and second ionomer layer (C,G) takes place in the form of a wet coating process, wherein the wet coating process is preferably carried out using a doctor blade and / or an inkjet printer and / or a screen printer and / or a slot nozzle. [5] Method according to one of the preceding claims, characterized by that the introduction of functional layers (D, F) is provided for structural reinforcement, wherein the functional layers (D, F) are preferably arranged on the ionomer layer (C, G) of the first and / or second electrode gas diffusion layer ionomer complex (BAC, HIG). [6] Method according to one of the preceding claims, characterized bythat before connecting (300) the first and second electrode gas diffusion layer ionomer complexes (BAC, HIG) via a membrane (E), drying of the first and / or second electrode gas diffusion layer ionomer complexes (BAC, HIG) takes place, wherein the drying is preferably carried out by introducing an air stream and / or by irradiation with a radiation source. [7] Electrolysis cell (2) for producing hydrogen, preferably produced by a method according to one of the preceding claims, comprising a layer structure of: - a first electrode-gas diffusion layer-ionomer complex (BAC), comprising an electrode (B), a gas diffusion layer (A) and an ionomer (C), - a second electrode-gas diffusion layer-ionomer complex (HIG), comprising an electrode (H), a gas diffusion layer (I) and an ionomer (G), - a membrane (E) arranged between the first and the second electrode gas diffusion layer ionomer complex (BAC, HIG). [8] Electrolysis cell (2) according to claim 7, characterized by that the first electrode (B) has iridium oxide as its main component and / or the second electrode (H) has platinum on a carbon carrier material as its main component. [9] Electrolysis cell (2) according to claim 7 or 8, characterized by that the gas diffusion layer (A) has titanium as its main component and / or the second gas diffusion layer (I) has carbon as its main component. [10] Electrolysis cell (2) according to one of claims 7 to 9, characterized bythat functional layers (D, F) are provided for structural reinforcement, wherein the functional layers (D, F) are preferably arranged on the ionomer layer (C, G) of the first and / or second electrode gas diffusion layer ionomer complex (BAC, HIG), wherein the functional layers (D, F) are arranged in particular between the ionomer layer (C, G) of the first and / or second electrode gas diffusion layer ionomer complex (BAC, HIG) and the membrane (E).

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