Method for producing an electrochemical cell, electrochemical cell, electrolysis cell device, and fuel cell device

Abstract

The invention relates to a method (10) for producing an electrochemical cell (12), in particular an electrolysis cell (14), comprising a cell substrate (16), a first electrode layer (26), a second electrode layer (32), and an electrolyte layer (28) situated between the first electrode layer (26) and the second electrode layer (32), wherein the electrolyte layer (28) is deposited using a physical vapor deposition (PVD) method. According to the invention, a sealing layer (30) is deposited on the electrolyte layer (28) by means of atomic layer deposition (ALD).

Description

[0001] R. 413379

[0002] - 1 -

[0003] Description

[0004] title

[0005] Method for manufacturing an electrochemical cell, electrochemical cell, electrolysis cell device and fuel cell device

[0006] The invention relates to a method for manufacturing an electrochemical cell, in particular an electrolysis cell with a PVD electrolyte layer and an ALD sealing layer according to the preamble of the independent claim. The invention further relates to an electrochemical cell, an electrolysis cell device, and a fuel cell device.

[0007] State of the art

[0008] A key problem with solid oxide electrolysis cells (SOECs) operating at low temperatures of around 650°C is the gas permeability of the electrolyte layer. Thin electrolyte layers are required for efficient operation to minimize ohmic resistance. However, thin layers, such as those produced by physical vapor deposition (PVD), are prone to defects like micropores and layer delamination. These defects lead to undesirable permeability to the reaction gases hydrogen and oxygen, or water vapor. This gas leakage reduces the cell's Coulombic efficiency because some of the supplied energy is lost to the unwanted reaction of the permeated gases. Furthermore, the leakage can lead to electrode degradation and a shortened cell lifespan.

[0009] Alternatively, denser layers can be produced using atomic layer deposition (ALD). ALD enables the deposition of very thin yet dense layers that minimize gas leakage. However, the disadvantage of ALD processes lies in the very low deposition rates, which leads to long process times and high manufacturing costs. Therefore, there is a need for an electrolyte layer that ensures both low gas permeability and cost-effective manufacturability. R. 413379

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[0011] Disclosure of the invention

[0012] Advantages

[0013] The present invention describes a method for producing an electrochemical cell, in particular an electrolysis cell, comprising a cell substrate, a first electrode layer, a second electrode layer, and an electrolyte layer arranged between the first and second electrode layers. According to the invention, the electrolyte layer is deposited by means of a physical vapor deposition (PVD) process, and a sealing layer is deposited onto the electrolyte layer by means of atomic layer deposition (ALD).

[0014] By combining PVD and ALD for the electrolyte layer and the sealing layer, the advantages of both processes are utilized. The PVD layer enables rapid and cost-effective deposition of the electrolyte layer, while the ALD layer effectively seals the pores and defects of the PVD layer. This results in significantly reduced gas leakage and improves the performance and lifespan of the electrochemical cell.

[0015] An electrochemical cell is understood to be, in particular, an arrangement that provides usable electrical energy through chemical reactions or is intended for the chemical production or conversion of substances by applying a voltage. An electrochemical cell has at least two or more functional layers. The functional layers comprise at least two electrode layers and a separating layer or electrolyte layer. The electrode layers each function as an electron conductor and are conductively connected to the separating layer or electrolyte layer. Also important for the electrode layers are ion transport and catalytic activity.

[0016] Oxygen exchange capacity between the electrode layer and the gas phase. The separating layer or electrolyte layer primarily functions as an ion conductor, especially for oxygen ions. Furthermore, the separating layer...

[0017] Electrolyte layer provided for the separation of the two gas compartments, for example the separation between air and fuel gas in a fuel cell. R. 413379

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[0019] In particular, the term "electrochemical cell" shall be understood to mean a fuel cell or an electrolysis cell. In this context, the terms "fuel cell" and "electrolysis cell" shall be understood to mean, in particular, at least a part, especially a subassembly, of a fuel cell system, in particular a solid oxide fuel cell system, and / or an electrolysis cell device, in particular a high-temperature electrolyzer. In particular, the electrochemical cell may also comprise the entire fuel cell, in particular the entire solid oxide fuel cell, the entire electrolyzer, in particular the entire high-temperature electrolyzer, a stack of several stacked fuel cells and / or electrolysis cells, and / or a combination of several stacks of fuel cells and / or electrolysis cells.

[0020] Preferably, the electrochemical cell is designed to convert a fuel into electrical energy in an electrochemical combustion process by supplying an oxidant. Alternatively or additionally, the electrochemical cell is designed to separate a fluid into at least two components in a separation process by supplying electrical energy. "Designed" is understood to mean, in particular, specially configured, specially designed, and / or specially equipped. The phrase "designed" means, in particular, that an object fulfills and / or performs this specific function in at least one application and / or operating state.

[0021] Preferably, the electrochemical cell comprises at least one functional layer, and in particular at least three functional layers. A functional layer is preferably understood to be a layer that is directly involved in the electrochemical reaction process and / or the separation process carried out by means of the electrochemical cell. In particular, two functional layers are configured as electrode layers, especially for use as the cathode and / or anode. Preferably, at least one electrode layer is configured as an oxidant electrode or air electrode, especially for contact with the oxidant and / or a decomposition product. Preferably, R. 413379

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[0023] at least one electrode layer is designed as a fuel electrode, in particular for contact with the fuel and / or another fission product.

[0024] Preferably, at least one functional layer is designed as an electrolyte layer. Preferably, at least one separating layer is arranged on at least one electrode layer, in particular between two electrode layers.

[0025] A cell substrate can, in particular, comprise a sintered or unsintered ceramic or metal-ceramic substrate. It is also possible for the cell substrate to comprise a sintered or unsintered powdered metallic substrate. It is also conceivable that the cell substrate comprises at least a portion of a metal; for example, the cell substrate can comprise a sheet with drilled, etched, and / or punched holes, and / or expanded metal, foam, mesh / fabric, or the like. In particular, the cell substrate can be highly porous or have large pores and / or openings; for example, the cell substrate can have meshes, drilled or etched holes, or the like. Advantageously, the cell substrate is made entirely of metal.

[0026] Advantageously, the first electrode layer is a fuel gas electrode layer. Preferably, the first electrode layer comprises a mixture of Ni or NiO with doped cerium oxide, e.g., Gd-doped cerium oxide (CGO) or Sm-doped cerium oxide (SDC). It is also conceivable that the first electrode layer comprises a mixture of Ni or NiO with stabilized zirconium oxide, in particular zirconium oxide stabilized with Sc, Y, and / or Ce, for example, scandium-stabilized zirconium oxide (ScSZ), yttrium-stabilized zirconium oxide (YSZ), scandium / yttrium-stabilized zirconium oxide (ScYSZ), scandium / cerium-stabilized zirconium oxide (ScCeSZ), or the like. It is also possible that the first electrode layer has oxides with a perovskite structure, for example La(Sr)Ga(Mg)O3-o, SrCe(Yb)O3-o or La-Ca-Cr-Oxide, optionally mixed with doped cerium oxide or stabilized zirconium oxide.

[0027] In particular, the first electrode layer can be a suspension-based layer. This allows advantageous layer thicknesses to be achieved particularly easily and reliably. Typically, a layer thickness significantly greater than 2 pm is required for optimal function of the first functional layer in the cell. Advantageous R. 413379

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[0029] The first functional layer can be deposited using screen printing. However, other processes such as gravure printing, flexographic printing, pad printing, spraying, film casting, or slot-die coating are also conceivable for applying the first functional layer.

[0030] Advantageously, the electrolyte layer has a thickness between 0.1 pm and 10.0 pm, preferably between 0.5 pm and 5.0 pm, and particularly preferably between 1.0 pm and 3.0 pm. In this way, electrochemical cells with low ionic resistance, good electrical insulation, and good gas tightness can be produced. Stabilized zirconium oxide is a suitable electrolyte material, in particular zirconium oxide stabilized with Sc, Y, and / or Ce, for example, scandium-stabilized zirconium oxide (ScSZ), yttrium-stabilized zirconium oxide (YSZ), scandium / yttrium-stabilized zirconium oxide (ScYSZ), scandium / cerium-stabilized zirconium oxide (ScCeSZ), or the like. By using stabilized zirconium oxide as the electrolyte material, the risk of cell damage during operation due to changes in the electrolyte volume when the oxygen partial pressure in the combustion gas chamber changes, as occurs when using doped cerium oxide as the electrolyte material, is eliminated.

[0031] It is also conceivable that the electrolyte layer comprises doped cerium oxide, e.g., Gd-doped cerium oxide (CGO), Sm-doped cerium oxide (SDC), or Pr-doped cerium oxide (PDC). In particular, it is conceivable that the electrolyte layer could also be formed as a multilayer consisting of stabilized zirconium oxide and a doped cerium oxide layer. For example, it is possible that the electrolyte layer comprises several alternating layers of stabilized zirconium oxide and doped cerium oxide.

[0032] Examples of physical vapor deposition (PVD) include magnetron sputtering or reactive magnetron sputtering, high power impulse magnetron sputtering (HiPIMS), gas flow sputtering, or (plasma-assisted) electron beam evaporation.

[0033] The second electrode layer, the air electrode, is advantageous. Advantageously, the second electrode layer is deposited using a suspension-based process, R. 413379

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[0035] especially with a printing process, for example screen printing. The second electrode layer can, for example, consist of oxides with a perovskite structure, such as La-Sr-Co oxide (LSC), La-Sr-Co-Fe oxide (LSCF), La-Sr-Mn oxide (LSM). The second electrode layer can also, for example, consist of oxides with a perovskite structure combined or mixed with doped cerium oxide – for example, CGO, SDC – and / or combined or mixed with stabilized zirconium oxide, such as YSZ, ScSZ, ScYSZ, ScCeSZ, and the like.

[0036] Atomic Layer Deposition (ALD) is a method of chemical vapor deposition (CVD) and makes it possible to create very thin, dense layers via multi-stage chemical layer deposition.

[0037] The deposition of the sealing layer using ALD can take place immediately after the coating of the electrolyte layer by PVD in the same system, particularly without interrupting the vacuum. Alternatively, the sealing layer can be deposited later onto the electrolyte layer in a separate system.

[0038] Advantageously, the sealing layer is arranged between the electrolyte layer and the air electrode.

[0039] Advantageous further developments of the method are possible due to the features listed in the dependent claims.

[0040] The process is further improved by making the PVD process a reactive sputtering process with oxygen as the reactive gas, specifically a reactive magnetron sputtering process with oxygen as the reactive gas. This allows the desired oxides to be formed on the electrolyte layer when the target contains metallic components, such as metallic Zr and / or Sc. Even when metals in the target are present as compounds with other elements, such as nitrogen, the desired oxide compounds can be produced in this way. R. 413379

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[0042] By using a reactive sputtering process with oxygen as the reactive gas, the electrolyte layer can be produced with a defined stoichiometry and high quality, which further improves the performance of the electrochemical cell.

[0043] The present invention further describes an electrochemical cell, in particular an electrolysis cell, comprising a cell substrate, a first electrode layer, a second electrode layer, and an electrolyte layer arranged between the first and second electrode layers, wherein a sealing layer is arranged on the electrolyte layer. According to the invention, the electrochemical cell is manufactured using a method according to the present invention. The electrochemical cell according to the invention benefits from the advantages of the manufacturing method according to the invention. The combination of PVD and ALD for the electrolyte layer and sealing layer reduces gas leakage and increases the efficiency and lifespan of the cell.

[0044] The electrochemical cell is further improved by ensuring that the sealing layer has a thickness between 1 nm and 200 nm, preferably between 5 nm and 100 nm, and particularly preferably between 10 nm and 50 nm. Optimizing the thickness of the sealing layer achieves an optimal compromise between gas tightness and the layer's resistance.

[0045] It is also advantageous if the sealing layer contains zirconium dioxide. The use of zirconium dioxide as a sealing material offers high chemical stability and compatibility with the other cell components.

[0046] It is also advantageous if the zirconium dioxide is stabilized with yttrium and / or scandium. Stabilizing the zirconium dioxide with yttrium and / or scandium improves the conductivity and stability of the sealing layer.

[0047] It is also advantageous if the sealing layer contains gadolinium-doped cerium oxide. Gadolinium-doped cerium oxide is an excellent sealing material due to its high conductivity and chemical stability. In particular, in combination with an electrolyte layer of YSZ and / or ScSZ, a CGOR. 413379

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[0049] The sealing layer prevents strontium diffusion from the air electrode into the electrolyte layer.

[0050] It remains advantageous if the sealing layer contains aluminum oxide. Aluminum oxide offers excellent gas tightness and chemical stability as a sealing material. Aluminum oxide (Al₂O₃) has proven particularly suitable for sealing the pores of the electrolyte layer, especially a ScYSZ electrolyte layer.

[0051] The present invention further describes an electrolysis cell device for producing fuel from at least one base material and electric current, in particular hydrogen from electric current and water, comprising at least one electrolysis cell stack, a base material supply, in particular a water supply, further comprising an anode exhaust gas guide and cathode exhaust gas guide as well as control electronics and power electronics, wherein the electrolysis cell stack comprises at least one electrolysis cell which is designed as an electrochemical cell according to the present invention.

[0052] The use of the electrochemical cell according to the invention in the electrolysis cell device enables efficient and reliable hydrogen production. The reduced gas leakage of the cells leads to higher efficiency and lower operating costs.

[0053] The present invention further describes a fuel cell device for generating electric current from a fuel, in particular hydrogen and / or natural gas, and air, comprising at least one fuel cell stack, a fuel supply, an air supply, an anode exhaust gas guide and cathode exhaust gas guide, as well as control electronics and power electronics.

[0054] According to the invention, the fuel cell device comprises a fuel cell stack, which includes at least one fuel cell designed as an electrochemical cell according to the present invention. The use of the electrochemical cell according to the invention in the fuel cell device leads to higher efficiency and performance of the fuel cell. R. 413379

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[0056] Furthermore, the electrochemical cell according to the invention can be used in electrochemical compressors as well as in gas separation processes.

[0057] Drawings

[0058] The drawings illustrate exemplary embodiments of the method for manufacturing an electrochemical cell, the electrochemical cell itself, an electrolysis cell device, and a fuel cell device, and explain them in more detail in the following description. They show

[0059] Figure 1 shows the electrochemical cell according to the present invention, produced by the method according to the present invention.

[0060] Figure 2 shows a schematic representation of the process for manufacturing the electrochemical cell,

[0061] Figure 3 shows a schematic representation of an electrolysis cell device with an electrochemical cell according to the present invention as well as

[0062] Figure 4 shows a schematic representation of a fuel cell device with an electrochemical cell according to the present invention.

[0063] Description

[0064] In the different versions, identical parts receive the same reference numbers.

[0065] Figure 1 shows an electrochemical cell 12, which is exemplary configured as an electrolysis cell 14; Figure 2 shows a schematic overview of the sequence of process steps S1 to S6 of a process 10 for the production of this electrochemical cell 12.R. 413379

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[0067] In a first step, S1 provides a cell substrate 16 and coats a transfer substrate. For example, the cell substrate 16 is a metallic cell substrate, made as a sheet with a plurality of through openings 20. The openings 20 can be etched, punched, drilled or formed using an expanded metal process.

[0068] The process uses, as an example, a transfer lamination process in which layers are first applied to a transfer substrate, then these layers are laminated onto the cell substrate with the transfer substrate, and in a subsequent step the transfer substrate is removed - the transfer substrate is therefore not part of the finished electrochemical cell.

[0069] This has the advantage that very thin and smooth layers can be applied using the transfer substrate, since the transfer substrate – unlike the cell substrate, if applicable – can be very flat and smooth. This is possible because the transfer substrate is only used for the manufacturing process and is not part of the electrochemical cell. After the transfer substrate is removed, the surface of the first layer – the former contact area of ​​the transition layer to the transfer substrate – exhibits high flatness and low roughness, which is advantageous for the subsequent application of a thin, dense functional layer, particularly the separating layer or electrolyte layer, in a later process step. In this way, the risk of defects forming in the functional layer, especially the separating layer or electrolyte layer, due to pores or defects at "high spots" in the transition layer, can be reduced.

[0070] However, transfer lamination is not essential for the present invention; it is also possible that the layers are deposited or applied directly onto the cell substrate 16, in particular the functional layers, especially electrode layers.

[0071] In the exemplary embodiment, in step S1a the metallic cell substrate 16 is coated with a metal oxide as a barrier layer 22. The barrier layer 22 acts as a chemical barrier to the first electrode layer 26R applied in step S1b. 413379

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[0073] The metal oxide of barrier layer 22 is formed from CGO as an example. In variants, barrier layer 22 contains a spinel.

[0074] In the exemplary embodiment, the barrier layer 22 is coated using a thin-film process, for example with the PVD method "magnetron sputtering". In alternative methods, the coating can be applied, for example, using suspension-based processes such as screen printing or suspension spraying.

[0075] In step S1B, a thin suspension-based transition layer 24 is applied to the transfer substrate. For example, the transfer substrate is designed as a polymer film. In this embodiment, the transition layer is applied with a wet film thickness of 4.0 pm. In the dried and sintered state, the dry film thickness of the transition layer is then 2.0 pm.

[0076] As an example, the transition layer 24 is applied using gravure printing; other processes such as screen printing, flexographic printing, or spray coating are conceivable in variations. The transition layer 24 is then dried. In this example, the transition layer 24 consists of NiO-CGO in a suspension. The particle sizes, mixing ratios, and additives are selected such that, after subsequent sintering at below 1100 °C (step S4), a microstructure with as few pores as possible and / or a fine pore structure is achieved. In this embodiment, a particle size distribution is used for the powders of the transition layer 24 in which 50% of the particles have a particle size of less than 0.1 pm, 97% of the particles have a particle size of less than 1.0 pm, and no particles are larger than 10.0 pm.

[0077] After drying, a suspension-based first electrode layer 26 is applied to the transition layer 24. For example, the first electrode layer 26 is a fuel gas electrode layer. In this embodiment, the wet film thickness of the first electrode layer 26 is 40 pm. In the dried and sintered state, the dry film thickness of the first electrode layer 26 is approximately 20 pm. In variants, the wet film thickness of the first electrode layer 26 is preferably between 1.0 pm and 100.0 pm, particularly preferably between 10 pm and 50 pm, which corresponds to a preferred dry film thickness in the dried and sintered state. R. 413379

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[0079] between 0.5 pm and 50 pm, particularly preferably between 5 pm and 25 pm. As an example, the first electrode layer 26 is applied by screen printing.

[0080] The first electrode layer 26 is then completely dried, or alternatively, at least partially dried. In the exemplary embodiment, the first electrode layer 26, or its suspension, comprises NiO-CGO. The particle sizes, mixing ratios, and additives are selected such that, after subsequent sintering at below 1100°C (see S4), the first electrode layer 26 achieves the most efficient and sufficiently age-resistant microstructure possible.

[0081] In a subsequent step S2, the transition layer 24 and the first electrode layer 26 are laminated from the transfer substrate 18 onto the coated metallic cell substrate 16. In the exemplary embodiment, lamination is carried out by pressing at 80°C and with a pressure of 30 MPa. In variants, lamination is carried out by pressing at temperatures between 50°C and 100°C, and at pressures between 5 MPa and 50 MPa. After lamination, the first electrode layer 26 is arranged between the transition layer 24 and the cell substrate 16. By way of example, the barrier layer 22 is arranged between the cell substrate 16 and the first electrode layer 26.

[0082] In a subsequent step S3, the transfer substrate is removed by peeling. The layered assembly consisting of cell substrate 16, first electrode layer 26, and transition layer 24 is then sintered in a step S4. This sintering process is carried out, for example, at 1050 °C in air for a period of 2 hours.

[0083] Subsequently, in step S5, an electrolyte layer 28 is deposited onto the sintered transition layer 24 by a sputtering process. In the exemplary embodiment, the second electrolyte layer 28 has a thickness of 2 pm. In variants, the thickness of the second electrolyte layer 28 is between 1 pm and 3 pm. By way of example, the second electrolyte layer 28 is applied by means of reactive magnetron sputtering. For this purpose, a target with a metallic alloy of 80 at.% Zr, 18 at.% Sc, and 2 at.% Y is used. Sc and Y are additive metals intended to deposit the R in the electrolyte layer 28. 413379

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[0085] The aim is to stabilize or dope zirconium oxide. The amount of additional metals in the target is therefore 20 at% relative to the metals in the target.

[0086] As an example, argon is used as the process gas with an oxygen content varying between 2 mol% and 4 mol%. The oxygen content is controlled according to the cathode voltage. For example, the cathode voltage is maintained in a range between 415 V and 435 V by gradually increasing the oxygen content between 2.5 mol% and 3.7 mol% during the sputtering process.

[0087] For example, the coating process takes about 25 minutes.

[0088] The process gas is, for example, at a pressure of 8 pbar, and sputtering is carried out with a power of 500 W. In this embodiment, the electrolyte layer 28 has ScYSZ as the electrolyte material; alternatives include, for example, ScSZ, ScYAlSz, or ScCeSZ.

[0089] Subsequently, a sealing layer 30 is deposited onto the electrolyte layer 28. For example, the thickness of the sealing layer is 3080 nm. The sealing layer 30 is applied directly to the electrolyte layer 28 by atomic layer deposition (ALD). For example, the sealing layer 30 is made of aluminum oxide (Al₂O₃).

[0090] In a subsequent step S6, the second electrode layer 32 is applied to the sealing layer 30. In the exemplary embodiment, the second electrode layer 32 has an air electrode. Advantageously, a current collector layer or contact layer 34 is applied to the second electrode layer 32. For example, both the second electrode layer 32 and the contact layer 34 are applied using a suspension-based process, e.g., screen printing. The second electrode layer 32 has, for example, LSC-CGO. The contact layer 34 has, for example, LSC. Optionally, a further sintering step can follow, in which the sintering takes place at a temperature below the temperature that was used for the sintering S4 of the first electrode layer 26 and the transition layer 24. R. 413379

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[0092] Figure 3 shows an electrolysis cell device 36 for producing hydrogen from electricity and water. The electrolysis cell device 36 has an electrolysis cell stack 38, which in turn comprises a plurality of stacked electrolysis cells 14. The electrolysis cells 14 are shown as high-temperature SOECs. The electrolysis cell stack 38 is supplied with water via a water inlet 40 and with electricity via a power electronics unit 42.

[0093] Figure 4 shows a fuel cell device 44 for generating electricity from hydrogen and air. The fuel cell device 44 comprises a fuel cell stack 46, which includes a plurality of stacked electrochemical cells 12, configured as fuel cells 48. The fuel cells 48 are shown as high-temperature SOFCs. The fuel cell stack 46 is supplied with hydrogen via a fuel feed 50 and with air via an air feed 52. The hydrogen and air are metered by means of control electronics 54, which actuate corresponding valves and fans. The voltage drawn from the fuel cell stack 46 is converted as required by power electronics 42.

Claims

R. 413379 - 15 - Claims 1. Method (10) for producing an electrochemical cell (12), in particular an electrolysis cell (14), comprising a cell substrate (16), a first electrode layer (26), a second electrode layer (32), an electrolyte layer (28) arranged between the first electrode layer (26) and the second electrode layer (32), wherein the electrolyte layer (28) is deposited by means of a physical vapor deposition (PVD) process, characterized in that a sealing layer (30) is deposited onto the electrolyte layer (28) by means of atomic layer deposition (ALD).

2. Method (10) according to claim 1, characterized in that the PVD method is a reactive sputtering method using oxygen as the reactive gas.

3. Electrochemical cell (12), in particular electrolysis cell (14), comprising a cell substrate (16), a first electrode layer (26), a second electrode layer (32), an electrolyte layer (28) arranged between the first electrode layer (26) and the second electrode layer (32), wherein a sealing layer (30) is arranged on the electrolyte layer (28), manufactured by a method according to claim 1 or 2.

4. Electrochemical cell (12) according to claim 3, characterized in that the sealing layer (30) has a layer thickness between 1 nm and 200 nm, preferably between 5 nm and 100 nm, particularly preferably between 10 nm and 50 nm.

5. Electrochemical cell (12) according to one of claims 3 to 4, characterized in that the sealing layer (30) comprises zirconium dioxide (ZrCh).

6. Electrochemical cell (12) according to claim 5, characterized in that the zirconia is stabilized with yttrium (Y) and / or scandium (Sc). R. 413379 - 16 - 7. Electrochemical cell (12) according to one of claims 3 to 6, characterized in that the sealing layer (30) comprises gadolinium-doped cerium oxide (CGO).

8. Electrochemical cell (12) according to one of claims 3 to 7, characterized in that the sealing layer (30) comprises aluminium oxide (Al2O3).

9. Electrolysis cell device (36) for producing fuel from at least one base material and electric current, in particular hydrogen from electric current and water, comprising at least one electrolysis cell stack (38), a base material supply, in particular a water supply (40), further comprising an anode exhaust gas guide and cathode exhaust gas guide as well as control electronics (54) and power electronics (42), wherein the electrolysis cell stack (38) comprises at least one electrolysis cell (14) which is designed as an electrochemical cell (12) according to one of claims 3 to 8.

10. Fuel cell device (44) for generating electric current from a fuel, in particular hydrogen and / or natural gas, and air, comprising at least one fuel cell stack (46), a fuel supply (50), an air supply (52), an anode exhaust guide and cathode exhaust guide as well as control electronics (54) and power electronics (42), wherein the fuel cell stack (46) comprises at least one fuel cell (48) which is designed as an electrochemical cell (12) according to one of claims 3 to 8.

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