Method for manufacturing a lithium-ion battery and lithium-ion battery

Abstract

The invention relates to a method for producing a lithium-ion accumulator (4) which has at least one accumulator cell (6) in which an electrode (12) of a first type is arranged, wherein a passivation coating (18) comprising lithium is formed to produce the electrode (12) of the first type and wherein lithium which is precipitated during a calcination process for producing cathode material is used for this purpose.

Description

[0001] The invention relates to a method for manufacturing a lithium-ion rechargeable battery comprising at least one rechargeable cell in which an electrode of a first type is arranged. The invention also relates to a corresponding lithium-ion rechargeable battery.

[0002] Lithium-ion batteries are widely used as electrical energy storage devices. They are also used in the automotive sector, among other applications, and are primarily used as drive or traction batteries for powering hybrid or electric vehicles.

[0003] A typical lithium-ion battery consists of a positive electrode, a negative electrode, a separator, and an electrolyte. There are many different designs regarding their exact structure. However, what all designs have in common is that the lithium-ion battery contains free and therefore mobile lithium ions—in particular, lithium ions that can freely migrate back and forth through the electrolyte between the negative electrode and the positive electrode.

[0004] A possible process for the production of a lithium-ion battery is outlined in “Heimes, Heiner Hans; Kampker, Achim; Lienemann, Christoph; Locke, Marc; Offermanns (2018): Production process of a lithium-ion battery cell, VDMA Frankfurt, ISBN 978-3-947920-00-6”.

[0005] Various components are required for this and other processes. The manufacturing of some of these components is schematically illustrated, for example, in "Heimes, Heiner Hans; Kampker, Achim; Kreisköther, Kim; Michaelis, Sarah; Rahimzei, Ehsan; vom Hemdt, Ansgar (2019): Component Manufacturing of a Lithium-Ion Battery Cell, PEM of RWTH Aachen & VDMA, ISBN 978-3-947920-06-8."

[0006] The object of the present invention is to provide an advantageous method for producing a lithium-ion accumulator and an advantageously designed lithium-ion accumulator.

[0007] This object is achieved by a method having the features of patent claim 1 and by a lithium-ion accumulator having the features of patent claim 10. The advantages and preferred embodiments cited with regard to the method are also transferable to the lithium-ion accumulator, and vice versa. Advantageous embodiments with expedient further developments of the invention are specified in the dependent patent claims.

[0008] The lithium-ion rechargeable battery according to the invention has at least one rechargeable battery cell in which at least one electrode of a first type is arranged. This at least one electrode of the first type is produced by means of the method according to the invention, which is described in more detail below, in particular by means of one of the embodiment variants of the method according to the invention described in more detail below.

[0009] The at least one electrode of the first type is typically a negative electrode or a positive electrode, depending on the application. If the lithium-ion battery has multiple electrodes of the first type, each of these electrodes of the first type expediently forms a negative electrode or a positive electrode. Depending on the application, two or more electrodes of the first type are then arranged in the at least one battery cell.

[0010] Apart from that, the lithium-ion battery typically has more than one battery cell, i.e., more battery cells than the at least one battery cell. In this case, all battery cells are generally designed similarly. This means that one or more electrodes of the first type are arranged in each battery cell, or cell for short.

[0011] If the lithium-ion accumulator now has a plurality of electrodes of the first type, all of these electrodes are expediently produced by means of the method according to the invention, which is described in more detail below, in particular by means of one of the embodiment variants of the method according to the invention set out in more detail below.

[0012] Furthermore, the lithium-ion accumulator, i.e. the lithium-ion accumulator according to the invention, typically has at least one electrode of a second type, wherein the at least one electrode of the second type is usually also arranged in the aforementioned at least one accumulator cell. The at least one electrode of the second type is preferably also produced by means of the method according to the invention or at least by means of one of the embodiment variants of the method according to the invention set out in more detail below. The at least one electrode of the second type is expediently a positive electrode if the at least one electrode of the first type forms a negative electrode, and a negative electrode if the at least one electrode of the first type forms a positive electrode.

[0013] If the lithium-ion battery has multiple electrodes of the second type, each of these electrodes of the second type expediently forms a negative electrode, or each of these electrodes of the second type forms a positive electrode. Depending on the application, for example, two or more electrodes of the second type are then arranged in the at least one battery cell.

[0014] If the lithium-ion rechargeable battery also has more than one rechargeable cell, i.e., more rechargeable cells than the at least one rechargeable cell, each rechargeable cell typically has one or more electrodes of the second type. In this case, all rechargeable cells are preferably designed identically.

[0015] If the lithium-ion accumulator has a plurality of electrodes of the second type, all of these electrodes are expediently produced by means of the method according to the invention, which is described in more detail below, in particular by means of one of the embodiment variants of the method according to the invention set out in more detail below.

[0016] The method according to the invention, in turn, serves to manufacture at least one lithium-ion accumulator according to the invention of the type described above and is designed or configured accordingly for this purpose. By means of the method, i.e. the method according to the invention, at least the at least one electrode of the first type for the at least one accumulator cell of the lithium-ion accumulator, i.e. the lithium-ion accumulator according to the invention, is produced.

[0017] To produce this at least one electrode of the first type, a passivation coating comprising lithium is formed, particularly artificially, i.e., actively or deliberately. The formation of this passivation coating typically occurs in a coating process that precedes the formation of the at least one accumulator cell, and in particular, a cell assembly process during which the at least one electrode of the first type is introduced into a cell housing or into a cell casing of the at least one accumulator cell. Lithium is used for this purpose, which is a waste product during a calcination process for producing cathode material.

[0018] The method according to the invention is based, among other things, on the following considerations: Lithium-ion batteries contain so-called passivation layers or coatings. A passivation layer or coating is an intermediate layer between an electrode and an electrolyte. If the electrode is a negative electrode, this intermediate layer is also referred to as the solid electrolyte interphase (SEI). If, however, the electrode is a positive electrode, the intermediate layer is also referred to as the cathode electrolyte interphase (CEI). According to the state of the art, such intermediate layers are deliberately formed during a formation process and / or inevitably form during the initial charging and discharging processes of a lithium-ion battery. In both cases, free lithium ions, for example from the electrolyte, are permanently incorporated into the intermediate layers, so that they are subsequently no longer present as free and thus mobile lithium ions. These lithium ions are essentially lost.

[0019] Furthermore, lithium is a limited resource. Unfortunately, a certain amount of this raw material is lost during the production of components for lithium-ion batteries, especially during state-of-the-art calcination processes.

[0020] Such a calcination process is outlined, for example, in "Heimes, Heiner Hans; Kampker, Achim; Kreisköther, Kim; Michaelis, Sarah; Rahimzei, Ehsan; vom Hemdt, Ansgar (2019): Component production of a lithium-ion battery cell, PEM of RWTH Aachen & VDMA, ISBN 978-3-947920-06-8." In the calcination process described here, a process furnace is used to produce so-called Li-NMC, i.e., a nickel-manganese-cobalt material with embedded lithium. During the calcination process, lithium-containing vapor, i.e., vapor containing lithium or vapor loaded with lithium, is usually formed in the process furnace. The lithium contained therein is typically not used further and is thus lost.

[0021] The following should be noted: In a typical state-of-the-art calcination process, approximately 20% "excess" lithium is usually added to ensure that the final result is approximately 1 mole of lithium per 1 mole of nickel-manganese-cobalt material. This "excess" lithium is lost during the calcination process. However, it is not converted into gas (the calcination process usually takes place at 800°C - 1000°C, well below the boiling point of lithium). Instead, it is removed, for example, with other vapors that form, particularly water vapor and / or vapor from other solvents used to produce nickel-manganese-cobalt material (NMC precursor). Furthermore, the calcination process usually takes place either under an inert gas or in air, nitrogen, or oxygen. These gases also typically entrain molten lithium.Therefore, in the context of this application, the term lithium-containing vapor also refers to a lithium-containing exhaust gas from a calcination process, depending on the application.

[0022] A preferred variant of the method according to the invention is one in which a calcination process for producing cathode material is carried out using a process furnace, with lithium-containing vapor being generated during the calcination process. This lithium-containing vapor is then used to form the passivation coating, namely to form the passivation coating during the aforementioned coating process, which is part of the method for producing the at least one electrode of the first type. In this way, lithium that is lost during the calcination process is then used to produce cathode material.

[0023] As already explained above, the passivation coating is typically formed in a coating process that precedes the formation of the at least one accumulator cell, and in particular, a cell assembly, during which the at least one electrode of the first type is introduced into a cell enclosure or into a cell casing of the at least one accumulator cell. Further preferably, the passivation coating is also formed in a coating process that precedes the actual electrode production, i.e., in particular, before the application of an electrode material, i.e., an anode material or a cathode material, to a metal foil.

[0024] In such a case, in particular, the lithium-containing vapor is then fed into a granulate or suspension containing particles, namely electrode material particles, to form the passivation coating. For this purpose, the lithium-containing vapor is, for example, directed into a container filled with a corresponding granulate or suspension.

[0025] These electrode material particles are typically particles made of an electrode material or particles in which an electrode material is coated with a base coating.

[0026] If the at least one electrode of the first type forms a negative electrode in the finished state, the electrode material particles are, for example, particles of soft amorphous carbon with an outer layer or base coating of graphite, particles of graphite, or, for example, particles of graphite with an outer layer or base coating of hard carbon. Hard carbon is understood to mean a type of carbon that cannot be converted into graphite by heat treatment.

[0027] If, however, the at least one electrode of the first type forms a positive electrode in the finished state, the electrode material particles are, for example, particles made of a Li-NMC or, for example, particles in which such a Li-NMC is coated with a base coating of titanium oxide (TiO).

[0028] Regardless, it is expedient to form the passivation coating on the electrode material particles, thus producing coated electrode material particles, i.e., electrode material particles coated with a passivation coating. The passivation coating is then typically adjacent to an electrode material and / or to a material of a base coating or outer layer.

[0029] It is also expedient if such coated electrode material particles are subsequently applied to a metal foil to produce the at least one electrode of the first type. Depending on the application, the coated electrode material particles are initially used to produce a suspension, in particular to produce a so-called slurry.

[0030] In particular, if the at least one electrode of the first type forms a negative electrode in the finished state, a process variant is also advantageous in which the electrode material particles consist of graphite, in which the electrode material particles are further subjected to a process for forming hard carbon and in which the lithium-containing vapor for forming the passivation coating is fed to the granulate or suspension during the process for forming hard carbon.

[0031] In such a process for forming hard carbon, the electrode material particles are typically heated to a temperature above 1200°C, for example, to a temperature of approximately 1300°C. This usually occurs in an atmosphere with reduced oxygen content or in the absence of oxygen (O2).

[0032] More preferably, steam is added to the granulate or suspension in addition to the lithium-containing steam. In some cases, treatment with carbon dioxide (CO2) is carried out in a later process step.

[0033] In an alternative process, the lithium-containing vapor, preferably together with water vapor, is fed to electrode material particles, which are particles in which graphite is coated with a base coating of hard carbon. In this case, a hard carbon formation process is typically carried out before the treatment with lithium-containing vapor.

[0034] According to at least one embodiment variant, a coating or outer layer with or made of graphite is first formed on particles of soft amorphous carbon by thermal treatment. These particles with the graphite coating or outer layer are then treated with steam and the lithium-containing steam, typically after the particles have been cooled to, for example, approximately 800°C, so that lithium hydroxide (LiOH) is formed on the outermost layer of the graphite coating. Subsequently, further carbon dioxide (CO2) is added, so that the lithium hydroxide (LiOH) is converted into lithium carbonate (Li2CO3). The lithium carbonate (Li2CO3) thus formed then forms the passivation coating on the graphite of the formed coating or outer layer of graphite, which in this case represents a solid electrolyte interphase (SEI).

[0035] According to an alternative process variant, a coating or outer layer with or made of hard carbon is first produced on graphite particles, in particular natural graphite. For this purpose, hard carbon, for example, is applied to the graphite particles, and the particles are subsequently heated to approximately 1300°C, for example, to form a uniform coating. Subsequently, in particular after cooling to 800°C, for example, the lithium-containing vapor, optionally together with water vapor, is directed onto the particles, so that first a coating of lithium hydroxide (LiOH) is formed, and then, in the presence of carbon dioxide (CO2), a coating of lithium carbonate (Li2CO3).The lithium carbonate (Li2CO3) thus formed then forms the passivation coating on the hard carbon of the formed coating or outer layer of hard carbon, which in turn represents a Solid Electrolyte Interphase (SEI).

[0036] The preferred use of steam in addition to the lithium-containing steam serves to form lithium hydroxide (LiOH), which is then further preferably converted into lithium carbonate (Li2CO3) in the presence of carbon dioxide (CO2). If the lithium-containing steam already has a water content of approximately 500-1000 ppm, the additional addition of steam is not necessary and is therefore conveniently omitted.

[0037] According to another design variant, a passivation coating is produced with or from lithium oxide (Li2O). In this case, carbon dioxide (CO2) is typically not used. Preferably, only lithium-containing vapor, possibly together with water vapor, is applied to the particles.

[0038] Another useful variant of the process involves producing a passivation coating with or from lithium fluoride (LiF). In this case, hydrogen fluoride (HF) is typically applied to the particles instead of carbon dioxide (CO2). Both lithium carbonate (Li2CO3) and lithium fluoride (LiF) are typically produced from lithium hydroxide (LiOH), with lithium hydroxide (LiOH) preferably being produced by reacting the lithium-containing vapor with water from the lithium-containing vapor and / or additional water vapor.

[0039] In particular, if the at least one electrode of the first type forms a positive electrode in the finished state, a process variant is also advantageous in which the electrode material particles consist of a Li-NMC, in which the electrode material particles are subjected to a process for forming a ceramic coating and in which the lithium-containing vapor for forming the passivation coating is fed to the granulate or suspension during the process for forming the ceramic coating.

[0040] In addition to the lithium-containing vapor, oxygen (O2) and a metal, namely aluminum, titanium, or zirconium, are preferably added to the granulate or suspension. The metal is present, for example, in powder form.

[0041] Oxygen (O2) is typically only added if the lithium-containing vapor does not already contain sufficient oxygen. It is important to note that the calcination process described above is typically carried out in the presence of oxygen, so the lithium-containing vapor or exhaust gas is often already rich in oxygen and the addition of oxygen is not necessary. In these cases, the addition of oxygen is conveniently omitted.

[0042] According to at least one process variant, a passivation coating of lithium-ion-conducting lithium aluminum oxide (AlLiO2) or lithium zirconium oxide (Li2O3Zr) or lithium titanate (Li4Ti5O 12) is formed. This passivation coating then represents a Cathode Electrolyte Interphase (CEI). For this purpose, preferably aluminum oxide (Al2O3) or zirconium oxide (ZrO2) or titanium oxide (Ti2O3) is treated with the lithium-containing vapor, so that the lithium from the lithium-containing vapor together with the aluminum oxide (Al2O3) or zirconium oxide (ZrO2) or titanium oxide (Ti2O3) forms lithium-ion-conducting lithium aluminum oxide (AlLiO2) or lithium zirconium oxide (Li2O3Zr) or lithium titanate (Li4Ti5O 12 ). The resulting lithium-ion-conducting oxide is then used to form a coating on the Li-NMC particles, namely the passivation coating of lithium-ion-conducting lithium aluminum oxide (Al-LiO2) or lithium zirconium oxide (Li2O3Zr) or lithium titanate (Li4Ti5O 12). In this way, the lithium-ion conductive material is first formed and then immediately mixed with the Li-NMC electrode material particles.

[0043] According to a modified version, oxygen (O2) is added to a titanium, aluminum, or zirconium nanopowder. In this case, the corresponding metal first forms an oxide and then reacts with the lithium-containing vapor.

[0044] Alternatively or additionally, the electrode material particles from the Li-NMC are also treated with the lithium-containing vapor, forming a coating of lithium oxide (Li2O). This coating of lithium oxide then serves as a passivation coating and represents a cathode electrolyte interphase (CEI).

[0045] A previously described treatment with lithium-containing vapor is preferably carried out at a temperature of approximately 800°C. This promotes the formation of the desired passivation coating.

[0046] The method described above is used to manufacture a lithium-ion rechargeable battery, wherein the method is used to produce at least one electrode of the first type for the at least one rechargeable cell of the lithium-ion rechargeable battery. The passivation coating is formed during the process. This typically has a granular structure. The passivation coating is therefore usually composed of interconnected grains. The passivation coating generally comprises grains made of different materials.

[0047] In particular, if the at least one electrode of the first type forms a negative electrode in the finished state, the passivation coating preferably comprises grains of lithium carbonate (Li2CO3). Alternatively or additionally, the passivation coating comprises, for example, grains of lithium oxide (Li2O) and / or grains of lithium fluoride (LiF).

[0048] In particular, if the at least one electrode of the first type forms a positive electrode in the finished state, the passivation coating preferably comprises grains of lithium aluminum oxide (AlLiO2), lithium titanate (Li4Ti5O 12 ) and / or lithium zirconium oxide (Li2O3Zr). Alternatively or additionally, the passivation coating contains, for example, grains of lithium oxide (Li2O).

[0049] Further advantages, features, and details of the invention will become apparent from the claims, the following description of preferred embodiments, and the schematic drawings, in which: Fig. 1 schematically simplified a facility for the production of lithium-ion batteries, Fig. 2 a lithium-ion battery, and Fig. 3 a passivation coating.

[0050] Corresponding parts are provided with the same reference numerals in all figures.

[0051] In Fig. 1 shows a device 2 by means of which a method for manufacturing lithium-ion accumulators 4 is carried out. A corresponding lithium-ion accumulator 4 is shown in Fig. 2. It comprises, by way of example, seven accumulator cells 6, which in the exemplary embodiment are held in a support structure 8 and interconnected via an interconnection device 10.

[0052] The accumulator cells 6 of the lithium-ion accumulator 4 are all designed identically in the exemplary embodiment and each have an electrode 12 of a first type, an electrode 14 of a first type and a separator 16. In Fig. In Figure 2, the two electrodes 12, 14 and the separator 16 of one of the accumulator cells 6 are indicated by dashed frames. Each electrode 12 of the first type further forms a negative electrode in the corresponding accumulator cell 6, and each electrode 12 of the second type forms a positive electrode. Furthermore, the accumulator cells 6 are filled with a liquid electrolyte.

[0053] In the exemplary embodiment, all electrodes 12 of the first type have a passivation coating, namely a so-called SEI 18. The SEIs 18 are thereby Fig. 1, the device 2 is formed by performing a coating process. This coating process utilizes lithium, which is left over during a calcination process for producing cathode material.

[0054] The calcination process for the production of cathode material is carried out in the embodiment according to Fig. 1 is carried out using a process furnace 20 designed as a continuous furnace. During the calcination process, containers 22 containing a mixture 24 of an NMC material and lithium are passed through the process furnace 20. This creates lithium-containing vapor, which is then used to form SEI 18.

[0055] For this purpose, the lithium-containing vapor is introduced via a line 26 into a container 28 filled with granules 30. This granule 30 comprises a plurality of particles, namely electrode material particles 32. In the exemplary embodiment, the electrode material particles are graphite particles. The SEI 18 is then formed on these electrode material particles 32, thus producing coated electrode material particles 32, i.e., electrode material particles 32 coated with SEI 18.

[0056] In the exemplary embodiment, the coating process is a process for forming hard carbon, but in which the lithium-containing vapor is also added. The electrode material particles 32 are typically heated to a temperature of over 1200°C, for example, to a temperature of approximately 1300°C. This occurs in an atmosphere with a reduced oxygen content or with the exclusion of oxygen. Furthermore, water vapor is added in addition to the lithium-containing vapor. In some cases, a treatment with carbon dioxide is also carried out in a later process step.

[0057] The SEI 18 formed by the coating process typically has a granular structure. This is Fig.3. This shows a section of a cross-sectional view of an electrode material particle 32. On the right side, the SEI 18 can be seen, which borders a surface 34 of the electrode material particle 32. The SEI 18 has a large number of interconnected grains 36. Some of these grains 36, namely grains 36a, consist of lithium carbonate (Li2CO3). Depending on the application, the SEI 18 also has grains 36b of lithium oxide (Li2O), grains 36c of lithium fluoride (LiF), grains 36d of a semicarbonate, and / or grains 36e of a polyolefin.

[0058] The coated electrode material particles 18 thus produced are typically applied to a metal foil (not shown) in a subsequent process step for producing the electrodes 12 of the first type. Typically, the coated electrode material particles 18 are first used to produce a suspension, in particular to produce a so-called slurry.

[0059] Furthermore, in the exemplary embodiment, all electrodes 14 of the second type also have a passivation coating, namely a so-called CEI. Lithium, which is a precipitate during a calcination process for producing cathode material, is also used to form the CEI. Lithium-containing vapor is used here, which is discharged, for example, from the previously described process furnace 20 or from another process furnace.

[0060] This lithium-containing vapor is then fed into a container filled with granules. However, these granules contain Li-NMC particles. The CEI is formed on these particles, resulting in coated particles of an electrode material—i.e., electrode material particles coated with a passivation coating.

[0061] The coating process for forming the CEI is preferably a ceramic coating process, but with the addition of lithium-containing vapor. During this process, the Li-NMC particles are mixed with a metal powder, such as aluminum, titanium, or zirconium. Then, the lithium-containing vapor and oxygen are added.

[0062] The CEI formed by the coating process typically has a granular structure with a large number of interconnected grains. Some of these grains consist of lithium aluminum oxide (AlLiO2), lithium titanate (Li4Ti5O 12 ) or lithium zirconium oxide (Li2O3Zr), depending on which metal powder was added.

[0063] The coated electrode material particles thus produced are also typically applied to a metal foil (not shown) in a subsequent process step for producing the electrodes 14 of the second type. Typically, the coated electrode material particles are first used to produce a suspension, in particular to produce a so-called slurry. List of reference symbols 2 Facility 4 lithium-ion batteries 6 accumulator cells 8 Supporting structure 10 Wiring device 12 Electrode of a first type 14 Electrode of a second type 16 Separator 18 SEI 20 process furnace 22 containers 24 mixture 26 Line 28 containers 30 granules 32 electrode material particles 34 Surface 36 grain QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited non-patent literature

[0000] Heimes, Heiner Hans; Kampker, Achim; Lienemann, Christoph; Locke, Marc; Offermanns (2018): Production process of a lithium-ion battery cell, VDMA Frankfurt, ISBN 978-3-947920-00-6

[0004] Heimes, Heiner Hans; Kampker, Achim; Kreisköther, Kim; Michaelis, Sarah; Rahimzei, Ehsan; vom Hemdt, Ansgar (2019): Component manufacturing of a lithium-ion battery cell, PEM of RWTH Aachen & VDMA, ISBN 978-3-947920-06-8 [0005, 0020]

Claims

[1] Method for producing a lithium-ion accumulator (4) which has at least one accumulator cell (6) in which an electrode (12) of a first type is arranged, wherein a passivation coating (18) comprising lithium is formed to produce the electrode (12) of the first type and wherein lithium which falls away in a calcination process for producing cathode material is used for this purpose. [2] The method according to claim 1, wherein the calcination process is carried out by means of a process furnace (20) in which lithium-containing vapor is generated during the calcination process, and wherein the lithium-containing vapor is used to form the passivation coating (18). [3] Method according to claim 1 or 2, wherein the lithium-containing vapor for forming the passivation coating (18) is fed to a granulate (30) which comprises particles (32) of an electrode material, namely electrode material particles (32). [4] The method of claim 3, wherein the passivation coating (18) is formed on the electrode material particles (32) to produce coated electrode material particles (32). [5] Method according to claim 4, wherein coated electrode material particles (32) are applied to a metal foil to produce the electrode (12) of the first type. [6] Method according to claim 4 or 5, wherein the granulate (30) comprises electrode material particles (32) made of graphite, wherein the electrode material particles (32) are subjected to a process for forming hard carbon and wherein the lithium-containing vapor for forming the passivation coating (18) is supplied to the granulate (30) during the process for forming the hard carbon. [7] Method according to claim 6, wherein water vapor is supplied to the granulate (30) in addition to the lithium-containing vapor. [8] The method according to claim 4 or 5, wherein the granulate comprises electrode material particles made of a Li-NMC, wherein the electrode material particles are subjected to a process for forming a ceramic coating, and wherein the lithium-containing vapor for forming the passivation coating is supplied to the granulate during the process for forming the ceramic coating [9] Process according to one of claims 3 to 8, wherein oxygen is supplied to the granulate in addition to the lithium-containing vapor and a metal, namely aluminum, titanium or zirconium. [10] Lithium-ion accumulator (4) comprising an accumulator cell (6) in which an electrode (12) of a first type is arranged, which electrode is produced by means of a method according to one of the preceding claims.

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