Method for manufacturing a conductive conductor strand having at least one carbon conductor

Abstract

A method for producing an electrically conductive conductor strand (1) comprising at least one carbon conductor (3), comprising: a) producing or providing a conductor strand (1) as an intermediate product comprising at least one carbon conductor (3), in particular comprising graphite, pyrolytic graphite, graphene, graphene and / or carbon nanotubes; b) introducing the conductor strands (1) and one or more intercalants (2), in particular one or more metal halides or one or more organic alkali metals, into the gas or liquid phase of the reactor volume (5), the intercalants being suitable for intercalating the conductor strands (1) into the material of the at least one carbon conductor (3); c) carrying out a heat treatment of the conductor strands (1), in which the reactor volume (5) is brought to a process temperature for initiating intercalation (4), so that atoms or molecules of the intercalant (2) are embedded in the material of the respective carbon conductors (3), in particular in the interlayer regions of the multi-layer carbon structure, and are deposited in the carbon structure of the carbon conductors (3); A method having the following.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a conductive conductor strand having at least one carbon conductor.

Background Art

[0002] Carbon conductors are known from the prior art. For example, from the prior art, electrical conductors including graphite, pyrolytic graphite, carbon nanotubes or graphene are known. In order to increase their conductivity, it is known to dope carbon conductors. For example, from German Patent Application Publication No. 102019220177, it is known that graphene can be doped with intrinsically doped graphene. International Publication No. 2021 / 004692 shows a method by which graphene can be doped with an oxide on a transition metal so as to increase conductivity. European Patent No. 0081004 shows that the conductivity of graphite can be increased by doping with BF3, SiF4, HfF4, TiF4, ZrF4, PF5, NbF5, TaF5, AsF5 or SbF5 respectively.

[0003] From Chinese Patent Application Publication No. 106744888, it is known that graphene in a graphene dispersion can be produced by adding aluminum fluoride and an amine. Also, from Nakajima, T., Kawaguchi, M., & Watanabe, N. (1981) Ternary intercalation compound of graphite with aluminum fluoride and fluorine, Nature Research Journal, Vol. 36(11), 1419 - 1423, it is also known that when equimolar fluorine is present in the gas phase and a sufficiently high temperature exists, aluminum fluoride intercalates into graphite. The drawback is that intercalation requires high temperatures, and this is because fluorine fluorinates graphite already at 300 °C and thus deteriorates the conductivity.

[0004] EP 0212940 A1 shows that when the sublimation point or boiling point of a metal chloride is low, it is particularly suitable for intercalation doping. Therefore, EP 0212940 A1 uses aluminum chloride with a very low sublimation point to intercalate other metal chlorides with a high sublimation point or boiling point into graphite more rapidly and at a lower temperature.

[0005] Similarly, it is a disadvantage in the prior art that, as shown by Matsumoto, et al. (Matsumoto, K., Minori, D., Takagi, K., & Hagiwara, R. (2014), Expansion of tetrachloroaluminate - graphite intercalation compound by reaction with anhydrous hydrogen fluoride, Carbon, 67, 434 - 439), when graphite intercalated with a metal chloride is fluorinated with anhydrous hydrofluoric acid (HF), gas is generated in the graphite, causing the graphite to expand. This also causes expansion in conductors and ultimately leads to the destruction of the conductors.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Non-Patent Literature

[0007]

Non-Patent Literature 1

Non-Patent Literature 2

Summary of the Invention

Means for Solving the Problems

[0008] In contrast, the method according to the present invention having the features of the independent claims has the advantage that a conductor strand provided with a carbon conductor having higher conductivity than the prior art and having temperature resistance up to at least 200 °C can be manufactured.

[0009] The features of the method of the independent claims, according to the first embodiment, produce a final product, and according to the second and third embodiments, produce an intermediate product that can be processed into the final product by further steps according to the present invention.

[0010] Advantageous improvements and modifications of the method described in the independent claims are possible by the methods described in the dependent claims. According to the first embodiment, the intercalant is at least one metal fluoride, particularly aluminum fluoride (AlF3), zirconium fluoride (ZrF4), iron fluoride (FeF3), magnesium fluoride (MgF2), and the metal of the metal fluoride is selected from one of Groups 2, 4, 5, 6, 8, 10, 11, 12, or 13 of the periodic table. The method according to the first embodiment using a metal fluoride as the intercalant has the advantage that the required process steps are few and thus very easy because intercalation of the intercalant or dopant that directly brings about an increase in conductivity is performed as a strong Lewis acid in the conductor material of the conductor strand.

[0011] According to the second embodiment, the intercalant is at least one metal chloride, metal bromide, or metal iodide, particularly aluminum chloride (AlCl3), aluminum bromide (AlBr3), aluminum iodide (AlI3), zirconium chloride (ZrCl4), zirconium bromide (ZrBr4), iron chloride (FeCl3), magnesium chloride (MgCl2), magnesium bromide (MgBr2), or magnesium iodide (MgI2), and the metal of the metal chloride, metal bromide, or metal iodide is selected from one of Groups 2, 4, 5, 6, 8, 10, 11, 12, or 13 of the periodic table. The method according to the second embodiment has the advantage that the intercalant can be intercalated into the conductor strand at a lower temperature than the method according to the first embodiment.

[0012] According to the third embodiment, the intercalant is an organic alkali metal, particularly an organic sodium compound, specifically particularly naphthalide sodium (C 10 H8Na), n-amyl sodium (C5H 11 Na) or benzyl sodium (C7H7Na), an organic potassium compound, specifically particularly benzyl potassium (C7H7K) or methyl potassium (CH3K), an organic lithium compound, specifically particularly benzyl lithium (C7H7Li), n-hexyl lithium (C6H 13They are lithium (Li), n-butyllithium (C4H9Li), and phenyllithium (C6H5Li). The method according to the third embodiment has the advantage that the intercalant can be intercalated into the conductor strands at a lower temperature than the method according to the first embodiment. Also, the method according to the third embodiment does not require an auxiliary gas such as fluorine or chlorine for intercalation. Further, in contrast to other embodiments, the third embodiment dopes n-type carbon conductors.

[0013] Advantageously, the method according to the first embodiment includes the step of adding gaseous fluorine as an auxiliary gas to the gas phase when performing intercalation in the gas phase of the reactor volume, or providing a liquid phase of fluoride ions when performing intercalation in the liquid phase of the reactor volume. Since the intercalant can penetrate the conductor material of the conductor strands more rapidly, the promotion of intercalation is achieved by this method.

[0014] Also, advantageously, the method according to the second embodiment includes the step of adding gaseous chlorine, bromine, and / or iodine as an auxiliary gas into the reactor volume when performing intercalation in the gas phase of the reactor volume. In particular, chlorine is preferably added when using a metal chloride as the intercalant, bromine is preferably added when using a metal bromide as the intercalant, or iodine is preferably added when using a metal iodide as the intercalant. The intercalant can be intercalated only in this way or can be intercalated more rapidly by the conductor material of the conductor strands, so that intercalation is enabled and / or promoted by this method.

[0015] Very advantageously, the method according to the second embodiment additionally includes a step of converting metal chlorides, metal bromides, and / or metal iodides present in the material of each carbon conductor into metal fluorides by treating the conductor strands with a fluorinating agent. The method according to the second embodiment has the advantage over the first embodiment that metal chlorides, metal bromides, or metal iodides, which are intercalants, can intercalate into the conductor strands at a lower temperature than the metal fluorides according to the first embodiment. By the conversion using the fluorinating agent, the intercalant, i.e., metal chloride, metal bromide, or metal iodide, is then in-situ converted into a metal fluoride and thus a strong Lewis acid, whereby high conductivity is achieved in the carbon conductor of the conductor strand. That is, the intercalated intercalant does not directly cause a strong increase in conductivity in the conductor material, unlike the method according to the first embodiment. This is achieved subsequently by the in-situ conversion of the intercalant using the fluorinating agent.

[0016] The fluorinating agent may particularly include XeF2, F2, perfluoroolefins or fluorinated olefins such as hexafluorobutene and hexafluoropropene, hydrochlorofluorocarbons (HCFCs) such as trichlorofluoromethane, and hydrofluorocarbons (HFCs) such as perfluorohexane, pentafluorobutane, and pentafluoropropane, and / or may particularly be present in the gas phase or transfer to the gas phase during the fluorination treatment. In particular, the treatment using the fluorinating agent is carried out at a temperature below 200 °C, thereby preventing the formation of clusters that deteriorate the conductivity of each carbon conductor from the intercalated metal chlorides, metal bromides, or metal iodides finely dispersed in the carbon conductor by diffusion.

[0017] Also advantageously, the method according to the third embodiment includes an additional step of converting the organic alkali metal present in the material of each carbon conductor into an alkali metal hydride, particularly lithium hydride (LiH), sodium hydride (NaH), or potassium hydride (KH), by heat-treating the conductor strand in a hydrogen atmosphere, particularly at a temperature of 50°C to 250°C. The method according to the third embodiment has the advantage over the first embodiment that the organic alkali metal as an intercalant can intercalate into the conductor strand at a lower temperature than the metal fluoride according to the first embodiment. The intercalation is carried out from a solvent in which the organic alkali metal is dissolved.

[0018] By reacting with hydrogen during the heat treatment, the intercalant, i.e., the organic alkali metal, is then in-situ converted into an alkali metal hydride and thus a strong Lewis base, whereby high conductivity is achieved in the carbon conductor of the conductor strand.

[0019] That is, the intercalated organic alkali metal as an intercalant does not directly cause an increase in conductivity in the conductor material, unlike the method according to the first embodiment. This is achieved subsequently by the reaction of the intercalant with hydrogen during heat treatment in a hydrogen atmosphere as an in-situ conversion into an alkali metal hydride and organic residues.

[0020] Also advantageously, the method according to one of the three embodiments includes an additional step of intercalating a hydrophobizing agent, particularly an alkane such as an aliphatic, particularly undecane, perfluorotripentylamine, perfluoroperhydrofluorene, perfluoroperhydrophenanthrene, or a polysiloxane such as particularly polymethylsiloxane, into the material of each carbon conductor, particularly in the gas phase or liquid phase. By this method, the penetration of water into the conductor strand is prevented, so that the conductor strand is not affected by water with respect to its material properties, particularly conductivity and material resistance.

[0021] Furthermore, advantageously, the method according to one of the three embodiments additionally includes a step of compressing to reduce the volume of the conductor strand in order to at least partially reverse the expansion that increases the volume of the conductor strand, for example during the intercalation of the intercalant. By this method, since the porosity and thus the conductor cross-sectional area are reduced, the conductivity of the conductor strand further increases while the conductor resistance remains unchanged.

[0022] Also, the bent-relaxed conductor strand can be arranged in the grooves of the electromechanical device with a high groove filling rate, so that the power of the electromechanical device can be increased. When the intercalation is carried out in the gas phase of the reactor volume 5, additionally, in the second step of the method, water vapor may be generated or added into the reactor volume 5. This has the advantage that the expansion that increases the volume of the conductor strand due to the intercalation of the intercalant is less than that in the method without adding water vapor.

Brief Description of the Drawings

[0023] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0024] FIG. 1 schematically shows a conductor strand 1 having at least one carbon conductor 3. In order to carry out the method according to the invention, in a first step, at least one conductor strand 1 is provided or manufactured as an intermediate product.

[0025] This conductor strand 1 is, for example, a conductor composite composed of a plurality of carbon conductors 3, for example a thread, and the carbon conductors 3 may each be a conductor film, filament or fiber. However, alternatively, the carbon conductor 3 may be a thread or conductor composite with a smaller diameter than the conductor strand 1. The carbon conductor 3 is manufactured from a carbon material such as, for example, graphite, pyrolytic graphite, graphene, graphyne and / or carbon nanotubes or compounds based thereon, such as graphene oxide.

[0026] In a second step of the method, the conductor strand 1 is introduced into the gas phase or liquid phase of the reactor volume 5 together with one or more intercalants 2 (Figure 2). The intercalant 2 is selected to be suitable for the intercalation of the conductor strand 1 into the material of at least one carbon conductor 3.

[0027] In a third step of the method, a heat treatment of the conductor strand 1 is carried out, the reactor volume 5 is brought to a process temperature for initiating the intercalation 4, and the atoms or molecules of the intercalant 2 are embedded in the material of each carbon conductor 3, for example, in the interlayer region of a multi-layer carbon structure shape, for example deposited on the carbon structure shape of the carbon conductor 3.

[0028] Figure 3 schematically shows the principle procedure of the intercalation 100, and illustrates the state in which the intercalant 2 is intercalated into the intermediate layer 4 of the carbon material formed from graphene, for example, of at least one carbon conductor 3 of the conductor strand 1. Figure 3 shows different stages of the intercalation 100, and different amounts of the intercalant 2 are intercalated into the carbon material of the carbon conductor 3.

[0029] The intercalant 2 has various embodiments, which will be described below as three different embodiments. According to the present invention, the intercalant 2 may be any one or more metal halides according to the first or second embodiment, or one or more organic alkali metals according to the third embodiment.

[0030] I. First Embodiment: Use of Metal Fluorides, Particularly Aluminum (AlF 3 ) In a first embodiment of the method according to the invention, it is contemplated to use a metal fluoride for the intercalation doping of the conductor strand 1, and the metal of the metal fluoride is selected from one of Groups 2, 4, 5, 6, 8, 10, 11, 12 or 13 of the periodic table. Examples of suitable metal fluorides are aluminum fluoride (AlF3), zirconium fluoride (ZrF4), iron fluoride (FeF3) or magnesium fluoride (MgF2). In particular, amorphous aluminum fluoride (AlF3) is a very strong Lewis acid.

[0031] When the intercalation is carried out in the gas phase of the reactor volume 5, gaseous fluorine may additionally be added to the gas phase as an auxiliary gas in the second step of the method. When the intercalation is carried out in the liquid phase of the reactor volume 5, a liquid phase containing fluoride ions may be selected.

[0032] For the intercalation, a low vacuum may be provided within the reactor volume 5. The reactor volume 5 is evacuated, for example, preferably to a maximum of 0.1 mbar, particularly preferably to a maximum of 0.01 mbar. The walls of the reactor volume 5 are configured to be resistant to the intercalant 2 and are made of, for example, nickel or copper.

[0033] In the third step of the method, the reactor volume 5 is heated to a process temperature of at least 750 °C. The process temperature is within the range of the sublimation temperature of the metal fluoride, for example, above the sublimation temperature.

[0034] Vapor-phase intercalation can be carried out, for example, near the critical point where sublimation begins, especially with the temperature varying within a range of ±20 °C to ±40 °C. This achieves a temperature variation between the sublimation and re-sublimation of the intercalant. Therefore, intercalation is carried out without forming clusters of metal fluoride crystals exceeding 10% by volume in the conductor material.

[0035] Here, it is considered that the pressure within the reactor volume 5 changes with temperature. Therefore, the pressure at room temperature is selected such that sublimation of the metal fluoride becomes possible when the target temperature is reached. Preferably, in this case, since the Lewis acid has high strength, it is intended that the intercalated aluminum fluoride is mainly amorphous.

[0036] The doping according to the first embodiment is particularly stable up to at least 300 °C, and moisture has no decomposing effect on the doping. Therefore, effective and sustainable doping is achieved.

[0037] II. Second Embodiment: Use of Metal Chlorides, Metal Bromides or Metal Iodides and Subsequent In-Situ Conversion to Metal Fluorides In addition to the above-described first embodiment in which a metal fluoride is used as the intercalant 2, at least one metal chloride, metal bromide, or metal iodide is intercalated into the carbon conductor 3 as the intercalant 2, and the metal of the metal chloride, metal bromide, or metal iodide is selected from one of Groups 2, 4, 5, 6, 8, 10, 11, 12, or 13 of the periodic table. An alternative second embodiment of the method is contemplated. Subsequently, an additional step is performed in which an in-situ conversion 200 of the metal chloride, metal bromide, and / or metal iodide to a metal fluoride is carried out by fluorination. This is schematically shown in FIG. 4.

[0038] Examples of suitable intercalants according to the second embodiment are aluminum chloride (AlCl3), aluminum bromide (AlBr3) or aluminum iodide (AlI3), zirconium chloride (ZrCl4), zirconium bromide (ZrBr4), iron chloride (FeCl3), magnesium chloride (MgCl2), magnesium bromide (MgBr2), magnesium iodide (MgI2).

[0039] When the intercalation is carried out in the gas phase of reactor volume 5, in the second step of the method, gaseous chlorine, bromine or iodine may additionally be added to reactor volume 5 as an auxiliary gas. When using a metal chloride as the intercalant 2, for example chlorine may be added, when using a metal bromide as the intercalant 2, for example bromine may be added, and when using a metal iodide as the intercalant 2, for example iodine may be added.

[0040] When the intercalation is carried out in the gas phase of reactor volume 5, additionally in the second step of the method, water vapor may be generated or added into reactor volume 5. In this way, it can be achieved that the increase in volume of the conductor strands or carbon conductors caused by the intercalation is smaller than in the method without adding water vapor.

[0041] In the fourth step of the method according to the invention, the intercalated metal chlorides, metal bromides and / or metal iodides present in the material of each carbon conductor 3 are in-situ converted into metal fluorides.

[0042] This is caused by treating the conductor strand 1 with a fluorinating agent. The fluorinating agent is selected from the group of substances including, for example, XeF2, F2, perfluoroolefins or fluorinated olefins such as hexafluorobutene and hexafluoropropene, especially hydrochlorofluorocarbons (HCFCs) such as trichlorofluoromethane, and especially hydrofluorocarbons (HFCs) such as perfluorohexane, pentafluorobutane, pentafluoropropane. The fluorinating agent is present in the gas phase in the fourth step or migrates to the gas phase in the fourth step. The treatment with the fluorinating agent is carried out, for example, at a temperature below 200 °C. In addition to this, for example, the embodiments described below are possible.

[0043] Use of Aluminum Chloride (AlCl 3 ), Aluminum Bromide (AlBr 3 ) or Aluminum Iodide (AlI 3 ) In this embodiment, in the fourth step, amorphous aluminum fluoride (AlF3) is in-situ generated in the conductor composite. The strength of amorphous aluminum fluoride (AlF3) as a Lewis acid is comparable to that of antimony fluoride (SbF5) and arsenic trifluoride (AsF3).

[0044] In one embodiment, the fluorination of aluminum chloride (AlCl3) is contemplated, and in the third step, aluminum chloride (AlCl3) is intercalated into at least one carbon conductor 3 of the conductor strand 1 as the intercalant 2.

[0045] The advantage is that the sublimation temperature at 1 bar, which is about 180 °C, is very low compared to about 1260 °C of AlF3, and since aluminum chloride (AlCl3) exists as a dimer with tetrahedral coordination in the gas phase, aluminum chloride (AlCl3) can be very easily intercalated into the carbon conductor 3.

[0046] A further advantage is that the in-situ conversion of AlCl3 to AlF3 using a fluorinating agent can be carried out at room temperature in the conductor composite. This results in the formation of amorphous AlF3 with high strength as a Lewis acid. Therefore, the conductivity of the carbon conductor 3 can be improved. Since most of the AlCl3 used is converted to AlF3, the same advantages as described above occur.

[0047] Aluminum chloride (AlCl3) and the conductor strand 1 are introduced into the sealed reactor volume 5 in the second step, and the wall 6 of the reactor volume 5 is made of, for example, nickel or copper. The atmosphere inside the reactor volume 5 is preferably replaced with an inert gas, particularly argon or helium. This is particularly done by evacuating several times to a pressure of less than 0.1 mbar and filling the vacuum with an inert gas. Alternatively, the reactor volume 5 may be inactivated by a vacuum of preferably less than 0.1 mbar, particularly preferably less than 0.01 mbar. The vacuum increases the partial pressure of AlCl3, thereby facilitating doping.

[0048] Subsequently, in the third step, a heat treatment is preferably carried out at 80 °C to 250 °C. Here, as schematically shown in FIG. 3, AlCl3 intercalates into the conductor strand 1, i.e., the conductor composite. The time of the heat treatment depends particularly on the thickness of the conductor composite and thus the diffusion length of AlCl3 determined thereby.

[0049] In the fourth step, a treatment using a fluorinating agent is carried out. In the fourth step, by fluorinating the AlCl3 intercalated into the conductor strand 1 with a fluorinating agent (FIG. 4), amorphous AlF3 of the conductor strand 1 is generated in-situ. Hereinafter, fluorine is exemplified as a fluorinating agent for converting aluminum chloride and fluorine into aluminum fluoride and chlorine.

[0050] 2AlCl3 + 3F2 → 2AlF3 + 3Cl2 Since the fluorination of AlCl3 is highly exothermic, it can be carried out at room temperature. Because these conditions during fluorination are very mild, the formed AlF3 cannot crystallize and thus, according to the present invention, remains amorphous, and particularly advantageously, it is finely distributed as single molecules and intercalated in the conductor composite. Finely distributed AlF3 as single molecules is a strong electron acceptor and causes p-type doping of the carbon conductor. Thereby, high conductivity of the carbon conductor 3 can be achieved.

[0051] Here, according to the reaction in which aluminum chloride and trichlorofluoromethane become aluminum fluoride and carbon tetrachloride, highly exothermic fluorination is carried out. AlCl3 + 3CFCl3 → AlF3 + 3CCl4 During deposition with CFCl3, the CCl4 generated in the conductor composite diffuses into CFCl3.

[0052] Instead of aluminum chloride (AlCl3) as the intercalant 2, in the third step, aluminum bromide or aluminum iodide may be intercalated into the carbon conductor or the conductor composite. For this purpose, the conductor strand 1 is heat-treated at a temperature of, for example, 220°C to 360°C in the third step. At this time, aluminum bromide and / or aluminum iodide are intercalated into the conductor composite material. The heat treatment time depends particularly on the thickness of the conductor composite and thus the diffusion length of the aluminum halide determined thereby. Since the fluorination of aluminum bromide or aluminum iodide is highly exothermic, it can be carried out at room temperature and, for example, in the case of aluminum bromide, can be carried out according to the following reaction.

[0053] AlBr3 + 3CFCl3 → AlF3 + 3CBrCl3 In this reaction, aluminum bromide and trichlorofluoromethane react to become aluminum fluoride and trichlorobromomethane.

[0054] When fluorine is used as the fluorinating agent and aluminum bromide is used as the intercalant, the following reaction occurs. 2AlBr3 + 3F2 → 2AlF3 + 3Br2 In this reaction, aluminum bromide is converted to aluminum fluoride and bromine by the action of fluorine.

[0055] Aluminum bromide or aluminum iodide intercalates very easily into carbon conductors because their boiling point temperatures of 263 °C (AlBr3) or 360 °C (AlI3) are very low compared to the sublimation temperature of AlF3 of approximately 1260 °C.

[0056] The advantage of this example is that doping with AlF3 is particularly stable up to at least 300 °C and is less affected by moisture. According to the prior art, this solves the drawback that very effective intercalation dopants volatilize at high temperatures, evaporate into the surrounding atmosphere, or are decomposed by moisture in the atmosphere when in contact with air, thereby making the doping ineffective.

[0057] Because these conditions during fluorination are very mild, the formed AlF3 cannot crystallize and thus remains amorphous according to the present invention and is finely distributed and intercalated in the conductor composite.

[0058] Subsequently, in order to remove the intercalated trichlorobromomethane (boiling point 105 °C) or CCl4 (boiling point 76.7 °C) from the conductor composite, the conductor composite may be aged, for example, at 120 °C.

[0059] Use of Zirconium Chloride (ZrCl 4 ) A further example is doping with zirconium fluoride (ZrF4). Zirconium fluoride (ZrF4) has the advantage of being one of the strongest Lewis acids when present in an amorphous state.

[0060] ZrCl4 and conductor strand 1 are introduced into reactor volume 5 in a second step, and the wall 6 of reactor volume 5 is made of, for example, nickel or copper. The atmosphere inside reactor volume 5 is replaced with an inert gas, especially such as argon or helium. This is preferably done by multiple evacuations up to a pressure of 0.1 mbar and corresponding vacuum breakings with the inert gas. Alternatively, reactor volume 5 may be inactivated by a vacuum, preferably less than 0.1 mbar, particularly preferably less than 0.01 mbar. By becoming vacuum, the sublimation temperature decreases and the partial pressure of ZrCl4 increases, thereby facilitating doping. Also, intercalation may be promoted by adding chlorine. This may be done, for example, by adding gold(III) chloride (AuCl3) or gold(III) chloride hydrate (AuCl3·H2O). Gold(III) chloride hydrate loses its water of crystallization when exceeding 100 °C. Both types of gold chloride decompose at a pressure of 1 bar when exceeding 254 °C and release chlorine.

[0061] In a third step, it is preferably heat-treated at 290 °C to 450 °C. Here, ZrCl4 intercalates into the conductor composite. The heat treatment time depends particularly on the thickness of the conductor composite and the diffusion length of ZrCl4 determined thereby.

[0062] In a fourth step, treatment with a fluorinating agent is carried out. This is especially perfluoroolefins or fluorinated olefins such as hexafluorobutene and hexafluoropropene, especially hydrochlorofluorocarbons (HCFCs) such as trichlorofluoromethane CFCl3 (boiling point start 23.7 °C) and dichlorodifluoromethane CF2Cl2 (boiling point 23.7 °C), especially hydrofluorocarbons (HFCs) such as perfluorohexane, pentafluorobutane or pentafluoropropane, or other suitable fluorine compounds such as XeF2 or F2, for example.

[0063] In the fourth step, by fluorinating zirconium chloride (ZrCl4) intercalated in the conductor strand 1 with a fluorinating agent, amorphous zirconium fluoride (ZrF4) of the conductor strand 1 is in-situ generated, which is exemplified by using fluorine as the fluorinating agent in the following reaction where zirconium chloride and fluorine are converted to zirconium fluoride and chlorine.

[0064] ZrCl4 + 2F2 → ZrF4 + 2Cl2 Since the fluorination of ZrCl4 is highly exothermic, it can be carried out at room temperature. Because these conditions during fluorination are very mild, the formed ZrF4 cannot crystallize and thus, according to the present invention, remains amorphous and, particularly advantageously, is finely distributed and intercalated as single molecules in the conductor composite. Thereby, the high conductivity of the carbon conductor 3 can be achieved.

[0065] In a further step, the conductor composite is deposited on top of liquid CFCl3 such that the conductor composite is surrounded by a high concentration of gaseous CFCl3 exceeding 30% by volume. Here, strong exothermic fluorination is carried out according to the reaction where zirconium chloride and trichlorofluoromethane become zirconium fluoride and carbon tetrachloride.

[0066] ZrCl4 + 4CFCl3 → ZrF4 + 4CCl4 Thereafter, if traces of intercalated carbon tetrachloride (boiling point 76.7 °C) that did not diffuse into trichlorofluoromethane remain, the conductor composite may be aged, for example, at 120 °C to remove it from the conductor composite.

[0067] Use of Iron Chloride (FeCl 3 ) Iron fluoride (FeF3) is a strong Lewis acid when present in amorphous or single molecule form, so doping with iron fluoride (FeF3) is also possible. For this reason, iron chloride (FeCl3) is used as the intercalant 2.

[0068] Iron(III) chloride (FeCl3) and the conductor strand are introduced into the reactor volume 5 in a second step, and the wall 6 of the reactor volume 5 is preferably made of nickel or copper. The atmosphere within the reactor volume 5 is exchanged for an inert gas, particularly argon or helium. This is preferably done by evacuating several times to a pressure of less than 0.1 mbar and then filling the vacuum with the inert gas accordingly. Alternatively, the reactor volume 5 may preferably be inactivated by a vacuum of less than 0.1 mbar, particularly preferably less than 0.01 mbar. The vacuum increases the volatility of FeCl3, thereby facilitating doping. Intercalation may also be promoted by adding chlorine. This may be done, for example, by adding gold(III) chloride (AuCl3) or gold(III) chloride hydrate (AuCl3·H2O). Gold(III) chloride hydrate loses its water of crystallization above 100 °C. Both types of gold chloride decompose with dechlorination at 1 bar above 254 °C and already at 0.1 mbar above 65 °C.

[0069] In a third step, it is preferably heat-treated at 120 °C to 300 °C. Here, FeCl3 intercalates into the conductor strand 1. The time of the heat treatment depends particularly on the thickness of the conductor strand 1 and thus on the diffusion length of FeCl3.

[0070] In a fourth step, treatment with a fluorinating agent is carried out. This is particularly a perfluoroolfin or fluorinated olefin such as hexafluorobutene or hexafluoropropene, particularly a hydrochlorofluorocarbon (HCFC) such as trichlorofluoromethane CFCl3 (boiling point onset 23.7 °C) or dichlorodifluoromethane CF2Cl2, particularly a hydrofluorocarbon (HFC) such as perfluorohexane, pentafluorobutane or pentafluoropropane, or other suitable fluorine compounds such as, for example, XeF2 or F2.

[0071] In the fourth step, by fluorinating the FeCl3 intercalated in the conductor strand with a fluorinating agent, amorphous FeF3 is in-situ generated in the conductor composite. In particular, this is done with hydrofluoric acid, as exemplified by the following reaction in which iron chloride and hydrofluoric acid are converted to iron fluoride and hydrochloric acid.

[0072] FeCl 3(s) +3HF (g) →FeF 3(s) +3HCl (g) Alternatively, fluorine may be used as the fluorinating agent (conversion of iron chloride and fluorine to iron fluoride and chlorine), which generates only half as much gas as with FeCl3.

[0073] 2FeCl 3(s) +3F 2(g) →2FeF 3(s) +3Cl 2(g) More advantageously, fluorination with trichlorofluoromethane (CFCl3) or dichlorodifluoromethane (CF2Cl2) does not generate gas, and fluorination with carbon tetrachloride (CCl4) generates a liquid that can be removed from the conductor by diffusion without expansion. This is exemplified by the fluorination with CF2Cl2 in the following reaction in which iron chloride and dichlorodifluoromethane are converted to iron fluoride and carbon tetrachloride. 2FeCl 3(s) +3CF2Cl 2(g) →2FeF 3(s) +3CCl 4(l) Fluorination with trichlorofluoromethane (CFCl3) may be carried out, for example, by immersing the conductor composite in CFCl3. The highly exothermic fluorination is carried out, especially under exclusion of moisture, according to the following reaction in which iron chloride and trichlorofluoromethane are converted to iron fluoride and carbon tetrachloride.

[0074] FeCl 3(s) +3CFCl 3(l) →FeF 3(s) +3CCl 4(l) Subsequently, when there is a trace of intercalated tetrachloromethane (boiling point 76.7 °C) that did not diffuse from the conductor composite when the conductor composite was immersed in trichloromethane, the conductor composite may be aged, for example, at 65 °C to remove it from the conductor composite.

[0075] Since the fluorination of FeCl3 is highly exothermic, it can be carried out at room temperature. Since these conditions during fluorination are very mild, the formed FeF3 cannot crystallize and thus, according to the present invention, remains amorphous and, particularly advantageously, is finely distributed and intercalated as single molecules in the conductor strand 1. Thereby, the high conductivity of the carbon conductor 3 can be achieved.

[0076] In the second step, instead of iron(III) chloride FeCl3, iron(II) chloride (FeCl2) and chlorine may be introduced into the reactor volume 5, for example, in the form of gold chloride. Here, FeCl3 is produced by converting iron(II) chloride and gold chloride into iron(III) chloride and gold according to the following reaction.

[0077] 3FeCl 2(s) +AuCl 3(s) →3FeCl 3(s) +Au (s) This iron(III) chloride is then intercalated into the carbon conductor in the third step.

[0078] Use of Magnesium Chloride, Magnesium Bromide or Magnesium Iodide In this example, in the fourth step, amorphous magnesium fluoride MgF2 is in-situ generated in the conductor composite.

[0079] In contrast, in the third step, magnesium chloride (MgCl₂), magnesium bromide (MgBr₂), or magnesium iodide (MgI₂) is intercalated into the conductor complex. Subsequently, in the fourth step, magnesium chloride (MgCl₂), magnesium bromide (MgBr₂), or magnesium iodide (MgI₂) is exemplified for magnesium chloride and is fluorinated by a fluorinating agent as shown in the following reaction using fluorine as the fluorinating agent.

[0080] MgCl₂ + F₂ → MgF₂ + Cl₂ Magnesium chloride (MgCl₂), magnesium bromide (MgBr₂), and magnesium iodide (MgI₂) have melting points of 712 °C (MgCl₂), 711 °C (MgBr₂), and 637 °C (MgI₂), respectively, which are very low compared to the sublimation temperature of MgF₂ of approximately 1256 °C. Therefore, they are very easily intercalated into the conductor complex having a carbon conductor. Furthermore, especially by chlorine, intercalation into the conductor complex at a temperature below the melting point temperature of the metal halide becomes possible. A further advantage is that the in-situ conversion of magnesium chloride (MgCl₂), magnesium bromide (MgBr₂), or magnesium iodide (MgI₂) to MgF₂ in the conductor complex is carried out by a fluorinating agent at room temperature. At this time, amorphous MgF₂, which is a strong Lewis acid, is generated. A further advantage is that doping with MgF₂ is stable especially up to at least 350 °C and is not affected by moisture.

[0081] By doping MgF₂ with a fluoride of the formula MF₃, the acidity of MgF₂ can be increased to the strength of antimony pentafluoride (SbF₅) and arsenic trifluoride (AsF₃). According to the present invention, this is achieved by intercalating, in addition to magnesium halide, at least one further halide of the formula MX₃ (where M represents a metal in the +3 oxidation state such as iron (Fe), aluminum (Al), vanadium (V), chromium (Cr), indium (In) and gallium (Ga), and X represents chlorine, bromine and / or iodine) into the conductor complex and, in the fluorination step, converting, for example, magnesium chloride according to the following reaction, into fluoride as well.

[0082] 15MgCl₂ + VCl₃ + 2AlCl₃ + FeCl₃ + 21F₂ → 15MgF₂ + VF₃ + 2AlF₃ + FeF₃ + 21Cl₂

[0083] III. Third Embodiment: Use of Organic Alkali Metals and Subsequent In-Situ Conversion to Alkali Metal Hydrides In a third embodiment, the intercalant is an organic alkali metal, such as an organic sodium compound, in particular naphthalidonatodium (C 10 H₈Na), n - amylsodium (C₅H 11 Na) or benzylsodium (C₇H₇Na). Alternatively, an organic potassium compound, in particular benzylpotassium (C₇H₇K) or methylpotassium (CH₃K), or an organic lithium compound, in particular benzyllithium (C₇H₇Li), n - hexyllithium (C₆H 13 Li), n - butyllithium (C₄H₉Li) and phenyllithium (C₆H₅Li) may be provided.

[0084] In a second step, conductor strand 1 and the organic alkali metal dissolved in a solvent are introduced into reaction volume 5. Here, conductor strand 1 is immersed in the solvent. In a third step, conductor strand 1 and the organic alkali metal dissolved in a solvent are heat - treated at a mild temperature from room temperature to 200 °C, whereby the organic alkali metal intercalates into the carbon conductor of the conductor strand.

[0085] In the fourth step, similar to the second embodiment, it is contemplated that the organic alkali metal present in the material of each carbon conductor is in-situ converted to an alkali metal hydride, such as lithium hydride (LiH), sodium hydride (NaH) or potassium hydride (KH). Different from the second embodiment, this is done by heat-treating the conductor strand 1 in a hydrogen atmosphere, for example at a temperature of 50 °C to 250 °C.

[0086] After manufacturing the conductor strand according to one of the three embodiments, as a fifth step, it may be contemplated to intercalate a hydrophobizing agent into the material of the carbon conductor or the conductor strand 1, for example in the gas phase or the liquid phase. The hydrophobizing agent may be, for example, an alkane such as an aliphatic, especially undecane, perfluorotripentylamine, perfluoroperhydrofluorene, perfluoroperhydrophenanthrene, or a polysiloxane such as especially polymethylsiloxane.

[0087] Furthermore, after manufacturing the carbon conductor or the conductor strand according to one of the three embodiments, it may be contemplated to compress the conductor strand 1.

Claims

1. A method for manufacturing a conductive conductor strand (1) comprising at least one carbon conductor (3), a) manufacturing or providing a conductor strand (1) as an intermediate product comprising at least one carbon conductor (3) comprising graphite, pyrolytic graphite, graphene, graphyne and / or carbon nanotubes; b) introducing the conductor strand (1) and one or more intercalants (2) into the gas phase or liquid phase of a reactor volume (5), wherein the intercalant is suitable for intercalation into the material of the at least one carbon conductor (3) of the conductor strand (1); c) performing a heat treatment of the conductor strand (1), wherein the reactor volume (5) is brought to a process temperature for initiating intercalation (4), and atoms or molecules of the intercalant (2) are embedded into the material of each of the carbon conductors (3) in the interlayer region of the multi-layer carbon structure shape; having, the method being - additionally comprising the step of converting a metal chloride, metal bromide or metal iodide as the intercalant (2) present in the material of each of the carbon conductors into a metal fluoride by treating the conductor strand (1) with a fluorinating agent.

2. A method for manufacturing a conductive conductor strand (1) comprising at least one carbon conductor (3), a) manufacturing or providing a conductor strand (1) as an intermediate product comprising at least one carbon conductor (3) comprising graphite, pyrolytic graphite, graphene, graphyne and / or carbon nanotubes; b) introducing the conductor strand (1) and one or more intercalants (2) into the gas phase or liquid phase of a reactor volume (5), wherein the intercalant is suitable for intercalation into the material of the at least one carbon conductor (3) of the conductor strand (1); c) performing a heat treatment of the conductor strand (1), wherein the reactor volume (5) is brought to a process temperature for initiating the intercalation (4), and atoms or molecules of the intercalant (2) are embedded in the material of each of the carbon conductors (3) in the interlayer region of the multilayer carbon structure shape; having, the method being - additionally comprising the step of converting an organic alkali metal as the intercalant (2) present in the material of each of the carbon conductors into an alkali metal hydride by heat-treating the conductor strand (1) in a hydrogen atmosphere. **Claim 3** The method according to claim 1, wherein the intercalant (2) is a metal chloride, a metal bromide or a metal iodide, and the metal of the metal chloride, the metal bromide or the metal iodide is selected from one of Groups 2, 4, 5, 6, 8, 10, 11, 12 or 13 of the periodic table. **Claim 4** The intercalant (2) is an organic alkali metal selected from the group consisting of an organic sodium compound, an organic potassium compound, and an organic lithium compound, characterized in that, the method according to claim 2. **Claim 5** The method, in step b), - when performing intercalation in the gas phase of the reactor volume, adding gaseous fluorine to the gas phase, or - when performing intercalation in the liquid phase of the reactor volume, providing a liquid phase of fluoride ions, characterized by comprising the method according to any one of claims 1 or 2. **Claim 6** The method, in step b), when performing intercalation in the gas phase of the reactor volume, - When using a metal chloride as the intercalant (2), a step of adding chlorine; - When using a metal bromide as the intercalant (2), a step of adding bromine; - When using a metal iodide as the intercalant (2), a step of adding iodine; The method according to any one of claims 1 or 3, characterized by comprising the above.

7. The treatment using the fluorinating agent is carried out at a temperature of less than 200°C; The method according to any one of claims 1, 3 or 6, characterized by the above.

8. The heat treatment of the conductor strand (1) in the hydrogen atmosphere is carried out at a temperature of 50°C to 250°C; The method according to any one of claims 2 or 4, characterized by the above.

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