Method for manufacturing a conductive composite material for batteries and a conductive composite material

Abstract

The invention relates to a method for manufacturing a conductive composite material for a battery, particularly a solid-state battery, etc., comprising: - providing an ion-conducting electrolyte matrix that can be plasticized — the ion-conducting electrolyte matrix comprises: - at least one first ion-conducting material, particularly a conductive salt and particularly a plasticizable base material in the form of a polymer, and / or - at least one polymer electrolyte —; - providing a second ion-conducting material in the form of ion-conducting particles; - introducing ion-conducting particles into the electrolyte matrix to produce a mixture comprising ion-conducting particles and an electrolyte matrix; and - homogenizing the mixture, wherein the mixture is homogenized using at least one method selected from the list of kneading, extruding, and / or rolling using a homogenizing device.

Description

Background Technology

[0001] The invention relates to a method for manufacturing a conductive composite material for a battery, particularly a solid-state battery, and comprises the following steps:

[0002] - A step of providing a plasticizable ion-conducting electrolyte matrix — the ion-conducting electrolyte matrix comprises at least one first ion-conducting material, in particular a conductive salt and a plasticizable base material in particular a polymeric form, and / or at least one polymeric electrolyte — ,

[0003] - A step of providing a second ion-conducting material in the form of ion-conducting particles;

[0004] - A step of introducing ion-conducting particles into an electrolyte matrix to create a mixture composed of ion-conducting particles and an electrolyte matrix; and

[0005] - Step of homogenizing the mixture

[0006] The invention also relates to a conductive composite material for batteries, particularly all-solid-state batteries.

[0007] The invention also relates to a battery comprising a conductive composite material, in particular to an all-solid-state battery.

[0008] The present invention may generally be applied to any first ion-conducting material, but the present invention is described with reference to lithium bis(trifluoromethane)sulfonimide (LiTFSI) as the first ion-conducting material.

[0009] The present invention is generally applicable to any base material that can be plasticized, but the present invention is described with respect to polyethylene oxide as a plasticizable base material.

[0010] Although the present invention can generally be applied to any batteries, the present invention is described for batteries of the form of lithium-ion batteries and lithium batteries, respectively.

[0011] Batteries, particularly lithium-ion batteries, are used to supply energy to many devices, especially portable devices such as portable computers and smartphones. Meanwhile, lithium-ion batteries are also used in electric vehicles to power the drive. Although known traditional lithium-ion batteries have high energy densities, the energy storage possible with known lithium-ion batteries in the automotive sector is too small to match that of combustion engines in terms of range and safety. Specifications regarding the design space and weight of batteries within vehicles limit the possible energy storage capacity. Since known lithium-ion batteries are already close to their maximum theoretical energy densities, further increases in storage capacity are, on the one hand, extremely limited, and on the other hand, even if they are possible, require a very significant effort.

[0012] Accordingly, the object of the present invention is to specify a method for manufacturing a conductive composite material for a battery that has high energy density, is easy to manufacture or carry, and is inexpensive, a conductive composite material, and a battery including the conductive composite material.

[0013] Another objective of the present invention is to specify an alternative method for manufacturing a conductive composite material for a battery, an alternative conductive composite material, and an alternative battery including the conductive composite material.

[0014] In an embodiment, the present invention achieves the aforementioned objectives by a method for manufacturing a conductive composite material for a battery, particularly an all-solid-state battery, etc., and the method comprises the following steps:

[0015] - A step of providing a plasticizable ion-conducting electrolyte matrix — the ion-conducting electrolyte matrix is:

[0016] - At least one first ion-conducting material, in particular a conductive salt and a plasticizable base material in particular a polymeric form, and / or

[0017] - At least one polymer electrolyte

[0018] Includes ― ;

[0019] - A step of providing a second ion-conducting material in the form of ion-conducting particles;

[0020] - A step of introducing ion-conducting particles into an electrolyte matrix to create a mixture composed of ion-conducting particles and an electrolyte matrix; and

[0021] - Step of homogenizing the mixture

[0022] Includes,

[0023] Homogenization of the mixture is performed by at least one method selected from the list of kneading, extruding, and / or rolling using a homogenization device.

[0024] In additional embodiments, the present invention solves the aforementioned objectives by a conductive composite material for a battery, particularly an all-solid-state battery, etc., preferably manufactured using a method according to any one of claims 1 to 16, wherein the conductive composite material is:

[0025] - Plasticizable ion-conducting electrolyte matrix ― The ion-conducting electrolyte matrix is:

[0026] - At least one base material capable of plasticization, at least one first ion-conducting material, in particular a conductive salt, and / or

[0027] - At least one polymer electrolyte

[0028] Includes ― ;

[0029] and at least one second ion-conducting material in the form of ion-conducting particles

[0030] The ion-conducting particles in the electrolyte matrix are homogenized such that, with respect to one another, at least 90% of all ion-conducting particles, preferably at least 95% of all ion-conducting particles, have a minimum separation distance of at least 100 nm, preferably at least 150 nm, particularly at least 175 nm, preferably at least 200 nm, and / or the particle filling degree of the ion-conducting particles is at least 1 volume%, preferably at least 1.5 volume%, particularly at least 2 volume% with respect to the total volume of the electrolyte matrix.

[0031] In a further embodiment, the present invention solves the aforementioned objectives by a battery, in particular an all-solid-state battery comprising a conductive composite material according to any one of claims 17 to 20.

[0032] Particularly in the detailed description and preferably in the claims, the term all-solid-state battery is understood to mean a rechargeable battery in which the electrodes and the electrolyte are made of solid material.

[0033] Particularly in the detailed description and preferably in the claims, the term lithium-ion battery is understood to mean a rechargeable battery based on lithium compounds in all three phases of an electrochemical cell.

[0034] In particular, in the detailed description and preferably in the claims, the lithium battery, also referred to as a post-lithium-ion battery, is understood to mean a primary battery in which lithium or a subsequent material is used as an active material at the negative electrode.

[0035] Particularly in the detailed description, and preferably, the term "polymer electrolyte" is understood to mean a polymer having ionic dissociable groups on each repeating unit. Polypolymer electrolytes can be classified into polyacids and polybases. Polyanions are formed from inorganic or organic polyacids during dissociation by removing protons, and polycations are formed from polybases. The term "polymer electrolyte" also includes polymers containing charged metal complexes as substituents.

[0036] One of the advantages is that the ionic conductivity of the conductive composite material can be dramatically increased, which can ultimately increase the maximum possible power capacity of the battery. Another advantage is that the manufacturing method can be performed simply and inexpensively. In contrast to methods known from the prior art, the methods according to the embodiments of the present invention can provide the advantage of not using a solvent and not leaving a solvent residue in the material.

[0037] According to a preferred embodiment, the mixture is actively heated and / or cooled within a homogenization device to provide at least essentially a constant temperature and a plasticizable state of the electrolyte for at least one predetermined period. The advantage of active heating or active cooling is that a substantially constant temperature of the mixture can be maintained during homogenization, which improves the homogenization of the mixture using the methods mentioned.

[0038] According to a further preferred embodiment, before and / or during the introduction of ion-conducting particles into the electrolyte matrix, the electrolyte matrix becomes plastic and is homogenized, in particular, kneaded by a homogenization device. The advantage of this is that a much faster and more uniform distribution of ion-conducting particles in the electrolyte matrix is ​​achieved.

[0039] According to a further preferred embodiment, the electrolyte matrix is ​​prepared in particle form before homogenization, and at least one dispersion mixing operation of the mixture particles is performed. One of the advantages achieved in this way is that further improvement in the homogenization of the mixture can be achieved.

[0040] According to a further preferred embodiment, at least one dispersive mixing operation is performed at a lower temperature than the homogenization of the mixture. The advantage of this is that, on the one hand, energy is saved and on the other hand, a more uniform particle mixture is provided, which substantially improves the conductivity of the conductive composite material.

[0041] According to a further preferred embodiment, the homogenization of the mixture is performed for a period of less than 8 hours, preferably less than 5 hours, particularly preferably less than 2 hours, particularly less than 1 hour, preferably less than 0.5 hours. In this way, optimal homogenization and, at the same time, high resource efficiency are achieved.

[0042] According to a further preferred embodiment, in order to obtain a partial mixture, a first dispersion mixing operation of particles of a plasticizable base material and ion-conducting particles is first performed, and then a second dispersion mixing operation of particles of at least one ion-conducting material and particles of the partial mixture is performed. The advantage here is that by the two dispersion mixing operations, it is possible to provide a particularly homogeneous (whole) mixture and thus high conductivity of the conductive composite material in a particularly simple manner.

[0043] According to a further preferred embodiment, the ion-conducting particles are provided in the form of ceramic particles, particularly glass-ceramic particles. An advantage of ion-conducting particles in the form of ceramic particles, particularly glass-ceramic particles, is that the ceramic particles have a lower coefficient of thermal expansion than a pure polymer-based electrolyte matrix. In this regard, the difference can be tens of times. Consequently, when ion-conducting (glass-ceramic) ceramic particles are incorporated into a polymer electrolyte to form a hybrid electrolyte, the geometry of the polymer-electrolyte battery components changes much less with temperature variations. However, at the same time, flexibility is ensured, which is not the case with conventional known pure (glass-ceramic) ceramic solid electrolytes prepared by sintering. In addition, it is possible to prepare mechanically stable and thin membranes that are more resistant to the formation and penetration of harmful lithium dendrites in this manner. Another advantage is that they are electrochemically stable over a wide range and have high conductivity over a desirable temperature range, for example, at room temperature.

[0044] According to additional preferred embodiments, the ceramic particles are listed below:

[0045] - P2O5,

[0046] - TiO2,

[0047] - Cr2O3,

[0048] - Al2O3,

[0049] - Ga2O3,

[0050] - Li2O,

[0051] - Fe2O3,

[0052] - GeO2,

[0053] - ZrO2,

[0054] - Ta2O5,

[0055] - Nb2O5,

[0056] - La2O3,

[0057] - SiO2,

[0058] - Gd2O3,

[0059] - Y2O3,

[0060] - B2O3,

[0061] - sulfur,

[0062] - Halides, or

[0063] - Nitrogen

[0064] It is selected based on a ceramic having at least one of the materials from.

[0065] The advantage of this is increased flexibility in terms of cost, availability, and external conditions. Another advantage is that ceramic particles containing these materials are more resistant to the effects of water or moisture and are mostly inexpensive.

[0066] According to a further preferred embodiment, the ceramic particles are provided in the form of lithium-based glass-ceramic particles. The advantage of lithium-based glass-ceramic particles is that they have high conductivity at room temperature and are electrochemically stable at the same time. The number of ion transfers of lithium ions is 1, whereas for conventional polymer electrolytes, the number of ion transfers is generally much lower than 0.5: that is, the measured conductivity is 100% due to lithium ion transport in the former case and less than 50% in the latter case.

[0067] According to a further preferred embodiment, lithium-based glass-ceramic particles are the following ion conductors:

[0068] - Ionic conductors having a garnet structure, preferably lithium lanthanum zirconium oxide (LLZO),

[0069] - Ion conductors having a NaSICon structure, preferably lithium aluminum titanium phosphate (LATP) or lithium aluminum germanium phosphate (LAGP) or mixed oxides thereof,

[0070] - Ionic conductors having a perovskite structure, preferably lithium lanthanum titanate (LLT),

[0071] - Ionic conductors having a spinel structure, and / or

[0072] - Ionic conductors having a LiSICon structure, preferably lithium zinc germanate

[0073] Includes at least one of the following,

[0074] A plasticizable base material comprising polyethylene oxide is prepared. One of the advantages achieved by this is that a simple conductive composite material is provided that is electrochemically stable and has high conductivity at room temperature. Additionally, increased mechanical flexibility is provided, which is advantageous for the production of cell / battery components (e.g., via a roll-to-roll method). Meanwhile, geometric changes in the cells and the resulting stresses, which are inevitably associated with volume changes in the active materials of the cathode and anode during charging and discharging in daily operation, can be mechanically compensated to a significant extent. This increases reliability during operation. Therefore, the conductive composite material provided in this manner, particularly the hybrid electrolyte, possesses increased conductivity and electrochemical stability on the one hand, and the superior mechanical flexibility of its polymer-based counterpart on the other.

[0075] According to additional preferred embodiments, the first ion-conducting material has the following list:

[0076] - Lithium salts of sulfonyl imides, preferably LiN(FSO2)2(LiFSI), LiN(SO2CF3)2(LiTFSI), and / or LiN(SO2C2F5)2(LiBETI)

[0077] - LiAsF6,

[0078] - LiClO4,

[0079] - LiSbF6,

[0080] - LiPtCl6,

[0081] - LiAlCl4,

[0082] - LiGaCl4,

[0083] - LiSCN,

[0084] - LiAlO4,

[0085] - LiCF3CF2SO3,

[0086] - Li(CF3)SO3(LiTf),

[0087] - LiC(SO2CF3)3,

[0088] - Phosphate-based lithium salts, preferably LiPF6, LiPF3(CF3)3(LiFAP), and LiPF4(C2O4)(LiTFOB),

[0089] - Borate-based lithium salts, preferably LiBF4, LiB(C2O4)2(LiBOB), LiBF2(C2O4)(LiDFOB), LiB(C2O4)(C3O4)(LIMOB), Li(C2F5BF3)(LiFAB), and Li2B 12 F 12 (LiDFB),

[0090] - Lithium salts of sulfonyl imides, preferably LiN(FSO2)2(LiFSI), LiN(SO2CF3)2(LiTFSI), and / or LiN(SO2C2F5)2(LiBETI)

[0091] At least one conductive salt selected from is prepared.

[0092] The advantage of this is that flexibility increases in terms of cost, usage, and external conditions.

[0093] According to a further preferred embodiment, the anions of the lithium salts are PF6-, BF4-, SbF6-, AsF6-, C4F9SO3-, ClO4-, AlO2-, AlCl4-, (C x F 2x+1 Selected from the group including SO3)- where 0 <= x < 1, and / or (C xF2 x+1 SO2) (C y F 2y+1 Selected from the group including SO2)N-, where 0 <= x < 1 and 0 <= y < 1. This makes it possible to select or combine various anions. The advantage of this is that flexibility is increased in terms of cost, availability, and external conditions.

[0094] According to a further preferred embodiment, the lithium salt is LiClO4, LiB F4 , is selected from the group comprising lithium bis(oxalate)borate, lithium difluoro(oxalate)borate, LiSO3CF3, lithium 2-penta-fluoroethoxy-1,1,2,2-tetrafluoroethanesulfonate, LiN(FSO2)2 and / or LiN(SO2CF3)2, lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium bis(oxalato)borate (LiBOB), lithium difluoro(oxalate)borate (LiDFOB), LiSO3CF3 (LiTf), lithium 2-pentafluoroethoxy-1,1,2,2-tetrafluoroethanesulfonate (LiSO3C2F4OC2F5), lithium bis(fluorosulfonyl)imide (LiN(FSO2)2 (LiFSI), and lithium bis(trifluoromethane)sulfonimide (LiN(SO2CF3)2 (LiTFSI). thereby It is also possible to combine or select various materials. The advantage of this is increased flexibility in terms of cost, availability, and external conditions.

[0095] According to a further preferred embodiment, the ion-conducting particles and the particles of the electrolyte matrix are dried in advance. One of the advantages obtained from this is that water remaining on the surface of the particles is removed, thereby preventing adhesion during the dispersion mixing operation and enabling effective mixing. Another advantage is that this reduces the likelihood of elemental hydrogen formation in the battery, which significantly reduces battery damage caused by gaseous hydrogen resulting from, for example, undesirable battery expansion. In this way, the reliability of the battery is increased.

[0096] According to a further preferred embodiment, ion-conducting particles are introduced into the electrolyte matrix in a volume percentage of 1% to 30%, particularly 2% to 20%, preferably 3% to 10%, particularly 4% to 9%. The advantage of this is the effective use of ion-conducting particles in the conductive composite material to provide high conductivity. Another advantage is the flexible handling of the conductive composite material and excellent production processability in terms of production engineering.

[0097] According to a further preferred embodiment of the conductive composite material, the ion-conducting particles are glass-ceramic particles, in particular lithium-based glass-ceramic particles, preferably lithium aluminum titanium phosphate particles and / or lithium lanthanum zirconium oxide particles. One of the advantages achieved by this is that a simple conductive composite material having high conductivity at room temperature while being electrochemically stable is provided.

[0098] According to a further preferred embodiment of the conductive composite material, the plasticizable base material comprises at least one polymer, in particular polyethylene oxide. As at least one polymer, e.g., polyethylene carbonate (PEC), polypropylene carbonate (PPC), polycaprolactone (PCL), polyacrylonitrile, polyester, polypropylene oxide, ethylene oxide / propylene oxide copolymer, polyethylene oxide cross-linked with trifunctional urethane, poly(bis(methoxy-ethoxy-ethoxide))-phosphazene (MEEP), triol-type polyethylene oxide cross-linked with difunctional urethane, poly((oligo)oxyethylene) methacrylate-co-alkali metal methacrylate, polymethyl methacrylate (PMMA), polymethylacrylonitrile (PMAN), polysiloxane and copolymers and derivatives thereof, polyvinylidene fluoride or polyvinylidene chloride and copolymers and derivatives thereof, poly(chlorotrifluoroethylene), poly(ethylene-chlorotrifluoroethylene), poly(fluorinated ethylene-propylene), acrylate-based polymers, It is possible to use their condensed or cross-linked combinations and / or physical mixtures thereof individually or in combination. The advantage of this is increased flexibility in terms of cost, availability, and external conditions.

[0099] Additional important features and advantages of the invention come from the dependent claims, drawings, and the associated drawing description based on the drawings.

[0100] It is evident that the features mentioned above and the features still described below may be used in the combinations specified in each case, as well as in other combinations or as themselves, without departing from the scope of the present invention.

[0101] Preferred embodiments and examples of the present invention are illustrated in the drawings and will be described in detail in the following description, and like reference numerals indicate like or functionally like components or elements.

[0102] Accordingly, the following is described: Brief explanation of the drawing

[0103] FIG. 1 is a diagram showing the conductivity of a known conductive material during heating (Fig. 1a) and during cooling (Fig. 1b), and the conductivity of a conductive material according to an embodiment of the present invention; FIG. 2 is a diagram showing the conductivity of a known conductive material during heating (Fig. 2a) and during cooling (Fig. 2b), and the conductivity of a conductive material according to an embodiment of the present invention; FIG. 3 is a diagram showing the ratio of conductivity after the use of a tumbling or kneading process according to the particle filling degree of two different ion-conducting particles according to an embodiment of the present invention; FIG. 4 is a diagram showing the conductivity of LLZO-type ion-conducting particles measured after the use of a tumbling or kneading process according to the degree of particle filling according to an embodiment of the present invention; FIG. 5 is a diagram showing the conductivity of ion-conducting particles in the form of LATP after use of a tumbling or kneading process according to the degree of particle filling according to an embodiment of the present invention; FIG. 6 shows the steps of a method according to an embodiment of the present invention. Specific details for implementing the invention

[0104] To measure the respective conductivity, sintered discs of LLZO and LATP materials in powder form were first fabricated, and the contact resistance between the PEO-LiTFSi membrane and each disc was measured. Subsequently, ionic conductivity was measured in relation to different volume fractions of the ion-conducting particles LATP and LLZO. The conductivity of the hybrid electrolytes obtained in this way was compared with that of a non-conductive SiO2-based polymer material.

[0105] Experiments

[0106] Raw materials:

[0107] Specifically, Li7La3Zr2O 12 - LLZO - Powder and Li 1.3 Al 0.3 Ti 1.7 P3O 12 - LATP - Powders were manufactured using known industrial methods. As a result, the powders possess both an amorphous phase and a highly conductive crystalline phase in the core. The amorphous phase can support lithium-ion-based conductivity and also improve compatibility with the respective polymers. The amorphous phase also improves the density of the material compared to pure crystalline materials.

[0108] For the following experiments, the density is 4.9 g / cm³ 3 Phosphorus LLZO particles and a density of 2.9 g / cm³ 3 LATP was used. In particular, since LLZO particles are highly hygroscopic, experiments were conducted in a drying room or under an inert gas such as an argon-filled container or glove box. Preferably, the conductive salt and polymer are also hygroscopic.

[0109] Although the same polymer matrix was used as a standard, AEROSIL from manufacturer Evonik ® Hydrophobic pyrolytic silica gel obtained from R 812 S was replaced, bonded, or mixed with non-conductive particulate filler material. The surface area measured by the BET method was 195 m². 2 / g to 245 m 2 / g. SiO2 nanoparticles have a moisture content of 0.5% and a carbon content of 3.0% to 4.0%.

[0110] Molecular formula H(C2H4O) nAs a plasticizable base material having OH (abbreviated as PEO), polyethylene oxide was sourced from the manufacturer Dow as POLYOX WSR 205, with a molecular weight of 600,000 g / mol. Lithium bis(trifluoromethane)sulfonimide (LiN(SO2CF3)2LiTFSI) was sourced from the manufacturer Solvionik and used as a polymer electrolyte or first ion-conducting material.

[0111] Ambient conditions during processing:

[0112] All dispersion mixing processes were performed as dry mixing processes in a drying chamber at a temperature of approximately 20°C and a dew point of -45°C to -55°C. Prior to mixing all components, they were dried in a vacuum chamber at 40°C for several hours to ensure that any residual moisture that may remain on the surface of the particles was removed.

[0113] Preparation and Characterization of Sandwich-Type Complex Electrolytes:

[0114] In addition, to prepare homogeneous and dense discs, pellets from LLZO and LATP particles were compressed and then sintered. The discs were polished using SIC#3600 abrasive paper. Subsequently, PEO-LiTFSI membranes and copper foil electrodes were arranged on both sides of each disc to prepare a sandwich-type composite electrolyte. Thus, to obtain a uniform electric field, the diameters of the polymer membranes and copper foil electrodes were adjusted to match the diameters of the discs. Subsequently, to provide good coverage or adhesion of the PEO-LiTFSI electrolyte matrix onto the sintered discs and copper foil electrodes, the sandwich-type composite electrolyte was compressed in a hydraulic press at a minimum of 150 kPa and 50 °C for several minutes. The thickness of the entire system is then measured to determine any possible reduction in open porosity between the PEO-LiTFSI electrolyte matrix, the sintered discs, and the copper foil electrodes. To determine the thickness of the sandwich-type composite electrolytes, the thickness of the two copper foil electrodes is subtracted.

[0115] Preparation of complex electrolytes by mixing in a tumbler and preparation for their characterization:

[0116] To homogenize the powder mixtures, all materials were pre-mixed by a dispersion mixing operation using a shaker mixture with a rotation speed of 10 to 100 revolutions per minute. Here, a WAB Model T2Z drum tumbler or shaker mixer was used. In the first step, PEO and the respective oxide filler materials, namely SiO2, LATP, or LLZO particles, were mixed for several minutes. In the second step, a conductive salt was then added and mixed for an additional few minutes to achieve a uniform distribution of the components.

[0117] To analyze ionic conductivity, each powder was compressed to form pellets with a diameter of 16 mm. A MAASEN Model MP 250 laboratory press was used for this purpose. The pressing force was set to at least 100 kN, and a pressure of at least 500 MPa was achieved.

[0118] Preparation of complex electrolytes in a kneader and preparation for their characterization:

[0119] To disperse oxide particles into the molten polymer, the powder mixture, pre-mixed by a drum tumbler mixer, was homogenized in a kneader, where a Thermo Fisher HAAKE PolyLab Rheomix 610 kneader was used. The kneader chamber was heated to over 50°C. While the oxide particles were being introduced into the kneading chamber, the rotational speed was reduced to single-digit revolutions per minute and maintained until the kneader's working volume was filled to a maximum of 50%. Subsequently, the rotational speed was increased by several rotations per minute to over 50 rpm. The total kneading time was several minutes.

[0120] Subsequently, the molten hybrid electrolyte mass was removed and calendered by a calendering device, where a laboratory calender from Saueressig was used. The calendering rolls were heated to over 100 °C, and the peripheral speed was set to less than 0.25 m / min. It was ensured that the gap between the two opposing rolls enabled self-supporting hybrid electrolyte layers with a thickness of approximately 500 micrometers. Hybrid electrolyte layers with a thickness of 16 mm were then punched using a punching device.

[0121] To measure the ionic conductivity of hybrid electrolytes containing a PEO-LITFSI electrolyte matrix and various glass-ceramic particle fillers, 16 mm diameter hybrid electrolyte discs were then inserted into standardized CR2032 type battery housing mounts. Stainless steel spacers as well as corresponding disc springs were used to maintain constant pressure within the housing during conductivity measurements. Additionally, the battery housings, along with the hybrid electrolyte discs, were then heated to over 70°C using a BINDER oven to prevent crystallization of the PEO in the electrolyte matrix, i.e., to obtain reproducible results.

[0122] Measurement parameters during characterization:

[0123] To record the measured values, potentiostatic electrochemical impedance spectroscopy was performed using instruments from ZAHNER and ZEHNIUM with a voltage amplitude of 10 mV and a frequency of 0.1 to 4 x 10⁻⁶ 7 It was used in Hz. To determine the plot, the software RelaxIS 3 for RHD instruments was used.

[0124] To determine particle size, X-ray diffraction measurements were performed using a Panalytical X'Pert Pro MPD diffractometer, and the results were refined using the same company's HighScorePlus software. Slices of the discs were prepared, and corresponding images were recorded at voltages of 15 kV to 20 kV using a ZEISS Model NEO 40 scanning electron microscope. Subsequently, the particle size distribution was determined using a 3P Instruments Cilas 1064.

[0125] Reference without application of (glass-ceramic) ceramic ion conductor particles:

[0126] To prevent the occurrence of accumulation or "aggregation" of the PEO-LiTFSI electrolyte matrix, a small amount of non-conductive SiO2 nanoparticles were added for comparison—as already discussed above—and used as a reference for comparison with conductive particles LLZO and LATP.

[0127] Experimental results

[0128] FIG. 1 is a diagram showing the conductivity of a known conductive material during heating (Fig. 1a) and during cooling (Fig. 1b), and the conductivity of a conductive material according to an embodiment of the present invention;

[0129] In detail, FIG. 1 shows absolute conductivity in S / cm units plotted against temperature (upper horizontal axis in each case) and inverse temperature (lower horizontal axis in each case) in partial FIG. 1a and FIG. 1b. Accordingly, the reference numbers are designated as follows:

[0130] - Reference number 104 specifies a plot curve of conductivity for a PEO-LiTFSI electrolyte matrix containing 2.2 volume% SiO2 as a filler material together with copper electrodes, as a reference to a known ion-conducting composite material in the form of a membrane—hereinafter referred to as the reference membrane.

[0131] - Reference number 103 specifies the theoretical plot-type curve of conductivity for a PEO-LATP-PEO composite material having copper electrodes.

[0132] - Reference number 102 specifies a measured plot curve of conductivity for a PEO-LATP-PEO composite material having copper electrodes.

[0133] - Reference number 101 specifies the measured plot curve of conductivity for a sintered LATP disk having gold electrodes.

[0134] Thus, FIG. 1a describes a plot of each conductivity during the heating process, and FIG. 1b describes a plot of each conductivity during the cooling process. Since the PEO of the electrolyte matrix tends to undergo crystallization below its melting point, the impedance spectra or conductivity of FIG. 1a and FIG. 1b were recorded individually. The corresponding uncertainty of the polymer conductivity is visually rendered by the corresponding broad curve (104). The error bars (101, 102, 103) of the conductivity reach less than 5% at each measurement point.

[0135] FIG. 2 illustrates the conductivity of a known conductive material during heating (Fig. 2a) and during cooling (Fig. 2b), and the conductivity of a conductive material according to an embodiment of the present invention.

[0136] In detail, FIG. 2 shows temperature-dependent absolute conductivity in S / cm units plotted against temperature (upper horizontal axis in each case) and inverse temperature (lower horizontal axis in each case) in partial FIG. 2a and FIG. 1b. Accordingly, the reference numbers are designated as follows:

[0137] - Reference number 104 refers to a known ion-conducting composite material in the form of a membrane—hereinafter referred to as the reference membrane—and specifies a plot curve of conductivity for a PEO-LiTFSI electrolyte matrix containing 2.2 volume% SiO2 as a filling material together with copper electrodes.

[0138] - Reference number 103 specifies the theoretical plot-type curve of conductivity for a PEO-LLZO-PEO composite material having copper electrodes.

[0139] - Reference number 102 specifies the measured plot curve of conductivity for a PEO-LLZO-PEO composite material having copper electrodes.

[0140] - Reference number 101 specifies the measured plot curve of conductivity for a sintered LLZO disk having gold electrodes.

[0141] Thus, FIG. 2a describes a temperature-dependent plot of each conductivity during the heating process, and FIG. 2b describes a plot of each conductivity during the cooling process. Since the PEO of the electrolyte matrix tends to undergo crystallization below its melting point, the impedance spectra or conductivity of FIG. 2a and FIG. 2b were recorded individually. The corresponding uncertainty in the conductivity of the polymer is visually rendered by the corresponding broad curve (104). The error bars (101, 102, 103) of the conductivity reach less than 5% at each measurement point.

[0142] FIG. 3 illustrates a diagram showing the ratio of conductivity after each use of a tumbling process or a kneading process following a tumbling process, according to the particle filling degree of two different ion-conducting particles according to an embodiment of the present invention.

[0143] Specifically, FIG. 3 illustrates a comparison of conductivity ratios according to the degree of filling of LATP and LLZO into the PEO-LiTFSi electrolyte matrix, which were mixed once by a kneading process and once by a tumbling process, respectively. In the case of the tumbling process, conductivity measurements were performed after 72 hours at 80°C to enable proper homogenization and connection with the electrodes.

[0144] Thus, a comparison of curves 200 and 201 shows that when the degree of filling is the same and the same mixing process—kneading or tumbling—is used, the addition of LLZO particles essentially provides substantially higher conductivity in the conductive composite material than the addition of LATP particles, starting from 2 volume%. Ultimately, a comparison of the ratios of conductivity in terms of each mixing process shows that kneading enables substantially higher conductivity than the tumbling mixing process over the entire range of 0 to 20 volume% shown here.

[0145] FIG. 4 illustrates a diagram of the measured conductivity of a conductive composite material for the addition of LLZO particles after the use of a tumbling process or a kneading process according to the degree of particle filling according to an embodiment of the present invention, and FIG. 5 illustrates a diagram showing the measured conductivity of a conductive composite material for the addition of LATP particles after the use of a tumbling process or a kneading process according to the degree of particle filling according to an embodiment of the present invention.

[0146] Specifically, FIG. 4 shows the measured absolute conductivity for a conductive composite material provided with LLZO particles mixed into a PEO-LiTFSi matrix of the composite material by a kneading process and a tumbling mixing process, and FIG. 5 shows the measured absolute conductivity corresponding to LATP particles.

[0147] When LATP particles are used and when LLZO particles are used, the conductivity (301) achieved when the kneading mixing process is used is higher than when the tumbling mixing process is used (Ref. 300). In contrast to the use of LLZO particles in FIG. 4, even when the tumbling mixing process is used, the conductivity (300) initially increases to a maximum of 5 volume% and then drops above that, whereas when the kneading process is used, the conductivity (301) further increases to a maximum of 10 volume% and then drops.

[0148] FIG. 6 illustrates the steps of a method according to an embodiment of the present invention.

[0149] In detail, FIG. 6 illustrates a method for manufacturing a conductive composite material for batteries, particularly solid-state batteries.

[0150] Thus, the method includes the following steps:

[0151] In the first step (S1), a plasticizable ion-conducting electrolyte matrix is ​​provided, and the ion-conducting electrolyte matrix comprises at least one first ion-conducting material, in particular a conductive salt and a plasticizable base material in particular a polymeric form. Alternatively or additionally, at least one polymeric electrolyte may form the electrolyte matrix.

[0152] In an additional step (S2), a second ion-conducting material is provided in the form of ion-conducting particles.

[0153] In an additional step (S3), ion-conducting particles are introduced into an electrolyte matrix to create a mixture consisting of ion-conducting particles and an electrolyte matrix.

[0154] In an additional step (S4), the mixture is homogenized, and the mixture is homogenized by at least one method selected from the list of kneading, extruding, and / or rolling using a homogenization device.

[0155] In summary, at least one of the embodiments of the invention has at least one of the following advantages:

[0156] - Excellent homogenization of ion-conducting particles in the electrolyte matrix.

[0157] - High conductivity, especially conductivity twice as high as the standard including non-conductive filler materials.

[0158] - Especially simple production without additional solvents.

[0159] Although the present invention has been described based on preferred exemplary embodiments, it is not limited thereto and can be modified in various ways. Explanation of the symbols

[0160] 101 Plot-type curve of conductivity 102 Plot-type curve of conductivity 103 Plot-type curve of conductivity 104 Plot-type curve of conductivity 200 Conductivity Kneader / Tumbler Ratio - LATP 201 Conductivity Kneader / Tumbler Ratio - LLZO 300 Evangelism Maps - Nieder 301 Evangelism Map - Tumblr

Claims

Claim 1 A method for manufacturing a conductive composite material for a battery, comprising: a step (S1) of providing a plasticizable ion-conducting electrolyte matrix, wherein the ion-conducting electrolyte matrix comprises: at least one first ion-conducting material and a plasticizable base material, and at least one of at least one polymer electrolyte; a step (S2) of providing a second ion-conducting material in the form of ion-conducting particles; and a step (S3) of introducing the ion-conducting particles into the electrolyte matrix to create a mixture comprising the ion-conducting particles and the electrolyte matrix. and- comprising the step (S4) of homogenizing the mixture, wherein the homogenization (S4) of the mixture is performed using at least one method selected from a list of kneading and extruding using a homogenization device, wherein the mixture is actively heated or cooled or heated and cooled within the homogenization device to provide at least a constant temperature of 50°C or more and a plasticized state of the electrolyte matrix for less than 8 hours, and wherein the ion-conducting particles in the electrolyte matrix are homogenized in such a manner that the ion-conducting particles have a minimum separation distance of at least 100 nm with respect to each other and the particle filling degree of the ion-conducting particles is at least 1 volume% with respect to the total volume of the electrolyte matrix. Claim 2 delete Claim 3 A method according to claim 1, further characterized in that, at least one of before and during the introduction of the ion-conducting particles into the electrolyte matrix, the electrolyte matrix becomes plastic and is homogenized by the homogenization device. Claim 4 A method according to claim 1, further characterized in that the homogenization of the mixture is performed for a period of less than 5 hours, or less than 2 hours, or less than 1 hour, or less than 0.5 hours. Claim 5 A method according to claim 1, further characterized in that, prior to homogenization, the electrolyte matrix is ​​provided in the form of particles and at least one dispersion mixing operation of the mixture particles is performed. Claim 6 A method according to claim 5, further characterized in that at least one shaking mixing operation is performed at a temperature lower than the homogenization temperature of the mixture. Claim 7 A method according to claim 5, further characterized in that, in order to obtain a partial mixture, a first dispersion mixing operation of particles of the plasticizable base material and the ion-conducting particles is performed first, and then a second dispersion mixing operation of particles of the at least one ion-conducting material and particles of the partial mixture is performed. Claim 8 A method according to claim 1, further characterized in that the ion-conducting particles are provided in the form of ceramic particles. Claim 9 The method according to claim 8, further characterized in that the ceramic particles are selected based on a ceramic having at least one of the following materials from the list: - P2O5, - TiO2, - Cr2O3, - Al2O3, - Ga2O3, - Li2O, - Fe2O3, - GeO2, - ZrO2, - Ta2O5, - Nb2O5, - La2O3, - SiO2, - Gd2O3, - Y2O3, - B2O3, - sulfur, - halides, - nitrogen. Claim 10 A method according to claim 8, further characterized in that the ceramic particles are provided in the form of lithium-based glass-ceramic particles. Claim 11 The method according to claim 10, wherein the lithium-based glass-ceramic particles comprise at least one of the following ion conductors: - ion conductors having a garnet structure, - ion conductors having a NaSICon structure, - ion conductors having a perovskite structure, - ion conductors having a spinel structure, and - ion conductors having a LiSICon structure, and further characterized in that the plasticizable base material comprising polyethylene oxide is provided. Claim 12 The method according to claim 1, further characterized in that the first ion-conducting material is provided with at least one conductive salt selected from the following list: lithium salts of sulfonyl imides, LiAsF6, LiClO4, LiSbF6, LiPtCl6, LiAlCl4, LiGaCl4, LiSCN, LiAlO4, LiCF3CF2SO3, Li(CF3)SO3(LiTf), LiC(SO2CF3)3, phosphate-based lithium salts, and borate-based lithium salts. Claim 13 In claim 12, the anions of the above lithium salts are PF6-, BF4-, SbF6-, AsF6-, C4F9SO3-, ClO4-, AlO2-, AlCl4-, (C x F 2x+1 A group including SO3)- (where 0 <= x < 1), and (C x F 2x+1 SO2) (C y F 2y+1 A method further characterized by being selected from at least one of the group including SO2)N- (where 0 <= x < 1 and 0 <= y < 1). Claim 14 The method according to claim 12, further characterized in that the lithium salt is selected from the group consisting of lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium bis(oxalate)borate (LiBOB), lithium difluoro(oxalate)borate (LiDFOB), LiSO3CF3 (LiTf), lithium 2-penta-fluoroethoxy-1,1,2,2-tetrafluoroethanesulfonate (LiSO3C2F4OC2F5), lithium bis(fluorosulfonyl)imide [LiN(FSO2)2, LiFSI], and lithium bis(trifluoromethane)sulfonimide [LiN(SO2CF3)2, LiTFSI]. Claim 15 A method according to claim 1, further characterized in that at least one of the ion-conducting particles and the particles of the electrolyte matrix is ​​dried in advance. Claim 16 A method according to claim 1, further characterized in that the ion-conducting particles introduced into the electrolyte matrix are provided in a volume percentage of 1% to 30%, or 2% to 20%, or 3% to 10%, or 4% to 9% in the electrolyte matrix. Claim 17 A conductive composite material for a battery manufactured using the method according to claim 1, wherein the conductive composite material comprises: a plasticizable ion-conducting electrolyte matrix ― said ion-conducting electrolyte matrix comprises: - at least one plasticizable base material, at least one first ion-conducting material, and - at least one polymer electrolyte ―; and at least one second ion-conducting material in the form of ion-conducting particles, wherein said ion-conducting particles in the electrolyte matrix are homogenized in such a manner that, with respect to one another, said ion-conducting particles have a minimum separation distance of at least 100 nm, or at least 150 nm, or at least 175 nm, or at least 200 nm, and the particle filling degree of said ion-conducting particles is at least 1 volume%, or at least 1.5 volume%, or at least 2 volume% with respect to the total volume of said electrolyte matrix. Claim 18 A conductive composite material according to claim 17, further characterized in that the ion-conducting particles include glass-ceramic particles. Claim 19 A conductive composite material according to claim 17, wherein the plasticizable base material further comprises at least one polymer. Claim 20 A conductive composite material according to claim 17, further characterized in that the ion-conducting particles introduced into the electrolyte matrix have a volume percentage of 1% to 30%, or 2% to 20%, or 5% to 10%, or 6% to 9% in the electrolyte matrix. Claim 21 A battery comprising a conductive composite material according to Clause 17. Claim 22 A method according to claim 1, characterized in that the plasticizable base material is in the form of a polymer.

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