Process for producing a dry film, system for producing a dry film, dry film, and battery containing the dry film

Abstract

The invention relates to a process for producing a dry film, a system for producing a dry film, a dry film and a battery containing the dry film. The process and the system are characterised in that at least two processing devices are used which are arranged in a direction perpendicular to a carrier roller rotational axis, in each case with respect to an outer segment of the carrier roller, wherein the at least two processing devices are suitable for removing regions of the dry film which are mounted on the carrier roller on the outer segments of the carrier roller. The process and the system make it possible to provide, in a rapid and energy-saving manner, segmented, strip-like dry films which have very precise edges.

Description

[0001] Method for producing a dry film, plant for producing a dry film, dry film and battery containing the dry film

[0002] A method for producing a dry film, a plant for producing a dry film, a dry film and a battery containing the

[0003] A dry film is provided. The method and the system are characterized in that at least two processing devices are used, each of which is arranged opposite an outer segment of the carrier roller in a direction perpendicular to the carrier roller rotation axis, wherein the at least two processing devices are each suitable for removing regions of the dry film that are mounted on the outer segments of the carrier roller. The method and the system make it possible to quickly and energy-efficiently provide segmented, strip-shaped dry films that have very high edge accuracy. It is known in the prior art to coat electrically conductive conductor foils of battery electrodes using a slurry process (i.e. wet-chemically) with a slurry film containing electrode active material, binder and conductive additive.For efficient production, increasingly wider films are coated onto the electrically conductive conductor foils used as a substrate. Coating widths are often required that are several times the width of the electrode manufactured from the substrate with film. For example, a layer width of 300 mm is listed here, with pieces of 100 mm length being cut from the film of this width to produce an electrode format of, for example, 300 mm wide x 100 mm long. For the production of electrodes with segmented coatings (zebra coating), slot dies with masks (shims) are used, for example. These allow coating over a large width and, to create uncoated areas, prevent slurry from escaping from the slot die at the masked areas.By controlling the slurry flow through the nozzle opening, so-called intermittent coatings can also be created, which have an uncoated area at regular intervals along the coating direction.

[0004] Furthermore, it is known in the prior art to coat electrically conductive conductors of battery electrodes using the dry-film process (i.e., dry-chemical or dry) with a dry film containing electrode active material, conductive additive, and binder. A dry mixture and / or a dry powder mixture containing particles of the active material, the conductive additive, and the binder is used. A dry film refers to a coating or a free-standing, self-supporting film resulting from a film-forming process in which no solvents are used. The resulting layer or film generally has a thickness in the range of 10 μm to 1000 μm and is composed of particles. A free-standing dry film has a mechanical tensile strength (nominal stress) of > 100 N / m. 2 along the layer plane, making it self-supporting. For tensile strengths (nominal stresses) < 100 N / m 2The dry film is not self-supporting and must be mechanically stabilized either by a roller, substrate film, or other devices. In the area of ​​battery electrodes, the dry film exhibits comparable properties (layer thickness, porosity, composition, conductivity) to a layer produced using the slurry process. A process for producing a dry film is highly relevant for future battery production, as it can be carried out faster and more energy-efficiently than the slurry process (e.g., evaporation of the slurry liquid is eliminated, allowing for smaller systems with lower energy requirements). However, the dry film process still has disadvantages compared to the slurry process.

[0005] For example, for the production of electrodes with segmented coating (zebra coating), individual free-standing films can be produced and laminated in parallel alignment onto the target substrate, but this is associated with a very high time and equipment expenditure and a lot of waste (cuttings).

[0006] It is also known to use primer layers to produce electrodes with segmented coatings in order to create a targeted, local transfer of dry film to a substrate. For example, a dry layer is generated on a roller and transferred to a substrate only at those locations where the substrate is coated with an adhesion-promoting primer layer. Thus, the pattern of the primer layer applied to the substrate also determines the layout of the dry film layer on the substrate. This works well for some materials, but it is often observed that, depending on the cohesion or mechanical stability of the dry film layer generated on the roller, the transfer cannot be achieved with a clean edge.

[0007] Apart from that, it is known from US 2017 / 040591 A1 that, in order to produce electrodes with a segmented coating, a dry film is first produced which is carried on a first roller and forms a calendering nip with a second roller, the second roller carrying a removal film which is suitable for removing areas of the dry film from the first roller by exerting pressure in the calendering nip, so that a striped dry film (zebra pattern) is created on the first roller. The problem with this process is that the use of the removal film makes it cost-intensive because the removal film has to be renewed and that the removal film executes a certain meandering movement in the calendering nip, i.e. a certain movement in a direction parallel to the axis of rotation of the first and second rollers, as a result of which the two boundary lines of the respective dry film webs produced run wavy in the longitudinal direction of the dry film, at least in some regions.In other words, this process does not allow the two boundary lines of the dry film to run as strictly parallel lines along the longitudinal direction. Therefore, the resulting dry films exhibit edge accuracy that requires improvement.

[0008] WO 2020 / 148410 A2 discloses a multi-roll device for producing a dry film, in which the edge of the dry film is trimmed on the last roll of the multi-roll device at the end of the process. Edge trimming on the last roll of the multi-roll device has several disadvantages. Firstly, the dry film is already highly compacted at this point, which makes edge trimming more energy-intensive and leads to greater abrasion on the cutting tool. Secondly, the distance between the cutting device and the first calender nip of the multi-roll device is very great, which lengthens the transport path (e.g. of cut dry film material) from the cutting device to the first calender nip. Thirdly, there is a risk that improperly formed edges (poor parallelism or frayed areas) of the dry film will fold over during transport and thus lead to different layer thicknesses orCompaction of the layer before the unclean edges are trimmed.

[0009] A further difficulty with the dry film process is that large coating widths (i.e. widths of at least 300 mm perpendicular to the longitudinal direction of the dry film) mean that rolls used for post-calendering (post-compaction) have to be extremely large and robust in order to withstand the high line loads, which are correspondingly greater for wide coatings than for narrow coatings.

[0010] Based on this, it was the object of the present invention to provide a method for producing a dry film, a plant for producing a dry film, a dry film and a battery containing a dry film, which overcome at least one, preferably all, disadvantages of the prior art.

[0011] The object is achieved by the method having the features of claim 1, the system having the features of claim 10, the dry film having the features of claim 19 and the battery having the features of claim 29. The dependent claims show advantageous developments.

[0012] According to the invention, a method for producing a dry film is provided, comprising feeding a dry powder mixture and / or a dry mix into a first calender nip formed by a carrier roller and a first counter roller, wherein the carrier roller rotates about a carrier roller rotation axis at a first circumferential speed in a first rotational direction and the counter roller rotates about a counter roller rotation axis at a second circumferential speed, which is lower than the first circumferential speed, in a second rotational direction, wherein the second rotational direction is opposite to the first rotational direction, wherein the dry powder mixture and / or the dry mix passes through the calender nip in a conveying direction and a dry film is formed which is supported at least partially on the carrier roller, characterized in that at least one first processing device is used,which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a first outer segment of the carrier roller and at least one second processing device is used, which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a second outer segment of the carrier roller, wherein the carrier roller has an inner segment between the first outer segment and the second outer segment in a direction parallel to the carrier roller rotation axis, wherein the first and second processing devices are each suitable for removing regions of the dry film that are mounted on the outer segments of the carrier roller on the carrier roller (preferably at least by cutting, particularly preferably also by removal, e.g. by a removal unit).

[0013] The dry powder mixture can be in the form of a flowable powder. The dry mix can be in the form of a cohesive, non-flowable bulk material, in the form of flat agglomerates, or (already) in the form of a dry film (e.g., a dry film in ribbon form). In principle, it is conceivable that the dry powder mixture and the dry mix are not viewed as two different substances, but rather that a dry powder mixture is viewed as a special embodiment of a dry mix. In this case, the term "dry powder mixture and / or dry mix" can be simplified to the term "dry mix," with a dry powder mixture then being a special embodiment (species) of the dry mix (genus). The dry mix can then be in the form of a flowable powder (since it can be a dry powder mixture).

[0014] With the method according to the invention (dry film method), it is possible to provide segmented, strip-shaped dry films in a fast and energy-saving manner, which have very high edge accuracy. High edge accuracy is understood to mean that a web formed by the dry film (or all webs formed by the dry film) is / are defined in a longitudinal direction of the web by two boundary lines, wherein the boundary lines run essentially straight and essentially parallel to one another. By "essentially straight and essentially parallel to one another" is meant that a distance between the respective two boundary lines along the longitudinal direction varies by < 1000 pm, preferably < 500 pm, particularly preferably < 200 pm. According to the invention, a dry film is understood to mean, in particular, a non-self-supporting coating or layer (< 100 N / m 2tensile strength in the coating plane) or a free-standing, self-supporting film (> 100 N / m 2 Tensile strength in the coating plane), which results from a film formation process in which no solvents are used, ie in particular no solvents are used in the process according to the invention.

[0015] The method according to the invention is highly relevant for the layer production of battery electrodes (lithium-ion batteries, solid-state batteries, lithium-sulfur batteries, sodium-ion batteries), but is also relevant for other coatings, such as for energy storage devices (e.g. supercapacitors, fuel cells), electrochemical components (e.g. for electrolysis or catalyst layers), or adsorber layers formed from porous materials.

[0016] In a preferred embodiment of the method, the first and second processing devices are each suitable for removing the regions of the dry film that are mounted on the outer segments of the carrier roller, without any movement of their own, at least by cutting (preferably also by removal, e.g., by a removal unit of the system), whereby this particularly means that the first and second processing devices remain stationary during the method (i.e., do not move relative to the carrier roller). The same can also apply to other, preferably all, processing devices used in the method according to the invention. This embodiment can further increase the high edge accuracy, i.e., the strict straightness and parallelism of the two boundary lines of the dry film produced by the method.

[0017] In the process, the dry film can be transferred to the carrier roller without a substrate. This allows the process to produce a free-standing dry film, i.e. a dry film that is not supported on a substrate. In a step downstream of the process, the free-standing dry film can be applied to a substrate. The substrate can have a three-dimensional structure (e.g., a woven fabric, a nonwoven, or expanded metal). Furthermore, the substrate can have a texture (e.g., an etched, sandblasted, or lasered substrate). Apart from that, the substrate can have or consist of a porous layer (e.g., an electrode layer or a particle layer). The layer applied to the substrate can have been applied to the substrate using a slurry process or a dry film process.A primer layer may be present between the substrate and the dry film, which can support (i.e. strengthen) the bonding of the dry film to the substrate.

[0018] Alternatively, the dry film can already be laminated to a substrate during the process according to the invention. This allows the process to produce a dry film that is laminated to a substrate. In this case, too, the substrate can have a three-dimensional structure (e.g., a woven fabric, a nonwoven, or expanded metal). Furthermore, the substrate can be a textured substrate (e.g., an etched, sandblasted, or lasered substrate). Apart from that, the substrate can contain or consist of a porous layer (e.g., an electrode layer or a particle layer). The layer applied to the substrate can have been applied to the substrate using a slurry process or a dry film process. The substrate can have a primer layer before the dry film is laminated to assist the bonding of the dry film to the substrate.In this embodiment, however, it is also possible in principle to remove the dry film from the substrate (at the end of the process) to provide a free-standing dry film. Removing the substrate from the dry film may be useful (e.g., for the application of the dry film in a battery) if the substrate to which the dry film was laminated during the process according to the invention does not contain or consist of any electrically conductive material, e.g., is not suitable as a substrate for use in a battery.

[0019] The substrate may not contain or consist of any electrically conductive material, or it may contain or consist of an electrically conductive material, wherein the electrically conductive material is preferably selected from the group consisting of metal, carbon, and combinations thereof. The term "metal" also includes metal alloys.

[0020] The substrate can have a primer layer, at least in some areas, for strengthened bonding of the dry film. The primer layer can contain or consist of a polymer (or a binder, e.g., a thermoplastic material) and an electrically conductive material (e.g., carbon-containing materials such as carbon black, graphite, or similar). The primer layer preferably has a thickness in the range of <10 μm, particularly preferably in the range of <2 μm. The primer layer is preferably arranged in areas on the substrate that are opposite the inner segment of the carrier roller in a direction perpendicular to the carrier roller rotation axis. The primer layer has the advantage that strengthened adhesion of the dry film occurs at points on the substrate that are provided with the primer layer. By activating the polymer of the primer layer, e.g., heating (e.g.,When a thermoplastic polymer material is heated (e.g. by heated rollers or external heat sources such as infrared radiators), the primer layer softens. In this way, particles of the dry film are pressed into the primer layer, resulting in an increase in the contact area between the particles of the dry film and the primer layer. When the primer layer cools down (leaving the heating zone or switching off the heat source), the primer layer solidifies, and the increased contact area with the particles of the dry film pressed into the primer layer causes the dry film to bond to the substrate coated with the primer layer. Areas of the substrate that are not coated with a primer layer do not have an increased interface and therefore no increased bond to the dry film, which means that the dry film preferentially does not adhere in these areas.Consequently, the primer layer can further increase the edge accuracy of the produced dry film, which also allows intermittent coatings.

[0021] In a similar way to a primer layer, a roughened or three-dimensional substrate surface (e.g., nonwoven, wire mesh, expanded metal, and / or textured substrate, such as an etched substrate, sandblasted substrate, lasered substrate, or similar) can lead to locally enhanced adhesion and thus to an increase in edge accuracy. In this case, increased adhesion is present when the surface roughness Ra is >1 pm, preferably >5 pm, particularly preferably >10 pm, whereas the areas of the substrate with low adhesion to the dry film have roughnesses Ra of <1 pm.

[0022] The substrate may have or consist of a three-dimensional structure at least in some regions, wherein the substrate preferably contains or consists of a woven fabric, nonwoven fabric and / or expanded metal.

[0023] Furthermore, the substrate can have a texturing at least in some regions, wherein the texturing was preferably created by etching treatment, sandblasting treatment and / or laser treatment. The texturing is present in particular on a surface of the substrate facing the dry film. The texturing can lead to locally increased adhesion of the dry film and thus to an increase in edge accuracy. In addition, the substrate can have or consist of a porous layer at least in some regions, wherein the porous layer preferably contains or consists of an electrode layer and / or particle layer. The porous layer to which the dry film is applied can lead to locally increased adhesion of the dry film and thus to an increase in edge accuracy. The layer applied to the substrate can have been applied to the substrate using a slurry process or a dry film process.

[0024] Furthermore, it is possible to achieve improved adhesion of the dry film and thus increased edge accuracy by adding particulate adhesion aids to defined areas of the dry powder mixture and / or the dry mix.

[0025] The dry powder mixture and / or the dry mixture can contain an active material of an electrode of a battery. The dry powder mixture and / or the dry mixture can contain the active material in a mass fraction of >50 wt. %, preferably >70 wt. %, particularly preferably >90 wt. %, based on the total mass of the dry powder mixture and / or the dry mixture. The dry powder mixture can be in the form of a flowable powder. The dry mixture can be in the form of a cohesive, non-flowable bulk material, in the form of flat agglomerates, or (already) in the form of a dry film (e.g., a dry film in strip form). The active material is preferably selected from the group consisting of active material for a cathode of a battery and active material for an anode of a battery. The battery can preferably be a lithium or sodium battery.The active material for a cathode can be a material selected from the group consisting of lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NMC), nickel-rich lithium nickel manganese cobalt oxide (NMC 622, NMC 811 or related NMC materials), lithium nickel cobalt aluminum oxide (NCA), lithium cobalt oxide (LCO), lithium manganese nickel oxide (LMNO), high voltage spinel (HVS), carbon, sulfur, and combinations thereof. The active material for an anode can be a material selected from the group consisting of graphite, hard carbon, silicon, carbon, tin, silicon oxide, lithium, indium lithium titanate (LTO), and combinations thereof. In addition, they may be sodium-containing compounds based on metal oxides, polyanions (vanadates and / or phosphates) and analogues of Prussian Blue.

[0026] Furthermore, the dry powder mixture and / or the dry mix may contain an electrically conductive additive, wherein the electrically conductive additive is preferably selected from the group consisting of carbon nanotubes, carbon (e.g., carbon black, carbon nanotubes, and / or carbon fibers), graphite, graphene, porous carbons (e.g., activated carbon), and combinations thereof. The dry powder mixture and / or the dry mix may contain the electrically conductive additive in a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.%, particularly preferably 1-4 wt.%, based on the total mass of the dry powder mixture and / or the dry mix.

[0027] Furthermore, the dry powder mixture and / or the dry mix (as a binder or component of a binder) can contain a material which, in a non-fibrillatized state, exhibits a binder effect (i.e., is a "binder"), wherein the material is preferably selected from the group consisting of non-fibrillatable fluoropolymer (preferably polyvinylene difluoride PVDF, ethylene tetrafluoroethylene ETFE, and / or polytetrafluoroethylene PTFE), carboxymethylcellulose CMC, styrene butadiene rubber SBR, biopolymer, polyolefin (e.g., polyethylene, preferably polyethylene with a molecular weight of >1,000,000 g / mol), polypeptide (e.g., sericin), polyamide, polyacrylate, and mixtures thereof. In this case, the binder effect is not dependent on the formation of a fibril network (non-fibrillatable binder). The dry powder mixture and / or the dry mix can contain this material with a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.-%, particularly preferably 0.5-4 wt.%, based on the total mass of the dry powder mixture and / or the dry mix. In particular, the dry powder mixture and / or the dry mix (as a binder or component of a binder) can contain a fibrillatable material that is fibrillatable under the action of mechanical force, thermal influence and / or a physico-chemical influence and can also exert a binder effect (i.e. can also be a "binder"), wherein the material is preferably selected from the group consisting of polypeptide (e.g. sericin), plastic (e.g. fluoropolymer, such as PTFE, and / or polyolefin with a molecular weight of >1,000,000 g / mol, such as polyethylene with a molecular weight of >1,000,000 g / mol) and mixtures and combinations thereof (fibrillatable binder).Due to mechanical shear force in the calender gap, the material can form fibrils, which increase the mechanical stability of the dry film by forming a stabilizing network. The term "fibrils" refers in particular to thread-like structures that preferably have a diameter in the range of 0.001 pm to 1 pm and / or a length in the range of 1 pm to 100 pm. The dry powder mixture and / or the dry mixture can contain the fibrillatable material in a mass fraction of <10 wt.%, preferably <5 wt.%, particularly preferably <2 wt.%, very particularly preferably 0.3 to 2 wt.%, optionally 1 to 2 wt.%, based on the total mass of the dry powder mixture and / or the dry mixture.

[0028] Due to the storage of the produced dry film on the rollers, the binder can be present in the dry powder mixture and / or dry mix in a proportion of <10 wt.%, preferably <5 wt.%, particularly preferably <2 wt.%, most particularly preferably 0.3 to 2 wt.%, optionally 1 to 2 wt.%, based on the total weight of the dry powder mixture and / or dry mix. Optionally, the proportion of binder in the dry powder mixture and / or dry mix is ​​>0.1 wt.%, based on the total weight of the dry powder mixture and / or dry mix.

[0029] The activation of the binder effect (such as the formation of fibrils in PTFE or the point-to-point binder effect in PVDF or polyolefins) can occur thermally, mechanically, and / or chemically. The activation processes can be pre-formed in upstream process steps or generated in the calender gap. For upstream activation, grinding or mixing processes can be used in which shear forces act on the dry powder mixture and / or the dry mix, especially on the binder, through particle-to-particle collisions or collision with mechanical elements. Mills such as pin mills, jet mills, impact mills, ball mills, impact mills, mortar mills, roller mills, or mixers such as planetary mixers, Eirich mixers, kneaders, single-screw extruders, and / or twin-screw extruders can be used for this purpose.

[0030] The activation of the binders (e.g. fibrillation or softening or formation of physical or chemical bonds or a combination thereof) can also be achieved by thermal or chemical activation in addition to or instead of shear forces introduced into the dry powder mixture and / or the dry mix.

[0031] In the case of thermoplastic binders such as PVDF or polyolefins, activation can be achieved by heating near or above the softening temperature. If heating is used in addition to mechanical activation, heating well below the softening temperature may be sufficient. When activating fibrillar binders such as PTFE, transition temperatures must be taken into account. Fibrillar PTFE (e.g., emulsion-polymerized PTFE with high molecular weights, e.g., >10 6 g / mol, preferably >10 7g / mol) has a softening temperature above 300 °C. However, the fibril formation of such a PTFE can be thermally activated if it is subjected to mechanical stress above 18 °C. Thermal activation in conjunction with mechanical force can thus be achieved between 18 °C and 330 °C, preferably between 25 °C and 200 °C, particularly preferably between 60 °C and 180 °C, and very particularly preferably between 80 °C and 120 °C.

[0032] Conversely, processing below 18°C ​​allows mechanical processing (mixing, homogenizing, grinding, etc.) without causing fibrillation. Thus, at these low temperatures, the binder effect is not released, meaning the mixture is not prone to agglomeration and exhibits good flowability. After the binder has been activated, the dry powder mixture and / or the dry mix may tend to agglomerate and no longer flow freely or be free-flowing. This can be detrimental to further process control if the dry powder mixture and / or the dry mix must be free-flowing or free-flowing for dosing operations or conveying and feeding.When PTFE is activated in jet mills, for example, a fine dry powder mixture and / or a fine dry mix is ​​created, which must be processed directly, otherwise the active binder will lead to agglomeration and certain subsequent process steps can no longer be carried out.

[0033] The use of upstream processes for dry powder mixing and / or dry blend treatment also enables the recycling of dry film material that is generated as waste during film production. The waste material is returned to the dry powder mixing and / or dry blend, and the proportion of added waste material is controlled using a controlled dosing unit.

[0034] Since shear forces also arise in the film-forming calender nip between the carrier roll and the counter roll, mechanical activation of the binder can be achieved independently of or in addition to the dry powder mixture pretreatment and / or the dry mix pretreatment. Shear forces already result when the two rolls rotate at the same circumferential speed, so that film formation can be achieved. Preferably, a dry powder mixture and / or a dry mix is ​​used for this purpose in which the binder has already been activated in advance (e.g., fibrillation of the PTFE in upstream processes). In the case of fibrillated PTFE, fibrils may already be present in the dry powder mixture and / or the dry mix (and thus also distributed in all spatial directions in the resulting layer).By combining different activation types, both free-flowing, free-flowing dry powder mixtures and poorly flowing, agglomerated dry powder mixtures and / or dry mixes (e.g. ribbon-shaped dry films) can be used for film formation. Film formation is preferably achieved by using different peripheral rotational speeds of the carrier roller and counter roller, whereby increasing additional shear forces act on the dry powder mixture and / or the dry mix in the gap with increasing difference in peripheral rotational speed and binder activation is additionally supported. This can result in anisotropically aligned fibrils in the dry film. Preference is given to using peripheral rotational speeds with a ratio of the peripheral rotational speed of the carrier roller to the counter roller of >1:1, preferably greater than 2:1, particularly preferably >3:1, very particularly preferably >4:1.Preferably, peripheral rotational speeds with a ratio of the peripheral rotational speed of the carrier roller to the counter roller of <20:1 are used. Due to the shear forces introduced by rollers rotating at different speeds, a higher compaction of the dry film (= lower porosity) can be achieved at the same pressing forces than is achieved with pure pressing (same rotational speed of the rollers with a rotational peripheral speed ratio of 1:1). In the latter case, porosities of >60% result in the film formation step at the same pressing forces, so that strong post-compaction or higher pressing forces must be used during the film formation step, which can lead to particle damage. With the film formation according to the invention with different peripheral rotational speeds, however, it is directly possible to achieve porosities of <40% at the same pressing forces. The risk of particle damage is thus reduced.

[0035] The gap width used between the carrier roll and the counter roll can be between 5 pm and 1000 pm, preferably between 10 pm and 1000 pm, particularly preferably between 20 pm and 150 pm, particularly preferably between 30 pm and 100 pm, very preferably between 40 pm and 70 pm.

[0036] The process according to the invention makes it possible to use lower line loads during film formation compared to pure pressing. The line load used can be <500 kN / cm (e.g., a line load between 1 N / cm and 200 kN / cm), preferably <10 kN / cm (e.g., a line load between 10 N / cm and 10 kN / cm). Since deformation of the rolls can be avoided by low line loads, the carrier roll and / or counter roll (film-forming roll) can have a smaller roll diameter and / or a smaller roll width.

[0037] The diameter of the carrier roller and / or counter roller (film-forming roller) can be < 100 cm (e.g. between 10 cm and 100 cm), particularly preferably < 50 cm (e.g. between 10 cm and 50 cm), in particular < 30 cm. The roller diameters of the carrier rollers and counter roller(s) can be of different sizes. Smaller roller diameters have the advantage that lower layer thicknesses of the dry film can be achieved during film formation. Thus, with the method and the system according to the invention, layer thicknesses of the dry film between 5 μm and 1000 μm, preferably between 10 μm and 1000 μm, particularly preferably between 20 μm and 150 μm, particularly preferably between 30 μm and 100 μm, very preferably between 40 μm and 70 μm can be achieved.

[0038] The width (ie extension in a direction perpendicular to the roll axis) of the carrier roll and / or counter roll can be > 30 cm, preferably > 60 cm, particularly preferably > 100 cm (in particular up to 300 cm).

[0039] This effect can be further enhanced by using heated rollers (e.g., heated to a temperature between 18°C ​​and 330°C, preferably between 25°C and 200°C, particularly preferably between 60°C and 180°C, very particularly preferably between 80°C and 120°C). Thus, a dry powder mixture and / or a dry mix that has not been previously activated can be used for film formation. However, a dry powder mixture that is non-flowable or poorly flowable and / or a dry mix (e.g., a ribbon-shaped dry mix) can also be used.

[0040] When extruders such as twin-screw extruders are used to mix and / or pretreat the dry powder mixture and / or the dry blend and to activate the PTFE by applying shear force and thermal activation, free-flowing, agglomerated extrudates can be obtained. These can have particle sizes in the range from 50 μm to 5000 μm, preferably in the range from 200 μm to 2000 μm, particularly preferably in the range from 250 μm to 750 μm. In contrast to a fine dry powder mixture and / or a fine dry blend that has been pretreated in jet mills, the particles are significantly larger and have a significantly lower tendency toward further agglomeration. Thus, a storable dry powder mixture and / or a storable dry blend can be obtained, which can be conveyed into the calender nip for film formation without further treatment.By avoiding excessive activation of the binder (treatment at temperatures < 150 °C, preferably < 120 °C, with residence times in the shear force-inducing kneading zone of the extruder of < 60 s, preferably < 10 s), the extrudates can have a comparatively low hardness, which can allow good processing in the calender gap at relatively low pressing forces.

[0041] Furthermore, the dry powder mixture and / or the dry mixture may contain an ion-conducting substance, preferably an ion-conducting solid (solid electrolyte). The ion-conducting substance is preferably selected from the group consisting of ion-conducting solids (solid electrolytes), gel-like ion conductors, salt-like ion conductors, and mixtures thereof (preferably Li-ion-conducting and / or Na-ion-conducting). The ion-conducting solid is preferably selected from the group consisting of sulfidic solid ion conductors (e.g. lithium thiophosphates, LPS, argyrodite, LPSCI and / or LGPS, or a corresponding Na-ion-conducting sulfidic solid ion conductor), glassy solid ion conductors (e.g. LiAISiC or NaAISiC), polymeric solid ion conductors (e.g. PEO), ceramic solid ion conductors (e.g. LLZO or a corresponding Na-ion-conducting ceramic solid ion conductor) and mixtures thereof.The dry powder mixture and / or the dry mixture can contain the solid electrolyte with a mass fraction of 1-99 wt.%, preferably 5-30 wt.%, particularly preferably 10-20 wt.%, based on the total mass of the dry powder mixture.

[0042] The dry powder mixture and / or the dry mix can have a liquid content of <1 vol.%, based on the total volume of the dry powder mixture and / or the dry mix. In the method, the inner segment, the first outer segment, and the second outer segment of the carrier roller can each be defined by two mutually parallel boundary lines spanning the circumference of the carrier roller. In this case, at least one boundary line of the inner segment preferably lies on a boundary line of the first outer segment and / or second outer segment. In other words, the inner segment directly adjoins the first and / or second outer segment, i.e., contacts it.

[0043] The inner segment of the carrier roller can have, at least in some regions, a surface finish to which the dry film adheres (e.g. an adhesive coating on the surface of the carrier roller and / or a texturing of the surface of the carrier roller, e.g. a texturing produced by etching treatment, sandblasting treatment and / or laser treatment, optionally periodically or irregularly), wherein the first outer segment and / or second outer segment of the carrier roller has a surface finish to which the dry film does not adhere, wherein this surface finish is preferably configured as a smooth surface of the carrier roller. The smooth surface can have a mean roughness value Ra that is < 50% of the mean roughness value Ra that the carrier roller has in the inner segment. Particularly preferably, the smooth surface has a mean roughness value Ra in the range from 0.001 pm to 1 pm.The surface of the inner segment of the carrier roller can have a mean roughness Ra that is >50% of the mean roughness Ra of the smooth surface of the carrier roller, preferably a mean roughness between 0.1 pm and 10 pm. The advantage of this embodiment is that bonding of dry film to the carrier roller is reduced in areas where no dry film should bond to the carrier roller. In other words, the first and second processing devices only have to remove a smaller amount of dry film from the carrier roller, at least by cutting, i.e., unbonded dry film is available again earlier in the process to be able to be fed back into the first calender nip (as a dry powder mixture and / or as a dry mixture), which makes the process more efficient and can also shorten maintenance intervals for the processing device.

[0044] Furthermore, the inner segment of the carrier roller can have, at least in some regions, a surface finish to which the dry film adheres (e.g. an adhesive coating on the surface of the carrier roller and / or a texturing of the surface of the carrier roller, e.g. a texturing produced by etching treatment, sandblasting treatment and / or laser treatment, optionally periodically or irregularly), wherein a first outer segment of the counter roller, which is arranged in a direction perpendicular to the carrier roller rotation axis opposite the first outer segment of the carrier roller and / or a second outer segment of the counter roller, which is arranged in a direction perpendicular to the carrier roller rotation axis opposite the second outer segment of the carrier roller, has a surface finish to which the dry film does not adhere.The surface quality of the first outer segment of the counter roll and / or of the second outer segment of the counter roll is preferably designed as a recessed surface of the counter roll, wherein the recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roll has in a first region of an inner segment of the counter roll. The surface quality of the first outer segment of the counter roll and / or of the second outer segment of the counter roll, to which the dry film does not adhere, can further be designed as a coating (e.g. a coating containing or consisting of DLC and / or PTFE) of the first outer segment of the counter roll and / or of the second outer segment of the counter roll, which coating leads to lower adhesion (preferably an adhesion of at least 1 wt. % less dry film, particularly at least 10 wt.-% less dry film than in the inner segment of the carrier roller), preferably no adhesion, on the counter roller. Alternatively or additionally, the surface quality of the inner segment of the carrier roller, to which the dry film adheres, can be designed as a coating and / or texturing of the inner segment of the carrier roller, which leads to adhesion to the carrier roller. The coating can be an adhesive coating on the surface of the inner segment of the carrier roller. The texturing can have been created by etching treatment, sandblasting treatment and / or laser treatment (optionally periodic or irregular). The surface of the inner segment of the carrier roller can have a mean roughness Ra that is >50% of the mean roughness Ra of the surface of the first outer segment of the counter roller and / or the second outer segment of the counter roller, preferably have a mean roughness between 0.1 pm and 10 pm.The coating of the inner segment of the carrier roll and / or the first outer segment of the counter roll and / or the second outer segment of the counter roll can contain or consist of a material selected from the group consisting of PTFE, DLC, tungsten carbide, hard chromium, and combinations thereof. The advantage of this embodiment is that the bonding of dry film to the carrier roll is reduced in areas where no dry film should bond to the carrier roll. In other words, the first and second processing devices only have to remove a smaller amount of dry film from the carrier roll, at least by cutting, i.e., unbonded dry film is available again earlier in the process to be fed back into the first calender nip (as a dry powder mixture and / or as a dry mixture), which makes the process more efficient and can also shorten maintenance intervals for the processing device.

[0045] Optionally, the carrier roller has at least a second region of the inner segment which is designed like the first and / or second outer segment of the carrier roller, ie whose recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roller has in the first region of the inner segment.

[0046] The first and second processing devices can each have a cutting unit that is used to separate a region of the dry film that is mounted on the carrier roller at the respective outer segments of the carrier roller from a region of the dry film that is mounted on the carrier roller at the inner segment of the carrier roller by cutting (i.e., the cutting of the dry film takes place in a web direction in which the dry film is transported on the carrier roller). The advantage of separation by cutting compared to separation by exerting pressure by a moving removal film (as in the method of US 2017 / 040591 A1, for example) is that it can be ruled out with a high degree of certainty that the boundary lines of the dry film (i.e., the edges of the dry film) run in a wavy shape or fray at least in some regions in the longitudinal direction of the dry film.In other words, it can be ensured with a high degree of certainty that the edges of the dry film run straight and parallel to each other along its longitudinal direction. The edge accuracy of the produced dry film is thus increased.

[0047] The cutting unit is preferably selected from the group consisting of a roller blade, air nozzle, laser, and combinations thereof. Dry films with strong adhesion can also be cut using the roller blade and the laser. The roller blade can contain a material (e.g., brass as the material of the roller blade) that has a lower Vickers hardness (e.g., HV10) than a material on the surface of the carrier roll (e.g., chromium as the material of the surface of the carrier roll). This has the advantage that wear on the carrier roll can be reduced. The air nozzle is particularly suitable when an area of ​​the dry film is to be cut that lies on a roll segment that has a surface finish to which the dry film does not adhere (e.g.,first and / or second outer segment), because then the lower cutting force of the air nozzle can be sufficient to cut away residues of dry film that adhere to the carrier roller despite its non-adhesive surface. Further advantages of the air nozzle are that it requires little maintenance, the air speed can be easily adjusted for dry films of different thicknesses, and that the formation of the dry film or the structure of the dry film is not impaired because, unlike with a rotary knife, there is no accumulation of material in the area around the cutting edge (e.g. accumulation of dry film material on the blade of the rotary knife). The laser has the advantage that it enables contact-free cutting and is therefore gentler on the surface of the carrier roller than, for example, a rotary knife, which can allow the process to be carried out for longer and more economically.Furthermore, the laser can also prevent the accumulation of dry film material in the vicinity of the cutting edge, thus ensuring that the formation of the dry film or its structure is not impaired. The method allows for the switching on and off of the cutting unit of the respective processing device, as well as the effective force (e.g., the pressing force of the rotary cutter, the air flow intensity of the air nozzle, and / or the radiation intensity of the laser) to be controlled.

[0048] The cutting unit can have a positioning system. This can improve the edge accuracy and, for example, the positioning of the cutting unit on the substrate film. The positioning system can have a detector for detecting the positioning. Furthermore, the positioning system can have a displacement unit for positioning the cutting unit. In addition, the positioning system can have a control unit (separate from the system according to the invention) configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention can be configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. The regulation can be effected via feedback of information from a detector of the positioning system ("feedback" mechanism).

[0049] Furthermore, the first and second processing devices may each comprise a removal unit used to remove a portion of the dry film supported on the carrier roller at the respective outer segments of the carrier roller.

[0050] Furthermore, the first and second processing devices may each comprise a further removing unit used to remove a portion of the dry film that is perpendicular to the coating direction to realize intermittent coating in the coating direction.

[0051] The removal unit is preferably selected from the group consisting of an air nozzle, a scraper, a brush, a vacuum cleaner, and combinations thereof. The scraper and the brush have the advantage that they also enable the removal of dry films that adhere strongly to the carrier roller. The air nozzle or the vacuum cleaner is particularly suitable when an area of ​​the dry film is to be cut that lies on a roller segment with a surface finish to which the dry film does not adhere (e.g., the first and / or second outer segment). In this case, even the lower removal force of the air nozzle or the vacuum cleaner may be sufficient to cut dry film residues that adhere to the carrier roller despite its non-adherent surface finish.The extractor has the further advantage that the extracted dry film material (within a suction channel) can be easily transported back to the calender nip (return of dry film material), which avoids wasting dry film material and makes the process more economical. Since the processing device with the removal unit is arranged in a direction perpendicular to the carrier roller rotation axis opposite a first outer segment of the carrier roller, the transport path of removed dry film material to the calender nip of the carrier roller is also very short, which makes transport faster and more energy-efficient. In the process, the switching on and off and the effective force of the removal unit (e.g. an air flow intensity of the air nozzle, a pressing force of the brush and / or suction flow intensity of the extractor) of the respective processing device on the carrier roller can be controlled.

[0052] The removal unit and / or further removal unit can have a positioning system. This can improve the edge accuracy and, for example, the positioning of the removal unit on the substrate film. The positioning system can have a detector for detecting the positioning. Furthermore, the positioning system can have a displacement unit for positioning the removal unit. In addition, the positioning system can have a control unit (separate from the system according to the invention) that is configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention can be configured to control or regulate the positioning system, preferably a displacement unit of the positioning system.The regulation can be achieved by feedback of information from a detector of the positioning system (feedback mechanism).

[0053] The inner segment of the carrier roller can be divided into at least two inner segment regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer (e.g. 1, 2, 3, 4, 5 or 6), and an intermediate region is arranged between each two adjacent inner segment regions, the boundary of which is defined in the direction of the rotation axis of the carrier roller by two opposite boundary lines of the 2n boundary lines. In this case, the at least two inner segment regions can have a surface quality to which the dry film adheres, and the intermediate region can preferably each have a surface quality to which the dry film does not adhere. The advantage here is that a dry film having a striped pattern (zebra pattern) can also be produced in the inner segment of the carrier roller.

[0054] In a preferred embodiment, a further processing device can be used opposite each intermediate region of the inner segment in a direction perpendicular to the axis of rotation of the carrier roller, said further processing device being suitable for removing regions of the dry film that are mounted on the carrier roller in the intermediate region of the carrier roller, at least by cutting (i.e. the cutting of the dry film takes place in a web direction in which the dry film is transported on the carrier roller). The advantage of this is that a dry film having a striped pattern (zebra pattern) can also be produced in the inner segment of the carrier roller. By removing it by cutting, the dry film can have a high level of edge accuracy.

[0055] Each of the further processing devices can have a cutting unit that is used to separate, by cutting, a portion of the dry film that is supported on the carrier roller at the respective intermediate regions of the carrier roller from a portion of the dry film that is supported on the inner segment of the carrier roller. The cutting unit is preferably selected from the group consisting of a roller blade, air nozzle, laser, and combinations thereof. In the method, switching on, switching off, and an effective force of the cutting unit of the respective further processing device (e.g., a pressing force of the roller blade, an air flow intensity of the air nozzle, and / or a radiation intensity of the laser) can be controlled. The cutting unit can have a positioning system, optionally with at least one of the above-mentioned features.

[0056] In addition, each of the further processing devices can have a removal unit used to remove a portion of the dry film mounted on the carrier roller in the inner segment of the carrier roller, wherein the removal unit is preferably a roller. In the method, a roller is preferably used as the further processing device, the rotational axis of which is mounted parallel to the rotational axis of the carrier roller and the width of which corresponds to the width of the inner segment or an inner segment region. Upon contact of this roller with the carrier roller, the dry film is transferred across the entire width of the roller to the roller for further processing as a coating, and the outer segments remain on the carrier roller.The outer segments can then be removed from the outer segments of the carrier roller using a removal unit (preferably selected from the group consisting of an air nozzle, scraper, brush, vacuum cleaner, and combinations thereof). Several such rollers can also be arranged along the same rotation axis, for example, to remove at least two inner segment regions of the inner segment of the carrier roller from the carrier roller and transfer them to the rollers.

[0057] Furthermore, each further processing device can have a removal unit used to remove a portion of the dry film supported on the carrier roller at the respective intermediate regions of the carrier roller. The removal unit is preferably selected from the group consisting of an air nozzle, a scraper, a brush, a vacuum cleaner, and combinations thereof. In the method, the activation, deactivation, and the effective force of the removal unit (e.g., an air flow intensity of the air nozzle, a pressing force of the brush, and / or the suction flow intensity of the vacuum cleaner) of the respective processing device on the carrier roller can be controlled.

[0058] The removal unit, or optionally the additional removal unit, can be used to feed removed sections of the dry film to the first calender nip. The advantage of this is that dry film material is recycled, making the process more economical.

[0059] The removal unit and / or further removal unit can comprise a positioning system, optionally with at least one of the above-mentioned features. Removed areas of the dry film can, for example, be fed to a dry mix (dry blend), which is processed into a dry powder mixture, which is then fed to the first calender nip. Processing into a dry powder mixture preferably comprises a treatment selected from the group consisting of extruder treatment, jet mill, pin mill, impact mill, mortar mill, roller mill, and combinations thereof.

[0060] Alternatively, removed regions of the dry film can be fed to a dry powder mixture, which is then fed to the first calender nip. The proportion of the added, removed regions of the dry film can be at least 0.1 wt.%, preferably at least 1 wt.%, particularly preferably at least 10 wt.%, based on the total proportion of the dry powder mixture.

[0061] The dry powder mixture and / or the dry mix can be introduced into the calender gap by feeding and / or dosing devices (e.g. gravimetric dosing chute).

[0062] The first calender nip can have a width (i.e., an extension in a direction along the carrier roll rotation axis or a distance between the two end faces of the roll) of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm. Optionally, the first calender nip has a maximum width of 3000 mm. The wider the first calender nip, the more dry film can be produced per unit of time, which increases the throughput of the process according to the invention. These dimensions can also apply to additional calender nips.

[0063] Furthermore, the first calender nip can have a mask and / or a hopper arranged above the calender nip. The hopper or mask has the advantage that the dry powder mixture and / or the dry mix can be applied specifically to locations on the carrier roller where it is intended to form a dry film on the carrier roller. For example, a mask or hopper can reduce the application of a quantity of dry powder mixture and / or dry mix to at least the two opposite outer segments of the carrier roller, optionally also to intermediate segments of the carrier roller. The process can thus be carried out more efficiently because the areas to be coated are predefined and hardly any material binds to areas of the carrier roller that are not to be coated.

[0064] Laminating the dry film onto a substrate may comprise the following steps: i) conveying the dry film on the carrier roll into a second calendering nip formed by the carrier roll and a second counter roll, wherein the second counter roll rotates about a second counter roll rotation axis at a second peripheral speed that is higher than the first peripheral speed of the carrier roll, in a third rotational direction, wherein the third rotational direction is opposite to the first rotational direction; ii) optionally conveying the dry film together with the substrate further through at least one third, preferably further at least one fourth, particularly preferably further at least one fifth, in particular further at least one sixth, calendering nip;iii) Optionally conveying the dry film without substrate by transfer due to increased peripheral speeds through at least one third, preferably at least one fourth, particularly preferably at least one fifth, in particular at least one sixth, calender nip (a speed increase from roll to roll can be in the range of 1-1000%, preferably in the range of 5% to 100%, particularly preferably in the range of 10 to 50%).

[0065] The at least one third, at least one fourth, at least one fifth, and at least one sixth calender nips can each be formed by two rolls that rotate at different peripheral speeds in opposite directions of rotation. Furthermore, the different calender rolls can have different diameters. The rolls can be arranged linearly next to one another. Furthermore, the rolls can be arranged at an angle to one another. The advantage of this embodiment is that the dry film is further compacted. With the aid of the counter roll, and optionally at least one further roll, an additional shear force is exerted in the respective calender nips, inducing a transfer of the dry film, thereby achieving further compaction of the dry film.This avoids any downstream calendering or the need for high pressing forces and thus large roll diameters in the first and / or second calender nip. Film formation and subsequent densification or lamination can thus be spatially decoupled, both in terms of the components and in terms of the assemblies. This enables the use of less rigid or less massive assemblies, as well as the implementation of an angled structure instead of a linear structure, which carries the risk that a change in one calender nip opening could affect the opening of the adjacent nip.

[0066] The process may further comprise a step (preferably a step at the end of the process) in which the dry film is removed from a substrate to which the dry film was applied during the process. In this case, a free-standing dry film can also be obtained starting from a dry film initially laminated to a substrate (during the process).

[0067] According to the invention, a plant for producing a dry film is further provided, comprising a) a device configured to produce a dry film from a dry powder mixture and / or a dry mixture, wherein the device contains a carrier roller and a first counter roller, wherein the carrier roller and the counter roller form a first calender nip for feeding a dry powder mixture and / or a dry mixture, wherein the carrier roller is suitable for rotating about a carrier roller rotation axis and the counter roller is suitable for rotating about a counter roller rotation axis;b) a control unit which is at least configured to cause the carrier roller to rotate about its carrier roller rotation axis at a first circumferential speed in a first rotation direction and the counter roller to rotate about its counter roller rotation axis at a second circumferential speed which is lower than the first circumferential speed in a second rotation direction, wherein the second rotation direction is opposite to the first rotation direction, wherein the control unit is in particular configured to adjust a gap width and / or a contact pressure between the carrier roller and the first counter roller;characterized in that the system has at least one first processing device which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a first outer segment of the carrier roller and at least one second processing device which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a second outer segment of the carrier roller, wherein the carrier roller has an inner segment between the first outer segment and the second outer segment in a direction parallel to the carrier roller rotation axis, wherein the first and second processing devices are each suitable for removing regions of the dry film which are mounted on the outer segments of the carrier roller on the carrier roller, at least by cutting (preferably also by ablation, e.g. by a removal unit of the system);

[0068] With the system according to the invention, it is possible to provide segmented, strip-shaped dry films with very high edge accuracy in a fast and energy-saving manner.

[0069] The dry powder mixture can be in the form of a flowable powder. The dry mix can be in the form of a cohesive, non-flowable bulk material, in the form of flat agglomerates, or (already) in the form of a dry film (e.g., a dry film in ribbon form). In principle, it is conceivable that the dry powder mixture and the dry mix are not viewed as two different substances, but rather that a dry powder mixture is viewed as a special embodiment of a dry mix. In this case, the term "dry powder mixture and / or dry mix" can be simplified to the term "dry mix," with a dry powder mixture then being a special embodiment (species) of the dry mix (genus). The dry mix can then be in the form of a flowable powder (since it can be a dry powder mixture).The control unit can be configured to control individual peripheral rotational speeds of the individual rollers and / or a ratio of the peripheral rotational speeds of the rollers to one another.

[0070] Furthermore, the system may comprise a unit configured to control the individual roller spacings (i.e. the gap openings and / or the pressing forces resulting in the gap).

[0071] The control unit and / or unit can be configured to couple the control system with process monitoring devices so that the control system adjusts system parameters, such as rotational peripheral speeds, gap openings and / or pressing forces based on process monitoring values ​​(e.g. with regard to layer thickness, loading, homogeneity, defects and / or edge accuracy) in order to remain within the range of a specified coating result with a certain tolerance range.

[0072] In a preferred embodiment of the system, the first and second processing devices are each suitable for removing the regions of the dry film that are mounted on the outer segments of the carrier roller without any inherent movement, at least by cutting (preferably also by removal, e.g., by a removal unit of the system). This particularly means that the first and second processing devices remain stationary in the system (i.e., are not configured to move relative to the carrier roller). The same can also apply to further, preferably all, processing devices that the system according to the invention has.

[0073] If the system contains a dry powder mixture and / or a dry mix, the dry powder mixture and / or the dry mix may have at least one of the above-mentioned features.

[0074] In a preferred embodiment, the system contains a substrate and is configured to laminate the dry film onto the substrate, wherein the substrate preferably has a primer layer, at least in some regions, for reinforced bonding of the dry film. If the system contains a substrate, the substrate can have at least one of the above-mentioned features. The primer layer can contain or consist of a binder and an electrically conductive material.

[0075] The primer layer may have a thickness in the range of <10 µm, preferably <2 µm.

[0076] Furthermore, the primer layer can be arranged in areas on the substrate that are opposite the inner segment of the carrier roller, in a direction perpendicular to the carrier roller rotation axis.

[0077] The inner segment, the first outer segment, and the second outer segment of the carrier roller can each be defined by two mutually parallel boundary lines spanning the circumference of the carrier roller. Preferably, at least one boundary line of the inner segment lies on a boundary line of the first outer segment and / or second outer segment. In other words, the inner segment directly adjoins the first and / or second outer segment, i.e., contacts it.

[0078] The inner segment of the carrier roller can have, at least in some regions, a surface finish to which the dry film adheres (e.g. an adhesive coating on the surface of the carrier roller and / or a texturing of the surface of the carrier roller, e.g. a texturing produced by etching treatment, sandblasting treatment and / or laser treatment, optionally periodically or irregularly), wherein the first outer segment and / or second outer segment of the carrier roller has a surface finish to which the dry film does not adhere, wherein this surface finish is preferably configured as a smooth surface of the carrier roller. The smooth surface can have a mean roughness Ra that is < 50% of the mean roughness value that the carrier roller has in the inner segment. Particularly preferably, the smooth surface has a mean roughness Ra in the range from 0.005 pm to 1 pm.The surface of the inner segment of the carrier roller can have a mean roughness Ra that is >50% of the mean roughness Ra of the smooth surface of the carrier roller, preferably a mean roughness between 0.1 pm and 10 pm. Furthermore, the inner segment of the carrier roller can have, at least in some areas, a surface finish to which the dry film adheres (e.g., an adhesive coating on the surface of the carrier roller and / or a texturing of the surface of the carrier roller, e.g.,a texturing produced by etching treatment, sandblasting treatment and / or laser treatment, optionally periodically or irregularly), wherein a first outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the first outer segment of the carrier roll and / or a second outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the second outer segment of the carrier roll, has a surface finish to which the dry film does not adhere.The surface quality of the first outer segment of the counter roll and / or of the second outer segment of the counter roll is preferably designed as a recessed surface of the counter roll, wherein the recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roll has in a first region of an inner segment of the counter roll. The surface quality of the first outer segment of the counter roll and / or of the second outer segment of the counter roll can alternatively or additionally be designed as a coating (e.g. a coating containing or consisting of DLC and / or PTFE) of the first outer segment of the counter roll and / or of the second outer segment of the counter roll, which coating leads to lower adhesion (preferably an adhesion of at least 1 wt. % less dry film, particularly at least 10 wt.-% less dry film than in the inner segment of the carrier roller), preferably no adhesion, on the counter roller, wherein the inner segment of the carrier roller optionally has a coating to which the dry film adheres. The coating can be an adhesive coating on the surface of the inner segment of the carrier roller. The coating can further be a textured coating of the inner segment of the carrier roller (e.g. a textured coating produced by laser structuring and / or sandblasting, optionally periodically or irregularly). The surface of the inner segment of the carrier roller can have a mean roughness Ra that is >50% of the mean roughness Ra of the surface of the first outer segment of the counter roller and / or the second outer segment of the counter roller, preferably have a mean roughness between 0.1 pm and 10 pm.The coating particularly preferably contains or consists of a material selected from the group consisting of PTFE, DLC, tungsten carbide, hard chrome and combinations thereof.

[0079] Optionally, the carrier roller has at least a second region of the inner segment which is designed like the first and / or second outer segment of the carrier roller, ie whose recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roller has in the first region of the inner segment.

[0080] The first and second processing devices can each have a cutting unit configured to separate a portion of the dry film supported on the respective outer segments of the carrier roller from a portion of the dry film supported on the inner segment of the carrier roller by cutting (i.e., the cutting of the dry film occurs in a web direction in which the dry film is transported on the carrier roller). The cutting unit is preferably selected from the group consisting of a rotary blade, an air nozzle, a laser, and combinations thereof. The control unit of the system can further be configured to control switching on, switching off, and an effective force of the cutting unit of the respective processing device (e.g., a pressing force of the rotary blade, an air flow intensity of the air nozzle, and / or a radiation intensity of the laser).

[0081] The cutting unit can have a positioning system. This can improve the edge accuracy and, for example, the positioning of the cutting unit on the substrate film. The positioning system can have a detector for detecting the positioning. Furthermore, the positioning system can have a displacement unit for positioning the cutting unit. In addition, the positioning system can have a control unit (separate from the system according to the invention) configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention can be configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. The regulation can be achieved via feedback of information from a detector of the positioning system ("feedback" mechanism).

[0082] Furthermore, the first and second processing devices can comprise a removal unit configured to remove a portion of the dry film supported on the respective outer segments of the carrier roller. The removal unit is preferably selected from the group consisting of an air nozzle, a scraper, a brush, a vacuum cleaner, and combinations thereof. The control unit of the system can further be configured to control the activation, deactivation, and the effective force of the removal unit (e.g., an air flow intensity of the air nozzle, a pressing force of the brush, and / or the suction flow intensity of the vacuum cleaner) of the respective processing device on the carrier roller.

[0083] Furthermore, the first and second processing devices may comprise a further removing unit configured to remove a portion of the dry film perpendicular to the coating direction to realize intermittent coating in the coating direction.

[0084] The removal unit and / or further removal unit can have a positioning system. This can improve the edge accuracy and, for example, the positioning of the removal unit on the substrate film. The positioning system can have a detector for detecting the positioning. Furthermore, the positioning system can have a displacement unit for positioning the removal unit. In addition, the positioning system can have a control unit (separate from the system according to the invention) that is configured to control or regulate the positioning system, preferably a displacement unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention can be configured to control or regulate the positioning system, preferably a displacement unit of the positioning system.The regulation can be effected via feedback of information from a detector of the positioning system (feedback mechanism). The inner segment of the carrier roller can be divided into at least two inner segment regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and an intermediate region is arranged between each two adjacent inner segment regions, the boundary of which is defined in the direction of the rotational axis of the carrier roller by two opposite boundary lines of the 2n boundary lines.

[0085] In this case, the at least two inner segment regions can have a surface quality to which the dry film adheres and the intermediate region can preferably each have a surface quality to which the dry film does not adhere.

[0086] Furthermore, the system can have, in a direction perpendicular to the carrier roller rotation axis, opposite each intermediate region of the inner segment, a further processing device which is each suitable for removing regions of the dry film which are mounted on the carrier roller in the intermediate region of the carrier roller, at least by cutting.

[0087] Each of the further processing devices can have a cutting unit configured to separate a portion of the dry film supported on the carrier roller at the respective intermediate regions of the carrier roller from a portion of the dry film supported on the carrier roller at the inner segment of the carrier roller by cutting (i.e., the cutting of the dry film occurs in a web direction in which the dry film is transported on the carrier roller). The cutting unit is preferably selected from the group consisting of a rotary blade, an air nozzle, a laser, and combinations thereof. The control unit of the system can further be configured to control the switching on, switching off, and the effective force of the cutting unit (e.g., a pressing force of the rotary blade, an air flow intensity of the air nozzle, and / or a radiation intensity of the laser) of the respective further processing devices on the carrier roller.The cutting unit can have a positioning system, optionally with at least one of the above-mentioned features. In addition, each of the further processing devices can have a removal unit configured to remove a region of the dry film mounted on the carrier roller in the inner segment of the carrier roller, wherein the removal unit is preferably a roller. In the system, a roller is preferably used as a further processing device, the rotational axis of which is mounted parallel to the rotational axis of the carrier roller and the width of which corresponds to the width of the inner segment or an inner segment region. Upon contact of this roller with the carrier roller, the dry film is transferred across the entire width of the roller to the roller for further processing or coating, and the outer segments remain on the carrier roller.The outer segments can then be removed from the outer segments of the carrier roller using a removal unit (preferably selected from the group consisting of an air nozzle, scraper, brush, vacuum cleaner, and combinations thereof). Several such rollers can also be arranged along the same rotation axis, for example, to remove at least two inner segment regions of the inner segment of the carrier roller from the carrier roller and transfer them to the rollers.

[0088] Furthermore, each of the further processing devices can have a removal unit configured to remove a portion of the dry film supported on the carrier roller at the respective intermediate regions of the carrier roller. The removal unit is preferably selected from the group consisting of air nozzle, scraper, brush, vacuum cleaner, and combinations thereof. The control unit of the system can further be configured to control the activation, deactivation, and effective force of the removal unit of the respective further processing devices (e.g., an air flow intensity of the air nozzle, a pressing force of the brush, and / or suction flow intensity of the vacuum cleaner) on the carrier roller.

[0089] The removal unit, optionally also the additional removal unit, can be configured to feed removed areas of the dry film to the first calender nip. Preferably, the control unit of the system is configured to control the feeding of removed areas of the dry film to the first calender nip. The removal unit and / or additional removal unit can have a positioning system, optionally with at least one of the above-mentioned features.

[0090] Optionally, the removal unit, and preferably also the further removal unit, can be configured to first feed removed areas of the dry film to a dry mixture (dry mix), wherein a processing device of the system is configured to process the dry mixture (dry mix) into a dry powder mixture and feed it to the first calender nip. The processing device is preferably selected from the group consisting of an extruder, jet mill, pin mill, impact mill, mortar mill, roller mill, and combinations thereof.

[0091] Alternatively, the removal unit, preferably also the further removal unit, can be configured to first feed removed regions of the dry film to a dry powder mixture, wherein the system is configured to feed the dry powder mixture to the first calender nip, wherein the proportion of the fed, removed regions of the dry film is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, most preferably at least 10 wt.%, based on the total proportion of the dry powder mixture.

[0092] The system may comprise a feeding and / or dosing device (e.g. a gravimetric dosing chute) suitable for introducing the dry powder mixture and / or the dry mix into the calender gap.

[0093] The first calender nip can have a width of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm. Optionally, the first calender nip has a maximum width of 3000 mm. The wider the first calender nip, the more dry film can be produced per unit of time, which increases the throughput of the system according to the invention. These dimensions can also apply to further calender nips of the system. The gap width between the carrier roll and the counter roll can be between 5 pm and 1000 pm, preferably between 10 pm and 1000 pm, particularly preferably between 20 pm and 150 pm, particularly preferably between 30 pm and 100 pm, very preferably between 40 pm and 70 pm.

[0094] Furthermore, the system according to the invention makes it possible to use lower line loads during film formation compared to pure pressing. The control unit of the system can be configured to apply a line load of <500 kN / cm (e.g., to apply a line load between 1 N / cm and 200 kN / cm), preferably <10 kN / cm (e.g., to apply a line load between 10 N / cm and 10 kN / cm). Since deformation of the rolls can be avoided by low line loads, the carrier roll and / or counter roll (film-forming roll) can have a smaller roll diameter and / or a smaller roll width.

[0095] The diameter of the carrier roller and / or counter roller (film-forming roller) can be < 100 cm (e.g. between 10 cm and 100 cm), particularly preferably < 50 cm (e.g. between 10 cm and 50 cm), in particular < 30 cm. The roller diameters of the carrier rollers and counter roller(s) can be of different sizes. Smaller roller diameters have the advantage that thinner dry film thicknesses can be achieved during film formation. Thus, with the method and the system according to the invention, dry film thicknesses of between 5 pm and 1000 pm, preferably between 10 pm and 1000 pm, particularly preferably between 20 pm and 150 pm, particularly preferably between 30 pm and 100 pm, very preferably between 40 pm and 70 pm can be achieved.

[0096] The width (ie extension in a direction perpendicular to the roll axis) of the carrier roll and / or counter roll can be > 30 cm, preferably > 60 cm, particularly preferably > 100 cm (in particular up to 300 cm).

[0097] The system can be configured to heat the rollers (e.g., by a heating element of the system). The control unit of the system can be configured to heat the rollers to a temperature between 18°C ​​and 330°C, preferably between 25°C and 200°C, more preferably between 60°C and 180°C, and very preferably between 80°C and 120°C. Thus, a dry powder mixture and / or a dry mix that has not been previously activated can also be used for film formation. However, a dry powder mixture that is non-flowable or poorly flowable and / or a dry mix (e.g., a ribbon-shaped dry mix) can also be used.

[0098] Furthermore, the first calender nip can have a mask and / or a hopper arranged above the calender nip. The mask is preferably suitable for reducing the application of a quantity of dry powder mixture and / or dry mixture to at least the two opposite outer segments of the carrier roll, optionally also to at least one intermediate region of the inner segment of the carrier roll.

[0099] The system may include a second counter roll forming a second calender nip with the carrier roll, the system being configured to convey the dry film on the carrier roll into the second calender nip, the control unit being configured to cause the second counter roll to rotate in a third rotational direction about a second counter roll rotation axis at a second peripheral speed that is higher than the first peripheral speed of the carrier roll, the third rotational direction being opposite to the first rotational direction.

[0100] The system may further comprise at least one third, preferably at least one fourth, particularly preferably at least one fifth, very particularly preferably at least one sixth, in particular at least one seventh, roller.

[0101] Furthermore, the system can be configured to convey the dry film together with a substrate through at least one third, preferably further at least one fourth, particularly preferably further at least one fifth, in particular further at least one sixth, calender nip, each formed by two rollers. The at least one third, at least one fourth, at least one fifth, and at least one sixth calender nip can each be formed by two of these rollers, which rotate at different peripheral speeds in opposite directions of rotation. Optionally, the two rollers are arranged linearly or at an angle to one another. An angled arrangement has the advantage that the assemblies for film formation and lamination are decoupled.Furthermore, the radii of the two rolls can be different, which has the advantage that a higher pressing force can be exerted on the calender nip (due to the roll with the larger radius). In particular, the control unit of the system is configured to adjust the gap width of the calender nips between the two rolls and / or to adjust the contact pressure in the calender nips between the two rolls.

[0102] Furthermore, the system can be configured to convey the dry film with or without the substrate through at least one third, preferably at least one fourth, particularly preferably at least one fifth, in particular at least one sixth, calender nip, each formed by two rollers. The at least one third, at least one fourth, at least one fifth, and at least one sixth calender nip can each be formed by two of these rollers, which rotate at different circumferential speeds in opposite directions of rotation. The dry film can be transferred to a substrate in the third, fourth, fifth, or sixth nip.

[0103] In addition, the system can be configured to convey the dry film without substrate by transfer due to increased peripheral speeds through at least one third, preferably at least one fourth, particularly preferably at least one fifth, in particular at least one sixth, calender gap.

[0104] Furthermore, the roller arrangement can be configured such that two dry films are produced simultaneously in two first calender nips. Both dry films can be transferred to a third, fourth, fifth, or sixth calender nip and / or transferred there to a substrate. This allows for simultaneous double-sided coating or a multi-layer coating.

[0105] The system can also be configured to remove the dry film from a substrate to which the dry film has been applied by the system. The system's control unit can be configured to initiate the removal of the dry film from the substrate. In this case, the system can also produce a freestanding dry film from a dry film laminated to a substrate.

[0106] In a preferred embodiment, the system is configured to carry out the method according to the invention. Thus, the system can have at least one feature or at least one configuration necessary for carrying out the method according to the invention.

[0107] According to the invention, a dry film is further provided which is arranged as at least one web, preferably a plurality of parallel webs, on a substrate, wherein the at least one web, preferably each of the plurality of parallel webs, is defined in a longitudinal direction of the web(s) by two boundary lines, characterized in that the boundary lines run substantially straight and substantially parallel to one another. "Substantially straight and substantially parallel to one another" is understood to mean that a distance between the respective two boundary lines along the longitudinal direction varies by <1000 pm, preferably <500 pm, particularly preferably <200 pm.

[0108] The at least one web, preferably each of the plurality of parallel webs, can have a length of at least 0.05 m, preferably at least 0.5 m, particularly preferably at least 1 m, most preferably at least 5 m, in particular at least 10 m, in the longitudinal direction of the web(s).

[0109] Furthermore, the at least one web, preferably each of the plurality of parallel webs, can have a width of at least 200 mm and / or a maximum of 6000 mm perpendicular to the longitudinal direction of the web(s), preferably a width in the range of 250 mm to 1300 mm, particularly preferably a width in the range of 550 to 1250 mm. In particular embodiments, the at least one web, preferably each of the plurality of parallel webs, can have a width of at least 1 mm and a maximum of 50 mm perpendicular to the longitudinal direction of the web(s).

[0110] In a preferred embodiment, the dry film is arranged on the substrate as at least two parallel tracks, preferably as at least three parallel tracks, particularly preferably as at least four parallel tracks, in particular as at least five parallel tracks.

[0111] The substrate on which the dry film is arranged may have or consist of a three-dimensional structure, which preferably contains or consists of a woven fabric, nonwoven fabric and / or expanded metal.

[0112] Furthermore, the substrate may have a texturing which has preferably been produced by etching treatment, sandblasting treatment and / or laser treatment, wherein the texturing is present in particular on a surface of the substrate which faces the dry film.

[0113] Furthermore, the substrate may comprise or consist of a porous layer, wherein the porous layer preferably comprises or consists of an electrode layer and / or particle layer. The layer applied to the substrate may have been applied to the substrate using a slurry process or a dry film process.

[0114] The substrate on which the dry film is arranged preferably contains or consists of an electrically conductive material, wherein the electrically conductive material is preferably selected from the group consisting of metal, carbon, and combinations thereof. The term "metal" also includes metal alloys.

[0115] A primer layer can be arranged at least in regions between the dry film and the substrate, contacting both the dry film and the substrate. The primer layer can contain or consist of a polymer (or a binder) and an electrically conductive material. The primer layer preferably has a thickness in the range of <10 pm, particularly preferably in the range of <2 pm. The primer layer is preferably arranged in regions on the substrate that lie opposite the inner segment of the carrier roller, in a direction perpendicular to the carrier roller rotation axis. The primer layer has the advantage that increased adhesion of the dry film occurs at points on the substrate that are provided with the primer layer. Consequently, the primer layer can further increase the edge accuracy of the produced dry film.

[0116] The dry film can contain or consist of an active material of an electrode of a battery. The dry film can contain the active material in a mass fraction of >50 wt.%, preferably >70 wt.%, particularly preferably >90 wt.%, based on the total mass of the dry film. The active material is preferably selected from the group consisting of active material for a cathode of a battery and active material for an anode of a battery. The battery can preferably be a lithium-ion or sodium-ion battery.The active material for a dry-film cathode can be a material selected from the group consisting of lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NMC), nickel-rich lithium nickel manganese cobalt oxide (NMC 622, NMC 811, or related NMC materials), lithium nickel cobalt aluminum oxide (NCA), lithium cobalt oxide (LCO), lithium manganese nickel oxide (LMNO), high-voltage spinel (HVS), carbon, sulfur, and combinations thereof. The active material for a dry-film anode can be a material selected from the group consisting of graphite, hard carbon, silicon, carbon, tin, silicon oxide, lithium, indium lithium titanate (LTO), and combinations thereof.In addition, the dry film may contain sodium-containing compounds based on metal oxides, polyanions (vanadates and / or phosphates) and analogues of Prussian Blue.

[0117] Furthermore, the dry film may contain an electrically conductive additive, wherein the electrically conductive additive is preferably selected from the group consisting of carbon nanotubes, carbon particles (e.g., carbon black, carbon nanofibers, and / or carbon fibers), graphite, graphene, porous carbons (e.g., activated carbon), and combinations thereof. The dry film may contain the electrically conductive additive in a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.%, particularly preferably 1-4 wt.%, based on the total mass of the dry film.Furthermore, the dry film can contain (as a binder or component of a binder) a non-fibrilized material which exerts a binder effect, wherein the material is preferably selected from the group consisting of fluoropolymer (preferably polyvinylene difluoride PVDF, ethylene tetrafluoroethylene ETFE, polytetrafluoroethylene PTFE), carboxymethylcellulose CMC, styrene butadiene rubber SBR, biopolymer, polyolefin (e.g. polyethylene, preferably polyethylene with a molecular weight of >1,000,000 g / mol), polypeptide (e.g. sericin), polyamide, polyacrylate and mixtures thereof. The dry film can contain this material in a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.%, particularly preferably 0.5-1 wt.%, based on the total mass of the dry film.

[0118] In particular, the dry film (as a binder or component of a binder) can contain a fibrillated material (or fibrils) which exerts a binding effect, wherein the material is preferably selected from the group consisting of fibrillated polypeptide (e.g. sericin), fibrillated plastic (e.g. fluoropolymer, such as PTFE, and / or polyolefin with a molecular weight of >1,000,000 g / mol, such as polyethylene with a molecular weight of >1,000,000 g / mol) and mixtures and combinations thereof. For example, the dry film can contain fibrillatable PTFE with a molecular weight of >10 6 g / mol, preferably >10 7g / mol. The fibrillated material increases the mechanical stability of the dry film because it forms a stabilizing network of fibrils. The dry film can have anisotropically aligned fibrils. The term "fibrillated material" or "fibrils" refers in particular to thread-like structures that preferably have a diameter in the range of 0.001 pm to 1 pm and / or a length in the range of 1 pm to 100 pm. The fibrillated material or fibrils can be isotropically distributed in the dry film. The dry film can contain the fibrillated material or fibrils in a mass fraction of < 10 wt. %, preferably < 5 wt. %, particularly preferably < 2 wt. %, very particularly preferably 0.3 to 2 wt. %, optionally 1 to 2 wt. %, based on the total mass of the dry film. The fibrillated material or fibrils can be anisotropically distributed in the dry film.

[0119] Furthermore, the dry film can contain an ion-conducting substance, preferably an ion-conducting solid (solid electrolyte). The ion-conducting substance is preferably selected from the group consisting of ion-conducting solids, gel-like ion conductors, salt-like ion conductors, and mixtures thereof. The ion-conducting solid is particularly preferably selected from the group consisting of sulfidic solid ion conductors (e.g., lithium thiophosphates, LPS, argyrodite, LPSCI and / or LGPS, or sodium analogues), glassy solid ion conductors (e.g., LiAISiC or NaAISiC), polymeric solid ion conductors (e.g., PEO), ceramic solid ion conductors (e.g., LLZO, Lisocon and / or Nasicon, or a corresponding Na-ion-conducting ceramic solid ion conductor), and mixtures thereof. The dry film may contain the solid electrolyte in a mass fraction of 1-99 wt.%, preferably 5-30 wt.%, particularly preferably 10-20 wt.%, based on the total mass of the dry film.

[0120] The dry film may have a thickness (ie in a direction perpendicular to the largest area of ​​the dry film) in the range of 5 pm to 500 pm, preferably in the range of 10 pm to 150 pm, particularly preferably in the range of 30 pm and 100 pm, very preferably in the range of 40 pm and 70 pm.

[0121] The dry film may have a liquid content of <1 vol.%, relative to the total volume of the dry film.

[0122] The dry film obtained by the process according to the invention can have a porosity of 15-80%, preferably 20-50%, particularly preferably 25-35%. Through subsequent compaction, the dry film can have a porosity of 0.1-25%, preferably 0.1-10%, particularly preferably 0.1-5%.

[0123] As a result of the process according to the invention, the dry film can have a wave-shaped pattern which extends in the longitudinal direction of the web(s) of the dry film and extends perpendicular to the longitudinal direction of the web(s) (i.e. in the transverse direction) between the essentially straight and essentially mutually parallel boundary lines of the (respective) web(s) of the dry film, wherein waves of the wave-shaped pattern preferably have a periodic spacing in the transverse direction of the (respective) web(s) in the range of > 0 mm and <10 mm, preferably in the range of > 0 mm and <5 mm. This wave-shaped pattern can result from different peripheral rotational speeds. The periodic spacing of the wave patterns can depend on the absolute peripheral rotational speeds of the carrier rolls and counter roll, as well as on the gap used. The relationship arises in combination with the rheological properties of the dry mixture used.At higher differences in peripheral rotation speeds, the pattern may be more pronounced and have larger distances between the individual stripes than is the case with lower differences in peripheral rotation speeds.

[0124] The dry film can be produced using a method according to the invention. The dry film can thus have at least one feature that necessarily results from carrying out the method according to the invention. According to the invention, a battery is further provided, comprising a) an electrode that contains or consists of a dry film according to the invention; b) a counterelectrode; and c) an electrolyte, preferably a liquid electrolyte or a solid electrolyte, arranged between the electrode and the counterelectrode.

[0125] The subject matter of the invention will be explained in more detail with reference to the following figures, without wishing to restrict it to the specific embodiments shown here.

[0126] Figure 1 shows an embodiment of a method according to the invention and a system according to the invention for producing a dry film. The upper view is in the direction of view of the carrier roller 3 and the counter-roller 4 along the carrier roller rotation axis TR, and the lower view is in the direction perpendicular to the carrier roller rotation axis TR, toward the side on which the processing devices 7, 8, 15, and 16 are arranged.A dry powder mixture is fed into a first calender nip 2 formed by a carrier roller 3 and a first counter roller 4, wherein the carrier roller 3 rotates about a carrier roller rotation axis TR at a first peripheral speed in a first rotation direction 5 and the counter roller 4 rotates about a counter roller rotation axis GR at a second peripheral speed that is lower than the first peripheral speed in a second rotation direction 6, wherein the second rotation direction 6 is opposite to the first rotation direction 5. The dry powder mixture passes through the first calender nip 2 in a conveying direction, forming a dry film that is supported at least partially on the carrier roller 3.At least one first processing device 7 is used, which is arranged in a direction perpendicular to the carrier roller rotation axis TR opposite a first outer segment 9 of the carrier roller 3, and at least one second processing device 8 is used, which is arranged in a direction perpendicular to the carrier roller rotation axis TR opposite a second outer segment 10 of the carrier roller 3. The carrier roller 3 has, in a direction parallel to the carrier roller rotation axis TR, an inner segment 11 between the first outer segment 9 and the second outer segment 10. The first processing device 7 and the second processing device 8 are each suitable for removing regions of the dry film that are mounted on the outer segments 9, 10 of the carrier roller 3, at least by cutting.To laminate the dry film to a substrate, the dry film is passed through a second calender nip 17, which is formed by a third roller and the carrier roller 3. Since the embodiment shown in Figure 1 involves a symmetrical arrangement of a first and second pair of carrier rollers 3 and counter-roller 4, the third roller of the first pair is formed here by the carrier roller of the second pair, and the third roller of the second pair is formed by the carrier roller of the first pair. In the second calender nip 17, the dry film can be laminated / transferred to a substrate (not shown), which is passed through the second calender nip 17 together with the dry film. Due to the symmetrical arrangement of the two pairs of carrier rollers 3 and counter-roller 4, the substrate can be laminated with dry film on both sides (double-sided lamination).In the illustrated embodiment, the carrier roller 3 further comprises two further processing devices 15, 16, each arranged opposite an intermediate region 14 of the inner segment 11 in a direction perpendicular to the carrier roller rotation axis TR. These two processing devices make it possible to divide the dry film into two separate dry film belts or dry film strips.

[0127] Figure 2 shows a further embodiment of a method according to the invention or of a system according to the invention for producing a dry film, which is essentially identical to the embodiment shown in Figure 1. The upper illustration is in the direction of view of the carrier roller 3 and the counter-roller 4 along the carrier roller rotation axis, the middle illustration is in the direction of view perpendicular to the carrier roller rotation axis TR on the side on which the processing devices 7, 8, 15 and 16 are arranged and the lower illustration is in the direction of view perpendicular to the carrier roller rotation axis TR on the side on which the dry powder mixture 1 is fed into the first calender nip 2.The difference from the embodiment of Figure 1 is that the second calender nip 17 is not formed by the carrier roller 3 of the first roller pair and the carrier roller 3 of the second roller pair, but by the respective carrier roller 3 and a third roller 19 or second counter-roller, which rotates about its second counter-roller rotation axis 2GR in a third rotation direction 20 opposite to the first rotation direction 5. Due to the symmetrical arrangement, the respective third rollers 19 form a third calender nip 18, in which the dry film can be laminated to a substrate (not shown). The advantage of using the two third rollers 19 is that the dry film undergoes additional compaction and pressing in the second calender nip 17 before it is laminated to the substrate in the third calender nip 18, which can make the dry film mechanically more stable.

[0128] Figure 3 shows a further embodiment of a method according to the invention and of a system according to the invention for producing a dry film, which is essentially identical to the embodiment shown in Figure 1. The upper illustration is in the direction of view of the carrier roller 3 and the counter-roller 4 along the carrier roller rotation axis and the lower illustration is in the direction of view perpendicular to the carrier roller rotation axis TR onto the side on which the processing devices 7, 8 are arranged. One difference from the embodiment of Figures 1 and 2 is that the additional processing devices 15, 16 are missing, so that it is not possible to divide the dry film into two separate dry film belts or dry film strips, i.e. only a single dry film belt or a single dry film strip is produced.A further difference is that the carrier roller 3 has a first surface finish 12 in an inner segment of the carrier roller 3, which causes the dry film to adhere to the carrier roller 3, and the carrier roller 3 has a second surface finish 13 in the first and second outer segments of the carrier roller, which causes the dry film to not adhere. The second surface finish is designed here as a smooth surface of the carrier roller, wherein the smooth surface has a mean roughness Ra that is < 50% of the mean roughness that the carrier roller has in the inner segment. This embodiment has the advantage of preventing dry film from adhering to segments of the carrier roller 3 to which no dry film should bond.A dry film that does not bond to these segments of the carrier roller 3 can be fed back into the first calender nip 2 (as a dry powder mixture), which makes the process more efficient and can also shorten maintenance intervals for the processing devices 7, 8.

[0129] Figure 4 shows a carrier roller 3 from the embodiment of Figure 3 together with parts of the processing devices in a direction perpendicular to the carrier roller rotation axis TR. The carrier roller 3 has a second surface finish 13 in each of the first outer segment and the second outer segment, which ensures that the dry film 3 does not adhere to it. This has the advantage that the cutting unit 23 (here: an air nozzle) can cut the dry film more easily and with less energy expenditure (i.e. with a lower air flow intensity), and the removal unit 24 (here: a suction device) can remove cut dry film residues from the carrier roller 3 more easily and with less energy expenditure (i.e. with a lower suction flow intensity).

[0130] Figure 5 shows a further embodiment of a method according to the invention or of a system according to the invention for producing a dry film, which is essentially identical to the embodiment shown in Figure 1. The upper illustration is in the direction of view of the carrier roller 3 and the counter-roller 4 along the carrier roller rotation axis, and the lower illustration is in the direction of view of the side on which the processing devices 7, 8 are arranged. One difference from the embodiment of Figure 1 is that the additional processing devices 15, 16 are omitted.A further difference is that a first outer segment 25 of the counter roll 4, which is arranged in a direction perpendicular to the carrier roll rotation axis TR opposite the first outer segment of the carrier roll 3, and a second outer segment 26 of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis TR opposite the second outer segment of the carrier roll 3, has a surface finish to which the dry film does not adhere. Here, the surface finish of the first outer segment 25 of the counter roll 4 and / or the second outer segment 26 of the counter roll 4 is designed as a recessed surface of the counter roll 4, wherein the recessed surface preferably has a radius that is <99.9% of the radius that the counter roll 4 has in a first region 27 of an inner segment of the counter roll 4.This embodiment has the advantage of preventing dry film from adhering to segments of the carrier roller 3 to which no dry film should adhere. A dry film that does not adhere to these segments of the carrier roller 3 can be fed back (as a dry powder mixture) to the first calender nip 2, which makes the process more efficient and can also shorten maintenance intervals for the processing devices 7, 8. In the embodiment shown, the carrier roller also has a second region 28 of the inner segment, which is designed like the first and / or second outer segment of the carrier roller, i.e., in particular, has a recessed surface with a radius that is < 99.9% of the radius that the counter roller 4 has in the first region 27 of the inner segment of the counter roller 4. This makes it possible to divide the dry film into two separate dry film bands or dry film strips, i.e.two parallel dry film bands or dry film strips can be produced.

[0131] Figure 6 shows a further embodiment of a method according to the invention or of a system according to the invention for producing a dry film, which is essentially identical to the embodiment shown in Figure 2. The illustration is in the direction of view of the carrier roller 3, the counter roller 4, and the second counter roller 19 along the carrier roller rotation axis. One difference from the embodiment shown in Figure 2 is that the second counter rollers 19 are arranged at an angle to one another. This has the advantage of decoupling the assemblies for film formation and lamination.

[0132] Figure 7 shows a further embodiment of a method according to the invention or of a system according to the invention for producing a dry film. The illustration is in the direction of view of the carrier roll 3, the counter roll 4, the second counter roll 19, the third counter roll 29, and the fourth counter roll 30 along the carrier roll rotation axis. In this embodiment, the radius of the second counter roll 19 and the third counter roll 29 is larger than the radius of the carrier roll 3 and the fourth counter roll 30, which results in the advantage that a higher pressing force can be exerted on the second calender nip 17 and the fourth calender nip 33.

[0133] Figure 8 shows a photograph of a web of a dry film according to the invention, which has a wave-shaped pattern. The wave-shaped pattern extends in the longitudinal direction of the dry film web (from left to right in Figure 8) and extends perpendicular to the longitudinal direction of the dry film web between the essentially straight and essentially mutually parallel boundary lines of the dry film web (from top to bottom in Figure 8, i.e., in the transverse direction of the web), with waves of the wave-shaped pattern having a periodic spacing of approximately 3 mm in the transverse direction of the web.

[0134] Figure 9 shows a schematic plan view of a section of a dry film according to the invention, which is formed in the form of two segments on a current collector foil. The checkered area illustrates the substrate (current collector foil), and the diagonally hatched area illustrates the coating (dry film). The interruptions shown above and below (in white) symbolize that this is a section of a longer band, i.e., a band that extends from the upper part to the lower part of Figure 9 (or in the opposite direction).

[0135] 1: Dry powder mixture;

[0136] 2: first calender gap;

[0137] 3: carrier roller;

[0138] 4: Counter roller;

[0139] 5: first direction of rotation;

[0140] 6: second rotation direction; 7: first processing device (with cutting unit and removal unit);

[0141] 8: second processing device (with cutting unit and removal unit);

[0142] 9: first outer segment of the carrier roller;

[0143] 10: second outer segment of the carrier roller;

[0144] 11: inner segment of the carrier roller;

[0145] 12: first surface finish of the carrier roller (on which the dry film adheres);

[0146] 13: second surface finish of the carrier roller (on which the dry film does not adhere);

[0147] 14: Intermediate area in the inner segment of the carrier roller;

[0148] 15: additional processing device (with cutting unit and removal unit);

[0149] 16: additional processing device (with cutting unit and removal unit);

[0150] 17: second calender nip;

[0151] 18: third calender nip;

[0152] 19: third roller (or second counter roller);

[0153] 20: third rotation direction (rotation direction of the third roller);

[0154] 21: (first) path of the dry film;

[0155] 22: second lane of the dry film;

[0156] 23: Cutting unit (e.g. air nozzle);

[0157] 24: distance unit (e.g. extractor);

[0158] 25: first outer segment of the counter roll with small radius;

[0159] 26: second outer segment of the counter roll with small radius;

[0160] 27: first area of ​​an inner segment of the counter roll with a large radius;

[0161] 28: second area of ​​the inner segment of the counter roll with small radius;

[0162] 29: fourth roller (or third counter roller);

[0163] 30: fifth reel (or fourth counter reel);

[0164] 31: fourth rotation direction (rotation direction of the fourth roller);

[0165] 32: fifth rotation direction (rotation direction of the fifth reel);

[0166] 33: fourth calender gap;

[0167] 34: fifth calender nip; TR: carrier roll rotation axis;

[0168] GR: Counter roll rotation axis;

[0169] 2GR: second counter roll rotation axis (e.g. rotation axis of a second carrier roll); 3GR: third counter roll rotation axis (e.g. rotation axis of a third

[0170] counter roller);

[0171] 4GR: fourth counter roll rotation axis (e.g. rotation axis of a fourth counter roll).

Claims

Patent claims 1. A method for producing a dry film, comprising feeding a dry powder mixture and / or a dry mix into a first calender nip formed by a carrier roller and a first counter roller, wherein the carrier roller rotates about a carrier roller rotation axis at a first peripheral speed in a first rotational direction and the counter roller rotates about a counter roller rotation axis at a second peripheral speed that is lower than the first peripheral speed in a second rotational direction, wherein the second rotational direction is opposite to the first rotational direction, wherein the dry powder mixture and / or the dry mix passes through the first calender nip in a conveying direction, thereby forming a dry film supported at least in regions on the carrier roller, characterized in that at least one first processing device is used,which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a first outer segment of the carrier roller, and at least one second processing device is used, which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a second outer segment of the carrier roller, wherein the carrier roller has an inner segment between the first outer segment and the second outer segment in a direction parallel to the carrier roller rotation axis, wherein the first and second processing devices are each suitable for removing regions of the dry film that are mounted on the outer segments of the carrier roller on the carrier roller.

2. Process according to the preceding claim, characterized in that the dry film is transferred during the process to a sub- strat is laminated, wherein the substrate preferably has at least in some regions a primer layer for reinforced bonding of the dry film, a three-dimensional structure, a texturing and / or a porous layer, wherein particularly preferably i) the primer layer contains or consists of a polymer and an electrically conductive material, has a thickness in the range of <10 pm, preferably <2 pm, and / or is arranged in regions on the substrate which are opposite the inner segment of the carrier roller, in a direction perpendicular to the carrier roller rotation axis; and / or ii) the substrate contains or consists of a woven fabric, nonwoven fabric and / or expanded metal as a three-dimensional structure; and / or iii) the texturing was produced by etching treatment, sandblasting treatment and / or laser treatment, wherein the texturing is present in particular on a surface of the substrate which faces the dry film;and / or iv) the porous layer contains or consists of an electrode layer and / or particle layer; 3. Method according to one of the preceding claims, characterized in that the inner segment of the carrier roller has, at least in some regions, a surface finish to which the dry film adheres, wherein i) the first outer segment and / or second outer segment of the carrier roller has a surface finish to which the dry film does not adhere, wherein this surface finish is preferably designed as a smooth surface of the carrier roller, wherein the smooth surface preferably has a mean roughness Ra that is < 50% of the mean roughness that the carrier roller has in the inner segment, wherein the smooth surface particularly preferably has a mean roughness Ra in the range from 0.005 pm to 1 pm; and / or ii) a first outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the first outer segment of the carrier roll and / or a second outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the second outer segment of the carrier roll, has a surface finish to which the dry film does not adhere, wherein the surface finish of the first outer segment of the counter roll and / or of the second outer segment of the counter roll is preferably designed as a) a recessed surface of the counter roll, wherein the recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roll has in a first region of an inner segment of the counter roll;and / or b) is designed as a coating, preferably as a coating containing or consisting of DLC and / or PTFE, of the first outer segment of the counter roll and / or the second outer segment of the counter roll, which leads to an adhesion to the counter roll of at least 1 wt.% less dry film, in particular at least 10 wt.% less dry film, than in the inner segment of the carrier roll, preferably no adhesion to the counter roll, wherein the inner segment of the carrier roll optionally has a coating and / or texturing to which the dry film adheres, wherein the coating particularly preferably contains or consists of a material selected from the group consisting of PTFE, DLC, tungsten carbide, hard chromium and combinations thereof, wherein the carrier roll optionally has at least a second region of the inner segment which is designed like the first and / or second outer segment of the carrier roll.; 4. Method according to one of the preceding claims, characterized in that the first and second processing devices each have i) a cutting unit which is used to separate a region of the dry film which is mounted on the carrier roller at the respective outer segments of the carrier roller from a region of the dry film which is mounted on the carrier roller at the inner segment of the carrier roller by cutting, wherein the cutting unit is preferably selected from the group consisting of a roller cutter, air nozzle, laser, and combinations thereof; and / or ii) a removal unit which is used to remove a region of the dry film which is mounted on the carrier roller at the respective outer segments of the carrier roller, wherein the removal unit is preferably selected from the group consisting of an air nozzle, scraper, brush, vacuum cleaner, and combinations thereof;and / or iii) a further removal unit used to remove a region of the dry film that is perpendicular to the coating direction in order to realize a coating intermittent in the coating direction; 5. Method according to one of the preceding claims, characterized in that the inner segment of the carrier roller is divided into at least two inner segment regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and an intermediate region is arranged between each two adjacent inner segment regions, the boundary of which is defined in the direction of the rotational axis of the carrier roller by two opposite boundary lines of the 2n boundary lines, where i) the at least two inner segment regions have a surface quality to which the dry film adheres and the intermediate region preferably has a surface finish to which the dry film does not adhere; and / or ii) in a direction perpendicular to the carrier roller rotation axis, opposite each intermediate region of the inner segment, a further processing device is used, each of which is suitable for removing regions of the dry film that are mounted on the carrier roller in the intermediate region of the carrier roller, at least by cutting, wherein each further processing device particularly preferably has a cutting unit that is used to detach a region of the dry film that is mounted on the carrier roller at the respective intermediate regions of the carrier roller from a region of the dry film that is mounted on the carrier roller at the inner segment of the carrier roller, by cutting, wherein the cutting unit is preferably selected from the group consisting of a roller knife, air nozzle, laser, and combinations thereof;and / or a removal unit used to remove a portion of the dry film supported on the carrier roller at the respective intermediate portions of the carrier roller, wherein the removal unit is preferably selected from the group consisting of air nozzle, scraper, brush, vacuum cleaner and combinations thereof; 6. Method according to one of claims 4 or 5, characterized in that the removal unit, optionally also the further removal unit, is used to feed removed areas of the dry film to the first calender gap, optionally first i) to feed them to a dry mix, which is processed to a dry powder mix, which is then fed to the first calender gap, wherein the processing to a dry powder mix preferably comprises a treatment selected from the group consisting of extruder treatment, jet mill, Pin mill, impact mill, mortar mill, roller mill and combinations thereof; or ii) to a dry powder mixture and / or a dry mix, which is then fed to the first calender nip, wherein the proportion of the fed, removed regions of the dry film is preferably at least 0.1% by weight, more preferably at least 1% by weight, most preferably at least 10% by weight, based on the total proportion of the dry powder mixture and / or the dry mix.

7. Method according to one of the preceding claims, characterized in that the first calender nip i) has a length of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm, optionally a maximum of 3000 mm; and / or ii) has a mask and / or a hopper arranged above the calender nip, wherein the mask preferably reduces the application of an amount of dry powder mixture and / or dry mixture at least to the two opposite outer segments of the carrier roll, optionally also to at least one intermediate region of the inner segment of the carrier roll.

8. The method according to one of the preceding claims, characterized in that the carrier roller and / or counter roller a) has a diameter which is < 100 cm, optionally between 10 cm and 100 cm, particularly preferably < 50 cm, optionally between 10 cm and 50 cm, in particular < 30 cm; and / or b) has a width, in a direction perpendicular to the roller axis of the carrier roller and / or counter roller, of > 30 cm, preferably > 60 cm, particularly preferably > 100 cm, in particular a maximum of 300 cm.

9. The method according to any one of the preceding claims, characterized in that laminating the dry film onto a substrate comprises the following steps: i) conveying the dry film on the carrier roll into a second calendering nip formed by the carrier roll and a second counter roll, wherein the second counter roll rotates about a second counter roll rotation axis at a second peripheral speed which is higher than the first peripheral speed of the carrier roll or equal to the first peripheral speed of the carrier roll, in a third direction of rotation, wherein the third direction of rotation is opposite to the first direction of rotation; ii) optionally conveying the dry film together with the substrate further through at least one third, preferably further at least one fourth, particularly preferably further at least one fifth, in particular further at least one sixth, calendering nip;iii) Optionally, conveying the dry film without substrate by transfer due to increased peripheral speeds through at least one third, preferably at least one fourth, particularly preferably at least one fifth, in particular at least one sixth, calender nip; whereby a substrate laminated with the dry film is formed.; 10. Plant for producing a dry film, comprising a) a device configured to produce a dry film from a dry powder mixture and / or a dry mixture, wherein the device includes a carrier roller and a first counter roller, wherein the carrier roller and the counter roller form a first calender nip for feeding a dry powder mixture and / or a dry mixture, wherein the carrier roller is suitable for rotating about a carrier roller rotation axis and the counter roller is suitable for rotating about a counter roller rotation axis; b) a control unit which is at least configured to cause the carrier roll to rotate about its carrier roll rotation axis at a first circumferential speed in a first rotation direction and the counter roll to rotate about its counter roll rotation axis at a second circumferential speed which is lower than the first circumferential speed in a second rotation direction, wherein the second rotation direction is opposite to the first rotation direction, wherein the control unit is in particular configured to adjust a gap width of the calender gap and / or a contact pressure in the calender gap between the carrier roll and the first counter roll;characterized in that the system has at least one first processing device which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a first outer segment of the carrier roller and at least one second processing device which is arranged in a direction perpendicular to the carrier roller rotation axis opposite a second outer segment of the carrier roller, wherein the carrier roller has an inner segment between the first outer segment and the second outer segment in a direction parallel to the carrier roller rotation axis, wherein the first and second processing devices are each suitable for removing regions of the dry film which are mounted on the outer segments of the carrier roller on the carrier roller, at least by cutting.; 11. Plant according to claim 10, characterized in that the plant contains a substrate and is configured to laminate the dry film onto the substrate, wherein the substrate preferably has at least in regions a primer layer for reinforced bonding of the dry film, a three-dimensional structure, a texturing and / or a porous layer, wherein particularly preferably i) the primer layer contains or consists of a polymer and an electrically conductive material, has a thickness in the range of <10 pm, preferably <2 pm, and / or in regions on the Substrate is arranged opposite the inner segment of the carrier roller in a direction perpendicular to the carrier roller rotation axis; and / or ii) the substrate contains or consists of a woven fabric, nonwoven fabric and / or expanded metal as a three-dimensional structure; and / or iii) the texturing was produced by etching treatment, sandblasting treatment and / or laser treatment; and / or iv) the porous layer contains or consists of an electrode layer and / or particle layer.

12. System according to one of claims 10 or 11, characterized in that the inner segment of the carrier roller has, at least in some regions, a first surface quality to which the dry film adheres, wherein i) the first outer segment and / or second outer segment of the carrier roller has a second surface quality to which the dry film does not adhere, wherein this surface quality is preferably designed as a smooth surface of the carrier roller, wherein the smooth surface preferably has a mean roughness Ra that is < 50% of the mean roughness value that the carrier roller has in the inner segment, wherein the smooth surface particularly preferably has a mean roughness Ra in the range from 0.001 pm to 1 pm;and / or iii) a first outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the first outer segment of the carrier roll and / or a second outer segment of the counter roll, which is arranged in a direction perpendicular to the carrier roll rotation axis opposite the second outer segment of the carrier roll, has a surface finish to which the dry film does not adhere, wherein the surface finish of the first outer segment of the counter roll and / or the second outer segment of the counter roll is preferred; a) a recessed surface of the counter roll is designed, wherein the recessed surface preferably has a radius which is < 99.9%, preferably < 99%, particularly preferably < 95%, in particular < 90%, of the radius which the counter roll has in a first region of an inner segment of the counter roll; and / or b) is designed as a coating, preferably as a coating containing or consisting of DLC and / or PTFE, of the first outer segment of the counter roll and / or the second outer segment of the counter roll, which coating results in an adhesion to the counter roll of at least 1 wt.% less dry film, particularly at least 10 wt.-% less dry film than in the inner segment of the carrier roller, preferably no adhesion to the counter roller, wherein the inner segment of the carrier roller optionally has a coating and / or texturing to which the dry film adheres, wherein the coating particularly preferably contains or consists of a material selected from the group consisting of PTFE, DLC, tungsten carbide, hard chromium and combinations thereof, wherein the carrier roller optionally has at least a second region of the inner segment which is designed like the first and / or second outer segment of the carrier roller.

13. Plant according to one of claims 10 to 12, characterized in that the first and second processing devices each have i) a cutting unit configured to separate a portion of the dry film, which is mounted on the respective outer segments of the carrier roller on the carrier roller, from a portion of the dry film, which is mounted on the inner segment of the carrier roller on the carrier roller, by cutting, wherein the cutting unit is preferably selected from the group consisting of a roller knife, air nozzle, laser, and combinations thereof; and / or ii) have a removal unit configured to remove a portion of the dry film supported on the respective outer segments of the carrier roller, wherein the removal unit is preferably selected from the group consisting of air nozzle, scraper, brush, suction device, and combinations thereof; and / or iii) have a further removal unit configured to remove a portion of the dry film that runs perpendicular to the coating direction in order to realize a coating intermittent in the coating direction.

14. System according to one of claims 10 to 13, characterized in that the inner segment of the carrier roller is divided into at least two inner segment regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and in each case between two adjacent inner segment regions an intermediate region is arranged, the boundary of which is defined in the direction of the axis of rotation of the carrier roller by two opposite boundary lines of the 2n boundary lines, where i) the at least two inner segment regions have a surface quality to which the dry film adheres and the intermediate region preferably has a surface quality to which the dry film does not adhere;and / or ii) the system, in a direction perpendicular to the carrier roller rotation axis, opposite each intermediate region of the inner segment, has a further processing device each suitable for removing regions of the dry film that are mounted on the carrier roller in the intermediate region of the carrier roller, at least by cutting, wherein each further processing device particularly preferably has a cutting unit that is configured to remove a region of the dry film that is mounted on the carrier roller at the respective intermediate regions of the carrier roller from a region; of the dry film, which is mounted on the inner segment of the carrier roller, by cutting, wherein the cutting unit is preferably selected from the group consisting of a roller blade, air nozzle, laser, and combinations thereof; and / or having a removal unit configured to remove a portion of the dry film, which is mounted on the carrier roller at the respective intermediate portions of the carrier roller, wherein the removal unit is preferably selected from the group consisting of a scraper, brush, vacuum cleaner, and combinations thereof.

15. Plant according to one of claims 13 or 14, characterized in that the removal unit, optionally also the further removal unit, is configured to feed removed areas of the dry film to the first calender nip, optionally initially i) to feed them to a dry mix which is processed into a dry powder mix, wherein a processing device of the plant is configured to process the dry mix into a dry powder mix and to feed it to the first calender nip, wherein the processing device is preferably selected from the group consisting of extruder, jet mill, pin mill, impact mill, mortar mill, roller mill and combinations thereof;or ii) first feeding removed regions of the dry film to a dry powder mixture and / or a dry mix, wherein the plant is configured to feed the dry powder mixture and / or the dry mix to the first calender nip, wherein the proportion of the fed, removed regions of the dry film is preferably at least 0.1 wt.%, particularly preferably 1 wt.%, very particularly preferably 10 wt.%, with respect to the total proportion of the dry powder mixture and / or the dry mix; 16. Plant according to one of claims 10 to 15, characterized in that the first calender nip i) has a width of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm; and / or ii) has a mask and / or a hopper arranged above the calender nip, wherein the mask is preferably suitable for reducing the application of a quantity of dry powder mixture and / or dry mixture at least to the two opposite outer segments of the carrier roll, optionally also to at least one intermediate region of the inner segment of the carrier roll.

17. Plant according to one of claims 10 to 16, characterized in that the carrier roller and / or counter roller a) has a diameter which is < 100 cm, optionally between 10 cm and 100 cm, particularly preferably < 50 cm, optionally between 10 cm and 50 cm, in particular < 30 cm; and / or b) has a width, in a direction perpendicular to the roller axis of the carrier roller and / or counter roller, of > 30 cm, preferably > 60 cm, particularly preferably > 100 cm, in particular a maximum of 300 cm.

18. Plant according to one of claims 10 to 17, characterized in that the plant i) contains a second counter roll, which forms a second calender nip with the carrier roll, wherein the plant is configured to convey the dry film on the carrier roll into the second calender nip, wherein the control unit is configured to cause the second counter roll to rotate about a second counter roll rotation axis at a second peripheral speed, which is higher than the first peripheral speed of the carrier roll or is equal to the first peripheral speed of the carrier roll, in a third rotational direction, wherein the third rotational direction is opposite to the first rotational direction; ii) optionally further comprises at least one third, preferably further at least one fourth, particularly preferably further at least one fifth, most particularly preferably at least one sixth, in particular further at least one seventh, roller;iii) is optionally configured to convey the dry film together with a substrate through at least one third, preferably further at least one fourth, particularly preferably further at least one fifth, in particular further at least one sixth, calender nip, which is formed by two rollers in each case, wherein the two rollers are optionally arranged linearly or at an angle to one another and / or have a radius of different sizes, wherein the control unit of the system is in particular configured to set a gap width of the calender nip between the respective two rollers and / or to set a contact pressure in the respective calender nips between the respective two rollers;and iv) is optionally configured to convey the dry film without substrate by transfer due to increased peripheral speeds through at least one third, preferably at least one fourth, particularly preferably at least one fifth, in particular at least one sixth, calender nip.; 19. Dry film which is arranged as at least one web, preferably a plurality of parallel webs, on a substrate, wherein the at least one web, preferably each of the plurality of parallel webs, is defined in a longitudinal direction of the web(s) by two boundary lines, characterized in that the boundary lines run substantially straight and substantially parallel to one another, wherein a distance between the respective two boundary lines along the longitudinal direction varies by < 1000 pm, preferably < 500 pm, particularly preferably < 200 pm.

20. Dry film according to claim 19, characterized in that the at least one web, preferably each of the plurality of parallel webs, i) in the longitudinal direction of the web(s), has a length of at least 0.1 m, preferably at least 0.5 m, particularly preferably at least 1 m, very particularly preferably at least 5 m, in particular at least 10 m; and / or ii) perpendicular to the longitudinal direction of the web(s) has a width of at least 200 mm and / or a maximum of 1200 mm, preferably a width in the range from 250 mm to 650 mm, particularly preferably a width in the range from 250 to 350 mm;and / or iii) have a wave-shaped pattern which extends in the longitudinal direction of the web(s) of the dry film and extends perpendicular to the longitudinal direction of the web(s) between the substantially straight and substantially mutually parallel boundary lines of the web(s) of the dry film, wherein waves of the wave-shaped pattern preferably have a periodic spacing in the transverse direction of the web(s) in the range of > 0 mm and <10 mm, preferably in the range of > 0 mm and <5 mm; wherein the dry film is optionally arranged on the substrate as at least two parallel webs, preferably as at least three parallel webs, particularly preferably as at least four parallel webs, in particular as at least five parallel webs.; 21. Dry film according to one of claims 19 or 20, characterized in that between the dry film and the substrate, at least in some regions, a primer layer is arranged, which contacts both the dry film and the substrate, wherein preferably i) the primer layer contains or consists of a polymer and an electrically conductive material and / or has a thickness in the range of <10 pm, particularly preferably in the range of <2 pm; and / or ii) the substrate has or consists of a three-dimensional structure, which preferably contains or consists of a woven fabric, nonwoven fabric and / or expanded metal; and / or iii) the substrate has a texturing, which was preferably produced by etching treatment, sandblasting treatment and / or laser treatment, wherein the texturing is present in particular on a surface of the substrate facing the dry film; and / or iv) the substrate has or consists of a porous layer, wherein the porous layer preferably contains or consists of an electrode layer and / or particle layer.

22. Dry film according to one of claims 19 to 21, characterized in that the dry film contains an active material of an electrode of a battery, wherein the active material is preferably i) selected from the group consisting of active material for a cathode of a battery and active material of an anode for a battery, wherein the active material is particularly preferably selected from the group consisting of lithium iron phosphate, lithium manganese iron phosphate, lithium manganese oxide, lithium nickel manganese cobalt oxide, nickel-rich lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminum oxide, lithium cobalt oxide, lithium manganese nickel oxide, high-voltage spinel, carbon, sulfur, graphite, hard carbon, silicon, tin, silicon oxide, lithium, indium lithium titanate, sodium-containing compounds based on metal oxides, polyanions, analogues of Prussian blue and combinations thereof; and / or ii) in a mass fraction of >50 wt.%, preferably >70 wt.-%, particularly preferably >90 wt.%, based on the total mass of the dry film, is contained in the dry film. i) has a liquid content of <1 vol.%, based on the total volume of the dry film.

23. The dry film according to any one of claims 19 to 22, characterized in that the dry film contains an electrically conductive additive, wherein the electrically conductive additive is preferably i) selected from the group consisting of carbon nanotubes, carbon particles, graphite, graphene, porous carbons, and combinations thereof; and / or ii) contained in the dry film in a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.%, particularly preferably 1-4 wt.%, based on the total mass of the dry film.

24. Dry film according to one of claims 19 to 23, characterized in that the dry film contains a non-fibrillated material which exerts a binder effect, wherein the material is preferably i) selected from the group consisting of fluoropolymer, carboxymethylcellulose, styrene-butadiene rubber, biopolymer, polyolefin, polypeptide, polyamide, polyacrylate, and mixtures thereof; and / or ii) in a mass fraction of 0.1-10 wt.%, preferably 0.5-5 wt.%, particularly preferably 0.5-4 wt.%, based on the total mass of the dry film.

25. Dry film according to one of claims 19 to 24, characterized in that the dry film contains a fibrillated material which has a binding effect, wherein the fibrillated material is preferably i) selected from the group consisting of fibrillated polypeptide, fibrillated plastic and mixtures and combinations thereof, wherein the fibrillated material is particularly preferably fibrillatable PTFE with a molecular weight of >10 6 g / mol, most preferably >10 7 g / mol, and / or ii) in a mass fraction of >1 wt.%, preferably >10 wt.%, particularly preferably >50 wt.%, based on the total mass of the dry film, in which the dry film is contained; and / or iii) contains or consists of thread-like structures having a diameter in the range of 0.001 µm to 1 µm and / or a length in the range of 1 µm to 100 µm; and / or iv) is isotropically distributed in the dry film; and / or v) is anisotropically oriented distributed in the dry film.

26. Dry film according to one of claims 19 to 25, characterized in that the dry film contains an ion-conducting substance, wherein the ion-conducting substance is preferably i) selected from the group consisting of ion-conducting solids, gel-like ion conductors, salt-like ion conductors, and mixtures thereof, wherein the ion-conducting solids are preferably selected from the group consisting of sulfidic solid ion conductors, glass-like solid ion conductors, polymeric solid ion conductors, ceramic solid ion conductors, and mixtures thereof; and / or ii) in a mass fraction of 1-99 wt.%, preferably 5-30 wt.%, particularly preferably 10-20 wt.%, based on the total weight of the dry film, in which the dry film is contained.

27. Dry film according to one of claims 19 to 26, characterized in that the dry film i) has a thickness in the range of 5 pm to 500 pm, preferably in the range of 10 pm to 150 pm, particularly preferably in the range of 30 pm and 100 pm, very preferably in the range of 40 pm and 70 pm; and / or ii) has a liquid content of <1 vol.%, based on the total volume of the dry film; and / or iii) has a porosity of 15-80%, preferably of 20-50%, particularly preferably of 25-35%, or a porosity of 0.1-25%, preferably 0.1-10%, particularly preferably 0.1-5%.

28. Dry film according to one of claims 19 to 27, characterized in that it is produced by a process according to one of claims 1 to 9.

29. A battery comprising a) an electrode comprising a dry film according to any one of claims 19 to 28; b) a counter electrode; and c) an electrolyte, preferably a solid electrolyte, arranged between the electrode and the counter electrode.

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