Battery manufacturing method and system

Abstract

A method of manufacturing a battery, particularly a secondary battery, is disclosed. An active material is applied onto a substrate. An insulator material is applied onto the substrate, for example, such that it extends over an interface between the active material and the substrate. The insulator material includes an insulator component and a liquid component. An indicative wet thickness of the insulator material is determined at a location on the substrate offset from the interface by a characteristic measurement distance. Application of the insulator material is adapted as a function of the indicative wet thickness.

Description

[Technical field]

[0001] The present invention relates to battery manufacturing methods and systems, in particular to methods that may be performed to form battery electrodes and systems operable to form battery electrodes. [Background technology]

[0002] A battery electrode generally comprises an active material deposited on a (conductive) substrate, which may be an electrically conductive plate. In some manufacturing processes or systems, an insulating coating may be provided that covers a portion of the conductive substrate along the boundary (which may also be referred to as the edge, edge portion, periphery, or similar name) of the active material deposited on the substrate. Such an insulating coating may ensure sufficient electrical insulation of the conductive substrate, which may be used, for example, as a current collector for the battery electrode.

[0003] With this in mind, it may be advantageous to precisely control the application of the insulating coating with respect to the thickness of the insulating coating applied on the substrate, and with respect to the material present on the substrate, particularly the portion of the insulating coating that is applied to the active material of the electrodes of the battery. Thus, a technical challenge may relate to optimizing the thickness and location of the insulating coating applied on the substrate.

[0004] As used herein, the terms "system," "battery manufacturing system," and "system for manufacturing a battery" may be used interchangeably. Also, the terms "method," "battery manufacturing method," and "method for manufacturing a battery" may be used interchangeably. The methods disclosed herein may be performed in an automated manner. For such purposes, the methods may be provided, for example, as a sequence of instructions on / in a machine-readable medium to be executed by a processor.

[0005] A battery manufacturing system as disclosed herein may be configured to perform the battery manufacturing method disclosed herein, selectively including any of the features and method steps. Thus, when any feature of the battery manufacturing method is described, such feature may also be applied to the corresponding battery manufacturing system and / or combined with the corresponding battery manufacturing system feature. Similarly, when one feature of the battery manufacturing system is described, such feature may also be applied to the corresponding battery manufacturing method and / or combined with the corresponding battery manufacturing method feature. In particular, the features of the battery manufacturing method and the features of the battery manufacturing system are not mutually limiting, unless otherwise expressly stated or technically inappropriate. Pursuant to this understanding, the battery manufacturing method and the battery manufacturing system may be described in combination for simplicity of description.

[0006] The battery as referred to herein may be or include a general electrochemical cell for energy storage. More specifically, the battery as referred to herein may be or include a secondary battery and / or a primary battery. In this specification, a secondary battery may refer to or include a rechargeable battery. In particular, the battery may include one or more layers of electrodes and one or more layers of separators stacked (e.g., wound up) in a particular manner. The battery may be or include a coin-type, cylindrical, prismatic, or pouch-type battery. In a particular example, the battery may be configured to power a machine or device that is off the power grid, such as an electric vehicle, a mobile device, or the like.

[0007] In addition, terms and expressions in parentheses are used in this specification to avoid repetition of explanations. Such terms and expressions in parentheses may indicate alternative terms or alternative expressions that may be used alternatively or additionally in the respective clauses.

[0008] Generally, battery manufacturing as referred to herein also considers the manufacture of prototypes of batteries. Nevertheless, in the following, reference may be made to a "one" battery, which thus refers to the manufacture of one of a plurality of identical batteries, without limiting the subject matter generally to the manufacture of any one particular concrete battery. In particular, the subject matter as claimed may envisage the automated (mass) production of batteries. Summary of the Invention [Problem to be solved by the invention]

[0009] The problem to be solved from the known prior art may be solved by the subject matter as defined in the independent claims. Particular embodiments are given by the features of the dependent claims. [Means for solving the problem]

[0010] A method for manufacturing a battery, in particular a secondary battery, is provided. The method may include the following steps, which may be performed in the following order, but are not bound to that particular order:

[0011] applying an active material onto the substrate; For example, applying an insulator material onto the substrate so as to extend over an interface between the active material and the substrate and / or onto the active material, the insulator material including an insulator component and a liquid component; determining an indicative wet thickness of the dielectric material at a location on the substrate offset from the boundary by a characteristic measurement distance; Adapting the step of applying the insulator material as a function of the index wet thickness.

[0012] After application of the insulating material, the liquid component of the insulating material evaporates during the manufacturing process of the battery, leaving the insulating component of the insulating material as applied. In some conventional methods and systems, the thickness and position of the remaining insulating component can be inspected after the liquid component of the insulating material evaporates. If the results are not satisfactory, the application of the insulating material can be modified (adapted), the entire preparation process including application and evaporation can be repeated, and the thickness and position of the remaining insulating component can be inspected again. Such a procedure requires a lot of time, energy, and materials.

[0013] In view of this, the battery manufacturing method and battery manufacturing system disclosed herein allows the indicator wet thickness of the insulating material to be determined in real time. The claimed subject matter exploits the fact that there is a correlation between the thickness of the remaining insulating component of the insulating material and the indicator wet thickness of the insulating material. Thus, the thickness of the insulating component of the insulating material remaining on the substrate after evaporation of the liquid component of the insulating material can be estimated from the determined indicator wet thickness. In this manner, the battery manufacturing method and battery manufacturing system disclosed herein allows for real-time estimation of the thickness of the solid insulating coating on the substrate. This can also be applied to the interface between the active material and the substrate, as well as the application of the solid insulating coating on the active material applied on the substrate.

[0014] The battery manufacturing methods and systems disclosed herein also allow the application of insulator material to be adapted as a function of the determined index wet thickness, allowing for precise real-time control of the application of a solid insulating coating on the substrate. This may also apply to the application of a solid insulating coating on the active material applied on the substrate, as well as to the interface between the active material and the substrate. As a result, the battery manufacturing methods and systems disclosed herein may allow for precise control of the application of insulator material in a manner that saves materials, costs, time, and energy.

[0015] As mentioned, the battery may include an electrode, which may be a positive electrode or a negative electrode. The electrode may include a substrate and an active material applied onto the substrate. The active material may be specially prepared for each type of electrode. For example, the active material may include lithium for a positive electrode. In general, the term "application" as used herein refers to providing one material onto another material in any suitable manner, unless otherwise specifically indicated. For example, application may be or include ejecting the material from an ejector, for example by squeezing through a die or extrusion using an extrusion setup. In other examples, application may be or include spraying the material onto a target surface, whereby the ejector may be considered to include a nozzle or nozzle array. In particular, application may refer to the supply of active material onto the substrate and the supply of insulator material onto the substrate (and, if applicable, onto the active material).

[0016] After application, the active material may occupy a partial area of ​​the surface of the substrate on which it is applied. Thus, the applied active material extends to the boundary. The boundary may refer to the material boundary between the active material and the surface when viewed from a plane on the substrate. The active material may be a flowable material mixture, and thus, the applied active material may spread to the boundary. The boundary may correspond to the edge of the active material applied on the substrate, and the terms "boundary" and "edge" may be used interchangeably herein, unless otherwise indicated or technically inappropriate. Additionally, in this specification, an edge portion may refer to a portion of the active material along and near a boundary or edge. As explained below, an edge portion may be defined by a sliding or sliding portion. In this specification, the term "boundary" is used to specifically refer to the boundary between the substrate and the applied active material, unless otherwise indicated.

[0017] In this specification, the active material applied on the substrate may be referred to as the applied active material. The boundary between the applied active material and the substrate may be substantially linear along a particular direction, particularly along the process direction. However, the applied active material may be a flowable material mixture, and therefore may not be perfectly linear by definition, but may form a boundary substantially or generally or on average aligned with a straight line, particularly parallel to the process direction. In this specification, the process direction may be the direction in which the substrate is moved while the active material and / or the insulator material are applied onto the substrate.

[0018] The edge portion of the applied active material may exhibit so-called sliding, in which the thickness of the applied active material decreases smoothly outward, and / or may form a sliding portion. Also, depending on the sliding and / or at the sliding portion, the upper surface of the opposite side of the substrate may be curved concavely (protrude upward). The sliding or sliding portion may occur due to the properties of the active material, such as flowability, viscosity, surface tension, and / or friction against the surface of the substrate.

[0019] The methods and systems disclosed herein may each be performed and operable to manufacture a battery, particularly a secondary battery, including an electrode. In this context, the substrate may serve as a current collector for the electrode of the battery. The substrate may be an electrically conductive substrate. The substrate may be or include a conductive material, such as, for example, a conductive metal, such as aluminum, its alloys, copper or its alloys, or a conductive metal alloy. The substrate may have the shape of a plate, sheet, foil, film, layer, or the like. The substrate may have a substantially flat upper surface on which active material and / or insulator material is applied. For simplicity of explanation, expressions such as upper surface, top side, upward, on, and the like are used to indicate the normal direction of the major surface of the substrate on which active material and / or insulator material is applied.

[0020] The active material of the battery may be provided as a viscous mixture, which may also be referred to as a slurry. The active material coated on the electrode substrate is then dried and selectively activated to obtain an electrode for the battery. In the following, the term "battery" may be or may include a secondary battery. For simplicity of explanation, the expression "active material" may also refer hereinafter to a slurry that includes the active material and additional components in a viscous and / or flowable mixture, unless otherwise specified or technically inappropriate.

[0021] The active material may, for example, include lithium-cobalt-oxide (LCO), lithium nickel cobalt manganese oxide (NCM), lithium nickel cobalt aluminum oxide (NCA), lithium manganese oxide (LMO), lithium nickel manganese spinel (LNMO), lithium iron phosphate (LFP). The active material may also include graphite, lithium, or silicon. The active material may additionally include solid components, in particular solid conductive particles, for example carbon black or carbon nanotubes. The active material may additionally include a dispersant.

[0022] The active material may include a binder with which the solid material is mixed. The binder may be a polymeric binder. The (polymeric) binder of the active material may include polyvinylidene fluoride (PVDF), polymethyl acrylate (PMMA), carboxymethylcellulose (CMC), polyacrylate, xanthan gum, polyethylene glycol, or styrene butadiene. The active material may further include a liquid component. The liquid component of the active material may include water or an organic solvent, such as tetrahydrofuran (THF) or N-Methyl-2-pyrrolidon (NMP).

[0023] As noted above, the insulator material may include an insulator component and a liquid component. In particular, the insulator material may be or include a mixture of an insulator component and a liquid component, the mixture being prepared as a flowable or viscous mixture of the liquid component and the insulator component. In certain instances, the insulator material may be prepared by mixing the insulator component with the liquid component.

[0024] The liquid component may be any suitable liquid material that can be mixed with the insulator component. In particular, the liquid component may be selected and / or prepared, for example, to provide a homogeneous (or heterogeneous) mixture with the insulator component. The liquid component of the insulator material may be or may include water or an aqueous liquid, or an organic solvent, such as tetrahydrofuran (THF), or N-Methyl-2-pyrrolidon (NMP).

[0025] The boiling point of the liquid component of the insulating material may be lower than the boiling point of the insulating component of the insulating material (at the same pressure and under the same other environmental conditions). Thus, the liquid component may evaporate when exposed to an elevated temperature, while the insulating component remains. The remaining insulating component may be additionally treated to obtain an insulating coating. Alternatively or additionally, the treatment of the insulating component may include applying heat, (UV) radiation, or other forms of energy to the insulating material, during which the liquid component evaporates.

[0026] The process of forming an insulating coating from an applied insulator material, and in particular from its insulator components, may be referred to herein as a curing process and / or a drying process, depending on the insulator material. The insulator components and the resulting insulating coatings therefrom may refer to substances and / or structures that provide electrical insulation, for example, by preventing current flow within a voltage range of interest (and / or within an electric field range of interest). For example, the insulator components may be 10 -8 S cm -1 Electrical conductivity below 10 8 It may have an electrical resistivity of Ω·cm or more.

[0027] The insulator component may be or may include a binder, in particular a polymeric binder. A curing and / or drying process may be performed after application of the insulator material on the substrate, in which the (polymeric) binder may be cured (or polymerized) under exposure to heat, (infrared and / or ultraviolet (UV)) radiation or any suitable form of energy input to form an insulating coating. The (polymeric) binder of the insulator material may be or may include polyvinylidene fluoride (PVDF), polymethyl acrylate (PMMA), carboxymethylcellulose (CMC), polyacrylate, xanthan gum, polyethylene glycol, or styrene butadiene.

[0028] Alternatively or additionally, the insulator component may be or include a ceramic material. A curing and / or drying process may be performed after application of the insulator material on the substrate, where the ceramic material may be calcinated or sintered under exposure to heat, (UV) radiation or any suitable form of energy input, or otherwise processed to form a solid insulating coating. Examples of ceramic materials may include oxide-based ceramics, such as aluminum oxide (alumina, Al2O3), zirconium dioxide (zirconia, ZrO2), titanium dioxide (TiO2), magnesium oxide (MgO), zinc oxide (ZnO), barium titanate (BTO), aluminum titanate (tialite, Al2TiO5), and beryllium oxide (beryllia, BeO). Additional examples of insulator components include silicate-based materials, kaolinite, boron carbide (B4C), silicon carbide (SiC), silicon nitride (SiN), tungsten carbide (WC), molybdenum disilicide (MoSi2), and aluminum nitride (AlN).

[0029] In certain non-exhaustive examples, the insulator component may include one or a combination of the following: PVDF, aluminum oxide hydroxide (AlO(OH), e.g., boehmite or diaspore), SBR-based ceramic material (styrene butadiene rubber), and alumina (Al2O3). The insulator component may also include solid additives, which may include one or a combination of the following: dyes, tannic acid, and dispersants. The component content percentages of the insulator component may be empirically determined and may undergo an ongoing development and optimization process.

[0030] Some of the specific non-exhaustive examples may be as follows: In a specific example, 90%-99.9% of the insulation component may be made of PVDF (e.g., KF9700). In another specific example, 40%-70%, preferably 50%-60%, or more preferably 55%-60%, or 57.5%±1% of the insulation component may be made of aluminum oxide hydroxide, while 25%-60%, preferably 30%-50%, or more preferably 35%-45%, or 40% of the insulation component may be made of SBR. In such a specific example, tannic acid may be added as an additive at a relative content of 0.5%-5%, preferably 1%-4%, or more preferably 2%-3%, or 2.5%±0.2% of the insulation component. In another example, 40%-90%, preferably 50%-80%, more preferably 60%-70%, or 65%±0.5% of the insulator component may be made of alumina (e.g., AES11), while 20%-45%, preferably 25%-35%, more preferably 30%-35%, or 32.5%±0.5% of the insulator component may be made of PVDF (e.g., KF9700). In such a particular example, the dispersant may be added as an additive at a relative content of 1%-6%, preferably 1.5%-5.5%, more preferably 1.8%-3.5%, or 2.5%±0.5% of the insulator component. In additional specific examples, 70%-99%, preferably 75%-95%, more preferably 80%-90%, or 87%±2% of the insulation component may be made of aluminum oxide hydroxide, while 1%-20%, preferably 5%-15%, more preferably 7%-13%, or 10%±1.5% of the insulation component may be made of PVDF (e.g., KF9700). In such specific examples, tannic acid may be added as an additive in a relative content of 1%-6%, preferably 1.5%-5%, more preferably 2.5%-4.5%, or 3.5%±0.5% of the insulation component.

[0031] The battery manufacturing method may include a step of applying an active material on a substrate. The active material may include any of the corresponding features described herein. The substrate may include any of the corresponding features described herein. In this specification, the applying process may be referred to as applying. The applying may be as defined above and may include any of the corresponding features described herein. In particular, applying the active material may be or may include ejecting the active material from an ejector, for example by squeezing through a die, by extrusion, or by spraying the active material onto the substrate.

[0032] As mentioned, the active material may be applied onto the substrate, for example, to occupy a partial area of ​​the surface of the substrate. Thus, the applied active material may extend to the boundary in the width direction. The width direction may be perpendicular to the process direction mentioned above, and perpendicular to the thickness direction in which any thickness as mentioned herein is measured. Both the width direction and the process direction may be parallel to the major surface, which may be referred to as the top surface of the substrate, on which the active material and the insulator material are applied. Thus, the thickness direction may be perpendicular to the top surface of the substrate.

[0033] The boundary may include any of the corresponding features described herein. The boundary may be substantially linear and parallel to the process direction as mentioned above. In particular, the boundary between the applied active material and the substrate may be formed by an end face of the applied active material toward the width direction. More specifically, the boundary between the applied active material and the substrate may be formed by not completely covering the substrate, i.e., by leaving a portion of the substrate uncovered. The material boundary between the uncovered portion of the substrate and the applied active material may be referred to as the boundary.

[0034] As noted, an edge of the applied active material may be formed along a boundary. As such, edge and boundary may be used interchangeably unless otherwise indicated or technically inappropriate. However, an edge of the applied active material may refer to the maximum physical extent of the active material, while a boundary is the material boundary between the applied active material and the substrate. Also, an edge portion of the active material may be as noted and may refer to the three-dimensional portion of the applied active material along and adjacent to a boundary or edge.

[0035] The interface between the applied active material and the substrate may include any of the corresponding features described herein. The edges of the applied active material may include any of the corresponding features described herein. The edge portions of the applied active material may include any of the corresponding features described herein.

[0036] The battery manufacturing method may, for example, include a step of applying an insulator material onto the substrate so as to extend over the interface between the active material and the substrate. The insulator material may include any of the corresponding features described herein. The interface may include any of the corresponding features described herein. The insulator component may include any of the corresponding features described herein. The liquid component may include any of the corresponding features described herein. Also, the application of the insulator material may be essentially the same or similar to the application of the active material described herein. In particular, the application of the insulator material may be or may include ejecting the insulator material from an ejector, for example by squeezing through a die, by extrusion, or by spraying onto the substrate.

[0037] The insulator material may be applied, for example, onto the substrate such that it extends over the interface between the applied active material and the substrate. Thus, the applied insulator material may also extend onto the applied active material. In other words, the insulator material may be applied onto both the substrate and the active material applied onto the substrate. In other words, the applied insulator material may extend from the substrate through the interface onto the active material applied onto the substrate.

[0038] As described above, the insulator material may include an insulator component and a liquid component. The insulator component may include any of the corresponding features described herein. The liquid component may include any of the corresponding features described herein. Thus, the insulating coating may be formed by processing the insulator material according to the configuration of the insulator component and the liquid component of the insulator material.

[0039] The battery manufacturing method may include determining an index wetting thickness of the insulator material at a location on the substrate, such location at which the index wetting location is determined may be offset from the interface between the substrate and the applied active material by a characteristic measurement distance.

[0040] Here, determining any thickness may refer to a physically determined step, rather than an estimation, simulation or calculation. In particular, determining any thickness may include measuring such thickness. Measuring the thickness may be performed using any known and suitable measurement method, for example using an optical measurement setup, in particular using a reflectance spectrometer. Such a reflectance spectrometer may use a light source having a spectrum in the (near) infrared near range and / or in the visible range, or in the wavelength range of 400 nm to 1100 nm. The reflectance spectrometer may illuminate the measurement area, for example with a spot size of 2 mm, in particular with a spot size of 1 mm to 1.5 mm. For such purpose, the reflectance spectrometer may use a collimator to collimate the light from the light source. Also, the reflectance spectrometer may use a motorized shutter. In one example, a portion of the light from the light source is reflected at the incident surface of the target material (i.e. the applied insulator material, the remaining applied material and / or the active material), while another portion of the light is reflected at the interface of the target material and the substrate (also as mentioned herein). Thus, the phase shift between the different reflected portions of the light can be detected and the thickness can be derived therefrom.

[0041] Using a solid measurement probe that penetrates the applied insulating material and / or the applied active material would be another option, however, is not preferred as it may cause structural damage to the insulating coating and / or active material. Although the absolute value of the determined thickness may (or may not) vary depending on the measurement setup, the claimed subject matter is concerned with the characteristic measurement location at which the thickness of the applied insulating material is determined, not the absolute value of the thickness. In other words, as long as the same measurement setup is used to determine the thickness of the applied insulating material and the remaining insulating material, the claimed subject matter is not affected by the particular type of measurement setup used.

[0042] The indicator wet thickness can indicate the thickness of the insulator material at the location, where such location is defined by the property measurement distance from the boundary between the substrate and the applied active material. Such location can also be referred to as the property measurement location. Thus, the property measurement location can be determined / defined by the property measurement distance from the boundary. The indicator wet thickness can be the thickness of the insulator material applied on the substrate at the property measurement location. In this manner, the property measurement distance, the property measurement location and the indicator wet thickness can be interconnected.

[0043] The inventors have discovered that there is a predictable and thereby reproducible relationship between the thickness of the insulating coating obtained by applying and processing the insulating material in the manner referred to above (which may be referred to herein as the dry thickness) and the thickness of the insulating material applied onto the substrate at a particular location (i.e., the indicative wet thickness). Such particular location may be or may correspond to the above-mentioned property measurement location offset from the boundary by the property measurement distance.

[0044] In particular, the content (e.g., percent, wt.%) of the insulator component may be determined by the weight (or volume) of the (total) insulator material, including the liquid component and the insulator component (and any other components, if present). As mentioned, the liquid component of the insulator material may evaporate during the curing and / or drying processing (e.g., by curing, polymerization, UV radiation, sintering, calcination, or any other suitable measure of exposing the insulator material to an energy input) to obtain an insulating coating. Thus, the thickness (i.e., dry thickness) of the remaining insulator material (remaining insulator material, or insulating coating, as described herein) may substantially correspond to the content of the insulator component. Here, changes in the volume of the insulator component, e.g., compression or expansion, that may occur due to the curing and / or drying process may be taken into account or may be ignored.

[0045] Thus, if the content of the insulator components is known, the dry thickness of the insulating coating can be derived from the indicative wet thickness of the insulator material. However, depending on the topology and material of the landing surface onto which the insulator material is applied, the formation of the insulating coating as a result of the curing and / or drying process may not be spatially uniform, i.e., the dry thickness of the insulating coating may vary locally. This may be due, for example, to the fact that the insulator material is a mixture of liquid and insulator components, which may consequently be flowable and / or viscous before undergoing the curing and / or drying process. Also, the substrate and the active material applied thereon may together provide a non-planar landing surface onto which the insulator material is applied. Thus, the insulator components may move or flow to a certain extent after application and therefore may not be uniformly distributed on the applied active material and substrate. Thus, in the prior art, it has been considered difficult to establish a reliable relationship between the thickness of the applied insulator material and the dry thickness of the insulating coating.

[0046] The inventors have discovered that there are specific locations where the thickness of the applied insulator material correlates reliably with the resulting dry thickness of the insulating coating. Such specific locations are referred to as the characterization locations, as described above in this specification. The thickness of the applied insulator material at the characterization locations is referred to as the indicative wet thickness, as described above in this specification. The characterization locations may vary (or may not vary) depending on at least one of the following parameters and characteristics, including: thickness of the applied active material, topology of the applied active material, shape of the edge portion of the applied active material, the insulator material applied on the substrate, and, if applicable, topology of the applied active material, amount of applied insulator material, width (i.e., physical extent in the width direction) of the applied insulator material. Alternatively or additionally, the characterization locations may vary depending on at least one of the following: composition of the insulator material, composition of the active material, and composition of the substrate. Alternatively or additionally, the characteristic measurement distance may vary depending on at least one of the following parameters and characteristics: composition of the insulator material, content of insulator components, curing and / or drying process, and ambient parameters such as temperature, humidity, and pressure. For simplicity of explanation, any of the above mentioned parameters and characteristics may be collectively referred to herein as "positioning factors."

[0047] The property measurement location is offset from the boundary (and edge of the applied active material) by a property measurement distance. In particular, the property measurement location can be on the substrate and / or the property measurement location can be offset from the applied active material. Alternatively, the property measurement location can be on the applied active material on the substrate. This can depend on one or more of the location determining factors mentioned above.

[0048] Since the characteristic measurement distance and thus the characteristic measurement location may each depend on one or more of the location determining factors, the characteristic measurement distance and the characteristic measurement location may first be determined in an empirical manner and then estimated (extrapolated). For example, the content and substance of the insulator components contained in a given insulator material may be determined or known from the preparation of the insulator material. The thickness of the applied insulator material on the substrate may then be determined at different locations relative to the boundary. Here, expressions such as "offset from the boundary" or "relative to the boundary" may indicate that the location or thickness is determined as a function of the distance from the boundary, i.e., at different locations along the width direction. Optionally, the thickness of the applied insulator material may also be determined at different locations along the process direction. Thus, the thickness of the applied insulator material may be determined at an array of locations spanning the edge portion of the applied active material, the boundary, and partial areas of the substrate covered with the insulator material. The dry thickness of the insulator material remaining, particularly after the curing and / or drying process and / or after evaporation of the liquid components of the insulator material, may then be determined at the same locations where the thickness of the applied insulator material was measured. The determined dry thickness of the remaining insulating material is correlated (or compared to or mapped to) the determined thickness of the applied insulating material at each of the different locations. Such an approach may reveal a particular range of measurement distances over which the correlation between the determined thickness of the applied insulating material and the dry thickness of the remaining insulating material is repeatable and predictable.

[0049] As noted above, the active material may be applied onto the substrate to form an edge that is, for example, substantially parallel to the process direction. Thus, determining the thickness of the applied insulator material as a function of distance from the boundary may mean that the thickness is measured at different locations along a width direction perpendicular to the process direction (and the process direction and width direction may each be perpendicular to the thickness direction along which any thicknesses referred to herein are determined). In particular, the substrate having the active material and insulator material applied thereon may be moved in the process direction during the step of determining the thickness of the applied insulator material.

[0050] In a particular example, the battery manufacturing method may (additionally or alternatively) include: measuring the thickness of the insulator material on the substrate at different locations distributed along the process direction and the width direction after applying the active material and the insulator material and before evaporation of X% by weight (X is 0.1-10) of the liquid component of the insulator material. X may be 0.1-10, or 0.1-5, or 0.1-2. For simplicity, the state where the evaporation of the liquid component is X% by weight or less (i.e., the state after X wt.% or less of the liquid component has evaporated) may be referred to herein as the wet state. In this specification, the applied insulator material may refer to the insulator material applied on the substrate while the evaporation of the insulator material is X wt.% or less, unless otherwise specified.

[0051] In certain examples, the battery manufacturing method may (additionally or alternatively) include: determining the thickness of the insulating material remaining at the different locations after evaporation of at least Y% by weight of the liquid component of the insulating material, where Y is between 30 and 99. Y may be between 30 and 99, or between 50 and 99, or between 75 and 99, or between 90 and 99. For simplicity, the state where the evaporation of the liquid component exceeds Y wt.% (i.e., the state after at least Y wt.% of the liquid component has evaporated) may be referred to herein as a dry state. The insulating material remaining after evaporation of Y wt.% of the insulating material may also be referred to as the remaining insulating material or insulating coating, as described herein.

[0052] In certain examples, a battery manufacturing method may (additionally or alternatively) include: identifying (or detecting) a subset of distinct locations, with respect to distance from the boundary, at each distinct location individually, where the correlation between the thickness of the insulator material before evaporation of X% by weight of the liquid component and the dry thickness of the remaining insulator material is reproducible. Any location within the subset of distinct locations identified in the above manner may be referred to herein as a characteristic measurement location, and an individual distance from the boundary may be referred to herein as a characteristic measurement distance.

[0053] As used herein, the term "reproducible" can indicate that the variation can be less than 30%, or less than 25%, or less than 20%, or less than 15%, or less than 10%, or less than 5%, or less than 1%. Correlation can mean that there is a reproducible numerical relationship and / or a reproducible mathematical relationship between the thickness of the applied insulation material (i.e., before evaporation of at least X% by weight of the liquid component) and the dry thickness of the remaining insulation material (i.e., after evaporation of at least Y wt.% of the liquid component).

[0054] Such reproducible numerical relationships may be used to generate a table, such as a database, data array, or look-up table, organized into a table stored in a data store, in which values ​​of the thickness of the applied insulating material and corresponding values ​​of the dry thickness of the remaining insulating material (insulating coating) are related to one another. In this manner, a particular thickness of the applied insulating material may be entered into such a table to obtain the corresponding dry thickness of the remaining insulating material.

[0055] Optionally, fitting, such as extrapolation and / or interpolation, of the reproducible numerical relationships may be performed to extend the numerical relationships to ranges of values ​​that are not physically determined.

[0056] Alternatively or additionally, a regression analysis may be performed to find a continuous (and universal) mathematical relationship between the thickness of the applied insulating material and the thickness of the remaining insulating material. Thus, the mathematical relationship may include an analytical equation having the thickness of the applied insulating material as a variable and the dry thickness of the remaining insulating coating as a function value on the variable. One such mathematical relationship may be a linear function. Alternatively or additionally, the mathematical relationship may be or include one or more of a mathematical function including logarithmic, exponential, polynomial or trigonometric functions. Such a mathematical relationship may allow for an automated calculation of the (resulting) dry thickness of the insulating coating in a reliable manner from the determined thickness of the applied insulating material.

[0057] In some instances, there may be a mathematical relationship between the index wet thickness of the applied insulator material and the dry thickness of the remaining insulator coating. The mathematical relationship may be given by a linear equation as follows:

[0058] t=S d+C

[0059] In the above equations, t is the thickness of the insulating coating (i.e., in the dry state), S is the characteristic slope, d is the index wet thickness, and C is the offset. The parameters S and C may be determined empirically, as described above, from fitting and / or from regression analysis, by a calibration process as described herein. As used herein, a calibration process may refer to a process of finding a location for determining the characteristic measurement location by the characteristic measurement distance from the boundary and accordingly the index wet thickness of the applied insulating material.

[0060] The above equations may make it possible to estimate the thickness t of the remaining insulating coating by means of interpolation and / or extrapolation. The indicative wet thickness d and the dry thickness t may have the same units, for example μm or mm.

[0061] For example, the slope S may be 0.01 to 0.6, or 0.02 to 0.5, or 0.03 to 0.4, or 0.04 to 0.35. For example, the offset C may be -100 μm to +100 μm, or -90 μm to +50 μm, or -80 μm to +30 μm, or -50 μm to +10 μm. In some particular examples, the slope S and / or the offset C may depend on the content (e.g., weight or volume percent) of the insulator component in the insulator material. Alternatively or additionally, the slope S and / or the offset C may be independent of the composition (chemistry) of the insulator component in the insulator material.

[0062] The specific examples as mentioned above can also be considered (referred to as) a calibration process for real-time determination of the dry thickness of an insulating coating. For example, after calibration in the manner described above, the thickness of the applied insulating material can be monitored in real-time.

[0063] Thus, the battery manufacturing method and system as disclosed herein may enable the dry thickness of the insulating coating to be predicted in a reliable manner from a real-time determination of the indicative wet thickness of the applied insulator material. Thus, with respect to the precise location and application of the insulating coating, the quality of the battery product may be increased. At the same time, material, cost, time, and energy requirements may be reduced.

[0064] The battery manufacturing method may include adapting the application of the insulator material as a function of the index wet thickness. As described above, the index wet thickness of the applied insulator material may be used to predict the resulting dry thickness of the insulating coating (remaining insulator material). Thus, the index wet thickness may be utilized to optimize and / or control the application of the insulator material.

[0065] For example, there may be a target dry thickness of the insulating coating for a given battery product. Such target thickness may correspond to a target range of the indicator wet thickness according to a numerical or mathematical relationship as described above. When determining the indicator wet thickness, the indicator wet thickness may be used to predict the dry thickness of the insulating coating in the manner described above. If the indicator wet thickness is outside the target range, the application of the insulating material may be adapted, for example, with respect to application position or application speed, to shift the indicator wet thickness toward the target range. As mentioned, an indicator wet thickness that is within the target range may result in a dry thickness of the insulating coating that is, or is sufficiently close to, the target dry thickness after evaporation and, if applicable, curing and / or drying processes.

[0066] For example, the application position can be adapted by moving the above-mentioned emitter of the insulator material in any of the width, process, and thickness directions. Here, moving the emitter can be moving in one of the width, process, and thickness positive and negative directions. For simplicity, the width direction can be referred to as the left direction and the right direction (e.g., when viewed from a plane depending on the viewing direction), the process direction can be referred to as the forward direction and the backward direction (where the forward direction is the positive direction with respect to the process direction and the backward direction is the opposite direction), and the thickness direction can be referred to as the upward direction (closer to the substrate) and the downward direction (away from the substrate).

[0067] The insulator material may be a mixture of a flowable / viscous insulator component and a liquid component. Also, the landing surface onto which the insulator material is applied may not be flat. Thus, the application of the insulator material, particularly the application of the insulator material via an emitter, may cause a spatially non-uniform distribution of the thickness of the applied insulator material. In particular, the thickness of the applied insulator material may exhibit local maxima. Thus, the application, particularly the application position, may be adapted, for example, to take such effects into account as well. For example, the applied insulator material may exhibit local maxima at positions aligned with the center of the emitter of the insulator material. In case the indicative wet thickness is below a target range, the application position, i.e. the emitter, may be moved such that said local maxima are closer to the property measurement position. Similarly, in case the indicative wet thickness is above a target range, the application position, i.e. the emitter, may be moved such that said local maxima are further away from the property measurement position.

[0068] To accommodate the application of the insulating material, the application speed may be increased or decreased. For example, if the index wet thickness is below a target range, the application speed may be increased. If the index wet thickness is above a target range, the application speed may be decreased.

[0069] Adapting the application, particularly the application speed and / or application location, may be done via a feedback loop that uses the index wet thickness as an input and outputs the application speed and / or application location of the dielectric material. Circuitry and algorithms to subsequently support such feedback loops may be known in the art.

[0070] In some examples, the insulator material can be configured such that when the insulator material is applied, the ratio of liquid component content to insulator component content is 1 to 100, particularly 2 to 50, more particularly 4 to 25, or 5 to 20. If the content ratio is within one of these ranges, a balance between cost, energy consumption, and time requirements of the battery manufacturing method and system and sufficient insulation can be provided.

[0071] In some examples, the thickness of the insulator material (and / or its liquid components) applied onto the substrate may be between 10 μm and 1000 μm, particularly between 20 μm and 500 μm, and more particularly between 50 μm and 250 μm. Optimized values ​​that allow for reduced material, time and energy requirements as well as increased throughput and efficiency of the battery manufacturing methods and systems may be within one of these ranges.

[0072] In some examples, the battery manufacturing method may further include: exposing the (applied) insulator material to an energy input, for example to evaporate the liquid components of the insulator material. In particular, the energy input may be or may include heat and / or radiation, in particular ultraviolet (UV) radiation. Additionally or alternatively, the exposing to the energy input may include exposing the insulator material to an environment (e.g., where the temperature, pressure and / or humidity are adapted to evaporate the liquid components) while the insulator components remain, for example to evaporate the liquid components of the insulator material. Such method steps may be referred to as a curing and / or drying process as described above. During the curing and / or drying process, the content of the liquid components in the applied insulator material may be reduced by Y% by weight, where Y may be 30-99, or 50-99, or 75-99, or 90-99, as discussed above. As a result, an insulating coating may be obtained.

[0073] In some cases, after exposing the insulating material to the energy input, the thickness of the remaining insulating material (and / or insulating components) is between 0.1 μm and 40 μm, particularly between 1 μm and 20 μm, and more particularly between 2 μm and 10 μm. Such a thickness may be referred to as the dry thickness, as discussed above.

[0074] In some examples, the step of determining the thickness of the insulator material may occur before as much as X% of the liquid component of the insulator material evaporates, based on the mass of the applied insulator material, where X may be as described above. In particular, X may be 0.1 to 10, or 0.1 to 5, or 0.1 to 2. For each of these ranges, the lower limit for X may be 0.01, 0.05, 0.2, 0.5, or 1 instead of 0.1.

[0075] In some examples, applying the insulator material can be performed using an emitter located on the substrate. Adapting the applying of the insulator material as a function of the index wet thickness can include repositioning the emitter. The emitter can be as described above and can include any of the corresponding features described herein. For example, repositioning the emitter in at least one of the thickness direction, width direction, and process direction can be as described above.

[0076] In some examples, adapting the application of the insulator material as a function of the index wet thickness may include increasing and / or decreasing the application speed of the insulator material. The application speed may be controlled in a manner as described above. Adapting the application speed, particularly increasing and / or decreasing the application speed, may include any of the corresponding features described herein.

[0077] In some examples, after the step of applying the active material, the active material may form an edge portion on the substrate. The edge portion extends to the boundary and has a concave upper surface on the opposite side of the substrate. After application, the active material may have a bulk portion with an upper surface substantially parallel to the upper surface of the substrate on which the active material is applied. The active material may further have an edge portion formed by not completely covering (the upper surface of) the substrate, as described above. In this way, the edge portion may be formed along (i.e. parallel to and in the vicinity of) the boundary, as described above. As mentioned, the edge portion may form a so-called sliding, where the thickness of the active material does not form a sharp perpendicular surface to the substrate, but smoothly decreases with a rounded upper surface. The formation and shape of the edge portion of the active material may be due to the viscosity and / or flow properties of the active material. Additionally or alternatively, the formation and shape of the edge portion of the active material may be due to a separate application process.

[0078] In some cases, after the step of applying the insulator material, the insulator material may cover at least a portion of the edge portion of the active material and may extend beyond the edge portion onto the substrate. Thus, the insulator material may be applied, for example, to extend over at least a portion of the edge portion of the active material, the boundary, and a portion of the substrate at the boundary.

[0079] In some cases, the substrate, particularly the top surface of the substrate onto which the active material is applied, may be aligned in a plane perpendicular to the thickness direction. The active material may be applied such that boundaries are formed along the process direction perpendicular to the thickness direction as described above.

[0080] In some cases, the insulating material can be applied in stripes on the boundary, the stripes being elongated along the process direction. The stripes can refer to a plan view parallel to the thickness direction (i.e., parallel to the top surface of the substrate, parallel to the width direction and the process direction). In particular, the stripes can be a shape extending in the process direction having a substantially constant width (width direction). In this way, the boundary can be covered in a uniform manner by the insulating coating.

[0081] In some examples, the characteristic measurement distance may be between 0.1 mm and 10 mm, particularly between 0.1 mm and 6 mm, and more particularly between 0.5 mm and 3 mm. In additional examples, the characteristic measurement distance may be at least 0.1 mm and up to 2.5 mm, or up to 2 mm, or up to 1.8 mm, or up to 1.6 mm. The characteristic measurement distance may be determined in the manner described above. As mentioned, a location that is the characteristic measurement distance away from the boundary may be referred to as a characteristic measurement location. The thickness of the insulator material determined at the characteristic measurement location may be referred to as an indicative wet thickness. As mentioned, the characteristic measurement distance and the characteristic measurement location may be determined once for a given insulator material.

[0082] In some cases, the property measurement location may remain the same when different insulator materials are used, for example, by varying the content of the components in the insulator material, particularly the content of the insulator components. Thus, the same property measurement location may be used to determine the indicative wet thickness when the content of the components of the insulator material is changed. Also, the same numerical and / or mathematical relationships as discussed above (e.g., by linear regression, by interpolation and / or extrapolation, etc.) may be used to estimate the dry thickness of the insulating coating.

[0083] Similarly, the characteristic measurement locations may remain constant when the composition of the insulation material is changed, particularly the materials of the insulation components. Thus, the same characteristic measurement locations may be used to determine the indicative wet thickness when different materials are used as the insulation components. Also, the same numerical and / or mathematical relationships as discussed above (e.g., by linear regression, by interpolation and / or extrapolation, etc.) may be used to estimate the dry thickness of the insulating coating.

[0084] In some examples, the method steps of applying active material, applying insulator material, determining the index wet thickness, and adapting the applying insulator material can be performed in a continuous manner while the substrate is moved in the process direction. In this manner, the battery manufacturing method and system can be used in a production line. The throughput and efficiency of battery manufacturing can be increased in this manner.

[0085] The process direction and thickness direction may be as defined herein. In particular, the process direction, thickness direction and width direction may be perpendicular to each other.

[0086] According to one aspect, a battery manufacturing system (i.e., a battery manufacturing system) is provided. As mentioned, the battery manufacturing system may be configured to manufacture batteries, particularly secondary batteries. The battery manufacturing system may include an active material application unit, an insulator material application unit, a measurement unit, and a control unit.

[0087] As noted above, the battery manufacturing systems and battery manufacturing methods disclosed herein may be combined. In particular, the battery manufacturing system may be configured to perform the battery manufacturing method as disclosed herein. Also, since the battery manufacturing system and the battery manufacturing method may be interdependent, the battery manufacturing system may be configured to perform any particular one or combination of features of the battery manufacturing method described herein.

[0088] The active material application unit may be configured to apply the active material. The active material application unit may include an emitter as described above. The active material application unit may include a plurality of emitters each configured to apply the same active material or at least two different active materials.

[0089] The insulator material application unit may be configured to apply the insulator material. The insulator material application unit may include an emitter as described above. The insulator material application unit may include a plurality of emitters each configured to apply the insulator material. In particular, the insulator material application unit, or a portion thereof, may be movable (as described above) to change the application position of the insulator material relative to the substrate or to the active material applied on the substrate. Additionally or alternatively, the insulator material application unit may be controllable (as described above) to change the application speed of the insulator material, for example. The application position and / or application speed changing process may correspond to the step of adapting the step of applying the insulator material of the battery manufacturing method as described herein.

[0090] The measurement unit may be configured to determine an index wet thickness of the insulator material at the property measurement location. The measurement unit may be configured to perform the step of determining an index wet thickness as described herein for the battery manufacturing method. The index wet thickness may include any of the corresponding characteristics described herein.

[0091] In particular, the measurement unit may physically determine (i.e. measure) the index wet thickness. The measurement unit may comprise an optical measurement setup, in particular a reflectance spectrometer as described above. The reflectance spectrometer may use a light source, for example with a spectrum in the (near) infrared near range and / or in the visible range, or in the wavelength range of 400 nm to 1100 nm. The reflectance spectrometer may illuminate the measurement area, for example with a spot size of 2 mm, in particular with a spot size of 1 mm to 1.5 mm. In one example, a portion of the light from the light source is reflected at the incident surface of the target material (i.e. the applied insulator material, the remaining applied material and / or the active material), while another portion of the light is reflected at the interface of the target material and the substrate (also as mentioned herein). Thus, a phase shift between the different reflected portions of the light may be detected, from which the thickness, in particular the index wet thickness, may be derived.

[0092] The control unit may be configured to control the insulator material application unit as a function of the index wet thickness of the insulator material. The control unit may be configured to adapt the application of the insulator material as a function of the index wet thickness in the manner described above. The control unit may be provided as one physical unit. Additionally or alternatively, the control unit may be provided as a distributed system.

[0093] The control unit may include a processor for executing machine-readable instructions. The control unit may include a memory for (temporarily) storing instructions and data. In particular, steps, processes, parameters and variables as disclosed herein may be provided as machine-readable instructions and data. The memory of the control unit may (temporarily) store at least a portion of such instructions and data. The processor of the control unit may be configured to process, execute and / or generate such instructions and data.

[0094] Also, the memory of the control unit may be configured to store a specific relationship between the dry thickness and the indicative wet thickness of the insulating coating. In particular, the memory may be configured to store a numerical and / or mathematical relationship between the dry thickness and the indicative wet thickness of the insulating coating. The numerical and / or mathematical relationship may be as described above.

[0095] The control unit may be configured to receive the index wet thickness from the measurement unit. In certain examples, the control unit may be configured to generate a machine-readable data set including the index wet thickness as a function of time. For such purposes, the measurement unit and / or the control unit may provide a timestamp for each measurement of the index wet thickness. The control unit may be configured to execute instructions that store the index wet thickness in memory.

[0096] The control unit may be configured to adapt the application, in particular the application speed and / or application position, as a function of the index wet thickness in the manner described above. In particular, the control unit may be configured to maintain or change the application position of the insulator material as a function of the index wet thickness. Alternatively or additionally, the control unit may be configured to maintain, increase or decrease the application speed of the insulator material. In this regard, a feedback loop may be used in the manner described above.

[0097] Additionally or alternatively, the control unit may be further configured to perform any of the method steps disclosed herein. The control unit may be further configured to implement any of the features of the battery manufacturing method disclosed herein.

[0098] According to an additional aspect, a battery is provided. The battery may be manufactured by a battery manufacturing method as disclosed herein, which may include any of the corresponding features described herein. Additionally or alternatively, the battery may be manufactured by a battery manufacturing system as disclosed herein, which may include any of the corresponding features described herein. The battery may be or include a secondary battery. However, the claimed subject matter is not limited to secondary batteries, but may be or include a primary battery or any other type of energy storage unit. In certain examples, the battery is configured for use in a mobile device, such as a smartphone or a mobile computer. In other specific examples, the battery may be configured to power an electric vehicle.

[0099] In some examples, the battery may include an insulating coating covering the substrate and the active material applied on the substrate and the interface therebetween. The insulating coating may include any of the corresponding features described herein. In particular, the insulating coating may have a thickness of 0.1 μm to 40 μm, particularly 1 μm to 20 μm, and more particularly 2 μm to 10 μm.

[0100] Such batteries produced by the battery manufacturing methods and / or using the battery manufacturing systems disclosed herein may incorporate an insulating coating that is precisely formed on the interface between the substrate and the active material applied thereon. Thus, the safety of the battery may be increased. Also, the overall cost of producing such batteries may be reduced, since the need for energy, time and materials when producing batteries according to the battery manufacturing methods and / or using the battery manufacturing systems disclosed herein may be reduced. Effect of the Invention

[0101] The battery manufacturing method and battery manufacturing system disclosed herein allow the indicator wet thickness of the insulating material to be determined in real time. The claimed subject matter exploits the fact that there is a correlation between the thickness of the remaining insulating component of the insulating material and the indicator wet thickness of the insulating material. Thus, the thickness of the insulating component of the insulating material remaining on the substrate after evaporation of the liquid component of the insulating material can be estimated from the determined indicator wet thickness. In this manner, the battery manufacturing method and battery manufacturing system disclosed herein allow real-time estimation of the thickness of a solid insulating coating on a substrate. This can also be applied to the interface between the active material and the substrate, as well as the application of a solid insulating coating on the active material applied on the substrate.

[0102] The battery manufacturing method and battery manufacturing system disclosed herein are directed to a method for manufacturing a battery using an insulating material. The accompanying drawings illustrate some specific examples and are intended to aid in understanding the present invention. In this specification and drawings, the same reference number or series of reference numbers may be used in different examples to indicate the same, similar, or similar elements. It should be noted that features shown in the figures may not be to scale, in particular, some features may be illustrated in an enlarged or reduced size manner to emphasize the technical concepts and operating principles of the claimed subject matter, rather than to provide a layout or template for constructing a battery manufacturing system. [Brief description of the drawings]

[0103] [Figure 1] 1 shows a flowchart of a battery manufacturing method according to an example. [Diagram 2] 1 shows a schematic diagram of a battery manufacturing system according to an example. [Diagram 3] 1 shows a schematic plan view of a battery manufacturing process according to an example. [Figure 4] 1 illustrates a schematic plan view of a battery manufacturing system according to an example. [Diagram 5] 1 illustrates a schematic cross-sectional view of a portion of a battery manufacturing system according to an example. [Figure 6] 1 illustrates a schematic exploded view of a battery manufacturing system according to an example. [Figure 7a] 1 shows a schematic side view of a measurement unit according to an example. [Figure 7b] 1 shows a schematic front view of a measurement unit according to an example. [Figure 8a] 1 shows a schematic plan view of a calibration process according to an example. [Figure 8b] 1 illustrates a schematic cross-sectional side view of a calibration process according to an example. [Figure 9] 1 illustrates a schematic cross-sectional view of a portion of a battery manufacturing system according to an example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0104] A method for manufacturing a battery, in particular a secondary battery, is provided. The method may include the following steps, which may be performed in the following order, but are not bound to that particular order:

[0105] applying an active material onto the substrate; For example, applying an insulating material onto the substrate so as to extend over an interface between the active material and the substrate and / or onto the active material, the insulating material including an insulating component and a liquid component; determining an indicative wet thickness of the insulating material at a location on the substrate offset from the boundary by a characteristic measurement distance; Adapting the step of applying the insulator material as a function of the index wet thickness.

[0106] According to one aspect, a battery manufacturing system (i.e., a battery manufacturing system) is provided. As mentioned, the battery manufacturing system may be configured to manufacture batteries, particularly secondary batteries. The battery manufacturing system may include an active material application unit, an insulator material application unit, a measurement unit, and a control unit.

[0107] FIG 1 shows a flow chart of a battery manufacturing method 10. The battery manufacturing method is also referred to herein as a method of manufacturing a battery, where the battery may be or include a secondary battery as mentioned. The battery manufacturing method 10 as shown in FIG 1 may be used to manufacture a battery according to an independent product claim. Also, the battery manufacturing method 10 as shown in FIG 1 may be performed by a battery manufacturing system described herein or examples thereof.

[0108] The battery manufacturing method 10 includes method steps 12, 14, 16, and 18, each of which is shown as a block in FIG. 1. The battery manufacturing method 10 includes, at block 12, applying an active material on a substrate. At block 14, the method 10 includes applying an insulator material on the substrate, for example, to extend over an interface between the active material and the substrate, the insulator material including an insulator component and a liquid component. At block 16, the battery manufacturing method 10 includes determining an index wet thickness of the insulator material at a location on the substrate offset from the interface by a characteristic measurement distance. At block 18, the battery manufacturing method 10 includes adapting the applying of the insulator material as a function of the index wet thickness.

[0109] Thus, the battery manufacturing method 10 may be as described above. Also, the battery manufacturing method 10 as shown in FIG. 1 may additionally include any of the features of the battery manufacturing system as disclosed herein.

[0110] 2 is a schematic diagram of a battery manufacturing system 20 according to an example. The battery manufacturing system 20 includes an active material application unit 22, an insulator material application unit 24, a measurement unit 26, and a control unit 28. The battery manufacturing system 20 may include any of the corresponding features described herein. In particular, the battery manufacturing system 20 may be configured to perform the battery manufacturing method described herein, selectively including any one or a subset of the features of the battery manufacturing method described herein.

[0111] The active material application unit 22 may be configured to apply an active material on a substrate. The active material application unit 22 may include any of the corresponding features described herein. In particular, the active material application unit 22 may be configured to embody any of the features relating to application of an active material on a substrate as disclosed herein. The active material may include any of the corresponding features described herein. In particular, the active material may be prepared to form an electrode, for example, a positive electrode of a secondary battery.

[0112] The insulator material application unit 24 may be configured to apply insulator material onto the substrate and onto the active material applied onto the substrate. The insulator material application unit 24 may include any of the corresponding features described herein. In particular, the insulator material application unit 24 may be configured to embody any of the features relating to application of insulator material onto the substrate as disclosed herein. The insulator material application unit 24 may be configured to apply insulator material onto the substrate, onto the active material applied onto the substrate, and onto the interface therebetween.

[0113] The insulator material may include any of the corresponding features described herein. In particular, the insulator material may include a liquid component and an insulator component. In general, the insulator component may be as described above. In particular, the insulator component of the insulator material may be or include a polymer-based insulator component such as polyvinylidene fluoride (PVDF) and / or a ceramic-based insulator component such as alumina (Al2O3).

[0114] The measurement unit 26 may be configured to determine an indicative wet thickness of the insulator material applied to the substrate at a property measurement location. The measurement unit 26 may include any of the corresponding features described herein. The indicative wet thickness and property measurement location may be as described above.

[0115] The control unit 28 may be configured to control the insulator material application unit 24 as a function of the indicator wet thickness of the insulator material. The control unit 28 may include any of the corresponding features described herein. The application of the insulator material as a function of the indicator wet thickness may be performed as described above. In particular, the control unit 28 may be coupled in signal transmission to the measurement unit 26 to receive the determined indicator wet thickness. The control unit 28 may additionally be coupled in signal transmission to the insulator material application unit 24 to control the insulator material application unit 24 as a function of the indicator wet thickness, in particular by maintaining or varying the application position and / or application speed in the manner described above.

[0116] 3 shows a schematic plan view of a battery manufacturing process. The depiction shown in FIG. 3 may be an intermediate state during the execution of the battery manufacturing method disclosed herein and / or during the operation of the battery manufacturing system disclosed herein. It should be noted that the depictions in the drawings are not to scale.

[0117] The substrate S is moved continuously or intermittently in a process direction P. The substrate may include any of the corresponding features described herein. In particular, the substrate may be or include aluminum metal to provide a current collector for the positive electrode of a secondary battery.

[0118] Active material A is applied onto substrate S at active material application position 22A. Active material A may include any of the corresponding features described herein. In particular, active material A may be an active material including, for example, lithium, for forming a positive electrode of a secondary battery. Active material A may include an insulator component and a liquid component, each of which may include any of the corresponding features described herein. As mentioned, the (major) surface of substrate S onto which active material A is applied may be referred to as the top surface of substrate S.

[0119] As shown in Fig. 3, the active material A is applied, for example, on the substrate (upper surface of the substrate) to cover a partial width (partial area) of the substrate with respect to a width direction W perpendicular to the process direction P. In other words, the active material A is applied, for example, so as not to extend across the entire width of the substrate S, leaving a portion of the substrate S uncovered. In Fig. 3, the right side portion of the substrate S is not covered with the active material A.

[0120] Thus, boundary B is formed along an edge of the applied active material A. In other words, the applied active material A extends to an edge in the width direction W, and such edge forms boundary B between the applied active material A and the substrate S. Boundary B may be provided as described above and may include any of the corresponding features described herein.

[0121] Insulator material N is applied onto substrate S (its upper surface) and onto boundary B at insulator material application position 24N downstream of active material application position 22A relative to process direction P. Insulator material N is also applied onto a portion of active material A applied along boundary B. In other words, applied insulator material N also extends onto applied active material A. Insulator material N and its application may each include any of the corresponding features described herein.

[0122] The substrate S may be stopped in place during the application of the active material A and / or the insulating material N on the substrate S. Alternatively, the substrate S may be moved continuously in the process direction P, during which the application of the active material A and the insulating material N is also performed in a continuous manner.

[0123] 3, width w1 indicates the dimension of the applied insulator material N (and thus the width w1 of the insulating coating) in the width direction W. For example, width w1 can be 1 mm to 20 mm, or 1.5 mm to 15 mm, or 1.8 mm to 10 mm, or 2 mm to 8 mm, or 2.5 mm to 7 mm, or more specifically, 3 mm to 6 mm.

[0124] 3, the width w2 indicates the dimension of the overlap region in the width direction W of the applied active material A and insulating material N (also referred to as an overlay when viewed from a plane perpendicular to the width direction W and the process direction P). For example, the width w2 can be 0.01 mm to 5 mm, or 0.02 to 4 mm, or 0.03 to 3 mm, or 0.04 to 2 mm, or more specifically, 0.05 to 1.5 mm.

[0125] 3, the width w3 indicates the dimension of the insulator material N that directly covers (i.e., has no active material applied therebetween) the substrate S. For example, the width w3 can be 0.5 mm to 20 mm, or 1.5 mm to 15 mm, or 1.8 mm to 10 mm, or 2 mm to 8 mm, or 2.2 mm to 7 mm, or more specifically, 2.5 mm to 6 mm.

[0126] 3, the thickness of the applied insulator material is determined at a property measurement location CP, which is offset from boundary B by a property measurement distance CD. Each of the property measurement location CP and property measurement distance CD may be determined as described above and may include any of the corresponding features described herein.

[0127] In particular, the thickness of the applied insulator material N at the characteristic measurement location CP may be referred to as the index wet thickness as described above. From the determined index wet thickness, the resulting dry thickness of the insulating coating may be estimated in the manner described above. The index wet thickness may be provided as described above and may include any of the corresponding characteristics described herein.

[0128] FIG. 4 illustrates a schematic plan view of an example battery manufacturing system that may correspond to or be a part of the example illustrated in FIG. 2. The battery manufacturing system illustrated in FIG. 4 may include any of the features described herein for the battery manufacturing system. In particular, the battery manufacturing system of FIG. 4 may be configured to perform the battery manufacturing method described herein, optionally including any one or a subset of the features of the battery manufacturing method described herein. Also, the battery manufacturing system of FIG. 4 may correspond to the battery manufacturing process illustrated in FIG. 3.

[0129] The battery manufacturing system of FIG. 4 includes an active material application unit 22 aligned at the active material application position 22A described above. The battery manufacturing system of FIG. 4 also includes an insulator material application unit 24 aligned at the insulator material application position 24N described above. Each of the active material application unit 22 and the insulator material application unit 24 may include any of the corresponding features described herein. In particular, the insulator material application unit 24 may be movable in the process direction (e.g., in the forward and rearward directions, as described above) and / or in the width direction (e.g., leftward and rightward from the orientation as shown in FIG. 4). In this manner, the insulator application position may be changed as a function of the index wet thickness, as described above.

[0130] The battery manufacturing system of Figure 4 further includes a measurement unit 26. The measurement unit 26 is aligned at the characteristic measurement position CP. The measurement unit 26 may include any of the corresponding features described herein. In particular, the measurement unit 26 may be adjustable in width, for example, for a calibration process as described above.

[0131] FIG. 5 illustrates a schematic cross-sectional view of an example battery manufacturing system that may correspond to or be a part of any of the examples illustrated in FIG. 2 and FIG. 4. The battery manufacturing system illustrated in FIG. 5 may include any of the features described herein for the battery manufacturing system. In particular, the battery manufacturing system of FIG. 5 may be configured to perform the battery manufacturing method described herein, optionally including any one or a subset of the features of the battery manufacturing method described herein. Also, the battery manufacturing system of FIG. 5 may correspond to the battery manufacturing process illustrated in FIG. 3.

[0132] The battery manufacturing system of FIG. 5 includes a first coating unit 30, a first drying unit 32, a second coating unit 34, and a second drying unit 36. A substrate (not explicitly shown in FIG. 5) is provided to the first coating unit 30. In the first coating unit 30, the active material and the insulator material are applied onto the substrate in that order in the manner described herein. The first coating unit 30 may include the above-mentioned active material application unit, insulator material application unit, and measurement unit. The battery manufacturing system may include a control unit as described above for controlling the active material application unit, insulator material application unit, and measurement unit in the manner described above.

[0133] The substrate with the applied active material and the applied insulator material is then transported in a process direction P through a first drying unit 32 and subjected to a curing and / or drying process as described above. In particular, the substrate with the applied active material and the applied insulator material may be subjected to an energy input in the first drying unit 32.

[0134] After passing through the first drying unit 32, the substrate may optionally be rotated (flipped) and fed to the second coating unit 34. In the second coating unit 34, the rear surface of the substrate may be coated with an insulator material different from the other active materials, in that order. The rear surface may be the surface of the substrate opposite the top surface of the substrate. The other active materials may be the same as or different active materials as those mentioned above, or may include them. The other insulator materials may be the same as or different insulator materials as those mentioned above, or may include them. The other active materials may be applied onto the substrate (rear surface of the substrate) as described above and in a manner corresponding to the active materials. The other insulator materials may be applied onto the substrate (rear surface of the substrate) and the applied other active materials as described above and in a manner corresponding to the insulator materials.

[0135] The substrate with both the top and rear surfaces coated may then be transported through a second drying unit 36 ​​where the other active materials and other insulator materials applied on the rear surface of the substrate are subjected to a curing and / or drying process as described above. In particular, a substrate having an insulator material different from the other active materials on its rear surface may be subjected to energy input in the manner described above.

[0136] In an alternative example of a battery manufacturing system not explicitly shown, the battery manufacturing system may include one coating unit, such as the first coating unit 30, and one drying unit, such as the drying unit 32.

[0137] FIG. 6 illustrates a schematic exploded view of a battery manufacturing system according to an example. In particular, the battery manufacturing system illustrated in FIG. 6 may correspond to or be a part of any of the examples illustrated in FIG. 2, FIG. 4, and FIG. 5. The battery manufacturing system illustrated in FIG. 6 may include any of the features described herein for the battery manufacturing system. In particular, the battery manufacturing system of FIG. 6 may be configured to perform the battery manufacturing method described herein, selectively including any one or a subset of the features of the battery manufacturing method described herein. Also, the battery manufacturing system of FIG. 6 may be embodied in both the first coating unit 30 and the second coating unit 34 described above with reference to FIG. 5.

[0138] In Fig. 6, the substrate S (which may have applied active material A and applied insulator material N) is moved in a process direction P using a set of conveyor rollers 38. As shown in Fig. 6, the measurement unit 26 is arranged immediately downstream of the insulator material application unit 24 with respect to the process direction P. Specifically, the measurement unit 26 is aligned at a characteristic measurement position CP in Fig. 6. The insulator material application unit 24 and the measurement unit 26 are also coupled to a control unit 28, for example, to enable signal transmission. Each of the insulator material application unit 24, the measurement unit 26, and the control unit 28 may include any of the corresponding features described herein.

[0139] 7a and 7b are schematic side and front views, respectively, of a measuring unit 26 according to an example. The measuring unit 26 shown in Fig. 7a and 7b may be embodied in any of the examples of a battery manufacturing system as disclosed herein, in particular the battery manufacturing system described above with reference to Figs. 2, 4, 5 and 6. Also, the measuring unit shown in Fig. 7a and 7b may be used to perform the battery manufacturing method (corresponding portions thereof) disclosed herein. The measuring unit 26 shown in Fig. 7a and 7b may include any of the corresponding features described herein.

[0140] The measurement unit 26 of Fig. 7a and Fig. 7b includes a light projector 40, a height adjustment screw 42, a width position adjustment screw 44, and a fixing plate 46. The light projector 40 may include or be coupled to (via a waveguide or optical fiber) a light source (not shown). Optionally, the light projector 40 may include a collimator or lens system for focusing light from the light source onto a target plane. The measurement unit may function as a form of reflectance spectrometer as described above. Optionally, the measurement unit may further include an electrically driven shutter for the reflectance spectrometer.

[0141] The fixing plate 46 may be used to fix the measurement unit 26 in an unmovable manner, except for height and width adjustment via the respective screws 42, 44. In particular, the fixing plate 46 may fix the measurement unit 26 to an insulator material application unit of a battery manufacturing system. In this manner, the relative positions of the measurement unit 26 and the insulator material application unit may be fixed.

[0142] Height adjustment screw 42 can be manipulated to adjust the height, i.e., position in the thickness direction T, of light projector 40. In particular, height adjustment screw 42 can be manipulated to adjust the distance between substrate S and light projector 40. In particular, height adjustment screw 42 can be used to focus light from light projector 40, in the manner described above, onto a suitable target plane which may be at different height levels depending on the curvature of the applied active material and the applied insulator material.

[0143] The width adjustment screw 44 can be manipulated to adjust the position of the light projector 40 in the width direction W. Thus, the width adjustment screw can be used to adjust the application position of the insulator material relative to the boundary B as described above. In particular, the width adjustment screw 44 can be used for the calibration process described above.

[0144] 8a and 8b show schematic plan and side cross-sectional views, respectively, of a calibration process according to an example. The calibration process may be performed in the manner described above. The calibration process may include any of the corresponding features described herein.

[0145] As shown in Figures 8a and 8b, the thickness of the applied insulation material can be determined at different locations in the width direction W. In Figures 8a and 8b, the different locations are labelled with measurement points MP. For simplicity, only one of the measurement points MP is labelled with a reference number in Figures 8a and 8b.

[0146] The thickness measurements may be performed in a stop-and-go manner, where the substrate S is intermittently moved in the process direction and stopped for measurements. Alternatively, the thickness measurements may be performed in a continuous manner by a series of measurements at each of the measurement locations MP along the width direction W to obtain a thickness data set as a function of position in the width direction W. Thus, the depiction of the array of measurement locations MP in Figures 8a and 8b is intended to demonstrate that the thickness of the applied insulator material may be measured at any location within the applied area. It is noted that the thickness measurements at the measurement locations MP may be performed before at least X wt.% of the insulator material has evaporated, where X may be as described above.

[0147] As mentioned above, the characteristic measurement positions and characteristic measurement distances, and thus the positions for determining the indicative wet thickness, may be derived from a calibration process in which the thickness of the applied insulating material is determined at different measurement points MP and checked for correlation with the resulting dry thickness of the insulating coating, from which a reproducible numerical and / or mathematical relationship between the indicative wet thickness and the dry thickness may be obtained, on the basis of which the technical effect as mentioned above may be achieved.

[0148] FIG. 9 illustrates a schematic cross-sectional view of a portion of a battery manufacturing system according to an example. The battery manufacturing system illustrated in FIG. 9 may correspond to or be a part of any of the examples illustrated in FIG. 2, FIG. 4, and FIG. 5. The battery manufacturing system illustrated in FIG. 9 may include any of the features described herein for the battery manufacturing system. In particular, the battery manufacturing system of FIG. 9 may be configured to perform the battery manufacturing method described herein, selectively including any one or a subset of the features of the battery manufacturing method described herein. Also, the battery manufacturing system of FIG. 9 may be embodied in both the first coating unit 30 and the second coating unit 34 described above with reference to FIG. 5.

[0149] 9 specifically illustrates the insulator material application unit 24 aligned at the insulator material application position 24N. The insulator material application unit 24 is additionally fluidly coupled to an insulator material supply 48. The insulator material application unit 24 may be movable in the width direction W as a function of the index wet thickness, thereby changing the application position 24N of the insulator material N on the substrate S. The insulator material application unit 24 may be repositioned by a control unit as described above.

[0150] The insulator material application unit 24 may additionally be movable in the thickness direction T. Changing the height of the insulator material application unit 24 may result in a different shape and / or a different spreading of the insulator material N on the substrate S and on the applied active material A. This may be used, for example, to adjust the application of the insulator material N by a control unit.

[0151] Also, the application speed of the insulator material N can be maintained, increased or decreased by correspondingly operating the insulator material supply 48. The insulator material supply 48 can also be controlled by the control unit.

Claims

1. A method for producing a battery, in particular a secondary battery, comprising the steps of: applying an active material onto a substrate; applying an insulator material onto the substrate so as to extend over an interface between the active material and the substrate, the insulator material including an insulator component and a liquid component; determining an indicative wet thickness of the dielectric material at a location on the substrate offset from the boundary by a characteristic measurement distance; and adapting the applying of the insulator material as a function of the indicator wet thickness.

2. 2. The method according to claim 1, wherein the insulating material is configured such that the ratio of the content of the liquid component to the content of the insulating component when the insulating material is applied is 1 to 100, in particular 2 to 50, or 4 to 25, more in particular 5 to 20.

3. The method according to claim 1 or 2, wherein the thickness of the insulating material applied on the substrate is between 10 μm and 1000 μm, in particular between 20 μm and 500 μm, more in particular between 50 μm and 250 μm.

4. 4. The method of claim 1, further comprising exposing the insulator material to energy to vaporize the liquid component.

5. 5. The method of claim 4, wherein after the step of exposing the insulating material to energy, a thickness of the insulating material remaining is between 0.1 μm and 40 μm, in particular between 1 μm and 20 μm, more in particular between 2 μm and 10 μm.

6. 6. The method of claim 1, wherein the step of determining the indicative wet thickness of the insulating material is performed before X % of the liquid component of the insulating material has evaporated, based on the weight of the insulating material applied, where X is between 0.1 and 10.

7. the step of applying the insulator material is performed using an emitter positioned above the substrate; 7. The method of claim 1, wherein adapting the applying of the insulator material as a function of the indicator wet thickness comprises repositioning the emitter.

8. 8. The method of claim 1, wherein adapting the step of applying the insulator material as a function of the indicator wet thickness comprises increasing and / or decreasing an application speed of the insulator material.

9. after the step of applying the active material, the active material forms an edge portion on the substrate, the edge portion extending to the boundary and having a recessed upper surface opposite the substrate; 9. The method of claim 1, wherein after the step of applying the insulator material, the insulator material at least partially covers the edge portions of the active material and extends beyond the edge portions onto the substrate.

10. The substrate is arranged in a plane perpendicular to the thickness direction, the active material is applied such that the boundary is formed along a process direction perpendicular to the thickness direction; 10. The method of claim 1, wherein the insulator material is applied in stripes over the boundary, the stripes being elongated along the process direction.

11. The method according to any one of claims 1 to 10, wherein the characteristic measurement distance is between 0.1 mm and 10 mm, in particular between 0.1 mm and 6 mm, more in particular between 0.5 mm and 3 mm.

12. 12. The method of claim 1, wherein the steps of applying the active material, applying the insulator material, determining the index wet thickness, and adapting the steps of applying the insulator material are performed in a continuous manner while the substrate is moved in a process direction perpendicular to a thickness direction.

13. A system for manufacturing batteries, in particular secondary batteries, comprising: an active material application unit configured to apply an active material onto a substrate; an insulator material application unit configured to apply an insulator material onto the substrate and onto the active material applied onto the substrate; a measurement unit configured to determine an indicative wet thickness of the insulator material applied onto the substrate at a characteristic measurement location; a control unit configured to control the insulation material application unit as a function of the indicative wet thickness of the insulation material.

14. A manufacturing system according to claim 13, configured to carry out the method according to any one of claims 1 to 12.

15. A battery, in particular a secondary battery, manufactured by the method according to any one of claims 1 to 12 and / or by the manufacturing system according to claim 13 or 14, the battery includes a substrate, an active material disposed on the substrate, and an insulating coating covering an interface between the substrate and the active material; The battery, wherein the insulating coating has a thickness of 0.1 μm to 40 μm, in particular between 1 μm and 20 μm, more in particular between 2 μm and 10 μm.

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