System for web-type electrode substrate coating and method for manufacturing electrode webs

Abstract

Systems 210, 310 configured to manufacture an electrode web material by moving in a process direction P and coating a web-type electrode substrate 1 having a web width extending in a lateral direction L perpendicular to the process direction P, include first die coaters 230, 330 including first openings 231, 331 for coating the web-type electrode substrate with battery material, wherein the first openings 231, 331 define a first opening width w extending in the lateral direction L and at least one defining a second opening width a, b extending in the lateral direction L The second die coaters 240, 340, 440 include second openings 241, 341, 342, 441, 442, wherein the widths a, b of the second openings are smaller than the width w of the first openings, and the second openings 241, 341, 342, 441, 442 are offset downstream from the first openings 231, 331 in the process direction P and are also offset in the lateral direction L, and the second openings 241, 341, 342, 441, 442 include free portions located outside the first openings 231, 331 in the lateral direction L.

Description

[Technical Field]

[0001] This disclosure relates to a system for coating web-type electrode substrates, a method for manufacturing electrode webs, and related electrodes and batteries. [Background technology]

[0002] In modern society, as portable devices such as mobile phones, laptops, camcorders, and digital cameras have become widespread, the development of battery technology has become of great significance. Furthermore, rechargeable secondary batteries have become an essential power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) in an effort to reduce air pollution and carbon dioxide emissions from existing fossil fuel-based internal combustion engine vehicles. Therefore, the need for improvement in secondary batteries is increasing.

[0003] Currently available rechargeable batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium-ion batteries. Among these, lithium-ion batteries are attracting attention due to their various beneficial aspects, such as having almost no memory effect compared to nickel-based batteries, being able to be freely charged and discharged, and exhibiting a very low self-discharge rate and high energy density.

[0004] Rechargeable batteries can be classified according to the shape of the battery case into cylindrical batteries, rectangular batteries, and pouch-type batteries, in which the electrode assembly is mounted in a cylindrical metal can. Pouch-type rechargeable batteries generally house an electrode assembly having a structure in which electrodes and a separator membrane are arranged alternately within a pouch-like case made from laminated aluminum sheet.

[0005] Furthermore, secondary batteries can be classified by their structure, in which the positive and negative electrodes are stacked with a separator membrane interposed between them. Generally, there are jelly roll (winding type) structures in which long sheet-like positive electrodes and long sheet-like negative electrodes are wound up with a separator membrane interposed between them, or stacked structures in which numerous positive and negative electrodes cut to a predetermined unit size are sequentially stacked with a separator membrane interposed between them, or similar structures. In recent years, in order to solve the problems that arise with jelly roll type electrode assemblies and stacked type electrode assemblies, stacked / folding type electrode assemblies, which are a combination of jelly roll type electrode assemblies and stacked type electrode assemblies, have been developed.

[0006] Electrodes (preferably electrode sheets), i.e., positive and negative electrodes, are generally formed in a process in which a web-type electrode substrate, such as a metal foil web material, is coated with an active material layer, and then the individual electrode units are separated from the coated web to form an electrode web.

[0007] Die coater systems are commonly used to coat web-type electrode substrates to produce battery electrodes. Some die coater systems are described in Patent Documents 1, 2, 3, and 4. In such die coater systems, a die block assembly has an opening toward a web-type electrode substrate guided by a roll located in front of the die block assembly. The axis of rotation of the roll is aligned with the opening in the die block assembly. The active material is coated onto the web-type electrode substrate by supplying an active material slurry through the die block assembly. The active material slurry may differ from the active material in that the slurry further contains at least one solvent or similar. The die block assembly may include two or more die blocks that are rigidly coupled to each other. Channels can be formed as slots between two die blocks that engage with each other. To supply the active material slurry, at least one of the die blocks in the assembly is provided with a manifold, one end of which is connected to a supply line and the other end of which is connected to a channel extending to the opening.

[0008] To achieve maximum output, it is preferable to coat the web-type electrode substrate with an active material layer of a certain thickness, width, and height. The thickness profile and inclination angle at the side edges of the active material layer on the electrode substrate are considered to be particularly related.

[0009] To control the amount of active material slurry and uniformly coat the active material layer onto the web-type electrode substrate, various forms of shims are generally placed between two die blocks. The shims are positioned to control the amount and thickness profile of the active material slurry discharged from the slot between the two die blocks. Various shim designs are used to achieve the desired thickness profile of the active material layer.

[0010] However, existing die block assemblies are known to produce coatings with irregularly shaped or undesirable sides or edges. In particular, existing assemblies have proven unsuitable for ensuring the sustained quality of electrode coatings when processing conditions fluctuate or environmental impacts on the die or slurry change.

[0011] In such cases, the resulting electrodes may be of lower quality, which can lead to a decrease in battery life, capacity, voltage, energy density, and power level. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] Korean Published Patent Publication No. 10-2022-0027024 [Patent Document 2] Korean Published Patent No. 10-2022-0094459 [Patent Document 3] Korean Registered Patent Publication No. 10-1750599 [Patent Document 4] Korean Published Patent Publication No. 10-2020-037662 [Overview of the project] [Problems that the invention aims to solve]

[0013] The purpose of this disclosure is to overcome the shortcomings of the prior art, in particular, to provide a system for coating web-type electrode substrates with battery material, a method for manufacturing electrodes, and electrodes that enable rapid, reliable, and / or efficient production, preferably of the highest quality.

[0014] However, the problems to be solved by the embodiments of this disclosure are not limited to the problems described above and can be broadly expanded within the scope of the technical idea contained herein. [Means for solving the problem]

[0015] One or more problems known in the prior art are solved by the subject matter of the independent claim. Specific embodiments are provided by the features of the dependent claim.

[0016] Some of the features and operations of the die coater and the die coater and / or wheel described above may also be adopted in the claimed subject matter and may not be repeated below for the sake of brevity of explanation.

[0017] Therefore, a system for coating web-type electrode substrates and a method for manufacturing electrodes are provided.

[0018] This system is configured to coat a web-type electrode substrate that moves in a process direction to manufacture electrode web material. Coating the web-type electrode substrate can refer to the process by which battery material is discharged from the system onto the web-type electrode substrate to form a battery material layer. Detailed aspects of the coating process are described below in the following section of the electrode manufacturing method.

[0019] According to the present disclosure, the system includes a first die cutter including a first opening for applying a (first) battery material to a web-type electrode substrate. The first opening defines a width (first opening width) extending in the side direction. In some preferred cases, the first die cutter may include at least two, at least three, at least four or more first openings.

[0020] The system according to the present disclosure also includes a second die cutter. The second die cutter can be configured to apply a (first) battery material to the web-type electrode substrate. The second die cutter can be separately arranged from the first die cutter. For example, the second die cutter can be located on at least one side edge side of the first die cutter. Preferably, a pair of second die cutters can be located on two side edges of the first die cutter. Particularly in the case of a system having a plurality of first openings in one or more first die cutters, the pair of second die cutters can be located on two side edges of each first opening. Therefore, the active material layer formed on the side edge of the web-type electrode substrate extending in the side direction can be precisely and individually adjusted.

[0021] [[ID=?]] The second die cutter includes at least one second opening (second discharge port) for discharging the (first) battery material. The second opening can be configured to apply the (first) battery material to the web-type electrode substrate. The second opening defines a second opening width extending in the side direction. The second opening width is smaller than the first opening width.

[0022] In the system according to the present disclosure, the second opening is offset from the first opening downstream in the process direction. Also, the second opening is offset from the first opening in the side direction, and the second opening includes a free portion disposed outside the first opening in the side direction. The free portion of the second opening is arranged to apply the (first) battery material, particularly to the web-type electrode substrate. The free portion defines a free width extending in the side direction.

[0023] By implementing a first die coater and a second die coater, it becomes possible to control the pressure difference between the central and lateral portions (side edges) of the active material slurry applied to the electrode substrate. The slurry applied through the first die coater can be supplied at a large flow rate, while the slurry applied through the second die coater, which is laterally adjacent to the first die coater, can be finely adjusted to determine the flow rate discharged from the coating edge region. By controlling the active material or other battery material applied to the electrode substrate through the second die coater, the height and shape of the active material coating at the side edges of the coating can be precisely adjusted.

[0024] In particular, using a second die coater having a second opening with a free portion located outside the side of the first opening allows for fine adjustment of the side edges of the coated active material layer. By adjusting the flow rate through the second opening and its free portion, the coating process can be quickly adapted to changing manufacturing conditions and other factors. The free portion allows for independent control of the coating on the side edges, enabling precise adjustment of their size and shape.

[0025] <Web-type electrode substrate> A web-type electrode substrate may contain or be composed of an electrically conductive material. In particular, a web-type electrode substrate may be composed of or contain a metal or metal alloy, for example, aluminum or copper, or may contain aluminum or copper.

[0026] A web-type electrode substrate may have a web length, which can be defined as the dimension of the web-type electrode substrate in the process direction. A web-type electrode substrate may have a web width, which can be defined as the dimension of the web-type electrode substrate extending in the lateral direction perpendicular to the process direction. A web-type electrode substrate may have a web thickness, which can be defined as the dimension of the web-type electrode substrate extending in the thickness direction perpendicular to the process direction and the lateral direction.

[0027] Electrode web materials manufactured by coating a web-type electrode substrate with battery material can be further processed to function as electrode units or similar entities, particularly positive electrode units or negative electrode units. In particular, electrode units produced by the above-described system can be formed into jelly-roll type electrode assemblies, laminated electrode assemblies, or laminated / folding type electrode assemblies.

[0028] The term "web material" should be understood as a general term referring to films, sheets, foils, meshes, porous materials (e.g., sieves, foams, nonwovens) or similar web-type materials. A web material has a web length that is substantially larger than its web width, and the web width is substantially larger than its web thickness. For example, the web thickness of a web-type electrode substrate to be processed can be in the range of 1 μm to 100 μm, preferably 3 μm to 30 μm, and more preferably 5 μm to 15 μm. For example, the web width of a web-type electrode substrate to be processed can be in the range of 1 mm to 5000 mm, preferably 10 mm to 1000 mm, and more preferably 50 mm to 500 mm. For example, the web length of a web-type electrode substrate to be processed can be in the range of 10 m to 100 km, preferably 100 m to 50 km, and more preferably 500 m to 25 km. During processing, particularly during the coating step, the typical speed of movement of the web material can be as high as approximately 100 m / min.

[0029] <First Die Coater> The first opening may have a first cross-sectional area configured to face the web-type electrode substrate. The first opening may generally have a rectangular cross-section. The first opening preferably extends in the process direction and the lateral direction. The extension of the first opening in the lateral direction is preferably the first dimension of the first opening. It should be clear that the extension of the first opening in the lateral direction defines the width of the first opening (first opening width). The extension of the first opening in the process direction can be considered the length of the first opening. The length of the first opening is preferably less than its width. The lateral or first extension of the first opening is preferably greater than the extension of the first opening in the second direction, particularly at least 5 times, preferably at least 10 times, and more preferably at least 100 times greater. The first opening may have a slot-like shape. The rectangular opening defined by the first opening is substantially wider than its length. The first (lateral) extension or width of the first opening is preferably at least 10 mm, particularly at least 100 mm or at least 200 mm, preferably at least 400 mm, and not exceeding 2000 mm, particularly not exceeding 1000 mm. The first opening preferably defines a first opening width that extends in the lateral direction. The first opening width is preferably in the range of, for example, 50 mm to 800 mm. Preferably, the first opening width can be in the range of 50 mm to 600 mm. More preferably, the first opening width may be 505 mm or less. The second extension (in the process direction) or length of the first opening is preferably less than 1 mm, preferably less than 100 μm, and greater than 1 μm, preferably greater than 10 μm.

[0030] The first opening (first discharge port) defines the discharge direction. The discharge direction can be specified as a third direction. The discharge direction preferably corresponds to the thickness direction. The discharge direction corresponds to the direction in which the active material slurry passes through the first opening when it exits the first die coater. The discharge direction can correspond to a direction perpendicular to the plane defined by the first and second directions in which the cross-section of the first opening extends. In other words, the discharge direction is preferably perpendicular to the plane in which the cross-sectional area of ​​the first opening is oriented.

[0031] The first die coater can be positioned such that the substrate is located in front of the first opening at a certain coating distance. The coating distance preferably extends between the first opening and the foil in the discharge direction or a third direction. The coating distance between the substrate and the first opening can be configured to correspond to a desired active material layer thickness. With respect to the lateral direction, the substrate can be positioned parallel to the first opening. Parallel positioning of the substrate (foil) to the first opening in the lateral direction can be achieved, for example, by guiding the substrate on a roll of a certain diameter having a rotation axis positioned in the lateral direction.

[0032] <Second Die Coater> The second opening may have a second cross-sectional area configured to face the web-type electrode substrate. The second opening may generally have a rectangular cross-section. The second opening preferably extends in the process direction and the lateral direction. The extension of the second opening in the lateral direction is preferably the first dimension of the second opening. It should be clear that the extension of the second opening in the lateral direction defines the width of the second opening (second opening width). The extension of the second opening in the process direction can be considered the length of the second opening. The length of the second opening is preferably less than its width. The lateral or first extension of the second opening is preferably greater than the extension of the second opening in the second direction, particularly at least 1.5 times, preferably at least 2 or 5 times, and more preferably at least 10 times greater. The second opening may have a slot-like shape. The rectangular opening defined by the second opening is preferably at least as wide as length. The first (lateral) extension or width of the second opening is preferably at least 0.2 mm, particularly at least 0.3 mm or at least 0.5 mm, preferably at least 1 mm, and not exceeding 30 mm, particularly not exceeding 15 mm, preferably not exceeding 10 mm, and more preferably not exceeding 5 mm or 2 mm. The second opening preferably defines a second opening width that extends in the lateral direction. The second opening width is preferably in the range of, for example, 0.5 mm to 50 mm. Preferably, the second opening width can be in the range of 1 mm to 25 mm. More preferably, the second opening width may be 15 mm, 10 mm or less, or 5 mm or less. The second extension (in the process direction) or length of the second opening is preferably less than 1 mm, preferably less than 100 μm, and more than 1 μm, preferably more than 10 μm.

[0033] The second opening (second outlet) defines a second discharge direction. The second discharge direction is preferably parallel to the discharge direction of the first opening. The discharge direction preferably corresponds to the thickness direction. The second discharge direction corresponds to the direction in which the active material slurry passes through the second opening as it exits the second die coater. The second discharge direction can be perpendicular to the plane defined by the first and second directions, from which the cross-section of the second opening extends. In other words, the second discharge direction is preferably perpendicular to the plane from which the cross-sectional area of ​​the second opening is oriented.

[0034] The second die coater can be configured such that the substrate is positioned in front of the second opening at a constant second coating distance. The second coating distance preferably extends between the second opening and the substrate in the second discharge direction. The coating distance between the substrate and the second opening can be configured to correspond to a desired layer thickness. With respect to the lateral direction, the substrate can be positioned parallel to the second opening.

[0035] <Battery Materials> The (first) battery material discharged from the first opening of the first die coater may be an active electrode material (abbreviated as: active material). For example, an electrode configured to act as a negative electrode may be provided with an active material layer configured to accommodate and / or store ions, preferably in a releasable manner. The active material, in particular the active material for the negative electrode, may include graphite as a first component. An electrode configured to act as a positive electrode may include an active material configured to release ions. The active material, in particular the active material for the positive electrode, may include or be composed of a metal oxide such as lithium oxide. The active material may include, for example, LCO (LiCoO2), NCM (Li(NiCoMn)O2), NCA (Li(NiCoAl)O2), LMO (LiMn2O) and / or LFP (LiFePO4), or be composed of them. The active material may include conductive additives, binders, fillers and other components (active material mixtures). The active positive electrode material may be configured to be refillable. The process of releasing ions from the positive electrode active material and receiving them with the negative electrode active material can be called discharge. The process of releasing ions from the negative electrode active material and replenishing the positive electrode active material with ions can generally be called charging or recharging. The active material used in the electrodes of a battery is considered essential for determining the battery's characteristics, such as capacity, voltage, and memory effect.

[0036] The positive electrode active material coated on the positive electrode unit and the negative electrode active material coated on the negative electrode unit may, without limitation, include all active materials known in the art related to this disclosure.

[0037] For example, the positive electrode active material is A[A x M y ]O 2+zIt can contain an alkali metal compound represented by the formula (A contains at least one of Li, Na or K; M contains at least one selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru and Cr; x≧0, 1≦x + y≦2, 0.1≦z≦2. The stoichiometric coefficients x, y and z are selected to keep the compound electrically neutral).

[0038] In other examples, the positive electrode active material can be an alkali metal compound xLiM1O2(1 - x)Li2M2O3 (M1 contains at least one element having an average trivalent oxidation state; M2 contains at least one element having an average tetravalent oxidation state; 0≦x≦1) disclosed in U.S. Patent No. 6,677,082 and U.S. Patent No. 6,680,143.

[0039] In another example, the positive electrode active material is Li a M1 x Fe 1-x [[ID=#14]]M2 y P 1-y M3 z O 4-z A lithium metal phosphate represented by the formula (M1 contains at least one selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg and Al; M2 contains at least one selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V and S; M3 contains a halogen group element optionally containing F; 0 < a≦2, 0≦x≦1, 0≦y < 1, 0≦z < 1. The stoichiometric coefficients a, x, y and z are selected to keep the compound electrically neutral) or Li3M2(PO4)3 [M contains at least one selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg and Al] can be used.

[0040] For example, the negative electrode active material can include carbon materials, lithium metal or lithium metal compounds, silicon or silicon compounds, tin or tin compounds. Metal oxides with a potential of less than 2V, such as TiO2 and SnO2, can be used as negative electrode active materials. The carbon material can include low-crystalline carbon and high-crystalline carbon.

[0041] In some embodiments, the second die coater can be configured to move independently in the thickness direction. By moving the second die coater in the thickness direction, the amount of battery material coated onto the web-type electrode substrate can be controlled. The second die coater can be configured so that the second opening moves toward and away from the web-type electrode substrate by at least 1 μm, particularly at least 3 μm, more particularly at least 5 μm, and / or up to 50 μm, particularly up to 25 μm, and more particularly up to 10 μm from its stationary position. For example, as the second die coater moves toward or away from the web-type electrode substrate in the thickness direction, the amount of coated battery material may increase or decrease. Thus, the side edges of the active material layer can be precisely and individually controlled. As a result, the efficiency, performance, and lifespan of the battery are increased.

[0042] As an addition or alternative, the first die coater may be configured to be movable in the thickness direction. The first die coater may be configured so that the first opening can move from a stationary position toward and / or toward the web electrode substrate. By moving the first die coater in the thickness direction, the amount of (first) battery material coated on the web electrode substrate per unit area can be controlled. For example, as the first die coater moves toward or away from the web electrode substrate in the thickness direction, the amount of battery material coated per unit area may increase or decrease. Thus, the overall thickness of the active material layer formed on the web electrode substrate may increase or decrease.

[0043] According to some embodiments, the second opening width may be 10% or less of the first opening width. Preferably, the second opening width may be less than 5% of the first opening width. More preferably, the second opening width may be less than 2.5% or 1% of the first opening width. For example, the second opening width may be 20 mm or 15 mm or less. Preferably, the second opening width may be 10 mm or less. More preferably, the second opening width may be 5 mm or less.

[0044] In some embodiments of the system according to this disclosure, the second opening may include an overlapping portion that at least partially overlaps the first opening in the lateral direction. The overlapping portion may define an overlap width extending in the lateral direction. The overlap width may be smaller than the free width. For example, the free width may be 50% or more of the second opening width. Preferably, the free width may be 60% or more of the second opening width. More preferably, the free width may be 70% or more of the second opening width.

[0045] The second die coater may include an additional third opening (third discharge port). The third opening may be configured to discharge a second battery material. For example, the second battery material may be an active material. In other examples, the third opening may be a dielectric material. For example, the dielectric material may be PVDF, CMC, SBR, or similar. However, the dielectric material is not limited thereto. The third opening may be positioned parallel to the second opening in the lateral direction, in which case the third opening is offset from the first opening more than the second opening in the process direction.

[0046] The third opening can be offset from the first opening by the same lateral offset as the second opening. If the second and third openings are offset similarly from the first opening by the same distance, it is preferable to apply this to the production of the negative electrode. For example, both the second and third openings can discharge active material. In this case, the second battery material discharged from the third opening may be the active material and may have a different adhesive strength than, for example, the active material discharged from the second opening. The adhesive strength of the active material can generally be increased or decreased by controlling the amount and / or type of binder mixed with the active material. As a result, a particularly stable structure of the electrode web can be achieved, and a precise thickness profile can be obtained even at the lateral edges of the electrode web. This allows for maximizing the battery capacity.

[0047] Optionally, the third opening can be offset outward in the lateral direction from the first opening compared to the second opening. More specifically, the third opening can be located adjacent to the second opening. The lateral offset of the third opening can correspond to the outer edge of the side of the second opening. Preferably, the third opening can at least partially overlap the second opening in the lateral direction. The third opening can overlap the second opening by, for example, up to 3 mm, preferably up to 2 mm, in the lateral direction. More preferably, the third opening can overlap the second opening by up to 1 mm in the lateral direction. If the third opening is offset outward in the lateral direction from the first opening compared to the second opening, it is more preferable to apply this to manufacture a positive electrode. In this case, the second battery material may include or constitute a dielectric material.

[0048] This disclosure also relates to a method for manufacturing an electrode web. The method for manufacturing an electrode web may preferably utilize a system for coating the web-type electrode substrate described above. The system for coating the web-type electrode substrate described above is preferably configured to operate in accordance with the method for manufacturing an electrode web. The method for manufacturing an electrode web may include a variety of steps.

[0049] The method of this disclosure includes the step of providing a web-type electrode substrate. The web-type electrode substrate can have a defined web width extending in the lateral direction. The lateral direction is parallel to the planar surface of the web-type electrode substrate and may be perpendicular to the process direction in which the web-type electrode substrate moves. The web width can be configured in the range of, for example, 50 mm to 800 mm. Preferably, the web width can be configured in the range of 50 mm to 650 mm. More preferably, the web width can be configured to be 550 mm or less.

[0050] The method according to this disclosure further includes the step of moving a web-type electrode substrate in the process direction. Here, moving the web-type electrode substrate can mean a continuous movement, such as transporting, transferring, and / or transmitting the web-type electrode substrate from one position to another. A transfer device can be configured to move the web-type electrode substrate. The transfer device may include, for example, a conveyor, such as a belt conveyor, a roller conveyor, a chain conveyor, and / or a combination thereof.

[0051] According to this disclosure, the method also further includes the step of applying an amount of (first) battery material to a first surface region on a first side surface of a web-type electrode substrate to form a first coating area. The (first) battery material may be, for example, an active material. For example, a web-type electrode substrate, which is a foil or a sheet, includes two planes extending in the lateral direction and the process direction. The first side surface of the web-type electrode substrate may be the side on which one of the two planes faces a first opening of the system. The web-type electrode substrate may also further include a first surface region on the first side surface. The first surface region may be defined as a region that includes the center point of one planar surface on the first side surface of the web-type electrode substrate and extends continuously in the process direction and the lateral direction. This center point may be defined as the point on the first side surface where two diagonals of one surface intersect. The first surface region may also be defined as a region on which the battery material discharged from the first opening of the coating system described above is coated. The first surface region may be formed to include a first width in the lateral direction. For example, the first width may be the same as or less than the web width of the web-type electrode substrate. Preferably, the first width may be 550 mm or 510 mm or less. More preferably, the first width may be 505 mm or less. For example, the first width may be 504 mm. The first coated portion may be part of the (first) battery material coated portion. The first coated portion is formed by applying an amount of (first) battery material to a first surface area on the first side surface of the web-type electrode substrate. The amount of (first) battery material may be the amount discharged from the first opening of the coating system. In other words, the first coated portion can be formed by applying the (first) battery material discharged from the first opening of the coating system. The first coated portion is formed to include a contact surface that contacts the web-type electrode substrate and an upper surface opposite to the contact surface.

[0052] In the electrode manufacturing method of the present disclosure, the first coated portion is formed such that at least one side edge of the coating includes an inclined edge portion that slopes from the upper surface toward the web-type electrode substrate. The inclined edge portion includes an inclination width that extends in the lateral direction. The inclination width is 10%, 5%, or preferably 1% or less of the first width.

[0053] The electrode manufacturing method of the present disclosure further includes the step of applying an additional amount of (first) battery material to a second surface region on a first side surface of a web-type electrode substrate. The second surface region may be formed in a region offset from the first surface region in the lateral direction. The second surface region may be formed laterally adjacent to the first surface region and extend in the process direction. In the manufacturing method of the present disclosure, the step of applying an additional amount of (first) battery material to a second surface region on a first side surface of a web-type electrode substrate offset from the first surface region in the lateral direction is also performed to form a cover coating on a first surface region that extends at least partially over the first coating. The cover coating is formed on a portion of the upper surface of the first coating. More specifically, the cover coating may be formed on at least one side edge of the upper surface of the first coating. For example, the cover coating may be formed to completely cover an inclined edge of the first coating. In other examples, the cover coating may be formed to at least partially cover an inclined edge of the first coating. The thickness of the second coating area can be defined in a thickness direction perpendicular to the process direction and the lateral direction. For example, the thickness of the second coating area may be the same as or greater than the thickness of the first coating area. It may be preferable to use a second coater to form the second coating area. By forming the second coating area, the active material layer formed on the side edge of the web-type electrode substrate extending in the lateral direction can be precisely controlled. The coating of the second coating area, which is laterally adjacent to the first coating area, can be finely adjusted to determine the flow rate discharged from the edge region of the coating. By controlling the active material or other battery material coated on the electrode substrate in the second coating area at the edge of the first coating area, the height and shape of the active material coating at the side edge of the coating can be precisely controlled.

[0054] In a preferred embodiment of the manufacturing method of the present disclosure, the second surface region may have a first width in the lateral direction. For example, the first width may be 10% or less of the first surface region. Preferably, the first width may be 5% or less of the first surface region. More preferably, the first width may be 1% or less of the first surface region. For example, the first width may be in the range of 0.1 mm to 5 mm. Preferably, the first width may be in the range of 0.1 mm to 4 mm, 0.1 mm to 3 mm, 0.1 mm to 2 mm, or more preferably 0.1 mm to 1 mm.

[0055] A second coated area can be directly formed on the web-type electrode substrate by applying the (first) battery material at an offset position on the web-type electrode substrate. The second coated area may be part of the (first) battery material coated area formed in a second surface area laterally adjacent to the first surface area. The second coated area may have a second width in the lateral direction. The second width may be the same as or greater than the first width.

[0056] The second coating portion can be formed to have a contact surface that contacts the web-type electrode substrate and an upper surface opposite to the contact surface. Preferably, the second coating portion can be formed to have an inclined edge. The inclined edge of the second coating portion can be formed on at least one side edge that slopes from the upper surface toward the web-type electrode substrate. The inclined edge of the second coating portion can have a defined inclination width extending in the lateral direction. The inclination width may be, for example, in the range of 0.1 mm to 4 mm, 0.1 mm to 3 mm, 0.1 mm to 2 mm, or preferably 0.1 mm to 1 mm.

[0057] The cover coating area can be formed to be 50% or less of the second coating area, or in other words, the second coating area is 50% or more of the cover coating area.

[0058] The second coating area and the cover coating area can be formed by applying an additional amount of (first) battery material. The additional amount of (first) battery material can be discharged from the second opening of the coating system. The additional amount may be less than the amount of (first) battery material applied by the first opening of the coating system.

[0059] Additionally, this method may further include the step of coating a second battery material onto a third surface region on a first side surface of a web-type electrode substrate. The third surface region may be an area offset from the second surface region on the opposite side of the first surface region. The third surface region may be laterally adjacent to the second surface region and extend in the process direction. By coating the second battery material additionally at the offset location on the web-type electrode substrate, the second battery material can be coated directly onto the web-type electrode substrate. The second battery material can be coated laterally adjacent to the second coating area. Alternatively, the second battery material can be coated at least partially on the second surface region. For example, the second battery material can be coated at least partially on the upper surface of the second coating area. The second battery material may be material discharged from a third opening in the coating system.

[0060] For example, the second battery material may include or consist of the first battery material. In other examples, the second battery material may be different from the first battery material. For example, the second battery material may include or consist of a dielectric material.

[0061] The electrode webs manufactured by the method described above, preferably positive electrode webs or negative electrode webs, can be processed to be cut into electrode sheets (electrode units), i.e., positive electrode sheets and / or negative electrode sheets, preferably into predetermined unit sizes. Preferably, the positive electrode and / or negative electrode sheets produced by the electrode manufacturing method described above are sequentially laminated with a separator film interposed between the positive electrode sheet and the negative electrode sheet. Depending on the desired battery type, e.g., pouch type or jelly roll type, the laminated electrode sheets can be wound or folded as additional material to achieve the desired electrode configuration. The wound or folded electrode sheets can be inserted into a suitable battery container, e.g., a pouch, can, or other suitable container, depending on the battery type.

[0062] This disclosure also relates to electrodes (preferably electrode webs or electrode sheets), particularly electrodes for secondary batteries. Electrodes can be produced according to the methods described above and / or using the systems described above.

[0063] The electrode includes an electrode substrate. The electrode substrate may be a web-type material (abbreviated as web material), such as a film, sheet, or foil. The electrode substrate may contain or be composed of an electrically conductive material. In particular, the electrode substrate may be composed of or contain a metal or a metal alloy, for example, aluminum or copper, or aluminum or copper.

[0064] The electrode according to this disclosure includes a battery material coated portion on an electrode substrate. The battery material coated portion includes a battery material formed on the electrode substrate. The battery material may be an active material. The width of the battery material coated portion can be defined in the lateral direction. The width of the battery material coated portion can be in the range of 50 mm to 1000 mm, 50 mm to 800 mm, 50 mm to 600 mm, or 50 mm to 500 mm. The thickness of the battery material coated portion can be defined in the thickness direction. The thickness of the battery material coated portion can be in the range of 20 μm to 250 μm, 20 μm to 200 μm, 20 μm to 150 μm, or 20 μm to 100 μm. The battery material coated portion includes a contact surface that contacts the electrode substrate and an upper surface opposite to the contact surface.

[0065] According to this disclosure, the battery material coating portion also further includes an inclined edge portion on at least one side edge of the coating. The inclined edge portion is the portion that slopes from the top surface toward the electrode substrate. The inclined edge portion defines an inclination width that extends in the lateral direction. The inclination width according to this disclosure is 1% or less of the width of the battery material coating portion. In addition, the inclination width may be at least 0.01%, particularly at least 0.1%, of the width of the battery material coating portion in some embodiments. The inclined edge portion may extend in the lateral direction from one side edge toward the other side edge in the range of 0.1 mm to 8 mm, 0.1 mm to 6 mm, 0.1 mm to 5 mm, 0.1 mm to 4 mm, or 0.1 mm to 3 mm. Preferably, the inclined edge portion may extend in the lateral direction from one side edge toward the other side edge in the range of 0.1 mm to 2 mm, more preferably 0.1 mm to 1 mm.

[0066] Additionally, the electrode may include a second material coating on the electrode substrate. The second material coating portion may be a layer containing the second material, such as a dielectric material. The second material coating portion may be formed on the electrode substrate adjacent to the side edge of the battery material coating portion.

[0067] As an addition or alternative, the second material coating can partially cover the upper surface of the battery material coating. For example, the second material coating can be formed on at least one side edge or opposite edges on both sides of the upper surface of the battery material coating. The electrode including the second material coating may preferably be the positive electrode.

[0068] This disclosure also relates to a battery including at least one of the electrodes disclosed above. [Effects of the Invention]

[0069] According to the embodiment, an active material coating with a significantly improved shape can be applied to a substrate such as foil for forming electrodes, particularly at the side edges of the coating.

[0070] The effects of this disclosure are not limited to those described above, and any additional effects not mentioned above can be clearly understood by those skilled in the art from the descriptions of the appended claims. [Brief explanation of the drawing]

[0071] [Figure 1] This is a device for processing metal foil web material into electrode webs. [Figure 2A] This is a schematic diagram of an existing die coater. [Figure 2B] Figure 2A is a schematic diagram of the coating process using a die coater. [Figure 2C] Figure 2A is a schematic cross-sectional view of an electrode manufactured using the die coater. [Figure 3A] This is a schematic diagram of the die coater system as disclosed herein. [Figure 3B] Figure 3A is a schematic illustration of the coating process according to this disclosure using the system shown. [Figure 3C] Figure 3A is a schematic cross-sectional view of the electrode according to this disclosure, manufactured using the die coater shown. [Figure 4A] This is a schematic diagram of another die coater system as disclosed herein. [Figure 4B] Figure 4A is a schematic diagram of the second die coater for the die coater system. [Figure 5] This is a schematic diagram of another second die coater. [Modes for carrying out the invention]

[0072] Therefore, a system for coating web-type electrode substrates and a method for manufacturing electrodes are provided.

[0073] This system is configured to coat a web-type electrode substrate that moves in a process direction to manufacture electrode web material. Coating the web-type electrode substrate can refer to the process by which battery material is discharged from the system onto the web-type electrode substrate to form a battery material layer. Detailed aspects of the coating process are described below in the following section of the electrode manufacturing method.

[0074] According to this disclosure, the system includes a first die coater having a first opening for coating a (first) battery material onto a web-type electrode substrate. The first opening defines a width (first opening width) extending in the lateral direction. It may be preferable that the first die coater has at least two, at least three, or at least four or more first openings.

[0075] The system according to this disclosure also includes a second die coater. The second die coater may be configured to coat a (first) battery material onto a web-type electrode substrate. The second die coater may be positioned separately from the first die coater. For example, the second die coater may be located on at least one side edge of the first die coater. Preferably, a pair of second die coaters may be located on two side edges of the first die coater. Particularly in systems where one or more first die coaters have multiple first openings, a pair of second die coaters may be located on two side edges of each first opening. Thus, the active material layer formed on the side edges of a web-type electrode substrate extending in the lateral direction can be precisely and individually controlled.

[0076] The second die coater includes at least one second opening (second discharge port) for discharging the (first) battery material. The second opening may be configured to coat the (first) battery material onto a web-type electrode substrate. The second opening defines a second opening width that extends in the lateral direction. The second opening width is smaller than the first opening width.

[0077] In the system according to this disclosure, the second opening is offset from the first opening downstream in the process direction. The second opening is also offset from the first opening in the lateral direction and includes a free portion located outside the first opening in the lateral direction. The free portion of the second opening is positioned to coat the (first) battery material, in particular, onto a web-type electrode substrate. The free portion defines a free width extending in the lateral direction.

[0078] Various embodiments of this disclosure will be described in detail below with reference to the accompanying drawings, so that those skilled in the art may easily do so. This disclosure can be modified in various other ways and is not limited to the embodiments presented herein.

[0079] Parts not relevant to the description may be omitted in order to clearly illustrate this disclosure, and the same reference numbers throughout the description refer to the same elements.

[0080] Furthermore, the size and thickness of each element in the drawings are shown arbitrarily for illustrative purposes, and this disclosure is not necessarily limited to those shown in the drawings. In the drawings, the thickness of layers, regions, etc., is exaggerated for clarity. In the drawings, the thickness of some layers and regions is exaggerated for illustrative purposes.

[0081] Furthermore, when an element such as a layer, film, region, or plate is described as being "on top of" or "above" another element, it can be understood that it may be directly on top of the other element, or an intermediate element may exist. Conversely, when an element is described as being "directly on top of" another element, it means that no other intermediate element exists. Also, the terms "on top of" or "above" mean being located above or below a reference part, and do not necessarily mean being located at the top edge of the reference part in the opposite direction of gravity. On the other hand, just as when an element is described as being located "on top of" or "above" another part, when an element is described as being located "below" or "below" another part, it can be understood by referring to the above.

[0082] Furthermore, throughout the description, when it is mentioned that a part "includes" or "constitutes" a particular component, it means that, unless otherwise explicitly stated, it may include other components without excluding the other components.

[0083] Furthermore, throughout the explanation, when "plan view" is mentioned, it refers to a view of the subject from above, and when "section view" is mentioned, it refers to a view of the subject from the side of a vertically cut section.

[0084] Figure 1 shows an exemplary apparatus 100 configured to perform the process of processing a web-type electrode substrate, realized from a metal foil web material 1, into an electrode web 2. The metal foil web material 1 generally has a thickness of only a few micrometers, a width of a few dm, and a length of more than 1 km. The metal foil web material 1 is supplied to a supply roll 10 and transported through the apparatus 100 according to the process direction indicated by the arrows.

[0085] Within the apparatus 100, a metal foil web material 1 moves along a number of deflection pulleys 130 and tension rollers 120. Some pulleys may be driven to apply a tensile force to the metal foil web material 1, while others may be free-spinning. The tension rollers 120 are configured to apply pressure to the sides of the metal foil web material 1 as it moves, changing its path to accommodate slight mismatches in travel speed and elasticity. The metal foil web material 1 passes through a die coater system 110, an example of a (first) battery material, configured and operated to supply an active material layer 3 to the metal foil web material to form an electrode web 2 according to the present disclosure. Downstream of the die coater system 110 is provided an oven 140 for curing the active material layer 3 and stabilizing the electrode web 2.

[0086] In the schematic illustration of the apparatus 100 shown in Figure 1, only one die coater system 110 and a subsequent oven 140 are shown, coating only the first side of the metal foil web material 1. It may be preferable (not shown) for the metal foil web material 1 to then pass through an additional die coater and a subsequent second oven to coat the opposite, second side of the metal foil web material, thereby producing an electrode web with active material layers supplied on both sides of the metal foil web material. One or more separation devices (not shown) for cutting individual sheets in the electrode web 2 may be provided in or downstream of the oven. The separation devices can be operated to produce individual electrode sheets for use in batteries.

[0087] Figure 2A shows a schematic illustration of an existing die coater 910. Figure 2B shows a schematic coating process using the die coater 910 of Figure 2A. For readability, the web-type electrode substrate is not shown in Figure 2A. Figure 2C shows a schematic cross-sectional view of an electrode made with the die coater 910 of Figure 2A.

[0088] The die coater 910 has rectangular slot-shaped outlets 915 from which a slurry 904 of the battery material is sprayed onto a material coating layer 905 on a first surface region 902 on the first side surface of the web-type electrode substrate 901. As shown in an exaggerated manner in Figure 2C, the side edges 907 of the battery material coating layer 905 have an irregular shape and an undesirable wavy geometric shape.

[0089] Figure 3A is a schematic illustration of a die coater system 210 according to the present disclosure. The system 210 manufactures an electrode web material by coating a web-type electrode substrate 1 that moves in the process direction P. The web-type electrode substrate 1 has a web width that extends in a lateral direction L perpendicular to the process direction P.

[0090] The die coater system 210 includes a first die coater 230 having a first opening 231 for coating an electrode substrate web 1 material with a (first) battery material. The first opening 231 defines a first opening width w extending in the lateral direction L. The system includes two second die coaters 240. Each second die coater 240 has at least one second opening 241. The second openings 241 each have a second opening width a extending in the lateral direction L. The second opening width a is substantially smaller than the first opening width w. Preferably, the second opening width a is 10% or less of the first opening width.

[0091] The second opening 241 is offset from the first opening 231 downstream in the process direction P. The second opening 241 is offset from the first opening 231 in the lateral direction L such that the second opening 241 includes a free portion located outside the first opening in the lateral direction L. In some embodiments, the second opening 241 further includes an overlapping portion that at least partially overlaps the first opening 231 in the lateral direction L, where the overlap width is preferably smaller than the free width (not shown in detail).

[0092] The second die coater 240 can be configured to move in the thickness T direction, which is perpendicular to the process direction and perpendicular to the lateral direction L. The first die coater 230 can be configured to move in the thickness T direction, which is perpendicular to the process direction and perpendicular to the lateral direction L.

[0093] To obtain an electrode having the cross-section shown in Figure 3C through a process of coating the electrode substrate shown in Figure 3B, a web-type electrode substrate 1 is provided and moved in a process direction P perpendicular to the lateral direction L corresponding to the web width direction. In Figure 3A, the discharge direction D from which the slurry is ejected coincides with the thickness direction T of the coating on the web-type electrode substrate 1. To coat the web-type electrode substrate 1, a certain amount of (first) battery material is applied to a first surface region 11 on the first side surface of the web-type electrode substrate 1 to form a first coated area 5. An additional amount of battery material is applied to a second surface region 13 on the first side surface of the web-type electrode substrate 1, offset from the first surface region 11 in the lateral direction L. The additional amount directly forms a second coated area 7 on the web-type electrode substrate 1 laterally adjacent to the first surface region 11. Thus, the additional amount creates a cover coated area 6 on the first surface region 11 extending over a portion of the first coated area 5. The second surface region 13 has a width of 10% or less of the first surface region 11 in the lateral direction.

[0094] The electrode substrate shown in Figure 3C includes a battery material coating portion 5 formed on the electrode substrate 1, which contains battery material. The battery material coating portion 5 includes contact surfaces 51 and 71 that contact the first surface region 11 of the electrode substrate 1, and an upper surface 53 opposite to the contact surface 51. The battery material layer formed by the first coating portion 5 and the second coating portion 7 includes an inclined edge portion 75 on the side edge, which defines an inclination width s that extends in the lateral direction L from the upper surface 53 toward the electrode substrate 1. The inclination width s is 1% or less of the width of the battery material coating portion.

[0095] Figure 4A is a schematic illustration of another die coater system 310. In die coater system 310, similar components are designated with the same reference numbers, increased by 100 compared to die coater system 210 described above.

[0096] The die coater system 310 differs from the die coater system 210 described above only in the following respect: In addition, a second battery material is applied to a third surface region on the first side of the web-type electrode substrate 1, which is laterally adjacent to the second surface region 13 on the opposite side of the first surface region 11. Thus, the second battery material is applied at least partially directly to the web-type electrode substrate 1 and at least partially on the second surface region 13. The second battery material is different from the first battery material. The second material layer at least partially covers the upper surface 53 of the battery material coating. The battery material coating portion is formed by a first coating portion and a first and possibly third coating portion. However, the third coating portion may preferably be formed of a dielectric material. The second coating portion 7 has a width of 50% or more of the cover coating portion 6.

[0097] Figure 4B shows a schematic illustration of a second die coater 340 for the die coater system 310 of Figure 4A. The second die coater 340 includes a second opening 341 and a third opening 342. The third opening 342 is offset from the first opening in the process direction P compared to the second opening 341. The second opening 341 has a second opening width a extending in the lateral direction L. The third opening 342 also has a third opening width b extending in the lateral direction L.

[0098] The third opening 342 is located adjacent to the second opening 341 and at least partially overlaps the second opening 341 laterally. The third opening 342 can be used to coat a second material containing a dielectric material. The second material layer is formed on the electrode substrate at its side edges.

[0099] Figure 5 is a schematic illustration of another second die coater 440 that can be used in the system according to the present disclosure. The second die coater 440 includes a second opening 441 and a third opening 442. The third opening 442 is offset from the first opening in the process direction P compared to the second opening. In the lateral direction L, the second opening 441 and the third opening 442 have the same position and width. The third opening 442 can be used to coat a second material containing a dielectric material. The second material layer is formed on the electrode substrate at the lateral edge.

[0100] While preferred embodiments of the Disclosure have been described in detail above, the scope of the Disclosure is not limited thereto, and includes a variety of modifications and improvements made by those skilled in the art using the basic concepts of the Disclosure as defined in the appended claims. [Explanation of symbols]

[0101] 1. Web-type electrode substrate 2 Electrode Web 3 Active material layer 4 Slurry 5. First coating section 6. Cover coating area 7 Side edge 10 supply rolls 11 1st surface area 13 Second surface area 51, 71 Contact area 53 Top 75. Sloping edge 100 devices 110 Daikota 120 Tension Roller 130 Deflection Pulley 140 oven 210 System 230 First Die Coater 231 First opening 240 Second Die Coater 241 Second opening 310 System 330 First Die Coater 331 First opening 340 Second Die Coater 341 Second opening 342 Third opening 440 Second Die Coater 441 Second opening 442 Third opening 901 Web Materials 902 Surface area 904 Slurry 905 Material coating layer 907 Side edge 910 Daikota 915 Outlet a, b 2nd opening width s slope width w First opening width D Discharge direction L Lateral direction P Process direction T (thickness direction)

Claims

1. A system configured to manufacture an electrode web material by coating a web-type electrode substrate that moves in the process direction and has a web width extending in a lateral direction perpendicular to the process direction, A first die coater including a first opening for coating a battery material onto the web-type electrode substrate, wherein the first opening is defined by a first die coater that defines a first opening width extending in the lateral direction, A second die coater including at least one second opening that defines the width of the second opening extending in the lateral direction, Includes, The width of the second opening is smaller than the width of the first opening. A system wherein the second opening is offset from the first opening downstream in the process direction and offset in the lateral direction, and the second opening includes a free portion located outside the first opening in the lateral direction.

2. The system according to claim 1, wherein the first die coater and / or the second die coater are configured to be movable in a thickness direction perpendicular to the process direction and perpendicular to the side direction.

3. The system according to claim 1 or 2, wherein the width of the second opening is 10% or less of the width of the first opening.

4. The system according to claim 1, wherein the second opening further includes an overlapping portion that at least partially overlaps the first opening in the lateral direction, and the width of the overlap is smaller than the width of the free portion.

5. The second die coater further includes a third opening, The third opening is offset from the first opening in the process direction compared to the second opening. The system according to claim 1, wherein the third opening is located adjacent to the second opening and at least partially overlaps the second opening in the lateral direction.

6. (a) The step of providing a web-type electrode substrate that defines a web width extending in the lateral direction, (b) A step of moving the web-type electrode substrate in a process direction perpendicular to the direction of the web width, (c) A step of applying a certain amount of first battery material to the first surface region of the first side surface of the web-type electrode substrate to form a first coated portion, (d) Apply an additional amount of the first battery material to the second surface region of the first side of the web-type electrode substrate, which is offset from the first surface region in the lateral direction. The steps include: forming a second coating portion directly on the web-type electrode substrate laterally adjacent to the first surface region, and forming a cover coating portion on the first surface region that extends at least partially over the first coating portion; A method for manufacturing electrodes, including the method described above.

7. The electrode manufacturing method according to claim 6, wherein the second surface region has a width in the lateral direction that is 10% or less of the width of the first surface region.

8. The electrode manufacturing method according to claim 6, wherein the second coating portion is 50% or more of the cover coating portion.

9. (e) The electrode manufacturing method according to claim 6, further comprising the step of applying a second battery material to a third surface area of ​​the first side of the web-type electrode substrate that is laterally adjacent to the second surface area on the opposite side of the first surface area, such that the second battery material is at least partially applied directly to the web-type electrode substrate and at least partially applied on the second surface area.

10. The electrode manufacturing method according to claim 9, wherein the second battery material is different from the first battery material.

11. Electrode substrate and A battery material coating portion including battery material formed on the electrode substrate, An electrode including, The aforementioned battery material coating portion is The contact surface that contacts the electrode substrate, The upper surface on the opposite side of the aforementioned contact surface, Includes, The layer of the battery material includes an inclined edge on at least one side edge of the battery material coating portion, the inclined edge defines an inclination width extending in the lateral direction and inclined from the upper surface toward the electrode substrate. The electrode wherein the inclination width is 1% or less of the width of the battery material coated portion.

12. Further comprising a second material coating portion containing a dielectric material, The electrode according to claim 11, wherein the second material layer is formed on the electrode substrate and the side edge.

13. The electrode according to claim 12, wherein the second material layer at least partially covers the upper surface of the battery material coated portion.

14. A battery comprising at least one electrode according to any one of claims 11 to 13, and / or an electrode manufactured using the method according to any one of claims 6 to 10.

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