Electrode plate, electrode plate manufacturing method, and electrode plate manufacturing apparatus

Abstract

The present disclosure provides an electrode plate, an electrode plate manufacturing method, and an electrode plate manufacturing apparatus. The electrode plate manufacturing apparatus of the present disclosure includes a substrate pressing unit that presses a substrate so that an inner portion of the substrate is thinner than an edge portion, a transfer unit that transfers the substrate, a first coating unit that coats a slurry on one surface of the substrate, a second coating unit that coats the slurry on the other surface of the substrate, and a slurry pressing unit that presses the slurry.

Description

Technical Field

[0001] This disclosure relates to electrode plates, manufacturing methods, and equipment for manufacturing electrode plates. Background Technology

[0002] Rechargeable batteries are manufactured in various shapes, among which pouch batteries include an electrode assembly and a thin, flexible pouch. The electrode assembly has a separator that acts as an insulator, inserted between positive and negative electrode plates, and is embedded within the thin, flexible pouch. The pouch typically houses the electrode assembly within its internal space.

[0003] Electrode assemblies in rechargeable batteries are broadly classified into wound and stacked types based on their structure. Stacked types offer better structural safety and desired or improved space utilization, making them widely used in small to medium-sized batteries. A stacked rechargeable battery is a rechargeable battery in which multiple electrodes and separators are stacked together.

[0004] As rechargeable batteries become smaller and lighter, their volumetric energy density and gravimetric energy density can be increased to achieve high output. For this purpose, a thin film thickness in the substrate constituting the electrode plates can be advantageous.

[0005] Figure 1 This is a cross-sectional view showing a conventional electrode plate.

[0006] Reference Figure 1 The conventional electrode plate 1 has active material layers 3 on both sides of the thin film substrate 2. In this way, if the substrate 2 is excessively or significantly thinned (when the substrate 2 is excessively or significantly thinned), a break may occur in the region adjacent to the edge portion of the substrate 2 where the active material layer 3 is not provided, and a short circuit may occur within the electrode assembly because the diaphragm adjacent to the broken portion is torn. Summary of the Invention

[0007] This disclosure addresses the aforementioned conventional challenges and describes an electrode plate capable of reducing or preventing breakage in a thin-film substrate, as well as a method for manufacturing the electrode plate and an apparatus for manufacturing the electrode plate.

[0008] However, the technical challenges to be addressed in this disclosure are not limited to those described above, and those skilled in the art will clearly understand from the description of this disclosure below that there are other tasks not mentioned.

[0009] An electrode plate manufacturing apparatus according to an exemplary embodiment of the present disclosure includes: a substrate extrusion unit for extruding a substrate such that the inner portion of the substrate becomes thinner than the edge portion; a conveying unit for conveying the substrate; a first coating unit for coating a slurry onto one surface of the substrate; a second coating unit for coating a slurry onto another surface of the substrate; and a slurry extrusion unit for extruding the slurry.

[0010] The substrate extrusion unit may include a plurality of substrate extrusion rollers, each substrate extrusion roller having a central portion protruding relative to an edge portion, the plurality of substrate extrusion rollers being spaced apart from each other to form a pair of rollers or more pairs of rollers, and the rollers in each pair being positioned relative to each other at a predetermined or desired distance.

[0011] The distance between a pair of substrate extrusion rollers at the far end of the multiple substrate extrusion rollers, based on the substrate conveying direction, is in the range of about 3 μm to about 5 μm.

[0012] The substrate extrusion roller may include: a side portion having a first diameter and located on each side of the substrate extrusion roller; and a protrusion having a second diameter and positioned inward relative to the side portion, the second diameter being relatively larger than the first diameter.

[0013] The portion of the protruding part adjacent to the side part can be chamfered.

[0014] The substrate extrusion roller may include side portions located on each side of the substrate extrusion roller and protrusions located inside the substrate extrusion roller such that its diameter gradually decreases from the center to the side portions.

[0015] The substrate extrusion unit may include: a support member having a central portion protruding beyond the edge portion; and an extrusion member located above the support member, the extrusion member having a central portion protruding beyond the edge portion and configured to move downward onto the support member to extrude the transported substrate.

[0016] The first coating unit may be or include a slot coating machine that coats slurry onto the inner portion of a substrate.

[0017] The second coating unit may be or may include a slot coating machine that coats slurry onto the inner portion of a substrate.

[0018] The paste extrusion unit can extrude the paste, causing it to bulge outward from the substrate.

[0019] The method for manufacturing an electrode plate according to the present disclosure includes: a substrate extrusion step, extruding the substrate such that the inner portion of the substrate becomes thinner than the edge portion; a substrate transfer step for transferring the substrate; a first coating step, coating a slurry onto one surface of the substrate; a second coating step, coating a slurry onto another surface of the substrate; and a slurry extrusion step, extruding the slurry.

[0020] In the substrate extrusion process, the substrate is extruded in multiple steps in sequence, so that the thickness of the substrate gradually decreases.

[0021] In the substrate extrusion step, the internal portion of the substrate, excluding the edge portion, is extruded using an extrusion molding method.

[0022] In the first coating step, the paste is applied to the interior portion of the substrate, excluding the edge portions.

[0023] In the second coating step, the slurry is applied to the interior portion of the substrate, excluding the edge portions.

[0024] An electrode plate according to an example of the present disclosure includes: a substrate including a base portion located at an edge of the electrode plate and an inlet portion positioned inward relative to the base portion and having a thickness relatively thinner than the base portion; and an active material layer located on at least one surface of the substrate.

[0025] The substrate may also include an inclined portion, which is formed at an angle at the boundary between the inlet portion and the base portion.

[0026] The entrance section can be formed such that the thickness gradually increases from the middle section to the base section.

[0027] The thickness of the inlet can be in the range of approximately 3 μm to approximately 5 μm.

[0028] The thickness of the substrate can be in the range of approximately 7 μm to approximately 9 μm.

[0029] According to this disclosure, the electrode plate manufacturing equipment can manufacture the uncoated edge portion of the substrate to have a relatively thicker thickness than other portions. Therefore, even when the substrate is thinner, breakage can be reduced or prevented, and thus short circuits in the electrode assembly can be reduced or prevented. Furthermore, a thinner substrate can improve the manufacturing quality of the rechargeable battery.

[0030] According to examples of this disclosure, the electrode plate manufacturing apparatus can manufacture rechargeable batteries with high capacity and high energy density by producing structurally stable thin-film substrates. Furthermore, it can manufacture rechargeable batteries with improved stability compared to batteries of the same capacity. Attached Figure Description

[0031] The accompanying drawings illustrate exemplary embodiments of this disclosure and, together with the detailed description of this disclosure that follows, are intended to further understand the technical ideas of this disclosure. Therefore, this disclosure should not be construed as being limited to the matters set forth in the drawings.

[0032] Figure 1 This is a cross-sectional view showing a conventional electrode plate.

[0033] Figure 2 This is a perspective view showing a rechargeable battery.

[0034] Figure 3 This is a cross-sectional view showing an electrode plate according to a first exemplary embodiment of the present disclosure.

[0035] Figure 4 This is a cross-sectional view showing an electrode plate according to a second exemplary embodiment of the present disclosure.

[0036] Figure 5 This is a cross-sectional view showing an electrode plate according to a third exemplary embodiment of the present disclosure.

[0037] Figure 6 This is a cross-sectional view showing an electrode plate manufacturing apparatus according to an exemplary embodiment of the present disclosure.

[0038] Figure 7 From Figure 6 A side view of the substrate extrusion unit obtained in the electrode plate manufacturing equipment.

[0039] Figure 8 From Figure 6 A perspective view of the substrate extrusion unit selected and shown in the electrode plate manufacturing equipment.

[0040] Figure 9A and 9B This is a cross-sectional view showing a substrate extrusion roller including protrusions according to a modified example.

[0041] Figure 10 This is a perspective view of the substrate extrusion unit according to a modified example, viewed from below.

[0042] Figure 11 This is a flowchart illustrating a method for manufacturing an electrode plate according to an exemplary embodiment of the present disclosure. Detailed Implementation

[0043] In the following, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as limited to their ordinary or dictionary meanings, but should be defined as needed to best describe the present disclosure. The present disclosure may be interpreted using terms and concepts consistent with the technical features of the present disclosure. Therefore, the exemplary embodiments described in this disclosure and the configurations shown in the accompanying drawings are merely some exemplary embodiments of the present disclosure and do not represent all the technical ideas of the present disclosure. It should be understood that various equivalents and modifications may exist that can replace the exemplary embodiments.

[0044] When used in this specification, the terms “comprising,” “including,” and / or “including…” describe the presence of the mentioned shapes, quantities, steps, actions, components, elements, and / or groups, and do not exclude the presence or addition of one or more other shapes, quantities, actions, components, elements, and / or groups.

[0045] To aid in understanding this disclosure, the dimensions of some components may be exaggerated rather than shown in the drawings to actual scale. In different embodiments, the same reference numerals may be assigned to the same components.

[0046] Referring to two items as "identical" implies that they are "substantially identical." Therefore, substantial equality can include cases with deviations considered small within the industry (such as deviations within 5%). Furthermore, the fact that any parameter is uniform within a predetermined or expected region can mean that the parameter is uniform from an average point of view.

[0047] It should be understood that although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. The terms first, second, etc., are used only to distinguish one component from another, and unless otherwise stated, the first component may be the second component.

[0048] Throughout the instruction manual, each part may be singular or plural unless explicitly stated otherwise.

[0049] The arrangement of any structure on the “upper (or lower)” or “above (or below)” of a component can mean that any structure is configured to contact the top (or bottom) surface of the component, and other structures can be inserted between the component and any structures configured on (or below) the component.

[0050] When a component is described as being “on,” “connected to,” or “joined to” another component, it should be understood that the components may be directly connected or joined to each other, but other components may also be “inserted” between these components, or each component may be “connected” or “joined” by other components.

[0051] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Additionally, when the phrase “may” is used in the description of exemplary embodiments of this disclosure, the phrase “may” refers to “one or more exemplary embodiments of this disclosure.” The phrase “at least one” or similar expression following a column of elements modifies the entire column, but not any individual element within that column.

[0052] When “A and / or B” is mentioned throughout the specification, unless otherwise stated, it means A, B, or A and B, and when “C to D” is mentioned, unless otherwise stated, it means C or greater and D or less.

[0053] When using phrases such as "at least one of A, B, and C" or "at least one of A, B, or C" to describe a list of elements A, B, and C, these phrases can refer to any appropriate combination of these elements.

[0054] The term "use" may be considered synonymous with the term "utilize". As used in this specification, the terms "substantially", "approximately", and similar terms are used as approximate terms rather than terms of degree and are intended to take into account the inherent deviations of measured or calculated values ​​as recognized by one of ordinary skill in the art. When the terms "approximately" or "substantially" are used in conjunction with numerical values ​​in this specification, it means that the relevant numerical value includes a tolerance of ±5% around said value. When a range is specified, the range includes all values ​​within which increments such as 0.1% are included.

[0055] Although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. The terms are used to distinguish one element, component, region, layer, or segment from another. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0056] For ease of description, spatial relational terms such as "below," "under," "down," "above," and "above" are used herein to describe the relationship between one element or feature and another element or feature as shown in the accompanying drawings. Spatial relative position is understood to encompass not only the orientation shown in the figures but also different orientations of the device during use or operation. For example, if the device in the figures is flipped (when the device in the figures is flipped), an element described as "below" another element is understood as "above" another element. Therefore, the term "below" can encompass both upward and downward directions.

[0057] The terminology used herein is for the purpose of describing exemplary embodiments of this disclosure and is not intended to limit this disclosure.

[0058] Before describing the electrode plate manufacturing apparatus according to an exemplary embodiment of the present disclosure, a rechargeable battery that can be manufactured using the electrode plate manufacturing apparatus according to an exemplary embodiment of the present disclosure will be described.

[0059] Figure 2 This is a perspective view showing a rechargeable battery.

[0060] Reference Figure 2 The rechargeable battery 10 may include an electrode assembly 20 and a housing 50.

[0061] The electrode assembly 20 includes a plurality of electrode plates 30 and a diaphragm 40. More specifically, the plurality of electrode plates 30 may include a first electrode plate 30A and a second electrode plate 30B.

[0062] Such an electrode assembly 20 may be in the form of a stack including a first electrode plate 30A, a second electrode plate 30B and a diaphragm 40 that is repeatedly wound or stacked.

[0063] For example, electrode assembly 20 may be or include a stacked type, wherein electrode plates 30 are arranged in multiple layers. Alternatively, electrode assembly 20 may be or include a repeatedly wound jelly roll type. In this disclosure, electrode assembly 20 is described as a stacked type by way of example.

[0064] On the other hand, in the manufacturing process of the stacked electrode assembly 20, a first stacking process and a second stacking process are typically performed.

[0065] In the first stacking process, a double-sided positive electrode (all positive electrode) and a double-sided negative electrode (all negative electrode) can be stacked together. In this example, the double-sided positive electrode (all positive electrode) can be any of the remaining first electrode plates 30A other than the outermost first electrode plate 30A. Furthermore, the double-sided negative electrode (all negative electrode) can be a second electrode plate 30B.

[0066] During the second stacking process, a single-sided positive electrode (semi-positive electrode) can be stacked on one or more of the outermost electrodes based on the stacking direction. In this example, the single-sided positive electrode can be the outermost first electrode plate 30A of the first electrode plate 30A.

[0067] although Figure 2 The electrode assembly 20 is shown in which a single-sided positive electrode is stacked on the topmost outermost portion of the electrode assembly 20, but a single-sided positive electrode can be stacked on each of the topmost outermost portion and the bottommost outermost portion of the electrode assembly 20.

[0068] In this example, the double-sided positive and double-sided negative electrodes have active material layers coated on both surfaces of the substrate, and the single-sided positive electrode has an active material layer located only on one surface of the substrate. Detailed descriptions of such double-sided positive, double-sided negative, and single-sided positive electrodes are omitted.

[0069] A diaphragm 40 can be inserted between the first electrode plate 30A and the second electrode plate 30B. The diaphragm 40 reduces or prevents the occurrence of short circuits between the first electrode plate 30A and the second electrode plate 30B, and allows lithium ions to move through it. For this purpose, the diaphragm 40 can have a relatively larger size than the first electrode plate 30A and the second electrode plate 30B.

[0070] The diaphragm 40 may comprise a porous polymer membrane or a porous nonwoven fabric. In this example, the porous polymer membrane may be formed of or comprise a single layer or multiple layers, said single layer or multiple layers comprising at least one of polyolefin polymers such as ethylene polymers, propylene polymers, ethylene / butene copolymers, ethylene / hexene copolymers, and ethylene / methacrylate copolymers. The porous nonwoven fabric may comprise glass fibers and polyethylene terephthalate fibers having high melting points. However, the porous nonwoven fabric is not limited thereto, and depending on the example embodiment, the diaphragm may be or comprise a high-temperature resistant diaphragm (CCS; ceramic-coated diaphragm) containing ceramics.

[0071] The diaphragm 40 can be cut into unit lengths and placed between the first electrode plate 30A and the second electrode plate 30B, or a single diaphragm 40 formed as a strip can be placed between the first electrode plate 30A and the second electrode plate 30B in a zigzag or twisted manner. Alternatively, the diaphragm 40 can be wound in one direction between the first electrode plate 30A and the second electrode plate 30B.

[0072] The arrangement of the diaphragm 40 is not limited to a specific form, but in this example embodiment, the diaphragm 40 is cut into unit lengths and disposed between the first electrode plate 30A and the second electrode plate 30B.

[0073] The housing 50 can accommodate the electrode assembly 20. The electrode assembly 20 is housed together with the electrolyte solution in the housing 50.

[0074] For example, the electrolyte solution can be a non-aqueous electrolyte solution. The electrolyte solution may include lithium salts and organic solvents. The organic solvents may include at least one of propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), dipropyl carbonate (DPC), vinylene carbonate (VC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, sulfolane, γ-butyrolactone, propylene sulfide, and tetrahydrofuran.

[0075] For example, the housing 50 can be any of the following types: bag-shaped, cylindrical, and prismatic. The bag-shaped housing 50 can be manufactured by bending the sheet-like outer material to face each other, then compressing or stretching one of its surfaces, and including a recess on said one surface.

[0076] The electrode assembly 20 is housed in a recess (not shown). A sealing portion 50a is provided at the outer periphery of the recess, and the sealing portion 50a can seal the electrode assembly 20 while it is housed in the recess by a method such as thermal welding.

[0077] Meanwhile, the first electrode plate 30A may be or include a negative electrode, and the second electrode plate 30B may be or include a positive electrode; however, the opposite configuration is also possible. The first electrode plate 30A may include a first substrate terminal block 61 extending to the outside, and the second electrode plate 30B may include a second substrate terminal block 62 extending to the outside.

[0078] The first substrate terminal block 61 can be formed by cutting the current collector layer (not shown) of the first electrode plate 30A using a laser grooving device, and the second substrate terminal block 62 can be formed by cutting the current collector layer (not shown) of the second electrode plate 30B using a laser grooving device.

[0079] The first substrate connector 61 and the second substrate connector 62 can be electrically connected to the outside of the rechargeable battery 10 via the strip terminal 52. Furthermore, an insulating tape 51 can be attached to the portion of the strip terminal 52 that contacts the housing 50. The insulating tape 51 prevents electrical connection between the strip terminal 52 and the housing 50.

[0080] Meanwhile, the rechargeable battery 10 that can be manufactured using the electrode plate manufacturing equipment according to an exemplary embodiment of the present disclosure is not limited to the above structure.

[0081] Figure 3 This is a cross-sectional view showing an electrode plate according to a first exemplary embodiment of the present disclosure.

[0082] Reference Figure 3 According to a first exemplary embodiment of this disclosure, the electrode plate 30 includes a substrate ST and active material layers AM1 and AM2. In this example, the slurries S1 and S2 coated on the substrate ST are dried (see...). Figure 6 To form active material layers AM1 and AM2.

[0083] The substrate ST includes a base portion ST2 and an entrance portion ST1. The base portion ST2 is located at the edge of the electrode plate 30. The entrance portion ST1 is located inside the base portion ST2 and has a relatively thinner thickness than the base portion ST2.

[0084] In this example, the thickness T1 of the inlet portion ST1 can range from about 3 μm to about 5 μm. Additionally, the thickness T2 of the substrate portion ST2 can range from about 7 μm to about 9 μm. More preferably, the thickness T2 of the substrate portion ST2 can be about 8 μm.

[0085] The substrate ST may be or include a current collector, and the current collector may include a known conductive material within the range that does not cause a chemical reaction in the rechargeable battery. For example, the current collector may include any or more of stainless steel, nickel (Ni), aluminum (Al), titanium (Ti), copper (Cu), and their alloys, and may be provided in various forms such as films, sheets, and foils.

[0086] The active material layers AM1 and AM2 are located on at least one surface of the substrate ST. That is, the active material layers AM1 and AM2 can be located on one or both surfaces of the substrate ST.

[0087] Since the active material layers AM1 and AM2 can be located on the entrance portion ST1 of the substrate ST, the active material layers AM1 and AM2 can be spaced apart from the edge of the substrate ST. A protective film (not shown) can also be attached to the boundary between the edge of the active material layers AM1 and AM2 and the substrate ST.

[0088] For example, when electrode plate 30 is a positive electrode plate, the positive electrode plate may include a positive electrode active material layer. The positive electrode active material layer may include a positive electrode active material.

[0089] As a positive electrode active material, compounds capable of reversibly inserting and deintercalating lithium (lithiation intercalation compounds) can be used.

[0090] For example, a composite oxide of lithium and at least one metal (such as or including at least one of cobalt, manganese, nickel and combinations thereof) can be used.

[0091] The above-mentioned composite oxides may be or include lithium transition metal composite oxides, and examples include at least one of the following: lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0092] As an example, a compound represented by any of the following chemical formulas can be used. Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b-c Mn b X c O 2-αD α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2);Li a Ni b Co c L 1d GeO2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); LiaCoGbO2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b GbO2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2GbO4 (0.90≤a≤1.8,0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3 (0≤f≤2); Li a FePO4 (0.90≤a≤1.8).

[0093] In the above chemical formula, A is or includes at least one of Ni, Co, Mn or a combination thereof; X is or includes at least one of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or a combination thereof; D is or includes at least one of O, F, S, P or a combination thereof; G is or includes at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; and L1 is or includes at least one of Mn, Al or a combination thereof.

[0094] Additionally, when electrode plate 30 is a negative electrode plate, the negative electrode plate may include a negative electrode active material layer. The negative electrode active material layer may include a negative electrode active material.

[0095] The negative electrode active material includes at least one of the following: a material capable of reversibly inserting / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0096] The material capable of reversibly intercalating / deintercalating lithium ions may be or include a carbon-based negative electrode active material, such as crystalline carbon, amorphous carbon, or a combination thereof. Examples of the crystalline carbon may include graphite, such as natural graphite or artificial graphite, and examples of the amorphous carbon may include at least one of soft carbon or hard carbon, mesophase pitch carbide, calcined coke, and the like.

[0097] As the material capable of doping and dedoping lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material may be used. The Si-based negative electrode active material may be or include at least one of the following: silicon, a silicon-carbon composite, SiO x (0<x<2), a Si-based alloy, or a combination thereof.

[0098] The silicon-carbon composite may be or include a composite of silicon and amorphous carbon. According to an example embodiment, the silicon-carbon composite may be in the form of silicon particles and amorphous carbon coated on surfaces of the silicon particles.

[0099] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core comprising crystalline carbon and silicon particles, and an amorphous carbon coating located on a surface of the core.

[0100] For example, the active material layers AM1 and AM2 may further include a binder (not shown) and a conductive material (not shown).

[0101] The binder (not shown) may facilitate bonding between the substrate ST and the active material, thereby improving mechanical stability. For example, the binder may be or include an organic binder or an aqueous binder, and may be used together with a thickener such as carboxymethyl cellulose CMC. For example, the organic binder may be any one or more of vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride PVDF, polyacrylonitrile, and polymethyl methacrylate, and the aqueous binder may be or include styrene-butadiene rubber SBR, but is not limited thereto.

[0102] The conductive material (not shown) may improve the conductivity of the rechargeable battery. The conductive material may include a metal-based material. For example, the conductive material may include a conventional carbon-based conductive material. In an example, the conductive material may include any one or more of graphite, carbon black, graphene, and carbon nanotubes. For example, the conductive material may include carbon nanotubes, but is not limited thereto.

[0103] Figure 4 is a cross-sectional view illustrating an electrode plate according to a second example embodiment of the present disclosure.

[0104] Referring to Figure 4 , the substrate ST included in the electrode plate 31 according to the second example embodiment of the present disclosure may further include an inclined portion C.

[0105] The inclined portion C is inclined at the boundary between the inlet portion ST1 and the base portion ST2. The inclined portion C can increase the rigidity of the boundary between the inlet portion ST1 and the base portion ST2. Accordingly, the rigidity of the substrate ST is increased, thereby reducing or preventing breakage.

[0106] Figure 5 This is a cross-sectional view showing an electrode plate according to a third exemplary embodiment of the present disclosure.

[0107] See Figure 5 According to a third exemplary embodiment of this disclosure, the thickness of the entrance portion ST1 of the substrate ST included in the electrode plate 32 can gradually increase from the middle portion towards the base portion ST2. The electrode plate 32 according to the third exemplary embodiment can have a thickness greater than that of the electrode plate 31 (see...). Figure 4 The rigidity of the ST1 inlet section has been further improved.

[0108] The electrode plates 30, 31, and 32 according to this disclosure can have the same total thickness as conventional electrode plates, and can have a base portion ST2 with a thickness greater than that of the inlet portion ST1. Therefore, compared with the substrate of conventional electrode plates, the substrate ST included in the electrode plates 30, 31, and 32 according to this disclosure exhibits significantly improved rigidity, thereby reducing or preventing breakage.

[0109] Hereinafter, an electrode plate manufacturing apparatus 100 capable of manufacturing the electrode plate 30 as described above will be described in detail with reference to the accompanying drawings.

[0110] Figure 6 This is a cross-sectional view showing an electrode plate manufacturing apparatus according to an exemplary embodiment of the present disclosure. (Refer to...) Figure 6 The electrode plate manufacturing apparatus 100 according to an exemplary embodiment of the present disclosure includes a substrate extrusion unit 110, a conveying unit 120, a first coating unit 130, a second coating unit 140, and a slurry extrusion unit 150.

[0111] Substrate extrusion unit 110 extrusion Figures 3 to 5 The substrate ST shown is such that its interior portion is thinner than its edge portion. When the substrate ST, having a uniform or substantially uniform total thickness, is conveyed to the substrate extrusion unit 110, the substrate extrusion unit 110 can extrude the substrate ST to produce... Figures 3 to 5 The entrance section ST1 is shown.

[0112] Therefore, the substrate extrusion unit 110 may include a plurality of substrate extrusion rollers 111.

[0113] Multiple substrate extrusion rollers 111 are arranged in pairs, with two rollers spaced apart from each other. Each substrate extrusion roller 111 has a central portion protruding beyond its edge. The pairs of substrate extrusion rollers 111 are positioned at a predetermined or desired distance from each other. Figure 6 As shown.

[0114] For example, the substrate extrusion unit 110 may include six substrate extrusion rollers 111. Two substrate extrusion rollers 111 may be positioned vertically spaced apart, and each pair of substrate extrusion rollers 111A, 111B, and 111C may be positioned at a predetermined or desired interval, such as... Figure 7 As shown.

[0115] In this example, the gap between each pair of substrate extrusion rollers 111A, 111B, and 111C can gradually decrease along the transport direction of the substrate ST. Therefore, the substrate ST can have a target thickness. A detailed description of the shape of the substrate extrusion roller 111 is described below.

[0116] The transfer unit 120 transfers the substrate ST from a given process to the next process.

[0117] For this purpose, for example, the transfer unit 120 may be or include means for transferring the substrate ST in a roll-to-roll method. For example, a substrate ST that is relatively thicker than the substrate ST included in the finally manufactured electrode plate 30 may be unwound from a dewinder (not shown).

[0118] Subsequently, as the substrate ST is sequentially pressed by the substrate pressing unit 110, the thickness of the substrate ST decreases, and the entrance portion ST1 can be formed simultaneously (see reference). Figure 4 Furthermore, the substrate ST processed by the first coating unit 130, the second coating unit 140 and the slurry extrusion unit 150, which will be described below, can be wound onto a rewinder (not shown).

[0119] Therefore, the aforementioned conveying unit 120 may include, for example, a pair of conveying rollers 123 positioned to contact the upper and lower surfaces of the substrate ST and located at specific positions along the conveying direction of the substrate ST. That is, the metal foil of the substrate ST, which can be used as the electrode plate 30 of the rechargeable battery 10, can be conveyed in one direction by contacting multiple conveying rollers 123. The positions of the conveying rollers 123 are not limited to specific positions but can vary depending on the design of the electrode plate manufacturing equipment 100.

[0120] Furthermore, the conveying unit 120 may include a first support roller 121 and a second support roller 122. The first support roller 121 may be positioned adjacent to the first coating unit 130, which will be described below, and the second support roller 122 may be positioned adjacent to the second coating unit 140, which will be described below.

[0121] The first support roller 121 is positioned on the opposite side of the first coating unit 130, wherein the substrate ST is inserted between the first support roller 121 and the first coating unit 130. When the first coating unit 130 coats the first slurry S1 onto the substrate ST, the first support roller 121 can stably support the substrate ST while changing the conveying direction of the substrate ST.

[0122] The second support roller 122 is positioned on the opposite side of the second coating unit 140, wherein the substrate ST is inserted between the second support roller 122 and the second coating unit 140. When the second coating unit 140 coats the second slurry S2 onto the substrate ST, the second support roller 122 can stably support the substrate ST while changing the conveying direction of the substrate ST.

[0123] The first coating unit 130 coats the first slurry S1 onto one surface of the substrate ST. The first coating unit 130 may be, for example, a slot coating machine for coating the first slurry S1 onto an inner portion of the substrate ST. Figure 6 As shown, the first coating unit 130 can coat the first slurry S1 onto the inlet portion ST1 of the substrate ST, but not onto the base portion ST2 of the substrate ST.

[0124] At the same time, such as Figure 3 As shown, the electrode plate 30 according to an exemplary embodiment of the present disclosure has an inlet portion ST1 that is relatively thinner than the substrate portion ST2. Therefore, if the first coating unit 130 coats the inlet portion ST1 of the substrate ST with the first slurry S1 (when the first coating unit 130 coats the inlet portion ST1 of the substrate ST with the first slurry S1), the first slurry S1 can remain on the inlet portion ST1 without overflowing into the substrate portion ST2 due to its own viscosity. As described above, unlike conventional electrode plates, the electrode plate 30 according to the exemplary embodiment of the present disclosure can have improved slurry coating quality. The same effect can be achieved even when the next second coating unit 140 coats the substrate ST with the second slurry S2.

[0125] The second coating unit 140 coats the second slurry S2 onto another surface of the substrate ST. The second coating unit 140 may be, for example, a slot coating machine for coating the second slurry S2 onto an inner portion of the substrate ST.

[0126] Although not shown in the accompanying drawings, a slot coater (such as, for example, a first coating unit 130 and / or a second coating unit 140) may include nozzles having one or more discharge ports. The slot coater is configured to precisely apply slurry to a specific thickness and area.

[0127] The slot coater receives slurry from a slurry storage unit (not shown). The slurry can be applied uniformly or substantially uniformly to the substrate ST through the outlet after being injected into the nozzle. A detailed description of the slot coater is omitted herein.

[0128] Although not shown in the accompanying drawings, the electrode plate manufacturing apparatus 100 according to an exemplary embodiment of the present disclosure may include a drying unit (not shown).

[0129] The drying unit dries the slurries S1 and S2. The drying unit may include, for example, one or more heaters. The heaters may be mounted spaced apart from the substrate ST. The heaters dry the slurry by converting electrical energy into heat energy.

[0130] The drying unit can be positioned after each of the first coating unit 130 and the second coating unit 140, based on the transport direction of the substrate ST. The slurry applied to the substrate ST can evaporate its internal solvent to form an electrode mixture while passing through the drying unit.

[0131] The drying unit can be any device capable of forming an electrode mixture by evaporating solvent from the slurry. For example, the drying unit can perform drying and can be a heated or hot air type drying unit. A detailed description of the drying unit is omitted here.

[0132] The paste extrusion unit 150 pressurizes the pastes S1 and S2. The paste extrusion unit 150 can pressurize the pastes S1 and S2 so that the pastes S1 and S2 protrude outward relative to the substrate ST.

[0133] For example, the slurry extrusion unit 150 extrudes the slurry, making the slurry thickness uniform or substantially uniform. In other words, the slurry extrusion unit 150 can roll... Figures 3 to 5 The dried active material layers AM1 and AM2 shown in the diagram give the electrode mixture the desired porosity and electrode density.

[0134] The slurry extrusion unit 150 is not limited in its device, structure, etc., as long as the slurry extrusion unit 150 has a structure capable of rolling the electrode mixture. The slurry extrusion unit 150 may include a pair of slurry extrusion rollers 151, which are arranged opposite each other with the substrate ST inserted therebetween, and are configured to adjust the separation distance between them.

[0135] Figure 7 From Figure 6 A side view of the substrate extrusion unit obtained in the electrode plate manufacturing equipment. Figure 8 It shows from Figure 6 A perspective view of the substrate extrusion unit of the electrode plate manufacturing equipment.

[0136] Reference Figure 7 and Figure 8 The substrate extrusion roller 111 may include, for example, a side portion 112 and a protruding portion 113A.

[0137] The side portion 112 has a first diameter and can be located on each of the two sides of the substrate extrusion roller 111.

[0138] The protrusion 113A may have a second diameter that is relatively larger than the first diameter of the side portion 112, and may be located inside the side portion 112. The substrate extrusion roller 111 can be manufactured... Figure 3 The substrate ST shown in the figure.

[0139] For example, Figure 7 The distance H between a pair of substrate extrusion rollers 111C located at the edges of the plurality of substrate extrusion rollers 111A, 111B and 111C shown can be in the range of about 3 μm to about 5 μm. Therefore, the thickness of the thinnest part of the substrate ST can be in the same range of about 3 μm to about 5 μm.

[0140] When the substrate ST is manufactured to have a thickness of less than about 3 μm, the thickness of the center of the substrate ST is too thin or very thin, and therefore it may be prone to breakage. If the substrate ST is manufactured to have a thickness of more than about 5 μm, it may be difficult to achieve a thin film of the substrate ST.

[0141] As described above, the electrode plate manufacturing apparatus 100 according to an exemplary embodiment of this disclosure (see Figure 6 The thickness of the final manufactured substrate ST can be set by changing the distance H between a pair of substrate extrusion rollers 111C (see [reference]). Figure 6 ).

[0142] Figure 9A and 9B This is a cross-sectional view showing a substrate extrusion roller including a protruding portion according to a modified example.

[0143] Reference Figure 9A In a modified example, the protrusion 113B included in the substrate extrusion roller 111 may be chamfered in the portion 114 adjacent to the side portion 112. The substrate extrusion roller 111 can be manufactured... Figure 4 The substrate ST shown in the figure.

[0144] Reference Figure 9B In another variation, the protrusion 113C included in the substrate extrusion roller 111 can be formed such that its diameter gradually decreases from the center toward the side portion 112. Such a substrate extrusion roller 111 can be manufactured Figure 5 The substrate ST shown in the figure.

[0145] The substrate extrusion unit 110 described above can quickly form an inlet portion ST1 on the conveyed substrate ST.

[0146] Figure 10 This is a perspective view of the substrate extrusion unit according to a modified example, viewed from below.

[0147] Reference Figure 10 According to the modified example, the substrate extrusion unit 210 may include a support member 211 and an extrusion member 212.

[0148] The support member 211 protrudes more in the middle portion than at the edges. The support member 211 can be positioned on the substrate (ST, see figure) based on the orientation shown in the figure. Figure 6 Below.

[0149] The extrusion member 212 is located above the support member 211, and its middle portion protrudes more than its edge portions. The extrusion member 212 descends to the support member 211 to apply pressure to the substrate ST being transported.

[0150] Therefore, the substrate extrusion unit 210 according to the modified example can be used to manufacture... Figure 3 The substrate ST shown is also described. Alternatively, it can be manufactured by replacing the support member 211 and the extrusion member 212 with different shapes. Figure 4 and Figure 5 The substrate ST shown.

[0151] Hereinafter, the method for manufacturing electrode plate 30 using the electrode plate manufacturing equipment 100 described above will be described with reference to the accompanying drawings.

[0152] Figure 11 This is a flowchart illustrating a method for manufacturing an electrode plate according to an exemplary embodiment of the present disclosure.

[0153] Reference Figure 11 The method for manufacturing an electrode plate according to an exemplary embodiment of the present disclosure includes a substrate extrusion step S110, a substrate transfer step S120, a first coating step S130, a second coating step S140, and a slurry extrusion step S150.

[0154] The substrate extrusion step S110 is a step in which the substrate is extruded so that the inner portion of the substrate becomes thinner than the edge portion of the substrate. The substrate extrusion step S110 can be performed by, for example, a substrate extrusion unit 110 (see...). Figure 6 )implement.

[0155] In the substrate extrusion step S110, the substrate can be extruded sequentially through several steps (see...). Figure 6 This gradually reduces the thickness of the substrate. Alternatively, in the substrate extrusion step S110, extrusion can be performed using an extrusion molding method (see...). Figure 10The interior portion of the substrate, excluding the edges of the substrate.

[0156] The substrate transfer step S120 is the step of transferring the substrate. The substrate transfer step S120 can be performed by the transfer unit 120 (see reference 120). Figure 6 )implement.

[0157] The first coating step S130 is a step of coating a paste onto one surface of the substrate. The first coating step S130 can be performed by, for example, a first coating unit 130 (see...). Figure 6 The process is as follows: In the first coating step S130, the paste may be applied to the inner portion of the substrate, excluding the edges of the substrate.

[0158] The second coating step S140 is a step of coating a paste onto another surface of the substrate. The second coating step S140 can be performed by, for example, a second coating unit 140 (see...). Figure 6 The process is performed. In the second coating step S140, the paste may be coated on the inner portion of the substrate, excluding the edges.

[0159] The paste extrusion step S150 is a step of extruding paste. In the paste extrusion step S150, the paste can be extruded so that it protrudes outward relative to the substrate. The paste extrusion step S150 can be performed by, for example, a paste extrusion unit 150 (see...). Figure 6 )implement.

[0160] Since the method for manufacturing an electrode plate according to an exemplary embodiment of this disclosure has already been described in detail while describing the electrode plate manufacturing equipment, its description is omitted.

[0161] Although various exemplary embodiments of this disclosure have been described above, the accompanying drawings and detailed description of this disclosure, referenced to this point, are merely examples and are intended to explain the purpose of this disclosure only, and not to limit the scope of the disclosure as described in the claims. Therefore, those skilled in the art will understand that various modifications and other equivalent exemplary embodiments are possible. Consequently, the true technical scope of this disclosure should be determined by the technical concept of the appended claims.

[0162] Explanation of reference numerals in the attached figures:

[0163] 10: Rechargeable batteries

[0164] 20: Electrode assembly; 30, 31, 32: Electrode plates

[0165] ST: Substrate; ST2: Base layer

[0166] ST1: Entrance AM1: First Active Material Layer

[0167] AM2: Second active material layer C: Inclined portion

[0168] 100: Electrode plate manufacturing equipment

[0169] 110, 210: Substrate extrusion unit; 111: Substrate extrusion roller

[0170] 112: Side portion; 113A, 113B, 113C: Protruding portion

[0171] 211: Supporting member; 212: Extrusion member

[0172] 120: Conveying unit; 121: First support roller

[0173] 122: Second support roller; 123: Conveyor roller

[0174] 130: First coating unit; 140: Second coating unit

[0175] 150: Slurry extrusion unit; 151: Slurry extrusion roller

Claims

1. An electrode plate manufacturing apparatus, comprising: A substrate extrusion unit extrudes a substrate such that the interior portion of the substrate becomes thinner than the edge portion of the substrate. A transmission unit is configured to transmit the substrate; The first coating unit is configured to coat a slurry onto one surface of the substrate; The second coating unit is configured to coat the slurry onto another surface of the substrate; as well as A slurry extrusion unit is configured to extrude the slurry.

2. The electrode plate manufacturing equipment according to claim 1, wherein, The substrate extrusion unit includes: Multiple substrate extrusion rollers, each substrate extrusion roller having a central portion protruding relative to an edge portion, the multiple substrate extrusion rollers being spaced apart from each other to form a pair of rollers or more pairs of rollers, and the rollers in each pair being positioned at a desired distance from each other.

3. The electrode plate manufacturing equipment according to claim 2, wherein: The distance between a pair of substrate extrusion rollers located at the far end of the plurality of substrate extrusion rollers, based on the conveying direction of the substrate, is in the range of 3 μm to 5 μm.

4. The electrode plate manufacturing equipment according to claim 2, wherein, The substrate extrusion roller includes: The side portion has a first diameter and is located on each side of the substrate extrusion roller; and The protruding portion has a second diameter that is larger than the first diameter and is positioned inward relative to the side portion.

5. The electrode plate manufacturing equipment according to claim 4, wherein: The portion of the protruding part adjacent to the side portion is chamfered.

6. The electrode plate manufacturing equipment according to claim 2, wherein, The substrate extrusion roller includes: Side portions, located on each side of the substrate extrusion rollers; and The protruding portion, located inside the substrate extrusion roller, has a diameter that gradually decreases from the center toward the side portion.

7. The electrode plate manufacturing equipment according to claim 1, wherein, The substrate extrusion unit includes: A supporting member having a middle portion that protrudes beyond the edge portion; and An extrusion member, located above the support member, has a central portion protruding beyond the edge portion and is configured to move downward onto the support member to extrude a substrate therebetween.

8. The electrode plate manufacturing equipment according to claim 1, wherein: The first coating unit is a slot coating machine configured to coat the slurry onto the inner portion of the substrate.

9. The electrode plate manufacturing equipment according to claim 1, wherein: The second coating unit is a slot coating machine configured to coat the slurry onto the inner portion of the substrate.

10. The electrode plate manufacturing equipment according to claim 1, wherein: The slurry extrusion unit extrudes the slurry, causing the slurry to bulge outward from the substrate.

11. A method for manufacturing an electrode plate, comprising: The substrate extrusion step involves extruding the substrate so that the interior portion of the substrate becomes thinner than the edge portion of the substrate; The substrate transfer step involves transferring the substrate. The first coating step involves coating a slurry onto one surface of the substrate. The second coating step involves coating the slurry onto another surface of the substrate. as well as The slurry extrusion step involves extruding the slurry.

12. The method for manufacturing an electrode plate according to claim 11, wherein: In the substrate extrusion step, the substrate is extruded sequentially through multiple steps, thereby gradually reducing the thickness of the substrate.

13. The method for manufacturing an electrode plate according to claim 11, wherein: In the substrate extrusion step, the internal portion of the substrate, excluding the edge portion, is extruded by an extrusion molding method.

14. The method for manufacturing an electrode plate according to claim 11, wherein: In the first coating step, the slurry is applied to the inner portion of the substrate, excluding the edge portion.

15. The method for manufacturing an electrode plate according to claim 11, wherein: In the second coating step, the slurry is applied to the inner portion of the substrate, excluding the edge portion.

16. An electrode plate, comprising: The substrate includes a base portion located at the edge of the electrode plate and an inlet portion positioned inward relative to the base portion and having a thickness relatively thinner than the base portion; as well as An active material layer is located on at least one surface of the substrate.

17. The electrode plate according to claim 16, wherein: The substrate also includes an inclined portion at the boundary between the inlet portion and the base portion.

18. The electrode plate according to claim 16, wherein: The thickness of the inlet portion gradually increases from the middle portion to the base portion.

19. The electrode plate according to claim 16, wherein: The thickness of the inlet portion is in the range of 3 μm to 5 μm.

20. The electrode plate according to claim 16, wherein: The thickness of the substrate is in the range of 7 μm to 9 μm.

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