Electrode for rechargeable lithium battery, apparatus for manufacturing electrode, and rechargeable lithium battery

Abstract

The present application relates to an electrode for a rechargeable lithium battery, an apparatus for manufacturing an electrode, and a rechargeable lithium battery. The electrode for a rechargeable lithium battery includes a current collector and a dry electrode film provided in a region of the current collector. The region includes a plurality of protrusions extending from the current collector. The dry electrode film is in contact with the plurality of protrusions in the region. An average height of the plurality of protrusions is greater than 1.0 μm.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2025-0056971, filed on April 30, 2025, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to electrodes for rechargeable lithium batteries, apparatus for manufacturing electrodes for rechargeable lithium batteries, and rechargeable lithium batteries. Background Technology

[0004] With the rapid proliferation of battery-powered electronic devices such as mobile phones, laptops, and electric vehicles, the demand for rechargeable lithium batteries with high energy density and high capacity is increasing rapidly. Correspondingly, research and development efforts have been undertaken to improve the performance of rechargeable lithium batteries.

[0005] A rechargeable lithium battery includes a positive electrode and a negative electrode, as well as an electrolyte. The positive and negative electrodes contain active materials capable of inserting and deintercalating lithium ions. When lithium ions are inserted into or deintercalated from the positive and negative electrodes, the rechargeable lithium battery generates electrical energy through oxidation and reduction reactions.

[0006] Dry electrode films comprise electrode active materials, binders, conductive materials, etc. They are manufactured in the form of films, tapes, or sheets without solvents. To form uncoated portions in electrodes including dry electrode films, methods for patterning current collectors using adhesion-promoting layers have been developed. However, this method has low processability and may be economically unfeasible because patterning must typically be performed according to battery specifications. In another method, the dry electrode film is laminated to the entire surface of the current collector, and then only a portion of the dry electrode film is removed. However, this method can damage the current collector and / or the dry electrode film.

[0007] The information disclosed in this section is intended to enhance understanding of the background of this disclosure and may contain information that does not constitute related technology or prior art. Summary of the Invention

[0008] This disclosure relates to providing electrodes for rechargeable lithium batteries, apparatus for manufacturing electrodes for rechargeable lithium batteries, and rechargeable lithium batteries that do not have an adhesion-promoting layer, but still have high adhesion between the current collector and the dry electrode film, are easy to form uncoated portions, and have excellent manufacturability.

[0009] However, the technical objectives to be addressed by this disclosure are not limited, and those skilled in the art will clearly understand from the following description of this disclosure other objectives not described herein.

[0010] According to an aspect of this disclosure, an electrode for a rechargeable lithium battery is provided, comprising a current collector and a dry electrode film provided in a region of the current collector, wherein a plurality of protrusions extend from the current collector in the region, the dry electrode film contacts the plurality of protrusions, and the average height of the protrusions is greater than 1.0 μm.

[0011] According to another aspect of this disclosure, an apparatus for manufacturing electrodes for rechargeable lithium batteries is provided, comprising: a current collector transfer unit configured to transfer a current collector including a plurality of protrusions extending from the current collector; a current collector pressing unit configured to press a region of the current collector transferred from the current collector transfer unit; a dry electrode film rolling unit configured to laminate a dry electrode film onto the current collector transferred from the current collector pressing unit and roll the dry electrode film; and a dry electrode film removal unit configured to remove a dry electrode film corresponding to the pressed current collector from the laminate of the current collector and the dry electrode film transferred from the dry electrode film rolling unit.

[0012] According to another aspect of this disclosure, a rechargeable lithium battery is provided, which includes an electrode for a rechargeable lithium battery or an electrode for a rechargeable lithium battery manufactured by means of an apparatus for manufacturing an electrode for a rechargeable lithium battery. Attached Figure Description

[0013] The accompanying drawings illustrate embodiments of the present disclosure and, together with the following detailed description, serve to provide a further understanding of the technical spirit of the present disclosure. However, the present disclosure is not limited to the embodiments set forth in the drawings.

[0014] Figure 1 A schematic diagram of a current collector and a dry electrode film that are laminated but not rolled.

[0015] Figure 2 This is a schematic diagram of a current collector and a dry electrode film laminated and rolled in a first region of an electrode according to an embodiment of the present disclosure.

[0016] Figure 3 This is a magnified image showing the interface between the current collector and the dry electrode film in an electrode according to an embodiment of the present disclosure.

[0017] Figure 4 A magnified image of a current collector with multiple protrusions formed on it before it is laminated onto a dry electrode film.

[0018] Figure 5 This is a magnified image of a second region in an electrode according to an embodiment of the present disclosure.

[0019] Figure 6 A first region and a second region of an electrode according to an embodiment of the present disclosure are shown.

[0020] Figure 7 A first region and a second region of an electrode according to another embodiment of the present disclosure are shown.

[0021] Figure 8 This is a diagram of an apparatus for manufacturing electrodes for rechargeable lithium batteries according to an embodiment of the present disclosure.

[0022] Figure 9 This is a diagram of an apparatus for manufacturing electrodes for rechargeable lithium batteries according to an embodiment of the present disclosure.

[0023] Figure 10 This is a diagram of an apparatus for manufacturing electrodes for rechargeable lithium batteries according to an embodiment of the present disclosure.

[0024] Figures 11-14 This is a schematic diagram of a rechargeable lithium battery according to an embodiment of the present disclosure. Detailed Implementation

[0025] The embodiments of this disclosure will now 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 having a general or dictionary meaning, but rather as meanings and concepts consistent with the technical ideas of this disclosure, based on the principle that the inventor can be his / her own lexicographer to appropriately define the concepts of the terms in order to best describe his / her invention.

[0026] The embodiments described in this specification and the configurations shown in the accompanying drawings are only some embodiments of this disclosure and do not represent the full technical spirit, aspects, and features of this disclosure. Accordingly, it should be understood that various equivalent schemes and modifications that can replace or modify the embodiments described herein can be made at the time of filing this application.

[0027] It will be understood that when an element or layer is described as being "on," "connected to," or "attached to" another element or layer, it may be directly on, connected to, or attached to the other element or layer, or one or more intermediary elements or layers may be present. When an element or layer is described as being "directly on," "directly connected to," or "directly attached to" another element or layer, no intermediary elements or layers are present. For example, when a first element is described as being "attached" or "connected" to a second element, the first element may be directly attached to or connected to the second element, or the first element may be indirectly attached to or connected to the second element via one or more intermediary elements.

[0028] In the accompanying drawings, the dimensions of individual elements, layers, etc., may be enlarged for clarity. The same reference numerals label the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated enumerated items. Furthermore, when describing embodiments of this disclosure, the use of "may" refers to "one or more embodiments of this disclosure." Expressions such as "at least one of" and "any one," when preceding / following a list of elements, modify the entire list of elements and not individual elements in the list. When phrases such as "at least one of A, B, and C," "at least one selected from the group of A, B, and C," or "at least one selected from A, B, and C" are used to label a list of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the terms "use," "using," and "used" are to be considered synonymous with the terms "utilize," "utilizing," and "utilized," respectively. As used herein, the terms “substantially,” “about,” and similar terms are used as approximate terms and not as terms of degree, and are intended to describe the inherent variations in measured or calculated values ​​that would be recognized by one of ordinary skill in the art.

[0029] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0030] For ease of description, spatial relative terms, such as “below,” “under,” “down,” “above,” “above,” etc., may be used herein to describe the relationship between one element or feature and another, as illustrated in the accompanying drawings. It will be understood that spatial relative terms are intended to encompass different orientations of the device in use or operation, in addition to those depicted in the accompanying drawings. For example, if the device in the accompanying drawings is flipped, an element described as “below” or “under” other elements or features will be oriented “above” or “above” other elements or features. Thus, the term “below” can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or otherwise), and the spatial relative descriptors used herein may be interpreted accordingly.

[0031] The terminology used herein is intended to describe embodiments of the present disclosure and is not intended to limit the full scope of the disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes,” “including,” “comprises,” and / or “comprising,” when used in this specification, indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0032] Any numerical range disclosed and / or set forth herein is intended to include all subranges containing the same numerical precision within the set forth range. For example, the range “1.0 to 10.0” is intended to include all subranges between (and inclusive of) the stated minimum value of 1.0 and the stated maximum value of 10.0, i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit set forth herein is intended to include all lower numerical limits contained herein, and any minimum numerical limit set forth in this specification is intended to include all higher numerical limits contained herein. Accordingly, the applicant reserves the right to amend this specification (including the claims) to expressly set forth any subranges contained within the range expressly set forth herein. All such ranges are intended to be inherently described in this specification such that amendments to expressly set forth any such subranges will comply with the requirements of patent law and applicable regulations.

[0033] Referring to two comparisons as “same” in terms of elements, features, etc., can imply that they are “substantially identical.” Therefore, the phrase “substantially identical” can include cases where the difference is considered low in the field (e.g., 5% or less). Additionally, when a parameter is said to be uniform in a given region, this can mean that it is uniform in terms of average value.

[0034] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0035] Placing an element "above (or below)" or "on (below)" another element can mean that the element can be configured to contact the upper (or lower) surface of the element, and that the other element can be inserted between the element and the element positioned above (or below) the element.

[0036] Additionally, it will be understood that when a component is referred to as “link,” “connect,” or “attached” to another component, the component can be directly “connected,” “linked,” or “attached” to each other, or another component can be “inserted” into the components.

[0037] Throughout this specification, when “A and / or B” is stated, it means A, B, or A and B, unless otherwise stated. That is, “and / or” includes any or all combinations of the listed items. Unless otherwise indicated, when “C to D” is stated, it means C or more and D or fewer.

[0038] Electrodes for rechargeable lithium batteries

[0039] An electrode (hereinafter referred to as "electrode") for a rechargeable lithium battery according to an embodiment of the present disclosure is a dry electrode comprising a dry electrode film. The electrode includes a current collector comprising a first region and a dry electrode film on at least one surface of the current collector located in the first region.

[0040] The current collector does not include an adhesion-promoting layer. For example, the current collector may not include an adhesion-promoting layer in a first region. Here, "adhesion-promoting layer" means a layer located on the surface of the current collector to increase the adhesion between the current collector and the dry electrode film. Such an adhesion-promoting layer may include a primer layer. The primer layer may be formed from a composition comprising a conductive material and an adhesive. "Adhesion-promoting layer" may also be a general term for a layer in a dry electrode film that increases the adhesion between the current collector and the dry electrode film.

[0041] The first region includes a plurality of protrusions formed extending from the current collector. The protrusions extend from the current collector to a predetermined height. When the current collector and the dry electrode film are laminated and rolled, the protrusions can penetrate deep into the dry electrode film to provide an anchoring effect that physically couples the current collector and the dry electrode film. Accordingly, the dry electrode film and the protrusions can come into close contact with each other to increase the adhesion between the current collector and the dry electrode film. The protrusions provide adhesion to the dry electrode film.

[0042] Figure 1 and Figure 2 This illustrates how multiple protrusions in an electrode according to an embodiment of the present disclosure improve the adhesion between the current collector and the dry electrode film. Figure 1 A schematic diagram of a current collector and a dry electrode film that are laminated but not rolled. Figure 1 This shows the state in which the current collector and dry electrode film are laminated without being rolled. Figure 2 This is a schematic diagram of a current collector and a dry electrode film laminated and rolled in a first region of an electrode according to an embodiment of the present disclosure. Figure 2 The diagram shows the state in which a current collector and a dry electrode film are laminated and rolled in a first region of an electrode according to an embodiment of the present disclosure.

[0043] refer to Figure 1 It is a state in which a dry electrode film 210, including active material 211 and binder, is laminated onto a current collector 200 including multiple protrusions 201a without rolling.

[0044] refer to Figure 2 A dry electrode I is formed by laminating and rolling the current collector 200 and the dry electrode film 210. In the dry electrode I, protrusions 201 penetrate the dry electrode film 210, thereby increasing the adhesion between the current collector 200 and the dry electrode film 210 compared to a current collector without protrusions. Here, the term "adhesion" refers to the force required to peel the dry electrode film from the current collector under specific conditions, and can be defined as a value measured using a 180° peel test method.

[0045] Although not in Figure 2 As shown, however, multiple protrusions can penetrate deep into the dry electrode film, such that at least a portion of the dry electrode film in the first region is located between the protrusions.

[0046] Figure 3 This is an enlarged image showing the interface between the current collector and the dry electrode film in an electrode according to an embodiment of the present disclosure.

[0047] refer to Figure 3 As can be seen, the protrusions extend from the current collector and penetrate deep into the dry electrode film. Therefore, the current collector and the dry electrode film are in close contact with each other, allowing the protrusions to effectively replace the conventional adhesion-promoting layer.

[0048] According to the embodiment, the average height of the protrusion can be greater than 1.0 μm, for example, in the range of 1.5 μm to 2.5 μm. The average height of the protrusion is set to provide a first region with high adhesion to the dry electrode film and a second region without the dry electrode film. Here, "average height" is the average height of the protrusions in the current collector, and specifically the average height from the surface of the current collector to the highest point of the protrusion. The average height can be determined using high-resolution scanning electron microscopy (HR-SEM) images captured by cross-sectional processing using a cross-section polisher (CP), focused ion beam (FIB), etc., or by measuring the average height from the lowest point to the highest point of the protrusion using non-destructive methods (such as analytical methods using laser microscopy). Here, "protrusion height" can refer to the vertical distance from one end of the protrusion to the current collector when the nodule extends from the current collector in a direction perpendicular to the current collector, and can also refer to the vertical distance from the surface of the current collector to the highest point of the protrusion when the nodule extends from the current collector in a direction other than perpendicular to the current collector.

[0049] According to the embodiment, the average spacing between the multiple protrusions can be greater than 1.0 μm, for example, in the range of 2.0 μm to 3.5 μm, 2.0 μm to 3.0 μm, or 2.0 μm to 2.5 μm. Within these ranges, the extent to which the protrusions penetrate into the dry electrode film can be increased, thereby facilitating increased adhesion between the dry electrode film and the current collector. Here, "average spacing" can be the average value of the intervals between the protrusions in the current collector, and can be measured in the same manner as height by image analysis or non-destructive analysis.

[0050] In some embodiments, the protrusions may have a needle-like shape. Protrusions with a needle-like shape can easily penetrate into the dry electrode film, which can facilitate increased adhesion between the current collector and the dry electrode film.

[0051] Figure 4 A magnified image of a current collector with multiple protrusions formed on it before lamination onto the dry electrode film. (Reference) Figure 4 Multiple protrusions may have a needle-like shape, with their highest surface protruding sharply, which helps to increase adhesion.

[0052] There are no limitations on the method of forming multiple protrusions, provided that the protrusions formed on the current collector have the above-described shape, average height, and average spacing. However, in one example where the protrusions are integrally formed with the current collector, the protrusions may be formed by plating.

[0053] According to an embodiment, multiple protrusions can be formed on the current collector by plating. The plating can be electroplating or chemical plating, but electroplating is preferred.

[0054] Electroplating can be performed by the methods described below, but this disclosure is not limited thereto. The following description relates to cases where the current collector is formed of copper foil, but this disclosure is not limited thereto.

[0055] Electroplating can be performed as follows: an aqueous solution comprising nickel and copper salts is adjusted to a pH of 1-5 (e.g., 2-4) to prepare an electrolyte; a current collector and an insoluble positive or negative electrode are introduced into the electrolyte; and then electroplating is performed at an electrolyte temperature of 25°C-45°C and 1 A / dm³. 2 ~5A / dm 2 Electrolysis is performed at a current density of 1 to 5 seconds. Examples of nickel salts include nickel sulfate, nickel nitrate, nickel chloride, and nickel acetate, which can be used alone or in combination of two or more. However, this disclosure is not limited to these examples. Examples of copper salts include copper sulfate, copper nitrate, copper chloride, and copper acetate, which can be used alone or in combination of two or more. However, this disclosure is not limited to these examples.

[0056] The concentrations of nickel and copper salts in the electrolyte can be adjusted according to the average height of the protrusions.

[0057] Electroplating can be performed in an electrolyte comprising the aforementioned nickel and copper salts. However, electroplating can also be performed using an aqueous solution comprising copper salts and sulfuric acid. Examples of copper salts include copper sulfate, copper nitrate, copper chloride, and copper acetate, which can be used alone or in combination of two or more, but this disclosure is not limited thereto. Electroplating can be performed by introducing the current collector and insoluble electrode as positive or negative electrodes into the electrolyte, and maintaining a solution temperature of 25°C to 45°C and a concentration of 10 A / dm³. 2~ 20 A / dm 2 Electrolysis is performed at a current density of 1 to 5 seconds. However, this disclosure is not limited thereto.

[0058] Because multiple protrusions extend from and protrude from the current collector, they can be crushed when the current collector is pressed down without laminating the dry electrode film. This makes it impossible to achieve the aforementioned anchoring effect.

[0059] To avoid this situation, a second region for the current collector can be formed. According to an embodiment, the second region may be an uncoated portion of the electrode.

[0060] Accordingly, the electrode may include a current collector having a first region and a second region formed adjacent to the first region. The second region may be an uncoated portion in which no dry electrode film is provided.

[0061] The second region may include a plurality of protrusions formed extending from the current collector. The protrusions in the second region may have a lower average height than the protrusions in the first region. Therefore, when the dry electrode film is laminated onto the current collector and rolled, the adhesion between the current collector and the dry electrode film can be reduced to facilitate the removal of the dry electrode film, which makes it easier to form the second region as an uncoated portion.

[0062] Figure 5 This is an enlarged image of the second region in an electrode according to an embodiment of the present disclosure. It can be seen that the protrusions in the second region have been crushed. It can also be seen that... Figure 5 Compared to the protrusions in the middle, Figure 3 The protrusions in the middle retain more of a needle-like shape.

[0063] The average height of the protrusions in the second region can be lower than the average height of the protrusions in the first region. Therefore, it is beneficial to form a second region, which is an uncoated portion, in the dry electrode.

[0064] According to an embodiment, the average height of the protrusions in the second region can be 1.0 μm or less, for example, in the range of 0 μm to 1.0 μm. Within this range, it is advantageous to remove the dry electrode film from the current collector. Here, the average height of the protrusions in the second region can be measured in the same manner as described above regarding the average height of the protrusions in the first region.

[0065] Figure 6 A first region and a second region of an electrode according to an embodiment of the present disclosure are shown.

[0066] refer to Figure 6 Electrode II includes a current collector 200 comprising a first region 220A and a second region 220B. A dry electrode film 220 comprising an active material 211 and a binder is formed in the first region 220A, and no dry electrode film is formed in the second region 220B.

[0067] Multiple protrusions 201 included in the first region 220A can penetrate deep into the dry electrode film 220 to increase the adhesion between the current collector 200 and the dry electrode film 220. The average height of the multiple protrusions 202 formed in the second region 220B is lower than the average height of the multiple protrusions 201 formed in the first region 220A.

[0068] Dry electrode films can be formed on one surface of the current collector or on two opposing surfaces of the current collector.

[0069] Figure 7 A first region and a second region of an electrode according to another embodiment of this disclosure are shown. Reference Figure 7 Except that each of the dry electrode film 220, the first region 220A, and the second region 220B is formed on two opposing surfaces of the current collector 200, electrode III and Figure 6 Electrode II is basically the same.

[0070] The multiple protrusions formed in the second region can be formed simultaneously with the multiple protrusions formed in the first region. Therefore, the electrode manufacturing process can be improved. The multiple protrusions in the first region and the multiple protrusions in the second region are formed on the current collector by plating.

[0071] Multiple protrusions are formed on one or both opposing surfaces of the current collector by the above-described plating process. However, initially only the protrusions in the second region of the current collector are pressed, and a dry electrode film is laminated onto the entire surface of the current collector and rolled. Then, only the dry electrode film corresponding to the second region is removed to form the electrode. Therefore, in the electrode, the current collector can be used to simultaneously form the first and second regions, with protrusions formed by electroplating and without a patterned coating of an adhesion-promoting layer, thereby improving manufacturability and reducing the possibility of electrode damage.

[0072] The electrode according to the embodiments of this disclosure can be a negative electrode or a positive electrode. That is, the electrode can be a negative electrode or a positive electrode.

[0073] negative electrode

[0074] The negative electrode may include a current collector comprising a first region and a dry electrode film on at least one surface of the current collector in the first region, wherein the current collector in the first region may comprise a plurality of protrusions extending from the current collector. The dry electrode film may be in contact with the plurality of protrusions, and the dry electrode film may comprise a negative electrode active material and a binder.

[0075] The current collector is not particularly limited as long as it provides high electrical conductivity and does not cause undesired chemical changes in the battery. For example, the current collector may be made of stainless steel, aluminum, nickel, titanium, calcined carbon, copper, aluminum, or stainless steel coated with a conductive metal and surface-treated with carbon, nickel, titanium or silver, copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam or a polymer substrate.

[0076] The current collector may have a thickness of 1 μm to 30 μm, but the present disclosure is not particularly limited thereto. For example, the current collector may have a thickness of 3 μm to 20 μm and may be formed of copper foil.

[0077] The dry electrode film may comprise a negative electrode active material and a binder, and may optionally comprise electrode powder comprising a conductive material. The dry electrode film may be in the form of a film, strip or sheet having a predetermined thickness.

[0078] The negative electrode active material includes at least one of a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, a lithium metal alloy, a material capable of doping and undoping lithium, and a transition metal oxide.

[0079] The material capable of reversibly intercalating / deintercalating lithium ions may include a carbon-based negative electrode active material, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon include graphite, such as natural graphite or artificial graphite. Examples of amorphous carbon may include soft carbon, hard carbon, mesophase pitch carbide, and calcined coke.

[0080] As the material capable of doping and undoping 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 silicon, a silicon-carbon composite, SiO x (0<x<2), a Si-based alloy, or a combination thereof. According to an embodiment, the negative electrode active material includes at least one of a carbon-based negative electrode active material and a Si-based negative electrode active material.

[0081] The silicon-carbon composite may be a composite of silicon and amorphous carbon. According to an embodiment, the silicon-carbon composite may be in the form comprising silicon particles and an amorphous carbon coating.

[0082] The silicon-carbon composite may further comprise crystalline carbon. For example, the silicon-carbon composite may comprise a core comprising crystalline carbon and silicon particles, and amorphous carbon coating the surface of the core.

[0083] In specific examples, the negative electrode active material can have an average particle size D of 1 μm to 30 μm, for example, 4 μm to 20 μm. 50 The aforementioned current collectors can be used within these ranges.

[0084] The binder can be fibrillated during the fabrication of the dry electrode membrane. Fibrillation can be a process of finely dividing the polymer. For example, fibrillation can be performed using mechanical shearing forces. The surface of the fibrillated polymer fibers is unraveled to generate multiple fine fibers, and these fine fibers aggregate the electrode active material and / or conductive material, thereby ensuring the fabrication of the dry electrode membrane.

[0085] In a specific embodiment, the adhesive may include polytetrafluoroethylene (PTFE), polyolefin, or a mixture thereof. Specifically, the adhesive may include PTFE, and more specifically, may be PTFE. The amount of PTFE included relative to the total weight of the adhesive may be 60 wt% or more, for example, 90 wt% to 100 wt%.

[0086] In other embodiments, the adhesive may further comprise a non-fibrillated adhesive. The non-fibrillated adhesive may include at least one of, for example, polyethylene oxide, polyvinylidene fluoride, and polyvinylidene fluoride-hexafluoropropylene copolymer.

[0087] In some embodiments, the binder may be included in the dry electrode membrane in a fibrillated state.

[0088] Conductive materials may include: carbon black or graphite (such as natural or artificial graphite); conductive fibers (such as carbon fibers or metal fibers); fluorinated carbon, aluminum, and metal powders (such as nickel powder); conductive whiskers (such as zinc oxide or potassium titanate); conductive metal oxides (such as titanium oxide); or conductive materials (such as polyphenylene derivatives).

[0089] In this embodiment, the amount of negative electrode active material included in the dry electrode film can be 80 wt% to 99 wt%, for example, 90 wt% to 99.5 wt%; the amount of binder included can be 0.5 wt% to 20 wt%, for example, 0.5 wt% to 10 wt%; and the amount of conductive material included can be 0.5 wt% to 20 wt%, for example, 0.5 wt% to 10 wt%. Within these ranges, the manufacture of the dry electrode film is facilitated, and the PTFE fibrillation in the electrode can be promoted to improve mechanical strength.

[0090] positive electrode

[0091] The positive electrode may include a current collector having a first region and a dry electrode film located on at least one surface of the current collector in the first region. The current collector in the first region may include protrusions extending from the current collector. The dry electrode film may contact the protrusions, and the dry electrode film may include a positive electrode active material and a binder.

[0092] The current collector described above for the negative electrode can be used as a current collector for the positive electrode.

[0093] The dry electrode film may include a positive electrode active material and a binder, and may optionally include electrode powder containing a conductive material. The dry electrode film may be in the form of a film, strip, or sheet having a predetermined thickness.

[0094] As the positive electrode active material, compounds capable of reversibly inserting and deintercalating lithium (lithiation-intercalated compounds) can be used. Specifically, a composite oxide of lithium with at least one metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0095] The composite oxide can be a lithium transition metal composite oxide. Specific examples of lithium transition metal composite oxides include lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, cobalt-free nickel manganese oxides, or combinations thereof. 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 Where 0.90≤a≤1.8, 0≤b≤0.5, and 0≤c≤0.05; Li a Mn 2−b X b O 4−c D c Where 0.90≤a≤1.8, 0≤b≤0.5, and 0≤c≤0.05; Li a Ni 1−b−c Co b X c O 2−α D α Where 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, and 0<α<2; Li a Ni 1−b−c Mn b X c O 2−α D α Where 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, and 0<α<2; Li a Ni b Co c L 1 d Ge O2, where 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, and 0 ≤ e ≤ 0.1; Li a NiG b O2, where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1; Li a CoG b O2, where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1; Li a Mn 1−b G b O2, where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1; Li a Mn2G b O4, where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1; Li a Mn 1−g G g PO4, where 0.90 ≤ a ≤ 1.8 and 0 ≤ g ≤ 0.5; Li (3−f) Fe2(PO4)3, where 0 ≤ f ≤ 2; and Li a FePO4, where 0.90 ≤ a ≤ 1.8. In these formulas, A is Ni, Co, Mn or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or a combination thereof; D is O, F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; and L 1 It is Mn, Al, or a combination thereof.

[0096] In specific examples, the positive electrode active material can have an average particle size D of 0.1 μm to 30 μm, for example, 0.5 μm to 20 μm. 50 The aforementioned current collectors can be used within these ranges.

[0097] The binder and conductive material are essentially the same as those described above for the negative electrode.

[0098] In this embodiment, the amount of positive electrode active material included in the dry electrode film can be 80 wt% to 99 wt%, for example, 90 wt% to 99.5 wt%; the amount of binder included can be 0.5 wt% to 20 wt%, for example, 0.5 wt% to 10 wt%; and the amount of conductive material included can be 0.5 wt% to 20 wt%, for example, 0.5 wt% to 10 wt%. Within these ranges, the manufacture of the dry electrode film is facilitated, and the PTFE fibrillation in the electrode can be promoted to improve mechanical strength.

[0099] Dry electrode films can be fabricated by the following operations. The following methods can be applied to each of the negative and positive electrodes:

[0100] (a) Preparation of a powder mixture comprising electrode active material, binder and conductive material;

[0101] (b) Kneading the powder mixture to prepare a mixture agglomerates;

[0102] (c) Crushing the mixture clumps to obtain electrode powder; and

[0103] (d) Calendering electrode powder to obtain a self-supporting dry electrode film.

[0104] First, the electrode active material, binder, and conductive material are mixed to prepare a powder mixture. Mixing is performed so that the electrode active material and binder are uniformly distributed throughout the mixture. Because the electrode active material and binder are mixed in powder form, there are no particular limitations to the mixing process, as long as the mixing ensures that the electrode active material and binder are incorporated. However, because the mixture is used to prepare a dry electrode film, it does not contain a solvent. Mixing can be performed by dry mixing (e.g., by introducing the material into a device such as a blender).

[0105] In this embodiment, there is no particular limitation on the mixing time, but mixing can take from 1 second to 10 minutes. There is no limitation on the mixing speed, but it can be appropriately controlled within the range of approximately 3,000 rpm to 30,000 rpm. As a specific example, the mixture can be prepared by mixing in a mixer at a speed of 5,000 rpm to 20,000 rpm for 30 seconds to 2 minutes, specifically, at a speed of 10,000 rpm to 15,000 rpm for 30 seconds to 5 minutes, thereby providing high uniformity and control over the crystallinity of the binder resin.

[0106] Next, the mixture obtained above is subjected to a kneading process to fibrillate the binder. Kneading is an operation that couples or connects the electrode active material and / or conductive material to form a mixture agglomerate with a solid content of 100 wt% while fibrillating the binder.

[0107] Specifically, the kneading can be controlled at a speed of 10 rpm to 100 rpm. For example, the kneading can be controlled at a speed of 40 rpm to 70 rpm within the above range. The kneading can be performed for 1 minute to 30 minutes. For example, the kneading can be performed for 3 minutes to 7 minutes within the above range at a speed of 40 rpm to 70 rpm. The shear rate during kneading can be controlled within the range of 10 / s to 500 / s. In a specific embodiment of this disclosure, the kneading can be performed for 1 minute to 30 minutes, and the shear rate can be controlled within the range of 30 / s to 100 / s.

[0108] Kneading can be carried out at high temperatures and pressures greater than or equal to atmospheric pressure, and more specifically, at pressures greater than atmospheric pressure. More specifically, kneading can be carried out at temperatures ranging from 70°C to 200°C, specifically from 90°C to 150°C.

[0109] Furthermore, kneading can be performed at pressures greater than or equal to atmospheric pressure, specifically at 1 atm to 3 atm, or more specifically at 1.1 atm to 3 atm. When kneading is performed at pressures above this range, excessive shear forces and pressures are applied, which can cut the formed fibers or excessively increase the density of the mixture agglomerates, and this is undesirable. That is, according to this disclosure, the effects described herein can be achieved when a low-shear mixing process is performed, rather than a high-shear mixing process, under conditions of high temperature and pressure greater than or equal to atmospheric pressure.

[0110] Next, the mixture agglomerates prepared by kneading are further pulverized to obtain electrode powder. Specifically, the mixture agglomerates prepared by kneading can be directly calendered. However, the mixture agglomerates may need to be pressed at higher pressures and temperatures to form a thin film, which can lead to problems such as the film density becoming too high or the inability to obtain a uniform film. Therefore, the mixture agglomerates prepared by pulverization are preferred.

[0111] The grinding can be performed using known grinding devices (such as mixers or grinders), but this disclosure is not limited thereto. In specific embodiments of this disclosure, the grinding speed can be controlled within the range of 3,000 rpm to 30,000 rpm. The grinding time can be within the range of 1 second to 10 minutes. However, the grinding speed and time are not limited to these ranges. As a specific example, grinding can be performed at a speed of 5,000 rpm to 20,000 rpm for 30 seconds to 10 minutes or at a speed of 10,000 rpm to 18,000 rpm for 30 seconds to 5 minutes. Because sufficient grinding is performed within these ranges, film formation is facilitated, and the generation of fine powder can be reduced.

[0112] Electrode powder is heated and pressed to prepare a dry electrode film. Specifically, the electrode powder obtained by pulverizing as described above is introduced into a calendering process. The electrode powder is heated and pressed by the calendering process, and the electrode powder is processed into a dry electrode film in the form of a film, strip, or sheet. The calendering process can be performed using a pair of opposing calendering rolls. In an embodiment, the calendering process can be performed by passing the electrode powder between multiple calendering rolls.

[0113] Before the calendering process, the electrode powder can undergo a pretreatment process. This pretreatment can be performed by heating the electrode powder to a temperature of 80°C or higher, preferably 100°C or higher, for a predetermined time. The pretreatment process can last for one minute or longer, but the time can be adjusted according to the amount of powder. For example, the powder temperature can be maintained at 80°C or higher for one minute or longer, or at 100°C or higher for one minute or longer. Optionally, the heating temperature of the electrode powder is controlled to be below or equal to the melting point of the binder resin to prevent deterioration of the electrode components included in the electrode powder (such as the binder resin used). The heating temperature of the electrode powder can be controlled to be below or equal to 320°C. The pretreatment process can be performed using commonly used heating devices (such as convection ovens or infrared heating devices). Preferably, the electrode powder does not stagnate during stirring and heating.

[0114] Equipment for manufacturing electrodes for rechargeable lithium batteries

[0115] The following section describes the apparatus used to manufacture electrodes for rechargeable lithium batteries.

[0116] Apparatus for manufacturing electrodes for rechargeable lithium batteries can form electrodes including a first region and a second region. In other embodiments, the apparatus for manufacturing electrodes for rechargeable lithium batteries can be used to prepare electrodes including only a first region.

[0117] An apparatus for manufacturing electrodes for rechargeable lithium batteries includes: a current collector transfer unit configured to transfer a current collector, the current collector including a plurality of protrusions extending from the current collector; a current collector pressing unit configured to press a region of the current collector transferred from the current collector transfer unit; a dry electrode film rolling unit configured to laminate a dry electrode film onto the current collector transferred from the current collector pressing unit and roll the dry electrode film; and a dry electrode film removal unit configured to remove a dry electrode film corresponding to the pressed current collector in the laminate of the current collector transferred from the dry electrode film rolling unit and the dry electrode film.

[0118] The current collector transfer unit is a component that initiates the manufacture of electrodes by transferring current collectors with protrusions on one surface or two opposing surfaces.

[0119] In one embodiment, the current collector transfer unit may include components for unwinding the current collector from a roller wound thereon.

[0120] The multiple protrusions of the current collector, which expand through the current collector transfer unit, can be formed by plating the current collector. According to an embodiment, the multiple protrusions of the current collector in the current collector transfer unit can be formed on one surface (e.g., an entire surface) or two opposing surfaces of the current collector. The average height of the multiple protrusions of the current collector in the current collector transfer unit can be 1.5 μm or higher, for example, in the range of 2 μm to 5 μm or 2 μm to 3 μm. Within these ranges, the formation of the first and second regions in the electrode is advantageous.

[0121] The current collector pressing unit presses down a region of the current collector transferred from the current collector transfer unit. The current collector pressing unit can later reduce adhesion to the dry electrode film by pressing down the region of the current collector to crush any protrusions formed on the current collector in that region. This lower adhesion to the dry electrode film facilitates the formation of a second region.

[0122] There is no limitation on the current collector pressing unit, as long as the current collector pressing unit only presses one area of ​​the current collector. In a specific embodiment, the current collector pressing unit may include at least one of a pressing component comprising a floating roller, a laminating roller with a surface portion protruding, and a vertically movable laminating roller.

[0123] The pressing component including the floating roller includes a pressing component for pressing the area of ​​the current collector during transfer, and includes a floating roller for controlling the movement of the current collector. This will be referenced below. Figure 8 Describe in detail.

[0124] Because the surface portion of the laminating roller protrudes during the transfer of the current collector, as the laminating roller rotates, this protruding surface portion presses down on a portion of the current collector. This will be explained in the reference below. Figure 9 Describe in detail.

[0125] When transferring the current collector, the vertically movable laminating roller presses down a portion of the current collector and rotates only on the target section. This will be explained in the reference below. Figure 10 Describe in detail.

[0126] In a specific example, the current collector pressing unit can reduce the average height of the current collector protrusion transferred from the current collector transfer unit to 40% or less, or 30% or less. Within this range, it is advantageous for manufacturing the second region. For example, the current collector pressing unit can reduce the average height of the current collector protrusion to 1% to 30% or 5% to 25%.

[0127] The current collector pressing unit can press the current collector at a pressure of 0.1 tons / cm or higher and a temperature of 20℃ to 150℃.

[0128] The dry electrode film rolling unit laminates the dry electrode film onto the current collector transferred from the current collector pressing unit and rolls the dry electrode film, thereby laminating the dry electrode film onto the entire surface of the current collector and rolling the dry electrode film. The dry electrode film rolling unit may include apparatus for laminating and rolling the current collector and the dry electrode film as used in the manufacture of conventional dry electrode films.

[0129] According to an embodiment, the dry electrode film rolling unit includes components configured to roll dry electrode films at a temperature of 20°C to 150°C and a pressure of 0.01 tons / cm to 10 tons / cm.

[0130] The dry electrode film removal unit forms a second region by removing the dry electrode film corresponding to the pressed current collector in the laminate of the current collector and the dry electrode film transferred from the dry electrode film rolling unit. The dry electrode film removal unit may remove only the dry electrode film not attached to the current collector or attached with weak adhesion. The dry electrode film can be removed using conventional film removal devices known to those skilled in the art. For example, the dry electrode film removal unit may include a direct removal device that removes the dry electrode film by direct contact using a brush or tape followed by a vacuum suction device, or an indirect removal device that uses an ultrasonic generator, a laser, or an air knife. According to an embodiment, the dry electrode film removal unit includes at least one of a brush, tape, a vacuum suction device, an ultrasonic generator, a laser, and an air knife.

[0131] The multiple protrusions in the second region may have a low average height, which facilitates the fabrication of the dry electrode film without damaging the current collector and / or the dry electrode film.

[0132] Figures 8-10 This is a diagram of an apparatus for manufacturing electrodes for rechargeable lithium batteries according to an embodiment of the present disclosure.

[0133] refer to Figure 8 A current collector 200 with multiple protrusions is provided to unfold and move from the unfolding roller 1 of the current collector transfer unit. Transfer rollers 2, 3 and 4 are included to facilitate the transfer of the current collector 200.

[0134] The current collector 200 transferred from the spreading roller 1 passes through the current collector pressing units 310 (310A and 310B) located on two opposite surfaces of the current collector 200, and the movement of the current collector 200 is controlled by the floating roller 320. The movement of the current collector 200 can be stopped and adjusted along the floating roller 320, and a portion of the current collector 200 can be pressed by the current collector pressing units 310 (310A and 310B).

[0135] The current collector 200, which passes through the current collector pressing unit 310 (310A and 310B) and the floating roller 320, is laminated with the dry electrode film 230 that is unfolded from the unfolding rollers 5 and 6, and rolled by the dry electrode film rolling unit 330 (330A and 330B).

[0136] A portion of the current collector 200 passing between the dry electrode membrane rolling units 330 (330A and 330B) can be separated by the dry electrode membrane separation unit 340 (340A and 340B), thereby manufacturing Figure 7 Electrode III.

[0137] Although not in Figure 8 As shown, however, the apparatus for manufacturing electrodes may further include an adjustment unit for regulating the movement speed of the current collector in the current collector transfer unit, the current collector pressing unit, the dry electrode film rolling unit, and the dry electrode film removal unit, as well as the speed of the dry electrode film.

[0138] refer to Figure 9 The current collector 200, which has two surfaces with protrusions formed thereon, unfolds and moves from the unfolding roller 1 of the current collector transfer unit.

[0139] The current collector 200 transferred from the unfolding roller 1 passes between the laminating rollers 350 (350A and 350B), and the surface portions of the laminating rollers 350 (350A and 350B) located on the two surfaces of the current collector 200 protrude. When the laminating rollers 350 (350A and 350B) rotate, a region of the current collector 200 can be pressed down by the protruding portions.

[0140] The current collector 200 passes between laminating rollers 350 (350A and 350B) with partially protruding surfaces and is laminated onto the dry electrode film 230 unfolded from unfolding rollers 5 and 6 and rolled by dry electrode film rolling units 330 (330A and 330B).

[0141] A portion of the current collector 200 passing between the dry electrode membrane rolling units 330 (330A and 330B) can be separated by the dry electrode membrane separation unit 340 (340A and 340B), thereby manufacturing Figure 7 Electrode III.

[0142] Although not in Figure 9 As shown, however, the apparatus for manufacturing electrodes may further include an adjustment unit for regulating the movement speed of the current collector in the current collector transfer unit, the current collector pressing unit, the dry electrode film rolling unit, and the dry electrode film removal unit, as well as the speed of the dry electrode film.

[0143] refer to Figure 10The current collector 200, which has two surfaces with protrusions formed thereon, unfolds and moves from the unfolding roller 1 of the current collector transfer unit.

[0144] The current collector 200 transferred from the unfolding roller 1 passes through vertically movable laminating rollers 360 (360A and 360B) located on two opposite surfaces of the current collector 200. A region of the current collector 200 can be pressed by the vertical movement of the laminating rollers 360 (360A and 360B).

[0145] The current collector 200, which passes through vertically movable lamination rollers 360 (360A and 360B), is laminated onto the dry electrode film 230, which is unfolded from unfolding rollers 5 and 6, and rolled by dry electrode film rolling units 330 (330A and 330B).

[0146] A portion of the current collector 200 passing between the dry electrode membrane rolling units 330 (330A and 330B) can be separated by the dry electrode membrane separation unit 340 (340A and 340B), thereby manufacturing Figure 7 Electrode III.

[0147] Although not in Figure 10 As shown, however, the apparatus for manufacturing electrodes may further include an adjustment unit for regulating the movement speed of the current collector in the current collector transfer unit, the current collector pressing unit, the dry electrode film rolling unit, and the dry electrode film removal unit, as well as the speed of the dry electrode film.

[0148] Apparatus for manufacturing electrodes for rechargeable lithium batteries may further include a tab forming unit that forms tabs in a region (i.e., a second region) from which a dry electrode film is removed. The tab forming unit may include components that form tabs in uncoated portions.

[0149] Method for manufacturing electrodes for rechargeable lithium batteries

[0150] The following section describes a method for manufacturing electrodes for rechargeable lithium batteries.

[0151] The method of manufacturing the electrode may include: forming a plurality of protrusions on one entire surface or both surfaces of the current collector by the above-described plating (operation 1); pressing only the protrusions in a second region of the current collector (operation 2); laminating a dry electrode film onto one entire surface or both surfaces of the current collector, and then rolling the dry electrode film (operation 3); and removing only the dry electrode film corresponding to the second region (operation 4). In the method of manufacturing the electrode, the first region and the second region in which the protrusions are formed can be formed simultaneously by electroplating without patterning an adhesion-promoting layer, thereby improving manufacturability and reducing the possibility of damaging the electrode.

[0152] The plating can be performed using the method described above. According to the embodiment, the average height of the protrusions in the current collector can be 1.5 μm or higher, for example, in the range of 2 μm to 3 μm. In operation 2, as described above... Figures 8-10 The described current collector pressing unit is used to press the protrusions in the second region mentioned above.

[0153] Rechargeable lithium batteries

[0154] Another embodiment relates to a rechargeable lithium battery, wherein the rechargeable lithium battery includes electrodes according to embodiments of the present disclosure.

[0155] In a specific embodiment, the rechargeable lithium battery may include a positive electrode according to one embodiment and a negative electrode according to another embodiment. In another embodiment, the rechargeable lithium battery may include a positive electrode and a negative electrode according to one embodiment.

[0156] The negative electrode can be manufactured using a composition comprising the aforementioned negative electrode active material. The negative electrode active material is the same as described above. The composition may further comprise a binder and / or a conductive material. The negative electrode can be manufactured using a wet process. The binder and conductive material can be selected from common types known to those skilled in the art.

[0157] The positive electrode can be manufactured using a composition comprising the above-described positive electrode active material. The positive electrode active material is the same as described above. The composition may further comprise a binder and / or a conductive material. The positive electrode can be manufactured using a wet process. The binder and conductive material can be selected from common types known to those skilled in the art.

[0158] Rechargeable lithium batteries may further include an electrolyte. Electrolytes used in rechargeable lithium batteries include non-aqueous organic solvents and lithium salts.

[0159] Non-aqueous organic solvents are used as a medium through which ions involved in the electrochemical reactions of the battery can move. Non-aqueous organic solvents may include carbonate solvents, ester solvents, ether solvents, ketone solvents, alcohol solvents, aprotic solvents, or combinations thereof, and may be used alone or in combination of two or more.

[0160] In addition, when using carbonate solvents, cyclic carbonates and chain carbonates can be mixed and used.

[0161] In some types of rechargeable lithium-ion batteries, a separator is located between the positive and negative electrodes. The separator can be made of polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer separator comprising two or more of these layers.

[0162] The diaphragm may include a porous substrate and a coating comprising organic materials, inorganic materials or combinations thereof, and located on one or both surfaces of the porous substrate.

[0163] Organic materials may include polymers such as polyvinylidene fluoride or (meth)acrylic acid polymers.

[0164] Inorganic materials may include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof. However, this disclosure is not limited to these examples.

[0165] Organic and inorganic materials can be mixed and exist in a coating, or they can exist in the form of a coating that includes organic materials and a coating that includes inorganic materials laminated together.

[0166] Rechargeable lithium batteries can be cylindrical, prismatic, pouch-shaped, or coin-shaped, depending on their shape. Figures 11-14 This is a schematic diagram of a rechargeable lithium battery according to an embodiment, wherein... Figure 11 Explaining cylindrical batteries, Figure 12 Explaining the prismatic battery, and Figure 13 and Figure 14 Explaining pouch batteries. (Reference) Figures 11-14 The rechargeable lithium battery 100 may include an electrode assembly 40 (with a separator 30 inserted between a positive electrode 10 and a negative electrode 20) and a housing 50 in which the electrode assembly 40 is embedded. The positive electrode 10, negative electrode 20, and separator 30 may be impregnated with an electrolyte (not shown). Figure 11 As shown, the rechargeable lithium battery 100 may include a sealing member 60 of a sealed housing 50. Additionally, in Figure 12 In this context, the rechargeable lithium battery 100 may include a positive electrode lead connector 11, a positive electrode end 12, a negative electrode lead connector 21, and a negative electrode terminal 22. For example, in... Figure 13 and Figure 14 As shown, the rechargeable lithium battery 100 may include electrode terminals 70 (i.e., positive electrode terminal 71 and negative electrode terminal 72) that serve as electrical paths to guide the current generated in the electrode assembly 40 to the outside.

[0167] The rechargeable lithium batteries according to embodiments of this disclosure can be used in vehicles, mobile phones, and / or various types of electronic devices. However, this disclosure is not limited to these examples.

[0168] The aforementioned rechargeable lithium battery can be used to manufacture battery packs. A battery pack according to an embodiment of this disclosure includes a component in which individual batteries are electrically connected to each other and a battery pack housing housing the component. It may further include components such as busbars for electrical connections between the batteries, cooling units, and external terminals.

[0169] The battery pack can be installed in a vehicle. The vehicle can be, for example, an electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. The vehicle includes a four-wheeled vehicle or a two-wheeled vehicle. A vehicle according to an embodiment of this disclosure includes a battery pack according to an embodiment of this disclosure. According to one embodiment of this disclosure, the vehicle operates by receiving power from the battery pack.

[0170] The following describes embodiments and comparative examples of this disclosure. However, this disclosure is not limited to the embodiments and comparative examples described below.

[0171] Example 1

[0172] Manufacturing of dry electrode films

[0173] A mixture of 96.7 wt% artificial graphite and silicon-carbon composite as the negative electrode active material, 1.8 wt% PTFE as a binder, and 1.5 wt% carbon black as a conductive material was placed in a mixer and mixed at 10,000 rpm for 1 minute to obtain a mixture. Next, the obtained mixture was placed in a kneader and kneaded at 110°C and 60 rpm for 5 minutes to obtain a mixture agglomerate. The mixture agglomerate was placed in a mixer and pulverized at 14,000 rpm for 60 seconds to obtain electrode powder. Subsequently, the electrode powder was repeatedly pressed using a calendering roll (roll diameter: 200 mm and roll temperature: 70°C) to obtain a dry electrode film (thickness: 150 μm).

[0174] Manufacturing of current collectors with protrusions

[0175] The plating is used to form protrusions in the copper current collector. The average height of the protrusions is 2.5 μm.

[0176] Electrode manufacturing

[0177] Usage Reference Figure 10 The described apparatus prepares an electrode. A current collector with a width of 10 mm along its length is pressed between laminating rollers 360 (360A and 360B) heated to 75°C with a linear pressure of 0.5 tons / cm. A dry electrode film is laminated and rolled by dry electrode film rolling units 330 (330A and 330B), and the portion pressed by the laminating rollers 360 (360A and 360B) is removed to prepare the electrode.

[0178] Example 2

[0179] The electrode was prepared using essentially the same method as in Example 1, except that the current density was increased during the plating process in Example 1 to change the average height of the multiple protrusions of the copper current collector to 5.0 μm.

[0180] Example 3

[0181] The electrode was prepared using essentially the same method as in Example 1, except that the current density was increased during the plating process in Example 1 to change the average height of the multiple protrusions of the copper current collector to 3.0 μm.

[0182] Comparative Example 1

[0183] The electrode was prepared using essentially the same method as in Example 1, except that the current density was reduced in the plating of Example 1 to change the average height of the multiple protrusions of the copper current collector to 1.2 μm.

[0184] For the embodiments and comparative examples, the average height of the protrusions of the copper current collector after plating, the average height of the protrusions in the first region, and the average height of the protrusions in the second region are shown in Table 1 below.

[0185] In the first region, the adhesion between the copper current collector and the dry electrode film in the first region is evaluated in a 180° peel test. When fabricating the second region, it is determined whether the dry electrode film can be peeled off by hand ("O" indicates that it can be peeled off, "×" indicates that it cannot be peeled off).

[0186] Table 1

[0187]

[0188] As shown in Table 1 above, in the electrodes of the embodiments, the adhesion between the copper current collector and the dry electrode film is high, and there is no adhesion-promoting layer on the copper current collector. The formation of the uncoated portion is easy, and the manufacturability is excellent.

[0189] However, as shown in Table 1 above, when the average height of the protrusions in the first region is outside the scope of this disclosure, the adhesion between the copper current collector and the dry electrode film is not high.

[0190] According to this disclosure, the adhesion between the current collector and the dry electrode film is high, therefore, it is not necessary to form an adhesion-promoting layer on the current collector. According to this disclosure, uncoated portions can be easily formed in the electrode without patterning the current collector with an adhesion-promoting layer to form uncoated portions.

[0191] However, the effects achievable through this disclosure are not limited to those described above, and those skilled in the art will clearly understand from the following description of this disclosure other technical effects not described herein.

[0192] Although the invention has been described above with reference to limited examples and figures, it is not limited thereto, and various modifications and alterations can be made by those skilled in the art within the scope of the technical spirit of this disclosure.

Claims

1. An electrode for a rechargeable lithium battery, the electrode comprising: current collector; and A dry electrode film is provided in the region of the current collector. The region includes a plurality of protrusions extending from the current collector. The dry electrode film contacts the plurality of protrusions in the region, and The average height of the plurality of protrusions is greater than 1.0 μm.

2. The electrode of claim 1, wherein at least a portion of the dry electrode film in the region is located between the plurality of protrusions.

3. The electrode of claim 1, wherein the average spacing between the plurality of protrusions is 2.0 μm or less.

4. The electrode of claim 1, wherein the region does not contain an adhesion-promoting layer.

5. The electrode of claim 1, wherein the plurality of protrusions provide adhesion to the dry electrode film.

6. The electrode of claim 1, wherein the plurality of protrusions are formed on the current collector by plating.

7. The electrode of claim 1, wherein the region is a first region, and the current collector further includes a second region adjacent to the first region. Multiple protrusions extend from the current collector in the second region, and The dry electrode film is not provided in the second region.

8. The electrode of claim 7, wherein the average height of the plurality of protrusions in the second region is less than the average height of the plurality of protrusions in the first region.

9. The electrode of claim 8, wherein the average height of the plurality of protrusions in the second region is 2.0 μm or less.

10. The electrode of claim 7, wherein the plurality of protrusions in the first region and the plurality of protrusions in the second region are formed on the current collector by plating.

11. The electrode of claim 1, wherein the current collector is formed of copper foil. The dry electrode membrane comprises a negative electrode active material and a binder. The negative electrode active material includes at least one of carbon-based negative electrode active materials and Si-based negative electrode active materials, and the negative electrode active material has an average particle size D of 1 μm to 30 μm. 50 ,and The adhesive mentioned above includes polytetrafluoroethylene, polyolefins, or mixtures thereof.

12. An apparatus for manufacturing electrodes for rechargeable lithium batteries, the apparatus comprising: A current collector transfer unit is configured to transfer a current collector, the current collector including a plurality of protrusions extending from the current collector; A current collector pressing unit is configured to press a region of the current collector transferred from the current collector transfer unit; A dry electrode film rolling unit is configured to laminate a dry electrode film onto the current collector transferred from the current collector pressing unit and roll the dry electrode film. and A dry electrode film removal unit is configured to remove the dry electrode film corresponding to the pressed current collector in the laminate of the current collector and the dry electrode film transferred from the dry electrode film rolling unit.

13. The device of claim 12, wherein the plurality of protrusions of the current collector in the current collector transfer unit have an average height of 1.5 μm or higher.

14. The device of claim 12, wherein the current collector does not contain an adhesion promoting layer.

15. The apparatus of claim 12, wherein the current collector pressing unit comprises at least one of a pressing component including a floating roller, a laminating roller with a surface portion protruding, and a vertically movable laminating roller.

16. The device of claim 12, wherein the current collector pressing unit presses the current collector from the current collector transfer unit to press the average height of the plurality of protrusions of the current collector by 30% or less.

17. The apparatus of claim 12, wherein the dry electrode film rolling unit comprises a component configured to roll the dry electrode film at a temperature of 20°C to 150°C and a pressure of 0.01 ton / cm to 10 ton / cm.

18. The device of claim 12, wherein the dry electrode film removal unit comprises at least one of a brush, tape, vacuum suction device, ultrasonic generator, laser, and air knife.

19. The apparatus of claim 12, further comprising a tab forming unit configured to form a tab in the region from which the dry electrode film is removed.

20. A rechargeable lithium battery, comprising an electrode for a rechargeable lithium battery as claimed in any one of claims 1 to 11, or an electrode for a rechargeable lithium battery manufactured by the apparatus as claimed in any one of claims 12 to 19.

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