Electrode assembly, method for manufacturing an electrode assembly, and battery

Abstract

A cylindrical battery, an electrode assembly therein, and a method for manufacturing the electrode assembly are disclosed. The electrode assembly has a cylindrical shape formed by winding a stack multiple times to have a core, in which a separator is placed between a positive electrode and a negative electrode, and the electrode assembly includes a retaining strap configured to secure the separator exposed at the core to the inner surface of the electrode assembly.

Description

[0001] This application claims priority to Korean Patent Application No. 10-2024-0187806, filed on December 17, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to an electrode assembly and a battery including the electrode assembly. Background Technology

[0003] Unlike primary batteries, which are typically non-rechargeable, rechargeable batteries can usually be recharged and discharged. Low-capacity rechargeable batteries can be used in portable small electronic devices (such as smartphones, feature phones, laptops, digital cameras, and camcorders), while high-capacity rechargeable batteries are widely used as power sources, for example, to drive motors and store electrical energy in hybrid or electric vehicles. Such rechargeable batteries include electrodes containing positive and / or negative electrodes, electrode assemblies containing the electrodes, a housing that houses the electrode assemblies, and electrode terminals connected to the electrode assemblies.

[0004] With technological advancements, high-capacity batteries are advantageous. Therefore, multiple batteries can be electrically connected and used. For example, batteries can be applied to electronic devices in the form of battery modules comprising multiple batteries and / or battery packs comprising multiple battery modules. Battery packs, for example, are also constructed from multiple batteries. In this case, battery packs can be applied to electronic devices requiring high power and / or high capacity, including, for example, electric vehicles.

[0005] A battery includes electrode assemblies, which constitute a unit structure for performing charging and discharging operations. Electrode assemblies can be classified according to their shape as cylindrical electrode assemblies, stacked electrode assemblies, or stacked and folded electrode assemblies. Among these electrode assemblies, cylindrical electrode assemblies have the advantages of relatively large capacity and structural stability.

[0006] Cylindrical electrode assemblies can be manufactured into a core shape by repeatedly winding a stack of positive electrodes, diaphragms, negative electrodes, and diaphragms, each having an elongated sheet shape. During the winding process, the stack is wound multiple times in a clockwise or counterclockwise direction while a portion of the diaphragm is held in place. After the winding of the stack is complete, the held diaphragm is released, and a portion of the diaphragm is arranged in a yin-yang pattern intersecting with the core. The yin-yang pattern refers to a spiral pattern including interlocking curved regions. The diaphragm intersecting with the core becomes an obstacle in subsequent processes such as welding; therefore, a rewinding process is performed to bring the diaphragm intersecting with the core into contact or close contact with the inner surface of the electrode assembly.

[0007] The information disclosed above in the background section of this disclosure is intended only to improve the understanding of the background of this disclosure, and therefore may include information that does not form related technology. Summary of the Invention

[0008] This disclosure aims to provide an electrode assembly, a method for manufacturing the electrode assembly, and a battery including the electrode assembly, the battery being able to reduce or prevent the reforming separator in the cylindrical electrode assembly from detaching from the inner surface of the electrode assembly and intersecting with the core portion after the winding process.

[0009] However, the challenges to be addressed by this disclosure are not limited to the problems described above, and other challenges not mentioned will be clearly understood by those skilled in the art from the following description.

[0010] According to an example embodiment of the present disclosure, an electrode assembly having a cylindrical shape is formed by winding a stack multiple times to produce a core, the stack having a diaphragm disposed between a positive electrode and a negative electrode, the electrode assembly including a retaining band configured to secure the diaphragm exposed at the core to the inner surface of the electrode assembly.

[0011] According to one aspect of an example embodiment, the fixing strip may include an electrically insulating film. The electrically insulating film may be formed of or include at least one of polyimide (PI) resin, polyethylene (PE) resin, and polyester (PET) resin.

[0012] According to another aspect of the example embodiment, the fixing strip may include a porous membrane. The porous membrane may include a substrate membrane having a plurality of pores formed therein. Here, the area occupied by the plurality of pores may range from about 10% to about 90% of the area of ​​the substrate membrane. Furthermore, the plurality of pores may be substantially uniform in size and regularly arranged across the entire surface of the substrate membrane. Alternatively, the plurality of pores may be non-uniform in size or irregularly arranged across the entire surface of the substrate membrane. Additionally, the planar shape of each of the plurality of pores may be generally circular, elliptical, or polygonal.

[0013] According to another aspect of the exemplary embodiment, the fixing strap may include an upper fixing strap and a lower fixing strap, which are respectively attached to the upper and lower sides of the diaphragm to intersect with the end portions of the diaphragm. Additionally, the fixing strap may also include one or more intermediate fixing straps attached to the diaphragm between the upper and lower fixing straps.

[0014] According to another aspect of the example embodiment, the retaining strap may be attached along the end portion of the diaphragm.

[0015] According to another exemplary embodiment of this disclosure, a method for manufacturing an electrode assembly includes: preparing a stack with a diaphragm placed between a positive electrode and a negative electrode; clamping one end portion of the diaphragm and winding the stack multiple times to form an electrode assembly having a cylindrical shape; bringing the diaphragm exposed at the core of the electrode assembly into contact or close contact with the inner surface of the electrode assembly; and inserting a retaining strap into the core and securing the diaphragm in contact or close contact with the inner surface of the electrode assembly with the retaining strap.

[0016] According to one aspect of the example embodiment, the fixing strip may include an electrically insulating film.

[0017] According to another aspect of the example embodiment, the fixing strip may include a porous membrane. In this case, the porous membrane may include a substrate membrane having a plurality of pores formed therein, and the area occupied by the plurality of pores may range from about 10% to about 90% of the area of ​​the substrate membrane.

[0018] According to another aspect of the example embodiment, the fixing strap can be held by a clamp having a clip structure, or attached to a clamp having a suction function and inserted into the core.

[0019] According to another example embodiment of the present disclosure, the battery includes a cylindrical housing and an electrode assembly having a cylindrical shape, the electrode assembly being housed inside the cylindrical housing and formed by winding a stack multiple times to create a core, wherein a separator is placed between a positive electrode and a negative electrode, and the electrode assembly may include a retaining band configured to secure the separator exposed at the core of the electrode assembly to the inner surface of the electrode assembly.

[0020] According to one aspect of the example embodiment, the fixing strip may include an electrically insulating and porous membrane. In this case, the porous membrane may include a substrate membrane having a plurality of pores formed therein, and the area occupied by the plurality of pores may range from about 10% to about 90% of the area of ​​the substrate membrane. Attached Figure Description

[0021] The following accompanying drawings are intended to illustrate exemplary embodiments of this disclosure, and the spirit of this disclosure should be better understood through the drawings and the following description. Therefore, the illustrations in the drawings should not be construed as limiting the scope of this disclosure. In the drawings: Figure 1 It is a perspective view schematically showing the structure of the battery pack; Figure 2 It is shown schematically. Figure 1 A perspective view of the battery's structure; Figure 3 It is shown schematically. Figure 2 A cross-sectional view of the battery's structure; Figure 4This is a perspective view schematically illustrating the construction of an electrode assembly according to an example embodiment; Figure 5 It is shown schematically. Figure 4 A perspective view showing the electrode assembly and fixing strap separated; Figure 6 It is shown schematically. Figure 4 A plan view of the structure of the electrode assembly; Figure 7A This is a plan view schematically illustrating an example of a state where the retaining strip is only disposed on a portion of the inner surface of the electrode assembly; Figure 7B This is a plan view schematically illustrating another example of a state where the retaining band is only disposed on a portion of the inner surface of the electrode assembly; Figure 7C This is a plan view schematically illustrating yet another example of a state where the retaining band is only provided on a portion of the inner surface of the electrode assembly; Figure 8A This is a plan view schematically showing an example of a fixing band having multiple holes formed therein; Figure 8B This is a plan view schematically showing another example of a fixing band having multiple holes formed therein; Figure 8C This is a plan view schematically showing another example of a fixing band having multiple holes formed therein; Figure 9 This is a flowchart illustrating a method for manufacturing an electrode assembly according to an example embodiment; Figure 10 It is shown schematically in Figure 9 A diagram showing an example of the construction of a fixture that can be used in process S40; Figure 11A It is shown schematically in Figure 9 A diagram showing another example of the construction of a fixture that can be used in process S40; Figure 11B It is an illustrative representation of the use Figure 11A A diagram illustrating an example of the clamp holding the retaining strap; and Figure 11C It is an illustrative representation of the use Figure 11A The diagram shows another example of the clamp holding the fixing strap. Detailed Implementation

[0022] In the following, exemplary embodiments of this disclosure are 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 rather should be interpreted in a way consistent with the technical spirit of this disclosure, based on the principle that the inventors can appropriately define concepts and terms to best interpret the inventors' disclosure. Therefore, the constructions shown in the embodiments and drawings described herein are merely exemplary embodiments and do not represent the full technical spirit of this disclosure; thus, it should be understood that various equivalents and modifications can be made upon filing this application.

[0023] Furthermore, when used in this specification, "including / comprises" and / or variations thereof may indicate the presence of the described shapes, quantities, steps, operations, components, elements and / or groups thereof, and may not exclude the presence or addition of one or more other shapes, quantities, steps, operations, components, elements and / or groups thereof.

[0024] Furthermore, to aid in understanding the disclosure, the accompanying drawings may not be shown to scale. Instead, the dimensions of some components may be exaggerated. Additionally, the same reference numerals may be assigned to the same components in different embodiments.

[0025] A description of two objects being compared as "identical" can mean that they are "substantially identical." Therefore, the range for "substantially identical" can include cases with what is considered a low degree of deviation (e.g., within 5%). Additionally, a description of a specific parameter being identical in a specific region can mean that the parameter is identical from an average perspective.

[0026] Terms including ordinal numbers such as first and second can be used to describe various components; however, components are not limited by terms. These terms are only used to distinguish one component from another. Unless specifically described in the opposite way, the first component can also be the second component.

[0027] Throughout the manual, unless otherwise specifically stated, each component may be provided in the singular or plural.

[0028] The arrangement of any construction on the “upper part (or lower part)” of the component or on the “above (or below)” of the component can mean not only that any construction can be arranged to contact the upper surface (or lower surface) of the component, but also that another construction can be inserted between the component and any construction disposed on (or below) the component.

[0029] Additionally, when describing a component as “connected,” “combined,” or “accessible” to another component, these components may be “directly connected,” “directly combined,” or “directly accessed” by each other. However, it should be understood that another component may be “inserted” between these components, or these components may be “connected,” “combined,” or “accessible” through another component.

[0030] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of “may” refers to one or more embodiments of this disclosure. When preceding a column of elements, the terms “one or more” and “at least one” modify the entire column of elements, but not individual elements within that column.

[0031] Throughout this specification, unless otherwise stated, the expression "A and / or B" means A, B, or "A and B". Unless otherwise stated, the expression "C to D" means C or greater and D or less.

[0032] When phrases such as “at least one of A, B and C (species / beings)”, “at least one of A, B or C (species / beings)”, “at least one of A, B and C (species / beings)” or “selected from at least one of A, B and C (species / beings)” are used to specify 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.

[0033] As used herein, the term "use" and its variations may be considered synonymous with the term "utilize" and its variations, respectively. As used herein, the terms "substantially," "about," and similar terms are used as approximate terms rather than terms of degree and are intended to explain the inherent variations in measured or calculated values ​​that will be recognized by one of ordinary skill in the art. When a range is specified, the range includes all values ​​therebetween, such as increments of 0.1%.

[0034] It is understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, drawing layer, or section from another element, component, region, drawing layer, or section. Therefore, without departing from the teachings of the exemplary embodiments, the first element, first component, first region, first layer, or first portion discussed below may be referred to as a second element, second component, second region, second layer, or second portion.

[0035] For ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein to describe the relationship between one element or feature and another element(s) as shown in the accompanying drawings. It is understood that, in addition to the orientations depicted in the figures, the spatial relative terms are intended to cover different orientations of the device during use or operation. For example, when the device in the accompanying drawings is flipped, an element described as “below” or “under” other elements will subsequently be oriented “above” or “above” other elements. Thus, the term “below” can encompass both above and below orientations.

[0036] The terminology used in this specification is intended to describe exemplary embodiments of this disclosure and is not intended to limit this disclosure.

[0037] Figure 1 This is a perspective view schematically illustrating an example of the construction of a battery pack comprising multiple cylindrical cells. (See reference...) Figure 1 The battery pack includes a casing 1 and a battery 2.

[0038] The housing 1 forms the appearance of the battery pack and provides space to accommodate the battery 2. The housing 1 may include a housing body 11 and a cover 12.

[0039] The outer casing 11 may have a box shape with an empty interior and an open side. The cross-sectional shape of the outer casing 11 is not limited to... Figure 1 The quadrilateral shape shown can be modified in design to have various other shapes (such as polygonal shapes, circular shapes, and elliptical shapes).

[0040] The cover 12 can be attached to the housing body 11 and can close the internal space of the housing body 11. As an example, the cover 12 can have a generally plate shape and can face the opening side of the housing body 11. The cover 12 can be fixed to the housing body 11 by various types of attachment methods (such as bolting, welding, assembly, etc.).

[0041] Battery 2 can form a unit structure for storing and supplying power within a battery pack. Multiple batteries 2 can be arranged. Multiple batteries 2 can be arranged within the casing 1 to form various patterns (such as grid shapes and zigzag shapes, for example). Multiple batteries 2 can be arranged side-by-side. The number of batteries 2 can be varied in design depending on the size, shape, etc., of the casing 1. The detailed construction of each battery 2 is described below.

[0042] Multiple batteries 2 can be electrically connected via, for example, a busbar (not shown). Multiple batteries 2 can be connected in series or in parallel via the busbar. As an example, in the housing 1, the busbar can connect batteries 2 arranged in the same row in parallel and batteries 2 arranged in two adjacent rows in series. The busbar can be formed of or include at least one conductive material such as copper, aluminum, nickel, etc.

[0043] Figure 2 It is a perspective view schematically illustrating the construction of a battery according to an example embodiment, and Figure 3 It is shown schematically. Figure 2 A cross-sectional view of the battery's structure. (Refer to...) Figure 2 and Figure 3 The battery 2 may include a housing 100, an electrode assembly 200, and a cover assembly 300.

[0044] The housing 100 can form the schematic appearance of the battery 2. The housing 100 can be formed of or include a conductive material. For example, the housing 100 can be formed of or include a material comprising at least one of steel, stainless steel, aluminum, and aluminum alloys. Therefore, the housing 100 can protect the electrode assembly 200 from external impacts and can be configured to perform a heat dissipation function to release the heat generated during the charging and discharging operation of the electrode assembly 200 to the outside of the housing 100.

[0045] The housing 100 may include a sidewall portion 110, which is cylindrical in shape and has a central axis C formed in the central portion. The central axis C of the housing 100 described below may refer to the central axis of the sidewall portion 110. The two end portions of the sidewall portion 110 perpendicular to the central axis C of the housing 100 may be open.

[0046] The housing 100 may further include a bottom portion 120 that encloses the lower end portion of the sidewall portion 110. The bottom portion 120 may have a generally disc-shaped form and may be positioned facing the lower end portion of the sidewall portion 110. The bottom portion 120 may be positioned perpendicular to the central axis C of the housing 100. The peripheral surface of the bottom portion 120 may be bonded to the lower end portion of the sidewall portion 110. The bottom portion 120 may be integrally formed with the sidewall portion 110 by a drawing process or the like, or alternatively, the bottom portion 120 may be manufactured separately from the sidewall portion 110 and then bonded to the sidewall portion 110 by welding or the like.

[0047] The housing 100 may also include an opening 130 that opens the upper portion of the sidewall portion 110. The opening 130 may be configured to provide a path and space in the upper region of the housing 100 through which the electrode assembly 200, described below, is inserted into the interior of the housing 100, and in which the cover assembly 300, described below, can be mounted. The opening 130 may refer to an empty space located on the side opposite the bottom portion 120 and surrounded by the upper region of the sidewall portion 110.

[0048] The electrode assembly 200 can be configured as a unit structure for performing charging and discharging operations in the battery 2. The electrode assembly 200 may include a first electrode plate 210, a second electrode plate 220, and a separator 230 disposed between the first electrode plate 210 and the second electrode plate 220.

[0049] The electrode assembly 200 can be disposed inside the housing 100. The electrode assembly 200 can be inserted into the housing 100 through the opening 130 of the housing 100.

[0050] The electrode assembly 200 can have a shape that is wound around a winding axis. For example, the electrode assembly 200 can have a shape in which a first electrode plate 210, a diaphragm 230, and a second electrode plate 220 are stacked and wound around a winding axis in a clockwise or counterclockwise direction. Therefore, the electrode assembly 200 can have a shape that is substantially similar to that of an electrode core (cylindrical shape). Here, the winding axis can refer to a straight line passing through the central portion of the electrode assembly 200. The winding axis of the electrode assembly 200 can be configured to be coaxial with the central axis C of the housing 100.

[0051] The first electrode plate 210 can constitute the positive electrode of the electrode assembly 200. The first electrode plate 210 can be formed in the shape of a foil containing a metallic material such as aluminum or an aluminum alloy. The type, size, and shape of the first electrode plate 210 are not particularly limited, as long as the first electrode plate 210 is conductive and does not cause adverse chemical changes in the battery.

[0052] The first active material layer may be applied to at least a portion of the first electrode plate 210. The first active material layer may be applied to both surfaces of the first electrode plate 210, or alternatively, it may be applied to only one surface of the first electrode plate 210. Since the first electrode plate 210 constitutes a positive electrode, the first active material layer may include a positive electrode active material.

[0053] Positive electrode active materials may include compounds capable of reversibly inserting and deintercalating lithium (lithiation intercalation compounds). For example, positive electrode active materials may include one or more types of composite oxides of lithium with at least one metal such as or including cobalt, manganese, nickel, iron, and combinations thereof.

[0054] For example, the positive electrode active material may include at least one of lithium iron phosphate (LiFePO4, LFP), lithium manganese iron phosphate (LiMnFePO4, LMFP), and lithium nickel cobalt manganese oxide (LiNi x Co y Mn z O2, NCM). For example, the conditions 0 < x < 1, 0 < y < 1, 0 < z < 1 and x + y + z = 1 may be satisfied. The positive electrode active material may include only one of LiFePO4, LiMnFePO4, and LiNi x Co y Mn z O2, and may also include two or all of LiFePO4, LiMnFePO4, and LiNi x Co y Mn z O2.

[0055] The first active material layer may further include a positive electrode conductive material. The positive electrode conductive material is included to impart conductivity to the first active material layer, and may include any conductive material that does not cause a chemical change in the battery. Examples of the positive electrode conductive material may include: carbon-based materials, such as at least one of natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanofiber, carbon nanotube, etc.; metal-based materials, in the form of metal powder or metal fiber, including at least one of copper, nickel, aluminum, silver, etc.; conductive polymers, such as polyphenylene derivatives; or mixtures thereof.

[0056] The first active material layer may further include a positive electrode binder. The positive electrode binder is configured to adhere the particles constituting the positive electrode active material to each other and to adhere the positive electrode active material to the first electrode plate 210. Examples of the positive electrode binder may include at least one of non-aqueous binders, aqueous binders, dry binders, and combinations thereof.

[0057] The non-aqueous binder may include at least one of polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamideimide, polyimide, and combinations thereof.

[0058] The aqueous binder may be or include at least one of styrene-butadiene rubber, (meth)acrylic esterified styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluororubber, polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphazene, poly(meth)acrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0059] When an aqueous binder is included as the positive electrode binder, a cellulose compound capable of imparting viscosity may be further included. As a cellulose compound, one or more of carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, and their alkali metal salts may be combined. At least one of Na, K, and Li may be included as an alkali metal.

[0060] Dry adhesives are polymeric materials capable of being fibrous, and may be or include at least one of, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, and combinations thereof.

[0061] The first electrode plate 210 can be electrically connected to the cover assembly 300. Since the first electrode plate 210 constitutes the positive electrode of the electrode assembly 200, the cover assembly 300 can constitute the positive terminal of the battery 2. As an example, the first electrode plate 210 can be electrically connected to the cover assembly 300 via a first electrode connector E1. The first electrode connector E1 can include a conductive metallic material such as at least one of copper, copper alloy, nickel, and nickel alloy. The first electrode connector E1 is disposed on the upper side of the electrode assembly 200 and can have two end portions respectively connected to the first electrode plate 210 and the cover assembly 300. One end portion of the first electrode connector E1 can be directly connected to the first electrode plate 210, or indirectly connected to the first electrode plate 210 via a separate current collector (not shown) connected to the first electrode plate 210. However, the first electrode plate 210 is not limited to the above situations and can also be directly connected to the cover assembly 300 without the first electrode connector E1.

[0062] The second electrode plate 220 can constitute the negative electrode of the second electrode assembly 200. The second electrode plate 220 can be in the form of a foil comprising or containing at least one of a metallic material such as copper, a copper alloy, nickel, and a nickel alloy. The second electrode plate 220 can be spaced apart from the first electrode plate 210 by a desired or predetermined interval, facing the first electrode plate 210. There are no particular limitations on the type, size, and shape of the second electrode plate 220, as long as it is conductive and does not cause adverse chemical changes in the battery.

[0063] The second active material layer may be applied to at least a portion of the second electrode plate 220. The second active material layer may be applied to both surfaces of the second electrode plate 220, or alternatively, it may be applied to only one surface. Since the second electrode plate 220 constitutes a negative electrode, the second active material layer may include a negative electrode active material.

[0064] The negative electrode active material may include at least one of a material capable of reversibly inserting / extracting lithium ions, lithium metal, a lithium metal alloy, a material capable of doping and dedoping lithium, and a transition metal oxide.

[0065] The material capable of reversibly inserting and extracting lithium ions is a carbon-based negative electrode active material and may include, for example, crystalline carbon, amorphous carbon, and combinations thereof. Examples of crystalline carbon may include graphite, such as natural graphite or artificial graphite in the form of non-fixed shapes, plates, flakes, spheres, or fibers. Examples of amorphous carbon may include at least one of soft carbon, hard carbon, mesophase pitch carbonization products, calcined coke, etc.

[0066] The lithium metal alloy may be or include an alloy of lithium and a metal (such as at least one of Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al, and Sn).

[0067] A Si-based negative electrode active material or a Sn-based negative electrode active material may be included as a material capable of doping and dedoping lithium. The Si-based negative electrode active material may include silicon, a silicon-carbon composite, SiO x (0 < x ≤ 2), a Si-Q alloy (where Q is or includes at least one of an alkali metal, an alkaline earth metal, a Group 13 element, a Group 14 element (excluding Si), a Group 15 element, a Group 16 element, a transition metal, a rare earth element, and combinations thereof), and combinations thereof. The Sn-based negative electrode active material may be or include at least one of Sn, SnO2, a Sn-based alloy, and combinations thereof.

[0068] The silicon-carbon composite may be or include a composite of silicon and amorphous carbon. According to one exemplary embodiment, the silicon-carbon composite may be in the form of silicon particles and an amorphous carbon coating on the surface of the silicon particles. For example, the silicon-carbon composite may include secondary particles (cores) in which silicon primary particles agglomerate and an amorphous carbon coating layer (shells) on the surface of the secondary particles. Amorphous carbon may also be located between the silicon primary particles such that, for example, the silicon primary particles are coated with amorphous carbon. The secondary particles may be dispersed in an amorphous carbon matrix.

[0069] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core containing crystalline carbon and silicon particles and an amorphous carbon coating layer on the surface of the core.

[0070] The Si-based negative electrode active material or the Sn-based negative electrode active material may be included by mixing with the carbon-based negative electrode active material.

[0071] The second active material layer may further include a negative electrode conductive material and a negative electrode binder.

[0072] The battery includes a negative electrode conductive material to impart conductivity to the second active material layer, and may include any conductive material that does not cause chemical changes in the battery. Examples of negative electrode conductive materials may include: carbon-based materials, such as at least one of natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanofiber, carbon nanotube, etc.; metallic materials, in the form of metal powder or metal fiber, including at least one of copper, nickel, aluminum, silver, etc.; conductive polymers, such as polyphenylene derivatives; or mixtures thereof.

[0073] The negative electrode binder is configured to adhere the particles constituting the negative electrode active material to each other and to adhere the negative electrode active material to the second electrode plate 220. Examples of negative electrode binders may include at least one of non-aqueous binders, aqueous binders, dry binders, and combinations thereof.

[0074] Non-aqueous adhesives may include at least one of polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene-propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide-imide, polyimide, and combinations thereof.

[0075] The waterborne adhesive may be or include at least one of styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluororubber, polyethylene oxide, polyvinylpyrrolidone, polyepoxygenated alcohol, polyphosphazene, poly(meth)acrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0076] When an aqueous binder is included as the negative electrode binder, a cellulose compound capable of imparting viscosity may be further included. As a cellulose compound, one or more of carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, and their alkali metal salts may be combined. At least one of Na, K, and Li may be included as an alkali metal.

[0077] Dry adhesives are polymeric materials capable of being fibrous, and may be or include at least one of, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, and combinations thereof.

[0078] The second electrode plate 220 can be electrically connected to the housing 100. As an example, the second electrode plate 220 can be electrically connected to the housing 100 via a second electrode connector E2. Since the second electrode plate 220 constitutes the negative electrode of the electrode assembly 200, the housing 100 can constitute the negative terminal of the battery 2. The second electrode connector E2 can be formed of or include at least one conductive metal material such as copper, copper alloy, nickel, and nickel alloy. The second electrode connector E2 is disposed on the lower side of the electrode assembly 200 and can have two end portions respectively connected to the second electrode plate 220 and the bottom portion 120 of the housing 100. One end portion of the second electrode connector E2 can be directly connected to the second electrode plate 220, or indirectly connected to the second electrode plate 220 via a separate current collector (not shown) connected to the second electrode plate 220. However, the second electrode plate 220 is not limited to the above, and can also be directly connected to the housing 100 without the second electrode connector E2.

[0079] A diaphragm 230 may be disposed between the first electrode plate 210 and the second electrode plate 220. The diaphragm 230 may be configured to reduce or prevent short circuits between the first electrode plate 210 and the second electrode plate 220 while allowing lithium ions to move between them.

[0080] The diaphragm 230 may include at least one of polyethylene, polypropylene, polyvinylidene fluoride, and multilayer membranes of the same type with two or more layers, and may also include mixed multilayer membranes such as polyethylene / polypropylene bilayer membranes, polyethylene / polypropylene / polyethylene trilayer membranes, polypropylene / polyethylene / polypropylene trilayer membranes, etc.

[0081] The diaphragm 230 may include a porous substrate and a coating layer, comprising organic materials, inorganic materials, or combinations thereof, positioned on one or both surfaces of the porous substrate.

[0082] The porous substrate may be or include at least one of the following polymers or copolymers or mixtures thereof: polyolefins (such as polyethylene, polypropylene, etc.), polyesters (such as polyethylene terephthalate, polybutylene terephthalate, etc.), polyacetal, polyamide, polyimide, polycarbonate, polyetheretherketone, polyaryletherketone, polyetherimide, polyamideimide, polybenzimidazole, polyethersulfone, polyphenylene ether, cyclic olefin copolymers, polyphenylene sulfide, polyethylene naphthalate, glass fiber, Teflon, and polytetrafluoroethylene.

[0083] Organic materials may include polymers such as polyvinylidene fluoride or (meth)acrylic acid polymers.

[0084] Inorganic materials may include inorganic particles such as or containing at least one of Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but this disclosure is not limited thereto.

[0085] Organic and inorganic materials can be mixed in a single coating layer, or they can exist in the form of a coating layer including organic materials and a coating layer including inorganic materials stacked together.

[0086] A pair of diaphragms 230 can be provided. The pair of diaphragms 230 can respectively face the opposing surfaces of the first electrode plate 210 or the second electrode plate 220. The pair of diaphragms 230 can be wound together with the first electrode plate 210 and the second electrode plate 220 around a winding shaft.

[0087] The first insulating plate 201 and the second insulating plate 202 can be respectively disposed on both sides of the electrode assembly 200. Figure 3 The upper and lower sides of the first insulating plate 201 and the second insulating plate 202 may each include an insulating material (such as rubber, polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), etc.).

[0088] The first insulating plate 201 may have a generally disc-shaped form. The first insulating plate 201 may be disposed between the upper surfaces of the cover assembly 300 and the electrode assembly 200. Therefore, the first insulating plate 201 can substantially prevent the upper surface of the electrode assembly 200 from directly contacting the cover assembly 300, and substantially insulate the electrode assembly 200 and the cover assembly 300 from each other. A through-hole (not shown) through which the first electrode contact E1 can pass may be formed in the first insulating plate 201.

[0089] The second insulating plate 202 may have a generally disc-shaped form. The second insulating plate 202 may be disposed between the lower surface of the electrode assembly 200 and the bottom portion 120 of the housing 100. Therefore, the second insulating plate 202 can substantially prevent the lower surface of the electrode assembly 200 from directly contacting the bottom portion 120 of the housing 100, and substantially insulate the electrode assembly 200 and the bottom portion 120 of the housing 100 from each other. A through-hole (not shown) through which the second electrode contact E2 can pass may be formed in the second insulating plate 202.

[0090] The cover assembly 300 may be disposed at the upper end portion of the side wall portion 110, that is, at the opening 130. The opening 130 of the housing 100 is sealed by the cover assembly 300, for which the cover assembly 300 may be attached to the housing 100.

[0091] A rolled edge 140, recessed toward the central axis C of the housing 100, can be formed on the side wall portion 110. The rolled edge 140 is provided on the underside of the cover assembly 300 and can limit the insertion of the cover assembly 300 into the housing 100 by a predetermined distance.

[0092] A crimping portion 150, formed by bending the upper end portion of the sidewall portion 110 toward the central axis C of the housing 100, can be formed on the upper side of the rolled edge portion 140. The crimping portion 150 is provided on the upper side of the cover assembly 300 and can substantially prevent the cover assembly 300 from separating from the housing 100.

[0093] Gasket G may be disposed between housing 100 and cover assembly 300. Gasket G may be configured to fix the position of cover assembly 300 in opening 130 by its own elastic restoring force, electrically insulate housing 100 and cover assembly 300 from each other, and substantially prevent moisture or electrolyte from entering or leaving between housing 100 and cover assembly 300.

[0094] The gasket G may comprise an insulating material such as at least one of rubber, polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), etc. The gasket G may have a generally ring shape and may be disposed inside the crimped portion 140 and / or the crimped portion 150. The outer surface of the gasket G may contact or be in close contact with the inner surface of the crimped portion 140 and / or the crimped portion 150, and the inner surface of the gasket G may contact or be in close contact with the outer surface of the cover assembly 300.

[0095] As described above, the cover assembly 300 can be electrically connected to the first electrode plate 210 via the first electrode terminal E1. Since the first electrode plate 210 constitutes the positive electrode of the electrode assembly 200, the cover assembly 300 can constitute the positive terminal of the battery.

[0096] The cover assembly 300 may be configured to interrupt current flow when the internal pressure of the housing 100 increases due to overcurrent, thereby cutting off the electrical connection between the battery 2 and the external device. The cover assembly 300 may also be configured to rupture when the internal pressure of the housing 100 increases to a level greater than or equal to a set level, while allowing communication between the internal and external spaces of the housing 100. Therefore, the cover assembly 300 can reduce the risk of battery 2 exploding in the event of an overcurrent.

[0097] Figure 4 This is a perspective view schematically illustrating the construction of an electrode assembly according to an example embodiment. Figure 5 It is shown schematically. Figure 4 A perspective view showing the electrode assembly and fixing strap separated, and Figure 6 It is shown schematically. Figure 4A plan view of the structure of the electrode assembly.

[0098] Reference Figures 4 to 6 The electrode assembly 200 is a cylindrical electrode assembly formed by winding a stack multiple times, in which the positive electrode 210, the diaphragm 230, the negative electrode 220, and the diaphragm 230 are stacked (e.g., stacked sequentially). This type of electrode assembly is also commonly referred to as a core electrode assembly.

[0099] The positive electrode 210, negative electrode 220, and separator 230 may have a sheet shape with a relatively long side. The term "sheet shape" can refer to a structure with substantially uniform thickness and a generally rectangular planar shape. The length of the short side can vary depending on the height of the battery including the electrode assembly 200. Additionally, the length of the long side can vary depending on the number of turns of the stack constituting the electrode assembly 200. Typically, among the positive electrode 210, negative electrode 220, and separator 230, the separator 230 has the longest length along its long side.

[0100] The cylindrical electrode assembly 200 can be manufactured by alternately stacking sheet-like positive electrodes 210, sheet-like diaphragms 230, sheet-like negative electrodes 220, and sheet-like diaphragms 230 to form a stack, and then winding the stack multiple times while clamping the remaining portion of the diaphragm 230 protruding in the longitudinal direction beyond the positive electrode 210 or negative electrode 220 with a rod-shaped winding member. In this case, the rod-shaped winding member can serve as the winding axis of the electrode assembly 200, and the winding axis can be substantially parallel to the short side of the diaphragm 230. Additionally, when the electrode assembly 200 is inserted into the housing 100, the winding axis can be aligned with the central axis C of the housing (see...). Figure 3 They are basically parallel.

[0101] When the rod-shaped core member is removed after the stacked body is wound, the central portion (core portion A) of the electrode assembly 200 becomes hollow. However, the remaining portion of the diaphragm 230, held by the rod-shaped core member, intersects with core portion A, and the diaphragm 230 with the remaining portion intersecting with core portion A can form a planar shape resembling a yin-yang symbol. Subsequently, a reforming process is performed by inserting a reforming pin into core portion A to tightly attach the remaining portion of the diaphragm 230 to the inner surface of the electrode assembly 200. As a result, core portion A of the electrode assembly 200 no longer has any remaining portion of the diaphragm 230 and remains hollow.

[0102] According to an example embodiment, the electrode assembly 200 further includes a retaining band 240 configured to secure the reformed diaphragm 230 to the inner surface of the electrode assembly 200. The retaining band 240 is configured to secure the remaining portion of the diaphragm 230 that has come into contact or close contact with the inner surface of the electrode assembly 200 during the reforming process, preventing it from detaching. In other words, the retaining band 240 substantially prevents the remaining portion of the diaphragm 230 from detaching from the inner surface of the electrode assembly 200 and protruding toward the core portion A after the reforming process.

[0103] Therefore, subsequent processes (such as the welding process for electrode terminals) can substantially prevent the diaphragm 230 from being damaged by the welding rod. Furthermore, during the electrolyte injection process, the collapse of the diaphragm 230 can also be substantially prevented. As a result, not only is the productivity of the electrode assembly 200 improved, but the stability of the electrode assembly 200 is also enhanced.

[0104] The retaining tape 240 may include an electrically insulating film. For example, the retaining tape 240 may have a configuration in which an adhesive is applied to a surface of the electrically insulating film or an adhesive layer is attached to that surface. Therefore, the retaining tape 240 may reduce or prevent current leakage in the core portion A of the electrode assembly 200.

[0105] There are no particular limitations on the materials used for the electrically insulating film. For example, the electrically insulating film can be formed from or include polyimide (PI) resins, polyethylene (PE) resins, polyester (PET) resins, etc. However, this disclosure is not limited to this, and the electrically insulating film can also be formed from or include materials such as polyolefin resins, polyvinyl chloride resins, ethylene-vinyl acetate (EVA) resins, and silicone rubber.

[0106] According to one example embodiment, the electrically insulating membrane may be formed of or comprise a material that does not react with the electrolyte of the battery 2. Therefore, even when the electrolyte is injected into the interior of the housing 100 of the battery 2 and the electrode assembly 200 is immersed in the electrolyte, the retaining strap 240 can continuously reduce or prevent the separator 230 from detaching.

[0107] The retaining band 240 may have a shape that wraps around the entire inner surface of the electrode assembly 200. More specifically, the retaining band 240 may have an integral cylindrical shape (see...). Figure 5 Additionally, a cylindrical fixing strap 240 is provided at the core portion A of the electrode assembly 200, and can fix the diaphragm 230 to the entire inner surface of the electrode assembly 200. For example, the height of the fixing strap 240 can be less than or equal to the width of the diaphragm 230.

[0108] Alternatively, the retaining band 240 may be disposed only on a portion of the inner surface of the electrode assembly 200. In this case, the retaining band 240 may be attached across the end portion of the diaphragm 230 exposed in the core portion A of the electrode assembly 200, effectively preventing the diaphragm 230 from detaching again. Furthermore, since the retaining band 240 only covers a portion of the diaphragm 230, any reduction or unevenness in the impregnation rate of the electrode assembly 200 caused by the retaining band 240 during the subsequent electrolyte injection process can be reduced or minimized.

[0109] Figures 7A to 7C Each is a plan view schematically showing the state in which the fixing strip is only set on a portion of the inner surface of the electrode assembly. Figures 7A to 7C The inner surface of the electrode assembly, as shown schematically and viewed from the core portion of the electrode assembly, is illustrated. Figures 7A to 7C In the diagram, the vertical line L can correspond to the outline of one end portion of the diaphragm 230 (i.e., one short side of the diaphragm 230).

[0110] Reference Figure 7A The retaining band 240a may include an upper retaining band 240a1 and a lower retaining band 240a2 attached to the inner surface of the electrode assembly 200 (e.g., diaphragm 230). Both the upper retaining band 240a1 and the lower retaining band 240a2 may be attached to the diaphragm 230 exposed in the core portion while passing through a short side L of the diaphragm 230 in a horizontal direction. This effectively reduces or prevents one end portion of the diaphragm 230 from detaching from the inner surface of the electrode assembly 200.

[0111] The upper fixing band 240a1 is attached to the upper side of the diaphragm 230. The upper fixing band 240a1 can be attached aligned with the upper end of the diaphragm 230, or it can be attached slightly below the upper end. Additionally, the lower fixing band 240a2 is attached to the lower side of the diaphragm 230. The lower fixing band 240a2 can be attached aligned with the lower end of the diaphragm 230, or it can be attached slightly above the lower end.

[0112] According to the example embodiment, by reducing or minimizing the area occupied by the fixing tape 240a used to fix the diaphragm 230, the reduction in impregnation performance caused by the insertion of the fixing tape 240a can be reduced or minimized. On the other hand, since the fixing tape 240a can fix the diaphragm 230 at least on the upper and lower sides by passing through the short side L, the fixing tape 240a can provide the lower or minimum adhesive force required to fix the diaphragm 230.

[0113] Reference Figure 7BThe fixing band 240b may include an upper fixing band 240b1, a lower fixing band 240b2, and a middle fixing band 240b3 attached to the inner surface of the electrode assembly 200 (e.g., diaphragm 230). Furthermore, the upper fixing band 240b1, lower fixing band 240b2, and middle fixing band 240b3 may all be attached to the diaphragm 230 exposed in the core portion by passing horizontally through a short side L of the diaphragm 230. This further effectively reduces or prevents one end portion of the diaphragm 230 from detaching from the inner surface of the electrode assembly 200.

[0114] An upper fixing band 240b1 is attached to the upper side of the diaphragm 230. The upper fixing band 240b1 can be attached aligned with the upper end of the diaphragm 230, or it can be attached slightly below the upper end. A lower fixing band 240b2 is attached to the lower side of the diaphragm 230. The lower fixing band 240b2 can be attached aligned with the lower end of the diaphragm 230, or it can be attached slightly above the lower end. A middle fixing band 240b3 is attached to the diaphragm 230 between the upper fixing band 240b1 and the lower fixing band 240b2.

[0115] According to the example embodiment, by minimizing or reducing the area occupied by the fixing band 240b for securing the diaphragm 230, the reduction in impregnation performance caused by the insertion of the fixing band 240b can be reduced or suppressed. On the other hand, since the fixing band 240b can secure the diaphragm 230 not only at the upper and lower sides but also at the middle side while intersecting at least the short side L of the diaphragm 230, the adhesive force required to secure the diaphragm 230 provided by the fixing band 240b can be further enhanced.

[0116] Reference Figure 7C The retaining tape 240c can be attached to the diaphragm 230 exposed in the core portion, substantially parallel to one short side L of the diaphragm 230. That is, the retaining tape 240c can be attached vertically while covering one short side L of the diaphragm 230. Figure 7C In the diagram, the retaining band 240c is shown as a single piece, but it can be divided into multiple pieces and attached along a short side L of the diaphragm 230. This effectively prevents one end portion of the diaphragm 230 from detaching from the inner surface of the electrode assembly 200.

[0117] According to the example embodiment, by reducing or minimizing the area occupied by the fixing strap 240c used to fix the diaphragm 230, the reduction in impregnation performance caused by the insertion of the fixing strap 240c can be reduced or minimized. Furthermore, since the fixing strap 240c can fix the diaphragm 230 while covering most of the short side L of the diaphragm 230, the end portion of the diaphragm 230 can be more securely fixed.

[0118] Continue to refer to Figure 5The fixing band 240 may include a porous membrane. When the fixing band 240 is formed of or includes a porous membrane, electrolyte can pass through the pores H of the fixing band 240, thereby reducing or suppressing the reduction of electrolyte impregnation caused by the fixing band 240. However, this disclosure is not limited thereto, and the fixing band 240 may be a conventional band in which no pores are formed.

[0119] A porous membrane can refer to a structure having a substrate membrane in which multiple pores H are formed. Here, pores H can be through-holes that penetrate the substrate membrane. There are no particular limitations on the size of pores H, and they can have a size that allows electrolytes to pass through or a larger size.

[0120] Considering the impregnation characteristics of the electrolyte, it is advantageous for the pores H formed in the fixing tape 240 to be as large as possible and to be formed in large quantities. However, when the pores H are too large or exist in large quantities, the adhesive force of the fixing tape 240 may be insufficient. With this in mind, the area occupied by the multiple pores H can be in the range of about 10% to about 90% of the area of ​​the fixing tape 240.

[0121] Figures 8A to 8C It is a schematic plan view showing the form of the fixing bands, each fixing band having multiple holes formed therein.

[0122] Reference Figures 8A to 8C Multiple holes H1, H2, or H3 can be arranged (e.g., regularly) on the entire surface of the fixing belt 240. There are no particular limitations on the regular arrangement, and the multiple holes H1, H2, or H3 can be arranged in rows in the horizontal and / or vertical directions, or in a zigzag pattern in the horizontal or vertical directions. Alternatively, the multiple holes H1, H2, or H3 can be arranged substantially randomly on the entire surface of the fixing belt 240.

[0123] There are no particular restrictions on the planar shape of each of the plurality of holes H1, H2, and H3. For example, each or at least one of the plurality of holes H1, H2, and H3 may have a circular shape, an elliptical shape, a rectangular shape, a triangular shape, or other polygonal shape. In addition, the dimensions of the plurality of holes H1, H2, or H3 may be substantially uniform or vary across the entire fixing band.

[0124] Next, a method for manufacturing an electrode assembly according to an example embodiment will be described.

[0125] Figure 9 This is a flowchart illustrating a method for manufacturing an electrode assembly according to an example embodiment.

[0126] Reference Figures 4 to 6 and Figure 9First, a stack body with a diaphragm inserted between the positive and negative electrodes is prepared (S10). The stack body may include, for example, sheet-like positive electrode 210, sheet-like diaphragm 230, sheet-like negative electrode 220, and sheet-like diaphragm 230 stacked together (e.g., stacked alternately). In addition, in the stack body, the length of the long side of the diaphragm 230 may be greater than the length of the positive electrode 210 and the negative electrode 220, so at least one side of the diaphragm 230 may include a remaining portion having a predetermined or desired length (i.e., a portion protruding outward from one side of the positive electrode 210 and the negative electrode 220).

[0127] Additionally, within the stack, one end portion (i.e., the remaining portion) of the diaphragm 230 is clamped, and the stack is wound multiple times (S20). As a result of the winding process (S20), a core electrode assembly (i.e., a cylindrical electrode assembly) is manufactured. In the winding process (S20), there are no particular limitations on the type of winding member included for clamping one end portion of the diaphragm 230. Furthermore, there are no particular limitations on the number of windings performed in the winding process (S20), and they can vary depending on the size or performance of the core electrode assembly to be manufactured. After performing the winding process (S20), the diaphragm is removed from the winding member.

[0128] In addition, a reshaping process (S30) is performed on the electrode assembly wound into a cylindrical shape. More specifically, the diaphragm 230 exposed at the core of the cylindrical wound electrode assembly is brought into contact or close contact with the inner surface of the electrode assembly. As a result, the core becomes an empty space with nothing inside.

[0129] Additionally, a retaining strap 240 is inserted into the empty core to secure the diaphragm 230, which is in contact or close contact with the inner surface of the electrode assembly, using the retaining strap 240 (S40). At this time, the retaining strap 240 is attached to cover part or all of the end portion of the diaphragm 230 (i.e., the short side of the diaphragm 230 exposed at the core), thereby substantially preventing the attached diaphragm 230 from subsequently detaching and protruding into the core. The dimensions, shape, arrangement, and porous structure of the retaining strap 240 have been described in detail above; therefore, further description of it is omitted here.

[0130] According to an example embodiment, the process of attaching the fixing tape 240 in process S40 can be performed using a predetermined fixture capable of holding the fixing tape 240 and attaching the fixing tape 240 to the diaphragm 230.

[0131] Figure 10 This is a schematic diagram illustrating an example of the construction of a fixture that may be included in process S40. (Refer to...) Figure 10The clamp J1 may have a clamp structure capable of physically clamping both end portions of the fixing band 240. There are no particular limitations on the shape or method of operation of the clamp structure, as long as it can clamp both end portions of the fixing band 240 and allow the fixing band 240 to detach from the clamp structure by operation. As an example, in Figure 10 In the diagram, the clip structure is shown as a combination of a first clip portion J1a and a second clip portion J1b.

[0132] By using Figure 10 The clamp J1 shown in the diagram can clamp the two end portions of the fixing strap 240 through the first clamp portion J1a and the second clamp portion J1b ​​while simultaneously bringing the fixing strap 240 into contact or close contact with the clamp J1. For example, the inner surface of the fixing strap 240 that contacts or closely contacts the clamp J1 can be non-adhesive, while the outer surface of the fixing strap 240 can have adhesive properties due to the application of an adhesive or the like. Furthermore, by clamping the clamp J1... Figure 10 Insert the cable into the core portion of the electrode assembly 200 in the state shown. Operate the first clip portion J1a and the second clip portion J1b ​​to release the clamps on the two end portions of the fixing strap 240 and bring the outer surface of the fixing strap 240 into contact with the diaphragm 230. The outer surface of the fixing strap 240 can be attached to the diaphragm 230.

[0133] Figure 11A This is a diagram schematically illustrating another example of the construction of a fixture that may be included in process S40. Additionally, Figure 11B and Figure 11C Each is an illustrative representation of its use. Figure 11A The diagram shows the clamp holding the fixing strap in place. (Refer to...) Figures 11A to 11C The clamp J2 may have a cylindrical structure capable of attaching the fixing band 240 to its outer surface using a predetermined or desired suction force. When the cylindrical clamp J2 has multiple holes formed on its surface and an empty interior allowing air to be drawn in, thereby generating suction through the holes to attach the fixing band 240 to the outer surface of the clamp J2, there are no particular limitations on the shape of the holes or the method of operation of the clamp J2. As an example, such as... Figure 11B As shown, the suction force in clamp J2 can be generated across the entire outer peripheral surface of clamp J2, or as... Figure 11C As shown, the suction force in clamp J2 can be generated only on a portion of the outer peripheral surface of clamp J2.

[0134] By using Figure 11AThe clamp J2 shown, with its clip structure, can hold the fixing band 240 by attaching it to the entire outer peripheral surface of the clamp J2, or to a portion thereof, through suction generated via the holes. For example, the inner surface of the fixing band 240 that contacts or is in close contact with the clamp J2 can be non-adhesive, while the outer surface of the fixing band 240 can become adhesive due to the application of an adhesive or the like. Furthermore, by... Figure 11A In the state shown, the clamp J2 is inserted into the core portion of the electrode assembly 200, the suction is removed to release the fixing strap 240 from the clamp J2, and if necessary, the outer surface of the fixing strap 240 is brought into contact with the diaphragm 230 to attach the outer surface of the fixing strap 240 to the diaphragm 230.

[0135] According to an example embodiment of this disclosure, by using a fixing strap to secure the diaphragm at the core portion to the inner surface of the cylindrical electrode assembly, it is possible to substantially prevent the diaphragm from intersecting with the core portion and causing obstruction in subsequent processes. Furthermore, by using a porous fixing strap to secure the diaphragm, the reduction in the impregnation properties of the electrode assembly caused by the fixing strap can be mitigated or suppressed. Specifically, by partially attaching the end portion of the diaphragm with a porous fixing strap, the reduction in the impregnation properties of the electrode assembly can be further mitigated or suppressed.

[0136] However, those skilled in the art will understand that the effects achievable through this disclosure are not limited to those described above, and that other advantages of this disclosure will be better understood through a detailed description.

[0137] Although the above disclosure has been described with reference to exemplary embodiments shown in the accompanying drawings, it should be understood that the disclosure is not limited to the disclosed exemplary embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[0138] Therefore, the scope of this disclosure should be determined solely by the appended claims.

Claims

1. An electrode assembly having a cylindrical shape, said electrode assembly being formed by winding a stack multiple times to create a core, said stack having: A diaphragm is placed between the positive and negative electrodes. The electrode assembly includes a retaining strap configured to secure the diaphragm exposed at the core to the inner surface of the electrode assembly.

2. The electrode assembly according to claim 1, wherein, The fixing strip includes an electrically insulating film.

3. The electrode assembly according to claim 2, wherein, The electrically insulating film includes at least one of polyimide resin, polyethylene resin, and polyester resin.

4. The electrode assembly according to claim 1, wherein, The fixing band includes a porous membrane.

5. The electrode assembly according to claim 4, wherein, The porous membrane includes a substrate membrane having a plurality of pores formed therein.

6. The electrode assembly according to claim 5, wherein, The area occupied by the plurality of pores is in the range of 10% to 90% of the area of ​​the substrate film.

7. The electrode assembly according to claim 5, wherein, The plurality of pores are uniform in size and are regularly arranged on the entire surface of the substrate film.

8. The electrode assembly according to claim 5, wherein, The plurality of pores are non-uniform in size or irregularly arranged on the entire surface of the substrate film.

9. The electrode assembly according to claim 5, wherein, The planar shape of at least one of the plurality of holes is one of a circle, an ellipse, and a polygon.

10. The electrode assembly according to claim 1, wherein, The fixing strap includes an upper fixing strap and a lower fixing strap, which are attached to the upper and lower sides of the diaphragm, respectively, to cross the end portion of the diaphragm.

11. The electrode assembly of claim 10, wherein, The fixing band also includes one or more intermediate fixing bands attached to the diaphragm between the upper fixing band and the lower fixing band.

12. The electrode assembly according to claim 1, wherein, The retaining strap is attached along the end portion of the diaphragm.

13. A method for manufacturing an electrode assembly, the method comprising: Prepare a stack in which the diaphragm is placed between the positive and negative electrodes; Clamp one end portion of the diaphragm and wind the stack multiple times to form the electrode assembly having a cylindrical shape; The diaphragm exposed at the core of the electrode assembly is brought into contact with the inner surface of the electrode assembly. as well as A retaining strap is inserted into the core, and the retaining strap is used to secure the diaphragm that is in contact with the inner surface of the electrode assembly.

14. A battery, the battery comprising: Cylindrical shell; as well as The electrode assembly according to any one of claims 1 to 12.

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