KR101367975B1 - Electrode assembly, method of manufacturing the same, and battery having the same - Google Patents

Abstract

The present invention relates to an electrode assembly, a battery comprising the same, a manufacturing method thereof and a battery comprising the same. An electrode assembly of a battery according to an embodiment of the present invention, a flexible electrically insulating film having a first main surface and a second main surface opposite thereto, the first polarity of the first polarity laminated on the first main surface of the electrically insulating film A first electrode, laminated on the second main surface of the electrically insulating film, and electrically connected to at least one of a second electrode of a second polarity having a polarity opposite to the first electrode, the first electrode, and the second electrode; One or more conductive roll cores extending to define a winding axis, and a separator disposed between the first electrode and the second electrode while the electrically insulating film is wound along the winding axis to form an electrochemical reaction region.

Description

ELECTRODE ASSEMBLY, METHOD OF MANUFACTURING THE SAME, AND BATTERY HAVING THE SAME

The present invention relates to battery technology, and more particularly, to an electrode assembly, a method for manufacturing the same, and a battery comprising the same.

The battery industry has been actively researched in accordance with the demand for development of alternative energy due to the expansion of the industry related to the portable electronic device according to the development of semiconductor manufacturing technology and communication technology and the depletion of resources. As a typical battery, a lithium primary battery has a higher voltage and a higher energy density than a conventional aqueous battery, and thus is easy to miniaturize and reduce weight. The lithium primary battery is used for various purposes such as a main power supply or a backup power supply for a portable electronic device.

A secondary battery is a battery which can be charged and discharged using the electrode material excellent in reversibility. The secondary battery is divided into cylindrical and rectangular in appearance, and is classified into a nickel-hydrogen (Ni-MH) battery, a lithium (Li) battery, a lithium ion (Li-ion) battery, and the like according to a positive electrode and a negative electrode material. These secondary batteries are gradually expanding their applications from small batteries such as mobile phones, notebook PCs, and mobile displays to medium and large batteries used in electric vehicle batteries and hybrid vehicles. Accordingly, the battery is light in weight and high in energy density, and requires not only excellent charge / discharge rate, charge / discharge efficiency and cycle characteristics, but also high stability and economy.
Related Prior Art Literature
[Patent Document 1] Korean Patent Publication No. 10-2007-0101444
[Patent Document 2] Korean Patent Publication No. 10-2010-0093375
[Patent Document 3] Korean Patent Publication No. 10-2011-0036499
[Special Document 4] Korean Patent Publication No. 10-2011-0061315

The technical problem to be solved by the present invention is not only high energy density, but also excellent in charge and discharge efficiency, charge and discharge speed and cycle characteristics, furthermore, it is possible to obtain a battery that is easy to change shape and capacity control, It is to provide an electrode assembly that is easy to form a wiring.

In addition, another technical problem to be solved by the present invention is to provide a battery including an electrode assembly having the above-described advantages.

In addition, another technical problem to be solved by the present invention is to provide a method of manufacturing an electrode assembly having the above-described advantages.

The electrode assembly of the battery according to an embodiment of the present invention for achieving the technical problem, the first electrode of the first polarity laminated on the first main surface of the electrically insulating film, the second of the electrically insulating film At least one conductive roll laminated on the main surface and extending to define a winding axis in electrical connection with at least one of a second electrode of a second polarity having a polarity opposite to the first electrode, the first electrode, and the second electrode; The core may include a separator disposed between the first electrode and the second electrode while the electrically insulating film is wound along the winding shaft to form an electrochemical reaction region.

The electrode assembly may have a roll structure in which the first electrode and the second electrode are wound to face each other with the separator interposed therebetween.

The separator may be disposed on an electrode having a polarity opposite to an electrode electrically connected to the conductive roll core among the first electrode and the second electrode.

In some embodiments, the electrically insulating film may include a leakage preventing structure formed on an edge of at least one of the first main surface and the second main surface.

The leakage preventing structure may be formed at an edge of the electrically insulating film, and the leakage preventing structure may include a partition structure, a trench structure, or a combination thereof.

The height of the barrier rib structure may be equal to or greater than the thickness of each of the first electrode and the second electrode, and the depth of the trench structure may be equal to or greater than the thickness of each of the first electrode and the second electrode. Accordingly, the pressure between the wound layers generated during the winding process of the electrode assembly may prevent or reduce leakage of the electrically active material layers of the first and second electrodes out of the wound electrode assembly.

The electrically insulating film may include a natural or synthetic flexible resinous material having flexibility. The flexible resin material is a cellulose resin, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene resin, polypropylene resin, polyvinyl chloride resin, polycarbonate (PC), polyether sulfone (PES), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyimide, tri-acetyl cellulose, polyvinyl alcohol , Ethylene-vinyl alcohol copolymer (Ethylene-Vinylalcohol copolymer), and polyamide (polyamide) resin may be any one or a combination thereof.

In some embodiments, the thickness of the electrically insulating film may be between 1 μm and 100 μm, such that the electrically insulating film may have a strength suitable for processing into a roll structure while supporting the first and second electrodes. have.

At least one of the first electrode and the second electrode may include a current collector layer and an electrical active material layer sequentially stacked on the electrically insulating film.

The thickness of the current collector layer may be 0.01 μm to 20 μm, and the thickness may be obtained by thinning the current collector layer as compared with the related art. The current collector layer may include a metal or a conductive resin composition.

The conductive roll core may include copper, nickel, chromium, aluminum, copper, titanium, stainless steel, gold, tantalum, niobium, hafnium, zirconium, vanadium, indium, cobalt, tungsten, tin, beryllium, molybdenum or alloys thereof. Can be.

In some embodiments, the cross section of the conductive roll core may have a circle, ellipse, or polygonal shape. At least one of both ends of the conductive roll core may extend to be exposed outside the edge of at least one side of the electrically insulating film.

The separator may include a microporous membrane, a woven fabric, a nonwoven fabric, an intrinsic solid polymer electrolyte membrane, a gel solid polymer electrolyte membrane, a microporous membrane coated with an inorganic ceramic powder, or a combination thereof, and the separator has a thickness of 1 μm. To 100 μm.

In some embodiments, the length of the separator may be greater than the length of the electrically insulating film, and the separator may extend to enclose the outer shell of the roll structure, thereby allowing the first and second to be separated by the separator. Short circuits between the electrodes can be prevented.

The battery including the electrode assembly according to an embodiment of the present invention for achieving the above-described other technical problem may include at least one or more electrode assembly.

The battery includes a plurality of electrode assemblies, and the separator provided between the plurality of electrode assemblies may extend from the separator of the roll structure. The battery may be for a primary battery or a secondary battery.

Method for manufacturing an electrode assembly according to an embodiment of the present invention for achieving the above another technical problem is as follows. A flexible electrically insulating film having a first main surface and a second main surface opposite thereto; A first electrode laminated on the first main surface of the electrically insulating film; A second electrode laminated on the second main surface of the electrically insulating film and having a polarity opposite to that of the first electrode; And at least one conductive roll core electrically connected to the current collecting region of at least one of the first electrode and the second electrode and extending to define a winding axis, wherein the electrode assembly is formed of the electrically insulating film. The separator is stacked on one of the first electrode and the second electrode, and the winding shaft is formed such that the first electrode and the second electrode face each other with the separator interposed therebetween to form an electrochemical reaction region. Accordingly, the electrode assembly may be wound.

At least one of the first electrode and the second electrode may include a current collector layer and an electrical active material layer sequentially stacked on the electrically insulating film, and the current collector layer may be a vapor deposition method, an electroless plating method, or a combination thereof. It can be formed by.

According to an embodiment of the present invention, since the electrode assembly is provided as a unitary structure including electrodes of different polarities on the first main surface and the second main surface of the electrically insulating film, the first electrode and the second electrode are the same. It is possible to form an electrochemical reaction region by simply winding the membrane to face each other with the separator interposed therebetween, and the conductive roll core functions as a winding shaft of the electrode assembly and is electrically connected to the external electrode or the external electrode of the battery through wiring. Since it can function as a lead, an electrode assembly can be provided that is easy to wind up and to form a wiring.

In addition, according to the embodiment of the present invention, since a thin but flexible electrically insulating film can be a support, unlike the metal, the volume of the entire electrode assembly by thinning the metal current collector layer is reduced workability with increasing thickness Can be reduced, and as a result, the energy density of the cell can be improved. In addition, since the conductive roll core functions as a winding shaft, workability can be improved by the conductive roll core when forming an electrode assembly having a roll structure.

In addition, by forming a plurality of lead tabs on at least one of the first and second electrodes implemented in a roll form, the internal resistance of the battery may be reduced by shortening the moving distance of the electrons, and thus the charge and discharge rate of the battery. And efficiency and cycle characteristics can be improved.

In addition, according to some embodiments of the present invention, the structure of the electrode assembly is simplified, a thin and flexible electrically insulating film may be a support to thin the metal current collecting layer, and to help the winding of the conductive roll core, A method of manufacturing an electrode assembly that facilitates a winding process for packaging, an easy shape and capacity adjustment, and a conductive roll core can function as an external electrode or a lead electrically connected to an external electrode through wiring. This may be provided.

1A is a cross-sectional view illustrating an electrode assembly of a battery according to an embodiment of the invention.
FIG. 1B is a plan view illustrating an electrically insulating film wound by a conductive roll core in the electrode assembly shown in FIG. 1A.
2A through 2C are cross-sectional views illustrating portions cut along II-II ′ of FIG. 1B according to other embodiments of the present invention.
3A is a cross-sectional view illustrating a roll structure in which an electrode assembly and a separator are wound according to an embodiment of the present invention.
FIG. 3B is an enlarged view of a cross section taken along II-II ′ shown in FIG. 3A.
4A to 4C are cross-sectional views illustrating a cross section of the electrode assembly shown in FIG. 1A according to embodiments of the present invention.
5 is an exploded perspective view of a battery including the electrode assembly shown in FIG. 1A.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, It is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more faithful and complete, and will fully convey the scope of the invention to those skilled in the art.

In the following drawings, thickness and size of each layer are exaggerated for convenience and clarity of description, and the same reference numerals denote the same elements in the drawings. As used herein, the term "and / or" includes any and all combinations of any of the listed items.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" include singular forms unless the context clearly dictates otherwise. Also, " comprise "and / or" comprising "when used herein should be interpreted as specifying the presence of stated shapes, numbers, steps, operations, elements, elements, and / And does not preclude the presence or addition of one or more other features, integers, operations, elements, elements, and / or groups.

Although the terms first, second, etc. are used herein to describe various elements, components, regions, layers and / or portions, these members, components, regions, layers and / It is obvious that no. These terms are only used to distinguish one member, component, region, layer or section from another region, layer or section. Thus, a first member, component, region, layer or section described below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

In addition, the term 'separation membrane' as used herein includes a separator generally used in a liquid electrolyte battery using a liquid electrolyte having a small affinity with the separator. Further, as used herein, a 'membrane' is a concept including an intrinsic solid polymer electrolyte and / or a gel solid polymer electrolyte in which the electrolyte is strongly bound to the separator and the electrolyte and the separator are recognized as the same. Thus, the separator should have its meaning defined as defined herein.

1A is a cross-sectional view illustrating an electrode assembly 400 of a battery according to an embodiment of the invention, and FIG. 1B is an electrically insulating film wound by a conductive roll core 300 in the electrode assembly 400 shown in FIG. 1A. It is a top view which shows 100.

Referring to FIGS. 1A and 1B, an electrode assembly 400 constituting a battery may include an electrically insulating film 100 having a first main surface 100a and a second main surface 100b and an electrically insulating film 100. The first electrode 110 stacked on the first main surface 100a, the second electrode 120 stacked on the second main surface 100b and having a polarity opposite to that of the first electrode 110, and the first electrode 110. It may include a conductive roll core 300 that is electrically connected to).

As shown in FIG. 1A, the separator 200 may be disposed on the second electrode 120 opposite to the first electrode 110 on which the conductive roll core 300 is disposed. However, this is exemplary, and in another embodiment, the separator 200 may be disposed on the first electrode 110, and the conductive roll core 300 may be disposed on the second electrode 120. .

In some embodiments, the electrically insulating film 100 prevents leakage of the electrical active material in the first and second electrodes 110, 120 on at least one of the first main surface 100a and the second main surface 100b. The leakage preventing structure 101 may be included. The leakage preventing structure 101 may be formed on an edge of at least one of the first main surface 110a and the second main surface 110b of the electrically insulating film 200. The leakage preventing structure according to various embodiments may be implemented by a barrier rib structure, a trench structure, or a combination of these structures. The leakage preventing structure 101 will be described later with reference to FIGS. 2A to 2C.

The electrically insulating film 100 may comprise a flexible material having sufficient mechanical strength while being suitable for processing into a roll structure. The flexible material may include a natural or synthetic flexible resin material. For example, the flexible resin material may be a cellulose resin, a polyester resin such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), a polyethylene resin, a polypropylene resin, or a polyvinyl chloride. Resin, polycarbonate (PC), polyether sulfone (PES), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyimide, tri-acetyl cellulose, polyvinyl alcohol (polyvinyl alchol), ethylene-vinyl alcohol copolymer (ethylene-vinyl alchhol copolymer), and polyamide (polyamide) resin may be any one or a combination thereof, the polyamide resin is nylon 6 (nylon6), Nylon 66 (nylon66), nylon4 (bylon4) and nylon 6-11 (nylon6-11). However, these materials are exemplary only, and the present invention is not limited thereto, and other suitable natural or synthetic flexible resin-based materials may be used.

Meanwhile, the thickness of the electrically insulating film 100 may be determined such that the electrically insulating film 100 supports the first electrode 110 and the second electrode 120 and has a strength suitable for processing into a roll structure. For example, the thickness of the electrically insulating film 100 may be in the range of 1 μm to 100 μm, preferably 1 μm to 10 μm, in which case the electrically insulating film 100 is 100 μm or less thin. Since it can provide excellent mechanical strength and workability while having a thickness, it can contribute to reducing the overall thickness of the electrode assembly 400. The advantages and features of this electrically insulating film will become more apparent from the following disclosure.

One of the first electrode 110 and the second electrode 120 disposed on the electrically insulating film 100 may be an anode and the other may be a cathode. At least one of the first electrode 110 and the second electrode 120 may include a current collector layer and an electrical active material layer sequentially stacked on the electrically insulating film 100. In the embodiment illustrated in FIG. 1, the first electrode 110 may include a first current collecting layer 111 and a first electrical active material layer 112, and the second electrode 120 may include a second current collection. The front layer 121 and the second electrical active material layer 122 may be included.

The positive electrode current collector layer may include a metal-based material such as stainless steel, titanium, aluminum, or an alloy of any one of these, and preferably aluminum or an alloy thereof. As the current collector layer for the negative electrode, a metal-based material such as copper, stainless steel, nickel, or an alloy of any one thereof may be used, and preferably, copper or an alloy of copper.

The first and second current collector layers 111 and 121 may be formed of a material other than the metal-based material described above. For example, the first and second current collector layers 111 and 121 may be formed of a conductive resin composition. The conductive resin composition may be a composite material including a resin forming a matrix and conductive fine particles such as metal fine particles or carbon fine particles dispersed in the matrix. Alternatively, the conductive resin composition may be another known resin material capable of electron conduction.

Since the electrically insulating film 100 can support the first and second current collector layers 111 and 121 and provide mechanical strength for forming a roll structure, the first and second current collector layers 111, 121 can be thinned. The thickness of each of the thinned first and second current collector layers 111 and 121 may be, for example, in a range of 0.01 μm to 20 μm, preferably 0.01 μm to 10 μm.

The first and second current collector layers 111 and 121 including the aforementioned metal-based material may be formed using a pulsed laser deposition (PLD), RF sputtering, or RF magnetron, in which a thin conductive layer may be formed. It may be formed using vapor deposition such as sputtering, DC sputtering, DC magnetron sputtering, Metal Organic Chemical Vapor Deposition (MOCVD) and Molecular Beam Epitaxy (MBE), or a combination thereof. However, this is exemplary and the present invention is not limited thereto. For example, the first and second current collector layers 111 may also be formed by an electroless plating method in which a thin film is formed by an aqueous solution reaction between the corresponding metal ions constituting the first and second current collector layers 111 and 121 and a reducing agent. , 121) can be formed.

In another embodiment, when the first and second current collector layers 111 and 121 include the above-mentioned conductive resin composition, the solid-state conductive film in which the polymer resin and the conductive material such as metal powder and carbon fine particles are mixed may be laminated or The first and second current collector layers 111 and 121 may be formed by applying the liquid conductive composition and drying the liquid conductive composition.

As described above, each of the first and second electrodes 110 and 120 includes a current collector layer and an electrically active material layer that are sequentially stacked, but this is exemplary, and embodiments of the present invention are not limited thereto. For example, materials capable of intercalation and deintercalstion of metal ions, such as carbon and carbon nanotubes, and having excellent conductivity can simultaneously function as current collectors and electrical active material layers. When the electrode is configured using the first current collector layer 111 disposed below the first electrically active material layer 112 and the second current collector layer 112 disposed on the second electrical active material layer 122 may include the electrode. The thickness of the first and second electrodes 110 and 120 may be further reduced in the assembly 400.

After the first current collector layer 111 is formed on the first main surface 100a of the electrically insulating film 100, and the second current collector layer 121 is formed on the second main surface 100b, the first current collector layer is formed. The second electrical active material layer 122 may be formed on the first electrical active material layer 112 and the second current collecting layer 121 on the 111. Each of the first and second electrical active material layers 112 and 122 may be formed on the electrically insulating film 100 by the following materials using a paste, slurry, printing process, spray process, or dry coating method. If necessary, a drying process involving natural drying or a heating process may be further performed.

The first and second electrical active material layers 112 and 122 may include the following materials depending on whether the primary and secondary batteries are used and the polarity thereof. For example, in a primary battery, the cathode active material layer may include manganese oxide, electrolytic manganese dioxide (EMD), nickel oxide, lead oxide, lead dioxide, silver oxide, iron sulfide, or conductive polymer particles. The negative electrode active material layer may include zinc, aluminum, iron, lead or magnesium particles.

In the case of the secondary battery, the positive electrode active material layer is made of at least one metal of Ni, Co, Mn, Al, Cr, Fe, Mg, Sr, V, La, Ce, and O, F, S, P, and combinations thereof. It may include a Li compound including at least one nonmetallic element selected from the group. For example, the positive electrode active material layer [formula] Li _{a A 1 - b} having a B _b D _2, in the formula, A is Ni, Co, Mn, and is selected from the group consisting of, B is Al , Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, and combinations thereof, D is selected from the group consisting of O, F, S, P, and combinations thereof And 0.95 ≦ a ≦ 1.1, and 0 ≦ b ≦ 0.5.

The negative electrode active material layer of the secondary battery may include a carbon-based material such as low crystalline carbon or high crystalline carbon capable of inserting and detaching lithium ions. The low crystalline carbon may be soft carbon or hard carbon. The high crystalline carbon is natural graphite, Kish graphite, pyrolytic carbon, liquid phase pitch based carbon fiber, meso-carbon microbeads, liquid crystal pitch (Mesophase pitches) ), Or hot calcined carbon such as petroleum or coal tar pitch derived cokes. The negative electrode active material layer may include a binder, and the binder may be vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride, polyacrylonitrile, Polymeric materials such as polymethylmethacrylate may be used. In another embodiment, in order to provide a high capacity secondary battery, the negative electrode active material layer may include metal-based or intermetallic compounds including S, Si, or Sn.

The electrical active material described above may be particles having a size of 0.01 μm to 100 μm. Preferably, the electrical active material may have a size of 0.1 μm to 15 μm. However, this is only exemplary and can be appropriately selected depending on the required characteristics of the battery. In some embodiments, when the electrically active material is not a carbon-based material such as graphite particles, the first and second active material layers 111 and 121 may further include a conductive material. The conductive material may be added in a weight ratio of about 2 to 15% with respect to the total amount mixed with the electrically active material. The conductive material may be, for example, carbon black and ultra fine graphite particles, fine carbon such as acetylene black, nano metal particle paste, or indium tin oxide (ITO) paste.

The conductive roll core 300 electrically connected to at least one of the first and second electrodes 110 and 120 may have an extended shape to define a winding axis. In addition, the conductive roll core 300 may include a metal-based material. For example, the conductive roll core 300 may include copper, nickel, chromium, aluminum, titanium, stainless steel, gold, tantalum, niobium, hafnium, and zirconium. , Vanadium, indium, cobalt, tungsten, tin, beryllium, molybdenum or alloys thereof.

The cross section of the conductive roll core 300 may have a circle, ellipse, or polygonal shape. At least one of both ends of the conductive roll core 300 may be extended to be exposed outside the edge of at least one side of the electrically insulating film to facilitate the winding process.

The separation membrane 200 may include, for example, a microporous membrane, a woven fabric, a nonwoven fabric, an intrinsic solid polymer electrolyte membrane, a gel solid polymer electrolyte membrane, a microporous membrane coated with an inorganic ceramic powder, or a combination thereof. The intrinsic solid polymer electrolyte membrane may include a straight chain polymer material or a crosslinked polymer material. The gel polymer electrolyte membrane may be a combination of any one of a plasticizer-containing polymer, a salt-containing polymer, or a pure polymer containing a salt.

The materials listed with respect to the separator 200 described above are exemplary, and any suitable electronic insulation that is easy to change shape as the separator 200 and has excellent mechanical strength does not tear or crack even when the electrode assembly 400 is deformed. Materials may be used and may have suitable ion conductivity as the electronic insulating material. The separator 200 may be a single layer film or a multilayer film, and the multilayer film may be a laminate of the same single film or a stack of single film formed of different materials.

The thickness of the separator 200 is 10 μm to 300 μm, preferably 10 μm to 40 μm, and more preferably 10 μm to 25 μm in consideration of durability, shutdown function, and battery safety. One end portions 200a and 200b of the separator 200 may further extend out of the electrically insulating film 100 so that the length of the separator 200 is longer than the length of the electrically insulating film 100. In FIG. 1A, one end 200b of both ends 200a and 200b of the separator 200 is further extended out of the electrically insulating film 100. As such, the extra separator 200 extending further out of the electrically insulating film 100 may be formed by the first and second electrodes, which may be generated by shrinkage deformation of the electrode assembly 400, which may occur during cell chemistry. The short circuit between 110 and 120 can be prevented.

In addition, when one battery is implemented as a plurality of electrode assemblies 400 in order to increase the capacity of the cells, the extra separator 200 may be disposed between the plurality of electrode assemblies 400 to provide the plurality of electrode assemblies ( 400 may be insulated from each other.

According to the electrode assembly 400 of the above-described embodiment, the structure can be simplified since the cathode and the anode can be provided as a single structure compared to the conventional electrode assembly in which electrodes of different polarities are separated and provided as two independent structures. In the battery forming process, a conventional manufacturing process of aligning two separated electrodes may be omitted, thereby simplifying the manufacturing process.

On the other hand, in the electrode assembly according to the prior art, since each metal current collector functions as a supporting structure of the electrode, the thickness of the metal current collectors corresponding to the negative electrode and the positive electrode is usually designed to be at least 20 μm or more. Therefore, considering that the thickness of the electrically active material layers corresponding to the positive electrode and the negative electrode is generally 40 μm to 100 μm, the total thickness t1 of the conventional electrode assembly is 60 μm to 120 μm. As a result, in the electrode assembly according to the related art, the thickness ratio of the first and second current collector layers 111 and 121 to the total thickness of the electrode assembly may be 1/3 to 1/6.

However, according to the above-described embodiment of the present invention, since the electrically insulating film 100, rather than the first and second current collector layers 111 and 121, serves as a mechanical support structure, the first and second current collector layers ( 111, 121) can be reduced. As a result, the thickness of each electrically active material layer is 20 µm to 50 µm, which is about the same as that of the conventional electrode assembly, and the thickness of each of the first and second current collector layers 111 and 121 is 0.01 µm, and the insulating film 100 When the thickness of 1 μm, the total thickness of the electrode assembly 400 may be 41 μm to 101 μm. Therefore, the thickness ratio t2 / t1 of each current collector t2 to the total thickness t1 of the electrode assembly 400 may be reduced to 1/41 to 1/101. As a result, the volume of the wound electrode assembly is also reduced due to the reduced volume of the electrode assembly 400, so that the energy density can be improved at the same volume as compared to the conventional electrode assembly.

In addition, according to the embodiment of the present invention, since the thin and flexible electrically insulating film 100 may be a support of the electrode assembly 400, the first and second current collector layers 111 and 121 may be thinned. Can reduce their thickness. Therefore, in the manufacturing process of the electrode assembly, the winding process for packaging the first and second current collector layers 111 and 121 can be facilitated.

Meanwhile, the conductive roll core 300 may be electrically connected to the first electrode 110 by being contacted or bonded on the surface of the first current collecting layer 111 exposed to the outside. In an embodiment of the present invention, the conductive roll core 300 may be bonded to the first current collector layer 111 using a known connection method such as a soldering method or a eutectic reaction, but the present invention is not limited thereto. For example, in another embodiment, when the first electrode 110 is a carbon-based electrode that is electrically conductive and also serves as an electrically active material, the conductive roll core 300 is directly contacted or bonded on the first electrode 110 so that the first electrode 110 is contacted or bonded. It may be electrically connected to the electrode 110.

The conductive roll core 300 may serve as a winding shaft for manufacturing the electrode assembly 400 in a roll structure using a winding process. The winding direction of the winding process of the electrode assembly 400 may be defined as a direction perpendicular to the winding axis.

In some embodiments, either one of the ends 300a, 300b of the conductive roll core 300, for example the first end 300a, may further extend outside the edge of the electrically insulating film 100. The first end 300a may function as an external electrode of the battery or as a lead electrically connected to the external electrode of the battery through wiring.

In some embodiments, a leakage preventing structure 101 may be provided on the electrically insulating film 100 to prevent the first and second electrically active material layers 112 and 122 from leaking to the outside. For example, as shown in FIG. 1B, in the case where the electrically insulating film 100 has a rectangular shape on a plane, the leakage preventing structure 101 may include all or four edges of the electrically insulating film 100. May optionally be placed in a portion of the. For example, the leakage preventing structure 101 may be formed on the remaining three edges except for the edge of the electrically insulating film 100 on which the conductive roll core 300 of the electrically insulating film 100 is formed. 101 may optionally be formed on two edges of the electrically insulating film 100 perpendicular to the winding axis defined by the conductive roll core 300.

Since the leakage preventing structure 101 provides a trench or a partition at the edge of the electrically insulating film 100, the first and second electrical active material layers 112 are applied by the pressure applied during the winding process of the electrode assembly 400. , 122 may be prevented from leaking to the outside of the electrode assembly 400. A more detailed description of the above-described leakage preventing structure 101 will be described with reference to FIGS. 2A to 2C.

2A through 2C are cross-sectional views illustrating portions cut along the line II ′ of FIG. 1B according to other embodiments of the inventive concept.

Referring to FIG. 2A, the leakage preventing structure 101 may be implemented as a partition structure protruding from each of the first main surface 100a and the second main surface 100b corresponding to the edge of the electrically insulating film 100. The height of the leakage preventing structure 101 protruding from the electrically insulating film 100 is the thickness of the first electrically active material layer (112 in FIG. 1A) of the first electrode 110 or the second of the second electrode 120. It may be equal to or greater than the thickness of the electrically active material layer (122 in FIG. 1A).

Referring to FIG. 2B, the leakage preventing structure 102 may be implemented as a trench structure formed on the first main surface 100a and the second main surface 100b corresponding to the edge of the electrically insulating film 100. The depth of the leakage preventing structure 102 implemented as the trench structure may be the thickness of the first electrical active material layer 112 of FIG. 1A or the second electrical active material layer of the second electrode 120 (FIG. 1). May be equal to or greater than the thickness of 122).

Referring to FIG. 2C, the leakage preventing structures 101 and 102 may be implemented by combining the partition structure and the trench structure described above with reference to FIGS. 2A and 2B.

Thus, with the leak-proof structure described with reference to FIGS. 2A-2C, the first and second electrodes 110, 120 and the first and second electrodes 110, 120 may be affected by the pressure between the wound layers while the electrode assembly 400 is wound. Leakage of the second electrical active material layers 112 and 122 of FIG. 1 to the outside of the electrode assembly 400 may be effectively prevented.

3A is a cross-sectional view illustrating a wound roll structure of an electrode assembly 400 and a separator 200 according to an embodiment of the present invention, and FIG. 3B is a cross-sectional view taken along line II-II 'of FIG. 3A. It is an enlarged view.

3A and 3B, the electrode assembly 400 is wound using the conductive roll core 300 as a winding shaft to implement the roll structure 600. As a result, in the roll structure 600, it arrange | positions on the 1st electrode 110 and the 2nd main surface (100b of FIG. 1A) arrange | positioned on the 1st main surface (100a of FIG. 1A) of the electrically insulating film 100. As shown in FIG. Second electrodes 120 face each other with the separator 200 therebetween.

As shown in FIG. 3A, the direction in which the electrode assembly 400 is wound may be defined such that the separator 200 is disposed at the outermost side in the roll structure 600. However, the winding direction of the above-described electrode assembly 400 is exemplary, and the electrode assembly 400 may be wound in a direction opposite to the winding direction, and in this case, the first electrode (in the roll structure 600) 110 is disposed at the outermost side. However, in any of the above two winding directions, the separator 200 is interposed between the first electrode 110 and the second electrode 120 to sandwich the separator 200 in the roll structure 600. The first and second electrodes 110 and 120 face each other, and thus, the electrochemical reaction regions RA1 and RA2 may be formed inside the roll structure 600.

Meanwhile, the roll structure 600 may be wound to have a circular cross section, as shown in FIG. 3A, but embodiments of the present invention are not limited thereto.

In addition, according to the embodiment of the present invention, as described above, since the electrically insulating film 100 having excellent flexibility and the thinned first and second current collecting layers 111 and 121 are provided, the winding process is easy. The shape of the roll structure 600 may vary. For example, the cross section of the roll structure 600 may have an ellipse and polygonal shapes such as triangles and squares. Therefore, the shape of the roll structure 600 can be appropriately controlled to correspond to a battery having various shapes such as a circular battery and a square battery.

Meanwhile, unlike the manner in which the roll structure 600 is wound in one direction, the electrode assembly 400 may be wound in another manner to provide a roll structure having a different shape. This will be described with reference to FIGS. 4A to 4C.

4A-4C are cross-sectional views showing the cross-section of the electrode assembly 400 shown in FIG. 1A in various manners.

4A-4C, roll structures are disclosed in which the electrode assembly (400 of FIG. 1A) is wound in various ways. For example, in FIG. 4A, a first curled structure 700A in which two roll structures face each other by two conductive roll cores 300 is disclosed, and in FIG. 4B, two conductive roll cores 300 are provided. The second roll structure 700B is wound so that two roll structures are wound on each other. In FIG. 4C, the first roll structure 710 is replaced by the second roll structure using one conductive roll core 300. A dual roll structure 700C is disclosed in which 720 wraps externally. In the roll structures described above, at least one separator 200 is provided that separates electrodes of different polarities to form an electrochemical reaction region with the electrode assemblies.

According to the roll structures according to the various embodiments described above, one or two or more roll structures may be packaged to constitute one battery cell, in which case a separation membrane between adjacent roll structures This may be further provided. In some embodiments, the separator disposed between the roll structures adjacent to each other may be an extra separator that further extends one end of the separator 200, as described above with reference to FIG. 1A.

5 is an exploded perspective view of a battery 1000 including the electrode assembly 400 shown in FIG. 1A.

Referring to FIG. 5, the battery 1000 may be a general cylindrical battery, but as described above, the electrode assembly 400 may have a different packaging form such as a square battery because the electrode assembly 400 may be wound to have various shapes. have.

The conductive roll core 300 is electrically connected to the first electrode 110 of the first and second electrodes 110 and 120 of the electrode structure 400 and extends to define a winding axis. One end of the 300 may be coupled with a lead wire 301 for electrical connection with terminals external to the battery.

In addition, the plurality of lead tabs 302 are electrically connected to the second electrode 120. In this case, by arranging the lead tabs 302 to be spaced apart from each other on the second electrode 120 in the electrode assembly 400 wound in a roll shape, the movement distance of the electrons is shortened, thereby reducing the electrical resistance. Charge and discharge speed and efficiency of 1000), and the cycle characteristics can be improved.

Meanwhile, in the housing 820, a suitable aqueous electrolyte solution containing salts such as potassium hydroxide (KOH), potassium bromide (KBr), potassium chloride (KCl), zinc chloride (ZnCl ₂ ), and sulfuric acid (H ₂ SO ₄ ) is rolled. The battery 1000 may be activated by being absorbed into the structure. Although not shown, a suitable battery management system for controlling stability and / or power supply characteristics during use of the battery 1000 may additionally be combined.

The battery according to the embodiment of the present invention is applied as a small battery of a small electronic device such as a computer, a display device, a mobile phone due to improved energy density and processability, or by increasing the volume by increasing the capacity of a medium-large battery for power source or power storage of an automobile It may be applied as. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be clear to those who have knowledge.

100: electrically insulating film 111: first current collector layer
112: first electrical active material 110: first electrode
101: leak-proof structure 121: second collector layer
122: second electrical active material 120: second electrode
200: separator 300: conductive roll core
1000: battery

Claims (24)

An electrically insulating film that is a flexible support having a first main surface and a second main surface opposite thereto; A first electrode of a first polarity laminated on said first main surface of said electrically insulating film; And a second electrode laminated on the second main surface of the electrically insulating film, the second electrode having a second polarity having a polarity opposite to the first electrode. And
Is disposed between the first electrode and the second electrode while being opposed to the electrically insulating film on the single electrode structure with only one of the first electrode and the second electrode interposed therebetween and wound together with the single electrode structure. A separator forming an electrochemical reaction zone,
And the first electrode and the second electrode each include a current collector layer and an electrically active material layer laminated or directly formed on the electrically insulating film so as to be integrated with the electrically insulating film, and sequentially stacked. The method of claim 1,
The electrode assembly further comprises one or more conductive roll cores extending to define a winding axis, wherein the single electrode structure and the separator are wound along the winding axis,
The conductive roll core is electrically connected to any one of the first electrode and the second electrode. The method of claim 1,
The electrically insulating film includes an electrode assembly comprising a leakage preventing structure formed at an edge of at least one of the first main surface and the second main surface. The method of claim 3, wherein
The leakage preventing structure includes a partition structure, a trench structure, or a combination thereof. 5. The method of claim 4,
The height of the barrier rib structure is equal to or greater than the thickness of each of the first electrode and the second electrode, the depth of the trench structure is characterized in that it is equal to or greater than the thickness of each of the first electrode and the second electrode. Electrode assembly. The method of claim 1,
And said electrically insulating film comprises a natural or synthetic flexible resinous material having flexibility. The method according to claim 6,
The flexible resin material is a cellulose resin, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene resin, polypropylene resin, polyvinyl chloride resin, polycarbonate (PC), polyether sulfone (PES), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyimide, tri-acetyl cellulose, polyvinyl alcohol Electrode assembly, characterized in that any one or a combination of ethylene-vinyl alcohol copolymer (Ethylene-Vinylalcohol copolymer), and polyamide-based resin. The method of claim 1,
The thickness of the electrically insulating film is an electrode assembly, characterized in that 1 to 100 ㎛. The method of claim 1,
The thickness of the electrically insulating film is an electrode assembly, characterized in that in the range of 1 ㎛ to 10 ㎛. The method of claim 9,
The thickness of the current collector layer is an electrode assembly, characterized in that 0.01 to 10 ㎛. The method of claim 9,
The current collector layer includes a metal or a conductive resin composition,
And the metal is a thinned conductive layer coated on the electrically insulating film by vapor deposition and plating. The method of claim 1,
The electrode assembly further comprising at least one conductive roll core extending to define a winding axis, wherein the single electrode structure and the separator are wound along the winding axis. 13. The method of claim 12,
Cross section of the conductive roll core has a circle, ellipse, or polygonal shape of the electrode assembly. 13. The method of claim 12,
The conductive roll core is electrically connected to any one of the first electrode and the second electrode,
At least one of both ends of the conductive roll core extends to be exposed out of an edge of at least one side of the electrically insulating film. The method of claim 1,
The separator comprises a microporous membrane, a woven fabric, a nonwoven fabric, an intrinsic solid polymer electrolyte membrane, a gel solid polymer electrolyte membrane, or a combination thereof. The method of claim 1,
Electrode assembly, characterized in that the thickness of the separator is 1 ㎛ to 100 ㎛. The method of claim 1,
The length of the separator is greater than the length of the electrically insulating film electrode assembly. 13. The method of claim 12,
The conductive roll core is electrically connected to any one of the first electrode and the second electrode,
The conductive roll core is the electrode assembly, characterized in that for winding the electrically insulating film in one direction so that the separator is exposed to the outside. 13. The method of claim 12,
The conductive roll core is electrically connected to any one of the first electrode and the second electrode,
The electrode assembly of claim 1, wherein a plurality of lead tabs spaced apart from each other are coupled to the other one of the first and second electrodes. A battery comprising at least one of the electrode assemblies of claim 1. 21. The method of claim 20,
The battery includes a plurality of electrode assemblies, the separator extending longer than the electrically insulating film, such that an extended portion of the separator is disposed between the plurality of electrode assemblies to insulate the plurality of electrode assemblies. Battery characterized in that. An electrically insulating film that is a flexible support having a first main surface and a second main surface opposite thereto; A first electrode on the first main surface of the electrically insulating film; And a second electrode having a polarity opposite to the first electrode on the second main surface of the electrically insulating film;
Stacking a separator on the single electrode structure so as to face the electrically insulating plume with only one of the first electrode and the second electrode therebetween; And
Winding the separator together with the single electrode structure such that the first electrode and the second electrode face each other with the separator therebetween to form an electrochemical reaction region,
The first electrode and the second electrode is a manufacturing method of the electrode assembly including a current collector layer and an electrical active material layer each laminated or directly formed on the insulating film to be integrated with the electrically insulating film and sequentially stacked. 23. The method of claim 22,
The thickness of the electrically insulating film is a method of producing an electrode assembly, characterized in that in the range of 1 ㎛ to 10 ㎛. The method of claim 20 or 21,
The battery includes a plurality of roll structures each including the electrode assembly,
The plurality of roll structures may include a first curl structure facing each other, a second curl structure wound up so that the two roll structures bear each other, or one or more conductive rolls extending such that any one of the plurality of roll structures defines a winding axis. In the case of including a core, a battery having a double roll structure in which one roll structure is wrapped around the outside by using the conductive roll core in common.

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