Cable-type cell assembly, cable-type battery module and cable-type battery pack

Abstract

Morphological flexibility and mechanical durability are required for battery packs of various electronic devices according to the development of wearable devices having a morphological or mechanical deformation function. Therefore, in conventional pouch-type batteries, pouch-type batteries are connected in series or in parallel to form a battery pack in order to match capacity and voltage according to the specifications of a device to be driven, but have problems of performance degradation with respect to flexibility and mechanical stress as the thickness and the volume of a battery assembly increase, and thus, the present invention relates to a cable-type cell assembly, a cable-type battery module and a cable-type battery pack for fundamentally solving these problems, and thus can maintain mechanical durability while responding to capacity and voltage according to the specifications of an electronic device.

Description

Cable-type cell assembly, cable-type battery module and cable-type battery pack

[0001] This application claims the benefit of priority to Korean Patent Application No. 2023-0095049, filed July 21, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a cable-type cell assembly, a cable-type battery module, and a cable-type battery pack. Specifically, with the development of wearable devices capable of morphological or mechanical deformation, the battery packs of such wearable devices are also required to have morphological flexibility and mechanical durability. Accordingly, conventional pouch-type batteries are configured by connecting pouch-type batteries in series or parallel to form a battery pack in order to match the capacity and voltage according to the specifications of the device to be driven. However, as the thickness and volume of the battery assembly increases, problems arise in which performance deteriorates due to flexibility and mechanical stress. The present invention relates to a cable-type cell assembly, a cable-type battery module, and a cable-type battery pack that fundamentally solve such problems.

[0003] As the safety of rechargeable lithium secondary batteries is rapidly improving and their capacity is increasing, the types of devices that use the lithium secondary batteries as an energy source are increasing.

[0004] For example, the lithium secondary battery is not only widely used as an energy source for small, multi-functional products such as wireless mobile devices or wearable devices worn on the body, but is also used as an energy source for electric vehicles and hybrid electric vehicles, which are presented as alternatives to existing gasoline and diesel vehicles that cause air pollution, or as a medium- to large-sized battery pack for use as an energy storage system (ESS).

[0005] The above lithium secondary batteries are classified into cylindrical and prismatic battery cells, in which the electrode assembly is built into a cylindrical or prismatic metal can, and pouch-type battery cells, in which the electrode assembly is built into a pouch-type case made of aluminum laminate sheet, depending on the shape of the battery case. Among these, pouch-type battery cells have the advantages of relatively large capacity and the ability to be structurally modified.

[0006] Various wearable computer technologies and applications utilizing these secondary batteries as a power source are being developed and announced. Furthermore, electronic devices such as cell phones and laptops are being designed with curved surfaces for ergonomics. Accordingly, the secondary batteries that power these electronic devices also need to be formed with various shapes, such as curved surfaces, to accommodate the specific configurations of the devices.

[0007] To match the capacity and voltage specifications of these devices, multiple pouch cells can be connected in parallel or in series to form packs. However, this increases the thickness and volume of the entire pouch cell, reducing its flexibility. Furthermore, mechanical deformation can directly apply mechanical stress to the battery components, potentially damaging the pouch cell and degrading its performance.

[0008] In response to this, the concept of a linear battery, which is a battery with a very large ratio of length to cross-sectional diameter, has been proposed, but no technological development has been confirmed for application to cell assemblies, battery modules, and battery packs as a cell-unit concept.

[0009] Figure 1 is a schematic diagram of a cell assembly through terminal connection of a conventional pouch-type battery cell (D).

[0010] Figure 1 is a schematic diagram of a pouch-type cell assembly configured in parallel by connecting a positive lead (A) and a negative lead (B) protruding in both directions using a terminal wire (C).

[0011] Although it is relatively easy to connect multiple battery cells by stacking pouch-type cell assemblies, in the case of the cable-type cell of the present invention, technological development is required to configure a cell assembly that reflects the shape, capacity, and voltage conditions of various electronic devices.

[0012] Korean Patent Publication No. 10-2005-99903 discloses a variable battery comprising an inner electrode, an outer electrode, and an electrolyte layer interposed between the electrodes. However, the variable battery has poor flexibility. Furthermore, since the variable battery uses a polymer electrolyte to form the electrolyte layer, the electrolyte is difficult to infiltrate into the active material of the electrode, which increases the resistance of the battery and deteriorates the capacity and cycle characteristics.

[0013] In addition, when forming a cable-type secondary battery, an uneven gap is created between the separating layer interposed between the inner and outer electrodes and the electrodes. Due to this gap, there is a problem that the electrolyte does not flow smoothly into the outer electrode active material layer, which may deteriorate battery performance.

[0014] Korean Patent Publication No. 10-2017-0093575 discloses a cable-type secondary battery and a method for manufacturing the same, which includes a cable-type electrode assembly including an inner electrode, a separation layer formed to surround the outer surface of the inner electrode and prevent short-circuiting of the electrode, and an outer electrode formed to surround the separation layer, and a sheet-shaped packaging formed by spirally winding to surround the outer surface of the cable-type electrode assembly.

[0015] However, there is a difference from the technology of forming an external member for connecting multiple cable-type cells of the present invention.

[0016] Korean Patent Publication No. 10-2016-0098095 discloses a cable-type secondary battery technology including an inner electrode support, a sheet-shaped inner electrode-separation layer-outer electrode complex formed by spirally winding on the outside of the inner electrode support, and wherein the inner electrode-separation layer-outer electrode complex is formed by compressing the inner electrode, the separation layer that prevents short-circuiting of the electrodes, and the outer electrode so as to be integrated.

[0017] However, there is a difference from the technology of forming a cable-type cell assembly using the outer member of the present invention.

[0018] Therefore, there is a need to develop cable-type cell assemblies, cable-type battery modules, and cable-type battery packs that can implement the capacity and voltage required by electronic devices by packaging multiple battery cells into a final unit using cable-type cells capable of implementing high flexibility as basic battery cell units.

[0019] The present invention is intended to solve the above problems, and provides a cable-type cell assembly, a cable-type battery module, and a cable-type battery pack, which can implement the capacity and voltage required by an electronic device by finally packaging a plurality of battery cells using a cable-type cell capable of implementing high flexibility as a basic battery cell unit.

[0020] In addition, the present invention seeks to provide a cable-type cell assembly, a cable-type battery module, and a cable-type battery pack that improve mechanical flexibility and durability not only when composed of basic cells but also when composed of battery packs as a power source for electronic devices requiring flexibility and mechanical durability.

[0021] In order to achieve this purpose, a cable-type cell assembly according to the present invention may include an inner electrode support, one or more inner electrodes sequentially spirally wound around the inner electrode support, a cable-type electrode assembly having an outer separation layer and an outer electrode structure, a laminated inner member accommodating the cable-type electrode assembly, two or more cable-type cells including electrode tabs formed on the outside of the inner member for electrical connection of the cable-type electrode assembly, and an outer member formed on the outside of the inner member for physically connecting the two or more cable-type cells.

[0022] Additionally, a plurality of the above cable-type cells may be connected to the electrode tabs in parallel and / or in series.

[0023] In addition, the above-mentioned external member can connect n (n is an integer greater than 0) of the above-mentioned cable-type cells in one row.

[0024] Additionally, the outer member can come into contact with the outer side of the inner member.

[0025] In addition, the material of the above-mentioned exterior member may be composed of one or two or more materials selected from the group consisting of polymer compounds, metals, and ceramics.

[0026] In addition, the exterior member may include one or a mixture of two or more polymer compounds selected from the group consisting of PET (polyethylene terephthalate), PVC (polyvinyl chloride), HDPE (high density polyethylene), and epoxy resin.

[0027] Additionally, the outer member may be a heat-shrinkable polymer compound.

[0028] In addition, the heat-shrinkable polymer compound may include one or two or more selected from the group consisting of polyolefin, polyester, fluororesin, and polyvinyl chloride.

[0029] Additionally, the metal may include one or more of iron, carbon, chromium, manganese, stainless steel, aluminum, nickel, titanium, sintered carbon, or copper, or an alloy of two or more thereof.

[0030] Additionally, the ceramic may include one or more of clay, kaolinite, aluminum oxide (Al2O3), silicon carbide (SiC), tungsten carbide, silicon, and carbon, or a mixed ceramic of two or more of these.

[0031] Additionally, an adhesive layer may be additionally formed on the inner surface of the outer member for adhesion to the outer surface of the inner member.

[0032] In addition, the adhesive layer may be formed of one or two or more of polypropylene, polycarbonate, polyethylene, styrene butadiene rubber, sodium carboxymethylcellulose, polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, polystyrene, polyacrylonitrile, polyimide, polyacrylic acid, sodium polyacrylate, polyvinyl alcohol, sodium alginate, polymethacrylic acid, and carboxymethyl chitosan.

[0033] Additionally, the cross-section of the cable-shaped cell may be any one of a circular, oval, triangular, rectangular, square, rectangular, polygonal, and amorphous shape.

[0034] The above cable-type cell assembly may have a cross-sectional shape of at least one of horizontal, vertical, W, S, Z, U, and O.

[0035] Additionally, the outer member may include a cell receiving portion that receives the cable-type cell and a cell connecting portion that connects adjacent cell receiving portions.

[0036] Additionally, the cell connecting portion may have a predetermined length to form a gap with the adjacent cable-type cell.

[0037] Additionally, the length of the cell connection portion may be 5% to 500% of the cross-sectional length of the cable-type cell.

[0038] In addition, the cross-sections at both ends of the cell receiving portion may be in the form of an open tube corresponding to the cross-sectional shape of the cable-type cell received, or may be in the form of an opening formed in the tube shape so that only the electrode tab protrudes to the outside.

[0039] In addition, the cell connecting portion may be in a form that connects one side of the adjacent cell receiving portion, and the thickness of the cell connecting portion may be greater than the thickness of the cell receiving portion.

[0040] Additionally, the laminated internal member can accommodate the cable-type electrode assembly in a spirally wound or bagged form.

[0041] In addition, the internal electrode may be a first internal electrode in the form of a monocell including a first internal current collector and a first internal active material layer formed on one surface of the first internal current collector.

[0042] In addition, the inner electrode may be in the form of a bicell including the first inner electrode, an inner separation layer formed spirally wound on the outside of the first inner electrode, and a second inner electrode formed spirally wound on the outside of the inner separation layer.

[0043] In addition, the second internal electrode may include a second internal current collector and a second-first internal active material layer formed on both sides of the second internal current collector, and a second-second internal active material layer.

[0044] In addition, the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be a strip structure extending in one direction formed by being spirally wound and sequentially surrounding the outer surface of the cable-type electrode assembly, or a metal wire structure spirally wound and having an active material layer coated on the outer surface.

[0045] Additionally, the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be wound in a spiral shape so as not to overlap each other.

[0046] In addition, the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be wound in a spiral manner so as not to overlap and spaced apart at intervals of less than twice the width.

[0047] Additionally, each of the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the internal member can be wound in a spiral shape while overlapping.

[0048] In addition, the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the built-in member may be wound in a spiral shape so that the width of the overlapping portion is within 0.9 times the width of each.

[0049] In addition, the present invention includes a cable-type battery module including the cable-type cell assembly, wherein the cable-type battery module may include a module case in which the cable-type cell assembly is accommodated and the interior thereof includes a thermally conductive heat dissipation member.

[0050] Additionally, at least one of the cable-type cell assemblies can be stored in a space partitioned by the heat dissipation member.

[0051] Additionally, it may include a terminal assembly for electrical connection between the cable-type cell assembly and an external terminal.

[0052] In addition, the terminal assembly may include a terminal assembly body fixedly coupled to the module case so as to be connected to the electrode tab of the cable-type cell assembly, and an input / output terminal protruding from one side of the terminal assembly body so as to be electrically connected to the cable-type cell assembly.

[0053] Additionally, the electrode tabs of the cable-type cell can be formed in one direction or two directions.

[0054] In addition, the cable-type cell assembly can provide a cable-type battery module used in one or more of a smartphone, a VR device, an AR device, a wearable device, and other small devices.

[0055] In addition, a cable-type battery pack used as a power source for a medium- to large-sized device including one or more of the above cable-type battery modules can be provided.

[0056] In addition, the medium- to large-sized device may be a power tool; an electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); an electric two-wheeled vehicle including an e-bike or an e-scooter; an electric golf cart; an electric truck; an electric commercial vehicle, or a power storage system.

[0057] The present invention can also be provided in a form in which various means for solving the above problem are combined.

[0058] As described above, the cable-type cell assembly according to the present invention can maintain mechanical durability while being configured to match the capacity and voltage according to the specifications of the electronic device.

[0059] In addition, by configuring a cable-type battery module or cable-type battery pack including the cable-type cell assembly, it can be used as a power source that can be applied to various forms such as wearable devices, while ensuring flexibility and preventing mechanical stress.

[0060] Therefore, mechanical defects that may occur when manufacturing a pouch-type battery pack can be overcome by applying a cable-type battery module or cable-type battery pack.

[0061] Figure 1 is a schematic diagram of a cell assembly through terminal connection of a conventional pouch-type battery cell.

[0062] Figure 2 is a schematic diagram of terminal connection of a cable-type cell assembly according to one embodiment of the present invention.

[0063] FIG. 3 is a cross-sectional view of a curved cell implementation of a cable-type cell assembly according to one embodiment of the present invention.

[0064] FIG. 4 is a perspective view of a curved cell implementation of a cable-type cell assembly according to one embodiment of the present invention.

[0065] FIG. 5 is a schematic diagram of a parallel connection implementation of a single-row cable-type cell assembly according to one embodiment of the present invention.

[0066] Fig. 6 is a schematic diagram of a serial connection implementation of a single-row cable-type cell assembly according to one embodiment of the present invention.

[0067] Fig. 7 is a schematic diagram of a serial and parallel connection implementation of a single-row cable-type cell assembly according to one embodiment of the present invention.

[0068] Figure 8 is a schematic diagram of a cable-type battery module equipped with a single-row cable-type cell assembly according to one embodiment of the present invention.

[0069] FIG. 9 is a stress-strain graph of a conventional multiple pouch-type cell assembly and a single-row cable-type cell assembly according to an embodiment of the present invention.

[0070] Figure 10 is a graph showing the change in resistance (R / R0) according to the number of bendings of a conventional multiple pouch-type cell assembly and a single-row cable-type cell assembly according to an embodiment of the present invention.

[0071] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail, so that those with ordinary skill in the art can easily implement the present invention. However, when describing the operating principles of preferred embodiments of the present invention in detail, if a detailed description of a related known function or configuration is judged to unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0072] Additionally, the same drawing reference numerals are used for parts with similar functions and actions throughout the drawings. Throughout the specification, when a part is said to be connected to another part, this includes not only direct connections but also indirect connections with other elements intervening. Furthermore, inclusion of a component does not exclude other components unless specifically stated otherwise, but rather implies the inclusion of additional components.

[0073] Additionally, the description that concretizes or adds components may be applied to all inventions unless there are special limitations, and is not limited to the description of a specific invention.

[0074] Additionally, throughout the description and claims of the invention herein, the singular includes the plural unless otherwise stated.

[0075] Additionally, throughout the description and claims of the present invention, the term "or" includes "and" unless otherwise stated. Therefore, "comprising A or B" means all three cases of including A, including B, or including A and B.

[0076] The present invention is described in detail with examples according to the drawings.

[0077] Figure 2 is a schematic diagram of terminal connection of a cable-type cell assembly according to one embodiment of the present invention.

[0078] Referring to FIG. 2, a cable-type cell assembly includes: an inner electrode support (100); a cable-type electrode assembly (500) having a structure of one or more inner electrodes (200), an outer separation layer (300), and an outer electrode (400) sequentially spirally wound around the inner electrode support (100); a laminate-type inner member (600) that accommodates the cable-type electrode assembly (500); two or more cable-type cells (800) including electrode tabs formed on the outside of the inner member (600) for electrical connection of the cable-type electrode assembly (500); and an outer member (700) formed on the outside of the inner member (600) for physically connecting two or more of the cable-type cells (800). The electrode tabs include inner electrode tabs (230) and outer electrode tabs (430).

[0079] The above spiral is expressed as spiral or helix in English, and is a general term for a shape that is twisted and turned within a certain range, similar to the shape of a general spring.

[0080] The inner electrode (200), the outer separation layer (300), and the outer electrode (400) may have a strip structure extending in one direction.

[0081] The above laminated internal member (600) can be a battery case of a conventional pouch-type battery cell, and can be made by cutting a laminate sheet having a multiple layered structure into a strip shape. Therefore, a separate description of the material and structure of the above laminated internal member is omitted.

[0082] The internal electrode support (100) may be an open structure with a space formed inside.

[0083] The internal electrode support (100) may be one or more spirally wound wires, one or more spirally wound sheets, a twisted wire, a linear wire, a hollow fiber, or a mesh-shaped support.

[0084] The above hollow fiber may be formed of at least one selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, polyacrylonitrile, polyimide, polyethylene terephthalate, polyamide imide, polyester imide, polyether sulfone, and polysulfone.

[0085] The internal electrode support (100) may include two or more wire-shaped internal electrode supports wound in a spiral manner so as to intersect each other.

[0086] An internal electrode current collector core part, a lithium ion supply core part including an electrolyte, or a filling core part can be formed in a space formed inside the internal electrode support (100).

[0087] The above internal electrode current collector core part can be made of carbon nanotubes, stainless steel, aluminum, nickel, titanium, sintered carbon or copper; stainless steel surface-treated with carbon, nickel, titanium or silver; aluminum-cadmium alloy; non-conductive polymer surface-treated with a conductive material; or conductive polymer.

[0088] The above lithium ion supply core part may include a gel-type polymer electrolyte and a support.

[0089] The above electrolyte may be a non-aqueous electrolyte using ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), vinylene carbonate (VC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), methyl formate (MF), gamma-butyrolactone (γ-BL), sulfolane, methyl acetate (MA), or methyl propionate (MP).

[0090] The above electrolyte may include an electrolyte selected from solid electrolytes using PEO (polyethyleneoxide), PPO (polypropylene oxide), PEI (polyethylene imine), PES (polyethylene sulphide), or PVAc (polyvinyl acetate).

[0091] The above electrolyte may further include a lithium salt.

[0092] The above lithium salts are LiCl, LiBr, LiI, LiClO4, LiBF4, LiB 10 Cl 10 , LiPF6, LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, (CF3SO2)2NLi, lithium chloroborane, lithium lower aliphatic carboxylic acid, and lithium tetraphenylborate, or a mixture of two or more thereof.

[0093] The above gel-type polymer electrolyte may use PEO (polyethyleneoxide), PVdF (polyvinylidene fluoride), PVdF-HFP (poly vinylidene fluoride-co-hexafluoropropylene), PMMA (polymethymetacrylate), PAN (polyacrylonitrile), or PVAc (polyvinyl acetate).

[0094] The first internal electrode may include a first internal current collector (210) and a first internal active material layer (220) formed on one surface of the first internal current collector (210), and the external electrode may include (400), an external current collector (410) and an external active material layer (420) formed on one surface of the external current collector (410).

[0095] A polymer film layer formed on at least one of the other surfaces of the first inner current collector (210) and the other surfaces of the outer current collector (410) may be further included. By adding the polymer film layer, the thickness of the thin first inner current collector (210) and the outer current collector (410) can be supplemented to support the active material layer. In addition, rather than increasing the thickness of the first inner current collector (210) and the outer current collector (410) themselves, since a flexible polymer film layer is added, the first inner current collector (210) and the outer current collector (410) can be easily deformed during the spiral winding process.

[0096] The above polymer film layer may include one or two or more selected from the group consisting of polyolefin, polyester, polyimide, and polyamide.

[0097] A polymer support layer (440) may be further formed on the surface of at least one of the first internal active material layer (220) and the external active material layer (420).

[0098] The polymer support layer (440) may be a porous polymer layer having a pore size of 0.01 μm to 10 μm and a porosity of 5% to 95%.

[0099] The polymer support layer (440) may include a polar linear polymer, an oxide-based linear polymer, or a mixture thereof.

[0100] FIG. 3 is a cross-sectional view of a curved cell implementation of a cable-type cell assembly according to an embodiment of the present invention, and FIG. 4 is a perspective view of a curved cell implementation of a cable-type cell assembly according to an embodiment of the present invention.

[0101] Referring to FIGS. 3 and 4, a plurality of cable-type electrode assemblies (500) can be connected in parallel and / or series through internal electrode tabs (230) and external electrode tabs (430).

[0102] A plurality of cable-type electrode assemblies (500) can be connected unidirectionally or bidirectionally in parallel and / or serially to the cable-type cell through the internal electrode tabs (230) and the external electrode tabs (430).

[0103] The outer member (700) can connect n (n is an integer greater than 0) cable-type cells (800) in one row.

[0104] The outer member (700) can connect n (n is an integer greater than 0) cable-type cells (800) in one row.

[0105] The outer member (700) can connect n (n is an integer greater than 0) cable-type cells (800) in two or more rows.

[0106] The external member (700) can connect n (n is an integer greater than 0) cable-type cells (800) in two or more rows.

[0107] The above 1st or 2nd row means a form in which the cylindrical sides of the cable-type cells are arranged in one or two rows in a horizontal direction so that they are adjacent, and the above 1st or 2nd row means a form in which the cylindrical sides of the cable-type cells are arranged in one or two rows in a vertical direction so that they are adjacent.

[0108] The above n is an integer greater than 0, specifically 10,000 or less, more specifically 1,000 or less, and even more specifically 100 or less.

[0109] The outer member (700) can come into contact with the outer side of the inner member (600).

[0110] The outer member (700) can partially contact the outer side of the inner member (600).

[0111] The material of the exterior member (700) may be composed of one or two or more materials selected from the group consisting of polymer compounds, metals, and ceramics.

[0112] The above outer member (700) may include one or two or more types selected from the group consisting of PET (polyethylene terephthalate), PVC (polyvinyl chloride), HDPE (high density polyethylene), and epoxy resin as polymer compounds.

[0113] The above outer member (700) may be a heat-shrinkable polymer compound.

[0114] The above heat-shrinkable polymer compound may include one or two or more selected from the group consisting of polyolefin, polyester, fluororesin, and polyvinyl chloride.

[0115] The metal may include one or more of iron, carbon, chromium, manganese, stainless steel, aluminum, nickel, titanium, sintered carbon or copper, or an alloy of two or more thereof.

[0116] The above ceramic may include one or more of clay, kaolinite, aluminum oxide (Al2O3), silicon carbide (SiC), tungsten carbide, silicon, and carbon, or a mixed ceramic of two or more of these.

[0117] An adhesive layer for adhesion to the outer surface of the inner member (600) may be additionally formed on the inner surface of the outer member (700).

[0118] The above adhesive layer may be formed of one or two or more of polypropylene, polycarbonate, polyethylene, styrene butadiene rubber, sodium carboxymethylcellulose, polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, polystyrene, polyacrylonitrile, polyimide, polyacrylic acid, sodium polyacrylate, polyvinyl alcohol, sodium alginate, polymethacrylic acid, and carboxymethyl chitosan.

[0119] The polymer material of the adhesive layer is not limited as long as it can combine the outer member and the inner member.

[0120] The above adhesive layer can be replaced with an adhesive.

[0121] The outer member (700) may include a cell receiving portion (710) that receives the cable-type cell and a cell connecting portion (720) that connects adjacent cell receiving portions (710).

[0122] FIG. 5 is a schematic diagram of a parallel connection implementation of a single-row cable-type cell assembly according to one embodiment of the present invention.

[0123] Referring to FIG. 5, (a) and (b) are front and perspective views, respectively, of a cable-type cell assembly having a short cell connection, and (c) and (d) are front and perspective views, respectively, of a cable-type cell assembly having a long cell connection. The cross-section of the cable-type cell (800) may be any one of a circular, oval, triangular, rectangular, square, rectangular, polygonal, and amorphous shape.

[0124] In order for the cross-section of the above cable-type cell to be configured to have an angular corner, the diameter for winding must be large.

[0125] The above cable-type cell assembly may have a cross-sectional shape of at least one of horizontal, vertical, W, S, Z, U, and O.

[0126] The above cable-type cell assembly can form a curved cell assembly.

[0127] The outer member (700) is a member for connecting cable-type cells and can accommodate the inner member (600).

[0128] The cell connection portion (720) can be configured to have a predetermined length to form a gap with an adjacent cable-type cell (800).

[0129] The length of the cell connection portion (720) may be 5% to 500% of the cross-sectional length of the cable-type cell (800).

[0130] The length of the cell connection part (720) is not limited as long as it can withstand deformation stress due to shape deformation of the cable-type cell assembly.

[0131] The thickness of the cell connection portion (720) may be 100% to 400% of the thickness of the outer member (700). The thickness of the cell connection portion (720) is not limited as long as it can withstand stress due to deformation of the cable-type cell assembly.

[0132] The cross-sections of both ends of the cell receiving portion (710) may be in the form of an open tube corresponding to the cross-sectional shape of the received cable-type cell (800), or may be in the form of an opening formed in the tube shape so that only the electrode tab protrudes to the outside.

[0133] The cell connection part (720) is formed to connect one side of an adjacent cell receiving part (710), and the thickness of the cell connection part (720) may be greater than the thickness of the cell receiving part (710).

[0134] The laminated internal member (600) can accommodate the cable-type electrode assembly in a spirally wound or bag-like shape.

[0135] The internal electrode includes a first internal current collector (210), a first internal active material layer (220) formed on at least one surface of the first internal current collector, and an internal electrode tab (230), and a second internal electrode including a second internal current collector, a second internal active material layer formed on at least one surface of the second internal current collector, and an internal electrode tab (430).

[0136] The inner electrode may be configured in a form in which an inner separation layer is spirally wound on the outside of the first inner electrode, and a second inner electrode is spirally wound on the outside of the inner separation layer.

[0137] In a case where the inner electrode includes only the first inner electrode, the outer separation layer may be spirally wound on the outside of the first inner electrode, and the outer electrode may be spirally wound on the outside of the outer separation layer. This form is called a monocell form.

[0138] In a case where the inner electrode includes a first inner electrode, an inner separation layer, and a second inner electrode, the outer separation layer may be spirally wound on the outside of the inner electrode, and the outer electrode may be spirally wound on the outside of the outer separation layer. This form is called a bi-cell form.

[0139] The first inner current collector and the second inner current collector should be isolated by the inner separation layer, and the second inner current collector and the outer current collector should be isolated by the outer separation layer. The width of the inner separation layer and the outer separation layer configured in a strip shape may be larger than the width of the first inner current collector, the second inner current collector, and the outer current collector, and the length of the inner separation layer and the outer separation layer may be formed to be longer than the length of the first inner current collector, the second inner current collector, and the outer current collector.

[0140] At least one of the first inner current collector, the second inner current collector, and the outer current collector may further include a primer coating layer composed of a conductive material and a binder.

[0141] The above-mentioned conductive material may include one selected from the group consisting of carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanotube, and graphene, or a mixture of two or more thereof.

[0142] The above binder is polyvinylidene fluoride (PVDF), polyvinylidene fluoride-co-hexafluoro propylene, polyvinylidene fluoride-co-trichloroethylene, polybutyl acrylate, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate propionate), cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, styrene-butadiene rubber, acrylonitrile-styrene-butadiene copolymer, and polyimide. It may be any one selected from the group consisting of, or two or more of these.

[0143] At least one of the first inner current collector, the second inner current collector, and the outer current collector may be manufactured from stainless steel; aluminum; nickel; titanium; sintered carbon; copper; stainless steel surface-treated with carbon, nickel, titanium, or silver; aluminum-cadmium alloy; non-conductive polymer surface-treated with a conductive material; conductive polymer; paste including powder of Ni, Al, Au, Ag, Pd-Ag, Cr, Ta, Cu, Ba, or ITO (Indium Tin Oxide); or carbon paste including carbon powder of graphite, carbon black, or carbon nanotube.

[0144] The conductive polymer may be one selected from the group consisting of polyacetylene, polyaniline, polypyrrole, polythiophene, and polysulfonitride, or a mixture of two or more thereof.

[0145] When the first inner electrode and the outer electrode are cathodes and the second inner electrode is a cathode, the first inner active material and the outer active material may each independently include any one active material particle selected from the group consisting of natural graphite, artificial graphite, or a carbonaceous material; a lithium-containing titanium composite oxide (LTO); a metal (Me) selected from Si, Sn, Li, Zn, Mg, Cd, Ce, Ni, or Fe; an alloy composed of the metal (Me); an oxide (MeOx) of the metal (Me); and a complex of the metal (Me) and carbon, or a mixture of two or more thereof. When the second inner electrode is a cathode, the same as when the first inner electrode and the outer electrode are a cathode can be applied.

[0146] When the first internal electrode and the external electrode are positive electrodes and the second internal electrode is negative electrodes, the first internal active material and the external active material are each independently LiCoO2, LiNiO2, LiMn2O4, LiCoPO4, LiFePO4, and LiNi 1-x-y-z Co x M1 y M2 zIt may include any one active material particle selected from the group consisting of O2 (M1 and M2 are independently any one selected from the group consisting of Al, Ni, Co, Fe, Mn, V, Cr, Ti, W, Ta, Mg, and Mo, and x, y, and z are independently atomic fractions of oxide composition elements, 0 ≤ x < 0.5, 0 ≤ y < 0.5, 0 ≤ z < 0.5, 0 < x+y+z ≤ 1) or a mixture of two or more thereof. When the second internal electrode is a cathode, the same can be applied as when the first internal electrode and the external electrode are cathodes.

[0147] The above inner electrode includes a first inner electrode including a first inner current collector and a first inner active material layer formed on one surface of the first inner current collector. The inner electrode may include an inner separation layer formed by spirally winding on the outside of the first inner electrode and a second inner electrode formed by spirally winding on the outside of the inner separation layer.

[0148] The above second internal electrode may include a second internal current collector and a second-first internal active material layer and a second-second internal active material layer formed on both sides of the second internal current collector, respectively.

[0149] The first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be formed as a strip structure extending in one direction by being wound in a spiral shape and sequentially surrounding the outer surface of the cable-type electrode assembly.

[0150] Alternatively, the first internal electrode, the second internal electrode, and the external electrode may be a metal wire structure having an active material layer coated on the outer surface.

[0151] The above metal wire structure is in the form of an active material layer coated on the surface of a thin wire made of a metal material, and the first inner electrode, the second inner electrode, and the outer electrode, each of which is made of a metal wire structure coated with an active material layer, can be wound in a spiral shape while being closely packed with a gap therebetween or without a gap therebetween.

[0152] The first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be wound in a spiral shape so as not to overlap each other. This also applies equally to a monocell configuration composed of an inner electrode, an outer separation layer, and an outer electrode.

[0153] The first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode may be wound in a spiral manner so as not to overlap and spaced apart at intervals of less than twice the width of each other. This also applies equally to a monocell configuration composed of an inner electrode, an outer separation layer, and an outer electrode.

[0154] The first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the built-in member may be wound in a spiral shape so as to overlap each other. This also applies equally to a monocell shape composed of an inner electrode, an outer separation layer, and an outer electrode.

[0155] The first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the built-in member may be wound in a spiral shape so that the width of the overlapping portion is within 0.9 times the width of each. This also applies equally to a monocell shape composed of an inner electrode, an outer separation layer, and an outer electrode.

[0156] The inner and outer separation layers may each be an electrolyte layer or a separator.

[0157] The above separator may include a porous polymer substrate made of a polyolefin polymer selected from the group consisting of ethylene homopolymer, propylene homopolymer, ethylene-butene copolymer, ethylene-hexene copolymer, and ethylene-methacrylate copolymer; a porous polymer substrate made of a polymer selected from the group consisting of polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, and polyethylene naphthalate; a porous substrate formed of a mixture of inorganic particles and a binder polymer; or a porous coating layer formed of a mixture of inorganic particles and a binder polymer on at least one surface of the porous polymer substrate.

[0158] The above-mentioned internal member can be formed of a polymer resin.

[0159] The polymer resin may include one or two or more selected from the group consisting of PET (polyethylene terephthalate), PVC (polyvinyl chloride), HDPE (high density polyethylene), and epoxy resin.

[0160] The above-mentioned built-in member may further include a moisture barrier layer.

[0161] The above moisture barrier layer can be formed of aluminum or a liquid crystal polymer.

[0162] FIG. 6 is a schematic diagram of a serial connection implementation of a single-row cable-type cell assembly according to an embodiment of the present invention, and FIG. 7 is a schematic diagram of a serial and parallel connection implementation of a single-row cable-type cell assembly according to an embodiment of the present invention.

[0163] Referring to FIGS. 6 and 7, the cable-type cell assembly encloses five cable-type cells accommodated in an internal member with an external member (700), and a series / parallel connection is formed through an internal electrode tab (230) and an external electrode tab (430).

[0164] However, in order to prevent separation of the cable-type cell, a fixing member may be additionally formed to physically fix both ends of the cable-type cell to both ends of the outer member (700).

[0165] Figure 8 is a schematic diagram of a cable-type battery module equipped with a single-row cable-type cell assembly according to one embodiment of the present invention.

[0166] Referring to FIG. 8, a cable-type battery module (900) includes a module case (910) having a thermally conductive heat-dissipating member (930) inside, and a cable-type cell assembly in which two or more cable-type cells are provided with an external member (700) is housed in the module case (910).

[0167] At least one of the above cable-type cell assemblies can be stored in a space partitioned by a heat dissipation member (930).

[0168] The cable-type battery module (900) may include a module cover (920) that seals the cable-type cell assembly by being combined with a module case (910).

[0169] The cable-type battery module (900) may include a terminal assembly (940) for electrical connection between the cable-type cell assembly and an external terminal.

[0170] The terminal assembly (940) may include a terminal assembly body that is fixedly connected to the module case (910) to be connected to the electrode terminal of the cable-type cell assembly, and an input / output terminal (941) that protrudes from one side of the terminal assembly body to be electrically connected to the cable-type cell assembly.

[0171] The electrode tabs of the above cable-type cell can be formed in one direction or in both directions.

[0172] The above cable-type cell assembly can be used in one or more of a smartphone, a VR device, an AR device, a wearable device, and other small devices.

[0173] It may be a cable-type battery pack characterized in that it is used as a power source for a medium- or large-sized device including one or more of the above cable-type battery modules.

[0174] The above medium- to large-sized devices may be power tools; electric vehicles including electric vehicles (EV), hybrid electric vehicles (HEV), and plug-in hybrid electric vehicles (PHEV); electric two-wheeled vehicles including e-bikes and e-scooters; electric golf carts; electric trucks; electric commercial vehicles, or power storage systems.

[0175] (Comparative Example 1)

[0176] The two ends of a pouch-type cell assembly, in which five conventional pouch-type battery cells are connected to multiple terminals, were fixed and an external force was applied to the center to measure the stress according to the change in strain.

[0177] (Example 1)

[0178] The two ends of a cable-type cell assembly in which five cable-type monocells of the present invention are connected to multiple terminals are fixed, and an external force is applied to the center to measure the stress according to the change in strain.

[0179] FIG. 9 is a stress-strain graph of a conventional multiple pouch-type cell assembly and a single-row cable-type cell assembly according to an embodiment of the present invention.

[0180] Looking at Figure 9, in the case of the pouch-type battery cell assembly of Comparative Example 1, a stress value of 10 MPa or more was measured for a low strain change of 2%.

[0181] For the cable-type cell assembly of Example 1, the stress value was measured to be 6 MPa or less for a high strain change of 6% or more.

[0182] Therefore, it can be confirmed that the cable-type cell assembly has high flexibility against high external force applied to the terminal-connected cell assembly.

[0183] (Comparative Example 2)

[0184] The resistance change (R / R0) of the assembly was measured as the number of bending times increased, in which both ends of a pouch-type cell assembly, which is composed of five conventional pouch-type battery cells connected to multiple terminals, were fixed and an external force was repeatedly applied to the center.

[0185] (Example 2)

[0186] The resistance change (R / R0) of the assembly was measured according to the increase in the number of bendings in which the two ends of a cable-type cell assembly in which five cable-type cells of the present invention are connected to multiple terminals and an external force is repeatedly applied to the center.

[0187] Figure 10 is a graph showing the change in resistance (R / R0) according to the number of bendings of a conventional multiple pouch-type cell assembly and a single-row cable-type cell assembly according to an embodiment of the present invention.

[0188] Looking at Figure 10, in the case of the pouch-type cell assembly of Comparative Example 1, it can be confirmed that the resistance change increases in a linear first-order function form as the number of bending cycles increases.

[0189] In the case of the cable-type cell assembly of Example 2, it can be confirmed that there is almost no change in resistance up to 1000 bending cycles.

[0190] Anyone with ordinary knowledge in the field to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

[0191] (Explanation of symbols)

[0192] A: Positive lead

[0193] B: Negative lead

[0194] C: Terminal wire

[0195] D: Pouch-type battery cell

[0196] 100: Internal electrode support

[0197] 200: Internal electrode

[0198] 210: First internal collector

[0199] 220: First internal activation material layer

[0200] 230: Internal electrode tab

[0201] 300: External separation layer

[0202] 400: External electrode

[0203] 410: External collector

[0204] 420: External active material layer

[0205] 430: External electrode tab

[0206] 440: Polymer support layer

[0207] 500: Cable-type electrode assembly

[0208] 600: Internal parts

[0209] 700: Exterior member

[0210] 710: Cell receiving section

[0211] 720: Cell connector

[0212] 800: Cable-type cell

[0213] 900: Cable-type battery module

[0214] 910: Module Case

[0215] 920: Module cover

[0216] 930: Heat dissipation member

[0217] 940: Terminal assembly

[0218] 941: Input / output terminal

Claims

1. A cable-type electrode assembly having an internal electrode support, one or more internal electrodes sequentially spirally wound around the internal electrode support, an external separation layer, and an external electrode structure; A laminated internal member accommodating the above cable-type electrode assembly; Two or more cable-type cells including electrode tabs formed on the outside of the built-in member for electrical connection of the cable-type electrode assembly; A cable-type cell assembly including an outer member formed on the outside of the inner member to physically connect two or more cable-type cells.

2. In paragraph 1, A cable-type cell assembly in which a plurality of said cable-type cells are connected in parallel and / or in series to said electrode tabs.

3. In paragraph 2, The above outer member is a cable-type cell assembly that connects n (n is an integer greater than 0) of the above cable-type cells in one row.

4. In paragraph 1, The above outer member is a cable-type cell assembly that comes into contact with the outer side of the above inner member.

5. In paragraph 4, A cable-type cell assembly in which the material of the above outer member is composed of one or two or more materials selected from the group consisting of polymer compounds, metals, and ceramics.

6. In paragraph 5, The above outer member is a cable-type cell assembly comprising one or more polymer compounds selected from the group consisting of PET (polyethylene terephthalate), PVC (polyvinyl chloride), HDPE (high density polyethylene) and epoxy resin, or a mixture of two or more thereof.

7. In paragraph 5, The above outer member is a cable-type cell assembly made of a heat-shrinkable polymer compound.

8. In paragraph 7, A cable-type cell assembly comprising the heat-shrinkable polymer compound selected from the group consisting of polyolefin, polyester, fluororesin and polyvinyl chloride, or two or more thereof.

9. In paragraph 5, A cable-type cell assembly comprising the metal comprising one or more of iron, carbon, chromium, manganese, stainless steel, aluminum, nickel, titanium, sintered carbon or copper, or an alloy of two or more thereof.

10. In paragraph 5, The above ceramic is a cable-type cell assembly comprising one or more of clay, kaolinite, aluminum oxide (Al2O3), silicon carbide (SiC), tungsten carbide, silicon, and carbon, or a mixed ceramic of two or more thereof.

11. In paragraph 5, A cable-type cell assembly in which an adhesive layer is additionally formed on the inner surface of the outer member for adhesion to the outer surface of the inner member.

12. In paragraph 11, A cable-type cell assembly, wherein the adhesive layer is formed of one or two or more of polypropylene, polycarbonate, polyethylene, styrene butadiene rubber, sodium carboxymethylcellulose, polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, polystyrene, polyacrylonitrile, polyimide, polyacrylic acid, sodium polyacrylate, polyvinyl alcohol, sodium alginate, polymethacrylic acid, and carboxymethyl chitosan.

13. In paragraph 1, A cable-type cell assembly wherein the cross-section of the above cable-type cell is in any one of a circular, oval, triangular, rectangular, square, rectangular, polygonal, and amorphous shape.

14. In paragraph 3, The above cable-type cell assembly is a cable-type cell assembly having a cross-sectional shape of at least one of horizontal straight line, vertical straight line, W-shape, S-shape, Z-shape, U-shape, and O-shape.

15. In paragraph 1, The above outer member is a cable-type cell assembly including a cell receiving portion that receives the cable-type cell and a cell connecting portion that connects adjacent cell receiving portions.

16. In paragraph 15, The above cell connection part is a cable-type assembly having a predetermined length to form a gap with the adjacent cable-type cell.

17. In paragraph 15, A cable-type cell assembly wherein the length of the above cell connection portion is 5% to 500% of the cross-sectional length of the cable-type cell.

18. In paragraph 15, The cross-sections of both ends of the above cell receiving portion are in the form of open tubes corresponding to the cross-sectional shape of the cable-type cell received, or A cable-type cell assembly in which an opening is formed in the tube shape so that only the electrode tab protrudes to the outside.

19. In paragraph 16, The above cell connection portion is in a form that connects one side of the adjacent cell receiving portion, A cable-type cell assembly in which the thickness of the above cell connection portion is greater than or equal to the thickness of the above cell receiving portion.

20. In paragraph 1, A cable-type cell assembly in which the above laminated internal member is spirally wound or encapsulated to accommodate the above cable-type electrode assembly.

21. In paragraph 1, The above inner electrode is a cable-type cell assembly, which is a first inner electrode in the form of a monocell including a first inner current collector and a first inner active material layer formed on one surface of the first inner current collector.

22. In paragraph 21, The above inner electrode is a cable-type cell assembly in the form of a bi-cell including an inner separation layer formed spirally wound on the outside of the first inner electrode and a second inner electrode formed spirally wound on the outside of the inner separation layer.

23. In paragraph 22, A cable-type cell assembly including the second internal electrode, the second internal current collector, the second-first internal active material layer formed on each of both sides of the second internal current collector, and the second-second internal active material layer.

24. In paragraph 23, A cable-type cell assembly in which the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode are formed by being spirally wound and sequentially surrounding the outer surface of the cable-type electrode assembly, and are formed as a strip structure extending in one direction or a metal wire structure spirally wound and having an active material layer coated on the outer surface.

25. In paragraph 22, A cable-type cell assembly in which the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode are wound in a spiral shape so as not to overlap each other.

26. In paragraph 22, A cable-type cell assembly in which the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, and the outer electrode are each spirally wound so as not to overlap and spaced apart at intervals of less than twice the width.

27. In paragraph 24, A cable-type cell assembly in which each of the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the internal member is wound in a spiral shape while overlapping.

28. In paragraph 24, A cable-type cell assembly in which the first inner electrode, the inner separation layer, the second inner electrode, the outer separation layer, the outer electrode, and the built-in member are wound in a spiral shape so that the width of the overlapping portion is within 0.9 times the width of each.

29. In a cable-type battery module including a cable-type cell assembly according to any one of claims 1 to 28, A cable-type battery module including a module case in which the above cable-type cell assembly is housed and the interior thereof includes a thermally conductive heat-dissipating member.

30. In paragraph 29, The above cable-type cell assembly is a cable-type battery module in which at least one or more cable-type cell assemblies are stored in a space partitioned by the heat-dissipating member.

31. In paragraph 29, A cable-type battery module comprising a terminal assembly for electrical connection between the cable-type cell assembly and an external terminal.

32. In paragraph 29, A cable-type battery module including a terminal assembly body fixedly connected to the module case so as to be connected to the electrode tab of the cable-type cell assembly and an input / output terminal protruding from one side of the terminal assembly body so as to be electrically connected to the cable-type cell assembly.

33. In paragraph 29, A cable-type battery module in which the electrode tabs of the cable-type cell are formed in one direction or two directions.

34. In a cable-type battery module including a cable-type cell assembly according to any one of claims 1 to 28, The above cable-type cell assembly is a cable-type battery module used in one or more of a smartphone, a VR device, an AR device, a wearable device, and other small devices.

35. In paragraph 29, A cable-type battery pack characterized in that it is used as a power source for a medium- or large-sized device including one or more of the above cable-type battery modules.

36. In paragraph 35, The above medium- to large-sized device is a cable-type battery pack characterized in that it is a power tool; an electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); an electric two-wheeled vehicle including an e-bike and an e-scooter; an electric golf cart; an electric truck; an electric commercial vehicle, or a power storage system.

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