Cable-type secondary battery

Abstract

Provided is a cable-type secondary battery comprising: a separator having a corrugated tube structure; a first electrode extending in the separator having the tube structure; and a second electrode extending along the first electrode while surrounding the separator having the tube structure. The cable-type secondary battery of the present invention is simple to manufacture and has excellent formability into a desired form.

Description

Cable-type secondary battery

[0001] The present invention relates to a cable-type secondary battery, and more specifically, to a cable-type secondary battery that is simple to manufacture and has excellent formability into a desired shape.

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0119497, filed September 3, 2024, the entire disclosure of which is incorporated herein by reference.

[0003] Typically, secondary batteries are mostly cylindrical, prismatic, or pouch-shaped. This is because secondary batteries are manufactured by mounting an electrode assembly, consisting of a cathode, anode, and a separator, within a cylindrical or prismatic metal can or a pouch-shaped case made of aluminum laminate sheet, and injecting an electrolyte into the electrode assembly. Therefore, a certain amount of space is essential for mounting the secondary battery, and the cylindrical, prismatic, or pouch-shaped form of the secondary battery poses a problem that limits the development of various types of portable devices. Therefore, there is a need for a novel form of secondary battery that is easily deformable.

[0004] The task to be achieved by the present invention is to provide a cable-type secondary battery that is simple to manufacture and has excellent formability in a desired shape.

[0005] In order to achieve the above technical task, the present invention provides a cable-type secondary battery including a separator having a wrinkled tube structure; a first electrode extending within the separator having the tube structure; and a second electrode extending along the first electrode while surrounding the separator having the tube structure.

[0006] In some embodiments, the separator may be adhered to the first electrode by heat shrinkage.

[0007] In some embodiments, the separator may be wrinkled in a direction perpendicular to the extension direction of the separator.

[0008] In some embodiments, the separator may include a portion in which the cross-section cut in the extension direction of the first electrode overlaps in a Z shape.

[0009] In some embodiments, the separator may be continuous in that the cross-section cut in the extension direction of the first electrode repeats a Z-shaped overlapping portion.

[0010] In some embodiments, the separator extends from one end to the other end of the cable-type secondary battery and may have a corrugated tube structure for a portion of the entire extension length.

[0011] In some embodiments, the corrugated tube structure may be a body of revolution in which one side of a cross-section cut in the extension direction of the separator is rotated about a central axis.

[0012] In some embodiments, the separator of the corrugated tube structure may not be spirally wound.

[0013] In some embodiments, the first electrode may further include a flexible support on the inside, and the first electrode may be configured to extend in a spiral manner around the flexible support.

[0014] In some embodiments, the cable-type secondary battery may further include a spirally wound packaging surrounding the outer periphery of the second electrode.

[0015] Another aspect of the present invention provides a cable-type secondary battery, comprising: a cable-type electrode assembly extending in a longitudinal direction, including a first electrode, a second electrode, and a separator provided between the first electrode and the second electrode; packaging surrounding an outer periphery of the cable-type electrode assembly; and an electrolyte provided within the packaging, wherein the separator has a tube structure that is wrinkled in a direction perpendicular to the longitudinal direction.

[0016] In some embodiments, the separator may include polypropylene, polyethylene, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalate, ethylene-butene copolymer, ethylene-hexene copolymer, or ethylene-methacrylate copolymer.

[0017] In some embodiments, the separator may include a portion having a sawtooth shape in a cross-section cut in the extension direction of the separator.

[0018] In some embodiments, the separator comprises repeating units that are repeated in the longitudinal direction, each of the repeating units comprising a first portion having a first slope with respect to the longitudinal direction; and a second portion having a second slope that is gentler than the first slope with respect to the longitudinal direction, wherein the first portion and the second portion can be connected to each other.

[0019] In some embodiments, the separator is adhered to the outside of the first electrode by thermal shrinkage, and the first portion and the second portion may have a third slope and a fourth slope, respectively, which are steeper than the first slope and the second slope before the thermal shrinkage.

[0020] The cable-type secondary battery of the present invention is simple to manufacture and has excellent formability into a desired shape.

[0021] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0022] FIG. 1 is a perspective view showing a cable-type secondary battery according to one embodiment of the present invention.

[0023] Figure 2 is a partial cross-sectional view showing a cross-section of a separator of a cable secondary battery cut along the longitudinal direction of the first electrode.

[0024] Figure 3 is a perspective view showing the above repeating unit.

[0025] Figure 4 is a cross-sectional view showing the appearance of the separator before heat shrinkage.

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the present invention may be modified in various different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. It is preferable to interpret that the embodiments of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art. Like numbers refer to like elements throughout. Furthermore, various elements and areas in the drawings are schematically drawn. Therefore, the present invention is not limited by the relative sizes or spacings depicted in the accompanying drawings.

[0027] While terms like "first" and "second" may be used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, a first component could be referred to as a "second component," and vice versa, without departing from the scope of the present invention.

[0028] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the inventive concept. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the expressions "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, operations, components, parts, or combinations thereof.

[0029] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Furthermore, it is to be understood that commonly used terms, such as those defined in dictionaries, should be interpreted to have a meaning consistent with their meaning within the relevant technical context, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0030] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0031] In the accompanying drawings, variations in the shapes depicted may be expected, for example, depending on manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention should not be construed as being limited to the specific shapes of the regions depicted herein, but should include, for example, changes in shapes resulting from the manufacturing process. All terms "and / or" used herein include each and every combination of one or more of the mentioned components. In addition, the term "substrate" used herein may mean the substrate itself, or a laminated structure including the substrate and a predetermined layer or film formed on the surface thereof. In addition, the "surface of the substrate" in this specification may mean the exposed surface of the substrate itself, or the outer surface of a predetermined layer or film formed on the substrate.

[0032]

[0033] Fig. 1 is a perspective view showing a cable-type secondary battery (100) according to one embodiment of the present invention. Fig. 2 is a partial cross-sectional view showing a cross-section of a separator (140) of a cable secondary battery (100) cut along the longitudinal direction of a first electrode (130).

[0034] Referring to FIGS. 1 and 2, the cable-type secondary battery (100) includes a separator (140) having a wrinkled tube structure, a first electrode (130) extending within the separator (140), and a second electrode (150) extending along the first electrode (130) while surrounding the separator (140). The first electrode (130), the separator (140), and the second electrode (150) can form a cable-type electrode assembly.

[0035] The first electrode (130) is either an anode or a cathode, and the second electrode (150) is the other of the anode and the cathode. Hereinafter, a case in which the first electrode (130) is an anode and the second electrode (150) is a cathode will be described. A person skilled in the art will be able to easily infer the configuration in the case in which the first electrode (130) is a cathode and the second electrode (150) is an anode from the following contents.

[0036]

[0037] First electrode (130)

[0038] The above first electrode (130) may include a positive electrode current collector (134) and a positive electrode active material layer (132) provided on its surface.

[0039] The above-described positive electrode collector (134) may include, for example, one manufactured using stainless steel, aluminum, nickel, titanium, sintered carbon or copper; stainless steel surface-treated with carbon, nickel, titanium or silver; an aluminum-cadmium alloy; a non-conductive polymer surface-treated with a conductive material; or a conductive polymer.

[0040] In order to increase the surface area of ​​the above-described positive electrode current collector (134), a plurality of recessed portions may be formed on at least one surface. At this time, the plurality of recessed portions may have a continuous pattern or an interrupted pattern. That is, the recessed portions may have a continuous pattern formed longitudinally and spaced apart from each other, or may have an interrupted pattern in which a plurality of holes are formed. The plurality of holes may be circular or polygonal.

[0041] The above-mentioned positive electrode current collector (134) serves to collect electrons generated by the electrochemical reaction of the active material or to supply electrons necessary for the electrochemical reaction. Generally, a metal such as copper or aluminum can be used. In particular, when a polymer conductor composed of a non-conductive polymer or a conductive polymer surface-treated with a conductive material is used, flexibility is relatively superior compared to when a metal such as copper or aluminum is used. In addition, a polymer current collector can be used instead of a metal current collector to achieve a lighter battery.

[0042] The conductive materials may include polyacetylene, polyaniline, polypyrrole, polythiophene, polysulfonate, ITO (Indium Tin Oxide), silver, palladium, and nickel, and the conductive polymers may include polyacetylene, polyaniline, polypyrrole, polythiophene, and polysulfonate. However, the type of non-conductive polymer used in the current collector is not particularly limited.

[0043] The positive electrode active material layer (132) is, for example, LiCoO2, LiNiO2, LiMn2O4, LiCoPO4, LiFePO4, and LiNi 1-x-y-z Co x M1 y M2 z It 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. However, the present invention is not limited thereto.

[0044]

[0045] Second electrode (150)

[0046] The second electrode (150) may include a negative electrode current collector (154) and a negative electrode active material layer (152) provided on the surface thereof.

[0047] The negative electrode current collector (154) may be made of 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; conductive polymer; paste containing powders of Ni, Al, Au, Ag, Al, Pd-Ag, Cr, Ta, Cu, Ba or ITO; or carbon paste containing carbon powder of graphite, carbon black or carbon nanotubes. At this time, the conductive material and conductive polymer may be the same as those used in the positive electrode current collector (134) described above.

[0048] The above negative active material layer (152) may include any one active material particle selected from the group consisting of natural graphite, artificial graphite, or carbon-based materials; lithium-containing titanium composite oxide (LTO); metals (M) such as Si, Sn, Li, Zn, Mg, Cd, Ce, Ni, or Fe; alloys composed of the above metals (M); oxides (MOx) of the above metals (M); and composites of the above metals (M) and carbon, or a mixture of two or more thereof.

[0049] At least one of the first electrode (130) and the second electrode (150) may further include a primer coating layer. The primer coating layer may improve adhesion between the active material layer (132, 152) and the current collector (134, 154). In some embodiments, the primer coating layer may include a conductive material and a binder.

[0050] 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.

[0051] 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 (cellulose acetate propionate), cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, styrene-butadiene rubber, acrylonitrile-styrene-butadiene copolymer, and polyimide, or a mixture of two or more thereof.

[0052]

[0053] membrane (140)

[0054] Any material used as a separator of a secondary battery may be used for the separator (140). In some embodiments, a material that can be shrunk by heat may be used for the separator (140). In some embodiments, the separator (140) may include polypropylene, polyethylene, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalate, ethylene-butene copolymer, ethylene-hexene copolymer, or ethylene-methacrylate copolymer.

[0055] The above separator (140) may have a wrinkled tube structure. As illustrated in FIG. 1, the wrinkles of the tube structure may be wrinkled in a direction substantially perpendicular to the extension direction of the separator (10).

[0056] The above-described separator (140) may have repeating units (140u) that are repeated in the longitudinal direction (L). Here, the longitudinal direction (L) does not necessarily mean a specific direction on the coordinate axis, but rather means any direction in which the separator (140) extends. If the separator (140) extends in a straight direction, the direction along the straight line may be the longitudinal direction (L), and if the separator (140) extends in a curved direction, the direction along the curve may be the longitudinal direction (L).

[0057] Figure 3 is a perspective view showing the above repeating unit (140u).

[0058] Referring to FIG. 3, the repeating unit (140u) may be a body of revolution in which one side of a cross-section cut in the extension direction of the separation membrane (140) is rotated about a central axis C. Each of the repeating units (140u) forming the separation membrane (140) may form a body of revolution as described above. The body of revolution may be continuously repeated along the extension direction (L) of the separation membrane (10).

[0059] Furthermore, the separator (140) may not be a ribbon-shaped separator wound in a spiral shape along the longitudinal direction (L).

[0060] In some embodiments, the separator (140) may have a sawtooth shape in a cross-section cut in the extension direction (L) of the separator (140). In some embodiments, the separator (140) may have a zigzag shape in a cross-section cut in the extension direction (L) of the separator (140). In some embodiments, the separator (140) may have a Z-shape in a cross-section cut in the extension direction (L) of the separator (140).

[0061] The repeating unit (140u) of the above separation membrane (140) may include a first portion (141) and a second portion (142) having different slopes with respect to the longitudinal direction (L). The first portion (141) may have a first slope θ1 with respect to the longitudinal direction (L). The second portion (142) may have a second slope θ2 with respect to the longitudinal direction (L). The first slope θ1 may be greater than the second slope θ2, and the second slope θ2 with respect to the longitudinal direction (L) may be gentler than the first slope θ1.

[0062] In FIGS. 2 and 3, the portion where the first portion (141) and the second portion (142) meet is depicted as sharp, but this is for convenience of illustration, and the present invention is not limited thereto. In some embodiments, the portion where the first portion (141) and the second portion (142) meet may include a curved surface.

[0063] In some embodiments, the separator (140) may be formed by a heat shrinkage process. Fig. 4 is a cross-sectional view showing the appearance of the separator (140) before heat shrinkage.

[0064] Referring to FIGS. 2 and 4, the first part (141) and the second part (142) of the separation membrane (140) before thermal shrinkage may have a greater slope in the longitudinal direction (L) than the first part (141) and the second part (142) after thermal shrinkage. Specifically, the first part (141) may have a third slope θ3 before thermal shrinkage, and the third slope θ3 may have a steeper slope than the first slope θ1 after thermal shrinkage. In addition, the second part (142) may have a fourth slope θ4 before thermal shrinkage, and the fourth slope θ4 may have a steeper slope than the second slope θ2 after thermal shrinkage.

[0065] The separator (140) may extend from one end to the other end of the cable-type secondary battery (100). In some embodiments, the separator (140) may have a corrugated tube structure along its entire length. Since the separator (140) has a corrugated tube structure along its entire length, sufficient flexibility can be secured against any deformation.

[0066] In some embodiments, the separator (140) may have a corrugated tube structure for a portion of its entire extended length. Because it has a corrugated tube structure for a required portion of its entire extended length, manufacturing costs are low and weight reduction is possible.

[0067] The above separator (140) can be adhered to the outside of the first electrode (130) by heat shrinkage.

[0068]

[0069] Packaging (170)

[0070] The above cable-type electrode assembly may be covered by a packaging (170) surrounding its outer periphery.

[0071] The above packaging (170) may be configured to surround the outer edge of the second electrode (150) as an insulator to protect the cable-type electrode assembly from moisture in the air and external impact. In some embodiments, a typical polymer resin such as PVC, HDPE, or epoxy resin may be used as the packaging (170).

[0072] The packaging (170) may be wound in a spiral shape to surround the outer edge of the second electrode (150). In some embodiments, the packaging (170) may be wound while in contact with the second electrode (150). In some other embodiments, the packaging (170) may be wound to surround the outer edge of the second electrode (150) while interposing another layer.

[0073]

[0074] Support (120)

[0075] In some embodiments, the cable-type secondary battery (100) may further include a support (120) on the inner side of the first electrode (120).

[0076] The support (120) may have an open structure with a space formed inside, i.e., an electrolyte diffusion channel formed on the surface facing the first electrode (130). The open structure refers to a structure that has the open structure as a boundary surface and allows free movement of substances from the inside to the outside through this boundary surface. As a result, the electrolyte may be easily introduced and discharged in both the direction from the inside of the support (120) toward the first electrode (130) and the direction from the first electrode (130) toward the inside of the support (120).

[0077] The support (120) of such an open structure may be one or more spirally wound wires, one or more spirally wound sheets, hollow fibers, or a mesh-like support. In some embodiments, the support (120) may be flexible. In some embodiments, the support (120) may have pores on its surface that allow the electrolyte to freely move to the active material of the first electrode (130) and the active material of the second electrode (150).

[0078] In some embodiments, the coiled wire-shaped support (120) may be formed into a spring-like structure made of a polymer or metal. The polymer may be formed of a material with excellent chemical resistance and non-reactive with the electrolyte. Examples thereof include the hollow fiber material described below or the polymer for the binder described above. Furthermore, the metal may be the same as the metal constituting the current collector (134, 154) described above.

[0079] In some embodiments, the hollow fiber can be obtained using a conventional hollow fiber forming method using one or more polymers selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, polyacrylonitrile, polyimide, polyethylene terephthalate, polyamide imide, polyester imide, polyether sulfone, and polysulfone.

[0080] The above open structure support (120) can maintain the linear shape of the cable-type secondary battery (100), prevent unwanted deformation of the battery structure due to external force, and secure flexibility of the cable-type secondary battery (100) by preventing collapse or deformation of the electrode structure.

[0081] In some embodiments, the support (120) may have a structure without internal voids, such as a linear wire or a twisted wire. Such linear wires or twisted wires may also be formed from the aforementioned polymer or metal. Here, the linear wire refers to a wire shape that extends linearly in the longitudinal direction, and the twisted wire refers to a wire shape in which the linear wire does not form an internal void and is twisted and twisted within itself.

[0082] In some embodiments, the support (120) may have a diameter of about 0.1 mm to about 10 mm. In some embodiments, the support (120) may have pores on its surface having an average diameter of about 100 nm to about 10 μm.

[0083] In some embodiments, the first electrode (130) may extend along the support (120). In some embodiments, the first electrode (130) may extend along the support (120) while surrounding the support (120). In some embodiments, the first electrode (130) may have a form that extends long in a ribbon shape and may extend while winding around the support (120) in a spiral shape.

[0084] In some embodiments, the second electrode (150) may extend along the separator (140). In some embodiments, the second electrode (150) may extend along the separator (140) while surrounding the separator (140). In some embodiments, the second electrode (150) may have a form that extends long in a ribbon shape and may extend while winding the separator (140) in a spiral shape.

[0085]

[0086] Lithium ion supply core (110)

[0087] In some embodiments, the lithium ion supply core portion (110) may include a gel-type polymer electrolyte and a support. In some embodiments, the lithium ion supply core portion (110) may include a liquid electrolyte and a porous carrier.

[0088] In some embodiments, the lithium ion supply core unit (110) may include an electrolyte. The electrolyte is not particularly limited in type, but may include 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-butyrolactone), sulfolane, methyl acetate (MA), or methylpropionate (MP); Gel polymer electrolytes using poly(ethylene oxide, PEO), polyvinylidene fluoride (PVdF), poly(vinylidene fluoride-co-hexafluoropropylene, PVdF-HFP), polymethylmethacrylate (PMMA), polyacrylonitrile (PAN), or polyvinyl acetate (PVAc); or solid electrolytes using PEO, polypropylene oxide (PPO), polyethylene imine (PEI), polyethylene sulfide (PES), or PVAc; etc. In addition, these electrolytes may further include lithium salts, and these lithium salts include 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 are preferably used.

[0089] In some embodiments, the lithium ion supply core (110) may be composed solely of an electrolyte. In some embodiments, when the electrolyte is in a liquid state, the electrolyte may be used by wetting a porous carrier.

[0090]

[0091] Manufacturing method

[0092] A lithium ion supply core (110) is prepared by forming a polymer electrolyte into a wire shape using an extruder or the like. Alternatively, after preparing a support (120) with a hollow center, a non-aqueous electrolyte may be injected into the center of the support (120) to form a lithium ion supply core (110).

[0093] Optionally, a lithium ion supply core (110) may be prepared by preparing a wire-shaped carrier made of a porous material and then injecting a non-aqueous electrolyte into it.

[0094] Afterwards, a wire-shaped support (120) can be wound around the lithium ion supply core portion (110).

[0095] A positive electrode active material layer (132) is formed on a positive electrode current collector (134), and a negative electrode active material layer (152) is formed on a negative electrode current collector (154). A general coating method can be applied to form each active material layer (132, 152) on each current collector (134, 154). For example, an electrode slurry containing an active material can be coated using a comma coater or a slot die coater.

[0096] A first electrode (130), which is an anode, is wound on the support (120) to form a cable, and this is inserted into a separator (140) as illustrated in FIG. 4. After inserting the support (120) on which the first electrode (130) is wound into the separator (140), the separator (140) is heated to cause thermal shrinkage. When the separator (140) is thermally shrunk, it can have a cross-section as illustrated in FIG. 2.

[0097] The separator (140) according to embodiments of the present invention is not wound around the first electrode (130). Instead, the wound first electrode (130) is inserted into a tube-shaped separator (140) and then heat-shrinked, making manufacturing very simple. Furthermore, since the separator (140) has a wrinkled structure, it can sufficiently exhibit the flexibility necessary to be deformed into a desired shape, resulting in excellent formability.

[0098] A second electrode (150), which is a cathode, can be wound around the separator (140), and a packaging (170) can be formed to surround the second electrode (150). In some embodiments, an aluminum pouch layer can be further formed between the packaging (170) and the second electrode (150).

[0099] Here, the case where the first electrode (130) is the anode and the second electrode (150) is the cathode has been described, but a person skilled in the art will also be able to easily infer the configuration where the first electrode (130) is the cathode and the second electrode (150) is the anode from the above.

[0100]

[0101] While the embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, modifications to future embodiments of the present invention will not depart from the scope of the invention.

[0102]

[0103] [Explanation of symbols]

[0104] 100: Cable-type secondary battery

[0105] 110: Lithium-ion supply core

[0106] 120: Support

[0107] 130: First electrode

[0108] 132, 152: Whole house

[0109] 134, 154: Active material layer

[0110] 140: Membrane

[0111] 141: Part 1

[0112] 142: Part 2

[0113] 150: Second electrode

[0114] 170: Packaging

Claims

1. Separator with a wrinkled tube structure; A first electrode extended within the separator of the above tube structure; and A second electrode extending along the first electrode while surrounding the separator of the above tube structure; A cable-type secondary battery including:

2. In paragraph 1, A cable-type secondary battery, characterized in that the separator is adhered to the first electrode by heat shrinkage.

3. In paragraph 1, A cable-type secondary battery, characterized in that the separator is wrinkled in a direction perpendicular to the extension direction of the separator.

4. In paragraph 3, A cable-type secondary battery, characterized in that the separator includes a section in which the cross-section cut in the extension direction of the first electrode overlaps in a Z shape.

5. In paragraph 4, A cable-type secondary battery characterized in that the separator is continuous in that the cross-section cut in the extension direction of the first electrode is repeated in a Z-shaped overlapping portion.

6. In paragraph 1, A cable-type secondary battery characterized in that the separator extends from one end to the other end of the cable-type secondary battery and has a wrinkled tube structure for a portion of the entire extension length.

7. In paragraph 1, A cable-type secondary battery characterized in that the above-mentioned wrinkled tube structure is a body of revolution in which one side of a cross-section cut in the extension direction of the separator is rotated about a central axis.

8. In paragraph 7, The above-mentioned wrinkled tube structure separator is characterized in that it is not spirally wound.

9. In paragraph 1, Further comprising a flexible support on the inner side of the first electrode, A cable-type secondary battery characterized in that the first electrode is configured to extend in a spiral shape while surrounding the flexible support.

10. In paragraph 1, A cable-type secondary battery further characterized by including a spirally wound packaging surrounding the outer edge of the second electrode.

11. A cable-shaped electrode assembly including a first electrode, a second electrode, and a separator provided between the first electrode and the second electrode, and extending in the longitudinal direction; Packaging surrounding the outer periphery of the above cable-type electrode assembly; and Electrolyte provided within the above packaging; Including, A cable-type secondary battery in which the separator has a tube structure that is wrinkled in a direction perpendicular to the longitudinal direction.

12. In paragraph 11, A cable-type secondary battery characterized in that the separator comprises polypropylene, polyethylene, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalate, ethylene-butene copolymer, ethylene-hexene copolymer, or ethylene-methacrylate copolymer.

13. In paragraph 11, A cable-type secondary battery, characterized in that the separator includes a portion having a sawtooth shape in a cross-section cut in the extension direction of the separator.

14. In paragraph 11, The above separator comprises repeating units that are repeated in the longitudinal direction, Each of the above repeating units: a first portion having a first inclination with respect to the longitudinal direction; and A second portion having a second slope that is gentler than the first slope in the longitudinal direction; A cable-type secondary battery, characterized in that the first part and the second part are connected adjacently.

15. In paragraph 14, The above separator is adhered to the outside of the first electrode by heat shrinkage, A cable-type secondary battery, characterized in that the first part and the second part have a third slope and a fourth slope, respectively, which are steeper than the first slope and the second slope before the heat shrinkage.

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