Electrode for lithium secondary battery and lithium secondary battery containing this electrode

Abstract

An electrode for a lithium secondary battery, comprising: an electrode current collector, and an electrode mixture layer and an insulating layer on at least one surface of the electrode current collector, wherein the insulating layer contains a metal-organic framework (MOF).

Description

BACKGROUND1. REGIONThe disclosures and implementations disclosed herein relate generally to an electrode for a lithium secondary battery and a lithium secondary battery including the same.2. DESCRIPTION OF THE PRIOR ARTRecently, there has been a strong research on electric vehicles capable of replacing vehicles operated with fossil fuels such as gasoline and diesel vehicles belonging to the major causative agents of air pollution, and lithium secondary batteries having high discharge voltage and power stability are mainly used as a power source for these electric vehicles.During operation of a lithium secondary battery, safety problems may occur due to short circuits inside the secondary battery. This short-circuit phenomenon may occur by direct contact between the electrodes of the secondary battery, and when the short-circuit continues, it may cause a fire in the secondary battery.Therefore, development of technologies capable of suppressing problems such as short circuits and fires in the secondary battery is required.SUMMARYThe present disclosure may be applied to improve safety of a lithium secondary battery in some embodiments.According to another aspect of the present disclosure, an increase in the amount of gas generated in a lithium secondary battery can be suppressed.According to another aspect of the present disclosure, occurrence of a short circuit inside a lithium secondary battery can be prevented.The lithium secondary battery electrode of the present disclosure and the lithium secondary battery including the same can be applied to a wide range of environmental technology such as electric vehicles, battery charging stations, and other solar power and wind power generation facilities using batteries. Moreover, the lithium secondary battery electrode of the present disclosure and the lithium secondary battery including the same may be used in environmental-friendly electric vehicles, hybrid vehicles, etc. to prevent climate conversion by suppressing air pollution and greenhouse gas emissions.In some embodiments, an electrode for a lithium secondary battery includes an electrode current collector, an electrode mixture layer on at least one surface of the electrode current collector, and an insulating layer, the insulating layer including a metal-organic framework (MOF).In some embodiments, the metal organic framework (MOF) may include at least one metal selected from the group consisting of aluminum (Al), magnesium (Mg), copper (Cu), zirconium (Zr), cerium (Ce), yttrium (Y), scandium (Sc), molybdenum (Mo), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), cadmium (Cd), calcium (Ca), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), ruthenium (Ru), gadolinium (Gd), europium (Eu), terbium (Tb), zinc (Zn), iron (Fe), and nickel (Ni).In some embodiments, the insulating layer may further include at least one polymer material selected from the group consisting of polyimide (PI), polyetherimide (PEI), polyamideimide (PAI), polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC).In some embodiments, the weight ratio between the metal organic framework (MOF) and the polymer material included in the insulating layer may be 50:50 to 99:1.In some embodiments, the content of the polymer material included in the insulating layer may be 1 to 50 wt %.In some embodiments, the thickness of the insulating layer may be less than or equal to the thickness of the electrode mixture layer.In some embodiments, the electrode current collector may include an uncoated part on which the electrode mixture layer is not disposed on a surface.In some embodiments, the insulating layer may be disposed on the uncoated part.In some embodiments, the insulating layer may be disposed to cover a portion of the electrode mixture layer from a portion of the uncoated portion.In some embodiments, the insulating layer may include a first insulating layer on the electrode current collector and a second insulating layer on the first insulating layer.In some embodiments, the first insulating layer may include an inorganic compound and the second insulating layer may include an organometallic framework (MOF).In some embodiments, the inorganic compound may include at least one compound selected from the group consisting of Al 2 O 3, TiO 2, MgO, CuO, MnO, CoO, CrO, Cr 2 O 3, NiO, ZrO 2, CeO 2, SiO, SiO 2, GeO, GeO 2, Nb 2 O3, and B 2 O 3.In some embodiments, the thickness of the first insulating layer may be less than or equal to the thickness of the second insulating layer.In some embodiments, the thickness ratio of the first insulating layer and the second insulating layer may be from 10:90 to 50:50.In some embodiments, the thickness of the first insulating layer may be from 2 μm to 10 μm.In some embodiments, the thickness of the second insulating layer may be from 10 μm to 18 μm.A lithium secondary battery according to an embodiment includes an electrode for a lithium secondary battery according to any one of the above-described embodiments.BRIEF DESCRIPTION OF THE FIGURESCertain aspects, features, and advantages of the present disclosure will be explained in the following detailed description with reference to the accompanying drawings. FIG. 1A is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to an embodiment. FIG. 1B is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment. FIG. 2A is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment. FIG. 2B is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment. FIG. 3 is a plan view schematically showing a shape of the electrode for a lithium secondary battery of FIG. 2A in the plan view.DETAILED DESCRIPTIONFeatures of the present disclosure disclosed herein will be described by way of example with reference to the accompanying drawings.Hereinafter, the technology disclosed in this specification and the embodiments thereof will be described in detail with reference to the accompanying drawings. However, the embodiment of the technology may be modified in various other forms, and the scope thereof is not limited to the embodiments described below. Moreover, the technology disclosed in this specification can be applied not only by being limited to the configurations of the embodiments described below, but can also be configured by selectively combining all or a part of the individual embodiments, so that various modifications can be made.As described above, development of a technology for suppressing short circuit inside the lithium secondary battery is required. According to an embodiment, an insulating layer may be applied to the uncoated part of the electrode current collector where the electrode mixture layer is not disposed, thereby preventing a short circuit between the electrodes. For example, when an insulating layer is applied to the uncoated part of the cathode current collector, a short circuit can be prevented even when the uncoated part comes into contact with the anode.During the operation of the lithium secondary battery, a safety problem may occur because gas is formed inside the secondary battery. The gas generated inside the secondary battery may cause a venting phenomenon in which the battery surface is opened or burst.According to an embodiment, it is possible to suppress short circuit inside a lithium secondary battery and also to reduce the amount of generated gas. The embodiments will be described in more detail below with reference to FIGS. 1A to 3.FIG. 1A is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to an embodiment.FIG. 1B is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment.FIG. 2A is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment.FIG. 2B is a cross-sectional view schematically showing an electrode for a lithium secondary battery according to another embodiment.FIG. 3 is a schematic plan view of the electrode for a lithium secondary battery shown in FIG. 2A.Electrode for a lithium secondary batteryAccording to an embodiment, an electrode (100) for a lithium secondary battery includes an electrode current collector (10), an electrode mixture layer (20) on at least one surface of the electrode current collector, and an insulating layer (30), wherein the insulating layer (30) includes an organometallic framework (MOF).In the present specification, the metal organic framework (MOF) refers to a porous material in which a metal ion or a metal cluster is bonded to an organic ligand through a coordination bond. The metal organic framework (MOF) contained in the insulating layer ( 30) can adsorb gases such as carbon dioxide (CO 2) excellently. Therefore, when the insulating layer ( 30) contains an organometallic skeleton (MOF), the amount of gas generated inside the secondary battery can be reduced and occurrence of a battery venting phenomenon can be suppressed.In some embodiments, the metal organic framework (MOF) may include at least one metal selected from the group consisting of aluminum (Al), magnesium (Mg), copper (Cu), zirconium (Zr), cerium (Ce), yttrium (Y), scandium (Sc), molybdenum (Mo), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), cadmium (Cd), calcium (Ca), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), ruthenium (Ru), gadolinium (Gd), europium (Eu), terbium (Tb), zinc (Zn), iron (Fe), and nickel (Ni).The type of the metal organic skeleton (MOF) is not particularly limited. For example, the metal organic framework (MOF) may include at least one selected from the group consisting of MOF-808, UiO-66, UiO-66-OH, CE-UiO66(BDC), UiO66-NO 2, UiO66-NMe 2, NU-1000, PCN-777, UiO-66-NH 2, UiO-67, and UiO-68.In some embodiments, the insulating layer (30) may also include a polymeric material. The polymer material is not particularly limited as long as it has insulating properties and can prevent short circuits between the electrodes. For example, the insulating layer (30) may further include at least one polymer material selected from the group consisting of polyimide (PI), polyetherimide (PEI), polyamideimide (PAI), polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC).In some embodiments, the insulating layer ( 30) may include an organometallic framework (MOF) and polyetherimide (PEI). The polyetherimide (PEI) is a material having high strength and high rigidity, excellent wear resistance and stability at high temperatures, and flame retardancy. Therefore, when the insulating layer ( 30) contains both an organometallic skeleton (MOF) and polyetherimide (PEI), deintercalation of the electrode mixture layer ( 20) in the region near the uncoated part of the electrode can be suppressed and high-temperature performance and battery firing can be prevented.In some embodiments, the weight ratio between the metal organic framework (MOF) and the polymer material included in the insulating layer may be 50:50 to 99:1. If the content of the metal organic framework (MOF) is too high, it may be difficult to ensure insulation of the insulating layer ( 30). On the other hand, if the content of the polymer material is too high, the gas adsorption amount by the metal organic skeleton (MOF) contained in the insulating layer (30) is insufficient, making it difficult to reduce the amount of gas generated in the battery.In some embodiments, the content of the metal organic framework (MOF) contained in the insulating layer ( 30) may be 50 to 99% by weight. When the content of the metal organic framework (MOF) in the insulating layer ( 30) is less than 50% by weight, it may be difficult to improve the gas adsorption properties of the insulating layer ( 30). In addition, when the content of the polymer material contained in the insulating layer ( 30) exceeds 99% by weight, it may be difficult to ensure insulation of the insulating layer ( 30).In some embodiments, the content of the polymer material included in the insulating layer ( 30) may be 1 to 50 wt %. When the content of the polymer material contained in the insulating layer ( 30) is less than 1% by weight, it may be difficult to ensure insulation of the insulating layer ( 30). In addition, when the content of the polymer material contained in the insulating layer ( 30) exceeds 50% by weight, it may be difficult to improve the gas adsorption properties of the insulating layer ( 30) due to the low content of the metal organic framework (MOF).In some embodiments, the thickness (T Y) of the insulating layer ( 30) may be less than or equal to the thickness (T X) of the electrode mixture layer ( 20). When the thickness (T Y) of the insulating layer (30) exceeds the thickness (T X) of the electrode mixture layer (20), the thickness of the battery cell may change, resulting in a failure in the arrangement of the modules.In some embodiments, the thickness (T X) of the electrode mixture layer ( 20) and the thickness (T Y) of the insulating layer ( 30) may be uniform (see FIG. 1 ) or non-uniform (see FIG. 2 ). When the thickness (T X) of the electrode mixture layer (20) and the thickness (T Y) of the insulating layer (30) are non-uniform, the thickness (T X) of the electrode mixture layer (20) and the thickness (T Y) of the insulating layer (30) may be the thickness from the surface of the electrode current collector (10) to the surface furthest in the thickness direction of the electrode mixture layer (20) and the insulating layer (30), respectively (for example, the thickness of the thickest part of the electrode mixture layer (20) and the insulating layer (30), respectively).In some embodiments, the thickness (T Y) of the insulating layer ( 30) may be 5 μm or more. In this case, the thickness (T Y) of the insulating layer ( 30) may be less than or equal to the thickness (T X) of the electrode mixture layer ( 20).The constituent elements of the above electrode current collector (10) are not particularly limited. For example, the electrode current collector ( 10) may be a plate or foil formed of one or more of indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), and alloys thereof. The thickness of the electrode current collector (10) is not particularly limited. For example, the thickness of the electrode current collector ( 10) may be 0.1 μm to 50 μm.When the electrode ( 100) for the lithium secondary battery is an anode, the electrode current collector ( 10) may be a copper foil (Cu foil) in some embodiments. When the electrode ( 100) for the lithium secondary battery is a cathode, the electrode current collector ( 10) may be an aluminum foil (Al foil) in some embodiments.The electrode current collector (10) may include an uncoated part on which no electrode mixture layer (20) is disposed on the surface. According to an embodiment, the insulating layer ( 30) may be disposed on the uncoated part (see FIGS. 1A and 1B ). According to another embodiment, the insulating layer ( 30) may be disposed to cover a part of the electrode mixture layer ( 20) from a part of the uncoated part (see FIGS. 2A, 2B, and 3 ). In this case, the region where the insulating layer ( 30) covers a part of the electrode mixture layer in the electrode ( 100) for the lithium secondary battery may be an overlap region (A).In some embodiments, the insulating layer ( 30) may include a first insulating layer ( 31) on the electrode current collector ( 10) and a second insulating layer ( 32) on the first insulating layer (see FIGS. 1B and 2B ). The first insulating layer (31) may be an insulating layer on the side adjacent to the electrode current collector (10) in the insulating layer (30) on at least one surface of the electrode current collector (10). Moreover, the second insulating layer (32) may be disposed on the first insulating layer (31) as an insulating layer on the side spaced from the electrode current collector (10) in the insulating layer (30) on at least one surface of the electrode current collector (10).In some embodiments, the first insulating layer ( 31) may include an inorganic compound and the second insulating layer ( 32) may include a metal organic framework (MOF). In this case, the insulating layer (30) may contain an inorganic compound having excellent thermal stability and an organometallic framework (MOF) having excellent gas adsorption, so that safety may be excellent.The first insulating layer ( 31) and the second insulating layer ( 32) may each include both an organometallic framework (MOF) and an inorganic compound. In this case, the weight percent of the inorganic compound in the first insulating layer ( 31) may be equal to or greater than the weight percent of the metal organic skeleton (MOF), and the weight percent of the metal organic skeleton (MOF) in the second insulating layer ( 32) may be equal to or greater than the weight percent of the inorganic compound.The second insulating layer (32) may also include a polymeric material. The polymer material is not particularly limited as long as it has insulating properties and can prevent short circuits between the electrodes. For example, the second insulating layer ( 32) may further include at least one polymer material selected from the group consisting of polyimide (PI), polyetherimide (PEI), polyamideimide (PAI), polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC).In some embodiments, the inorganic compound may be an inorganic oxide having excellent thermal stability. For example, the inorganic compound may include at least one compound selected from the group consisting of Al 2 O 3, TiO 2, MgO, CuO, MnO, CoO, CrO, Cr 2 O 3, NiO, ZrO 2, CeO 2, SiO, SiO 2, GeO, GeO 2, Nb 2 O3, and B 2 O 3.In some embodiments, the second insulating layer ( 32) may include an organometallic framework (MOF) and a polyetherimide (PEI). A detailed description of the polyetherimide (PEI) overlaps with the above-described content and is therefore omitted.In some embodiments, the weight ratio between the metal organic framework (MOF) and the polymer material included in the second insulating layer (32) may be 50:50 to 99:1. A detailed description of the weight ratio of the metal organic skeleton (MOF) and the polymer material overlaps with the above-described content and is thus omitted.In some embodiments, the content of the metal organic framework (MOF) contained in the second insulating layer ( 32) may be 50 to 99 wt %. A detailed description of the content of the metal organic framework (MOF) overlaps with the above-described content and is therefore omitted.In some embodiments, the content of the polymer material included in the second insulating layer ( 32) may be 1 to 50 wt %. A detailed description of the content of the polymer material overlaps with the above-described content and is therefore omitted.In some embodiments, the thickness of the first insulating layer (31) may be less than or equal to the thickness of the second insulating layer (32). For example, the thickness ratio of the first insulating layer ( 31) and the second insulating layer ( 32) may be 10:90 to 50:50. In this case, the thermal stability and insulation of the insulating layer (30) including the first insulating layer (31) and the second insulating layer (32) may be excellent.In some embodiments, the thickness of the first insulating layer may be 2 μm to 10 μm, and the thickness of the second insulating layer may be 10 μm to 18 μm.The electrode mixture layer (20) may contain an electrode active material. When the lithium secondary battery electrode ( 100) is an anode, the electrode mixture layer ( 20) may be an anode mixture layer containing an anode active material. When the lithium secondary battery electrode ( 100) is a cathode, the electrode mixture layer ( 20) may be a cathode mixture layer containing a cathode active material.The above anode active material is not particularly limited. For example, the anode active material may be one or more selected from the group consisting of carbon-based materials such as crystalline carbon, amorphous carbon, carbon composites and carbon fibers, lithium metal, lithium alloys, silicon-containing materials, and tin-containing materials.The crystalline carbon may be, for example, graphite-based carbon such as natural graphite, artificial graphite, graphitized coke, mesocarbon microbeads (MCMB), mesophase pitch-based carbon fibers (MPCF), etc.The amorphous carbon may be, for example, hard coal, soft coal, coke, mesocarbon microbeads (MCMB), or mesophase pitch-based carbon fibers (MPCF).The element contained in the lithium alloy may be, for example, aluminum, zinc, bismuth, cadmium, antimony, silicon, lead, tin, gallium or indium.The silicon-containing material is not particularly limited as long as it contains silicon, and may be an active material that can be alloyed with lithium (Li). The silicon-containing material may be, for example, one or more selected from the group consisting of silicon (Si), silicon oxide (SiOx; 0<x<2), metal-doped silicon oxide (SiOx; 0<x<2), carbon-coated silicon oxide (SiOx; 0<x<2), silicon-carbon composite (Si-C), and silicon alloy.The cathode active material is not particularly limited. The cathode active material may include, for example, a lithium nickel metal oxide. The lithium nickel metal oxide may further include at least one of cobalt (Co), manganese (Mn), and aluminum (Al).In some embodiments, the cathode active material or the lithium nickel metal oxide may have a layered structure or a crystal structure represented by the following Chemical Formula 1. Li x Ni a M b O 2+z[ Chemical Formula 1]In Chemical Formula 1, 0.9≤x≤1.2, 0.6≤a≤0.99, 0.01≤b≤0.4, -0.5≤z≤0.1 may be satisfied. As described above, M may contain Co, Mn and / or Al.The chemical structure represented by Chemical Formula 1 represents a bonding relationship included in the layer or crystal structure of the cathode active material, and does not exclude other additional elements. For example, M contains Co and / or Mn, and Co and / or Mn may be provided together with Ni as the main active element of the cathode active material. Chemical Formula 1 is given to express the binding relationship of the main active element, and is understood to include the introduction and substitution of additional elements.In some embodiments, additional auxiliary elements may be included in addition to the main active element to increase the chemical stability of the cathode active material or the layer / crystal structure. The auxiliary elements may be incorporated together into the layer / crystal structure to form bonds, and in this case, they are also considered to be included in the chemical structure region represented by Chemical Formula 1.The auxiliary elements may include at least one of Na, Mg, Ca, Y, Ti, Hf, V, Nb, Ta, Cr, Mo, W, Fe, Cu, Ag, Zn, B, Al, Ga, C, Si, Sn, Sr, Ba, Ra, P, or Zr, for example. The above auxiliary element may function as an auxiliary active element that contributes to the capacity / output activity of the cathode active material such as Al together with Co or Mn, for example.The cathode active material or the lithium nickel metal oxide may have, for example, a layered structure or a crystal structure represented by the following Chemical Formula 1-1. Li x Ni a M1B 1 M2B 2 O 2+z[ Chemical Formula 1-1]In Chemical Formula 1-1, M1may contain Co, Mn and / or Al. M 2 may include the auxiliary element described above. In Chemical Formula 1-1, 0.9≤x≤1.2, 0.6≤a≤0.99, 0.01≤b1+b2≤0.4, -0.5≤z≤0.1 may be satisfied.The cathode active material may also include a coating element or a dopant element. As coating or doping elements, for example, elements can be used which are substantially identical or similar to the auxiliary elements described above. For example, the above-described elements may be used alone or in combination of two or more as coating or doping elements.The coating or doping element may be present on the surface of the lithium nickel metal oxide particle or permeate through the surface of the lithium nickel metal composite oxide particle and be contained in the bonding structure represented by Chemical Formula 1 or Chemical Formula 1-1.The cathode active material may include a nickel cobalt manganese (NCM) lithium oxide. In this case, an NCM-based lithium oxide having an increased nickel content may be used.The Ni content in the NCM-based lithium oxide (e.g., the molar proportion of nickel to the total moles of nickel, cobalt, and manganese) may be 0.6 or more, 0.7 or more, or 0.8 or more. In some embodiments, the Ni content may be from 0.8 to 0.95, from 0.82 to 0.95, from 0.83 to 0.95, from 0.84 to 0.95, from 0.85 to 0.95, or from 0.88 to 0.95.In some embodiments, the cathode active material may include a lithium cobalt oxide-based active material, a lithium manganese oxide-based active material, a lithium nickel oxide-based active material, or a lithium iron phosphate-based active material (LFP) (e.g., LiFePO 4).In some embodiments, the cathode active material may include a Mn-rich active material, a Li rich layered oxide (LLO) / over lithiated oxide (OLO) active material, or a Co-free active material having a chemical structure or crystal structure of Chemical Formula 2. p [Li 2 MnO 3] · (1-p) [Li q JO 2] [ Chemical Formula 2]In Chemical Formula 2, 0<p<1, 0.9≤q≤1.2, and J may contain at least one element selected from Mn, Ni, Co, Fe, Cr, V, Cu, Zn, Ti, Al, Mg, and B.The electrode mixture layer (20) may further contain a binder. The binder is not particularly limited. The cathode mixture layer may include, for example, one or more of polyvinylidene fluoride, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate.In addition, the anode mixture layer may include a binder selected from a rubber-based binder such as styrene-butadiene rubber (SBR), fluorine-based rubber, ethylene-propylene rubber, butadiene rubber, isoprene rubber, and silane-based rubber, a cellulose-based binder such as carboxymethyl cellulose (CMC), hydroxypropylmethyl cellulose, methyl cellulose, or an alkali metal salt thereof, and a combination thereof.The above electrode mixture layer (20) may further contain a conductive material. The conductive material is not particularly limited. For example, the conductive material described above may include one or two or more of graphite such as natural graphite or artificial graphite; carbon-based materials such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, summer black, carbon fibers, carbon nanotubes (CNTs); metal powders or metal fibers such as copper, nickel, aluminum, silver; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; or conductive polymers such as polyphenylene derivatives and the like.The lithium secondary battery electrode ( 100) according to the above-described embodiments can be manufactured by the manufacturing method described below.Method for Manufacturing an Electrode for a Lithium Secondary BatteryA method for manufacturing an electrode ( 100) for a lithium secondary battery includes a process of forming an electrode mixture layer ( 20) and an insulating layer ( 30) on at least one surface of an electrode current collector ( 10), and the insulating layer ( 30) includes an organometallic skeleton (MOF). Detailed descriptions of the electrode current collector ( 10), the electrode mixture layer ( 20), the insulating layer ( 30), etc. are redundant to the above-described contents and are therefore omitted.The step of forming the electrode mixture layer (20) and the insulating layer (30) on at least one surface of the electrode current collector (10) may be performed as a process of forming an electrode mixture layer (20) on at least one surface of the electrode current collector (10) and then forming an insulating layer (30).The electrode mixture layer (20) may be formed on at least one surface of the electrode current collector (10) by applying a slurry containing an electrode active material to at least one surface of the electrode current collector (10) and drying the electrode slurry at 80 to 120° C. The method for applying the electrode slurry is not particularly limited. For example, the electrode slurry may be applied to the surface of the electrode current collector (10) by a method such as bar coating, casting or spraying.The electrode slurry may also contain a solvent. The solvent is not particularly limited. For example, dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methyl-2-pyrrolidone (NMP), acetone, water, etc. can be used as the solvent. The amount of the solvent used is not particularly limited as long as it is sufficient to dissolve or disperse the components and to attain a viscosity which ensures excellent uniformity of the layer thickness when applied to a current collector, taking into account the layer thickness of the slurry, the production yield, etc.The insulating layer (30) may be formed on at least one surface of the electrode current collector (10) by applying an insulating coating composition to at least one surface of the electrode current collector (10) and drying the composition at 80 to 120° C. The method for applying the insulating coating composition is not particularly limited. For example, the insulating coating composition may be applied to the surface of the electrode current collector (10) by a method such as bar coating, casting, or spraying.The insulating coating composition may contain an organometallic framework (MOF). The insulating coating composition may also include a polymeric material. Detailed descriptions of the metal organic framework (MOF), the polymer material, etc. overlap with the above-described contents and are therefore omitted.The insulating coating composition may further contain a solvent. The kind of the solvent is not particularly limited. The solvent may be, for example, N-methyl-2-pyrrolidone (NMP).The insulating layer ( 30) may be formed in a structure disposed on the uncoated part of the electrode current collector ( 10) (see FIG. 1 ), or may be formed in a structure disposed to cover a part of the electrode mixture layer from a part of the uncoated part (see FIGS. 2 and 3 ).Lithium secondary batteryA lithium secondary battery according to an embodiment includes an electrode ( 100) for a lithium secondary battery according to any one of the above-described embodiments. Specifically, the lithium secondary battery may include a unit cell including an electrode ( 100) for a lithium secondary battery according to any one of the above-described embodiments as an anode or a cathode.In some embodiments, the unit cell may further include a separator between the cathode and the anode. The separator is not particularly limited. For example, the separator may include a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc. In addition, the separator may include a non-woven fabric of high melting glass fibers, polyethylene terephthalate fibers, etc.In some embodiments, the lithium secondary battery may be manufactured by housing the above-described unit cell in a pouch, i.e., a battery case, and then injecting an electrolyte.The electrolyte may include an organic solvent and a lithium salt. The organic solvent serves as a medium through which ions involved in the electrochemical reaction of the battery can move, and is not particularly limited. The electrolyte may be, for example, a carbonate-, ester-, ether-, ketone-, alcohol- or aprotic-based solvent used alone or in combination of two or more, and the mixing ratio in the case of using two or more in combination may be adjusted according to the desired battery performance.The lithium salt may be a substance dissolved in an organic solvent and serving as a source of lithium ions in the battery, enabling basic operation of a lithium secondary battery, and promoting movement of lithium ions between the cathode and the anode. The lithium salt is not particularly limited, and a known substance may be used in a concentration suitable for this purpose. The electrolyte may further contain a known solvent and additive for improving charge / discharge properties, flame retardancy, etc., as needed.In some embodiments, a separator may not be included between the cathode and the anode of the unit cell, but may include a solid electrolyte. The solid electrolyte is not particularly limited. The solid electrolyte may be, for example, an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a polymer-based solid electrolyte.As set forth above, according to an embodiment, a lithium secondary battery with improved safety can be provided.According to one embodiment, occurrence of a venting phenomenon in a lithium secondary battery can be prevented.In one embodiment, a fire can be prevented from being generated in a lithium secondary battery.Only specific example implementations of certain embodiments are described. Variations, improvements, and extensions of the disclosed embodiments and other embodiments may be made based on the disclosure of this specification.

Claims

An electrode for a lithium secondary battery, comprising: an electrode current collector, and an electrode mixture layer and an insulating layer on at least one surface of the electrode current collector, wherein the insulating layer contains an organometallic framework (MOF).The electrode according to claim 1, wherein the metal organic framework (MOF) contains at least one metal selected from the group consisting of aluminum (Al), magnesium (Mg), copper (Cu), zirconium (Zr), cerium (Ce), yttrium (Y), scandium (Sc), molybdenum (Mo), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), cadmium (Cd), calcium (Ca), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), ruthenium (Ru), gadolinium (Gd), europium (Eu), terbium (Tb), zinc (Zn), iron (Fe), and nickel (Ni).The electrode according to claim 1 or 2, wherein the insulating layer further contains at least one polymer material selected from the group consisting of polyimide (PI), polyetherimide (PEI), polyamideimide (PAI), polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC).The electrode according to claim 3, wherein the weight ratio between the metal organic framework (MOF) and the polymer material contained in the insulating layer is 50:50 to 99:1.The electrode according to claim 3 or 4, wherein the content of the polymer material contained in the insulating layer is 1 to 50 wt%.The electrode according to any one of claims 1 to 5, wherein the thickness of the insulating layer is less than or equal to the thickness of the electrode mixture layer.The electrode according to any one of claims 1 to 6, wherein the electrode current collector includes an uncoated part on which the electrode mixture layer is not disposed on the surface, and the insulating layer is disposed on the uncoated part.The electrode according to any one of claims 1 to 7, wherein the electrode current collector includes an uncoated part on which the electrode mixture layer is not disposed on the surface, and the insulating layer is disposed to cover a part of the electrode mixture layer from a part of the uncoated part.The electrode according to any one of claims 1 to 8, wherein the insulating layer includes a first insulating layer on the electrode current collector and a second insulating layer on the first insulating layer.The electrode according to claim 9, wherein the first insulating layer contains an inorganic compound, and the second insulating layer contains an organometallic framework (MOF).The electrode according to claim 10, wherein the inorganic compound contains at least one selected from the group consisting of Al 2 O 3, TiO 2, MgO, CuO, MnO, CoO, CrO, Cr 2 O 3, NiO, ZrO 2, CeO 2, SiO, SiO 2, GeO, GeO 2, Nb 2 O3, and B 2 O 3.The electrode according to any one of claims 9 to 11, wherein the thickness of the first insulating layer is less than or equal to the thickness of the second insulating layer.The electrode according to claim 12, wherein the thickness ratio of the first insulating layer and the second insulating layer is 10:90 to 50:50.The electrode according to any one of claims 9 to 13, wherein the thickness of the first insulating layer is 2 μm to 10 μm.The electrode according to any one of claims 9 to 14, wherein the thickness of the second insulating layer is 10 μm to 18 μm.A lithium secondary battery comprising the electrode according to any one of claims 1 to 15.

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