KR20170032546A - Case for Secondary Battery Comprising Inner Sealant Layer Including Nanaporous Material and Lithium Secondary Battery Comprising the Same - Google Patents

Abstract

The present invention relates to a case for a secondary battery, which is composed of a laminate sheet which includes an outer coating layer, an inner sealant layer, and a barrier layer which is located between the outer coating layer and the inner sealant layer. The inner sealant layer is a coating layer or a porous film which includes porous nanomaterials of an average pore size of 1 to 100 nm. Accordingly, the present invention can prevent the degradation of battery performance due to swelling.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a case for a secondary battery including an inner sealant layer containing a porous nano material, and a lithium secondary battery including the inner sealant layer,

The present invention relates to a case for a secondary battery including an inner sealant layer containing a porous nanomaterial and a lithium secondary battery including the same.

As technology development and demand for mobile devices have increased, there has been a rapid increase in demand for secondary batteries as energy sources. Among such secondary batteries, lithium secondary batteries, which exhibit high energy density and operational potential, long cycle life, Batteries have been commercialized and widely used.

Such a lithium secondary battery is classified into a cylindrical battery, a prismatic battery, a pouch-shaped battery, and the like according to its external shape. Due to the recent tendency toward miniaturization of mobile devices, demand for thin rectangular prismatic batteries and pouch- In particular, there is a high interest in a pouch type battery in which the shape is easily deformed, the manufacturing cost is low, and the weight is small.

Generally, in a pouch type secondary battery, in the state that an electrode assembly having a porous separator interposed between a positive electrode and a negative electrode coated with an active material on a current collector is mounted inside a pouch-shaped battery case, a non-aqueous electrolyte Is impregnated into the structure.

In such a lithium secondary battery, the carbonic ester contained in the non-aqueous liquid electrolyte during the cycle is subject to deterioration or electrolysis due to a rise in temperature inside the battery in the event of repeated charging, discharging, overcharging, short-circuiting or the like. As a result, gas such as CO or CO ₂ is generated in the battery, swelling phenomenon in which the case rises as the internal pressure increases, and the internal resistance is increased.

Furthermore, at high temperatures, the reaction between the lithium transition metal oxide, which is a positive electrode active material, and the electrolyte is promoted, thereby producing a by-product which increases the resistance of the positive electrode.

Specifically, a minute amount of moisture can be contained in the battery in the manufacturing process of the battery and the like. In the case of the pouch type case, the possibility of moisture penetrating through the sealing part is very high. In this case, if the electrolyte contains LiPF ₆ lithium salt, LiPF ₆ should exist in the form of Li ⁺ and PF ₆ ^- , but unlike intention, a side reaction occurs to generate unstable PF ₅ as a byproduct, To form HF. This HF destroys the SEI layer, causing dissolution of the anode or creating vacancies between the electrodes, which is more pronounced at high temperatures.

In connection with this problem, some prior art discloses techniques for incorporating a desired moisture sorbent in a cell. For example, Japanese Patent Application Laid-Open No. 1997-92255 discloses a technique of using a nonwoven fabric composed of ceramic short fibers such as alumina, alumina-silica, potassium titanate (Kalium), etc. as a separator. Korean Patent Application Publication No. 2000-0031096 discloses a technique of adding a molecular sieve or a fumed silica fine powder to an electrode, and Japanese Patent Application Laid-Open No. 2005-235591 discloses a method of adding an additive for reducing the generation of gas in an electrolyte And the like. US 6337153 discloses a closed non-aqueous electrolyte cell in which an electrode or an inorganic acid powder that adsorbs a substance such as hydrofluoric acid or water in an electrolyte is provided inside an external body using a laminate sheet of a metal foil and a resin film have.

However, the above technologies are a technique for incorporating a predetermined inorganic substance into an electrode, a separation membrane, or an electrolyte constituting an electrode assembly in the form of an additive. When the inorganic additive is present in a large amount at a site directly acting on the battery, The mobility is largely lowered, and consequently, the conductivity is lowered, so that the cell performance may be deteriorated and various side reactions may occur in the cell.

Therefore, there is a high need for a secondary battery technology that can effectively improve the safety and lifetime characteristics of a battery by effectively removing gas and moisture generated during a cycle or at a high temperature.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments, and have found that, as will be described later, the inner sealant layer of the secondary battery case is coated with a coating layer containing a porous nano material having an average pore size of 1 to 100 nm It has been found that a desired effect can be achieved without increasing the volume of the battery when the battery is constituted of a porous film, and the present invention has been accomplished.

Therefore, in the secondary battery case according to the present invention,

A laminate sheet comprising an outer coating layer, an inner sealant layer, and a barrier layer positioned between the outer coating layer and the inner sealant layer,

Wherein the inner sealant layer is a coating layer or a porous film containing a porous nanomaterial having an average pore size of 1 to 100 nm.

The porous nanomaterial can more particularly have an average pore size of 1 to 50 nm.

According to the present invention, the coating layer comprising the porous nanomaterial as the inner sealant layer or the porous film can be prevented from being deteriorated due to an abnormality such as repetition, overcharge, or short-circuit of the charge / The swelling phenomenon of swelling of the case and the increase of the internal resistance as the internal pressure is increased by absorbing CO or CO ₂ gas components such as CO ₂ generated by decomposition due to the temperature rise of the battery at a high rate It is possible to prevent the moisture and the side reaction of the electrolytic solution from being able to effectively collect a small amount of moisture generated in the battery and moisture that can permeate from the outside, It is possible to suppress deterioration of battery performance such as capacity.

The inner sealant layer may be a coating layer or a porous film as described above. Specifically, the inner sealant layer may be a coating layer in which a porous nano material is coated on one surface of a barrier layer, a porous nano- A porous film included in the pores or a porous film made of a porous nano material.

The coating layer can be formed by dispersing a porous nanomaterial together with a binder in a solvent to prepare a coating composition, applying the coating composition to one side of the barrier layer, and then drying the coating composition. At this time, the content of the porous nanomaterial, the binder, and the solvent can be appropriately selected in consideration of the binding force, the rigidity, the degree of the desired effect, and the like. When the inner sealant layer is formed as a coating layer, a separate film production process is unnecessary, which is preferable from the viewpoint of process efficiency, and the porous nanomaterials are more firmly bonded by the binder, Thereby reducing the possibility of nanomaterials falling off, thereby reducing the problem of cell safety that can occur.

The porous film in which the porous nanomaterial is contained in the voids of the substrate can be prepared by preparing a separate substrate having a void and dispersing the porous nanomaterial on the substrate. At this time, the content of the porous nanomaterial can be appropriately selected in consideration of the degree of the desired effect and the influence on the cell performance. The thus prepared porous film is then bonded together with the outer coating layer and the barrier layer to form a laminate sheet. The porous film thus produced does not require a separate coating step, but simply involves dispersing and dispersing the porous nanomaterial on the substrate, so that the process is simple, and since separate substrates are used together, it is excellent in terms of mechanical rigidity.

Here, the base material is a porous base material having a large number of voids and a pore diameter of usually 0.01 to 10 占 퐉, and the thickness is generally 10 to 50 占 퐉 because the inner sealant layer is formed. Such substrates include, for example, olefin-based polymers such as polypropylene having chemical resistance and hydrophobicity; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like can be used, but the present invention is not limited thereto.

Finally, a porous film made of a porous nanomaterial can be produced by coating a coating composition obtained by dispersing the porous nanomaterial in a solvent on a base material such as glass by spin coating, drying, and then peeling it from the base material have. At this time, the content of the porous nanomaterial and the solvent can be appropriately selected in consideration of the extent to which the porous nanomaterial can form a film. The thus prepared porous film is then bonded together with the outer coating layer and the barrier layer to form a laminate sheet. The porous film thus produced may be weaker in terms of its bonding force than the above structures. However, since the porous film is made of only porous nano materials and has the best ability to collect gas and moisture, the effect of the present invention can be achieved more effectively have.

As described above, according to the present invention, it is possible to exhibit the intended effect of the present invention even if the porous nanomaterial is not included in the electrolyte solution, the electrode structure, or the like, The existence of the material can lower the lithium ion mobility and consequently decrease the conductivity of the battery, thereby deteriorating the battery performance and solving the problem of causing various side reactions in the battery.

Further, the case for a secondary battery according to the present invention includes a coating layer or a porous film containing a porous nano material as an inner sealant layer, and the porous nano material may be coated on the inner surface of the case, There is an excellent effect in that it can contain more porous material and can hold the collecting ability of more excellent gas and moisture or reduce the case thickness.

Meanwhile, the porous nanomaterial having an average pore size of 1 to 100 nm may be an inorganic material, an organic material, or an organic-inorganic composite material.

More particularly, the present invention relates to a method for manufacturing a semiconductor device, which includes a step of forming a semiconductor layer on a substrate, such as aluminum (Al), titanium (Ti), zinc (Zn), magnesium (Mg), tin (Sn), silicon (Si), indium (In) (C), or an inorganic material or organic material based on at least one material selected from the group consisting of aluminum (Al), titanium (Ti), zinc (Zn), magnesium (Mg), tin Based on at least one material selected from the group consisting of silicon (Si), silicon (Si), indium (In), gallium (Ga), oxygen (O), and carbon (C) Modified inorganic material, organic material or organic-inorganic composite material.

These materials include, for example, porous silica, activated alumina, titanium oxide, magnesium oxide, calcium silicate, magnesium silicate, activated carbon materials, carbon nanotubes, fullerenes, clay mineral materials, montmorillonite materials, zeolite- , A mesoporous-based material, a metal-organic framework (MOF), an organoaluminum compound, an organic titanium compound, an organic silicon compound, an organic zinc compound, an organomagnesium compound, an organic indium compound, These porous nanomaterials may be used alone, or two or more kinds of materials may be used together.

Among these porous nanomaterials, a zeolite-based material, a mesoporous-based material, or a metal-organic framework (MOF) may be more preferably used.

The zeolite-based material may be a material having micropores having a pore size of 2 nm or less, more specifically, natural zeolite or modified zeolite. Here, the natural zeolite is an inorganic material based on silicon (Si) and aluminum (Al), which is represented by (Si, Al) O ₄ , and the modified zeolite is obtained by pretreating, Means a zeolite surface-modified by heat treatment or the like. Examples of ion exchange include ion exchange with Li or Ca, and the like. The zeolite-based materials are not limited as long as they have an ability to collect gas and the like as an effect according to the present invention. Specific examples of the modified zeolite are known in the art, .

The mesoporous-based material is a material having a pore size larger than that of the zeolite-based material and having a mesopore of 2 nm to 50 nm. Examples of such mesoporous materials include mesoporous silica, mesoporous alumina, mesoporous carbon, and the like, each of which may be partially modified with an organic material or an inorganic material of another metal. Thus, the mesoporous material used in the present invention may be, for example, modified or unmodified mesoporous silica, modified or unmodified mesoporous alumina, or modified or unmodified mesoporous carbon, But the present invention is not limited thereto.

As described above, the zeolite and mesoporous-based material as the porous nanomaterial that can be used in the present invention are basically composed of an inorganic material and are excellent in heat resistance. Among them, the modified zeolite modified with the organic material, Silica, modified mesoporous alumina, and inorganic modified mesoporous carbon can secure more chemical resistance than the polypropylene film used as a conventional inner sealant layer, and are superior in stiffness, It is possible to secure the safety of the battery from the chemical reaction and the physical impact acting thereon.

In addition, the metal organic structure is a new type of organic-inorganic composite material that is three-dimensionally bonded as compared with a zeolite-based material having a fine pore or a mesoporous-based material having a mesopore, (2 nm or less) and mesoporous regions (2 to 50 nm), and that the size of the pores is both a micropore region (2 nm or less) and a mesopore region (2 to 50 nm). Therefore, such a metal organic structure has a wide range of molecular sizes that can be collected, and is excellent in the ability to collect gas molecules of various sizes existing in the cell.

From these properties, various porous nanomaterials can be selected depending on the purpose.

On the other hand, as the other constitution of the laminate sheet, the outer coating layer is made of a weather-resistant polymer having a predetermined tensile strength and weather resistance because it has excellent resistance to external environment, and the weather-resistant polymer is polyethylene terephthalate (PET) Phthalate (PEN) or nylon.

The barrier layer may be a metal layer in one specific example so as to exhibit a function of improving the strength of the case in addition to the function of preventing the inflow or outflow of foreign matter such as gas or moisture, (Al), Fe, Cu, Sn, Ni, Co, Ag, stainless steel, carbon, chromium, , Manganese (Mn), and titanium (Ti), or an alloy thereof, but is not limited thereto.

The present invention also provides a secondary battery comprising the secondary battery case, the electrode assembly, and the electrolyte, wherein the secondary battery is not particularly limited, and in particular, an electrolyte solution containing a lithium salt is impregnated into the electrode assembly , So-called lithium secondary batteries.

The electrode assembly is composed of an anode and a cathode so that charging and discharging can be performed. For example, a structure in which an anode and a cathode are stacked with a separator interposed therebetween may be a folding (jelly-roll) Folding type. The positive electrode and the negative electrode of the electrode assembly may have a shape in which the electrode tab protrudes directly out of the battery, or the electrode tab may be connected to a separate lead to protrude to the outside of the battery.

The anode is prepared by applying a mixture of a cathode active material, a conductive material and a binder on a cathode current collector, followed by drying and pressing. If necessary, a filler may be further added to the mixture.

The cathode current collector generally has a thickness of 3 to 500 mu m. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery. Examples of the positive electrode current collector include stainless steel, aluminum, nickel, titanium, sintered carbon, aluminum or stainless steel A surface treated with carbon, nickel, titanium, silver or the like may be used. The current collector may have fine irregularities on the surface thereof to increase the adhesive force of the cathode active material, and various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric are possible.

The cathode active material may be a layered compound such as lithium cobalt oxide (LiCoO ₂ ), lithium nickel oxide (LiNiO ₂ ), or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li _{1 + x} Mn _{2 -x} O ₄ (where x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , LiMnO ₂ and the like; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ and Cu ₂ V ₂ O ₇ ; A Ni-site type lithium nickel oxide expressed by the formula LiNi _1-x M _x O ₂ (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0.3); Formula _{LiMn 2-x M x O 2} ( where, M = Co, Ni, Fe , Cr, and Zn, or Ta, x = 0.01 ~ 0.1 Im) or Li ₂ Mn ₃ MO ₈ (where, M = Fe, Co, Ni, Cu, or Zn); A lithium manganese composite oxide having a spinel structure represented by LiNi _x Mn _2-x O ₄ ; LiMn ₂ O _{4 in} which a part of Li in the formula is substituted with an alkaline earth metal ion; Disulfide compounds; Fe ₂ (MoO ₄ ) ₃ , But the present invention is not limited to these.

The conductive material is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture including the cathode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The binder is a component which assists in bonding of the active material and the conductive material and bonding to the current collector, and is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture containing the cathode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , Polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, fluorine rubber, various copolymers and the like.

The filler is optionally used as a component for suppressing the expansion of the anode, and is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery. Examples of the filler include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The negative electrode is prepared by coating, drying and pressing the negative electrode active material on the negative electrode current collector, and may optionally further include a conductive material, a binder, a filler, and the like as described above.

The negative electrode current collector is generally made to have a thickness of 3 to 500 mu m. Such an anode current collector is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, and examples of the anode current collector include copper, stainless steel, aluminum, nickel, titanium, sintered carbon, a surface of copper or stainless steel A surface treated with carbon, nickel, titanium, silver or the like, an aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

The negative electrode active material may include, for example, carbon such as non-graphitized carbon or graphite carbon; _{Li x Fe 2 O 3 (0≤x≤1} ), Li x WO 2 (0≤x≤1), Sn x Me 1-x Me 'y O z (Me: Mn, Fe, Pb, Ge; Me' : Metal complex oxides such as Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, Halogen, 0 < x &lt; Lithium metal; Lithium alloy; Silicon-based alloys; Tin alloy; _{SnO, SnO 2, PbO, PbO} 2, Pb 2 O 3, Pb 3 O 4, Sb 2 O 3, Sb 2 O 4, Sb 2 O 5, GeO, GeO 2, Bi 2 O 3, Bi 2 O 4, And Bi ₂ O ₅ ; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like can be used.

The separation membrane is interposed between the anode and the cathode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the separator is generally 0.01 to 10 mu m and the thickness is generally 5 to 300 mu m. Such separation membranes include, for example, olefinic polymers such as polypropylene, which are chemically resistant and hydrophobic; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The electrolyte may be a non-aqueous electrolyte containing a lithium salt. The non-aqueous electrolyte containing the lithium salt is composed of a non-aqueous electrolyte and a lithium salt. Non-aqueous organic solvents, organic solid electrolytes, inorganic solid electrolytes, But is not limited thereto.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , Acetonitrile, nitromethane, methyl formate, methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate Nonionic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyrophosphate, ethyl propionate and the like can be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, A polymer containing an ionic dissociation group and the like may be used.

Examples of the inorganic solid electrolyte include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides and sulfates of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ can be used.

The lithium salt is a material that is readily soluble in the non-aqueous electrolyte, for example, LiCl, LiBr, LiI, LiClO 4, LiBF 4, LiB 10 Cl 10, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF _{6, LiSbF 6, LiAlCl 4,} CH 3 SO 3 Li, (CF 3 SO 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide.

For the purpose of improving the charge / discharge characteristics and the flame retardancy, the electrolytic solution is preferably mixed with an organic solvent such as pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, Benzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, . In some cases, halogen-containing solvents such as carbon tetrachloride and ethylene trifluoride may be further added to impart nonflammability. In order to improve the high-temperature storage characteristics, carbon dioxide gas may be further added. FEC (Fluoro-Ethylene Carbonate, PRS (Propene sultone), and the like.

In one specific _{example, LiPF 6, LiClO 4, LiBF} 4, LiN (SO 2 CF 3) 2 , such as a lithium salt, a highly dielectric solvent of DEC, DMC or EMC Fig solvent cyclic carbonate and a low viscosity of the EC or PC of To a mixed solvent of linear carbonate to prepare a nonaqueous electrolyte solution containing a lithium salt.

The present invention further provides a battery module including the secondary battery, a battery pack including the battery module, and a device including the battery pack.

Specific examples of the device include a mobile phone, a portable computer, a smart phone, a tablet PC, a smart pad, a netbook, a light electronic vehicle (LEV), a power tool powered by an electric motor, An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and the like; An electric motorcycle including an electric bike (E-bike) and an electric scooter (E-scooter); An electric golf cart; And a power storage device, but the present invention is not limited thereto.

Such a battery module, a battery pack, and a structure and a manufacturing method of the device are well known in the art, so a detailed description thereof will be omitted herein.

As described above, the case for a secondary battery according to the present invention is characterized in that the inner sealant layer of the laminate sheet composed of the outer coating layer, the inner sealant layer, and the barrier layer positioned between the outer coating layer and the inner sealant layer has a thickness of 1 to 100 nm or a porous nano material having a mean pore size of 1 nm or less and a porous nano material having a mean pore size of 1 nm or less, the gas and moisture which may be generated during the cycle or during high-temperature storage can be easily and easily It is possible to solve problems such as increase in cell thickness due to swelling, ignition, deterioration in battery performance and deterioration in lifetime characteristics, and the like.

In addition, when a porous nano material including an inorganic material is included, heat resistance is excellent, and chemical resistance and rigidity can be improved through modification of the porous nano material. Therefore, the secondary battery, The safety can be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view partially showing a method of manufacturing a laminate sheet for a secondary battery case according to an embodiment of the present invention and a resultant product;
2 is a schematic view partially showing a method of manufacturing a laminate sheet for a secondary battery case according to another embodiment of the present invention and the resultant product;
3 is a schematic view partially showing a method of producing a laminated sheet for a secondary battery case according to another embodiment of the present invention and the resultant product;

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

1 to 3 are schematic views for explaining a method of manufacturing a laminate sheet for a secondary battery case according to an embodiment of the present invention, and also schematic sectional views of the resulting structure are shown .

1, a laminate sheet for forming a case for a secondary battery according to an embodiment of the present invention is a laminate sheet having a structure in which an outer coating layer 110 and a barrier layer 120 are bonded, A coating composition 140 in which a binder and a porous nanomaterial are dispersed in a solvent is coated on the one surface and then the solvent is dried to form a coating layer 130 as an inner sealant layer.

The inner sealant layer of the laminate sheet thus produced is formed by coating the porous nano material 131 with the binder 132 on one side of the barrier layer 120 to form a coating layer 130 having an average pore size of 1 to 100 nm, .

2 and 3, a method of manufacturing a laminate sheet for a secondary battery case according to another embodiment of the present invention is a method of manufacturing an inner sealant layer as a single film including a porous nano material Are schematically shown.

Referring to FIG. 2, a glass 201 is first prepared, a coating composition 240 in which a porous nanomaterial is dispersed in a solvent is coated on a glass 201, and then dried. When the coating composition 240 in which the porous nanomaterial is dispersed in the solvent is dried, the porous nanomaterial 231 is made into a 2D or 3D porous film. Thereafter, the laminate sheet is peeled from the glass 201, and the outer cover layer 210, the barrier layer 220, and the porous film 230 are laminated in order and bonded to each other.

Here, the coating composition in which the porous nanomaterial is dispersed in a solvent is a sol, and the composition is applied to a glass by spin coating or the like. At this time, the porous nanomaterial in the composition has a 2D or 3D structure between nano materials through networking, so that the composition coated on a glass can be dried to form a film.

Also, referring to FIG. 3, there is shown a method of manufacturing a laminate sheet with a porous film containing a porous nanomaterial without a separate coating process.

A porous nano material 331 is dispersed in the void of the substrate 301 by preparing a substrate 301 having a void capable of dispersing the porous nano material and spraying a porous nano material 331 on the substrate 301, The porous film 330 as an inner sealant layer is produced. Thereafter, the outer cover layer 310, the barrier layer 320, and the porous film 330 are laminated in order and bonded to each other to produce a laminate sheet.

The case for a secondary battery made of the laminate sheet thus manufactured is characterized in that the innermost inner sealant layer contains a porous nanomaterial having an average pore size of 1 to 100 nm, It is possible to solve problems such as increase in cell thickness due to swelling, deterioration in battery performance, deterioration in life characteristics, and the like by effectively and easily removing gas and moisture that may be generated in a short time.

However, the present invention is not limited to the structure used for the laminate sheet manufactured by the method as described above. If the case for the secondary battery having the structure in which the inner sealant layer includes the porous nanomaterial is used, Of course.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (17)

A laminate sheet comprising an outer coating layer, an inner sealant layer, and a barrier layer positioned between the outer coating layer and the inner sealant layer,
Wherein the inner sealant layer is a coating layer or a porous film comprising a porous nanomaterial having an average pore size of 1 to 100 nm. The secondary battery case according to claim 1, wherein the inner sealant layer is a coating layer in which a porous nano material is coated on one surface of a barrier layer. The secondary battery case according to claim 2, wherein the inner sealant layer is a porous film comprising a porous nano material in a void of the base material or a porous film made of a porous nano material. The case for a secondary battery according to claim 1, wherein the porous nanomaterial is an inorganic material, an organic material, or an organic-inorganic composite material. The method of claim 1, wherein the porous nanomaterial is selected from the group consisting of aluminum (Al), titanium (Ti), zinc (Zn), magnesium (Mg), tin (Sn), silicon (Si), indium (In) , Oxygen (O), and carbon (C) based on at least one material selected from the group consisting of an inorganic material and an organic material. The method of claim 1, wherein the porous nanomaterial is selected from the group consisting of aluminum (Al), titanium (Ti), zinc (Zn), magnesium (Mg), tin (Sn), silicon (Si), indium (In) Inorganic composite material based on at least one substance selected from the group consisting of oxygen (O), carbon (C), and a part of which is modified with another metal or an organic material The secondary battery case is characterized by. The secondary battery case according to claim 1, wherein the porous nanomaterial is a zeolite-based material, a mesoporous-based material, or a metal-organic framework (MOF). The secondary battery case according to claim 7, wherein the zeolite-based material is natural zeolite or modified zeolite. The secondary battery case according to claim 7, wherein the mesoporous material is modified or unmodified mesoporous silica, modified or unmodified mesoporous alumina, or modified or unmodified mesoporous carbon. The secondary battery case according to claim 1, wherein the outer coating layer is made of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or nylon. The secondary battery case according to claim 1, wherein the barrier layer is a metal layer. 12. The method of claim 11, wherein the metal layer is formed of a material selected from the group consisting of Al, Fe, Cu, Sn, Ni, Co, Ag, , Carbon (C), chromium (Cr), manganese (Mn), and titanium (Ti) or an alloy thereof. A secondary battery comprising the secondary battery cell case according to claim 1, an electrode assembly, and an electrolyte. A battery module comprising the secondary battery according to claim 13. A battery pack comprising the battery module according to claim 14. A device comprising a battery pack according to claim 15. 17. The method of claim 16, wherein the device is selected from the group consisting of a mobile phone, a portable computer, a smart phone, a tablet PC, a smart pad, a netbook, a LEV (Light Electronic Vehicle), an electric vehicle, a hybrid electric vehicle, &Lt; / RTI &gt; device.

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