Secondary battery having an anti-corrosion layer on the inner surface of the battery case

Abstract

The present disclosure provides a secondary battery in which an anti-corrosion layer of an organic / inorganic hybrid layer is formed on a portion of an inner surface of a battery case of a cylindrical secondary battery and a battery case of a prismatic secondary battery.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0140607, filed on October 27, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

[0003] The present disclosure relates to a secondary battery having an anti-corrosion layer formed on an inner surface of a battery case. Background Art

[0004] Due to the rapid increase in the use of fossil fuels, the demand for the use of alternative energy or clean energy is increasing, and as a part of this, the most active field of research is the field of power generation and energy storage using electrochemistry.

[0005] Currently, secondary batteries are a representative example of electrochemical devices utilizing such electrochemical energy, and the range of use of secondary batteries tends to gradually expand.

[0006] Recently, with the technological development and increased demand for mobile devices such as laptops, mobile phones, and cameras, the demand for secondary batteries as energy sources has also increased dramatically. Among such secondary batteries, lithium secondary batteries, which have been widely studied and are now commercialized and widely used, exhibit high charge / discharge characteristics and life characteristics and are environmentally friendly.

[0007] Generally, a secondary battery has a structure in which an electrode assembly including a positive electrode, a negative electrode, and a porous separator is incorporated in a battery case in a state of being impregnated with a nonaqueous electrolyte.

[0008] In this case, according to the shape of the battery case, secondary batteries can generally be divided into cylindrical secondary batteries or prismatic secondary batteries in which a stacked / folded or wound electrode assembly is accommodated in a shell made of metal as a battery shell, pouch-type secondary batteries in which a stacked or stacked / folded electrode assembly is incorporated in a pouch-type battery shell made of an aluminum laminate, and coin-type batteries in which a coin-type electrode assembly is accommodated in an upper shell and a lower shell made of metal.

[0009] In the case of prismatic batteries, cylindrical batteries, or coin-type batteries, since metal rather than polymer is used as the outer material, metal corrosion may occur depending on the type of electrolyte solution. Therefore, there are limitations on the electrolyte solutions that can be used, and in particular, there is a problem that corrosion is extremely severe in electrolyte solutions using imide-based salts.

[0010] Therefore, there is a need to develop a technology for a secondary battery that can solve the above problems and effectively prevent corrosion of a metal can regardless of the type of electrolyte. Summary of the Invention

[0011] Technical issues

[0012] The present disclosure is made to solve the above-mentioned problems and other technical problems that have yet to be resolved.

[0013] Specifically, an object of the present disclosure is to provide a secondary battery that can effectively suppress corrosion of a secondary battery case due to contact with an electrolyte solution.

[0014] Technical Solution

[0015] To achieve the above object, according to one embodiment of the present disclosure, there is provided a cylindrical secondary battery configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is accommodated in a battery case together with an electrolyte solution,

[0016] The battery housing is made of metal and includes

[0017] a cylindrical can comprising a housing portion in which an electrode assembly is housed together with an electrolyte solution and a beading portion located above the housing portion; and a cap assembly mounted on an open upper end portion of the cylindrical can and comprising an upper end cap serving as a protruding electrode terminal, and

[0018] The anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the accommodation portion where the battery case contacts the electrolyte solution, or on the inner surfaces of the accommodation portion and the beading portion.

[0019] At this time, the metal may be composed of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass.

[0020] Furthermore, the electrode assembly may be a wound-type electrode assembly or a stacked / folded-type electrode assembly.

[0021] More specifically, the gasket is installed on the upper portion of the curled edge of the cylindrical tank.

[0022] The cover assembly is configured so that a safety device for current interruption (PTC device) and a safety vent for internal pressure drop are stacked below the upper end cover, and a current interrupt device (CID) is formed at the lower end of the safety vent.

[0023] The electrode assembly includes a positive electrode tab and a negative electrode tab led out of the electrode assembly, wherein the positive electrode tab is connected to the cap assembly, and the negative electrode tab is connected to the bottom surface spaced apart from the receiving portion of the cylindrical can, and

[0024] An anti-corrosion layer may be formed on a surface of the gasket facing the inner surface of the secondary battery.

[0025] In a specific embodiment, the secondary battery further includes a hollow center pin inserted into the center portion of the electrode assembly, and the anti-corrosion layer may be further formed on an outer surface where the center pin and the electrolyte solution contact each other.

[0026] Furthermore, the corrosion-resistant layer is formed even on the hollow inner surface of the center pin.

[0027] At this time, the center pin may be made of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass.

[0028] The organic-inorganic hybrid layer may comprise one or more inorganic particles and a binder polymer, wherein the one or more inorganic particles are selected from: (a) inorganic particles having a dielectric constant of 1 or greater, (b) inorganic particles having piezoelectricity, (c) thermally conductive inorganic particles, and (d) inorganic particles having lithium ion transport capability.

[0029] Meanwhile, according to another embodiment of the present disclosure, there is provided a prismatic secondary battery configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution,

[0030] The battery housing is made of metal and includes

[0031] a rectangular can body that is open at its upper end and houses the electrode assembly together with the electrolyte solution; and a top cover that includes a cover terminal that is coupled and sealed to the upper end portion of the can body and connected to the electrode terminal of the electrode assembly, and

[0032] The anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the can body where the battery case contacts the electrolyte solution, or on the inner surface of the can body and the inner surface of the top cover excluding the cover terminal.

[0033] At this time, the metal may be composed of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass.

[0034] The electrode assembly may be a wound-type electrode assembly or a stacked / folded-type electrode assembly.

[0035] The electrode assembly includes a positive electrode tab and a negative electrode tab led out therefrom, and the positive electrode tab and the negative electrode tab may be connected to the cap terminals, respectively.

[0036] In a specific embodiment, the prismatic secondary battery further includes a hollow center pin inserted into the center portion of the electrode assembly, and the anti-corrosion layer may be further formed on an outer surface where the center pin and the electrolyte solution contact each other.

[0037] The corrosion-resistant layer may even be formed on the hollow inner surface of the center pin.

[0038] At this time, the center pin may be made of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass.

[0039] The organic-inorganic hybrid layer may comprise one or more inorganic particles and a binder polymer, wherein the one or more inorganic particles are selected from: (a) inorganic particles having a dielectric constant of 1 or greater, (b) inorganic particles having piezoelectricity, (c) thermally conductive inorganic particles, and (d) inorganic particles having lithium ion transport capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of a cylindrical secondary battery according to one embodiment of the present disclosure; and

[0041] Figure 2 is a schematic diagram of a prismatic secondary battery according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0042] Hereinafter, the present disclosure will be described in more detail for better understanding of the present disclosure.

[0043] The terms or words used in this specification and claims should not be construed as limited to common terms or dictionary terms, and the present disclosure should be interpreted with meanings and concepts consistent with the technical ideas of the present disclosure based on the principle that the inventor can appropriately define the concepts of the terms in order to appropriately describe his own disclosure in the best manner.

[0044] The technical terms provided herein are only used for the purpose of describing specific embodiments and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms as well.

[0045] Furthermore, throughout the specification, when a part is referred to as “including” a certain component, unless otherwise specified, this means that the part may further include other components, rather than excluding other components.

[0046] According to one embodiment of the present disclosure,

[0047] A cylindrical secondary battery may be provided, the cylindrical secondary battery being configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution,

[0048] The battery housing is made of metal and includes

[0049] a cylindrical can comprising a housing portion in which an electrode assembly is housed together with an electrolyte solution and a curling portion located above the housing portion; and a cap assembly mounted on an open upper end portion of the cylindrical can and comprising an upper end cap serving as a protruding electrode terminal, and

[0050] The anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the accommodation portion where the battery case contacts the electrolyte solution, or on the inner surfaces of the accommodation portion and the beading portion.

[0051] In this case, the metal constituting the battery case may be composed of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass. Specifically, the metal may be composed of aluminum or stainless steel (SUS), more specifically, the metal may be composed of stainless steel (SUS).

[0052] The degree of corrosion of these metals is severe depending on which material is used as the electrolyte solution, life characteristics are deteriorated, or it will no longer be usable, or safety may be threatened.

[0053] Therefore, the present disclosure is characterized in that, in a secondary battery in which a battery case is made of metal, an anti-corrosion layer is formed on an inner surface in which the battery case contacts an electrolyte solution to prevent corrosion due to the electrolyte solution.

[0054] That is, in a cylindrical secondary battery, the inner surface of the accommodation part is a portion directly and completely exposed to the electrolyte solution, and when the anti-corrosion layer is formed on the inner surface, corrosion due to the electrolyte solution can be effectively suppressed and prevented.

[0055] In this disclosure, Figure 1 A schematic diagram of a cylindrical secondary battery in which such an anti-corrosion layer is formed is shown.

[0056] Reference Figure 1The secondary battery 100 according to the present disclosure is configured such that an electrode assembly 120 including a positive electrode, a separator, and a negative electrode is housed together with an electrolyte solution in a cylindrical can 110 serving as a battery case. The cylindrical can 110 includes a housing 111 and a beaded portion 112, wherein a cap assembly 130 including an upper end cap 131 is located at the open upper end of the cylindrical can 110 and seals the cylindrical can 110. An anti-corrosion layer 160 is formed on the inner surface of the housing 111 in which the electrode assembly 120 is housed, or on the inner surfaces of the housing 111 and the beaded portion 112.

[0057] Here, the accommodation portion 111 is a portion in which the electrode assembly 120 is incorporated, which is separated from a bottom surface 113 of a below-described cylindrical can 110 positioned to be spaced apart from the electrode assembly.

[0058] In this case, the electrode assembly 120 may be a wound type electrode assembly or a stacked / folded type electrode assembly, but is not limited thereto.

[0059] The wound-type electrode assembly is manufactured by inserting a sheet-type separator between a sheet-type positive electrode and a sheet-type negative electrode and winding them.

[0060] The stacked / folded type electrode assembly is manufactured by arranging unit electrodes, full cells stacked so that electrodes having the same polarity are located at both ends, and bicells stacked so that electrodes having different polarities are located at both ends on a sheet-type separator and winding them.

[0061] Detailed configurations of the wound-type electrode assembly and the stacked / folded-type electrode assembly are generally known, and thus a detailed description thereof will be omitted here.

[0062] More specifically, the secondary battery 100 according to the present disclosure includes a gasket 140 mounted on the upper portion of the curling portion 112 of the cylindrical can 110, and is formed into a structure in which the cover assembly 130 includes an upper end cover 131, a current interruption safety device (PTC device) 132 stacked below the upper end cover 131 and a safety vent 133 for internal pressure drop, and a current interruption device (CID) 134 formed at the lower end of the safety vent 133.

[0063] Furthermore, a positive electrode tab 121 and a negative electrode tab 122 are drawn out from the electrode assembly 120 , the positive electrode tab 121 is connected to the cap assembly 130 , and the negative electrode tab 122 is connected to the bottom surface 113 of the cylindrical can 110 spaced apart from the accommodation portion 111 .

[0064] Here, the current interruption safety device 132 , the safety vent 133 , and the current interruption device 134 are preferably structures through which current flows, and they are formed to ensure the safety of the secondary battery.

[0065] Since other specific contents are generally known, their description will be omitted here.

[0066] In addition, the current interruption safety device 132, the safety vent 133, the current interruption device 134, the upper end cover 131 serving as the positive terminal, the bottom surface 113 of the cylindrical can serving as the negative terminal, and the positive and negative tabs 121 and 122 preferably have conductivity.

[0067] Therefore, the anti-corrosion layer of the organic-inorganic hybrid layer cannot be formed on the inner surfaces of these components.

[0068] That is, it is preferable that the anti-corrosion layer be formed on a portion where such conductivity is not required.

[0069] Specifically, preferably, the anti-corrosion layer 160 is formed on the inner surface of the accommodating portion, or the inner surfaces of the accommodating portion and the curling portion. Since the gasket does not require such conductivity, the anti-corrosion layer 160 can even be formed on the surface of the gasket facing the inner surface of the secondary battery.

[0070] Meanwhile, a layer may not be formed on the surfaces of the upper end cover 131, the bottom surface 113 of the cylindrical can, the current interruption safety device 132, the safety vent 133, the current interruption device 134, the positive electrode tab 121, and the negative electrode tab 122 facing the inner surface of the secondary battery 100, but more preferably, in order to prevent corrosion due to leakage of the electrolyte solution while maintaining conductivity, a conductive layer 170 containing a conductive material that can prevent corrosion and is also conductive may also be formed.

[0071] On the other hand, in addition, the secondary battery 100 according to the present disclosure may further include a hollow center pin 150 inserted into the central portion of the wound-type electrode assembly 120 .

[0072] At this time, the center pin 150 may also be made of any one selected from metals, specifically, aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass, which thus causes corrosion of the electrolyte.

[0073] Therefore, although the outer and inner surfaces of the center pin are not clearly shown in the drawings, an anti-corrosion layer 180 may be further formed in the outer surface of the center pin 150 in contact with the electrolyte solution, and more specifically, the anti-corrosion layer 180 may be formed to the hollow inner surface.

[0074] In another embodiment, a prismatic secondary battery is provided, which is configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution.

[0075] The battery housing is made of metal and includes

[0076] a rectangular can body that is open at its upper end and houses the electrode assembly together with the electrolyte solution; and a top cover that includes a cover terminal that is coupled and sealed to the upper end portion of the can body and connected to the electrode terminal of the electrode assembly, and

[0077] The anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the can body where the battery case contacts the electrolyte solution, or on the inner surface of the can body and the inner surface of the top cover excluding the cover terminal.

[0078] At this time, the metal constituting the battery case may be composed of any one selected from aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass. Specifically, the metal may be composed of aluminum or stainless steel (SUS), and more specifically, the metal may be stainless steel (SUS).

[0079] That is, similar to the cylindrical shape, even in a prismatic secondary battery, the inner surface of the can body is directly and completely exposed to the electrolyte solution. When the anti-corrosion layer is formed on the inner surface, corrosion due to the electrolyte solution can be effectively suppressed and prevented. In addition, the top cover can also be formed with an anti-corrosion layer in the portion other than the cover terminal where conductivity is required.

[0080] In this disclosure, Figure 2 A schematic diagram of a prismatic secondary battery having such an anti-corrosion layer is shown in FIG.

[0081] Reference Figure 2 According to the present disclosure, the secondary battery 200 includes a rectangular can body 210, which is open at its upper end and accommodates an electrode assembly 220 together with an electrolyte solution; and a top cover 230, which includes a cover terminal 231, which is coupled and sealed to the upper end portion of the can body 210 and connected to the electrode terminals of the electrode assembly 220, namely, a positive electrode tab 221 and a negative electrode tab 222.

[0082] At this time, the anti-corrosion layers 250 and 260 are formed on the inner surface of the can body 210 , or the inner surface of the can body 210 and the inner surface of the top cover 230 excluding the cover terminal 231 .

[0083] Here, the electrode assembly 220 may be, but is not limited to, a wound-type electrode assembly or a stacked / folded-type electrode assembly as described for the cylindrical secondary battery.

[0084] In addition, the electrode assembly 220 includes a positive electrode tab 221 and a negative electrode tab 222 drawn out from an upper portion of the electrode assembly 220 , and each of the positive electrode tab 221 and the negative electrode tab 222 has a structure connected to the cap terminal 231 .

[0085] At this time, since the positive electrode tab 221, the negative electrode tab 222 and the cover terminal 231 must have conductivity, no anti-corrosion layers 250 and 260 can be formed and no layer can be formed, but preferably, in order to prevent corrosion due to leakage of the electrolyte solution while maintaining conductivity, a conductive layer 270 containing a conductive material that can prevent corrosion and is conductive can also be formed.

[0086] In addition, the secondary battery 200 according to the present invention may further include a hollow center pin 240 inserted into the center portion of the wound-type electrode assembly 220 .

[0087] At this time, the center pin 240 may also be made of any one selected from metals, specifically, aluminum, nickel, stainless steel (SUS), copper, iron, bronze, and brass, which thus causes corrosion of the electrolyte solution.

[0088] Therefore, although the outer and inner surfaces of the center pin are not clearly shown in the drawings, the anti-corrosion layer 280 may be further formed, and more specifically, the anti-corrosion layer 280 may be formed to the hollow inner surface.

[0089] That is, even in the prismatic secondary battery, the anti-corrosion layers 260 and 280 are formed in portions that may come into contact with the electrolyte solution, thereby effectively preventing corrosion due to contact with the electrolyte solution.

[0090] at the same time, Figure 1 and Figure 2 The configuration of a cylindrical secondary battery and a prismatic secondary battery according to one embodiment is shown, but in cylindrical secondary batteries and prismatic secondary batteries having various structures, if an anti-corrosion layer is formed on a member that does not require conductivity, it goes without saying that they are all included in the scope of the present disclosure.

[0091] Meanwhile, the organic-inorganic hybrid layer as a material constituting the anti-corrosion layer comprises one or more inorganic particles and a binder polymer, wherein the one or more inorganic particles are selected from: (a) inorganic particles having a dielectric constant of 1 or greater, (b) inorganic particles having piezoelectricity, (c) thermally conductive inorganic particles, and (d) inorganic particles having lithium ion transport capability.

[0092] Inorganic particles with piezoelectricity are insulators under normal pressure, but when a certain pressure is applied, they refer to materials that have the physical property of conductivity due to changes in their internal structure. Inorganic particles not only exhibit a high dielectric constant property with a dielectric constant of 100 or more, but also generate charges when stretched or compressed by applying a certain pressure, such that one side is positively charged and the other side is negatively charged, thus having the function of generating a potential difference between the two surfaces.

[0093] Examples of inorganic particles with piezoelectricity include BaTiO3, Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3 (PLZT), PB(Mg3Nb 2 / 3 )O3 - PbTiO3 (PMN - PT) hafnium dioxide (HfO2), or mixtures thereof, etc., but not limited thereto.

[0094] Inorganic particles with lithium ion transport ability refer to inorganic particles that contain lithium element but have the function of enabling lithium ions to move without storing lithium.

[0095] Examples of inorganic particles with lithium ion transport ability include lithium phosphate (Li3PO4), lithium titanium phosphate (Li x Ti y (PO4)3, 0 < x < 2, 0 < y < 3), lithium aluminum titanium phosphate (Li x Al y Ti z (PO4)3, 0 < x < 2, 0 < y < 1, 0 < z < 3), glass based on (LiAlTiP) x O y (0 < x < 4, 0 < y < 13) such as 14Li2O - 9Al2O3 - 38TiO2 - 39P2O5, lanthanum lithium titanate (Li x La y TiO3, 0 < x < 2, 0 < y < 3), lithium germanium thiophosphate (Li x Ge y P z S w , 0 < x < 4, 0 < y < 1, 0 < z < 1, 0 < w < 5) such as Li 3.25 Ge 0.25 P< $ 0.75 S4, lithium nitride (Li x N y , 0 < x < 4, 0 < y < 2) such as Li3N, glass based on SiS2 (Li x Si y S z, 0 < x < 3, 0 < y < 2, 0 < z < 4), for example, Li3PO4 - Li2S - SiS2, P2S5-based glass (Li x P y S z , 0 < x < 3, 0 < y < 3, 0 < z < 7), for example, LiI - Li2S - P2S5, or mixtures thereof, but not limited thereto.

[0096] In addition, examples of inorganic particles having a dielectric constant of 1 or greater include SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiC, or mixtures thereof, but not limited thereto.

[0097] Thermally conductive inorganic particles are materials that provide low heat resistance but do not provide conductivity and thus have insulating properties, and examples thereof may be one or more selected from aluminum nitride (AlN), boron nitride (BN), alumina (Al2O3), silicon carbide (SiC), and beryllium oxide (BeO), but not limited thereto.

[0098] Inorganic particles having a high dielectric constant, inorganic particles having piezoelectricity, thermally conductive mineral particles, and inorganic particles having lithium ion transport ability as described above may also be used in combination.

[0099] The size of the inorganic particles is not limited, but is preferably in the range of 0.001 μm to 10 μm as much as possible to ensure appropriate porosity between the inorganic particles. If the size is less than 0.001 μm, the dispersibility decreases, and it becomes difficult to adjust the physical properties when preparing the organic - inorganic hybrid layer. If the size exceeds 10 μm, the thickness increases, the mechanical properties deteriorate, and it does not play a sufficient role in corrosion protection due to the overly large pore size, and the possibility of internal short - circuit during battery charging and discharging increases.

[0100] The content of the inorganic particles is not particularly limited, but based on a mixture of 100% by weight of the inorganic particles and the binder polymer, the content of the inorganic particles is preferably in the range of 1% to 99% by weight, particularly preferably 10% to 95% by weight. If the content is less than 1%, the content of the polymer becomes too large, and the pore size and porosity may be reduced due to the reduction of the void space formed between the inorganic particles. Conversely, if the content exceeds 99%, the polymer content is too small, weakening the adhesion between the inorganic substances, and ultimately deteriorating the mechanical properties.

[0101] In this case, the pore size and porosity can be adjusted simultaneously by adjusting the size and content of the inorganic particles.

[0102] In addition, the organic-inorganic hybrid layer made of inorganic particles and a binder polymer is robust even under high-temperature conditions due to the heat resistance of the inorganic particles. Therefore, the organic-inorganic hybrid layer is effective in preventing short circuits even under extreme conditions caused by internal or external factors such as high temperature, overcharging, and external impact, and can delay thermal runaway due to the endothermic effect of the inorganic particles.

[0103] The binder polymer is not limited as long as it does not cause a side reaction with the electrolyte solution. In particular, a glass transition temperature (Tg) as low as possible can be used, and the glass transition temperature (Tg) is preferably within a range of -200°C to 200°C.

[0104] Examples of such binder polymers include polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinyl pyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, or a mixture thereof, but are not limited thereto. Any material may be used alone or in combination as long as it has the above-mentioned properties.

[0105] On the other hand, the thickness of the anti-corrosion layer may be 0.01 μm to 100 μm, specifically 0.5 μm to 30 μm, more specifically 1 μm to 10 μm, and most specifically 3 μm to 7 μm.

[0106] If the thickness of the anti-corrosion layer is too thin and outside the above range, it is difficult to fully suppress the corrosion of the metal shell, and if the thickness of the anti-corrosion layer is too thick, good conductivity cannot be obtained or the size may become too large and battery assembly may become difficult, so this is not preferred.

[0107] On the other hand, since the detailed configuration of the electrode assembly of the present disclosure and the specific specifications of the positive electrode, the negative electrode, the separator, and the electrolyte solution are generally known, a detailed description will be omitted here.

[0108] However, the electrolyte solution includes a non-aqueous electrolyte solution and a lithium salt, wherein the secondary battery according to the present disclosure is more efficient when a lithium imide-based salt is used as the lithium salt.

[0109] The lithium imide-based salt may be lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, or lithium bis(perfluoroethylsulfonyl)imide, and preferably, the lithium imide-based salt is lithium bis(fluorosulfonyl)imide or lithium bis(trifluoromethanesulfonyl)imide.

[0110] Based on the above disclosure, those skilled in the art will understand that various applications and modifications are possible within the scope and spirit of the present disclosure.

[0111] Industrial Applicability

[0112] As described above, since the secondary battery according to the present disclosure has the anti-corrosion layer formed on the inner surface of the battery case capable of contacting the electrolyte solution, corrosion due to the electrolyte solution may be effectively prevented and / or suppressed.

Claims

1. A cylindrical secondary battery configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution, The battery housing is made of metal and includes a cylindrical can comprising a housing portion in which the electrode assembly is housed together with the electrolyte solution and a curling portion located above the housing portion; and a cap assembly mounted on the open upper end portion of the cylindrical can and comprising an upper end cap serving as a protruding electrode terminal, and wherein the anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the accommodating portion where the battery case contacts the electrolyte solution, or on the inner surfaces of the accommodating portion and the curling portion, wherein a gasket is mounted on an upper portion of the curled edge portion of the cylindrical tank, The cover assembly is configured so that a safety device for current interruption and a safety vent for internal pressure drop are stacked below the upper end cover, and the current interruption device is formed at a lower end of the safety vent, The electrode assembly includes a positive electrode tab and a negative electrode tab led out from the electrode assembly, wherein the positive electrode tab is connected to the cap assembly, and the negative electrode tab is connected to a bottom surface spaced apart from the receiving portion of the cylindrical can, and The anti-corrosion layer is formed on a surface of the gasket facing the inner surface of the secondary battery, wherein the electrolyte solution comprises a non-aqueous electrolyte solution and a lithium salt, the lithium salt comprising a lithium imide-based salt, wherein the organic-inorganic hybrid layer comprises one or more inorganic particles, wherein the one or more inorganic particles are selected from the group consisting of: (a) inorganic particles having a dielectric constant of 1 or greater, (b) inorganic particles having piezoelectricity, (c) thermally conductive inorganic particles, and (d) inorganic particles having lithium ion transport capability, wherein the inorganic particles having a dielectric constant of 1 or greater include SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiC, or a mixture thereof, The thermally conductive inorganic particles include one or more selected from aluminum nitride, boron nitride, aluminum oxide, silicon carbide, and beryllium oxide.

2. The secondary battery according to claim 1, wherein: The metal is composed of any one selected from aluminum, nickel, stainless steel, copper, iron, bronze, and brass.

3. The secondary battery according to claim 1, wherein: The electrode assembly is a wound-type electrode assembly or a stacked / folded-type electrode assembly.

4. The secondary battery according to any one of claims 1 to 3, wherein: The secondary battery further includes a hollow center pin inserted into a central portion of the electrode assembly, and the anti-corrosion layer is also formed on an outer surface where the center pin and the electrolyte solution are in contact with each other.

5. The secondary battery according to claim 4, wherein: An anti-corrosion layer is also formed on the hollow inner surface of the center pin.

6. The secondary battery according to claim 4, wherein: The center pin is made of any one selected from aluminum, nickel, stainless steel, copper, iron, bronze and brass.

7. The secondary battery according to claim 1, wherein: The organic-inorganic hybrid layer further includes a binder polymer.

8. A prismatic secondary battery configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution, The battery housing is made of metal and includes a rectangular can body that is open at its upper end and houses the electrode assembly and the electrolyte solution together; and a top cover that includes a cover terminal that is coupled and sealed to the upper end of the rectangular can body and connected to the electrode terminal of the electrode assembly, and wherein the anti-corrosion layer of the organic-inorganic hybrid layer is formed on the inner surface of the rectangular can body where the battery case is in contact with the electrolyte solution, or on the inner surface of the rectangular can body and the inner surface of the top cover excluding the cover terminal, wherein the electrode assembly includes a positive electrode tab and a negative electrode tab extending therefrom, and the positive electrode tab and the negative electrode tab are respectively connected to the cover terminal, and the positive electrode tab, the negative electrode tab, and the cover terminal are formed with a conductive layer containing a conductive material that is capable of preventing corrosion and is also conductive, wherein the electrolyte solution comprises a non-aqueous electrolyte solution and a lithium salt, the lithium salt comprising a lithium imide-based salt, wherein the organic-inorganic hybrid layer comprises one or more inorganic particles, wherein the one or more inorganic particles are selected from the group consisting of: (a) inorganic particles having a dielectric constant of 1 or greater, (b) inorganic particles having piezoelectricity, (c) thermally conductive inorganic particles, and (d) inorganic particles having lithium ion transport capability, wherein the inorganic particles having a dielectric constant of 1 or greater include SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiC, or a mixture thereof, The thermally conductive inorganic particles include one or more selected from aluminum nitride, boron nitride, aluminum oxide, silicon carbide, and beryllium oxide.

9. The secondary battery according to claim 8, wherein: The metal is composed of any one selected from aluminum, nickel, stainless steel, copper, iron, bronze, and brass.

10. The secondary battery according to claim 8, wherein: The electrode assembly is a wound-type electrode assembly or a stacked / folded-type electrode assembly.

11. The secondary battery according to any one of claims 8 to 10, wherein: The secondary battery further includes a hollow center pin inserted into a central portion of the electrode assembly, and the anti-corrosion layer is also formed on an outer surface where the center pin and the electrolyte solution are in contact with each other.

12. The secondary battery according to claim 11, wherein: An anti-corrosion layer is also formed on the hollow inner surface of the center pin.

13. The secondary battery according to claim 11, wherein: The center pin is made of any one selected from aluminum, nickel, stainless steel, copper, iron, bronze and brass.

14. The secondary battery according to claim 8, wherein: The organic-inorganic hybrid layer further includes a binder polymer.

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