Secondary battery, battery pack, and secondary battery design system

Abstract

The present disclosure relates to a secondary battery, and the technical problem to be solved is to provide a secondary battery that prevents corrosion from occurring on a cap plate. To this end, the present disclosure provides a secondary battery comprising: an electrode assembly including a first electrode and a second electrode; a case for accommodating the electrode assembly; a cap plate covering an opening of the case and electrically connected to the second electrode; and a gasket for sealing the opening of the case while surrounding the cap plate along the outer peripheral surface of the cap plate.

Description

Secondary batteries, battery packs, and secondary battery design systems

[0001] The present disclosure relates to a secondary battery, a battery pack, and a secondary battery design system.

[0002]

[0003] In general, the demand for high-energy-density, high-capacity rechargeable batteries is rapidly increasing in line with the recent rapid proliferation of electronic devices using batteries, such as mobile phones, laptop computers, and electric vehicles. Accordingly, research and development to improve the performance of lithium-ion batteries is actively underway.

[0004] A lithium secondary battery is a battery comprising a positive electrode and a negative electrode containing an active material capable of lithium ion intercalation and deintercalation, and an electrolyte, and produces electrical energy through oxidation and reduction reactions when lithium ions are intercalated / deintercalated from the positive electrode and the negative electrode.

[0005] The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art.

[0006]

[0007] The present invention aims to provide a secondary battery in which internal corrosion is prevented, a battery pack including such a secondary battery, and a secondary battery design system for designing such a secondary battery.

[0008] For example, the present invention aims to provide a secondary battery that induces a cap plate to have polarity, a battery pack including such a secondary battery, and a secondary battery design system for designing such a secondary battery.

[0009] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems can be clearly understood by those skilled in the art from the description of the invention below.

[0010]

[0011] A secondary battery according to the present invention for solving the above technical problem may include: an electrode assembly comprising a first electrode and a second electrode; a case housing the electrode assembly; a cap plate covering the opening of the case and electrically connected to the second electrode; and a gasket that seals the opening of the case while wrapping the cap plate along the outer surface of the cap plate.

[0012] For example, the cap plate may include at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof.

[0013] For example, the secondary battery may include a second current collector plate located between an electrode assembly and a cap plate and connected to a second electrode; and the second current collector plate may include a main body portion connected to the second electrode; and a leg portion extending radially from the main body portion toward the inner surface of a case and electrically connecting the main body portion and the case.

[0014] For example, the second collector plate may further include a connecting part, one side of which is connected to the main body and the other side of which is in contact with the upper surface of the cap plate.

[0015] For example, the other side of the connection can extend between the gasket and the cap plate.

[0016] For example, the gasket seals the opening of the case by wrapping at least one of the upper surface and the side of the edge of the cap plate, and the leg portion may extend between the gasket and the case.

[0017] For example, the gasket seals the opening of the case by wrapping at least one of the side and bottom surfaces of the edge of the cap plate, and the leg portion may extend between the upper surface of the edge of the cap plate and the case.

[0018] For example, the gasket seals the opening of the case while wrapping at least one of the upper and lower surfaces of the edge of the cap plate, and the leg portion may extend between the gasket and the case.

[0019] For example, the cap plate may include a magnetic material.

[0020] For example, a gasket can electrically connect the case and the cap plate.

[0021] For example, the gasket may include a conductive polymer or conductive carbon.

[0022] For example, the gasket may include an insulating gasket comprising an insulating material; and a coating layer comprising a conductive material coated on at least a portion of the exterior of the insulating gasket.

[0023] For example, the secondary battery may further include a protective member comprising an insulating material, which is formed by covering an exposed portion of a gasket exposed to the outside from between a case and a cap plate when the conductive material includes a metal.

[0024] For example, the gasket may include an insulating gasket comprising an insulating material; and one or more conductive structures provided to penetrate the interior of the insulating gasket and connecting the case and the cap plate.

[0025] For example, the secondary battery includes a main body portion connected to a second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which is in contact with the upper surface of the cap plate; and further includes a second current collector plate located between the electrode assembly and the cap plate; and the gasket may include a conductive material.

[0026] For example, the secondary battery may include a main body portion connected to a second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which is in contact with the upper surface of the cap plate; and further include a second current collector plate located between the electrode assembly and the cap plate; and the gasket may include an insulating gasket comprising an insulating material; and a coating layer coated on at least a portion of the exterior of the insulating gasket and comprising a conductive material.

[0027] For example, the secondary battery may include a main body portion connected to a second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which is in contact with the upper surface of the cap plate; and further include a second current collector plate located between the electrode assembly and the cap plate; and the gasket may include an insulating gasket comprising an insulating material; and one or more conductive structures provided through the interior of the insulating gasket and connecting the case and the cap plate.

[0028] A battery pack according to the present invention for solving the above technical problem comprises: a plurality of secondary batteries; and a housing for housing the plurality of secondary batteries; and the secondary batteries may include: a cap plate that covers the opening of the case and is electrically connected to a second electrode; and a gasket that seals the opening of the case while wrapping the cap plate along the outer surface of the cap plate.

[0029] A secondary battery design system according to the present invention for solving the above technical problem is a secondary battery design system that designs a secondary battery comprising: an electrode assembly including a first electrode and a second electrode; a case housing the electrode assembly; and a cap plate covering an opening of the case; and includes a processor that determines the polarity of the cap plate according to the material group of the cap plate, wherein the processor can design the secondary battery such that if the material group is a first material group, the cap plate is insulated from the second electrode, and if the material group is a second material group, the cap plate is electrically connected to the second electrode.

[0030] For example, the second material group may include at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof.

[0031]

[0032] According to the present invention, a secondary battery in which internal corrosion is prevented, a battery pack including such secondary battery, and a secondary battery design system for designing such secondary battery can be provided.

[0033] According to the present invention, a secondary battery that solves the problem of rust occurring on a cap plate, a battery pack including such a secondary battery, and a secondary battery design system for designing such a secondary battery can be provided.

[0034] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0035]

[0036] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0037] FIG. 1 is a perspective view schematically showing the configuration of a battery module according to one embodiment of the present invention.

[0038] FIG. 2 is a plan view schematically showing the configuration of a battery module according to one embodiment of the present invention.

[0039] FIG. 3 is a perspective view schematically showing the configuration of a secondary battery according to one embodiment of the present invention.

[0040] FIG. 4 is a cross-sectional view schematically showing the configuration of a secondary battery according to one embodiment of the present invention.

[0041] FIG. 5 is an enlarged perspective view of a current collector plate according to one embodiment of the present invention.

[0042] FIG. 6 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0043] FIG. 7 is a cross-sectional view schematically showing the configuration of a secondary battery to which a current collector plate according to one embodiment of the present invention is applied.

[0044] FIG. 8 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0045] FIG. 9 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0046] FIG. 10 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0047] FIG. 11 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0048] FIG. 12 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0049] FIG. 13 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0050] FIG. 14 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0051] Figure 15 is a cross-sectional view showing an enlarged view of A in Figure 4.

[0052] FIG. 16 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0053] FIG. 17 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0054] FIG. 18 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0055] FIG. 19 is a block diagram illustrating the components of a secondary battery design system according to one embodiment of the present invention.

[0056]

[0057] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe their invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. It should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0058] Additionally, as used herein, “comprise, include” and / or “comprising, including” specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and / or groups.

[0059] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0060] The statement that two subjects of comparison are 'identical' means that they are 'substantially identical.' Therefore, substantial identity may include deviations considered low in the industry, for example, deviations within 5%. Additionally, the statement that a parameter is uniform in a given area may mean that it is uniform from an average perspective.

[0061] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0062] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0063] The fact that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0064] Furthermore, where one component is described as being "on," "connected to," or "coupled to" another component, it should be understood that while the components may be directly connected or coupled to each other, another component may be "interposed" between each component, or that each component may be "connected," "coupled," or "coupled" through another component.

[0065] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Additionally, the use of “may” when describing embodiments of the present disclosure relates to “one or more embodiments of the present disclosure.” Expressions such as “one or more” and “one or more” preceding a list of elements modify the entire list of elements and do not modify individual elements of the list.

[0066] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less, unless specifically stated otherwise.

[0067] When syntax such as "at least one of A, B, and C", "at least one of A, B, or C", "at least one selected from the group of A, B, and C", or "at least one selected from A, B, and C" is used to specify a list of elements A, B, and C, the syntax can refer to any suitable combination.

[0068] The term "use" may be considered synonymous with the term "utilize." As used herein, "substantially," "about," and similar terms are used as terms of approximation rather than degree, and are intended to account for the inherent variation of measured or calculated values ​​that a person skilled in the art would recognize.

[0069] In this specification, terms such as first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Accordingly, the first element, component, region, layer, or section discussed below may be named the second element, component, region, layer, or section without departing from the teachings of the exemplary embodiments.

[0070] Spatial relative terms such as "beneath," "below," "lower," "above," and "upper" may be used herein for ease of explanation to describe the relationship between one element or feature and another element(s) or feature(s) as illustrated in the drawings. Spatially relative positions are to be understood as encompassing different orientations of the device in use or operation, in addition to the orientations depicted in the figures. For example, if the device in the drawing is inverted, an element described as "below" or "below" is understood as "above" or "upper" of another element. Thus, the term "below" may encompass both the up and down directions.

[0071] The terms used in this specification are intended to describe embodiments of the present disclosure and are not intended to limit the present disclosure.

[0072]

[0073] FIG. 1 is a perspective view schematically showing the configuration of a battery pack according to one embodiment of the present invention.

[0074] FIG. 2 is a plan view schematically showing the configuration of a battery pack according to one embodiment of the present invention.

[0075] Referring to FIGS. 1 and 2, a battery pack (1000) according to various embodiments may include a housing (1100), a secondary battery (100), and a busbar (1200).

[0076] The housing (1100) forms the general outline of the battery pack and can provide a space in which the secondary battery (100) can be accommodated.

[0077] The housing (1100) according to the present embodiment may include a housing body (1110) and a cover (1120).

[0078] The housing body (1110) can be formed to have a box shape with an empty interior and one side open. The cross-sectional shape of the housing body (1110) is not limited to the square shape shown in FIG. 1, but can be designed to have various shapes such as polygons, circles, and ellipses.

[0079] The cover (1120) is coupled to the housing body (1110) and can close the internal space of the housing body (1110). For example, the cover (1120) may be formed to have a shape roughly like a plate and may be positioned to face the open side of the housing body (1110). The cover (1120) may be fixed to the housing body (1110) by various types of coupling methods, such as bolting, welding, or snap-fitting.

[0080] The secondary battery (100) can function as a unit structure that stores and supplies power in a battery pack.

[0081] Multiple secondary batteries (100) may be provided. Multiple secondary batteries (100) may be arranged inside the housing (1100) to form various patterns, such as a grid or a zigzag pattern. Multiple secondary batteries (100) may be arranged side by side. The number of secondary batteries (100) can be varied in design depending on the size, shape, etc. of the housing (1100). The detailed configuration of the secondary batteries will be described later.

[0082] A bus bar (1200) can electrically connect multiple secondary batteries (100). Multiple secondary batteries (100) can be connected in series or in parallel by the bus bar (1200). For example, the bus bar (1200) can connect secondary batteries (100) arranged in the same row inside the housing (1100) in parallel with each other, and connect secondary batteries (100) arranged in two adjacent rows in series with each other. The bus bar (1200) can be formed of an electrically conductive material such as copper, aluminum, or nickel.

[0083] Referring to FIG. 2, the busbar (1200) according to the present embodiment may include a main busbar (1210), a first branch busbar (1220), and a second branch busbar (1230).

[0084] The main busbar (1210) can be positioned between rows of adjacent secondary batteries (100). Multiple main busbars (1210) may be provided. The main busbar (1210) may extend in a straight line between rows of secondary batteries (100), or it may be regularly bent in a zigzag shape. Multiple main busbars (1210) may be positioned individually between different rows of adjacent secondary batteries (100). Multiple main busbars (1210) may be electrically interconnected.

[0085] The first branch bus bar (1220) can be extended from the main bus bar (1210) toward the rivet of the secondary battery (100) described later. The first branch bus bar (1220) can be mechanically and electrically connected to the rivet by laser welding, ultrasonic welding, etc.

[0086] The second branch bus bar (1230) can be extended from the main bus bar (1210) toward the case of the secondary battery (100) described later. The second branch bus bar (1230) can be mechanically and electrically connected to the case by laser welding, ultrasonic welding, etc.

[0087] Hereinafter, a secondary battery (100) according to one embodiment of the present invention will be described.

[0088]

[0089] FIG. 3 is a perspective view schematically showing the configuration of a secondary battery according to one embodiment of the present invention.

[0090] FIG. 4 is a cross-sectional view schematically showing the configuration of a secondary battery according to one embodiment of the present invention.

[0091] In FIGS. 3 and 4, 100 represents a secondary battery according to one embodiment of the present invention.

[0092] Referring to FIGS. 3 and 4, a secondary battery (100) according to the present embodiment (e.g., including the secondary battery (100) described in FIGS. 1 and 2) comprises an electrode assembly (10) and a case (20) housing the electrode assembly (10). Additionally, the secondary battery (100) further comprises a rivet (30) that is inserted into a hole (20h) formed on one side of the case (20) and electrically connected to the electrode assembly (10), and a cap plate (60) that covers an opening formed on the other side of the case (20). However, the components of the secondary battery (100) are not limited to the components shown in FIG. 1, and the secondary battery (100) may include only some of the components shown in FIGS. 3 and 4 and / or include additional components other than those shown in FIGS. 3 and 4.

[0093] In the following description, the secondary battery (100) is described as a cylindrical battery as a lithium-ion secondary battery. However, the present invention is not limited thereto, and the secondary battery may be a lithium polymer battery or a prismatic battery.

[0094]

[0095] The electrode assembly (10) can function as a unit structure that performs charging and discharging operations of power in a secondary battery (100).

[0096] The electrode assembly (10) includes a first electrode and a second electrode. The first electrode is a positive or negative electrode. The second electrode is a negative or positive electrode and has a polarity different from that of the first electrode.

[0097] Additionally, the electrode assembly (10) may further include a separator between the first electrode and the second electrode. The electrode assembly (10) can prevent the first electrode and the second electrode from coming into contact with each other and prevent a short circuit from occurring between the first electrode and the second electrode. Accordingly, the electrode assembly (10) may be formed by stacking the first electrode, the second electrode, and the separator provided between the first electrode and the second electrode.

[0098] At this time, when the electrode assembly (10) forms a cylindrical shape, the laminated structure including the first electrode, the second electrode, and the separator can be wound to form a jelly roll. For example, the electrode assembly (10) may have a shape wound along a clockwise or counterclockwise direction around a winding axis. The cross-sectional shape of the electrode assembly (10) can be designed to be various shapes, such as elliptical or polygonal, in addition to a circular shape. Here, the winding axis may refer to a straight line penetrating the center of the electrode assembly (10).

[0099] A detailed description of each component of the electrode assembly (10) is as follows.

[0100]

[0101] positive electrode active material

[0102] As a positive electrode active material, a compound capable of reversible intercalation and deintercalation of lithium (a lithated intercalation compound) may be used. Specifically, one or more composite oxides of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof may be used.

[0103] The above composite oxide may be a lithium transition metal composite oxide, and specific examples include a lithium nickel-based oxide, a lithium cobalt-based oxide, a lithium manganese-based oxide, a lithium iron phosphate-based compound, a cobalt-free nickel-manganese-based oxide, or a combination thereof.

[0104] As an example, compounds represented by any one of the following chemical formulas may be used. LiaA1-bXbO2-cDc(0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); LiaMn2-bXbO4-cDc(0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); LiaNi1-b-cCobXcO2-αDα(0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); LiaNi1-b-cMnbXcO2-αDα(0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); LiaNibCocL1dGeO2(0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); LiaNiGbO2(0.90≤a≤1.8, 0.001≤b≤0.1); LiaCoGbO2(0.90≤a≤1.8, 0.001≤b≤0.1); LiaMn1-bGbO2 (0.90≤a≤1.8, 0.001≤b≤0.1); LiaMn2GbO4 (0.90≤a≤1.8, 0.001≤b≤0.1); LiaMn1-gGgPO4(0.90≤a≤1.8, 0≤g≤0.5); Li(3-f)Fe2(PO4)3(0≤f≤2); LiaFePO4(0.90≤a≤1.8).

[0105] In the above chemical formula, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L1 is Mn, Al, or a combination thereof.

[0106] For example, the above-mentioned positive electrode active material may be a high-nickel positive electrode active material in which the nickel content relative to 100 mol% of the metal excluding lithium in the lithium transition metal composite oxide is 80 mol% or more, 85 mol% or more, 90 mol% or more, 91 mol% or more, or 94 mol% or more and 99 mol% or less. The high-nickel positive electrode active material can achieve high capacity and can be applied to high-capacity, high-density lithium batteries.

[0107] anode

[0108] A positive electrode for a secondary battery (100) may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may include a positive electrode active material and may further include a binder and / or a conductive material.

[0109] For example, the above anode may further include an additive that can serve as a sacrificial anode.

[0110] The content of the above positive active material is 90% to 99.5% by weight with respect to 100% by weight of the positive active material layer, and the content of the above binder and conductive material may each be 0.5% to 5% by weight with respect to 100% by weight of the positive active material layer.

[0111] The above binder serves to adhere the positive active material particles well to each other and also to adhere the positive active material well to the current collector. Representative examples of binders include, but are not limited to, polyvinyl alcohol, carboxymethylcellulose, hydroxypropylcellulose, diacetylcellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers containing ethylene oxide, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, epoxy resin, (meth)acrylic resin, polyester resin, nylon, etc.

[0112] The above conductive material is used to impart conductivity to the electrode, and any electronically conductive material that does not cause chemical changes can be used in the battery being constructed. Examples of conductive materials include carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanofiber, carbon nanotube; metal-based materials in the form of metal powder or metal fibers containing copper, nickel, aluminum, silver, etc.; conductive polymers such as polyphenylene derivatives; or mixtures thereof.

[0113] Al may be used as the current collector mentioned above, but is not limited thereto.

[0114] cathode active material

[0115] The negative electrode active material includes a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0116] A material capable of reversibly intercalating / deintercalating the above lithium ions may be a carbon-based negative electrode active material, such as crystalline carbon, amorphous carbon, or a combination thereof. Examples of the crystalline carbon include graphite such as amorphous, plate-like, flake-like, spherical, or fibrous natural graphite or artificial graphite, and examples of the amorphous carbon include soft carbon or hard carbon, mesophase pitch carbide, calcined coke, etc.

[0117] As the above lithium metal alloy, an alloy of lithium and a metal selected from Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al, and Sn may be used.

[0118] As a material capable of doping and undoping the above lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material may be used. The Si-based negative electrode active material may be silicon, a silicon-carbon composite, SiOx (0 < x < 2), a Si-Q alloy (wherein Q is selected from alkali metals, alkaline earth metals, group 13 elements, group 14 elements (excluding Si), group 15 elements, group 16 elements, transition metals, rare earth elements, and combinations thereof), or a combination thereof. The Sn-based negative electrode active material may be Sn, SnO2, a Sn-based alloy, or a combination thereof.

[0119] The silicon-carbon composite may be a composite of silicon and amorphous carbon. According to one embodiment, the silicon-carbon composite may be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles. For example, it may include a secondary particle (core) assembled from silicon primary particles and an amorphous carbon coating layer (shell) located on the surface of the secondary particle. The amorphous carbon may also be located between the silicon primary particles, so that, for example, the silicon primary particles may be coated with amorphous carbon. The secondary particles may be dispersed in an amorphous carbon matrix.

[0120] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core comprising crystalline carbon and silicon particles and an amorphous carbon coating layer located on the surface of the core.

[0121] The above Si-based or Sn-based negative electrode active material can be used in combination with a carbon-based negative electrode active material.

[0122] cathode

[0123] A negative electrode for a secondary battery (100) comprises a current collector and a negative electrode active material layer located on the current collector. The negative electrode active material layer comprises a negative electrode active material and may further comprise a binder and / or a conductive material.

[0124] For example, the negative electrode active material layer may comprise 90% to 99% by weight of negative electrode active material, 0.5% to 5% by weight of binder, and 0% to 5% by weight of conductive material.

[0125] The above binder serves to effectively bond the negative electrode active material particles to each other and also to effectively bond the negative electrode active material to the current collector. As the binder, a non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof may be used.

[0126] Examples of the above-mentioned non-aqueous binders include polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide imide, polyimide, or combinations thereof.

[0127] The above-mentioned water-based binder may be selected from styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluororubber, polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphazene, poly(meth)acrylonitrile, ethylenepropylenediene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0128] When a water-based binder is used as the above-mentioned cathode binder, a cellulose-based compound capable of imparting viscosity may be further included. As this cellulose-based compound, one or more types such as carboxymethyl cellulose, hydroxypropylmethyl cellulose, methyl cellulose, or alkali metal salts thereof may be mixed and used. Na, K, or Li may be used as the alkali metal.

[0129] The above dry binder is a polymer material capable of fiberization, and may be, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, or a combination thereof.

[0130] The above conductive material is used to impart conductivity to the electrode, and any electronically conductive material that does not cause chemical changes can be used in the battery being constructed. Specific examples include carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjenblack, carbon fiber, carbon nanofiber, carbon nanotube; metal-based materials in the form of metal powder or metal fibers including copper, nickel, aluminum, silver, etc.; conductive polymers such as polyphenylene derivatives; or mixtures thereof.

[0131] As the above-mentioned cathode current collector, a material selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and combinations thereof may be used.

[0132] Separator

[0133] Depending on the type of secondary battery (100), a separator may be present between the positive electrode (10) and the negative electrode (20). As such a separator, polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof may be used, and of course, a mixed multilayer film such as a polyethylene / polypropylene two-layer separator, a polyethylene / polypropylene / polyethylene three-layer separator, or a polypropylene / polyethylene / polypropylene three-layer separator may be used.

[0134] The above separation membrane may include a porous substrate and a coating layer comprising an organic material, an inorganic material, or a combination thereof located on one or both sides of the porous substrate.

[0135] The porous substrate may be a polymer membrane formed from any one of the following: polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyacetal; polyamide; polyimide; polycarbonate; polyetherketone; polyaryletherketone; polyetherimide; polyamideimide; polybenzimidazole; polyethersulfone; polyphenylene oxide; cyclic olefin copolymer; polyphenylene sulfide; polyethylene naphthalate; glass fiber; Teflon; and polytetrafluoroethylene, or a copolymer or mixture of two or more of these.

[0136] The above organic material may include a polyvinylidene fluoride-based polymer or a (meth)acrylic-based polymer.

[0137] The above inorganic material may include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but is not limited thereto.

[0138] The above organic and inorganic materials may exist mixed in a single coating layer, or may exist in a stacked form with a coating layer containing organic materials and a coating layer containing inorganic materials.

[0139] The case (20) accommodates the electrode assembly (10). The case (20) seals the accommodated electrode assembly (10) together with the electrolyte.

[0140] electrolyte

[0141] The electrolyte for the secondary battery (100) includes a non-aqueous organic solvent and a lithium salt.

[0142] The above-mentioned non-aqueous organic solvent serves as a medium through which ions involved in the electrochemical reaction of the battery can move.

[0143] The above-mentioned non-aqueous organic solvent may be a carbonate-based, ester-based, ether-based, ketone-based, or alcohol-based solvent, an aprotic solvent, or a combination thereof.

[0144] The above carbonate-based solvents may include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methyl ethyl carbonate (MEC), ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), etc.

[0145] Ester-based solvents such as methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methylpropionate, ethylpropionate, decanolide, mevalonolactone, valerolactone, and caprolactone may be used.

[0146] As ether-based solvents, dibutyl ether, tetraglame, diglame, dimethoxyethane, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, tetrahydrofuran, etc. may be used. Additionally, as ketone-based solvents, cyclohexanone, etc. may be used. As alcohol-based solvents, ethyl alcohol, isopropyl alcohol, etc. may be used, and as aprotic solvents, nitriles such as R-CN (where R is a straight-chain, branched, or cyclic hydrocarbon group having 2 to 20 carbon atoms and may include a double bond, an aromatic ring, or an ether group); amides such as dimethylformamide; dioxolanes such as 1,3-dioxolane, 1,4-dioxolane; sulfolanes, etc. may be used.

[0147] The above-mentioned non-aqueous organic solvent can be used alone or in a mixture of two or more types.

[0148] In addition, when using a carbonate-based solvent, a mixture of cyclic carbonates and chain carbonates can be used, and the cyclic carbonates and chain carbonates can be mixed in a volume ratio of 1:1 to 1:9.

[0149] The above lithium salt is a material that is dissolved in an organic solvent and acts as a source of lithium ions within the battery, enabling the operation of a basic lithium battery and facilitating the movement of lithium ions between the positive and negative electrodes. Representative examples of lithium salts may include one or more selected from LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiAlO2, LiAlCl4, LiPO2F2, LiCl, LiI, LiN(SO3C2F5)2, Li(FSO2)2N (lithium bis(fluorosulfonyl)imide (LiFSI), LiC4F9SO3, LiN(CxF2x+1SO2)(CyF2y+1SO2)(x and y are integers from 1 to 20), lithium trifluoromethanesulfonate, lithium tetrafluoroethanesulfonate, lithium difluorobis(oxalate)phosphate (LiDFOB), and lithium bis(oxalate)borate (LiBOB).

[0150]

[0151] As described above, the case (20) is sealed after housing the electrode assembly (10) and the electrolyte. For example, the case (20) can be sealed by a cap plate (60).

[0152] Specifically, the case (20) forms the general appearance of the secondary battery (100). The case (20) includes an upper surface forming a cylindrical upper section and a side surface connected to the outer surface of the upper surface and extending vertically from the upper surface to form a side surface.

[0153] A hole (20h) may be formed on the upper surface of the case (20). The hole (20h) is formed by penetrating the upper surface of the case (20). The hole (20h) may be located at the center of the upper surface of the case (20). The hole (20h) may be formed, for example, at a position perpendicular to the winding core of the electrode assembly (10) and the ground. The shape of the hole (20h) may correspond to the shape of the rivet (30). For example, if the cross-section of the rivet (30) is circular, the cross-section of the hole (20h) may be formed in a circular shape. In this case, the diameter of the cross-section of the hole (20h) is larger than the diameter of the cross-section of the rivet (30).

[0154] At this time, the case (20) may have an open cylindrical lower section. The case (20) can seal the interior by closing the opening with a cap plate (60). Accordingly, the case (20) can prevent the electrolyte from leaking out and protect the electrode assembly (10).

[0155] Meanwhile, the case (20) can be manufactured from, for example, steel, stainless steel, aluminum, aluminum alloy, a combination thereof, or an equivalent thereof.

[0156] The cap plate (60) covers the opening of the case (20) and seals the case (20).

[0157] At this time, the secondary battery (100) may further include a gasket (80) to ensure that the case (20) is more securely sealed. The gasket (80) is formed, for example, in a ring shape. The gasket (80) may be positioned between the cap plate (60) and the inner surface of the case (20) while wrapping around the outer surface of the cap plate (60). Through this, the gasket (80) can prevent the electrolyte inside the secondary battery (100) from leaking out or causing safety issues.

[0158] At this time, the case (20) may form a beading portion (21) to fix the position of the cap plate (60) relative to the opening of the case (20). For example, the beading portion (21) is formed on the lower side of the case (20). The beading portion (21) is formed by the case (20) being concave from the outside to the inside. The beading portion (21) prevents the cap plate (60) from moving further into the case (20) from the opening of the case (20) through this concave portion. At this time, the case (20) may further form a crimping portion (22) to fix the position of the cap plate (60) relative to the opening of the case (20). The crimping portion (22) may be formed by the end of the opening of the case (20) being rolled toward the inside of the case (20). For example, the crimping portion (22) can be formed by bending toward the case (20) after the cap plate (60) is provided in the opening of the case (20). In this way, the cap plate (60) can cover the opening of the case (20).

[0159] At this time, the cap plate (60) can simultaneously perform the role of a vent. For example, the cap plate (60) may include a groove (61). The groove (61) may be damaged if the pressure inside the case (20) increases or the temperature rises. As the groove (61) is damaged, it can release gas generated inside the case (20) to the outside.

[0160] Meanwhile, the case (20) is electrically connected to the electrode assembly (10) housed inside the case (20). For example, the case (20) is electrically connected to the second electrode. The second electrode may be, for example, a negative electrode.

[0161] The secondary battery (100) may further include a second current collector plate (70) located at the bottom of the electrode assembly (10) to electrically connect the case (20) and the second electrode. For example, the second current collector plate (70) may be located between the bottom of the electrode assembly (10) and the top of the cap plate (60). At this time, the second current collector plate (70) and the cap plate (60) may be insulated from each other by a gasket (80). The second current collector plate (70) is, for example, a negative current collector plate. The second current collector plate (70) is connected to the second electrode. For example, the second current collector plate (70) is connected to the tab of the second electrode. In addition, the second current collector plate (70) is connected to the case (20). Through this, the case (20) is electrically connected to the second electrode and may have the same polarity as the second electrode. That is, for example, the case (20) can have negative polarity.

[0162] A rivet (30) is inserted into a hole (20h) formed on the upper surface of a case (20). The rivet (30) is inserted into the hole (20h) and electrically connected to an electrode assembly (10) housed inside the case (20). For example, the rivet (30) is electrically connected to a first electrode. The first electrode may be, for example, a positive electrode.

[0163] The secondary battery (100) may further include a first current collector plate (40) located on the upper part of the electrode assembly (10) to electrically connect the rivet (30) and the first electrode. The first current collector plate (40) is, for example, a positive current collector plate. The first current collector plate (40) is connected to the first electrode. For example, the first current collector plate (40) is connected to the tab of the first electrode. In addition, the first current collector plate (40) is connected to the rivet (30). Through this, the rivet (30) is electrically connected to the first electrode and can have the same polarity as the first electrode. That is, for example, the rivet (30) can have positive polarity.

[0164] At this time, the rivet (30) may include a conductive material to be electrically connected to the first electrode. For example, the rivet (30) includes a metal. For example, the rivet (30) includes aluminum (Al).

[0165] Meanwhile, the secondary battery (100) may further include an insulating layer (90). The insulating layer (90) may be provided on the first current collector plate (40). The insulating layer (90) prevents the first current collector plate (40) and the case (20) from being electrically connected.

[0166] Through such a configuration, a secondary battery (100) according to one embodiment of the present invention can provide a battery with improved capacity by eliminating the upper beading portion. In addition, the secondary battery (100) can solve safety or financial problems that occur when the secondary battery (100) explodes upward by positioning the cap plate (60) at the bottom.

[0167] The cap plate (60) may include a second material group. The second material group may include, for example, at least one material selected from the group consisting of iron (Fe), SUS, nickel (Ni), zinc (Sn), lead (Pb), copper (Cu), silver (Ag), platinum (Pt), gold (Au), and combinations of at least two of these.

[0168] Through this, the cap plate (60) can improve the strength and / or safety of the secondary battery (100). For example, the cap plate (60) can further improve the ability to protect the secondary battery (100) from external impacts.

[0169] Additionally, the cap plate (60) improves the transport efficiency of the secondary battery (100). For example, when transport of the secondary battery (100) is required, the secondary battery (100) can be transported by magnetic force by connecting a magnet to the cap plate (60). Furthermore, for example, when transport of a battery module (1000) containing multiple secondary batteries (100) is required, the battery module (1000) can be transported by magnetic force by connecting magnets to multiple cap plates (60).

[0170] However, if the cap plate (60) includes a second material group, the cap plate (60) may undergo galvanic corrosion due to long-term exposure to the electrolyte. To solve this problem, the secondary battery (100) according to one embodiment of the present invention may have the cap plate (60) have polarity. For example, the cap plate (60) may be electrically connected to the case (20). As described above, the case (20) is electrically connected to the second electrode. Accordingly, the cap plate (60) may be electrically connected to the second electrode.

[0171] Hereinafter, various embodiments are described in which the cap plate (60) has polarity.

[0172]

[0173] FIG. 5 is an enlarged perspective view of a current collector plate according to one embodiment of the present invention.

[0174] FIG. 6 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0175] FIG. 7 is a cross-sectional view schematically showing the configuration of a secondary battery to which a current collector plate according to one embodiment of the present invention is applied.

[0176] In FIGS. 5 to 7, 100 represents a secondary battery according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 4).

[0177] The secondary battery (100) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly; and a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode. The secondary battery (100) comprises: a rivet (30) inserted into a hole (20h) of the case (20) and electrically connected to the first electrode; a first current collector plate (40) located between the electrode assembly (10) and the rivet (30) and connecting the first electrode and the rivet (30); and a second current collector plate (70) located between the electrode assembly (10) and the cap plate (60) and connected to the second electrode.

[0178] As illustrated in FIG. 5, the second collector plate (70) includes a main body portion (71) connected to the second electrode; and a leg portion (72) extending radially from the main body portion (71) toward the inner surface of the case (20) to electrically connect the main body portion (71) and the case (20).

[0179] The second collector plate (70) includes a main body part (71) and a leg part (72).

[0180] The main body (71) is connected to the second electrode. For example, the main body (71) is connected to the tab (11) of the second electrode included in the second electrode. At this time, the tab (11) of the second electrode includes, for example, a tab attached to the electrode plate of the second electrode and extending to the outside of the electrode plate. Or, the tab (11) of the second electrode includes, for example, a non-stick portion corresponding to the substrate of the second electrode. By contacting the tab (11) of the second electrode, the main body (71) is electrically connected to the second electrode. Through this, the main body (71) can have the same polarity as the second electrode.

[0181] To this end, the main body (71) is formed, for example, in the shape of a flat plate. By being formed in the shape of a plate, the main body (71) can be uniformly connected to the tabs (11) of the second electrode. However, the shape of the main body (71) is not limited to this, and the main body (71) can have any shape that is advantageous for contacting the tabs (11) of the second electrode.

[0182] The leg portion (72) electrically connects the main body portion (71) and the case (20). To this end, one side of the leg portion (72) is connected to the main body portion (71). Additionally, the other side of the leg portion (72) is connected to the case (20). That is, the leg portion (72) is formed by extending from the main body portion (71) toward the case (20). At this time, the leg portion (72) may be formed by extending in a straight direction from the main body portion (71) toward a part of the inner surface of the case (20), or it may be formed by extending after undergoing one or more bends.

[0183] For example, as illustrated in FIG. 5, the gasket (80) wraps around the outer surface of the cap plate (60). The cap plate (60) is provided in the space between the beading portion (21) and the crimping portion (22) and is fixed to the case (20). At this time, the gasket (80) is positioned in the space between the cap plate (60) and the case (20), causing the cap plate (60) to seal the case (20). Thus, the inner surface of the case (20) between the beading portion (21) and the crimping portion (22) can come into contact with the gasket (80).

[0184] At this time, the leg portion (72) can be extended toward the inner surface of the case (20) and the gasket (80). Through this, the leg portion (72) can come into contact with the case (20) without coming into contact with the cap plate (60).

[0185] Through this, the leg portion (72) electrically connects the case (20) and the main body portion (71) so that the case (20) has the same polarity as the main body portion (71). For example, the case (20) can have the same polarity as the second electrode.

[0186] The cap plate (60) includes a metal material to ensure rigidity. The metal material may include a first material group and a second material group.

[0187] For example, the cap plate (60) comprises at least one material selected from a first group of materials. The first group of materials comprises at least one selected from a group consisting of, for example, aluminum (Al), SUS, and combinations thereof.

[0188] When the cap plate (60) includes a first material group, the cap plate (60) is insulated from the case (20) and / or the second current collector plate (70). For example, the cap plate (60) may not come into contact with the case (20) by having its outer surface surrounded by a gasket (80). Additionally, the cap plate (60) may prevent the leg portion (72) from coming into contact with the cap plate (60) by having its outer surface surrounded by a gasket (80). Through this, the cap plate (60) is insulated from the second electrode. For example, the cap plate (60) may not have polarity.

[0189] In this way, the secondary battery (100) can prevent the cap plate (60) from corroding by ensuring that the cap plate (60) does not have polarity when the cap plate (60) includes the first material group.

[0190] Alternatively, for example, the cap plate (60) comprises at least one material selected from a second group of materials. The second group of materials comprises, for example, at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof.

[0191] In this way, when the cap plate (60) includes a second material group, the cap plate (60) is electrically connected to the case (20) and / or the second current collector plate (70). For example, at least a portion of the cap plate (60) may come into contact with the case (20). To this end, a gasket (80) may be formed to surround the cap plate (60), excluding the area where the cap plate (60) and the case (20) come into contact.

[0192] Alternatively, for this purpose, the second collector plate (70) may further include a connecting means electrically connected to the cap plate (60). The connecting means includes, for example, a connecting part (73).

[0193] For example, as illustrated in FIG. 5, the second collector plate (70) further includes a connecting part (73) that extends from the main body (71) toward the cap plate (60) and connects the main body (71) and the cap plate (60).

[0194] For example, one side (73a) of the connecting part (73) is connected to the main body part (71), and the other side (73b) contacts the upper surface of the cap plate (60). One side (73a) of the connecting part is formed on one surface of the main body part (71). At this time, one surface of the main body part (71) may be the same as the surface where the leg part (72) is formed from the main body part (71). For example, one surface of the main body part (71) includes the lower surface of the main body part (71).

[0195] For example, the second collector plate (70) includes a leg portion (72) that spreads radially from the bottom side toward the lower side and a connecting portion (73) that extends from the bottom side toward the lower side.

[0196] One side (73a) of the connecting portion extends from the main body portion (71) toward the cap plate (60). The other side (73b) of the connecting portion may be formed by being bent in a direction different from the direction in which the one side (73a) of the connecting portion extends, in order to more easily come into contact with the cap plate (60). Through this, the other side (73b) of the connecting portion can come into contact with the cap plate (60). For example, the other side (73b) of the connecting portion may come into contact with the upper surface of the cap plate (60) by welding or simply by contact.

[0197] However, the shape of the connecting part (73) is not limited to a branch shape as shown in FIGS. 5 to 7. For example, the connecting part (73) may be formed in a spring shape to connect the main body part (71) and the cap plate (60). Alternatively, for example, the connecting part (73) may be formed in a cylindrical shape or a hollow shape with the center of the cylinder empty to connect the main body part (71) and the cap plate (60).

[0198] Through this structure, the connecting part (73) can have the same polarity as the cap plate (60) and the main body part (71). For example, the second current collector plate (70) can have the same polarity as the cap plate (60) and the second electrode. For example, the second current collector plate (70) can have the same polarity as the cap plate (60) and the case (20).

[0199] In this way, the secondary battery (100) can prevent the cap plate (60) from corroding by making the cap plate (60) have polarity when it includes a second material group.

[0200] At this time, if the cap plate (60) includes SUS, the cap plate (60) may not have polarity, or the cap plate (60) may have a second electrode.

[0201] Meanwhile, for example, the cap plate (60) may include a magnetic material. For example, the cap plate (60) may include a material that is both a magnetic material and a metal. In this case, the magnetic material includes a material having a relative permeability of 1 or more. Alternatively, the magnetic material includes a ferromagnetic material. For example, the ferromagnetic material includes Fe, steel, etc.

[0202] In this way, the cap plate (60) includes a material that is both magnetic and metallic, thereby improving the transport efficiency of the secondary battery (100). For example, the secondary battery (100) can be transported using magnetic force, thereby making it easier to manufacture and / or transport the secondary battery (100).

[0203] Furthermore, as illustrated in FIGS. 1 and 2, a battery pack (1000) according to one embodiment of the present invention may include a plurality of such secondary batteries (100). A magnetic material may be disposed on at least one surface of the battery pack (1000) by means of a cap plate (60) included in the secondary battery (100). Accordingly, the battery pack (1000) may provide a method that facilitates manufacturing and / or transportation using magnetic force.

[0204] In this way, a secondary battery (100) according to one embodiment of the present invention can be designed differently in which the cap plate (60) is connected to the second electrode based on the material included in the cap plate (60). Through this, the secondary battery (100) provides a method to prevent internal corrosion. For example, the secondary battery (100) can provide a method to prevent the cap plate (60) from corroding.

[0205] Below, examples of various structures that allow the cap plate (60) to have the same polarity as the second electrode are described.

[0206]

[0207] FIG. 8 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0208] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 7) further comprises a gasket (80) that seals the opening of a case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60). At this time, the other side of the connecting portion (73) extends between the gasket (80) and the cap plate (60).

[0209] Figure 8 describes another form of the connecting part (73).

[0210] As described in FIGS. 5 to 7, the connecting portion (73) includes one side (73a) connected to the main body portion (71) and another side (73b) connected to the cap plate (60). The other side (73b) of the connecting portion contacts the upper surface of the cap plate (60).

[0211] At this time, the upper surface of the cap plate (60) may be an area where a gasket (80) surrounding the cap plate (60) is provided along the edge of the cap plate (60). That is, the connecting portion (73) may extend from the main body portion (71) toward the space between the cap plate (60) and the gasket (80). Accordingly, the other side (73a) of the connecting portion may be inserted and fixed between the gasket (80) and the upper surface of the cap plate (60).

[0212] Through this structure, the second collector plate (70) can be fixedly connected to the cap plate (60) without undergoing a separate welding or joining process to the cap plate (60).

[0213] At this time, as described in FIGS. 5 to 7, the second current collector plate (70) electrically connects the main body (71) and the case (70) through the leg portion (72). In addition, the second current collector plate (70) electrically connects the main body (71) and the cap plate (60) through the connection portion (73). Through this, the second current collector plate (70) can make the cap plate (60) have the same polarity as the second electrode. In addition, the second current collector plate (70) can make the cap plate (60) have the same polarity as the case (20).

[0214] FIGS. 5 to 8 describe the feature in which the second current collector plate (70) is connected to the cap plate (60) through the connecting part (73). Below, various examples in which the second current collector plate (70) can be connected to the cap plate (60) without including a separate connecting part (73) will be described.

[0215]

[0216] FIG. 9 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0217] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 8) further comprises a gasket (80) that seals the opening of a case (20) while wrapping at least one of the upper surface and side surface of the edge of a cap plate (60); and a leg portion (72) extends between the gasket (80) and the case (20).

[0218] The case (20) further includes a crimping portion (22) formed by rolling toward the lower surface so that the end of the opening contacts the lower surface of the edge of the cap plate (60).

[0219] As illustrated in FIG. 9, the gasket (80) can wrap around the cap plate (60) along the edge of the cap plate (60). In this case, the gasket (80) may be formed by wrapping only a portion of the upper surface (60u), side surface (60s), and lower surface (60b) on the edge side of the cap plate (60) that form the edge of the cap plate (60).

[0220] For example, the gasket (80) may be formed without covering the lower surface (60b) of the cap plate (60). For example, the gasket (80) may be formed by covering only the upper surface (60u) and / or side surface (60s) of the edge of the cap plate (60). In this way, the gasket (80) can completely seal the interior of the case (20) while securing the cap plate (60) to the case (20).

[0221] A portion of the lower surface (60b) of the cap plate (60) may come into contact with the case (20). For example, the lower surface (60b) of the edge of the cap plate (60) may come into contact with the crimping portion (22) that is rolled from the case (20) toward the cap plate (60).

[0222] In this way, the cap plate (60) can have the same polarity as the case (20) by being connected to the case (20). For example, the case (20) is electrically connected to the second current collector plate (70) through the leg portion (72). The case (20) is connected to the second electrode through the second current collector plate (70). At this time, the cap plate (60) can be connected to the second electrode by being connected to the case (20). Accordingly, the cap plate (60) can have the same polarity as the second electrode.

[0223]

[0224] FIG. 10 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0225] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 9) further comprises a gasket (80) that seals the opening of a case (20) while wrapping at least one of the side and bottom surfaces of the edge of a cap plate (60); and a leg portion (72) extends between the upper surface of the edge of the cap plate (60) and the case (20).

[0226] As illustrated in FIG. 10, the gasket (80) can wrap around the cap plate (60) along the edge of the cap plate (60). In this case, the gasket (80) may be formed by wrapping only a portion of the upper surface (60u), side surface (60s), and lower surface (60b) on the edge side of the cap plate (60) that form the edge of the cap plate (60).

[0227] For example, the gasket (80) may be formed without covering the upper surface (60u) of the cap plate (60). For example, the gasket (80) may be formed by covering only the side (60s) and / or lower surface (60b) of the edge of the cap plate (60). In this way, the gasket (80) can completely seal the interior of the case (20) while securing the cap plate (60) to the case (20).

[0228] Accordingly, the upper surface (60u) of the edge of the gasket (80) may be exposed without being covered by the gasket (80). Additionally, the upper surface (60u) of the edge of the second collector plate (70) may be formed facing the inner surface of the case (20). For example, the upper surface (60u) of the edge of the second collector plate (70) may be formed facing the inner surface of the beading portion (21). Accordingly, the inner surface of the beading portion (21) may be positioned on the upper surface (60u) of the edge of the second collector plate (70).

[0229] The leg portion (72) extends toward the inner surface of the beading portion (21) and the upper surface (60u) of the edge of the second collector plate (70). Accordingly, the leg portion (72) is fixed between the inner surface of the beading portion (21) and the upper surface (60u) of the edge of the second collector plate (70), so that it can come into contact with the case (20) and the second collector plate (70) simultaneously.

[0230] The case (20) is electrically connected to the second current collector plate (70) through the leg portion (72). That is, the case (20) is connected to the second electrode through the second current collector plate (70). At this time, the cap plate (60) is connected to the second current collector plate (70) through the leg portion (72). That is, the leg portion (72) is connected to the case (20) and the cap plate (60) simultaneously, so that the case (20) and the cap plate (60) can be connected to the second electrode. Accordingly, the cap plate (60) can have the same polarity as the case (20). Accordingly, the cap plate (60) can have the same polarity as the second electrode.

[0231]

[0232] FIG. 11 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0233] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 10) further comprises a gasket (80) that seals the opening of a case (20) while wrapping at least one of the upper and lower surfaces of the edge of a cap plate (60); and a leg portion (72) extends between the gasket (80) and the case (20).

[0234] As illustrated in FIG. 11, the gasket (80) can wrap around the cap plate (60) along the edge of the cap plate (60). In this case, the gasket (80) may be formed by wrapping only a portion of the upper surface (60u), side surface (60s), and lower surface (60b) on the edge side of the cap plate (60) that form the edge of the cap plate (60).

[0235] For example, the gasket (80) may be formed without covering the side (60s) of the cap plate (60). For example, the gasket (80) may be formed by covering only the upper surface (60u) and / or lower surface (60b) of the edge of the cap plate (60). This allows the gasket (80) to completely seal the interior of the case (20) while securing the cap plate (60) to the case (20).

[0236] The cap plate (60) can come into contact with the case (20) through the side (60s) of the edge corresponding to the outer surface. In this way, the cap plate (60) can have the same polarity as the case (20) by being connected to the case (20). For example, the case (20) is electrically connected to the second current collector plate (70) through the leg portion (72). The case (20) is connected to the second electrode through the second current collector plate (70). At this time, the cap plate (60) can be connected to the second electrode by being connected to the case (20). Accordingly, the cap plate (60) can have the same polarity as the second electrode.

[0237]

[0238] Meanwhile, the secondary battery (100) according to one embodiment of the present invention is not limited to the structures described in FIGS. 5 to 11. For example, the secondary battery (100) may be formed by a combination of the structures described in FIGS. 5 to 11. For example, the secondary battery (100) may be formed by a combination of the structures described in FIGS. 5 to 8 and the structures described in FIGS. 9 to 11.

[0239] Thus, a secondary battery (100) according to one embodiment of the present invention provides various embodiments in which, when the cap plate (60) includes a second material group, the cap plate (60) has the same polarity as the case (20). Through this, the secondary battery (100) can prevent internal corrosion.

[0240]

[0241] FIG. 12 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0242] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 11) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0243] For example, the gasket (80) can electrically connect the case (20) and the cap plate (60). By connecting the case (20) and the cap plate (60) connected to the second electrode, the gasket (80) can cause the cap plate (60) to have the same polarity as the second electrode. Through this, the secondary battery (100) can prevent corrosion of the cap plate (60).

[0244] For example, to electrically connect the case (20) and the cap plate (60), the gasket (80) comprises a conductive material. The conductive material comprises, for example, a conductive polymer and / or conductive carbon. Alternatively, for example, the gasket (80) may be formed by mixing a conductive polymer and / or conductive carbon with an insulating material.

[0245] In this case, the conductive polymer is a polymer that conducts electricity, and includes, for example, organic polymers. The conductive polymer may have electrical conductivity such as that of a metal, for example. Alternatively, the conductive polymer may have properties such as those of a semiconductor, for example.

[0246] For example, the conductive polymer may include at least one selected from the group consisting of polythiophene-based conductive polymers, polypyrrole, polyphenylene, polyaniline, polyacetylene, polysulfonitride, and combinations of at least two of these.

[0247] Polythiophene-based conductive polymers may include, for example, polyethylenedioxythiophene (PEDT), polyethylenedioxythiophene / polycellulose sulfonate (PEDOT / PCS), etc.

[0248] For example, the conductive polymer has a melting point of 180°C or higher and 300°C or lower. Or, for example, the conductive polymer has a melting point of 200°C or higher and 280°C or lower. Or, for example, the conductive polymer has a melting point of 200°C or higher and 260°C or lower.

[0249] If the melting point of the conductive polymer is less than 180°C, the gasket (80) may melt or be damaged as the formation process of the secondary battery (100) proceeds. Therefore, it is preferable that the melting point of the conductive polymer be 180°C or higher. In addition, if the melting point of the conductive polymer exceeds 300°C, it may be difficult to shape the gasket (80) containing the conductive polymer. Therefore, it is preferable that the melting point of the conductive polymer be 300°C or lower.

[0250] In this way, the gasket (80) can electrically connect the case (20) and the cap plate (60) located on both sides of the gasket (80) by including a conductive material. Additionally, the cap plate (60) can form the same polarity as the case (20). Through this, the secondary battery (100) according to one embodiment of the present invention can prevent the cap plate (60) from corroding even when exposed to an electrolyte.

[0251]

[0252] FIG. 13 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0253] FIG. 14 is a cross-sectional view showing an enlarged view of A in FIG. 4.

[0254] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 12) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0255] For example, the gasket (80) includes an insulating gasket (81) comprising an insulating material; and a coating layer (82) comprising a conductive material coated on at least a portion of the outside of the insulating gasket (81).

[0256] The insulating gasket (81) comprises an insulating material. The insulating gasket (81) forms the basic shape of the gasket (80). For example, the insulating gasket (81) may be provided between the case (20) and the cap plate (60) to seal the space between the case (20) and the cap plate (60).

[0257] At this time, the insulating material may include at least one of, for example, a polyolefin resin, a polyester resin, or a polyether resin. The polyolefin resin may include, for example, a polyethylene resin (PE) or a polypropylene resin (PP). The polyester resin may include, for example, polybutylene terephthalate resin (PBT). The polyether resin may include, for example, polyetheretherketone resin (PEEK).

[0258] The coating layer (82) includes a conductive material. The coating layer (82) enables the gasket (80) to electrically connect the case (20) and the cap plate (60). Accordingly, the coating layer (82) does not need to be formed on the front surface of the insulating gasket (81), but must be formed to electrically connect at least the case (20) and the cap plate (60). For example, the coating layer (82) must be formed continuously without interruption from the case (20) toward the cap plate (60).

[0259] A coating layer (82) is formed on at least a portion of the exterior of the insulating gasket (81). For example, the coating layer (82) may be formed by applying a coating agent containing a conductive material to the insulating gasket (81) and then heating and / or drying it. Alternatively, for example, the coating layer (82) may be formed by spraying a coating liquid containing a conductive material onto the exterior of the insulating gasket (81). However, the methods by which the coating layer (82) may be formed on the exterior of the insulating gasket (81) are not limited thereto.

[0260] At this time, the conductive material includes, for example, at least one of a metal, a conductive polymer, a conductive carbon, a conductive coating material, and a combination thereof.

[0261] The metal includes, for example, at least one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), nickel (Ni), iron (Fe), tungsten (W), and combinations thereof.

[0262] The conductive polymer may include, for example, at least one selected from the group consisting of polythiophene-based conductive polymers, polypyrrole, polyphenylene, polyaniline, polyacetylene, polysulfonitride, and combinations of at least two of these.

[0263] The conductive coating material may include, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or a liquid polymer.

[0264] Meanwhile, if the conductive material contains metal, corrosion may occur in the part of the gasket (80) that is exposed to the outside of the case (20).

[0265] To solve this problem, the secondary battery (100) may further include a protective member (s) comprising an insulating material, which is formed to cover the exposed portion of the gasket (80) exposed to the outside from between the case (20) and the cap plate (60).

[0266] The insulating material included in the protective member(s) may be the same or different from the insulating material included in the insulating gasket (81), for example.

[0267] The protective member(s) may be formed to cover the gasket (80) exposed outside the case (20). For example, the protective member(s) may be formed along the lower end of the case (20), which is outside the case (20) and is the area where the gasket (80) is exposed.

[0268] The protective member(s) can be formed, for example, through a rust prevention process. For example, the protective member(s) can be formed by applying and heating / drying a rust prevention coating agent containing an insulating material while covering the gasket (80).

[0269] In this way, the gasket (80) can electrically connect the case (20) and the cap plate (60) located on both sides of the gasket (80) by including a coating layer (82) coated on the insulating gasket (81). Additionally, the cap plate (60) can form the same polarity as the case (20). Furthermore, the secondary battery (100) can prevent corrosion of the coating layer (82) through a protective member(s). Through this, the secondary battery (100) according to one embodiment of the present invention can prevent the cap plate (60) from corroding even when exposed to an electrolyte. Additionally, the secondary battery (100) can prevent corrosion of the gasket (80) even when the gasket (80) contains metal.

[0270]

[0271] Figure 15 is a cross-sectional view showing an enlarged view of A in Figure 4.

[0272] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 14) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0273] For example, the gasket (80) includes an insulating gasket (81) comprising an insulating polymer; and one or more conductive structures (83) provided inside the insulating gasket (81) and connecting the case (20) and the cap plate (60).

[0274] The conductive structure (83) includes, for example, a conductive material. The conductive material includes, for example, a metal, a carbon-based filler, or a combination thereof.

[0275] Metals include, for example, copper (Cu), nickel (Ni), iron (Fe), SUS, gold (Au), silver (Ag), platinum (Pt), tungsten (W), tin (Sn), lead (Pb), zinc (Zn), etc.

[0276] Carbon-based fillers include, for example, carbon black, carbon fiber, carbon nanotubes, etc.

[0277] A combination of these includes, for example, a mixed material of metal and / or carbon-based filler. Or, a combination of these includes, for example, a material in which the exterior of a metal is coated with a carbon-based filler.

[0278] The gasket (80) may include one or more conductive structures (83). In this case, one side of the conductive structure (83) may be in contact with the inner surface of the case (20) and the other side may be in contact with the outer surface of the cap plate (60).

[0279] For example, the gasket (80) includes a single conductive structure (83). The single conductive structure (83) is inserted into a part of the interior of the insulating gasket (81) and electrically connects the case (20) and the cap plate (60) in that part. In this way, when the gasket (80) includes only one conductive structure (83), the gasket (80) can reduce the overall weight of the secondary battery (100) while allowing the cap plate (60) to have polarity.

[0280] Alternatively, for example, the gasket (80) includes a plurality of conductive structures (83). The plurality of conductive structures (83) are inserted into multiple regions inside the insulating gasket (81) to electrically connect the case (20) and the cap plate (60) in multiple regions. In this way, when the gasket (80) includes a plurality of conductive structures (83), the gasket (80) can stably connect the case (20) and the cap plate (60).

[0281] In this way, the gasket (80) can electrically connect the case (20) and the cap plate (60) located on both sides of the gasket (80) by including a conductive structure (83) inside the insulating gasket (81). Additionally, the cap plate (60) can form the same polarity as the case (20). Through this, the secondary battery (100) according to one embodiment of the present invention can prevent the cap plate (60) from corroding even when exposed to an electrolyte.

[0282]

[0283] As described above, for example, a cap plate (60) according to one embodiment of the present invention is electrically connected to a case (20) and / or a second electrode by a second current collector plate (70). Or, for example, a cap plate (60) according to one embodiment of the present invention is electrically connected to a case (20) and / or a second electrode by a gasket (80).

[0284] Furthermore, for example, a cap plate (60) according to one embodiment of the present invention may be electrically connected to a case (20) and / or a second electrode by a second current collector plate (70) and a gasket (80). Examples thereof will be described below.

[0285]

[0286] FIG. 16 is a cross-sectional view showing an enlarged lower section of a secondary battery according to one embodiment of the present invention.

[0287] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 15) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0288] For example, the secondary battery (100) further includes a second current collector plate (70) (e.g., including the second current collector plate (70) described in FIGS. 3 to 11) and a gasket (80) (e.g., including the gasket (80) described in FIGS. 3 to 15).

[0289] For example, the second current collector plate (70) includes a main body portion (71) connected to the second electrode; and a connecting portion (73) having one side connected to the main body portion (71) and the other side in contact with the upper surface of the cap plate (60). Additionally, for example, the second current collector plate (70) may further include a leg portion (72) that extends radially from the main body portion (71) toward the inner circumferential surface of the case (20) to electrically connect the main body portion (71) and the case (20).

[0290] For example, the gasket (80) can electrically connect the case (20) and the cap plate (60). By connecting the case (20) and the cap plate (60) connected to the second electrode, the gasket (80) can cause the cap plate (60) to have the same polarity as the second electrode. Through this, the secondary battery (100) can prevent corrosion of the cap plate (60).

[0291] For example, the gasket (80) includes a conductive material. For example, the conductive material includes a metal, a conductive polymer, a conductive carbon and / or a combination thereof.

[0292] In this way, the cap plate (60) according to one embodiment of the present invention may have polarity through the second current collector plate (70) and the gasket (80). Even if one of the second current collector plate (70) and the gasket (80) is damaged, the cap plate (60) may not lose its electrical connection with the case (20). Additionally, the secondary battery (100) can more efficiently prevent internal corrosion.

[0293]

[0294] FIG. 17 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0295] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 16) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0296] For example, the secondary battery (100) further includes a second current collector plate (70) (e.g., including the second current collector plate (70) described in FIGS. 3 to 11 and FIG. 16) and a gasket (80) (e.g., including the gasket (80) described in FIGS. 3 to 15).

[0297] For example, the second current collector plate (70) includes a main body portion (71) connected to the second electrode; and a connecting portion (73) having one side connected to the main body portion (71) and the other side in contact with the upper surface of the cap plate (60). Additionally, for example, the second current collector plate (70) may further include a leg portion (72) that extends radially from the main body portion (71) toward the inner circumferential surface of the case (20) to electrically connect the main body portion (71) and the case (20).

[0298] For example, the gasket (80) includes an insulating gasket (81) comprising an insulating material; and a coating layer (82) comprising a conductive material coated on at least a portion of the outside of the insulating gasket (81).

[0299] The insulating gasket (81) comprises an insulating material. The insulating gasket (81) forms the basic shape of the gasket (80). For example, the insulating gasket (81) may be provided between the case (20) and the cap plate (60) to seal the space between the case (20) and the cap plate (60).

[0300] For example, the insulating material may include at least one of a polyolefin resin, a polyester resin, and a polyether resin. The polyolefin resin may include, for example, a polyethylene resin (PE) or a polypropylene resin (PP). The polyester resin may include, for example, polybutylene terephthalate resin (PBT). The polyether resin may include, for example, polyetheretherketone resin (PEEK).

[0301] The coating layer (82) includes a conductive material. The coating layer (82) enables the gasket (80) to electrically connect the case (20) and the cap plate (60). Accordingly, the coating layer (82) does not need to be formed on the front surface of the insulating gasket (81), but must be formed to electrically connect at least the case (20) and the cap plate (60). For example, the coating layer (82) must be formed continuously without interruption from the case (20) toward the cap plate (60).

[0302] A coating layer (82) is formed on at least a portion of the exterior of the insulating gasket (81). For example, the coating layer (82) may be formed by applying a coating agent containing a conductive material to the insulating gasket (81) and then heating and / or drying it. Alternatively, for example, the coating layer (82) may be formed by spraying a coating liquid containing a conductive material onto the exterior of the insulating gasket (81). However, the methods by which the coating layer (82) may be formed on the exterior of the insulating gasket (81) are not limited thereto.

[0303] At this time, the conductive material includes, for example, at least one of a metal, a conductive polymer, a conductive carbon, a conductive coating material, and a combination thereof.

[0304] The metal includes, for example, at least one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), nickel (Ni), iron (Fe), tungsten (W), and combinations thereof.

[0305] The conductive polymer may include, for example, at least one selected from the group consisting of polythiophene-based conductive polymers, polypyrrole, polyphenylene, polyaniline, polyacetylene, polysulfonitride, and combinations of at least two of these.

[0306] The conductive coating material may include, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or a liquid polymer.

[0307] In this way, the cap plate (60) according to one embodiment of the present invention may have polarity through the second current collector plate (70) and the gasket (80). Even if one of the second current collector plate (70) and the gasket (80) is damaged, the cap plate (60) may not lose its electrical connection with the case (20). Additionally, the secondary battery (100) can more efficiently prevent internal corrosion.

[0308]

[0309] FIG. 18 is a cross-sectional view showing an enlarged view of the lower part of a secondary battery according to one embodiment of the present invention.

[0310] A secondary battery (100) according to one embodiment of the present invention (e.g., including the secondary battery (100) described in FIGS. 1 to 17) comprises: an electrode assembly (10) including a first electrode and a second electrode; a case (20) housing the electrode assembly (10); a cap plate (60) covering the opening of the case (20) and electrically connected to the second electrode; and a gasket (80) sealing the opening of the case (20) while wrapping the cap plate (60) along the outer surface of the cap plate (60).

[0311] For example, the secondary battery (100) further includes a second current collector plate (70) (e.g., including the second current collector plate (70) described in FIGS. 3 to 11 and FIG. 16) and a gasket (80) (e.g., including the gasket (80) described in FIGS. 3 to 15).

[0312] For example, the second current collector plate (70) includes a main body portion (71) connected to the second electrode; and a connecting portion (73) having one side connected to the main body portion (71) and the other side in contact with the upper surface of the cap plate (60). Additionally, for example, the second current collector plate (70) may further include a leg portion (72) that extends radially from the main body portion (71) toward the inner circumferential surface of the case (20) to electrically connect the main body portion (71) and the case (20).

[0313] For example, the gasket (80) includes an insulating gasket (81) comprising an insulating polymer; and one or more conductive structures (83) provided inside the insulating gasket (81) and connecting the case (20) and the cap plate (60).

[0314] The conductive structure (83) includes, for example, a conductive material. The conductive material includes, for example, a metal, a carbon-based filler, or a combination thereof.

[0315] Metals include, for example, copper (Cu), nickel (Ni), iron (Fe), SUS, gold (Au), silver (Ag), platinum (Pt), tungsten (W), tin (Sn), lead (Pb), zinc (Zn), etc.

[0316] Carbon-based fillers include, for example, carbon black, carbon fiber, carbon nanotubes, etc.

[0317] A combination of these includes, for example, a mixed material of metal and / or carbon-based filler. Or, a combination of these includes, for example, a material in which the exterior of a metal is coated with a carbon-based filler.

[0318] In this way, the cap plate (60) according to one embodiment of the present invention may have polarity through the second current collector plate (70) and the gasket (80). Even if one of the second current collector plate (70) and the gasket (80) is damaged, the cap plate (60) may not lose its electrical connection with the case (20). Additionally, the secondary battery (100) can more efficiently prevent internal corrosion.

[0319]

[0320] FIGS. 16 to 18 describe examples in which a cap plate (60) is electrically connected to a case (20) and / or a second electrode by means of a second current collector plate (70) and a gasket (80). However, embodiments of a secondary battery (100) according to one embodiment of the present invention are not limited thereto. For example, as shown in FIG. 11, the cap plate (60) may be directly connected to the case (20) through the side of the edge portion. In addition, the gasket (80) covering the upper and / or lower surface of the edge portion of the cap plate (60) may include a conductive material, as described in FIG. 12. Thus, the cap plate (60) may be electrically connected to the case (20) and / or the second electrode by a combination of at least one of the second current collector plates (70) described in FIGS. 5 to 11 and at least one of the gaskets (80) described in FIG. 12 to 15.

[0321]

[0322] FIG. 19 is a block diagram illustrating the components of a secondary battery design system according to one embodiment of the present invention.

[0323] In FIG. 19, 2000 represents a secondary battery design system according to one embodiment of the present invention. The secondary battery design system (2000) designs a secondary battery (100) as described, for example, in FIGS. 1 to 18. Alternatively, the secondary battery design system (2000) designs a battery pack (1000) as described, for example, in FIGS. 1 to 18. For example, the secondary battery design system (2000) can design the secondary battery (100) so that corrosion does not occur inside the secondary battery (100).

[0324] The secondary battery design system (2000) includes memory (2100) and a processor (2200).

[0325] The memory (2100) stores information about the material group of the cap plate (60). For example, the memory (2100) stores information about the material group including a first material group and a second material group. In this case, the information about the material group includes enumerated examples of materials included in each of the first material group and the second material group. Alternatively, the information about the material group stores information about the criteria for dividing the first material group and the second material group. In this case, the criteria for dividing the first material group and the second material group may be set based on the material included in the case (20).

[0326] The processor (2200) controls all or some of the components included in the secondary battery design system (2000). For example, the processor (2200) may be formed in the form of an MCU, a CPU, etc.

[0327] The processor (2200) determines the polarity of the cap plate (60) so that the cap plate (60) does not rust based on the material group of the cap plate (60).

[0328] For example, the processor (2200) ensures that the cap plate (60) does not have polarity if the group of materials included in the cap plate (60) corresponds to the first group of materials. At this time, the first group of materials includes, for example, at least one selected from the group consisting of aluminum (Al), SUS, and combinations thereof.

[0329] In this case, for example, the processor (2200) designs the structure of the secondary battery (100) so that the cap plate (60) is not connected to the case (20). Also, in this case, for example, the processor (2200) designs the structure of the secondary battery (100) so that the cap plate (60) is not connected to the second current collector plate (70). Through this, the processor (2200) can propose a structure of the secondary battery (100) in which the cap plate (60) is insulated from the second electrode.

[0330] A secondary battery design system (2000) according to one embodiment of the present invention can provide a method to prevent corrosion even when the cap plate (60) includes a material included in the first material group.

[0331] Alternatively, for example, the processor (2200) causes the cap plate (60) to have polarity if the group of materials included in the cap plate (60) corresponds to a second group of materials. At this time, the second group of materials includes, for example, at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof. Alternatively, the second group of materials includes, for example, a magnetic material.

[0332] In this case, for example, the processor (2200) designs a structure of a secondary battery (100) in which a cap plate (60) can be connected to a second current collector plate (70) and / or a case (20). Through this, the processor (2200) can propose a structure of a secondary battery (100) in which the cap plate (60) is connected to a second electrode. For example, the processor (2200) can propose a structure of a secondary battery (100) according to the structure described in FIGS. 5 to 18 or a combination thereof.

[0333] Through this, a secondary battery design system (2000) according to one embodiment of the present invention can provide a method to prevent corrosion even when the cap plate (60) includes a material included in the second material group.

[0334]

[0335] Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom.

[0336] Therefore, the technical scope of protection of the present invention should be determined by the following patent claims.

[0337]

[0338] A secondary battery, a battery pack including a secondary battery, and / or a secondary battery design system according to one embodiment of the present invention are industrially available.

Claims

An electrode assembly comprising a first electrode and a second electrode; A case for housing the above electrode assembly; A cap plate covering the opening of the above case and electrically connected to the second electrode; and A secondary battery comprising: a gasket that seals the opening of the case while wrapping the cap plate along the outer surface of the cap plate. In Article 1, The above-mentioned cap plate comprises at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof, in a secondary battery. In Article 1, The secondary battery comprises a second current collector plate located between the electrode assembly and the cap plate and connected to the second electrode; A secondary battery comprising: a main body portion connected to the second electrode; and a leg portion extending radially from the main body portion toward the inner surface of the case to electrically connect the main body portion and the case. In Paragraph 3, A secondary battery further comprising: a second current collector plate having one side connected to the main body and the other side in contact with the upper surface of the cap plate. In Article 4, The other side of the above connection part is a secondary battery extending between the gasket and the cap plate. In Paragraph 3, The above gasket seals the opening of the case while wrapping at least one of the upper surface and the side surface of the edge of the cap plate, and The above leg portion is a secondary battery extending between the gasket and the case. In Paragraph 3, The above gasket seals the opening of the case while wrapping at least one of the side and bottom surfaces of the edge of the cap plate, and The above leg portion is a secondary battery extending between the upper surface of the edge of the cap plate and the case. In Paragraph 3, The above gasket seals the opening of the case while wrapping at least one of the upper and lower surfaces of the edge of the cap plate, and The above leg portion is a secondary battery extending between the gasket and the case. In Paragraph 3, The above cap plate is a secondary battery comprising a magnetic material. In Article 1, The above gasket is a secondary battery that electrically connects the above case and the above cap plate. In Article 1, The above gasket is a secondary battery comprising a conductive polymer or conductive carbon. In Article 1, The above gasket is, Insulating gasket comprising an insulating material; and A secondary battery comprising: a coating layer comprising a conductive material coated on at least a portion of the exterior of the insulating gasket. In Article 12, The secondary battery further comprises: a protective member comprising an insulating material, which is formed to cover an exposed portion of the gasket exposed to the outside from between the case and the cap plate, when the conductive material includes a metal. In Article 1, The above gasket is, Insulating gasket comprising an insulating material; and A secondary battery comprising: one or more conductive structures formed by penetrating the interior of the insulating gasket and connecting the case and the cap plate. In Article 1, The secondary battery comprises: a main body portion connected to the second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which contacts the upper surface of the cap plate; and further comprises a second current collector plate located between the electrode assembly and the cap plate. The above gasket is a secondary battery comprising a conductive material. In Article 1, The secondary battery comprises: a main body portion connected to the second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which contacts the upper surface of the cap plate; and further comprises a second current collector plate located between the electrode assembly and the cap plate. A secondary battery comprising: an insulating gasket comprising an insulating material; and a coating layer comprising a conductive material coated on at least a portion of the exterior of the insulating gasket. In Article 1, The secondary battery comprises: a main body portion connected to the second electrode; and a connecting portion, one side of which is connected to the main body portion and the other side of which contacts the upper surface of the cap plate; and further comprises a second current collector plate located between the electrode assembly and the cap plate. A secondary battery comprising: an insulating gasket comprising an insulating material; and one or more conductive structures formed by penetrating the interior of the insulating gasket and connecting the case and the cap plate. Multiple secondary batteries; and A housing for housing the plurality of secondary batteries; comprising, The above secondary battery is, A cap plate covering the opening of the above case and electrically connected to the second electrode; and A gasket that seals the opening of the case while wrapping the cap plate along the outer surface of the cap plate; comprising Battery pack. A secondary battery design system for designing a secondary battery comprising: an electrode assembly including a first electrode and a second electrode; a case housing the electrode assembly; and a cap plate covering an opening of the case. A processor that determines the polarity of the cap plate according to the material group of the cap plate; comprising, The above processor is, Designing the secondary battery such that if the material group is a first material group, the cap plate is insulated from the second electrode, and if the material group is a second material group, the cap plate is electrically connected to the second electrode. Secondary battery design system. In Article 19, A secondary battery design system comprising at least one selected from the group consisting of steel, copper (Cu), nickel (Ni), SUS, and combinations thereof, wherein the second material group above comprises steel, copper (Cu), nickel (Ni), stainless steel (SUS), and combinations thereof.

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