Secondary battery, secondary battery module, and secondary battery pack

Abstract

The present disclosure relates to a secondary battery. The described technical problem is solved by providing a secondary battery including an upper cover having improved quality. To this end, the present disclosure provides a secondary battery including a case, an electrode assembly accommodated in the case, and a cover assembly blocking a portion of the case and sealing the electrode assembly, wherein the cover assembly includes an upper cover including aluminum (Al) as a main component thereof and magnesium in an amount of 5 wt% or more.

Description

Technical Field

[0001] This disclosure relates to a secondary battery including a magnesium-containing top cover, a secondary battery module, and a secondary battery pack. Background Technology

[0002] Unlike non-rechargeable primary batteries, secondary batteries are rechargeable and dischargeable. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources and rechargeable batteries for driving motors in hybrid vehicles, electric vehicles, etc. Such secondary batteries include electrodes containing positive and / or negative electrodes, electrode assemblies containing the electrodes, a housing accommodating the electrode assemblies, and electrode terminals connected to the electrode assemblies.

[0003] With technological advancements, there is a demand for high-capacity rechargeable batteries. Therefore, multiple rechargeable batteries can be electrically connected and used. For example, rechargeable batteries can be applied to electronic devices in the form of rechargeable battery modules comprising multiple rechargeable batteries and / or rechargeable battery packs comprising multiple rechargeable battery modules. Here, the electronic devices are those requiring high output and / or high capacity, and examples of electronic devices include electric vehicles, etc.

[0004] Simultaneously, this secondary battery incorporates highly reactive materials to enable multiple charge-discharge cycles. Optionally, the secondary battery can be assembled into electronic devices and applied in locations closely related to daily life. Therefore, ensuring the stability of the secondary battery is crucial.

[0005] However, when multiple secondary batteries are electrically connected and used together, problems occurring in one secondary battery can, in some cases, transfer in series to adjacent secondary batteries. In such situations, the secondary batteries may successively ignite or explode, posing a significant risk.

[0006] Therefore, it is necessary to prevent the spread of heat and / or fire or explosion between secondary batteries.

[0007] The information disclosed above in the art used as the background of this invention is only for improving the understanding of the background of this invention, and therefore may include information that does not constitute prior art. Summary of the Invention

[0008] [Technical Issues] The present invention relates to a secondary battery, a secondary battery module, and a secondary battery pack, including a top cover for preventing the secondary battery from exploding.

[0009] The present invention relates to a secondary battery including a top cover that ensures weldability, a secondary battery module, and a secondary battery pack.

[0010] The present invention relates to a secondary battery, a secondary battery module, and a secondary battery pack, including a top cover thereon that does not rust and / or reduces rusting.

[0011] The present invention relates to a secondary battery, a secondary battery module, and a secondary battery pack, including a top cover having a reduced weight compared to the prior art.

[0012] However, the purpose of this invention is not limited to the purposes mentioned above, and other unmentioned purposes should be clearly understood by those skilled in the art from the following description of the invention.

[0013] [Technical Solution] One embodiment of the present invention for achieving the above objectives provides a secondary battery comprising: a housing; an electrode assembly housed within the housing; and a cover assembly that blocks an opening in the housing and seals the electrode assembly, wherein the cover assembly includes an upper cover comprising aluminum (Al) as its main component and magnesium in an amount of 5 wt% or greater.

[0014] An embodiment of the present invention for achieving the above objectives provides a secondary battery module comprising: a plurality of secondary batteries; and a housing for accommodating the plurality of secondary batteries, wherein at least some of the plurality of secondary batteries each comprises: a housing; an electrode assembly housed within the housing; and a cover assembly that blocks an opening in the housing and seals the electrode assembly, and the cover assembly comprises an upper cover comprising aluminum (Al) as its main component and magnesium in an amount of 5 wt% or greater.

[0015] An embodiment of the present invention for achieving the above objectives provides a secondary battery pack, the secondary battery pack comprising: the aforementioned secondary battery modules, configured as a plurality of secondary battery modules; and a housing for accommodating the plurality of secondary battery modules.

[0016] [Beneficial Effects] According to the present invention, it is possible to provide a secondary battery, a secondary battery module, and a secondary battery pack, including a cover for preventing the secondary battery from exploding.

[0017] According to the present invention, it is possible to provide a secondary battery including a cover with improved quality, a secondary battery module, and a secondary battery pack.

[0018] According to the present invention, it is possible to provide a secondary battery including a top cover that ensures weldability, a secondary battery module, and a secondary battery pack.

[0019] According to the present invention, it is possible to provide a secondary battery, a secondary battery module, and a secondary battery pack, including a top cover with a reduced weight compared to the prior art.

[0020] According to the present invention, it is possible to provide a secondary battery, a secondary battery module, and a secondary battery pack, including a top cover on which rust does not occur and / or rust is delayed.

[0021] According to another aspect of the present invention, it is possible to provide a secondary battery module that uses a secondary battery with an improved structure, a secondary battery pack including the secondary battery module, and / or a vehicle including the secondary battery pack.

[0022] However, the beneficial effects that can be obtained by the present invention are not limited to those mentioned above, and those skilled in the art should clearly understand from the above description of the invention that other beneficial effects have not been mentioned. Attached Figure Description

[0023] The accompanying drawings illustrate preferred embodiments of the invention by way of example and, together with the detailed description of the invention given below, are intended to further understand the technical concept of the invention. Therefore, the invention should not be interpreted solely based on the contents of these drawings.

[0024] Figure 1 This is a schematic cross-sectional view of a cylindrical secondary battery according to an embodiment of the present invention.

[0025] Figure 2 This is a cross-sectional view showing the upper part of a cylindrical secondary battery according to an embodiment of the present invention.

[0026] Figure 3 This is a cross-sectional view of a cover assembly according to an embodiment of the present invention.

[0027] Figure 4 This is a top view of the top cover according to an embodiment of the present invention.

[0028] Figure 5 This is a cross-sectional view of the top cover according to an embodiment of the present invention.

[0029] Figure 6 It is a graph used to describe the effect of the cover according to an embodiment of the present invention.

[0030] Figure 7 This is a schematic cross-sectional view of a secondary battery module according to an embodiment of the present invention.

[0031] Figure 8 This is a view showing a secondary battery pack according to an embodiment of the present invention.

[0032] Figure 9 This is a view showing a secondary battery pack according to an embodiment of the present invention.

[0033] Figure 10This is a view showing a vehicle body and vehicle body components according to an embodiment of the present invention. Detailed Implementation

[0034] In the following, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in this specification and claims should not be construed as limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical concept of the present disclosure, based on the principle that the inventor can appropriately define the concepts of the terms in order to best describe his or her disclosure. Therefore, it will be understood that the embodiments described herein and the constructions shown in the accompanying drawings are merely some of the most exemplary embodiments of the disclosure and do not represent all the technical concepts disclosed, and various equivalents and modifications that can replace them may exist at the time of submission.

[0035] Furthermore, when the terms “including or comprising” and / or variations thereof are used herein, it indicates the presence of the mentioned shapes, quantities, steps, operations, components, elements and / or groups thereof, and is not intended to exclude the presence or addition of one or more other shapes, quantities, operations, components, elements and / or groups thereof.

[0036] Additionally, to aid in understanding the disclosure, the drawings are not drawn to scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to the same components in different embodiments.

[0037] The statement that two objects used for comparison are “identical” means “substantially identical.” Therefore, substantially identical can include deviations considered low in the art (e.g., less than 5% deviation). Additionally, the uniformity of parameters over a given region can refer to uniformity from an average perspective.

[0038] Although terms such as "first," "second," etc., are used to describe various components, the components are not limited by these terms. These terms are only used to distinguish one component from another, and unless otherwise specifically stated, it will be understood that a first component can also be a second component.

[0039] Throughout this specification, unless otherwise specifically stated, each element may be singular or plural.

[0040] When any construct is placed "on (below)" or "above (or below)" a component, it can mean not only that the any construct is placed in contact with the top (or bottom) of the component, but also that other constructs can be placed between the component and the any construct placed on (or below) the component.

[0041] Additionally, when a component is described as being "on" another component, "connected to", or "combined to" another component, the components can be directly connected or combined with each other. However, it should be understood that other components can be "placed" between the components, or the components can be "connected", "combined", or "linked" through another component.

[0042] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of “may” refers to “one or more embodiments of this disclosure.” Expressions such as “one or more” and “at least one” modify the entire list of elements when preceding a list of elements, without modifying individual elements within that list.

[0043] Throughout this specification, unless otherwise stated to the contrary, “A and / or B” means A, B, or A and B. That is, “and / or” includes any or all combinations of the listed items.

[0044] When “C to D” is stated, unless otherwise stated, it means greater than or equal to C and less than or equal to D. When a list of elements A, B and C is specified using phrases such as “at least one of A, B and C”, “at least one of A, B or C”, “at least one of the group selected from A, B and C”, or “at least one of A, B and C”, the phrase may refer to any suitable combination and all suitable combinations.

[0045] The term “use” may be considered synonymous with the term “utilize”. As used in this specification, the terms “substantially,” “about,” and other similar terms are used as approximations rather than terms of degree and are intended to take into account the inherent biases of measurements or calculations as recognized by those skilled in the art.

[0046] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, first component, first region, first layer, or first portion discussed below may be referred to as a second element, second component, second region, second layer, or second portion.

[0047] For ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein to describe the relationship between one element or feature as shown in the accompanying drawings and another element(s). It will be understood that, in addition to the orientation depicted in the drawings, the spatial relative terms are also intended to cover different orientations of the device during use or operation. For example, when an element or feature in the drawings is flipped, an element described as “below” or “under” becomes “above” or “upper.” Therefore, the term “below” can include both upward and downward directions.

[0048] The terminology used in this specification is intended to describe embodiments of this disclosure and is not intended to limit this disclosure.

[0049] Figure 1 This is a schematic cross-sectional view of a cylindrical secondary battery according to an embodiment of the present invention.

[0050] Figure 2 This is a schematic cross-sectional view of the upper part of a cylindrical secondary battery according to an embodiment of the present invention.

[0051] like Figure 1 As shown, a cylindrical lithium-ion secondary battery 100 according to an embodiment of the present invention may include a cylindrical housing 50, an electrode assembly 40, and a cover assembly 300. Furthermore, in some cases, the cylindrical lithium-ion secondary battery 100 may also include a center pin 70. Additionally, because the cover assembly 300 in the secondary battery 100 according to an embodiment of the present invention also performs a current interruption operation, in some cases, the cover assembly 300 may be referred to as a "current interruption device".

[0052] The cylindrical housing 50 may include a generally circular bottom 51 and cylindrical sidewalls 52 extending upwards from the circumference of the bottom 51 for a predetermined length. During the manufacturing process of the secondary battery, the upper portion 101 of the cylindrical housing 50 is open. Therefore, during the assembly process of the secondary battery, the electrode assembly 40 and the center pin 70 can be inserted into the cylindrical housing 50 along with the electrolyte. For example, although not limited thereto, the cylindrical housing 50 may be made of steel, stainless steel, aluminum, aluminum alloys, or equivalents thereof.

[0053] In addition, the cylindrical housing 50 may include: a rolled edge portion 110 that is recessed inward around the cover assembly 300 at the lower part of the cover assembly 300 to prevent the cover assembly 300 from falling to the outside; and a pressing portion 120 that is bent inward at the upper part of the rolled edge portion 110.

[0054] Electrode assembly 40 can be housed within a cylindrical housing 50. Electrode assembly 40 may include: a negative electrode plate 20, in which a negative electrode current collector is coated with a negative electrode active material (e.g., graphite, carbon, etc.); a positive electrode plate 10, in which a positive electrode current collector is coated with a positive electrode active material (e.g., transition metal oxides (LiCoO2, LiNiO2, LiMn2O4, etc.)); and a separator 30 positioned between the negative electrode plate 20 and the positive electrode plate 10 to prevent short circuits and allow only lithium ions to move. Furthermore, the negative electrode plate 20, the positive electrode plate 10, and the separator 30 may be wound into a generally cylindrical shape. Here, for example, although not limited thereto, the negative electrode current collector may be made of copper (Cu) foil, the positive electrode current collector may be made of aluminum (Al) foil, and the separator may be made of polyethylene (PE) or polypropylene (PP).

[0055] Furthermore, a negative electrode tab (not shown) extending downwards by a predetermined length can be soldered to the negative electrode plate 20, and a positive electrode tab 11 extending upwards by a predetermined length can be soldered to the positive electrode plate 10, and vice versa. Additionally, although not limited to this, the negative electrode tab can be made of copper (Cu) or nickel (Ni), and the positive electrode tab 11 can be made of aluminum (Al).

[0056] Furthermore, the negative electrode terminal of the electrode assembly 40 can be soldered to the bottom 51 of the cylindrical housing 50. Therefore, the cylindrical housing 50 can be used as a negative electrode. Conversely, the positive electrode terminal 11 can be soldered to the bottom 51 of the cylindrical housing 50, and in this case, the cylindrical housing 50 can be used as a positive electrode.

[0057] Additionally, a first insulating plate (not shown) integrated into the cylindrical housing 50, having a first lower hole (not shown) formed in the center and a second lower hole (not shown) formed on the outer side, can be placed between the electrode assembly 40 and the bottom 51. The first insulating plate serves to prevent electrical contact between the electrode assembly 40 and the bottom 51 of the cylindrical housing 50. Specifically, the first insulating plate serves to prevent electrical contact between the positive electrode plate 10 of the electrode assembly 40 and the bottom 51. Here, when a large amount of gas is generated due to an anomaly in the secondary battery, the first lower hole allows the gas to move rapidly upward through the central pin 70, while the second lower hole allows the negative electrode tab to pass through and be soldered to the bottom 51.

[0058] Furthermore, a second insulating plate 80, which is incorporated into the cylindrical housing 50 and has a first upper hole (not shown) formed in the center and a plurality of second holes (not shown) formed on the outer side, can be placed between the electrode assembly 40 and the cover assembly 300. The second insulating plate 80 is used to prevent electrical contact between the electrode assembly 40 and the cover assembly 300. Specifically, the second insulating plate 80 is used to prevent electrical contact between the negative electrode plate 20 of the electrode assembly 40 and the cover assembly 300. Here, the first hole allows gas to move rapidly to the cover assembly 300 in the event of a large amount of gas generated due to an anomaly in the secondary battery, and the second hole allows the positive electrode tab to pass through and be soldered to the cover assembly 300. The remaining second holes allow electrolyte to flow rapidly into the electrode assembly 40 during the electrolyte injection process.

[0059] In addition, the diameter of the first hole in each of the first and second insulating plates 80 is formed to be smaller than the diameter of the center pin 70 to prevent the center pin 70 from making electrical contact with the bottom 51 of the cylindrical housing 50 or the cover assembly 300 due to external impact.

[0060] The center pin 70 is in the form of a hollow cylindrical tube and can be substantially attached to the center of the electrode assembly 40. For example, although not limited thereto, the center pin 70 can be made of steel, stainless steel, aluminum, aluminum alloy, or polybutylene terephthalate. The center pin 70 is used to suppress deformation of the electrode assembly 40 during the charging and discharging of the secondary battery and serves as a channel for the movement of gas generated in the secondary battery. Of course, in some cases, the center pin 70 can be omitted.

[0061] The cover assembly 300 includes an upper cover 200. The cover assembly 300 may also include at least one of a lower cover, a vent, and an insulator. See below for further details. Figure 3 The cover assembly 300 will be described in more detail below. The cover assembly 300 is coupled to the opening 101 of the housing 50 and allows the electrode assembly 40 to be sealed within the housing 50.

[0062] The rolled edge 110 is formed to protrude from the outside inward along the outer periphery of the housing 50 between the electrode assembly 40 and the gasket 130. The rolled edge 110 prevents the electrode assembly 40 from moving upward and downward.

[0063] The crimping portion 120 presses the cap assembly 300 into the upper part of the opening 101 of the housing 50, allowing the cap assembly 300 to seal the housing 50. For this purpose, the crimping portion 120 can be formed to bend from the upper end of the housing 50 toward the inside of the housing 50.

[0064] Additionally, the secondary battery 100 according to one embodiment of the present invention may further include a pressing portion (not shown) formed in the form of a groove in a portion of the crimping portion 120. In this way, the secondary battery 100 may also enhance the adhesion between the housing 50, the cover assembly 300, and the gasket 130.

[0065] Here, a gasket 130 is disposed between the housing 50 and the cover assembly 300. The gasket 130 allows the housing 50, which serves as a negative electrode, and the cover assembly 300, which serves as a positive electrode, to be insulated from each other. For this purpose, the gasket 130 includes an insulating material.

[0066] However, the present invention is not limited to the above description, and the shell can be constructed in various other shapes, such as a circular shape or a bag shape. Furthermore, the shell can be made of metals such as aluminum, aluminum alloys, or nickel-plated steel, or of the laminated film or plastic constituting the bag.

[0067] Meanwhile, as described above, the electrode assembly 40 includes a negative electrode formed by a negative electrode plate 20, a positive electrode formed by a positive electrode plate 10, and a diaphragm 30 positioned between the negative electrode and the positive electrode. Furthermore, the electrode assembly 40, together with an electrolyte (not shown), is stored in a cylindrical housing 50. The electrode assembly 40 and the electrolyte will be described below.

[0068] As the positive electrode active material, compounds capable of reversibly inserting and deintercalating lithium (lithium-intercalating compounds) can be used. Specifically, a composite oxide of lithium and one or more metals selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0069] The composite oxide can be a lithium transition metal composite oxide, and specific examples may include lithium nickel oxide, lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate compound, cobalt-free nickel manganese oxide, or combinations thereof.

[0070] As an example, a composite oxide can be a compound represented by any of the following chemical formulas: Li a A1 b X b O2 c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn2 b X b O4 c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni1 b c Co b X c O2 α Dα (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni1 b c Mn b X c O2 α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn1 b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1- g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3 f) Fe2(PO4)3 (0≤f≤2); Li a FePO4 (0.90≤a≤1.8).

[0071] In the above chemical formulas, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, 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 L 1 It is Mn, Al, or a combination thereof.

[0072] The positive electrode for a lithium secondary battery 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 additive.

[0073] With respect to 100 wt% of the positive electrode active material layer, the content of the positive electrode active material may be in the range of 90 wt% to 99.5 wt%, and with respect to 100 wt% of the positive electrode active material layer, the content of each of the binder and the conductive additive may be in the range of 0.5 wt% to 5 wt%.

[0074] Al may be used as the current collector, but the present disclosure is not limited thereto.

[0075] The negative electrode active material includes a material capable of reversibly inserting / extracting lithium ions, lithium metal, a lithium metal alloy, a material capable of doping and de-doping lithium, or a transition metal oxide.

[0076] The material capable of reversibly inserting / extracting lithium ions is a carbon-based negative electrode active material, and may include, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon may include graphite (such as natural graphite or artificial graphite), and examples of amorphous carbon may include soft carbon, hard carbon, mesophase pitch carbide, and calcined coke.

[0077] A Si-based negative electrode active material or a Sn-based negative electrode active material may be used as the material capable of doping and de-doping lithium. The Si-based negative electrode active material may be silicon, a silicon-carbon composite, SiO x (0 < x < 2), a Si-based alloy, or a combination thereof.

[0078] The silicon-carbon composite may be a composite of silicon and amorphous carbon. According to one embodiment, the silicon-carbon composite may have a form including silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0079] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core including crystalline carbon and silicon particles and an amorphous carbon coating layer positioned on the surface of the core.

[0080] The negative electrode for the lithium secondary battery 100 may include a current collector and a negative electrode active material layer positioned on the current collector. The negative electrode active material layer may include a negative electrode active material, and may further include a binder and / or a conductive additive.

[0081] For example, the negative electrode active material layer may include the negative electrode active material in an amount in the range of 90 wt% to 99 wt%, include the binder in an amount in the range of 0.5 wt% to 5 wt%, and include the conductive additive in an amount in the range of 0 wt% to 5 wt%.

[0082] As a binder, non-aqueous binders, aqueous binders, dry binders, or combinations thereof can be used. When an aqueous binder is used as the negative electrode binder, it may also include cellulose compounds capable of imparting viscosity.

[0083] As the negative electrode current collector, one selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, polymer substrate coated with conductive metal, or a combination thereof can be used.

[0084] The electrolyte used in the lithium secondary battery 100 includes a non-aqueous organic solvent and a lithium salt.

[0085] Non-aqueous organic solvents serve as the medium through which ions participating in the electrochemical reactions of a battery can move.

[0086] Non-aqueous organic solvents can be carbonate solvents, ester solvents, ether solvents, ketone solvents or alcohol solvents, aprotic solvents or combinations thereof, and can be used alone or in combination with two or more of the above.

[0087] In addition, when using carbonate solvents, cyclic carbonates and chain carbonates can be mixed and used.

[0088] Depending on the type of lithium secondary battery 100, a separator may exist between the positive and negative electrodes. Multilayer films of polyethylene, polypropylene, polyvinylidene fluoride, or two or more of these can be used as the separator.

[0089] The diaphragm 30 may include a porous substrate and a coating layer positioned on one or both surfaces of the porous substrate and including an organic material, an inorganic material, or a combination thereof.

[0090] Organic materials may include polymers such as polyvinylidene fluoride or (meth)acrylic acid polymers.

[0091] Inorganic materials may include, but are not limited to, 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.

[0092] Organic and inorganic materials can exist either mixed in a single coating layer or stacked as coating layers comprising organic materials and coating layers comprising inorganic materials.

[0093] Reference above Figure 1 and Figure 2A lithium secondary battery 100 according to an embodiment of the present invention has been described. The cover assembly 300 of the secondary battery 100, which is coupled to the opening 101 of the cylindrical housing 50 and seals the cylindrical housing 50, will now be described.

[0094] At the same time, despite the above references Figure 1 and Figure 2 An example of the secondary battery 100 (or its casing 50) being formed in a cylindrical shape has been described, but the shape of the secondary battery 100 according to one embodiment of the invention is not limited thereto. The secondary battery 100 may have any other shape, such as a prismatic shape, a pouch shape, or a coil shape. Furthermore, the casing of the secondary battery 100 may be made of a metal such as aluminum, aluminum alloy, or nickel-plated steel, a laminate constituting the pouch, or plastic.

[0095] Similarly, the cover assembly 300 attached to the housing of the secondary battery 100 can have any shape other than a circular shape, as long as the shape allows the cover assembly 300 to be attached to the housing of the secondary battery 100 and to seal the housing.

[0096] Figure 3 This is a cross-sectional view of a cover assembly according to an embodiment of the present invention.

[0097] For example, the above reference Figure 1 and Figure 2 The described secondary battery 100 includes a housing 50, an electrode assembly 40, and a cover assembly 300. (See reference...) Figure 3 Detailed description of cover assembly 300.

[0098] According to one embodiment of the present invention, the cover assembly 300 is coupled to the opening of the housing 50 and seals the housing 50.

[0099] The cover assembly 300 seals the cylindrical housing 50 and / or prevents heat transfer to adjacent battery cells or prevents the secondary battery 100 from exploding. Furthermore, the cover assembly 300 can be electrically connected to electrodes extending from the electrode assembly 40 (e.g., see reference 1). Figure 1 and Figure 2 (Description of the negative or positive electrode).

[0100] For this purpose, the cover assembly 300 includes an upper cover 200. Additionally, the cover assembly 300 may also include a lower cover 310, a vent 320, and / or an insulator 330. Furthermore, the cover assembly 300 may also include a sub-plate (not shown).

[0101] The upper cover 200 can be positioned at the uppermost side of the cover assembly 300. The upper cover 200 is formed to convex upward. The upper cover 200 includes a terminal portion on the protruding portion for connection to an external circuit. The upper cover 200 may also include one or more outlets for venting gas around the terminal portion.

[0102] The lower cover 310 is positioned below the upper cover 200. The lower cover 310 includes one or more holes 340 formed in at least one portion.

[0103] The vent 320 is positioned between the upper cover 200 and the lower cover 310. The vent 320 includes a downwardly projecting protrusion that connects to the sub-plate. That is, the protrusion is formed to project in the opposite direction to the upper cover 200. In addition, the vent 320 includes at least one recess positioned around the protrusion.

[0104] When the secondary battery 100 is overcharged and / or malfunctions, gas may be generated within it. In this case, the internal pressure of the housing 50 increases due to the gas. Therefore, the protrusion may deform upwards due to the pressure and may separate from the sub-plate. Furthermore, the vent 320 may be cut along the notch. When the vent 320 is cut off, the gas in the housing is released to the outside of the housing 50. Therefore, the cover assembly 300 according to an embodiment of the present invention can prevent the secondary battery 100 from exploding.

[0105] An insulator 330 is positioned between the lower cover 310 and the vent 320. For example, the insulator 330 may be positioned at the edge between the lower cover 310 and the vent 320, and for example, the insulator 330 may be formed as a ring around the edge between the lower cover 310 and the vent 320. In this way, the insulator 330 forms a gap between the lower cover 310 and the vent 320.

[0106] Insulator 330 electrically insulates the lower cover 310 and the vent 320. For example, insulator 330 may comprise a resin material such as polyethylene (PE), polypropylene (PP), or polyethylene terephthalate (PET).

[0107] For example, when the internal temperature of the housing 50 rises, the insulator 330 may melt. In this case, the gas generated in the housing 50 is introduced through the gap between the lower cover 310 and the vent 320. The introduced gas increases the pressure in the space between the lower cover 310 and the vent 320, causing the vent 320 to rupture due to the pressure. The gas can then be released to the outside through the ruptured vent 320. Therefore, the gas generated in the housing 50 is released to the outside of the housing 50.

[0108] A sub-plate (not shown) is positioned below the lower cover 310. The sub-plate can be fixed to the lower surface of the lower cover 310 to block the hole 340 formed in the lower cover 310. In addition, the sub-plate can fix the protrusion of the vent 320.

[0109] The cover assembly 300 can be electrically connected to an electrode extending from the electrode assembly 40 (e.g., see reference 400). Figure 1 and Figure 2 (Description of the negative or positive electrode).

[0110] With this construction, the cover assembly 300 according to an embodiment of the present invention can prevent the secondary battery 100 from exploding.

[0111] Meanwhile, in at least a portion of the cover assembly 300, for example, the upper cover 200 is made of cold-rolled steel sheet including iron (Fe) and / or formed of steel sheet plated with nickel (Ni). However, in this case, problems may arise in terms of thickness uniformity and weldability due to the nickel. Furthermore, in this case, there is a problem that rust may occur due to iron during long-term use.

[0112] The top cover 200, which is used to solve the above problems, will be described in detail below.

[0113] Figure 4 This is a top view of the top cover according to an embodiment of the present invention.

[0114] As referenced above Figures 1 to 3 As described, a secondary battery 100 according to an embodiment of the present invention is sealed by a cover assembly 300 according to an embodiment of the present invention. Here, the cover assembly 300 includes an upper cover 200.

[0115] According to one embodiment of the present invention, the top cover 200 comprises an aluminum alloy, wherein aluminum is its main component. In this way, the top cover 200 does not rust even after prolonged use. The composition of the top cover 200 will be described in more detail below.

[0116] For example, the cover 200 comprises an aluminum (Al) alloy containing magnesium. Here, for example, the magnesium includes environmentally friendly magnesium (Eco-Mg). In this way, the cover 200 can prevent the formation of oxides due to magnesium.

[0117] Here, when the magnesium content is less than 5 wt%, the strength and / or elongation of the aluminum alloy decreases. In this case, there is a problem of cracking when the aluminum alloy is machined into the shape of the cover 200. Therefore, the cover 200 according to one embodiment of the present invention may include magnesium (Mg) in an amount of 5 wt% or greater. For example, the cover 200 according to one embodiment of the present invention may include magnesium (Mg) in an amount of about 5 wt% or greater.

[0118] Furthermore, when the magnesium content is 10 wt% or higher, the strength of the aluminum alloy increases excessively. In this case, there is a problem that the aluminum alloy cannot be machined into the shape of the top cover 200.

[0119] The top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 10.0 wt%. Although an example of the top cover 200 including magnesium in an amount of 5.0 wt% or more and less than 10.0 wt% is described below for ease of description, the composition of the top cover 200 according to one embodiment of the present invention is not limited thereto. For example, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 9.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 8.5 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 8.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.8 wt% or more and less than 10.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.8 wt% or more and less than 9.5 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.8 wt% or more and less than 9.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 6.8 wt% or more and less than 10.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 6.8 wt% or more and less than 9.5 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 6.8 wt% or more and less than 9.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 7.4 wt% or more and less than 10.0 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.8 wt% or more and less than 7.4 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 6.8 wt% or more and less than 7.4 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.8 wt% or more and less than 6.4 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 7.4 wt%. Optionally, the top cover 200 according to one embodiment of the present invention may include magnesium in an amount of 5.0 wt% or more and less than 6.4 wt%.

[0120] In addition, the top cover 200 may also include additives. For example, the additive may be at least one of Si, Fe, Cu, Mn, Cr and Zn, and each of these may be added in an amount of 1 wt% or less. In one embodiment, the weight ratio between Fe and Mg may be in the range of 1:10 to 1:20 (e.g., including 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19 and 1:20), for example, in the range of 1:12.5 to 1:18.5 (e.g., including 1:12.5, 1:13, 1:13.5, 1:14, 1:14.5, 1:15, 1:15.5, 1:16, 1:16.5, 1:17, 1:17.5, 1:18 and 1:18.5). Optionally, in one embodiment, for example, the weight ratio of Si to Mg can be in the range of 1:20 to 1:30 (e.g., including 1:20, 1:21, 1:22, 1:23, 1:24, 1:25, 1:26, 1:27, 1:28, 1:29, and 1:30). In this way, the cover 200 can be formed from a high-strength alloy using a specific heat treatment. Furthermore, the cover 200 can have good weldability and / or excellent wear resistance. Here, for example, the amount of components included in the cover 200 can be analyzed under the following conditions.

[0121] 1) Equipment: ED-XRF (Shimadzu) 2) Probe particle size: 1mm to 10mm 3) Detection time: 60 seconds / 2ch 4) Measurement environment: He As can be seen, by having the above components, the top cover 200 according to an embodiment of the present invention has appropriate strength and elongation.

[0122] Meanwhile, for example, the cover 200 is manufactured from a sheet comprising an aluminum alloy by undergoing rolling, cutting, and forming processes. Here, as described above, the sheet comprises an aluminum alloy containing magnesium in an amount of 5 wt% or greater. Alternatively, for example, the sheet comprises an aluminum alloy containing magnesium in an amount of about 5 wt% or greater and less than about 10 wt%.

[0123] The top cover 200 is manufactured by performing a pressing task on a plate via a mold. Here, the mold may have a shape corresponding to the shape of the top cover 200.

[0124] In this way, such as Figure 4As shown, the top cover 200 includes a central portion 210 and an edge portion 230. The central portion 210 is formed at the center of the top cover 200. The edge portion 230 is formed along the edge of the top cover 200. Here, the central portion 210 is formed to protrude beyond the edge portion 230. For example, the central portion 210 is a portion formed to protrude upward from the top cover 200 (see...). Figure 3 ).

[0125] Furthermore, the top cover 200 may also include a side portion 220 connecting the center portion 210 and the edge portion 230. That is, for example, the edge portion 230 may be formed in an annular shape. When viewed from the side, the top cover 200 may be formed in a hat shape due to the side portion 220 (see...). Figure 5 ).

[0126] The side portion 220 can vertically connect the center portion 210 and the edge portion 230. Alternatively, the side portion 220 can obliquely connect the center portion 210 and the edge portion 230. In this case, the side portion 220 is formed in the direction extending from the center portion 210 and is connected to one side of the edge portion 230.

[0127] Simultaneously, the side portion 220 can connect the entire circumference of the center portion 210 and the entire inner circumference of the edge portion 230. However, as... Figure 4 As shown, the side portion 220 can connect a portion of the circumference of the center portion 210 and a portion of the circumference of the edge portion 230. That is, by not connecting the center portion 210 and the edge portion 230, the side portion 220 can form a reference. Figure 3 The described outlet 240 serves as a channel through which the cover 200 discharges gases generated by the secondary battery 100 to the outside of the housing.

[0128] For example, the outlets 240 are all formed with a first angle α. The first angle α is the angle between a straight line connecting the center O of the upper cover 200 and one side end of the outlet 240 in a direction from the center O of the upper cover 200 toward the outer periphery of the upper cover 200, and a straight line connecting the center O of the upper cover 200 and the other side end of the outlet 240. For example, the range of the first angle α is 70° to 90°. Alternatively, for example, the first angle α is in the range of about 70° to about 90°. For example, the first angle α can be 70°, 71°, 72°, 73°, 74°, 75°, 76°, 77°, 78°, 79°, 80°, 81°, 82°, 83°, 84°, 85°, 86°, 87°, 88°, 89°, or 90°. In this way, by being formed to a sufficient size, the first angle α can facilitate the discharge of gas through the outlet 240 and can provide support such that the center portion 210 and the edge portion 230 are fixed to each other.

[0129] Meanwhile, outlet 240 includes a first outlet 241 and a second outlet 242. The first outlet 241 and the second outlet 242 are formed adjacent to each other. A second angle β is formed between the first outlet 241 and the second outlet 242. The second angle β is the angle between a straight line connecting the center O of the upper cover 200 and the center of the first outlet 241 in a direction from the center O of the upper cover 200 toward the outer periphery of the upper cover 200, and a straight line connecting the center O of the upper cover 200 and the center of the second outlet 242. For example, the second angle β ranges from 90° to 150°. For example, the second angle β is in the range of about 90° to about 150°. For example, the second angle β can be 90°, 95°, 100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, or 150°.

[0130] Here, when the cover 200 includes a plurality of outlets 240, the plurality of outlets 240 may be formed at equal intervals. However, the plurality of outlets 240 may be formed at equal or different intervals. Of course, the plurality of outlets 240 may be formed to have the same or different sizes and / or shapes.

[0131] Utilizing the above composition and / or construction, a cover 200 according to one embodiment of the present invention can provide a cover with excellent formability and appropriate strength, while not causing rust even during long-term use. Additionally, one embodiment of the present invention can provide a cover 200 with excellent weldability and low weight by using an aluminum alloy comprising magnesium.

[0132] Figure 5 This is a cross-sectional view of the top cover according to an embodiment of the present invention.

[0133] As referenced above Figure 3 and Figure 4 As described, the top cover 200 according to one embodiment of the present invention has a central portion 210 formed to protrude beyond the edge portion 230. For example, due to the protrusion of the central portion 210, the edge portion 230 and the central portion 210 can be formed to have a height ratio in the range of 6:10 to 6:23. For example, due to the protrusion of the central portion 210, the edge portion 230 and the central portion 210 can be formed to have a height ratio in the range of about 6:10 to about 6:23. This is because, for example, when the height ratio is less than 6:10, the vent may not be able to function, and when the height ratio is greater than 6:23, cracks may form.

[0134] Here, the height h1 of the edge portion 230 can be equal to the thickness of the edge portion 230. Furthermore, the height h1 of the edge portion 230 can be equal to the thickness of every part of the entire cover 200. That is, all areas of the cover 200 can be formed to have the same thickness. However, this is merely an example; some or all areas of the cover 200 can have different thicknesses.

[0135] Here, the height h2 of the center part 210 is the vertical distance between the extension line of the edge part 230 and the extension line of the center part 210, and can be equal to the total height of the top cover 200.

[0136] For example, when the height h1 of the edge portion 230 is 0.6 mm, the height h2 of the center portion 210 can be 1.0 mm or greater and 2.3 mm or less. For example, when the height h1 of the edge portion 230 is 0.6 mm, the height h2 of the center portion 210 can be approximately 1.0 mm or greater and approximately 2.3 mm or less. When the height h2 of the center portion 210 is less than approximately 1.0 mm, the vent located below the top cover 200 may be immovable. In this case, the vent may fail to function or may be underfunctional. Alternatively, when the height h2 of the center portion 210 exceeds approximately 2.3 mm, cracks may form in the top cover 200. However, the above values ​​related to height are merely examples.

[0137] For example, the top cover 200 can be formed to have a height that is 1.0% or greater and 4.0% or less of the total height of the secondary battery 100. Alternatively, for example, the top cover 200 can be formed to have a height that is 1.1% or greater and 4.0% or less of the total height of the secondary battery 100. Alternatively, for example, the top cover 200 can be formed to have a height that is 1.2% or greater and 4.0% or less of the total height of the secondary battery 100. Alternatively, for example, the top cover 200 can be formed to have a height that is 1.0% or greater and 3.9% or less of the total height of the secondary battery 100. Alternatively, for example, the top cover 200 can be formed to have a height that is 1.0% or greater and 3.8% or less of the total height of the secondary battery 100. Alternatively, for example, the top cover 200 can be formed to have a height that is 1.0% or greater and 3.7% or less of the total height of the secondary battery 100. Optionally, for example, the top cover 200 may be formed to have a height that is 1.1% or greater and 3.9% or less of the total height of the secondary battery 100. Optionally, for example, the top cover 200 may be formed to have a height that is 1.2% or greater and 3.8% or less of the total height of the secondary battery 100. Here, the height of the top cover 200 is the height h2 of the center portion 210.

[0138] By using an aluminum alloy comprising 5 wt% or more magnesium, the cover 200 according to one embodiment of the invention can be manufactured into various shapes as needed (such as reference). Figure 5 (Described shape) without forming cracks.

[0139] Figure 6 It is a graph used to describe the effect of the cover according to an embodiment of the present invention.

[0140] exist Figure 6 In the examples, the upper cover 200 and the cover assembly 300 including the upper cover 200 are shown according to an embodiment of the present invention (e.g., including Example 1 described below). Furthermore, in Figure 6 In the comparative example, a cover made of SPCE material is shown. SPCE is cold-rolled steel and includes iron (Fe). Here, the cover according to the example and the comparative example is manufactured with the same dimensions (the cover has a thickness tolerance of ±0.05 mm). Furthermore, the cover assembly according to the example and the comparative example is manufactured with the same dimensions (the cover has a thickness tolerance of ±0.05 mm).

[0141] Figure 6 The values ​​shown represent the average of those obtained by measuring the weight of each lid ten times. From Figure 6 As shown in the graph, the weight of the top cover 200 according to an embodiment of the present invention is reduced to approximately 0.35g, compared to approximately 1.0g for a conventional top cover. That is, compared to a conventional top cover, the top cover 200 according to an embodiment of the present invention has the effect of reducing weight by approximately 65%.

[0142] Figure 6 The values ​​shown represent the average of those obtained by measuring the weight of each cover assembly ten times. From Figure 6 As shown in the graph, the weight of the cap assembly 300 according to an embodiment of the present invention is reduced to approximately 0.9g, compared to approximately 1.5g as a conventional cap assembly. That is, compared to a conventional cap assembly, the cap assembly 300 according to an embodiment of the present invention achieves a weight reduction of approximately 42%.

[0143] In this way, the cover 200 according to one embodiment of the present invention may have a weight of 50% or less of the cover assembly 300. That is, the cover 200 may be formed to have a weight of 50% or less of the cover assembly 300. Optionally, the cover 200 may be formed to have a weight of 45% or less of the cover assembly 300. Optionally, the cover 200 may be formed to have a weight of 40% or less of the cover assembly 300.

[0144] In this way, by using aluminum alloy, one embodiment of the present invention can provide a cover 200 with reduced weight compared to a conventional cover made of iron. Furthermore, one embodiment of the present invention can provide a cover assembly 300 including the cover 200 with reduced weight and / or a secondary battery 100.

[0145] Meanwhile, according to one embodiment of the present invention, the top cover 200 can have a strength of 15 kgf / mm². 2 Or greater compressive strength. Therefore, the cover 200 can allow less crack formation in the cover compared to using conventional aluminum. Furthermore, the cover 200 can meet the compressive strength required by conventional SPCE. In this way, by including an aluminum alloy containing 5 wt% or more magnesium, one embodiment of the invention can provide a cover 200 with higher compressive strength than a cover made using conventional aluminum alloys.

[0146] The following will describe the above references Figures 1 to 6 Examples of the application of the described top cover 200, cover assembly 300, and / or secondary battery 100 to electronic devices or for the purpose of referring to the above-described examples. Figures 1 to 6 Examples of the application of the already described top cover 200, cover assembly 300 and / or secondary battery 100 to electronic devices.

[0147] Figure 7 This is a schematic cross-sectional view of a secondary battery module according to an embodiment of the present invention.

[0148] like Figure 7 As shown, the secondary battery module 1000 according to the present invention includes a plurality of secondary batteries 100 and a housing 1100 for accommodating the plurality of secondary batteries 100. Meanwhile, although the secondary battery module 1000 in... Figure 7 The diagram shows eight secondary batteries 100, but this is merely for ease of description, and the number of secondary batteries 100 included in the secondary battery module 1000 according to the present invention is not limited thereto. The secondary battery module 1000 may include two or more secondary batteries 100. The secondary batteries 100 are as described above. Figures 1 to 6 The secondary battery 100 described is the same as or similar to the one described.

[0149] The housing 1100 includes a body into which one side of each of the plurality of secondary batteries 100 is inserted. The body allows the plurality of secondary batteries 100 to be arranged in one direction. For this purpose, the body may include a plurality of holes into which one side of one of the plurality of secondary batteries 100 is inserted. The number of holes is equal to or greater than the number of secondary batteries 100. Here, for example, the plurality of holes may be formed in a simple cubic (SC) form, such as... Figure 7 As shown. Alternatively, for example, with Figure 7Unlike other structures, multiple holes can be formed in body-centered cubic (BCC), face-centered cubic (FCC), or hexagonal close-packed (HCP) configurations. In other words, multiple holes can be arranged in various structural configurations. Furthermore, multiple holes can have different sizes or shapes, and can have cross-sections with circular, polygonal, or other shapes.

[0150] Meanwhile, the housing 1100 may also include a plurality of retaining parts connected to the main body and extending in a direction from the main body toward the assembly of the secondary battery 100.

[0151] The secondary battery module 1000 may further include connecting members (not shown) that electrically connect multiple secondary batteries 100. The connecting members include an upper connecting member and a lower connecting member. The upper connecting member connects to the upper portion of at least some of the multiple secondary batteries 100. For example, the upper connecting member is electrically connected to one side terminal of the multiple secondary batteries 100. For example, the one-side terminal is a terminal of the same polarity. The lower connecting member connects to the lower portion of at least some of the multiple secondary batteries 100. For example, the lower connecting member is electrically connected to another side terminal of the multiple secondary batteries 100. For example, the other side terminal is a terminal of the same polarity but with a different polarity than the one-side terminal.

[0152] The secondary battery module 1000 may also include a protection circuit (not shown) for protecting multiple secondary batteries 100. Furthermore, the secondary battery module 1000 may also include wiring that electrically connects the connecting components and the protection circuit.

[0153] In this way, one embodiment of the invention can provide a secondary battery module 1000 with improved stability by including a secondary battery 100 having an upper cover 200 with improved solderability and / or reduced weight, a cover assembly 300, and / or at least one of these.

[0154] Figure 8 This is a view showing a secondary battery pack according to an embodiment of the present invention.

[0155] Figure 9 This is a view showing a secondary battery pack according to an embodiment of the present invention.

[0156] A secondary battery pack 2000 according to an embodiment of the present invention includes components in which the various secondary batteries are electrically connected and a housing housing the components. In the accompanying drawings, for ease of illustration, components for the electrical connection of the secondary batteries (such as busbars, cooling units, and external terminals) are omitted from the illustration.

[0157] Specifically, the secondary battery pack 2000 may include multiple secondary battery modules 1000 (e.g., including referenced...) Figure 7The description includes a secondary battery module 1000 and a housing 2100 for housing the secondary battery module 1000. For example, the housing 2100 may include a first housing 2101 and a second housing 2102, which are joined together in a direction facing each other, with multiple secondary battery modules 1000 disposed between the first housing 2101 and the second housing 2102. The multiple secondary battery modules 1000 can be electrically connected to each other using a busbar 2200, and the desired electrical output can be obtained by electrically connecting the multiple secondary battery modules 1000 in series / parallel or a mixture of series and parallel connections.

[0158] In this way, one embodiment of the present invention can be achieved by including the above-mentioned references. Figures 3 to 6 The secondary battery 100 and / or secondary battery module 1000 described in the present invention, with the cover 200 and / or cover assembly 300, provide a secondary battery pack 2000 with improved stability and reduced weight.

[0159] Figure 10 This is a view showing a vehicle body and vehicle body components according to an embodiment of the present invention.

[0160] Reference above Figure 8 and Figure 9 The secondary battery pack 2000 described according to one embodiment of the present invention can be installed in a vehicle 3000. For example, the vehicle 3000 can be an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle can be a four-wheeled vehicle or a two-wheeled vehicle.

[0161] like Figure 10 As shown, a vehicle 3000 according to an embodiment of the present invention includes a secondary battery module 1000 and / or a secondary battery pack 2000 including the secondary battery module 1000 according to an embodiment of the present invention. The vehicle 3000 operates by receiving power from the secondary battery module 1000 and / or the secondary battery pack 2000 including the secondary battery module 1000 according to an embodiment of the present invention.

[0162] In this way, one embodiment of the present invention can be achieved by including the above-mentioned references. Figures 3 to 6 The secondary battery 100, secondary battery module 1000 and / or secondary battery pack 2000 described in the present invention, along with the cover 200 and / or cover assembly 300, provide a vehicle 3000 with improved stability and reduced weight.

[0163] In the following sections, comparative examples and examples according to the present invention will be described. However, the following examples are merely one embodiment of the present invention, and the present invention is not limited to the following examples.

[0164] Table 1 below shows the tensile strength (kgf / mm) of a top cover 200 according to an embodiment of the present invention and a top cover corresponding to a comparative example. 2 ) and elongation (%).

[0165] [Table 1]

[0166] 1) Compositions of Comparative Examples 1 to 4 and Examples 1 to 3 (1) Comparison Example 1: Al alloy (2) Comparative Example 2: Al alloy containing less than 2.5 wt% Mg (3) Comparative Example 3: Al alloy containing 2.5 wt% or more and less than 4.4 wt% of Mg (4) Comparative Example 4: Al alloy containing 4.4 wt% or more and less than 5.0 wt% Mg (5) Example 1: Al alloy containing 5.8 wt% or more and less than 6.4 wt% of Mg (6) Example 2: Al alloy containing 6.8 wt% or more and less than 7.4 wt% of Mg (7) Example 3: Al alloy containing 7.4 wt% or more of Mg.

[0167] Here, the Al alloys of Comparative Examples 1 to 4 and Examples 1 to 3 all include at least one of Si, Fe, Cu, Mn, Cr, and Zn, and include Al, in amounts of 1 wt% or less. Here, the Al alloy of Comparative Example 1 is the one mentioned above. Figure 6 The SPCE material is described and applied to a standard top cover.

[0168] 2) Manufacturing processes of Comparative Examples 1 to 4 and Examples 1 to 3 When aluminum is molten into ingot form, the components listed in 1) are added, and a billet is manufactured through melting, casting, homogenization, and cutting processes. The billet is then subjected to heating, extrusion, straightening, and cutting processes. Here, the billet is cut to give each billet a height of 2.30 mm, a thickness of 0.60 mm, a center diameter of 12.20 mm, and an edge diameter of 18.52 mm. Here, each value has an error range of ±0.5 mm. The cut billet is then used to manufacture the top cover by heat treatment at 400°C for 2 hours.

[0169] 3) Method for measuring the tensile strength and elongation of Comparative Examples 1 to 4 and Examples 1 to 3 The tensile strength and elongation of the cover manufactured by 2) were measured under the following conditions. Here, the tensile strength was measured using the maximum compressive force (kgf), and the elongation was measured using the maximum force distance (mm).

[0170] (1) Test distance (press amount): 1.2mm (2) Test speed (pressing speed): 10.00 mm / min (3) Press pin diameter (Pi): 3.7mm As can be seen from [Table 1], the tensile strength of each of Examples 1 and 2 is similar to that of Comparative Example 1. Furthermore, the tensile strength of Example 3 is higher than that of Comparative Example 1.

[0171] Furthermore, as can be seen from [Table 1], the tensile strength of each of Examples 1 to 3 is higher than or equal to the tensile strength of each of Comparative Examples 2 to 4. In addition, the elongation of each of Examples 1 to 3 is higher than the elongation of each of Comparative Examples 2 to 4.

[0172] In other words, by having tensile strength that allows the Al alloy to be used as a cover, the Al alloy of each of Examples 1 to 3 can be used as a conventional Al alloy compared to Example 1. Meanwhile, by including magnesium (Mg), the Al alloy of each of Examples 1 to 3 can provide a cover that reduces rust, is lightweight, and has improved weldability. Furthermore, by including an appropriate amount of magnesium (Mg), the Al alloy of each of Examples 1 to 3 can have an elongation that allows for shaping.

[0173] The present invention has been described above using only some embodiments and accompanying drawings, but the present invention is not limited thereto. Of course, those skilled in the art can make various modifications and changes within the scope of the technical spirit of the present invention and within the scope equivalent to the appended claims.

[0174] [Industrial Applicability] The embodiments of the present invention have industrial applicability.

Claims

1. A secondary battery, the secondary battery comprising: case; Electrode assembly, housed within the housing; as well as A cover assembly that blocks the opening of the housing and seals the electrode assembly. The cover assembly includes an upper cover, which comprises aluminum and 5 wt% or more magnesium as the main components of the upper cover.

2. The secondary battery according to claim 1, wherein, The top cover includes at least one of Si, Fe, Cu, Mn, Cr and Zn in amounts of 1 wt% or less.

3. The secondary battery according to claim 1, wherein, The top cover includes: An edge portion is formed along the edge of the upper cover; and The central portion is formed at the center of the upper cover and is formed to protrude beyond the edge portion.

4. The secondary battery according to claim 3, wherein, The edge portion and the center portion have a height ratio in the range of 6:10 to 6:

23.

5. The secondary battery according to claim 1, wherein, The top cover has a strength of 15 kgf / mm². 2 Or greater compressive strength.

6. The secondary battery according to claim 1, wherein, The top cover has an elongation of 30% or higher.

7. The secondary battery according to claim 1, wherein, The cover assembly includes: The lower cover is positioned below the upper cover; An exhaust port, located between the upper and lower covers, deforms or ruptures when the internal pressure of the housing exceeds a predetermined pressure; and An insulator is positioned between the lower cover and the vent, forming a gap between the lower cover and the vent.

8. The secondary battery according to claim 1, wherein, The shell comprises a cylindrical container.

9. The secondary battery according to claim 1, wherein, The top cover is formed to have a weight of 50% or less as part of the weight of the cover assembly.

10. The secondary battery according to claim 1, wherein, The top cover is formed to have a height that is 1.0% or greater and 4.0% or less relative to the height of the secondary battery.

11. A secondary battery module, the secondary battery module comprising: Multiple secondary batteries; as well as The casing houses the plurality of secondary batteries. At least some of the plurality of secondary batteries include: a housing; an electrode assembly housed in the housing; and a cover assembly that blocks the opening of the housing and seals the electrode assembly, wherein the cover assembly includes an upper cover comprising aluminum as the main component of the upper cover and magnesium in an amount of 5 wt% or greater.

12. The secondary battery module according to claim 11, wherein, The top cover includes at least one of Si, Fe, Cu, Mn, Cr and Zn in amounts of 1 wt% or less.

13. The secondary battery module according to claim 11, wherein, The top cover includes: An edge portion is formed along the edge of the upper cover; and The central portion is formed at the center of the upper cover and is formed to protrude beyond the edge portion.

14. The secondary battery module according to claim 13, wherein, The edge portion and the center portion have a height ratio in the range of 6:10 to 6:

23.

15. The secondary battery module according to claim 11, wherein, The top cover has a strength of 15 kgf / mm². 2 Or greater compressive strength.

16. The secondary battery module according to claim 11, wherein, The top cover has an elongation of 30% or higher.

17. The secondary battery module according to claim 11, wherein: The housing includes: a body, into which one side of each of the plurality of secondary batteries is inserted; and The secondary battery module further includes: an upper connecting member electrically connected to one side terminal of the plurality of secondary batteries; a lower connecting member electrically connected to the other side terminal of the plurality of secondary batteries; and a protection circuit for protecting the plurality of secondary batteries.

18. The secondary battery module according to claim 11, wherein, The top cover is formed to have a weight of 50% or less as part of the weight of the cover assembly.

19. The secondary battery module according to claim 11, wherein, The top cover is formed to have a height that is 1.0% or greater and 4.0% or less relative to the height of the secondary battery.

20. A secondary battery pack, the battery pack comprising: The secondary battery module according to any one of claims 11 to 19; as well as A housing is provided to accommodate the secondary battery modules, wherein the secondary battery modules are configured as multiple secondary battery modules.

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