Secondary battery module

Abstract

The present disclosure relates to a secondary battery module, and aims to provide a secondary battery module capable of maintaining a physically stable structure even when a secondary battery is deformed. The secondary battery module includes: a plurality of secondary batteries arranged in a first direction; and a partition member located in a gap between two adjacent secondary batteries among the plurality of secondary batteries. The partition member has a variable length at least in the first direction in response to an electrical signal applied to the partition member.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2024-0138093, filed on October 11, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to a secondary battery module. Background Technology

[0004] Unlike primary batteries, which cannot be recharged, secondary batteries are batteries that can be recharged and discharged. Low-capacity secondary batteries can be used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders. High-capacity secondary batteries are widely used as power sources and energy storage batteries to drive motors in hybrid or electric vehicles. A secondary battery includes an electrode assembly containing positive and negative electrodes, a housing of the electrode assembly, and electrode terminals connected to the electrode assembly.

[0005] With technological advancements, there is a need for high-capacity rechargeable batteries. Accordingly, multiple rechargeable batteries can be electrically connected and used together. For example, rechargeable batteries can be used in electronic devices in the form of battery modules comprising multiple rechargeable batteries and / or battery packs comprising multiple rechargeable battery modules. Rechargeable battery packs are also configured with multiple rechargeable batteries. Therefore, rechargeable batteries can be used together in electronic devices requiring high power and / or high capacity, such as electric vehicles.

[0006] A secondary battery module or secondary battery pack has a plurality of secondary batteries arranged in at least one direction within a housing. The secondary batteries may be arranged adjacent to each other or spaced apart by a predetermined gap.

[0007] The information disclosed above is intended only to enhance understanding of the background of this disclosure and may therefore include information that does not constitute related technology. Summary of the Invention

[0008] This disclosure aims to provide a secondary battery module that can maintain a physically stable structure even when the secondary battery is subjected to deformation.

[0009] This disclosure also aims to provide a secondary battery module capable of absorbing the extension of a secondary battery to prevent damage to the module structure.

[0010] However, the problems to be solved by this disclosure are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

[0011] According to one aspect of this disclosure, a secondary battery module is provided, comprising: a plurality of secondary batteries arranged along a first direction; and a separating member located in the gap between two adjacent secondary batteries among the plurality of secondary batteries, the separating member having a variable length at least in the first direction in response to an electrical signal applied to the separating member.

[0012] According to one aspect of the embodiment, the length of the separating member may be variable, at least in the first direction, depending on the magnitude of the voltage applied to the separating member. For example, the separating member may include: one or more electrically variable elements, each having a length that is variable at least in the first direction, depending on the magnitude of the voltage; and a pair of electrode members configured to apply the voltage to the electrically variable elements.

[0013] In this configuration, the electrically variable element can be configured to change shape according to the magnitude of the voltage, and the pair of electrode members can be located on the outer side of each of the one or more electrically variable elements in the first direction. As an example, the electrically variable element can be formed of a piezoelectric material or an electroactive polymer material. As another example, the pair of electrode members can each be formed of a metallic material having a melting point higher than that of the material of the casing of each of the plurality of secondary batteries. As yet another example, the separating member can further include a pair of insulating members located on the outer side of the pair of electrode members in the first direction. The pair of insulating members can each be formed of one or more materials selected from alumina, mica, and silica gel.

[0014] According to another aspect of the embodiment, the secondary battery module may further include a sensor configured to detect whether at least one of the plurality of secondary batteries is swollen, wherein an electrical signal may be applied to the separating member based on the detection result of the sensor.

[0015] As an example, the secondary battery module may further include a power source configured to generate the electrical signal and apply the electrical signal to the separator member, wherein the sensor is configured to estimate the degree of expansion based on at least one of the state of charge of at least one of the plurality of secondary batteries and the number of charge-discharge cycles, the power source is configured to generate the electrical signal having an amplitude corresponding to the estimated degree of expansion, and the length of the separator member may be variable in the first direction depending on the amplitude of the electrical signal applied to the separator member.

[0016] As another example, the secondary battery module may further include a power source configured to generate the electrical signal and apply the electrical signal to the separator member, wherein the sensor is configured to determine the degree of expansion based on the size of at least one of the plurality of secondary batteries in the first direction, the power source is configured to generate the electrical signal having an amplitude corresponding to the determined degree of expansion, and the length of the separator member is variable in the first direction according to the amplitude of the electrical signal applied to the separator member.

[0017] According to another aspect of this disclosure, a secondary battery module is provided, comprising: a plurality of secondary batteries arranged along a first direction; and a separating member located in a gap between two adjacent secondary batteries among the plurality of secondary batteries, the separating member having a variable thickness in response to an electrical signal applied to the separating member, wherein the separating member may include: an electrically variable element configured to change size at least in the first direction according to the amplitude of the electrical signal; a pair of electrode plates located on the outer side of the electrically variable element in the first direction and configured to apply the electrical signal to the electrically variable element; and a pair of insulating plates located on the outer side of the pair of electrode plates in the first direction.

[0018] According to one aspect of the embodiments, the electrically variable element may include one or more of a piezoelectric element and an electroactive polymer element.

[0019] According to another aspect of the embodiment, the electrically variable element may be a sheet having a thickness in the first direction.

[0020] According to another aspect of the embodiment, the electrically variable element may include a plurality of electrically variable elements, and the electrically variable elements may be spaced apart from each other in a plane parallel to the electrode plate.

[0021] According to another aspect of the embodiment, the pair of electrode plates may each be formed of a metallic material having a melting point higher than that of the material of the casing of each of the plurality of secondary batteries.

[0022] According to another aspect of the embodiment, the pair of insulating plates may each be formed of one or more materials selected from alumina, mica, and silica gel.

[0023] According to another aspect of the embodiment, the secondary battery module may further include a sensor configured to detect whether at least one of the plurality of secondary batteries is swollen, wherein an electrical signal may be applied to the separating member based on the detection result of the sensor.

[0024] As an example, the secondary battery module may further include a power source configured to generate the electrical signal and apply the electrical signal to the pair of electrode plates, wherein the sensor is configured to estimate the degree of expansion based on at least one of the state of charge of at least one of the plurality of secondary batteries and the number of charge-discharge cycles, the power source is configured to generate the electrical signal having an amplitude corresponding to the estimated degree of expansion, and the thickness of the electrically variable element is variable in the first direction according to the amplitude of the electrical signal applied to the electrically variable element.

[0025] As another example, the secondary battery module may further include a power source configured to generate the electrical signal and apply the electrical signal to the pair of electrode plates, wherein the sensor is configured to determine the degree of expansion based on the size of at least one of the plurality of secondary batteries in the first direction, the power source may be configured to generate the electrical signal having an amplitude corresponding to the determined degree of expansion, and the thickness of the electrically variable element is variable in the first direction according to the amplitude of the electrical signal applied to the electrically variable element. Attached Figure Description

[0026] The accompanying drawings are intended to illustrate exemplary embodiments of the present disclosure, and the spirit of the disclosure will be more clearly understood from the drawings and the following description of the disclosure, in which:

[0027] Figure 1 This is a perspective view of a secondary battery module according to an embodiment of the present disclosure;

[0028] Figure 2 yes Figure 1 A perspective view of the secondary battery included in the secondary battery module;

[0029] Figure 3 It is intercepted along the YZ plane. Figure 2 A cross-sectional view of a secondary battery;

[0030] Figure 4A yes Figure 1 A perspective view of the partition components included in the secondary battery module;

[0031] Figure 4B yes Figure 4A The main view of the dividing component;

[0032] Figure 5A This is a cross-sectional view of a secondary battery module according to an embodiment, illustrating the state where the secondary battery does not expand; and

[0033] Figure 5BThis is a cross-sectional view of another example of a secondary battery module according to an embodiment, illustrating the state of secondary battery expansion. 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 general or dictionary meanings, and should be interpreted in a manner consistent with the spirit of the invention, based on the inventor's ability to appropriately define concepts and terms. Therefore, the embodiments described herein and the configurations illustrated in the drawings are merely some of the most preferred embodiments and do not represent the full spirit of the invention; and thus, it should be understood that various equivalents and modifications can be made upon filing this application.

[0035] Furthermore, when used in this specification, "comprising" and / or "including" designates the presence of the shape, number, step, operation, component, element, and / or group thereof, and may not exclude the presence or addition of one or more other shapes, numbers, steps, operations, components, elements, and / or groups thereof.

[0036] Furthermore, to aid in understanding the invention, the accompanying drawings may not be shown to scale. Instead, the dimensions of some components may be enlarged. Additionally, the same reference numerals may be assigned to the same components in different embodiments.

[0037] The description of two objects being compared as "identical" can mean that they are "substantially identical." Therefore, the range of expressions "substantially identical" can include cases with what is considered a low degree of deviation (e.g., within 5%). Additionally, the description of a parameter being identical in a certain region can mean that the parameter is identical on average.

[0038] Terms including ordinal numbers such as first and second can be used to describe various components, but of course, components are not limited by these terms. These terms are only used to distinguish one component from another. Unless specifically described as the opposite, the first component can also be the second component.

[0039] Throughout this instruction manual, unless otherwise specifically described, each component may be provided in the singular or plural.

[0040] Any arrangement on or above (below) the component’s “upper (or lower) portion” can mean not only that any arrangement can be configured to contact the upper (or lower) surface of the component, but also that another arrangement can be between the component and any arrangement on (or below) the component.

[0041] Additionally, when describing a component as being “connected”, “linked” to, or “close to” another component, these components may be directly connected or close to each other, but it should be understood that another component may be “between” these components, or these components may be “connected,” “linked,” or “close to” another component.

[0042] As used herein, the term “and / or” includes any one and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of “may” means “one or more embodiments of this disclosure.” When following a list of elements, the terms “one or more of…” and “at least one of…” modify the entire list of elements, not individual elements within the list.

[0043] Throughout this specification, unless otherwise stated, the expression "A and / or B" means A, B, or A and B. Unless otherwise stated, the expression "C to D" means C and above and D and below.

[0044] When phrases 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” are used to indicate a list of elements A, B and C, the phrase may refer to any one of A, B and C and all suitable combinations or subsets of them, such as A, B, C, A and B, A and C, B and C, or A and B and C.

[0045] As used herein, the term “use” may be considered synonymous with the term “utilize”. As used herein, the terms “substantially,” “approximately,” and similar terms are used as approximate terms and not as terms of degree, and are intended to take into account the inherent variations in measurements or calculations that would be recognized by one of ordinary skill 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 sections, 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. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or section discussed below may be referred to as the second element, component, region, layer, or section.

[0047] For ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” and “up” are used herein to describe the relationship between one element or feature illustrated in the accompanying drawings and other elements or features. It will be understood that spatial relative terms are intended to cover different orientations of the device in use or operation, other than the orientation depicted in the figures. For example, when the device in the figures is flipped, an element described as “below” or “under” other elements will then be oriented as “above” or “upon” other elements. Therefore, the term “below” can encompass both above and below orientations.

[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 perspective view of a secondary battery module according to an embodiment of the present disclosure. Reference Figure 1 The secondary battery module 1 includes a secondary battery 100, a module housing 200, a busbar 300, and a separator 400.

[0050] Multiple secondary batteries 100 can be included in the module housing 200. The multiple secondary batteries 100 can be arranged in a row along the length or width direction of the module housing 200. Figure 1 The example shown illustrates eight secondary batteries 100 arranged along the length direction (X-axis direction) of the module housing 200. However, the arrangement of multiple secondary batteries 100 is not limited to this and can be varied. For example, multiple secondary batteries 100 can be arranged along the width direction (Y-axis direction) of the module housing 200. Multiple secondary batteries 100 arranged in a row along the X-axis direction can be arranged side by side in the Y-axis direction to form two or more rows, or multiple secondary batteries 100 arranged in a row along the Y-axis direction can be arranged side by side in the X-axis direction to form two or more rows. Alternatively, multiple secondary batteries 100 arranged in a row along the X-axis and / or Y-axis directions can be stacked and arranged in two or more layers in the Z-axis direction within the module housing 200.

[0051] According to this embodiment, multiple secondary batteries 100 are arranged to be spaced apart from each other by a predetermined distance. That is, there is a predetermined gap between adjacent secondary batteries 100. A separator 400 is disposed in the gap. In other words, in the secondary battery module 1 according to this embodiment, the separator 400 is disposed in the gap between two secondary batteries 100 that are spaced apart from each other by a predetermined distance. The separator 400 will be described below.

[0052] Figure 2 yes Figure 1 A perspective view of the configuration of the secondary battery 100 included in the secondary battery module 1. Figure 3 It is intercepted along the YZ plane. Figure 2Cross-sectional view of secondary battery 100. Figure 2 and Figure 3 The secondary battery 100 shown is an example of a lithium-ion secondary battery with a prismatic shape. However, the secondary battery 100 of this disclosure is not limited to... Figure 2 and Figure 3 The secondary battery shown is prismatic, but can be of other types or structures. For example, in this embodiment, the secondary battery 100 is not prismatic, but can be a pouch-type or cylindrical secondary battery.

[0053] refer to Figure 2 and Figure 3 The secondary battery 100 includes: at least one electrode assembly in which an insulating separator 13 is located between and wound together with a positive electrode 11 and a negative electrode 12; a housing 20 for housing the electrode assembly; and a cover assembly 30 connected to an opening in the housing 20. Although not shown in the figures, the positive electrode 11, the negative electrode 12, and the separator 13 constituting the electrode assembly are impregnated with an electrolyte inside the housing 20.

[0054] Positive electrode 11

[0055] The positive electrode 11 for the 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 includes a positive electrode active material and may further include a binder and / or a conductive material. Additionally, the positive electrode 11 may further include additives capable of serving as a sacrificial positive electrode.

[0056] As the positive electrode active material, compounds capable of reversibly inserting and deintercalating lithium (lithiation intercalation compounds) can be used. Specifically, one or more composite oxides of lithium with metals selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0057] The composite oxide can be a lithium transition metal composite oxide, and specific examples may include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof. As an example, compounds represented by any of the following chemical formulas may be used. Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Lia Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b-c Mn b X c O 2-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 Mn 1-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); and Li a FePO4 (0.90≤a≤1.8). In these 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.

[0058] As an example, the positive electrode active material can be a high-nickel-based positive electrode active material, based on 100 mol% of metals other than lithium in a lithium transition metal composite oxide. This high-nickel-based positive electrode active material has a nickel content greater than or equal to 80 mol%, greater than or equal to 85 mol%, greater than or equal to 90 mol%, greater than or equal to 91 mol%, or greater than or equal to 94 mol% and less than or equal to 99 mol%. High-nickel-based positive electrode active materials can achieve high capacity and can be applied to high-capacity and high-density secondary batteries.

[0059] Based on a 100wt% positive electrode active material layer, the amount of positive electrode active material can be 90wt% to 99.5wt%, and based on a 100wt% positive electrode active material layer, the content of each of the binder and conductive material can be 0.5wt% to 5wt%.

[0060] The binder is used to adhere the positive electrode active material particles to each other, and also to adhere the positive electrode active material to the current collector. Representative examples of binders include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene oxide-containing polymers, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, epoxy resin, (meth)acrylate resin, polyester resin, nylon, etc. However, this disclosure is not limited to these examples.

[0061] Conductive materials are used to provide conductivity to electrodes and can be any material that does not cause chemical changes and conducts electricity in a battery. Examples of conductive materials include: carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fibers, carbon nanofibers, carbon nanotubes, etc.; metal-based materials in the form of metal powders or metal fibers, including copper, nickel, aluminum, silver, etc.; conductive polymers, such as polyphenylene derivatives; or mixtures thereof.

[0062] Aluminum can be used as a current collector, but this disclosure is not limited thereto.

[0063] negative electrode 12

[0064] The negative electrode 12 for the secondary battery 100 includes a current collector and a negative electrode active material layer located on the current collector. The negative electrode active material layer includes a negative electrode active material and may further include a binder and / or a conductive material. For example, the negative electrode active material layer may include 90 wt% to 99 wt% of negative electrode active material, 0.5 wt% to 5 wt% of binder, and 0 wt% to 5 wt% of conductive material.

[0065] 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 dedoping lithium, or a transition metal oxide.

[0066] The material capable of reversibly inserting and 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 include graphite, such as natural graphite or artificial graphite in an amorphous, plate-shaped, flaky, spherical, or fibrous form. Examples of amorphous carbon include soft carbon or hard carbon, mesophase pitch carbide products, calcined coke, etc.

[0067] The lithium metal alloy may be 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.

[0068] The Si-based negative electrode active material or the Sn-based negative electrode active material may be used as a material capable of doping and dedoping lithium. The Si-based negative electrode active material may include silicon, a silicon-carbon composite, SiO x (0 < x ≤ 2), a Si-Q alloy, or a combination thereof. In the molecular formula Si-Q, 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. The Sn-based negative electrode active material may include Sn, SiO2, a Sn-based alloy, or a combination thereof.

[0069] 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, the silicon-carbon composite may include secondary particles (cores) in which silicon primary particles are aggregated and an amorphous carbon coating (shell) on the surface of the secondary particles. Amorphous carbon may also be located between the silicon primary particles such that the silicon primary particles are coated with amorphous carbon. The secondary particles may be dispersed in an amorphous carbon matrix.

[0070] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0071] The Si-based negative electrode active material or the Sn-based negative electrode active material may be used by mixing with the carbon-based negative electrode active material.

[0072] A binder is used to adhere the negative electrode active material particles to each other and also to adhere the negative electrode active material to the current collector. As the above binder, a non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof may be used.

[0073] Non-aqueous adhesives may include polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene-propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide-imide, polyimide, or combinations thereof.

[0074] Waterborne adhesives can be selected from styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluoroelastomers, polyethylene oxide, polyvinylpyrrolidone, polyepoxychloropropane, polyphosphazene, poly(meth)acrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0075] When using an aqueous binder as the negative electrode binder, it may further include a cellulose compound capable of imparting viscosity. As a cellulose compound, one or more of carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, or their alkali metal salts may be used in combination. Na, K, or Li may be used as the alkali metal.

[0076] The dry binder is a polymeric material capable of being fibrous, and may be, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, or a combination thereof.

[0077] Conductive materials provide conductivity to electrodes and can be used in batteries as any material that does not cause chemical changes and conducts electricity. Specific examples of conductive materials include: carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fibers, carbon nanofibers, carbon nanotubes, etc.; metal-based materials in the form of metal powders or metal fibers, including copper, nickel, aluminum, silver, etc.; conductive polymers, such as polyphenylene derivatives; or mixtures thereof.

[0078] The negative electrode current collector can be selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, polymer substrate coated with conductive metal, and combinations thereof.

[0079] electrolyte

[0080] The electrolyte used in the secondary battery 100 includes a non-aqueous organic solvent and a lithium salt.

[0081] Non-aqueous organic solvents are used as a medium through which ions participating in the electrochemical reactions of the battery can move.

[0082] Non-aqueous organic solvents can be carbonates, esters, ethers, ketones or alcohols, aprotic solvents or combinations thereof.

[0083] Carbonate solvents can include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), ethyl methyl carbonate (MEC), ethylene carbonate (EC), propylene carbonate (PC), butyl carbonate (BC), etc.

[0084] Ester solvents can include methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate, decanoic acid lactone, mevalonate lactone, caprolactone, etc.

[0085] Ether solvents may include dibutyl ether, tetraethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dimethoxyethane, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, tetrahydrofuran, etc. Ketone solvents may include cyclohexanone, etc. Alcohol solvents may include ethanol, isopropanol, etc., and aprotic solvents may include: nitriles, such as R-CN (where R is a C2-C20 straight-chain, branched, or cyclic hydrocarbon group, and includes double bonds, aromatic rings, or ether bonds), etc.; amides, such as dimethylformamide; dioxolane, such as 1,3-dioxolane and 1,4-dioxolane; sulfolane, etc.

[0086] Non-aqueous organic solvents can be used alone or in combination of two or more.

[0087] In addition, when using carbonate solvents, cyclic carbonates and chain carbonates can be mixed and used, and cyclic carbonates and chain carbonates can be mixed in a volume ratio of 1:1 to 1:9.

[0088] Lithium salts are materials dissolved in organic solvents and used as a source of lithium ions in batteries, enabling secondary batteries to operate fundamentally and improving the movement of lithium ions between the positive and negative electrodes. Representative examples of lithium salts can include those from LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiAlO2, LiAlCl4, LiPO2F2, LiCl, LiI, LiN(SO3C2F5)2, Li(FSO2)2N (lithium bis(fluorosulfonyl)imide, LiFSI), LiC4F9SO3, and LiN(C x F 2x+1 SO2)(C y F 2y+1 One or more of the following: SO2 (where x and y are integers from 1 to 20), lithium trifluoromethane sulfonate, lithium tetrafluoroethane sulfonate, lithium difluorobis(oxalate)phosphate (LiDFOB), and lithium bis(oxalate)borate (LiBOB).

[0089] Diaphragm 13

[0090] Depending on the type of secondary battery 100, a separator 13 may be present between the positive electrode 11 and the negative electrode 12. The separator 13 may comprise a multilayer membrane of polyethylene, polypropylene, polyvinylidene fluoride, or two or more layers thereof. The separator 13 may also comprise a mixed multilayer membrane such as a polyethylene / polypropylene two-layer separator, a polyethylene / polypropylene / polyethylene three-layer separator, or a polyethylene / polypropylene / polypropylene three-layer separator.

[0091] The diaphragm 13 may include a porous substrate and a coating on one or both surfaces of the porous substrate, comprising organic materials, inorganic materials or combinations thereof.

[0092] The porous substrate can be a polymer film formed from polymers selected from polyolefins (such as polyethylene, polypropylene, etc.), polyesters (such as polyethylene terephthalate, polybutylene terephthalate, etc.), polyacetal, polyamide, polyimide, polycarbonate, polyetheretherketone, polyaryletherketone, polyetherimide, polyamideimide, polybenzimidazole, polyethersulfone, polyphenylene ether, cyclic olefin copolymers, polyphenylene sulfide, polyethylene naphthalate, glass fiber, and polytetrafluoroethylene (e.g., Teflon).

[0093] Organic materials may include polymers such as polyvinylidene fluoride or (meth)acrylic acid polymers.

[0094] Inorganic materials 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. However, this disclosure is not limited to these examples.

[0095] Organic and inorganic materials can be present by mixing them in a coating. Alternatively, organic and inorganic materials can be present in the form of a coating comprising organic materials and a stack of coatings comprising inorganic materials.

[0096] Refer again Figure 2 and Figure 3 The positive electrode 11 and the negative electrode 12 may each include a coated portion and uncoated portions 11a and 12a. The coated portion is the area on which the active material is coated on the current collector formed by the thin metal foil, and the uncoated portions 11a and 12a are the areas on which the active material is not coated.

[0097] Each of the positive electrode 11 and the negative electrode 12 has a sheet shape, and a plurality of positive electrodes 11 and a plurality of negative electrodes 12 may be stacked alternately, with a diaphragm 13 serving as an insulator interposed between them. However, this disclosure is not limited thereto. The positive electrodes 11 and the negative electrodes 12 may also be wound after the diaphragm 13 is interposed between them.

[0098] The housing 20 forms the external shape of the secondary battery 100 and can be made of a conductive metal such as aluminum, aluminum alloy, or nickel-plated steel. The housing 20 can provide space to accommodate the electrode assembly.

[0099] In the prismatic secondary battery 100, the housing 20 generally has a cuboid shape. More specifically, the housing 20 may include a front surface plate and a rear surface plate facing each other in the X-axis direction, a left side plate and a right side plate facing each other in the Y-axis direction, and a bottom surface plate 202 facing the Z-axis direction. Additionally, a portion in the Z-axis direction may be open. The front surface plate, rear surface plate, left side plate, right side plate, and bottom surface plate 202 may be formed as separate plate-shaped members and may be joined together at their connecting portions. However, this disclosure is not limited to this, and two or more plates can be manufactured by bending a single large-area plate at a 90° angle.

[0100] The cover assembly 30 may include a cover plate 31 that covers the opening of the housing 20. The housing 20 and the cover plate 31 may be made of a conductive material. Here, the terminal 21 electrically connected to the positive electrode 11 or the negative electrode 12 may protrude to the outside through the cover plate 31.

[0101] Terminals 21 protruding from the outside of the cover plate 31 can be formed as a pair. The pair of terminals 21 can be connected to the positive electrode 11 and the negative electrode 12, and can respectively serve as the positive electrode terminal and the negative electrode terminal of the secondary battery 100. Terminals 21 can be electrically connected to current collectors, which include a first current collector 40 and a second current collector 50 (hereinafter referred to as the positive electrode current collector and the negative electrode current collector) respectively bonded to the uncoated portions 11a of the positive electrode and 12a of the negative electrode by welding. The pair of terminals 21 can be welded to the positive electrode current collector 40 and the negative electrode current collector 50. However, this disclosure is not limited thereto; the terminals 21 can be integrally connected to the positive electrode current collector 40 and the negative electrode current collector 50.

[0102] The outer peripheral surface of the upper post of terminal 21 may be threaded and can be secured to cover plate 31 using a nut. However, this disclosure is not limited thereto. For example, terminal 21 may have a riveted structure and can be riveted to or welded to cover plate 31.

[0103] The cover plate 31 may be made of a thin sheet and is connected to the opening of the housing 20. An electrolyte injection port may be formed in the cover plate 31, and a sealing cap 33 is located in the electrolyte injection port. An exhaust port 34 may be formed in the cover plate 31.

[0104] The vent 34 can open and close due to changes in the internal pressure of the housing 20. That is, the vent 34 can seal the housing 20 by remaining closed during normal operation of the electrode assembly. When the internal pressure of the housing 20 increases to a set value or greater due to factors such as overcharging or a fire, the vent 34 can open. Therefore, emissions such as flames and gases can be discharged from the interior of the housing 20 through the vent.

[0105] An insulating member may be installed between the electrode assembly and the cover plate 31. The insulating member may include a first lower insulating member 60 and a second lower insulating member 70, and each of the first lower insulating member 60 and the second lower insulating member 70 may be installed between the electrode assembly and the cover plate 31.

[0106] According to this embodiment, one end of a separating member that can be mounted to face one side surface of the electrode assembly can be installed between the insulating member and the terminal 21. The separating member may include a first separating member 80 and a second separating member 90. Accordingly, the ends of the first separating member 80 and the second separating member 90, which can each face the side surface of the electrode assembly, can be located between the first lower insulating member 60 and the positive electrode terminal 21, and between the second lower insulating member 70 and the negative electrode terminal 21, respectively. As a result, the terminals 21 soldered to the positive electrode current collector 40 and the negative electrode current collector 50 can be connected to the ends of the first lower insulating member 60 and the first separating member 80, and the ends of the second lower insulating member 70 and the second separating member 90, respectively.

[0107] The module housing 200 can form the appearance of the secondary battery module 1 and provide space to accommodate multiple secondary batteries 100. The module housing 200 according to this disclosure may include a housing body 210 and a cover 220.

[0108] The outer shell body 210 can be formed in the shape of a box, having a hollow interior and an open side. However, the cross-sectional shape of the outer shell body 210 as seen in the XY plane is not limited to a quadrilateral shape, and can be various shapes such as polygonal, circular and elliptical shapes.

[0109] The cover 220 can be attached to the housing body 210 and can close the interior space of the housing body 210. As an example, the cover 220 can be formed to have a generally plate shape and can be positioned as an open side facing the housing body 210. The cover 220 can be secured to the housing body 210 by various types of connection methods such as bolting, welding, mating, etc.

[0110] Busbar 300 electrically connects multiple secondary batteries 100 to each other. Busbar 300 can be disposed between cover 220 and the secondary battery 100. Multiple busbars 300 can be provided. Each busbar 300 can connect a pair of adjacent secondary batteries 100 in series or in parallel. As an example, both sides of busbar 300 can be connected to the positive electrode terminal 21 of one of the pair of adjacent secondary batteries 100 and the negative electrode terminal 21 of the other. Accordingly, multiple secondary batteries 100 can be connected in series with each other via busbar 300. However, the connection form of busbar 300 is not limited to this, and it is also possible to connect multiple secondary batteries 100 in parallel by connecting both sides to the positive electrode terminal 21 of one of the pair of adjacent secondary batteries 100 and the positive electrode terminal 21 of the other, or by connecting both sides to the negative electrode terminal 21 of one of the pair of adjacent secondary batteries 100 and the negative electrode terminal 21 of the other.

[0111] Busbar 300 can be formed of conductive materials such as copper, aluminum, nickel, etc. The specific shape of busbar 300 is not limited to... Figure 1 The shape shown can be in the form of being able to electrically connect adjacent secondary batteries 100.

[0112] Multiple busbars 300 can be supported inside the module housing 200 by a busbar bracket H. The busbar bracket H can be formed into a flat plate shape. The busbar bracket H can be disposed between the cover 220 and the secondary battery 100. The busbars 300 can be fixed to the busbar bracket H by various types of connection methods such as mating connection, bolt connection, injection connection, etc. The busbar bracket H can include, for example, an electrically insulating polymer composite material.

[0113] The separator 400 is located in the gap between adjacent secondary batteries 100 spaced apart by a predetermined distance. For example, as Figures 1 to 3 As shown, when two secondary batteries 100 are arranged adjacent to each other by positioning the front surface plate of the casing 20 of one secondary battery 100 and the rear surface plate of the casing 20 of another secondary battery 100 facing each other with a gap between them, the separator 400 can be located in the gap between the front and rear surface plates. However, the arrangement of the separator 400 is not limited to this. For example, when multiple secondary batteries 100 are arranged along the Y-axis direction, the separator 400 can be located in the gap between the left side plate of the casing 20 of one secondary battery 100 and the right side plate of the casing 20 of the secondary battery 100 adjacent to that secondary battery 100.

[0114] Despite Figure 1Although not shown, the separator 400 may further be located between the secondary battery 100 and the outer surface panel of the outer casing body 210 of the module housing. More specifically, the separator 400 may be further disposed between the secondary battery 110 located at both ends of a plurality of secondary batteries 100 arranged in one direction and the surface of the outer casing body 210 adjacent to the secondary battery 100. For this purpose, the plurality of secondary batteries 100 may be arranged in the outer casing body 210 such that a predetermined gap is provided between the secondary battery 100 and a surface of the outer casing body 210 of the module housing.

[0115] The separator 400 is used to prevent thermal runaway from propagating to adjacent secondary batteries 100 in the event of a thermal event in one secondary battery 100. The separator 400 may be formed of a material having a melting point higher than that of the casing 20 or other components of the secondary battery 100. For example, the separator 400 may comprise a component formed of a metallic material having a melting point higher than that of aluminum (Al) and / or an insulating material such as ceramic.

[0116] Furthermore, if the secondary battery 100 expands, the separator 400 can prevent damage to the secondary battery module 1 by absorbing the increase in the size of the secondary battery 100. When the secondary battery 100 is in a normal, non-expanded state, the dimension of the separator 400 in the X-axis direction (hereinafter referred to as "thickness") does not change. On the other hand, when the secondary battery 100 expands, the thickness of the separator 400 can be reduced. Accordingly, even when the secondary battery 100 expands, the overall size of the secondary battery module 1 remains unchanged, especially the length in the X-axis direction, thereby preventing damage to the cover plate 31, module housing 200, etc.

[0117] According to this disclosure, the thickness of the separator 400 can be changed by using an electrical signal applied to it. Furthermore, the amount of thickness change can also be controlled by adjusting the amplitude of the applied electrical signal. Accordingly, when an expansion state of the secondary battery 100 is detected, preventative measures can be proactively taken to mitigate the expansion phenomenon by adjusting the electrical signal applied to the separator 400 based on the detected expansion state, thereby preemptively changing the thickness of the separator 400. Additionally, by reducing the thickness of the separator 400 before the expanded secondary battery 100 applies pressure to it, pressure applied to the separator 400 from the outside of the secondary battery 100 can be suppressed.

[0118] According to this disclosure, the shape of the separator 400 is not limited. For example, when the housing 20 of the secondary battery 100 has a generally cuboid shape, the separator 400 may have a hexahedral shape, having a rectangular surface that is substantially the same in size and shape as the surface of the housing 20 adjacent to the separator 400. In this case, the separator 400 may be in the form of a plate or sheet with a predetermined thickness. However, this disclosure is not limited thereto, and the separator 400 may differ in size and / or shape from the surface of the housing 20 adjacent to it. In addition, the thickness of the separator 400 is not particularly limited, but may be determined by taking into account the effectiveness of preventing the propagation of thermal runaway, the size of the module housing 200 of the secondary battery module 1, the number of secondary batteries 100 included in the secondary battery module 1, etc.

[0119] According to this disclosure, the separator 400 can be a component whose thickness varies in response to an applied electrical signal, i.e., a component with variable thickness. For example, when a predetermined electrical signal (voltage or current) is applied, the thickness of the separator 400 (i.e., its dimension (e.g., length) in the X-axis direction) can be reduced. In this case, the amount of reduction in the thickness of the separator 400 can vary depending on the amplitude of the applied electrical signal. For example, the amount of reduction in the thickness of the separator 400 can be proportional to the amplitude of the applied electrical signal. However, the amount of reduction in thickness and the amplitude of the electrical signal do not necessarily have to be linearly proportional, and can exhibit a step-like proportional relationship or follow a predetermined curve function.

[0120] According to one aspect, the partition member 400 can be a variable-volume member having a volume that changes in response to an applied electrical signal. For example, the partition member 400 can be a member whose overall volume decreases when a predetermined electrical signal (voltage or current) is applied. Accordingly, as the volume of the partition member 400 decreases, the thickness of the partition member 400 (e.g., its dimension in the X-axis direction) also decreases.

[0121] Figure 4A yes Figure 1 A perspective view of an example of the partition members included in the secondary battery module 1, and Figure 4B yes Figure 4A The front view of the dividing component. (Reference) Figure 4A and 4B The separating member 400 includes one or more electrically variable elements 410, a pair of electrode members (e.g., electrode plates) 420 and a pair of insulating members (e.g., insulating plates) 430.

[0122] The electrically variable elements 410 are configured such that at least their thickness varies in response to an electrical signal applied through a pair of electrode plates 420. There are no particular limitations on the type of electrically variable elements 410 in this disclosure. The electrically variable elements 410 may be formed of piezoelectric or electroactive polymer materials. For example, the electrically variable elements 410 may include piezoelectric elements and / or electroactive polymer elements. Piezoelectric elements or electroactive polymer elements have the advantage of superior durability compared to elastic elements such as springs or rubber that can be compressed or stretched in response to external pressure.

[0123] In the case of a piezoelectric element, when a predetermined voltage is applied to both ends of the piezoelectric element through a pair of electrode plates 420, the inverse piezoelectric effect can cause a reduction in the volume of the piezoelectric element or at least a reduction in its thickness. Accordingly, the dimensions of the separating member 400 including the piezoelectric element can be reduced, at least in the lateral direction. There are no restrictions on the type of piezoelectric element, and currently used piezoelectric elements as well as those developed and used in the future can be used, as long as they exhibit the inverse piezoelectric effect.

[0124] In the case of an electroactive polymer element, when a predetermined voltage is applied to both ends of the electroactive polymer element through a pair of electrode plates 420, the volume of the electroactive polymer element can be reduced, or at least the thickness of the electroactive polymer element can be reduced, due to the Maxwell force generated between the electrode plates 420. Accordingly, the dimensions of the separating member 400 including the electroactive polymer element can be reduced, at least in the lateral direction. There is no limitation on the type of electroactive polymer element, and currently used electroactive polymer elements as well as those developed and used in the future can be used, as long as they exhibit the effect of reducing thickness in the direction of voltage application due to the Maxwell force and the crosslinking reaction between the polymer.

[0125] The thickness of the electrically variable element 410 (i.e. Figure 4B The length in the lateral direction (in the image) can be set considering the size of the secondary battery 100. In some examples, the thickness of the electrically variable element 410 can be in the range of 0.5 mm to 10 mm. When the thickness of the electrically variable element 410 is less than or equal to 0.5 mm, it is difficult to obtain the desired thickness change in the separator 400 because the thickness change corresponding to the amplitude of the electrical signal is small. When the thickness of the electrically variable element 410 is greater than or equal to 10 mm, the size of the secondary battery 100 increases, which leads to an increase in the size of the secondary battery module 1 including multiple secondary batteries 100 and also reduces the space utilization efficiency inside the module housing 200.

[0126] The electrically variable element 410 may be, for example, in the form of a single plate or sheet having a predetermined thickness. The shape of the electrically variable element 410 (the shape of the cross-sectional plane of the electrically variable element 410 facing the electrode plate 420) may be substantially the same as the shape of the electrode plate 420. In addition, the size of the electrically variable element 410 may be substantially equal to the size of the electrode plate 420. However, this disclosure is not limited thereto, and the shape or size of the electrically variable element 410 may differ from the shape or size of the electrode plate 420.

[0127] Alternatively, the electrically variable element 410 may comprise a plurality of unit electrically variable elements. In this case, the plurality of unit electrically variable elements may be spaced apart from each other in the plane of a pair of electrode plates 420. For example, the plurality of unit electrically variable elements may be distributed and arranged in a grid pattern in a plane parallel to the electrode plates 420. When a voltage is applied to the pair of electrode plates 420 and the thickness of the electrically variable element 410 decreases, the electrically variable element 410 expands in a direction parallel to the plane of the electrode plates 420. When the electrically variable element 410 is integrally formed into a single plate or sheet shape, the expansion of the electrically variable element 410 may be insufficient, and therefore the reduction in the thickness of the electrically variable element 410 may be insufficient. However, when the electrically variable element 410 comprises a plurality of unit electrically variable elements spaced apart from each other, there is sufficient free space for each electrically variable element to expand in a plane direction parallel to the plane of the electrode plates 420 while reducing its thickness. Therefore, a greater thickness reduction effect can be achieved.

[0128] A pair of electrode plates 420 serve as electrode components for applying electrical signals to the electrically variable element 410. The pair of electrode plates 420 may be formed of a conductive material. As will be described below, a predetermined power supply (voltage supply device) may be electrically connected to the pair of electrode plates 420.

[0129] The pair of electrode plates 420 can also serve as support members for the electrically variable element 410. In one embodiment, the pair of electrode plates 420 may be located on the outer side of the electrically variable element 410 in the X-axis direction. The pair of electrode plates 420 are preferably formed of a material with excellent heat resistance. More specifically, the pair of electrode plates 420 may be formed of a material that does not melt even during a thermal runaway event and is able to maintain its structure. For example, the pair of electrode plates 420 may be formed of a high-melting-point metallic material such as stainless steel or its alloys (i.e., a metallic material having a melting point higher than that of the material of the casing 20 of the secondary battery 100), but this disclosure is not limited thereto.

[0130] A pair of insulating plates 430 serve as insulating members to maintain electrical insulation between adjacent secondary batteries 100. The pair of insulating plates 430 can also be used to block or suppress heat transfer between adjacent secondary batteries 100. Accordingly, even if a thermal runaway event occurs in any one of the secondary batteries 100, the propagation of thermal runaway to adjacent secondary batteries 100 can be suppressed. The pair of insulating plates 430 can be formed of one or more of alumina, mica, and silica gel. However, this disclosure is not limited to these examples. In one embodiment, the pair of insulating plates 430 can be located on the outer side of a pair of electrode plates 420 in the X-axis direction.

[0131] Figure 5A and Figure 5B This is a cross-sectional view schematically illustrating another example of a secondary battery module according to the present disclosure. Figure 5A Example of a secondary battery 100 in a state where it does not expand, and Figure 5B An example is given of the state in which the secondary battery 100 expands. Here, the state in which the secondary battery 100 does not expand includes not only the case where the secondary battery 100 maintains its initial shape and size, but also the case where, even if expansion has occurred, the degree of expansion is small enough that the change in shape and / or the increase in volume is not significant. On the other hand, the state in which the secondary battery 100 expands refers to the case where the degree of expansion of the secondary battery 100 exceeds a certain level, causing a significant change in shape and volume from its initial state.

[0132] Depending on its use, expansion may occur in the secondary battery 100 for various reasons. As an example, depending on the state of charge, expansion may occur in the secondary battery 100, and the degree of expansion may be proportional to the state of charge of the secondary battery. As another example, depending on the degree of use, expansion may occur in the secondary battery 100, and the degree of expansion may be proportional to the number of charge-discharge cycles of the secondary battery 100.

[0133] refer to Figure 5A and Figure 5B The secondary battery module according to this embodiment may further include a voltage applying device 500. As described above, the voltage applying device 500 is a power source for applying a predetermined voltage to the separator 400, and more specifically to a pair of electrode plates 420. In one embodiment, the voltage applying device 500 may be a power source configured to generate an electrical signal and apply the electrical signal to the separator 400.

[0134] There are no limitations on the type or implementation of the voltage applying device 500. For example, the voltage applying device 500 may be the same power supply device provided in the circuitry of the secondary battery module, or it may be a separate power supply device mounted to apply voltage to the separating member 400. In the latter case, the voltage applying device 500 may be mounted on a printed circuit board (PCB) of the circuitry (e.g., a battery management system (BMS)) of the secondary battery module. However, this disclosure is not limited thereto.

[0135] When the secondary battery does not expand at 100 (reference) Figure 5A When the voltage applying device 500 does not apply any voltage to the separating member 400, the separating member 400 maintains its initial thickness t1. On the other hand, when the secondary battery 100 expands (refer to...), Figure 5B When the voltage applying device 500 applies a predetermined voltage to the separating member 400, the thickness of the separating member 400 decreases, and it has a thickness t2 that is smaller than the initial thickness t1.

[0136] The secondary battery module 1 according to this disclosure may further include a sensor (not shown) for detecting (e.g., estimating or determining) whether the secondary battery 100 is in an inflated state. In one embodiment, an electrical signal may be applied to the separating member 400 based on the sensor's detection result. There is no limitation on the type of sensor, and various forms of sensors can be implemented, as long as they are capable of estimating or determining the inflated state. In one embodiment, a voltage applying device 500 may be configured to generate an electrical signal having an amplitude corresponding to the estimated or determined degree of inflated state.

[0137] Typically, expansion in the secondary battery 100 occurs proportionally to its state of charge. Accordingly, a sensor can estimate that the secondary battery 100 is in an expanded state when its state of charge is greater than or equal to a predetermined threshold. According to an embodiment, the expansion state can also be estimated based on the overall state of charge of the secondary battery module 1, which includes a plurality of secondary batteries 100.

[0138] Furthermore, expansion may occur in the secondary battery 100 in proportion to the number of charge-discharge cycles. Accordingly, the sensor can estimate that the secondary battery 100 is in an expanded state when the number of charge-discharge cycles of the secondary battery 100 is greater than or equal to a predetermined threshold.

[0139] The sensor can also measure the dimensions of the secondary battery 100 or the secondary battery module 1 directly or indirectly (in... Figure 5A and Figure 5B The sensor estimates whether the secondary battery 100 is in an expanded state by measuring the length in the lateral direction of the secondary battery 100. For example, when the measured size of the secondary battery 100 increases to a value greater than or equal to a predetermined threshold compared to its initial size, the sensor can determine that the secondary battery 100 is expanded.

[0140] As described above, in the secondary battery module according to this disclosure, when the secondary battery 100 expands, a predetermined voltage is applied to the separator 400 to reduce its thickness. Accordingly, even when the secondary battery 100 expands, the reduction in the thickness of the separator 400 can prevent or suppress the increase in the overall size of the secondary battery module, especially... Figure 5B The increase in length in the lateral direction. As a result, even when the secondary battery 100 expands, it is possible to prevent pressure from being applied to the cover plate 31 and / or the side wall of the module housing 200, or to reduce pressure applied to the cover plate 31 and / or the side wall of the module housing 200. Therefore, it is possible to prevent or suppress cracking or damage to structures (such as the cover plate 31 of the secondary battery 100 or the module housing 200).

[0141] According to one aspect of this disclosure, the amplitude of the voltage applied to the separating member 400 can be varied. For example, the voltage applying device 500 can be a variable power source. That is, the amplitude of the voltage applied from the voltage applying device 500 can vary. For this purpose, the secondary battery module may further include a control unit (not shown) for controlling the amplitude of the voltage applied from the voltage applying device 500. The control unit can control the amplitude of the voltage applied from the voltage applying device 500 based on the degree of expansion of the secondary battery 100. More specifically, the control unit can control the amplitude of the applied voltage to be relatively large when the secondary battery 100 is significantly expanded, and control the amplitude of the applied voltage to be relatively small when the secondary battery 100 is only slightly expanded.

[0142] The sensor can estimate or determine whether the secondary battery 100 is in an expanded state, and can also estimate or determine the degree of expansion of the secondary battery 100. For example, the sensor can estimate the degree of expansion based on the state of charge and / or the number of charge-discharge cycles of the secondary battery 100, or determine the degree of expansion based on the measured dimensions of the secondary battery 100 or the secondary battery module 1.

[0143] According to embodiments of this disclosure, deformation of the secondary batteries can be actively compensated by providing a separating member between adjacent secondary batteries that can vary in thickness in response to an external control signal. In particular, by taking into account the expansion of the secondary batteries caused by the state of charge and / or the number of charge-discharge cycles, the possibility of damage to the module structure (such as the module housing or cover) can be reduced in advance.

[0144] However, those skilled in the art will understand that the effects achievable through this disclosure are not limited to those already described above, and other advantages of this disclosure will become clearer from the above detailed description.

[0145] Although this disclosure has been described with reference to exemplary embodiments illustrated in the accompanying drawings, it should be understood that this disclosure is not limited to the disclosed embodiments, but covers various modifications and equivalent arrangements.

Claims

1. A secondary battery module, comprising: Multiple secondary batteries are arranged along the first direction; as well as A separator is located in the gap between two adjacent secondary batteries among the plurality of secondary batteries, and the separator has a variable length at least in the first direction in response to an electrical signal applied to the separator.

2. The secondary battery module according to claim 1, The length of the separating member is variable, at least in the first direction, depending on the magnitude of the voltage applied to the separating member.

3. The secondary battery module according to claim 2, wherein the separating member comprises: One or more electrically variable elements, each configured to have a variable length at least in the first direction according to the magnitude of the voltage; as well as A pair of electrode components are configured to apply the voltage to the electrically variable element.

4. The secondary battery module of claim 3, wherein the electrically variable element is configured to change shape according to the magnitude of the voltage, and The pair of electrode members are located on the outside of each of the one or more electrically variable elements in the first direction.

5. The secondary battery module according to claim 4, wherein the electrically variable element is formed of a piezoelectric material or an electroactive polymer material.

6. The secondary battery module according to claim 4, wherein each of the pair of electrode components is formed of a metallic material having a melting point higher than that of the material of the casing of each of the plurality of secondary batteries.

7. The secondary battery module according to claim 4, wherein the separating member further comprises a pair of insulating members located on the outer side of the pair of electrode members in the first direction.

8. The secondary battery module according to claim 7, wherein each of the pair of insulating members is formed of one or more materials selected from alumina, mica and silicone.

9. The secondary battery module according to claim 1, further comprising a sensor configured to detect whether at least one of the plurality of secondary batteries is swollen. The electrical signal is applied to the separating member based on the detection result of the sensor.

10. The secondary battery module of claim 9, further comprising a power supply configured to generate the electrical signal and apply the electrical signal to the separating member. The sensor is configured to estimate the degree of expansion based on at least one of the state of charge of at least one of the plurality of secondary batteries and the number of charge-discharge cycles. The power supply is configured to generate an electrical signal having an amplitude corresponding to the estimated degree of expansion, and The length of the separating member is variable in the first direction according to the amplitude of the electrical signal applied to the separating member.

11. The secondary battery module of claim 9, further comprising a power supply configured to generate the electrical signal and apply the electrical signal to the separating member. The sensor is configured to determine the degree of expansion based on the dimension of at least one of the plurality of secondary batteries in the first direction. The power supply is configured to generate an electrical signal having an amplitude corresponding to the determined degree of expansion, and The length of the separating member is variable in the first direction according to the amplitude of the electrical signal applied to the separating member.

12. A secondary battery module, comprising: Multiple secondary batteries are arranged along the first direction; as well as A separator, located in the gap between two adjacent secondary cells among the plurality of secondary cells, has a variable thickness in response to an electrical signal applied to it. The separating member includes: An electrically variable element is configured to change its size at least in the first direction according to the amplitude of the electrical signal; A pair of electrode plates, located on the outer side of the electrically variable element in the first direction, and configured to apply the electrical signal to the electrically variable element; and A pair of insulating plates are located on the outer side of the pair of electrode plates in the first direction.

13. The secondary battery module according to claim 12, wherein the electrovariable element comprises one or more of a piezoelectric element and an electroactive polymer element.

14. The secondary battery module according to claim 12, wherein the electrically variable element is a sheet having thickness in the first direction.

15. The secondary battery module according to claim 12, wherein the electrically variable element comprises a plurality of electrically variable elements, and The electrically variable elements are spaced apart from each other in a plane parallel to the electrode plate.

16. The secondary battery module of claim 12, wherein each of the pair of electrode plates is formed of a metallic material having a melting point higher than that of the material of the casing of each of the plurality of secondary batteries.

17. The secondary battery module according to any one of claims 12 to 16, wherein each of the pair of insulating plates is formed of one or more materials selected from alumina, mica and silicone.

18. The secondary battery module according to any one of claims 12 to 16, further comprising a sensor configured to detect whether at least one of the plurality of secondary batteries is swollen. The electrical signal is applied to the separating member based on the detection result of the sensor.

19. The secondary battery module of claim 18, further comprising a power supply configured to generate the electrical signal and apply the electrical signal to the pair of electrode plates. The sensor is configured to estimate the degree of expansion based on at least one of the state of charge of at least one of the plurality of secondary batteries and the number of charge-discharge cycles. The power supply is configured to generate an electrical signal having an amplitude corresponding to the estimated degree of expansion, and The thickness of the electrically variable element is variable in the first direction according to the amplitude of the electrical signal applied to the electrically variable element.

20. The secondary battery module of claim 18, further comprising a power supply configured to generate the electrical signal and apply the electrical signal to the pair of electrode plates. The sensor is configured to determine the degree of expansion based on the dimension of at least one of the plurality of secondary batteries in the first direction. The power supply is configured to generate an electrical signal having an amplitude corresponding to the determined degree of expansion, and The thickness of the electrically variable element is variable in the first direction according to the amplitude of the electrical signal applied to the electrically variable element.

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