Battery cell, and battery pack and vehicle comprising same

Abstract

The present invention provides a battery cell comprising: a jelly-roll-type electrode assembly in which a first electrode and a second electrode and a separator interposed therebetween are wound in one direction; a battery housing accommodating the electrode assembly by means of a sidewall part, a bottom part connected to one end of the sidewall part in the winding axis direction, and an open end formed at the other end of the sidewall part in the winding axis direction, and electrically connected to the second electrode; an electrode terminal passing through a through-hole formed in the bottom part of the battery housing and electrically connected to the first electrode; and an insulator interposed between the bottom part of the battery housing and the electrode assembly, wherein a gas adsorption layer is formed on at least one surface of the insulator.

Description

Battery cells, battery packs including the same, and automobiles

[0001] The present invention relates to a battery cell, a battery pack including the same, and an automobile.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2025-0038187 dated March 25, 2025, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003]

[0004] Secondary batteries, which offer high applicability across product lines and possess electrical characteristics such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that operate via electric power sources.

[0005] These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency, as they not only have the primary advantage of being able to drastically reduce the use of fossil fuels but also the advantage of not generating any by-products from the use of energy.

[0006] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells is approximately 2.5V to 4.5V.

[0007] Therefore, if a higher output voltage is required, a battery module or battery pack is configured by connecting multiple battery cells in series. Additionally, a battery module or battery pack is configured by connecting multiple battery cells in parallel depending on the required charge / discharge capacity. Accordingly, the number of battery cells included in the battery module or battery pack and the electrical connection type can be varied according to at least one of the required output voltage and charge / discharge capacity.

[0008] Cylindrical, prismatic, and pouch-type battery cells are known as types of battery cells. In the case of a cylindrical battery cell, an insulating separator is interposed between a positive plate and a negative plate, and this is wound to form a jelly-roll type electrode assembly, which is then inserted into a battery housing along with an electrolyte to constitute a battery.

[0009] Meanwhile, after the assembly process, cylindrical battery cells undergo an activation process and subsequent cycles using electrical energy to activate the cells and verify stability, during which various gases are generated. While gases generated during the activation process can be removed through a degassing process, there is a problem in that gases generated during the subsequent cycles are difficult to remove.

[0010] Gas that is not removed becomes trapped in the empty spaces and electrode assemblies inside the battery cell, which can contribute to the degradation of the battery cell.

[0011] The present invention is designed to solve the aforementioned problems, and the purpose of the present invention is to provide an insulator capable of removing gas generated according to a cycle, a battery cell including the same, a battery pack, and an automobile.

[0012] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below.

[0013]

[0014] To achieve these objectives, according to one aspect of the present invention, a battery cell of the following embodiment, a battery pack including the same, and a vehicle are provided.

[0015] According to a first embodiment, a battery cell is provided comprising: an electrode assembly in the form of a jelly-roll, wherein a first electrode and a second electrode and a separator interposed between them are wound in one direction; a battery housing that accommodates the electrode assembly through a side wall portion, a bottom portion connected to one end in the direction of the winding axis of the side wall portion, and an open end formed at the other end in the direction of the winding axis of the side wall portion, and is electrically connected to the second electrode; an electrode terminal provided through a through hole formed in the bottom portion of the battery housing and is electrically connected to the first electrode; and an insulator interposed between the bottom portion of the battery housing and the electrode assembly; wherein a gas adsorption layer is formed on at least one surface of the insulator.

[0016] According to the second embodiment, in the first embodiment, the gas adsorption layer may include gas adsorption particles.

[0017] According to the third embodiment, in the second embodiment, the gas adsorption layer may further include a binder polymer.

[0018] According to the fourth embodiment, in any one of the second to third embodiments, the gas adsorption particles may comprise activated carbon, aerogel, metal-organic framework (MOF), zeolite, carbon nanotube (CNT), graphene oxide, silica gel, or a combination thereof.

[0019] According to the fifth embodiment, in any one of the third to fourth embodiments, the binder polymer is polyvinylidene fluoride, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polybutylacrylate, polybutylmethacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyethylene-co-vinyl acetate copolymer, polyethylene oxide, polyarylate, cellulose acetate It may be cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, or may contain two or more of these.

[0020] According to the sixth embodiment, in any one of the first to fifth embodiments, the gas adsorption layer may be formed on the other side of the surface of the insulator facing the battery housing.

[0021] According to the seventh embodiment, in any one of the first to sixth embodiments, the coating amount of the gas adsorption layer is 0.1 g / m² 2 Up to 1.0 g / m² 2 It may be within the range of.

[0022] According to the eighth embodiment, in any one of the first to seventh embodiments, the gas adsorption layer may be coated at a ratio of 50% to 95% based on 100% of one surface of the insulator.

[0023] According to the ninth embodiment, in any one of the first to eighth embodiments, the insulator may have a shape corresponding to the radial cross-sectional shape of the jelly-roll type electrode assembly.

[0024] According to the 10th embodiment, in any one of the 1st to 9th embodiments, the insulator may have an uncoated portion formed on the outer periphery in the circumferential direction.

[0025] According to the 11th embodiment, in any one of the 1st to 10th embodiments, the insulator may include an insulator hole at the center, and an uncoated portion may be formed on the outer periphery in the circumferential direction of the insulator hole.

[0026] According to the 12th embodiment, in any one of the 1st to 11th embodiments, the insulator may include at least one electrolyte hole.

[0027] According to the 13th embodiment, a battery pack comprising a battery cell according to any one of the 1st to 12th embodiments is provided.

[0028] According to the 14th embodiment, a vehicle comprising a battery pack according to the 13th embodiment is provided.

[0029]

[0030] A battery cell according to one embodiment of the present invention can prevent gas from being trapped in the empty space inside the battery cell by removing gas generated during the cycle.

[0031] A battery cell according to one embodiment of the present invention can reduce the degradation of the battery cell by removing gas generated during the cycle and preventing gas from being trapped in the electrode assembly.

[0032] A battery cell according to one embodiment of the present invention can suppress additional side reactions by removing gas generated during the cycle.

[0033] A battery cell according to one embodiment of the present invention can reduce the internal pressure inside the battery cell by removing gas generated during the cycle.

[0034] According to another aspect of the present invention, a battery pack manufactured using a battery cell with improved degradation characteristics and an automobile including the same can be provided.

[0035]

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

[0037] FIG. 1 is a drawing showing the appearance of a battery cell according to one embodiment of the present invention.

[0038] FIG. 2 is a cross-sectional view showing the internal structure of a battery cell according to one embodiment of the present invention.

[0039] FIG. 3 is a cross-sectional view showing the internal structure of a battery cell according to one embodiment of the present invention.

[0040] FIG. 4 is a schematic diagram showing an insulator included in a battery cell according to one embodiment of the present invention.

[0041] FIG. 5 is a schematic diagram showing an insulator included in a battery cell according to one embodiment of the present invention.

[0042] FIG. 6 is a schematic diagram showing a battery pack including a battery cell according to an embodiment of the present invention.

[0043] FIG. 7 is a schematic diagram showing an automobile including a battery pack according to an embodiment of the present invention.

[0044]

[0045] Terms and words used in this specification and claims shall not be interpreted as being limited to their ordinary or dictionary meanings, but shall be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0046] The terms used in this specification are used merely to describe exemplary embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0047] <Definition>

[0048] Throughout this specification, when a part is described as 'comprising' a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0049] Throughout this specification, terms such as "first," "second," etc. are used to describe various components, but these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may be the second component.

[0050] Throughout the entire specification, unless specifically stated otherwise, each component may be singular or plural.

[0051] Throughout the entire specification, the statement that any configuration is disposed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is disposed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration disposed on (or below) said component.

[0052] Throughout this specification, where it is stated that one component is "connected," "coupled," or "connected" to another component, it should be understood that said components may be directly connected or connected to each other, but that other components may be "interposed" between each component, or that each component may be "connected," "coupled," or "connected" through other components.

[0053] Throughout the entire specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less unless specifically stated otherwise.

[0054] Throughout this specification, the direction along the longitudinal direction of the winding axis of a jelly-roll type electrode assembly is referred to as the winding axis direction, and the direction approaching or moving away from the winding axis is referred to as the radial direction. In particular, the direction approaching the winding axis is referred to as the centripetal direction, and the direction moving away from the winding axis is referred to as the centrifugal direction.

[0055]

[0056] FIG. 1 is a drawing showing the external appearance of a battery cell according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the internal structure of a battery cell according to an embodiment of the present invention, FIG. 3 is a cross-sectional view showing the internal structure of a battery cell according to an embodiment of the present invention, FIG. 4 is a schematic drawing showing an insulator included in a battery cell according to an embodiment of the present invention, FIG. 5 is a schematic drawing showing an insulator included in a battery cell according to an embodiment of the present invention, FIG. 6 is a schematic drawing showing a battery pack including a battery cell according to an embodiment of the present invention, and FIG. 7 is a schematic drawing showing an automobile including a battery pack according to an embodiment of the present invention. The following description refers to the drawings.

[0057]

[0058] Referring to FIGS. 1 to 3, a battery cell (1) according to one embodiment of the present invention comprises an electrode assembly (10), a battery housing (20), an electrode terminal (40), and an insulator (70). In addition to the components described above, the battery cell (1) may further include a lead (30) and / or a first current collector (60) and / or a second current collector (80) and / or a terminal gasket (50) and / or a sealing gasket (90).

[0059]

[0060] Electrode Assembly

[0061] The electrode assembly (10) comprises a first electrode having a first polarity, a second electrode having a second polarity, and a separator interposed between the first electrode and the second electrode. The first electrode is a positive or negative electrode, and the second electrode corresponds to an electrode having a polarity opposite to that of the first electrode.

[0062] In one embodiment of the present invention, the electrode assembly (10) may have, for example, a jelly-roll shape. That is, the electrode assembly (10) may be manufactured by winding a laminate formed by stacking a first electrode and a second electrode having a sheet shape at least once with a separator interposed between them, based on the center of the winding. In this case, an additional separator may be provided on the outer surface of the electrode assembly (10) to insulate it from the battery housing (20). Any jelly-roll structure known in the art may be applied to the present invention without limitation.

[0063] In one embodiment of the present invention, the first electrode may include a first electrode current collector and a first electrode active material coated on one or both sides of the first electrode current collector. A blank portion in which the first electrode active material is not coated may exist at one end of the first electrode current collector in the winding axis direction (i.e., the direction parallel to the Z-axis). The blank portion will be referred to as the first portion (11) below. The first portion (11) may be provided on the upper side in the height direction (the direction parallel to the Z-axis) of the electrode assembly (10) housed within the battery housing (20). That is, the first electrode current collector includes a first portion (11) in which the active material layer is not coated at the long end and is exposed to the outside of the separator, and a part of the first portion (11) may be used as an electrode tab itself. The first portion (11) may be, for example, a positive electrode tab.

[0064] In one embodiment of the present invention, at least a portion of the first part (11) may include a plurality of segments divided along the winding direction of the electrode assembly (10). In this case, the plurality of segments may be bent along the radial direction of the electrode assembly (10). The bent plurality of segments may be overlapped in multiple layers. In this case, the first part coupling portion of the first current collector (60), which will be described later, may be coupled to the area where the plurality of segments are overlapped in multiple layers. Meanwhile, the electrode assembly (10) may have a welding target area, which is an area where the number of overlapping layers of the segments of the first part (11) is maintained constant along the radial direction of the electrode assembly (10). In this area, since the number of overlapping layers is maintained at approximately the maximum, it may be advantageous for the welding of the first current collector (60), which will be described later, and the first part (11) to be performed within this area. This is to prevent the laser beam from penetrating the first part (11) and damaging the electrode assembly (10) when the laser output is increased to improve welding quality, for example when laser welding is applied. In addition, this is to effectively prevent foreign substances, such as welding spatter, from entering the interior of the electrode assembly (10).

[0065] In one embodiment of the present invention, the second electrode comprises a second electrode current collector and a second electrode active material coated on one or both sides of the second electrode current collector. At the other end of the second electrode current collector in the winding axis direction (direction parallel to the Z-axis), there exists a non-coated portion where the second electrode active material is not coated. The non-coated portion functioning as the second non-coated portion is hereinafter referred to as the second portion (12). The second portion (12) is provided at the lower end in the height direction (direction parallel to the Z-axis) of the electrode assembly (10) housed within the battery housing (20). That is, the second electrode current collector may include a second portion (12) that is not coated with an active material layer at the long end and is exposed to the outside of the separator, and at least a portion of the second portion (12) may be used as an electrode tab itself. The second portion (12) may be, for example, a negative electrode tab. Meanwhile, at least a portion of the second part (12) may include a plurality of segments divided along the winding direction of the electrode assembly (10). In this case, the plurality of segments may be bent along the radial direction of the electrode assembly (10). The bent plurality of segments may be overlapped in multiple layers. In this case, the second part coupling portion of the second current collector (80), which will be described later, may be coupled to the area where the plurality of segments are overlapped in multiple layers. Meanwhile, the electrode assembly (10) may have a welding target area, which is an area where the number of overlapping layers of the segments of the second part (12) is maintained constant along the radial direction of the electrode assembly (10). In this area, since the number of overlapping layers is maintained at a maximum, it may be advantageous for the welding of the second current collector (80) and the second part (12), which will be described later, to be performed within this area. This is to prevent the laser beam from penetrating the second part (12) and damaging the electrode assembly (10) when the laser output is increased to improve welding quality, for example when laser welding is applied.In addition, this is intended to effectively prevent foreign substances, such as welding spatter, from entering the interior of the electrode assembly (10).

[0066] In one embodiment of the present invention, the first part (11) and the second part (12) extend in opposite directions, i.e., axially outward, along the height direction (direction parallel to the Z-axis) of the battery cell (1). The first part (11) extends toward a bottom portion formed at one end of the winding axis direction of the battery housing (20), and the second part (12) extends toward an open end formed at the other end of the winding axis direction of the battery housing (20).

[0067] In one embodiment of the present invention, the positive active material coated on the positive electrode and the negative active material coated on the negative electrode may be used without limitation as long as they are active materials known in the art.

[0068] In one embodiment of the present invention, the positive active material is a general chemical formula A[A x M y ]O 2+z It may include an alkali metal compound represented by (A contains at least one element among Li, Na and K; M contains at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Sc, Ru, and Cr; x ≥ 0, 1 ≤ x+y ≤ 2, -0.1 ≤ z ≤ 2; the stoichiometric coefficients of the components included in x, y, z and M are selected so that the compound maintains electrical neutrality).

[0069] In one embodiment of the present invention, the positive active material is an alkali metal compound xLiM disclosed in US6,677,082, US6,680,143, etc. 1 O2-(1-x)Li2M 2 O3(M 1 It comprises at least one element having an average oxidation state of 3; M 2It contains at least one element having an average oxidation state of 4; 0≤x≤1).

[0070] In one embodiment of the present invention, the positive active material is of the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1 It contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Mg, and Al; M 2 ... comprises at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, As, Sb, Ge, and S; M 3 ... comprises a halogen element optionally containing F; 0 < a ≤ 2, 0 ≤ x ≤ 1, 0 ≤ y < 1, 0 ≤ z < 1; a, x, y, z, M 1 , M 2 , and M 3 The stoichiometric coefficient of the component included in the compound is selected so that the compound maintains electrical neutrality), or may be a lithium metal phosphate represented as Li3M2(PO4)3 [M comprises at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg and Al].

[0071] In one embodiment of the present invention, the positive active material may include primary particles and / or secondary particles formed by the aggregation of primary particles.

[0072] In one embodiment of the present invention, the negative electrode active material may be a carbon material, lithium metal or lithium metal compound, silicon or silicon compound, tin or tin compound, etc. Metal oxides such as TiO2 and SnO2 with a potential of less than 2V may also be used as negative electrode active materials. As for the carbon material, low-crystallinity carbon, high-crystallinity carbon, etc. may all be used.

[0073] In one embodiment of the present invention, the separator may be a porous polymer film, for example, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., used alone or laminated therefrom. As another example, the separator may be a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high-melting-point glass fibers, polyethylene terephthalate fibers, etc.

[0074] In one embodiment of the present invention, at least one surface of the separation membrane may include a coating layer of inorganic particles. It is also possible for the separation membrane itself to be composed of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure bonded with a binder such that interstitial volume exists between adjacent particles.

[0075] In one embodiment of the present invention, the inorganic particles may be composed of an inorganic material having a dielectric constant of 5 or higher. As a non-limiting example, the inorganic particles may be Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), Pb(Mg3Nb 2 / 3It may include at least one material selected from the group consisting of )O3-PbTiO3(PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0076] Meanwhile, the battery cell (1) of the present invention may have an electrolyte injected into the battery housing (20). At this time, the electrolyte is A + B - It may be a salt having a structure like that. Here, A + is Li + , Na + , K + It includes alkali metal cations such as or ions composed of combinations thereof. And B - is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - ,　 CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C -, (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - and (CF3CF2SO2)2N - It includes one or more anions selected from the group consisting of

[0077] The electrolyte may also be dissolved in an organic solvent. As organic solvents, propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), gamma-butyrolactone (γ-butyrolactone), or mixtures thereof may be used.

[0078]

[0079] Battery Housing

[0080] The battery housing (20) accommodates the electrode assembly (10) through a side wall portion, a bottom portion connected to one end of the side wall portion in the direction of the winding axis, and an open end formed at the other end of the side wall portion in the direction of the winding axis, and is electrically connected to the second electrode.

[0081] The battery housing (20) may be made of a conductive material, such as metal, for example. The material of the battery housing (20) may be steel, stainless steel, or nickel-plated steel, for example.

[0082] The battery housing (20) has an open end formed on one side, that is, on the lower side based on FIG. 2, and accommodates an electrode assembly (10) through the open end. Additionally, the battery housing (20) has a bottom end (or closed end) formed on the opposite side of the open end, that is, on the upper side based on FIG. 2. A through hole is formed in the bottom end. The side wall and bottom end of the battery housing (20) may be formed integrally. Alternatively, the side wall and bottom end of the battery housing (20) may be provided separately from each other and joined together by welding or the like. The upper surface (a surface parallel to the XY plane) of the battery housing (20), that is, the outer surface of the bottom end, has a roughly flat shape. The battery housing (20) accommodates an electrode assembly (10) through the open end and may also accommodate an electrolyte.

[0083] The battery housing (20) is electrically connected to the electrode assembly (10). The battery housing (20) is electrically connected to the second part (12) of the electrode assembly (10). In this case, the battery housing (20) has the same polarity as the second part (12).

[0084] The battery housing (20) may have a beading portion (21) and a crimping portion (22) formed on the open end side. The beading portion (21) may be located on the open end side of the electrode assembly (10). The beading portion (21) may be formed by pressing the outer circumference of the battery housing (20). More specifically, the beading portion (21) may have a shape that is pressed inward in the area between the open end formed on one side of the battery housing (20) and the receiving portion that accommodates the electrode assembly (10). The crimping portion (22) may be formed below the beading portion (21). The crimping portion (22) may extend from the lower beading portion (21). The above-mentioned clamping portion (22) may have an extended and bent shape to wrap around the outer surface of the lead (30) positioned below the beading portion (21) and a part of the lower surface of the lead (30). The above-mentioned clamping portion (22) may also secure a sealing gasket (90) in addition to the lead (30). However, the present invention does not exclude cases where the battery housing (20) is not equipped with such a beading portion (21) and / or a clamping portion (22). In the present invention, if the housing (20) does not have a beading portion (21) and / or a clamping portion (22), the fixing of the electrode assembly (10) and / or the fixing of the lead (30) and / or the sealing of the housing (20) can be realized, for example, through the additional application of a part that can function as a stopper for the electrode assembly (10) and / or the additional application of a structure on which the lead (30) can be seated and / or welding between the housing (20) and the lead (30).

[0085]

[0086] <Electrode Terminal>

[0087] The electrode terminal (40) is provided by passing through the through hole so as not to come into contact with the inner wall of the through hole formed in the bottom part of the battery housing (20). The electrode terminal (40) may be made of a conductive metal material. For example, aluminum (Al) may be used as the material of the electrode terminal (40).

[0088] In one embodiment of the present invention, the electrode terminal (40) is electrically connected, for example, to a first part (11) of an electrode assembly (10). In this case, the electrode terminal (40) has a first polarity. Accordingly, the electrode terminal (40) can function as a first electrode terminal in the battery cell (1) of the present invention. When the electrode terminal (40) has such a first polarity, the electrode terminal (40) is electrically insulated from the battery housing (20) having a second polarity. In the present invention, insulation can be achieved by interposing a terminal gasket (50), as described below, between the electrode terminal (40) and the battery housing (20).

[0089] In one embodiment of the present invention, when the battery cell (1) of the present invention further comprises a first current collector (60), the electrical connection portion of the terminal insertion portion may be coupled with the first current collector (60). When the battery cell (1) of the present invention does not comprise the first current collector (60), it may be coupled with the non-circulating portion of the first electrode, i.e., the first portion (11).

[0090] The electrical connection portion of the terminal insertion portion may have, for example, a roughly cylindrical shape. Of course, the shape of the electrical connection portion of the terminal insertion portion is not limited thereto. The electrical connection portion of the terminal insertion portion may have various shapes, such as a cylindrical shape with an elliptical cross-section, a square prism shape, a hexagonal prism shape, or an octagonal prism shape. The bottom surface of the electrical connection portion of the terminal insertion portion may be formed to be at least partially roughly flat. The connection between the bottom surface of the central region of the terminal insertion portion and the first current collector (60) may be achieved, for example, by laser welding, spot welding, or ultrasonic welding.

[0091] In the present invention, the outer surface of the bottom portion of the battery housing (20) and the upper surface of the terminal exposure portion exposed to the outside of the battery housing (20) among the electrode terminals (40) may have opposite polarities and face in the same direction.

[0092]

[0093] Terminal Gasket

[0094] In one embodiment of the present invention, the battery cell (1) of the present invention may further include a terminal gasket (50). The terminal gasket (50) is interposed between the battery housing (20) and the electrode terminal (40) to prevent the battery housing (20) and the electrode terminal (40), which have opposite polarities, from coming into contact with each other. Thus, the upper surface of the battery housing (20), which has a roughly flat shape, can function as a second electrode terminal of the battery cell (1). For example, among the total upper surface area of ​​the battery housing (20) viewed from the top of the cylindrical battery cell (1), the entire remaining area excluding the area occupied by the electrode terminal (40) and the terminal gasket (50) may correspond to a second electrode terminal having opposite polarity to the electrode terminal (40).

[0095]

[0096] Insulator

[0097] The battery cell (1) of the present invention includes an insulator (70) interposed between the bottom portion of the battery housing (20) and the electrode assembly (10), and is characterized in that a gas adsorption layer (73) is formed on at least one surface of the insulator (70).

[0098] In one embodiment of the present invention, when the battery cell (1) includes a first current collector (60), the first current collector (60) is located on a first portion (11) corresponding to a first unoccupied portion of the electrode assembly (10), and the insulator (70) may be interposed between the bottom portion of the battery housing (20) and the first current collector (60).

[0099] In one embodiment of the present invention, the insulator (70) basically prevents contact between the first part (11) and the battery housing (20) or contact between the first current collector (60) and the battery housing (20).

[0100] In one embodiment of the present invention, the insulator (70) may also be interposed between the upper outer surface of the electrode assembly (10) and the inner surface of the side wall of the battery housing (20). That is, the insulator (70) may also be interposed between the first part (11) and the side wall of the battery housing (20). The first current collector (60) may be a plate that extends completely across the upper outer surface of the electrode assembly (10). However, the present invention is not limited thereto, and the first current collector (60) may be formed to extend only partially across the upper outer surface of the electrode assembly (10).

[0101] In one embodiment of the present invention, the insulator (70) may have a shape corresponding to the radial cross-sectional shape of the jelly-roll type electrode assembly (10) as shown in FIG. 4. That is, it may be a shape designed to fit the radial cross-sectional shape of the electrode assembly so that it can be in close contact with or seated on the electrode assembly. For example, if the radial cross-sectional shape of the electrode assembly (10) is circular or elliptical, the insulator (70) may have a roughly circular or elliptical shape with a hollow space formed in the center. In this case, the hollow space in the center of the insulator (70) may be referred to as an insulator hole (71). Due to the presence of the insulator hole, the electrode terminal (40) may be in a state where it can come into contact with the first current collector (60) or the first part (11). Preferably, the insulator hole (71) may have a diameter that can expose the lower part of the electrode terminal (40).

[0102] In one embodiment of the present invention, the insulator (70) may include at least one electrolyte hole (72) as shown in FIG. 4. The electrolyte injected into the battery housing (20) may move through the electrolyte hole.

[0103] In one embodiment of the present invention, the electrolyte holes (72) may be spaced apart at predetermined intervals. For example, as shown in FIG. 4, a plurality of electrolyte holes (72) may be arranged along a straight line extending radially from the center of the insulator (70), i.e., the insulator hole (71). However, the number, shape, and / or arrangement of the electrolyte holes (72) as shown in FIG. 4 are not limited thereto.

[0104] In one embodiment of the present invention, the insulator (70) may include an electrical insulating polymer material to have electrical insulating properties.

[0105] In one embodiment of the present invention, the insulator (70) may include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polypropylene (PP), or a blend of two or more of these as an electrical insulating polymer material.

[0106] In one embodiment of the present invention, the insulator (70) may include a heat-resistant additive, a flame retardant, or both within the electrical insulating polymer material to increase flame retardancy. For example, the heat-resistant additive may include mica or glass fiber.

[0107]

[0108] As described above, the insulator (70) of the present invention has a gas adsorption layer (73) formed on at least one surface. For example, the insulator (70) may have a gas adsorption layer (73) formed on one surface or a gas adsorption layer (73) formed on both surfaces.

[0109] In one embodiment of the present invention, when a gas adsorption layer (73) is formed on one side of the insulator (70), the gas adsorption layer (73) may be formed on the other side of the insulator (70) that faces the battery housing (20). In this case, the physical distance between the gas adsorption layer (73) and the electrode assembly (10) is reduced, so the amount of gas adsorbed or collected may be further increased.

[0110] In one embodiment of the present invention, the gas adsorption layer (73) may include gas adsorption particles.

[0111] In one embodiment of the present invention, the gas adsorption layer (73) may further include a binder polymer. That is, the gas adsorption layer (73) may include gas adsorption particles and a binder polymer. In this case, the binder polymer may serve to bind the gas adsorption layer (73) and the insulator (70) or bind the gas adsorption particles together.

[0112] In one embodiment of the present invention, the gas adsorption particles may specifically be methane gas adsorption particles. During the cycle, the battery cell (1) of the present invention may generate hydrogen, carbon monoxide, carbon dioxide, methane, ethene, ethene, ethane, pentene, and pentane gases, and among them, methane gas may account for 90 volume% or more. Therefore, if the gas adsorption particles have excellent adsorption capacity for methane gas, the effect of preventing battery cell degradation may be even better.

[0113] In one embodiment of the present invention, the gas adsorption particles are not limited in type as long as they can remove gas physically, such as by trapping gas inside the particles, or remove gas by chemically reacting with it. For example, the gas adsorption particles may include activated carbon, aerogel, metal-organic framework (MOF), zeolite, carbon nanotube (CNT), graphene oxide, silica gel, or a combination thereof.

[0114] In one embodiment of the present invention, the binder polymer is not limited in type as long as it serves to bind the gas adsorption layer (73) and the insulator (70) or to bind between the gas adsorption particles.

[0115] In one embodiment of the present invention, the binder polymer is, for example, polyvinylidene fluoride, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polybutylacrylate, polybutylmethacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, and cellulose acetate butylate It may be cellulose acetate butyrate, cellulose acetate propionate, cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, or may contain two or more of these.

[0116] In one embodiment of the present invention, the coating amount of the gas adsorption layer (73) is 0.1 g / m² 2 Up to 1.0 g / m² 2 , 0.2 g / m2 Up to 0.8 g / m² 2 , 0.4 g / m 2 Up to 0.6 g / m² 2 or 0.4 g / m² 2 Up to 0.5 g / m² 2 It may be within the range. In this case, the amount of gas adsorption generated within the battery cell (1) may be excellent, and the energy density of the battery cell may be excellent.

[0117] In one embodiment of the present invention, the gas adsorption layer (73) may be coated at a ratio of 50% to 95% based on 100% of one surface of the insulator (70).

[0118] Meanwhile, in one embodiment of the present invention, the insulator (70) may have an uncoated portion formed on its outer circumference in the circumferential direction. That is, the gas adsorption layer (73) may not be coated on the outer circumference of the insulator (70). In this case, the electrical insulation between the inner surface of the side wall of the battery housing (20) and the electrode assembly is further improved, and unexpected side reactions of the gas adsorption particles can be prevented.

[0119] In one embodiment of the present invention, the insulator (70) may include an insulator hole (71) in the center, and an uncoated portion may be formed on the outer periphery of the insulator hole (71). In this case, contact between the electrode terminal (40) and the gas adsorption particle is prevented, thereby preventing unexpected side reactions.

[0120] In one embodiment of the present invention, the insulator (70) may include at least one electrolyte hole (72), and the periphery of the electrolyte hole (72) may have an uncoated portion formed therein. In this case, a passage for the electrolyte is secured, so the impregnation of the electrolyte into the electrode assembly may be even better.

[0121] Meanwhile, in one embodiment of the present invention, the insulator (70) may be coupled to the battery housing (20) in various ways. As one embodiment, the insulator (70) may be coupled to the battery housing (20) by a press fit before the electrode assembly (10) is housed in the battery housing (20). Alternatively, in one embodiment of the present invention, a heat-fusion layer may be formed on the insulator (70) so that the insulator (70) is fixed to the battery housing (20) by heat fusion. That is, before the electrode assembly (10) is housed in the battery housing (20), the insulator (70) may be fixed by heat fusion by hot air injection or heating after being inserted into the battery housing (20).

[0122] In one embodiment of the present invention, the insulator (70) may have a thickness of 0.8 mm to 1.6 mm or 1.0 mm to 1.4 mm. If the insulator (70) is too thin, the insulation performance may be reduced, and if the insulator (70) is too thick, it may occupy a large amount of space inside the battery housing (20), thereby reducing the capacity of the battery cell and increasing the cost. However, the thickness of the insulator (70) is not limited thereto.

[0123]

[0124] <Additional Components>

[0125] In one embodiment of the present invention, the battery cell (1) may further include an insulating tape attached to the outer surface of the electrode assembly (10) up to a point corresponding to the edge of the insulator (70). The insulating tape may be a double-sided tape or a single-sided tape. Furthermore, the present invention is not limited to insulating tape, and a heat shrink tube may be attached to the outer surface of the electrode assembly (10).

[0126] In one embodiment of the present invention, the battery cell (1) may additionally include a lead (30) and / or a first current collector (60) and / or a second current collector (80) and / or a sealing gasket (90) in addition to the components described above.

[0127] Referring to FIG. 2, the lead (30) may be made of, for example, a metal material to ensure rigidity. The lead (30) seals an open end formed on one side of the battery housing (20). That is, the lead (30) may form the lower surface of the battery cell (1). In the battery cell (1) of the present invention, even if the lead (30) is made of a conductive metal material, it may not have polarity. Not having polarity means that the lead (30) is not electrically connected to the electrode assembly (10). In this case, when the lead (30) is not electrically connected to the electrode assembly (10), the lead (30) does not function as a positive terminal or a negative terminal. That is, in the present invention, the lead (30) does not need to be electrically connected to the electrode assembly (10) and the housing (20), and its material does not necessarily have to be a conductive metal.

[0128] According to FIG. 2, the first current collector (60) may be placed on the upper part of the electrode assembly (10), and the first current collector (60) may be coupled to the electrode terminal (40). That is, the first current collector (60) may be configured to electrically connect the first part (11) of the electrode assembly (10) and the electrode terminal (40). The first current collector (60) is made of a conductive metal material and may be connected to the first part (11), which is a non-conductive part.

[0129] The first current collector (60) may be joined to the end of the first part (11). The joining between the first part (11) and the first current collector (60) may be achieved, for example, by laser welding. The laser welding may be performed by partially melting the base material of the first current collector (60), or by interposing solder for welding between the first current collector (60) and the first part (11). In this case, it is preferable that the solder has a lower melting point compared to the first current collector (60) and the first part (11).

[0130] Referring to FIG. 2, the second current collector (80) may be disposed at the bottom of the electrode assembly (10), and the second current collector (80) may be configured to electrically connect the second part (12) of the electrode assembly (10) and the battery housing (20). The second current collector (80) may be made of a conductive metal material and may be electrically connected to the second part (12).

[0131] The second current collector (80) may be joined to the end of the second part (12). The joining between the second part (12) and the second current collector (80) may be achieved, for example, by laser welding. The laser welding may be performed by partially melting the base material of the second current collector (80), or by interposing solder for welding between the second current collector (80) and the second part (12). In this case, it is preferable that the solder has a lower melting point compared to the second current collector (80) and the second part (12).

[0132] Referring to FIG. 2, the sealing gasket (90) may be interposed between a fixing structure provided on the opening side of the battery housing (20) and a lead (30) to ensure airtightness of the battery housing (20).

[0133]

[0134] The battery cell (1) according to the above-described embodiment can be used to manufacture a battery pack (100). That is, the battery pack (100) of the present invention includes the above-described battery cell (1).

[0135] FIG. 6 is a schematic diagram showing the configuration of a battery pack (100) according to an embodiment of the present invention.

[0136] Referring to FIG. 6, a battery pack (100) according to an embodiment of the present invention may include an assembly of electrically connected cylindrical batteries (101) and a pack housing (102) that accommodates the same. The cylindrical batteries (101) are battery cells (1) according to the above-described embodiment. In the drawings, for convenience of drawing, components such as busbars, cooling units, and external terminals for electrically connecting the cylindrical batteries (101) are omitted.

[0137] The battery pack (100) can be mounted on a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle includes a four-wheeled vehicle or a two-wheeled vehicle.

[0138] FIG. 7 is a drawing for explaining a vehicle including the battery pack (100) of FIG. 6.

[0139] Referring to FIG. 7, a vehicle (V) according to one embodiment of the present invention includes a battery pack (100) according to one embodiment of the present invention. The vehicle (V) operates by receiving power from the battery pack (100) according to one embodiment of the present invention.

[0140] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0141]

[0142] The present invention will be described in more detail below through examples, but the following examples are intended to illustrate the invention and the scope of the invention is not limited thereto.

[0143]

[0144] [Explanation of the symbol]

[0145] 1: Battery cell, 10: Electrode assembly, 11: First part, 12: Second part, 20: Battery housing, 21: Beading part, 22: Clamping part, 30: Lead, 40: Electrode terminal, 50: Terminal gasket, 60: First current collector, 70: Insulator, 71: Insulator hole, 72: Electrolyte hole, 73: Gas adsorption layer, 80: Second current collector, 90: Sealing gasket, 100: Battery pack, 101: Cylindrical battery, 102: Pack housing

Claims

1. An electrode assembly in the form of a jelly-roll, wherein a first electrode and a second electrode and a separator interposed between them are wound in one direction; A battery housing that accommodates the electrode assembly through a side wall portion, a bottom portion connected to one end of the side wall portion in the direction of the winding axis, and an open end formed at the other end of the side wall portion in the direction of the winding axis, and is electrically connected to a second electrode; An electrode terminal provided through a through hole formed in the bottom portion of the battery housing and electrically connected to the first electrode; and It includes an insulator interposed between the bottom portion of the battery housing and the electrode assembly; A battery cell characterized by having a gas adsorption layer formed on at least one surface of the above-mentioned insulator.

2. In Claim 1, A battery cell characterized in that the above gas adsorption layer includes gas adsorption particles.

3. In Claim 2, A battery cell characterized in that the above gas adsorption layer further comprises a binder polymer.

4. In Claim 2, A battery cell characterized in that the above gas adsorption particles comprise activated carbon, aerogel, metal-organic framework (MOF), zeolite, carbon nanotube (CNT), graphene oxide, silica gel, or a combination thereof.

5. In Claim 3, The above binder polymer is polyvinylidene fluoride, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polybutylacrylate, polybutylmethacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyethylene-co-vinyl acetate copolymer, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose A battery cell characterized by comprising acetate propionate (cellulose acetate propionate), cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, or two or more of these.

6. In Claim 1, A battery cell characterized in that the gas adsorption layer is formed on the other side of the surface facing the battery housing.

7. In Claim 1, The coating amount of the above gas adsorption layer is 0.1 g / m² 2 Up to 1.0 g / m² 2 A battery cell characterized by being within the range of 8. In Claim 1, A battery cell characterized by the above gas adsorption layer being coated at a ratio of 50% to 95% based on 100% of one side of the insulator.

9. In Claim 1, A battery cell characterized in that the insulator has a shape corresponding to the radial cross-sectional shape of the jelly-roll type electrode assembly.

10. In Claim 1, A battery cell characterized in that the above-mentioned insulator has an uncoated portion formed on the outer periphery in the circumferential direction.

11. In Claim 1, The above insulator includes an insulator hole in the center, and A battery cell characterized by having an uncoated portion formed on the outer periphery of the insulator hole in the circumferential direction.

12. In Claim 1, A battery cell characterized in that the above-described insulator includes at least one electrolyte hole.

13. A battery pack comprising a battery cell according to any one of claims 1 to 12.

14. An automobile comprising the battery pack of claim 13.

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