Cylindrical battery cell, battery pack and vehicle comprising same, and collector plate

Abstract

Disclosed are a cylindrical battery cell, a battery pack and a vehicle including the same, and a collector plate. A cylindrical battery cell according to one embodiment of the present invention comprises: an electrode assembly configured such that a positive plate, a negative plate, and a separator interposed between the positive plate and the negative plate are wound in one direction; a cylindrical battery can accommodating the electrode assembly therein and having a through hole; a positive electrode collector plate electrically connected to the positive electrode plate; the battery core terminal penetrates through the through hole of the battery can and is connected to the positive electrode collector plate; and a negative electrode collector plate electrically connected to the negative electrode plate, in which the positive electrode collector plate or the negative electrode collector plate has a fracture inducing portion such that at least a part of the positive electrode collector plate or the negative electrode collector plate is fractured by a gas generated inside the battery can.

Description

Technical Field

[0001] This application claims priority from Korean Patent Application No. 10-2023-0099233 filed in Korea on July 28, 2023, the disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to a cylindrical battery cell, a battery pack and a vehicle including the cylindrical battery cell, and a current collector plate, and more particularly, to a cylindrical battery cell capable of reducing the internal pressure of the cylindrical battery cell, a battery pack and a vehicle including the cylindrical battery cell, and a current collector plate. Background Art

[0003] Secondary batteries are easily applicable according to product groups and have electrical characteristics such as high energy density, and are generally used in electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by an electric drive source, and portable devices.

[0004] These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency due to a major advantage of drastically reducing the use of fossil fuels and another advantage of not generating byproducts due to energy use.

[0005] Currently, widely used secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, etc. The operating voltage of the unit secondary battery cell is about 2.5V to 4.5V.

[0006] Therefore, when an output voltage higher than the operating voltage is required, a battery pack can be configured by connecting multiple battery cells in series. Furthermore, a battery module or battery pack can be configured by connecting multiple battery cells in parallel according to the required charge / discharge capacity. Therefore, the number of battery cells included in a battery pack and the type of electrical connection thereof can be set in various ways depending on at least one of the required output voltage or charge / discharge capacity.

[0007] Meanwhile, as types of secondary battery cells, cylindrical, square, and pouch-type battery cells are known. In the case of cylindrical battery cells, a separator, serving as an insulator, is interposed between the positive and negative electrode plates, which are wound to form a jellyroll-type electrode assembly, which is then inserted into a battery can along with an electrolyte to form a battery. In addition, a current collector plate may be used to electrically connect each of the positive and negative electrode plates in the cylindrical battery cell.

[0008] Repeated charge and discharge cycles of cylindrical battery cells may generate gas inside the electrode assembly, thereby increasing internal pressure, which may cause an explosion if the internal pressure is not reduced, so vent portions may be formed in cylindrical battery cells in various ways.

[0009] However, conventional cylindrical battery cells have a problem in that gas discharge is not easy because the current collector plate blocks the space between the central portion and the vent portion of the electrode assembly. Summary of the Invention

[0010] Technical issues

[0011] The present disclosure is designed to solve the problems of the related art, and thus the present disclosure aims to provide a cylindrical battery cell, a battery pack and a vehicle including the cylindrical battery cell, and a collector plate, in which the shape of the collector plate is deformed due to the internal pressure increased when gas is generated inside the cylindrical battery cell, thereby reducing the internal pressure and preventing explosion.

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

[0013] Technical Solution

[0014] According to one aspect of the present disclosure, a cylindrical battery cell is provided, which includes: an electrode assembly, which is configured as a structure in which a positive plate, a negative plate, and a separator inserted between the positive plate and the negative plate are wound in one direction; a cylindrical battery can, which is configured to store the electrode assembly and has a through hole formed thereon; a positive collector plate, which is electrically connected to the positive plate; a cell terminal, which is connected to the positive collector plate through the through hole of the battery can; and a negative collector plate, which is electrically connected to the negative plate, wherein a fracture inducing portion is formed on the positive collector plate or the negative collector plate, so that at least a portion of the positive collector plate or the negative collector plate is fractured by gas generated inside the battery can.

[0015] In one embodiment, the positive electrode collector plate or the negative electrode collector plate may include: an edge portion defining an edge; a central portion spaced apart from the edge portion and coupled to the electrode assembly; and a connecting portion configured to connect the edge portion and the central portion.

[0016] In one embodiment, the breakage inducing portion may be formed in the connecting portion.

[0017] In one embodiment, the fracture inducing portion may be formed in the connecting portion at a position where the central portion and the connecting portion meet.

[0018] In one embodiment, the fracture inducing portion may be formed as a notch groove.

[0019] In one embodiment, the fracture inducing portion may be formed as a through hole.

[0020] In one embodiment, four connection portions may be provided, and eight notch grooves may be provided such that a pair of notch grooves are formed in each connection portion.

[0021] In one embodiment, the notch groove may be formed to be recessed toward the inside of the connecting portion in a direction in which the width or thickness of the connecting portion gradually or continuously decreases.

[0022] In one embodiment, the fracture inducing portion may be configured to include a twisted portion formed by twisting the connecting portion.

[0023] In one embodiment, the twisting portion may include a first portion connected to the central portion; and a second portion configured to be twisted and folded from the first portion and then joined to the edge portion.

[0024] In one embodiment, the twisting portion may be formed in a curved shape to rotate the gas.

[0025] In one embodiment, the twisting portion may be configured such that the connecting portion is rotated 180 degrees from the central portion and coupled to the edge portion.

[0026] Meanwhile, according to another aspect of the present disclosure, a battery pack including at least one of the above-mentioned cylindrical battery cells may be provided, and a vehicle including at least one of the above-mentioned cylindrical battery cells may be provided.

[0027] At the same time, according to another aspect of the present disclosure, a collector plate can be provided, which is electrically connected to the electrode assembly and is located at a portion of the cylindrical battery cell where a vent portion is formed, the collector plate comprising: an edge portion defining an edge; a central portion, which is spaced apart from the edge portion and connected to the electrode assembly; and a connecting portion configured to connect the edge portion and the central portion, wherein a fracture inducing portion is formed on the collector plate so that at least a portion of the collector plate is fractured by the gas generated inside the cylindrical battery cell.

[0028] Beneficial effects

[0029] The embodiment of the present disclosure has an effect of reducing the internal pressure by deforming the shape of the collector plate when gas is generated inside the cylindrical battery cell to increase the internal pressure.

[0030] In addition, it also has the effect of preventing the explosion of cylindrical battery cells.

[0031] However, effects obtainable by the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned above will be clearly understood by those skilled in the art through the description of the present invention described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the detailed description of the present disclosure, serve to provide further understanding of the technical concept of the present disclosure. Therefore, the present disclosure is not to be construed as being limited to the accompanying drawings.

[0033] Figure 1 is a perspective view of a cylindrical battery cell according to one embodiment of the present disclosure.

[0034] Figure 2 is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present disclosure.

[0035] Figure 3 is a diagram illustrating a battery can in a cylindrical battery cell according to one embodiment of the present disclosure.

[0036] Figure 4 is a perspective view of a negative electrode collector plate of a cylindrical battery cell according to one embodiment of the present disclosure.

[0037] Figures 5 to 10 According to Figure 4 A perspective view of a negative electrode current collector plate according to a modification of the embodiment.

[0038] Figure 11 It shows that the shape has changed Figure 10 A three-dimensional diagram of the negative electrode collector plate.

[0039] Figure 12 is a diagram schematically illustrating a configuration of a battery pack including cylindrical battery cells according to each embodiment of the present disclosure.

[0040] Figure 13 is a diagram illustrating a vehicle including a battery pack according to each embodiment of the present disclosure. DETAILED DESCRIPTION

[0041] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be understood that the terms used in the specification and the appended claims should not be interpreted as limited to general meanings and dictionary meanings, but should be interpreted according to the meanings and concepts corresponding to the technical aspects of the present disclosure based on the principle of allowing the inventor to appropriately define the terms for the best interpretation. Therefore, the configurations proposed in the embodiments of this specification and the drawings only represent the most preferred embodiments of the present disclosure and do not represent all technical concepts of the present disclosure. Therefore, it should be understood that various equivalents and modifications may be made to them when filing an application.

[0042] For the purpose of illustration and clarification, the dimensions of the various elements or specific parts of each element shown in the drawings are exaggerated, omitted, or simplified. Therefore, the dimensions of the various elements do not fully reflect their actual dimensions. Descriptions of related known functions or configurations that may obscure the subject matter of this disclosure will be omitted.

[0043] The expression “one element is “coupled” or “fastened” to another element” should be understood that the elements may be directly coupled or fastened to each other, and the elements may be indirectly coupled or fastened to each other through another element.

[0044] Figure 1 is a perspective view of a cylindrical battery cell according to one embodiment of the present disclosure, Figure 2 is a cross-sectional view of a cylindrical battery cell according to one embodiment of the present disclosure, Figure 3 is a diagram showing a battery can in a cylindrical battery cell according to one embodiment of the present disclosure, and Figure 4 is a perspective view of a negative electrode collector plate of a cylindrical battery cell according to one embodiment of the present disclosure.

[0045] Reference Figure 1 and Figure 2 A cylindrical battery cell 10 according to one embodiment of the present disclosure includes an electrode assembly 100 , a battery can 200 , a positive electrode collector plate 300 , a cell terminal 400 , and a negative electrode collector plate 600 .

[0046] Reference Figure 2 The electrode assembly 100 has a structure in which a positive electrode plate 110, a negative electrode plate 120, and a separator 130 interposed between the positive electrode plate 110 and the negative electrode plate 120 are wound in one direction. In addition, a central hole 140 may be formed at the center of the electrode assembly 100 to configure a core-wound type.

[0047] For example, the electrode assembly 100 may be manufactured by winding a stack obtained by sequentially stacking the negative electrode plate 120, the separator 130, the positive electrode plate 110, and the separator 130 at least once. Here, the positive electrode plate 110 and the negative electrode plate 120 may be formed in a sheet shape.

[0048] That is, the electrode assembly 100 applied to this embodiment may be a wound type electrode assembly 100. In this case, an additional separator may be provided on the outer surface of the electrode assembly 100 for insulation from the battery can 200. That is, the electrode assembly 100 may have a wound structure known in the related art without limitation.

[0049] The positive electrode plate 110 may have a positive electrode active material applied on one or both sides thereof, and a first non-coating portion 111 (see FIG. 1 ) on which no positive electrode active material is applied. Figure 2 ) may be formed at the end of the positive electrode plate 110. Although Figure 2 The positive electrode plate 110 is shown with the first uncoated portion 111 formed thereon, but the cylindrical battery cell 10 according to one embodiment of the present disclosure includes an embodiment of the positive electrode plate 110 without the first uncoated portion 111 formed thereon. However, for ease of explanation, the following description will be based on the positive electrode plate 110 with the first uncoated portion 111 formed thereon. The first uncoated portion 111 may be exposed to the outside of the separator 130 while forming a plurality of winding turns around the center of the electrode assembly 100, and may itself serve as an electrode tab.

[0050] The negative electrode plate 120 may have a negative electrode active material applied to one or both sides thereof, and a second non-coating portion 121 (see FIG. 1 ) on which no negative electrode active material is applied. Figure 2 ) may be formed at the end of the negative electrode plate 120. Although Figure 2 The negative electrode plate 120 is shown with the second uncoated portion 121 formed thereon, but the cylindrical battery cell 10 according to one embodiment of the present disclosure includes an embodiment of the negative electrode plate 120 without the second uncoated portion 121 formed thereon. However, for ease of explanation, the following description will be based on the negative electrode plate 120 with the second uncoated portion 121 formed thereon. The second uncoated portion 121 can be exposed to the outside of the separator 130 while forming a plurality of winding turns around the center of the electrode assembly 100, and can itself serve as an electrode tab.

[0051] That is, at least one of the positive electrode plate 110 and the negative electrode plate 120 may include an uncoated portion at a long side end along the winding direction where the active material is not coated. In addition, the first uncoated portion 111 and the second uncoated portion 121 may be configured to point in opposite directions to each other.

[0052] Here, any active material known in the art may be used for the positive electrode active material coated on the positive electrode plate 110 and the negative electrode active material coated on the negative electrode plate 120 without limitation.

[0053] In addition, the separator 130 can be configured as a single porous polymer film, for example, a porous polymer film made of a polyolefin polymer (such as ethylene homopolymer, propylene homopolymer, ethylene / butene copolymer, ethylene / hexene copolymer, ethylene-methacrylate copolymer, etc.) or a stack thereof.

[0054] As another example, a conventional porous non-woven fabric, such as a non-woven fabric made of high-melting-point glass fiber, polyethylene terephthalate fiber, etc., may be used for the separator 130 .

[0055] The separator 130 may include a coating of inorganic particles on at least one surface thereof. In addition, the separator 130 itself may be formed of a coating of inorganic particles. The particles constituting the coating may have a structure in which they are bonded with a binder so that there is a gap volume between adjacent particles.

[0056] Furthermore, the central hole 140 of the electrode assembly 100 is also used to weld the cell terminal 400 (positive terminal) and the positive collector plate 300 . That is, laser light can be irradiated through the central hole 140 of the electrode assembly 100 , thereby welding the cell terminal 400 and the positive collector plate 300 .

[0057] Reference Figure 2 , the electrode assembly 100 is received inside the battery can 200. In addition, referring to Figure 3 , a through hole 211 is formed in the battery can 200. For example, the battery can 200 may be formed in a cylindrical shape so that the electrode assembly 100 is accommodated inside the battery can 200 and may be electrically connected to the negative electrode plate 120 of the electrode assembly 100. Therefore, the battery can 200 may have the same polarity as the negative electrode plate 120, that is, a negative polarity.

[0058] Here, the diameter of the battery can 200 is formed to be larger than the diameter of the electrode assembly 100. A gap of a preset size may be formed between the battery can 200 and the positive electrode collector plate 300, and the insulator 500 may be disposed in the gap.

[0059] If the size of the electrode assembly 100 increases in a state in which the size of the battery can 200 is fixed according to a standard, the total capacity of the battery cell increases, but the gap between the battery can 200 and the electrode assembly 100 decreases.

[0060] That is, since the gap between the battery can 200 and the electrode assembly 100 is reduced if the size of the electrode assembly 100 is increased to increase the total capacity of the battery cell, the insulator 500 must be provided in the reduced gap between the battery can 200 and the electrode assembly 100. For this reason, in order to increase the capacity of the battery cell, the thickness of the insulator 500 is expected to be as thin as possible.

[0061] Reference Figure 3, the battery can 200 may have a closing portion 210 and an opening 220 positioned opposite to each other.

[0062] For example, in Figure 3 In the embodiment, the opening 220 may be formed at the bottom of the battery can 200. The battery can 200 receives the electrode assembly 100 through the opening 220 formed at the bottom, and the electrolyte is also injected through the opening 220 formed at the bottom of the battery can 200.

[0063] That is, the battery can 200 is a substantially cylindrical container having an opening 220 formed at the bottom thereof and may be made of a conductive material such as metal. The battery can 200 may be made of a conductive metal such as aluminum, steel, stainless steel, etc., but is not limited thereto.

[0064] In addition, Figure 3 In the embodiment, the closing portion 210 may be formed in the upper portion of the battery can 200. The closing portion 210 may be partially formed on the opposite side of the opening 220. A through hole 211 is formed in the closing portion 210, and as shown in FIG. Figure 2 As shown, the cell terminal 400 is coupled to the through hole 211 and is electrically connected to the positive electrode collector plate 300 through the through hole 211. Figure 2 , the insulator 500 may be interposed between the battery can 200 and the positive electrode collector plate 300 on one side of the closing portion 210 .

[0065] The positive electrode collector plate 300 is electrically connected to the positive electrode plate 110 and, for example, refers to Figure 2 , positive electrode collector plate 300 is connected to positive electrode plate 110 in the upper portion of electrode assembly 100. Here, fracture induction portion 700 may be formed in positive electrode collector plate 300. As will be described in detail below, the present disclosure will be described based on the case where fracture induction portion 700 is formed in negative electrode collector plate 600, and the description of negative electrode collector plate 600 can also be applied to the case where fracture induction portion 700 is formed in positive electrode collector plate 300.

[0066] The positive electrode collector plate 300 is made of a conductive metal and is connected to the first uncoated portion 111 of the electrode assembly 100. The positive electrode collector plate 300 may be coupled to the top of a coupling surface formed by bending the end of the first uncoated portion 111 in a direction parallel to the positive electrode collector plate 300. The bending direction of the first uncoated portion 111 may be, for example, toward the central wound portion of the electrode assembly 100.

[0067] If the first uncoated portion 111 has the above-mentioned curved shape, the space occupied by the first uncoated portion 111 can be reduced, thereby improving energy density. In addition, the coupling area between the first uncoated portion 111 and the positive electrode collector plate 300 can be increased, thereby improving bonding strength and reducing resistance.

[0068] The cell terminal 400 is made of a conductive metal and is connected to the through-hole 211 formed in the closed portion 210 of the battery can 200 so as to be electrically connected to the positive electrode collector plate 300 through the through-hole 211. In addition, the cell terminal 400 is electrically connected to the positive electrode plate 110 of the electrode assembly 100 through the positive electrode collector plate 300 and therefore has a positive polarity.

[0069] That is, the cell terminal 400 may serve as a positive terminal. In addition, as described above, the battery can 200 may be electrically connected to the negative electrode plate 120 of the electrode assembly 100 and thus have a negative polarity.

[0070] Reference Figure 2 , negative electrode collector plate 600 is electrically connected to negative electrode plate 120. Here, a fracture induction portion 700 may be formed in negative electrode collector plate 600. However, fracture induction portion 700 will be described later.

[0071] The negative electrode collector plate 600 is connected to the second uncoated portion 121 of the electrode assembly 100. The negative electrode collector plate 600 is coupled to a lower portion of the electrode assembly 100. The negative electrode collector plate 600 may be made of a conductive metal such as aluminum, steel, copper, nickel, etc., and is electrically connected to the second uncoated portion 121 of the negative electrode plate 120.

[0072] The negative electrode collector plate 600 may be electrically connected to the battery can 200 . To this end, at least a portion of an edge of the negative electrode collector plate 600 may be interposed and fixed between the inner surface of the battery can 200 and the sealing gasket 260 .

[0073] As one embodiment, at least a portion of the edge of the negative electrode collector plate 600 may be supported on the lower surface of the beaded portion 240 formed at the lower end of the battery can 200 and fixed to the beaded portion 240 by welding. In a modified embodiment, at least a portion of the edge of the negative electrode collector plate 600 may be directly welded to the inner wall surface of the battery can 200.

[0074] In addition, at least a portion of the remaining portion of the negative electrode collector plate 600 excluding the joining portion with the beading portion 240 may be coupled to the curved surface of the second non-coating portion 121 by welding (eg, laser welding).

[0075] In addition, at least a portion of the edge of the negative electrode collector plate 600 may be electrically coupled to one of the upper and lower surfaces of the beading portion 240 adjacent to the crimping portion 250 .

[0076] Reference Figure 2 The cover plate 230 is configured to seal the opening 220 formed at the bottom of the battery can 200 (see Figure 3 ). The cover plate 230 may be made of, for example, metal to ensure rigidity.

[0077] In addition, the cap plate 230 may be separated from the electrode assembly 100 so as not to have polarity. That is, even if the cap plate 230 is made of a conductive metal, it may not have polarity.

[0078] The fact that the cap plate 230 has no polarity indicates that the cap plate 230 is electrically insulated from the battery can 200 and the cell terminals 400. As described above, the cap plate 230 may have no polarity and is not necessarily made of a conductive metal.

[0079] The cover plate 230 may be placed and supported on the curling portion 240 formed in the battery can 200. Furthermore, the cover plate 230 is secured by the crimping portion 250. A sealing gasket 260 may be interposed between the cover plate 230 and the crimping portion 250 of the battery can 200 to ensure airtightness of the battery can 200. That is, the sealing gasket 260 may be configured to be interposed between the edge of the cover plate 230 and the opening 220 of the battery can 200.

[0080] A crimping portion 240 and a crimping portion 250 may be formed in a lower portion of the battery can 200 .

[0081] The beading portion 240 is formed by pressing the outer circumference of the battery can 200 inward in a region adjacent to the opening 220 of the battery can 200 .

[0082] The beading portion 240 can support the electrode assembly 100 having a size substantially corresponding to the width of the battery can 200 so that the electrode assembly 100 does not exit through the opening 220 formed at the bottom of the battery can 200, and can also serve as a support member on which the cover plate 230 is seated. In addition, the beading portion 240 can support the outer surface of the sealing gasket 260.

[0083] The crimping portion 250 is configured to extend and bend to the inside of the battery can 200 and wrap around and fix the edge of the cover plate 230 together with the sealing gasket 260. Here, based on the arrangement of the battery can 200, the crimping portion 250 is formed at the bottom of the battery can 200. For example, in Figure 2 The battery can 200 is arranged so that the cell terminals 400 are located at the top. Figure 2 , the pressing portion 250 is formed at the bottom of the battery can 200. In addition, as Figure 2 As shown, the crimping portion 250 is formed below the crimping portion 240. However, this is merely one embodiment, and the positions of the crimping portion 250 and the crimping portion 240 are not limited thereto.

[0084] In addition, the present disclosure does not exclude the case where the battery can 200 does not have at least one of the curling portion 240 and the crimping portion 250. In the present disclosure, if the battery can 200 does not have at least one of the curling portion 240 and the crimping portion 250, the fixation of the electrode assembly 100, the fixation of the cover plate 230, or the sealing of the battery can 200 may be achieved by additional application of a component that can serve as a stopper for the electrode assembly 100, additional application of a structure on which the cover plate 230 can be placed, and at least one of welding between the battery can 200 and the cover plate 230.

[0085] exist Figure 2 , the crimping portion 250 is formed below the beading portion 240. The crimping portion 250 is configured to extend and bend to surround the edge of the cover plate 230 disposed below the beading portion 240. The cover plate 230 is fixed to the beading portion 240 by the bent shape of the crimping portion 250.

[0086] At the same time, the battery can 200 of the present disclosure may not have at least one of the curling portion 240 and the crimping portion 250. In this case, the sealing gasket 260 can be inserted between the fixing structure and the cover plate 230 on the side of the opening 220 provided in the battery can 200 to ensure the airtightness of the battery can 200.

[0087] For example, the crimping portion 250 may not be included, the cover plate 230 may cover the opening 220 of the battery can 200, and another fixing structure may be used to fix the cover plate 230. For example, the unexamined Korean patent publication KR 10-2019-0030016A filed by the applicant discloses a cylindrical battery cell that does not include the crimping portion 240, and this structure may be applied to the present disclosure.

[0088] A vent notch 231 may be formed in the cap plate 230 so as to break when the pressure inside the battery can 200 exceeds a threshold value.

[0089] For example, the venting notches 231 may be formed on both sides of the cover plate 230 and may be formed in at least one of a continuous circular pattern, a discontinuous circular pattern, and a linear pattern on the surface of the cover plate 230. Furthermore, the venting notches 231 may be formed in various other patterns.

[0090] based on Figure 2 In the arrangement of the battery can 200, the venting notch 231 may be formed at the bottom of the battery can 200, and may be configured so that when the venting notch 231 is broken, the gas is discharged from the battery can 200 through the bottom of the battery can 200. Figure 2 In the case where the cell terminals 400 are located at the top of the battery can 200 , the venting notch 231 may be formed at the bottom of the battery can 200 .

[0091] The exhaust notch 231 may be formed to be thinner than a surrounding area of ​​the cover plate 230 .

[0092] Since the vent notch 231 is thinner than the surrounding area, it may be broken more easily than the surrounding area, and when the internal pressure of the battery can 200 increases to a certain level or higher, the vent notch 231 may be broken to discharge the gas generated inside the battery can 200 .

[0093] For example, the venting notch 231 may be formed by cutting grooves on one or both sides of the cover plate 230 to partially reduce the thickness of the battery can 200 .

[0094] The cylindrical battery cell 10 according to one embodiment of the present disclosure may have a configuration in which both the positive terminal and the negative terminal are located Figure 2 The structure in the upper part of the , and therefore the upper structure is more complicated than the lower structure.

[0095] Therefore, in order to smoothly discharge the gas generated inside the battery can 200 , a venting notch 231 may be formed on the cap plate 230 constituting the lower surface of the cylindrical battery cell 10 .

[0096] As described above, if the gas generated inside the battery can 200 provided in the cylindrical battery cell 10 is discharged downward, it may be beneficial to the safety of the user.

[0097] For example, if the cylindrical battery cell 10 is installed directly under the driver's seat in an electric vehicle, if gas is discharged upward, there may be a risk of a safety accident for the driver. However, if gas is discharged downward from the battery can 200 as in the cylindrical battery cell 10 according to one embodiment of the present disclosure, this problem does not occur even if the cylindrical battery cell 10 is installed directly under the driver's seat in an electric vehicle.

[0098] Hereinafter, fracture inducing portion 700 will be described. Fracture inducing portion 700 may be formed on a current collector plate disposed in the gas exhaust direction. That is, fracture inducing portion 700 may be formed on a current collector plate electrically connected to electrode assembly 100 in a region forming a vent portion in cylindrical battery cell 10.

[0099] In the present embodiment, the vent portion may be vent notch 231 formed on cap plate 230 , and in this case, fracture induction portion 700 may be formed on negative electrode collector plate 600 in the region where vent notch 231 is formed.

[0100] For example, as described above, due to the gas generated inside the battery can 200 provided in the cylindrical battery cell 10, Figure 2Since the gas is discharged downward from the cylindrical battery cell 10, the fracture induction portion 700 is formed on the negative electrode current collector plate 600 located at the bottom. In addition, although not shown in the drawings, for example, in the case where the gas is discharged through the upper portion of the cylindrical battery cell 10 and the positive electrode current collector plate 300 is provided at the top, the fracture induction portion 700 may be formed on the positive electrode current collector plate 300.

[0101] That is, the fracture induction portion 700 may be formed on the positive electrode collector plate 300 or the negative electrode collector plate 600 according to the direction of gas discharge. Figure 2 In the illustrated embodiment, since fracture inducing portion 700 is formed on negative electrode current collector plate 600, for ease of explanation, the following description will be based on the case where fracture inducing portion 700 is formed on negative electrode current collector plate 600. Furthermore, the description of the embodiment in which fracture inducing portion 700 is formed on negative electrode current collector plate 600 can also be applied to the embodiment in which fracture inducing portion 700 is formed on positive electrode current collector plate 300.

[0102] like Figure 2 As shown, the rupture induction portion 700 is formed on the negative electrode collector plate 600 and is configured to cause at least a portion of the negative electrode collector plate 600 to rupture by gas generated inside the battery can 200 .

[0103] Reference Figure 2 Since the negative electrode collector plate 600 is located between the central hole 140 of the electrode assembly 100 and the cover plate 230 , when the gas generated inside the battery can 200 moves toward the cover plate 230 through the central hole 140 , the movement is hindered by the negative electrode collector plate 60 .

[0104] That is, if the negative electrode collector plate 600 remains in its original position, the gas generated inside the battery can 200 is not easily discharged due to the interference of the negative electrode collector plate 600, thereby increasing the internal pressure of the battery can 200. However, if the internal pressure of the battery can 200 is not reduced without being processed, an explosion may occur in the cylindrical battery cell 10.

[0105] Therefore, to solve this problem, the cylindrical battery cell 10 according to one embodiment of the present disclosure is configured such that the fracture induction portion 700 is formed on the negative collector plate 600 so that the negative collector plate 60 is fractured by the internal pressure of the battery can 200 .

[0106] Reference Figure 4 , the negative electrode collector plate 600 may be configured to include an edge portion 610 , a central portion 620 , and a connection portion 630 . Figure 4 Shown from Figure 2 The negative electrode collector plate 600 is viewed from the opposite direction. Figure 2The central portion 620 is located above the edge portion 610, but Figure 4 The central portion 620 is located below the edge portion 610. Figures 5 to 11 The same is true in .

[0107] The edge portion 610 defines an edge and may have an approximately rim shape in which at least a portion of the inner area is hollow to form an inner space. Figure 4 The middle edge portion 610 is shown as not having an approximately circular rim shape, but the shape of the edge portion 610 is not limited thereto. Unlike shown, the edge portion 610 may have an approximately square rim shape, a hexagonal rim shape, an octagonal rim shape, or other shapes. The edge portion 610 may be coupled to the connection portion 630.

[0108] The central portion 620 is located inside the edge portion 610 and is spaced apart from the edge portion 610. For example, the central portion 620 may be located at the exact center of the inner space of the edge portion 610, but is not limited thereto. In addition, the central portion 620 is coupled to the connection portion 630 and is connected to the edge portion 610 via the connection portion 630. In addition, the central portion 620 is coupled to the electrode assembly 100. Here, the central portion 620 may be provided at a position corresponding to the central hole 140 of the electrode assembly 100.

[0109] The connection portion 630 connects the edge portion 610 and the central portion 620. A plurality of connection portions 630 may be provided, and the plurality of connection portions 630 may be spaced apart from each other. Figure 4 Four connection parts 630 are provided in the embodiment, but the number of the connection parts 630 is not limited thereto. In addition, the plurality of connection parts 630 may be provided at equal intervals, but are not limited thereto.

[0110] Here, the fracture inducing portion 700 may be formed at various locations and formed in, for example, the connecting portion 630. As one embodiment, as Figure 4 As shown, fracture induction portion 700 may be formed in connection portion 630 at a location where central portion 620 and connection portion 630 meet. However, fracture induction portion 700 need not be formed only at a location where central portion 620 and connection portion 630 meet, and may be formed at any location of connection portion 630.

[0111] Reference Figure 4, fracture inducing portion 700 may be formed as a groove, such as a notch groove 710, in which the width of connection portion 630 decreases at a position where central portion 620 and connection portion 630 meet. Furthermore, notch groove 710 may be formed so as to be recessed toward the interior of connection portion 630 in a direction in which the width of connection portion 630 gradually or continuously decreases (in the left-right direction of connection portion 630). That is, notch groove 710 may be formed in the width direction from the outer end of connection portion 630 toward the interior thereof. Here, the outer end of connection portion 630 is on the side of edge portion 610, and the inner end of connection portion 530 is on the side of central portion 620.

[0112] The notch groove 710 can have various shapes. Figure 4 Here, it is formed in a triangular shape, but is not limited thereto and may have various shapes.

[0113] In addition, if Figure 4 As shown, a pair of fracture inducing portions 700 may be provided to be respectively provided at both ends of the connection portion 630. For example, four connection portions 630 may be provided, and eight notch grooves 710 may be formed so that a pair of notch grooves are provided in each connection portion 630, but the present disclosure is not limited thereto.

[0114] As described above, if the fracture inducing portion 700 such as the notch groove 710 is formed in the connecting portion 630, when the internal pressure of the battery can 200 increases, the connecting portion 630 may be fractured in the notch groove 710, thereby also allowing the central portion 620 coupled to the electrode assembly 100 to be easily removed.

[0115] Furthermore, if the central portion 620 is removed and the central hole 140 of the electrode assembly 100 is opened, the gas inside the battery can 200 moves toward the cap plate 230 through the central hole 140 and breaks the vent notch 231 formed in the cap plate 230. Therefore, the gas inside the battery can 200 can be easily discharged from the battery can 200.

[0116] In addition, the internal pressure of the cylindrical battery cells 10 may be reduced by the discharge of gas inside the battery can 200 , thereby preventing the explosion of the cylindrical battery cells 10 .

[0117] Figures 5 to 10 According to Figure 4 A perspective view of a negative electrode collector plate according to a modification of the embodiment of FIG. Figure 11 It shows that the shape has changed Figure 10 A three-dimensional diagram of the negative electrode collector plate.

[0118] Regarding repeated components, Figure 4 The description of the embodiments in the Figures 5 to 11 In addition, it is applicable to Figures 5 to 11 In the variant embodiment Figure 4 The description of the embodiments in can be applied to Figures 5 to 11 A variant implementation in .

[0119] Reference Figure 5 ,and Figure 4 As in the embodiment of FIG, the fracture inducing portion 700 may be formed as a groove, such as a notch groove 710. However, in Figure 4 In the embodiment, the groove is formed so that the width (in the left-right direction) of the connecting portion 630 is reduced, while in the embodiment Figure 5 In the embodiment, the groove is formed so that the thickness (in the up-down direction) of the connecting portion 630 decreases. That is, the notch groove 710 may be formed to be recessed toward the inside of the connecting portion 630 in a direction in which the thickness of the connecting portion 630 gradually or continuously decreases.

[0120] Reference Figure 5 , the notch groove 710 may be formed on the upper and lower surfaces of the connecting portion 630 at the location where the central portion 620 and the connecting portion 630 meet. As described above, even if the notch groove 710 is formed so that the thickness of the connecting portion 630 is reduced, the connecting portion 630 may be broken in the notch groove 710 due to the internal pressure of the battery can 200.

[0121] Reference Figure 6 , fracture inducing portion 700 may be formed as a through hole 720. Here, through hole 720 may be formed in any portion of connecting portion 630. For example, through hole 720 may be formed in the middle of connecting portion 630, or may be formed in connecting portion 630 at a location where central portion 620 and connecting portion 630 meet.

[0122] Various numbers of through holes 720 may be provided. For example, although Figure 6 In the embodiment, one through hole 720 is formed in one connection portion 630 , but this is merely one embodiment, and the number of through holes 720 formed in one connection portion 630 may vary.

[0123] Furthermore, the through hole 720 may have various shapes. For example, although Figure 6 A middle circular through hole 720 is formed in the connection portion 630 , but this is merely one embodiment, and the shape of the through hole 720 may vary, such as an oval shape, a triangular shape, or a square shape.

[0124] As described above, if the through hole 720 is formed in the connection portion 630 , the connection portion 630 may be easily broken due to the internal pressure of the battery can 200 .

[0125] In addition, refer to Figure 7 , fracture inducing portion 700 is configured such that a notched groove 710 is further formed in circular through-hole 720. That is, a pair of triangular notched grooves 710 are formed outward from the outer periphery of circular through-hole 720. Here, the pair of notched grooves 710 may be formed to face in opposite directions. Here, the shapes of through-hole 720 and notched groove 710 may vary.

[0126] Reference Figure 8 , fracture inducing portion 700 may be configured to include twisted portion 730 formed by twisting connecting portion 630. Twisted portion 730 may be formed by cutting a portion of connecting portion 630 connected to edge portion 610, twisting the portion so that the opposite surface (lower surface) faces upward, and welding the portion to edge portion 410.

[0127] In addition, when the connecting portion 630 is twisted and connected to the edge portion 610, the degree of welding can be adjusted to induce cracking, thereby making it easy to break the edge portion 610 and the connecting portion 630. Here, a cutout or groove (e.g., a notch groove) can be formed at the position where the edge portion 610 and the twisted portion 730 meet to promote the breaking of the edge portion 610 and the connecting portion 630.

[0128] For example, the twisted portion 730 may be configured to include a first portion 731 and a second portion 732. The first portion 731 is connected to the central portion 620. Furthermore, the second portion 732 is twisted and folded from the first portion 731 and then joined to the edge portion 610.

[0129] As described above, if the torsion portion 730 is formed in the connection portion 630, the gas inside the battery can 200 moves and collides with the torsion portion 730 to rotate. The gas moves and rotates, energy consumption increases, and force is evenly distributed in all directions, thereby reducing the explosive force caused by the gas.

[0130] In addition, when the connection portion 630 formed with the twist portion 730 is welded to the edge portion 610, the degree of welding may be adjusted, or a cutout or groove (eg, a notch groove) may be formed to facilitate rupture of the edge portion 610 and the connection portion 630 due to gas.

[0131] Right now, Figure 8 The embodiment has the following effects: facilitating the rupture of the edge portion 610 and the connecting portion 630 provided in the negative electrode collector plate 600 to facilitate gas discharge, thereby preventing explosion due to internal pressure, and consuming the energy possessed by the gas by rotating the gas through the torsional portion 730 to distribute the force evenly, thereby reducing the explosion force caused by the gas.

[0132] Figure 9 Shown Figure 8 A variation of the embodiment in which the torsion portion 730 is formed into a curved shape to rotate the gas. The torsion portion 730 may have various curved shapes, for example, Figure 9 , the twisting portion 730 may be configured such that the connecting portion 630 is rotated 180 degrees from the central portion 620 and coupled to the edge portion 610 .

[0133] In addition, if Figure 9 As shown, the notched groove 710 may be formed in the second portion 732 of the torsion portion 730 .

[0134] and Figure 8 Compared with the implementation method, Figure 9 The embodiment of is more favorable for gas rotation. However, it can be appropriately selected as needed. Figure 8 The implementation method or Figure 9 implementation method in .

[0135] at the same time, Figure 8 The detailed description of the embodiments in the Figure 8 implementation method in .

[0136] Reference Figure 10 , the fracture inducing portion 700 is formed as a groove, such as a notch groove 710. In addition, it is formed as a groove in which the thickness (in the up-down direction) of the connecting portion 630 is reduced. However, although Figure 5 A pair of notch grooves 710 are formed on both the upper and lower surfaces of the connecting portion 630, but Figure 10 The embodiment in FIG. 6 is different in that the notch groove 710 is formed only on the upper surface of the connection portion 630 .

[0137] In such Figure 10 As shown, in the case where only the notch groove 710 is formed on the upper surface of the connecting portion 630, as shown in FIG. Figure 11 As shown, due to the gas inside the battery can 200, the negative electrode collector plate 600 moves in the opposite direction (see Figure 11 When the central portion 620 is deformed in the opposite direction as described above, the gas inside the battery can 200 is easily discharged. Here, if the gas continues to be generated after the central portion 620 is deformed in the opposite direction, the central portion 620 and the connecting portion 630 may eventually break. Figure 5 In the embodiment, the central portion 620 of the negative electrode collector plate 600 may also be as shown in FIG. Figure 10 The battery can 200 is shown deformed in opposite directions due to the gas inside the battery can 200 .

[0138] Figure 12is a diagram schematically illustrating a configuration of a battery pack including cylindrical battery cells according to each embodiment of the present disclosure.

[0139] Reference Figure 12 A battery pack 20 according to one embodiment of the present disclosure may include one or more cylindrical battery cells 10 according to the above-described embodiments of the present disclosure. In addition, the battery pack 20 may further include a battery pack case 200 for storing the cylindrical battery cells 10, and various devices for controlling the charge and discharge of the cylindrical battery cells 10, such as a BMS, a current sensor, a fuse, etc.

[0140] Figure 13 is a diagram illustrating a vehicle including a battery pack according to each embodiment of the present disclosure.

[0141] Reference Figure 13 The vehicle 30 according to the embodiment of the present disclosure may include one or more cylindrical battery cells 10 or battery packs 20 according to each of the above-described embodiments. Here, the vehicle 30 includes various vehicles designed to use electric power, such as electric vehicles or hybrid vehicles.

[0142] Although terms indicating directions such as up, down, left, and right directions are used in this specification, it is obvious to those skilled in the art that these terms are merely for convenience of explanation and may vary depending on the position of a target object or the position of an observer.

[0143] As described above, although the present disclosure has been described with reference to limited embodiments and drawings, the present disclosure is not limited thereto, and those skilled in the art to which the present disclosure pertains may make various modifications and variations within the technical concept of the present disclosure and the equivalent scope of the claims to be described below. Therefore, the embodiments disclosed above should be considered as intended to describe the embodiments of the present disclosure, rather than to limit the embodiments of the present disclosure. In other words, the true scope of the technical concept of the present disclosure is shown in the claims, and all differences within the scope equivalent to the claims should be interpreted as included in the present disclosure.

[0144] Industry Applicability

[0145] The present disclosure relates to a cylindrical battery cell, a battery pack and a vehicle including the cylindrical battery cell, and a current collector plate, and is particularly applicable to industries related to secondary batteries.

Claims

1. A cylindrical battery cell, comprising: An electrode assembly, wherein the electrode assembly is configured as a structure in which a positive electrode plate, a negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate are wound in one direction; a cylindrical battery can configured to store the electrode assembly and having a through-hole formed therein; a positive electrode current collector plate, the positive electrode current collector plate being electrically connected to the positive electrode plate; a cell terminal connected to the positive electrode collector plate through the through-hole of the battery can; and a negative electrode collector plate electrically connected to the negative electrode plate, A fracture induction portion is formed on the positive electrode collector plate or the negative electrode collector plate, so that at least a portion of the positive electrode collector plate or the negative electrode collector plate is fractured by gas generated inside the battery can.

2. The cylindrical battery cell according to claim 1, in, The positive electrode collector plate or the negative electrode collector plate comprises: an edge portion, the edge portion defining an edge; a central portion spaced apart from the edge portion and coupled to the electrode assembly; and A connecting portion is configured to connect the edge portion and the central portion.

3. The cylindrical battery cell according to claim 2, in, The breakage inducing portion is formed in the connecting portion.

4. The cylindrical battery cell according to claim 2, in, The fracture induction portion is formed in the connecting portion at a position where the central portion and the connecting portion meet.

5. The cylindrical battery cell according to claim 1, in, The fracture inducing portion is formed as a notch groove.

6. The cylindrical battery cell according to claim 1, in, The fracture induction portion is formed as a through hole.

7. The cylindrical battery cell according to claim 5, in, Set up four connection parts, and Therein, eight notch grooves are provided so that a pair of notch grooves are formed in each connecting portion.

8. The cylindrical battery cell according to claim 5, in, The notch groove is formed to be recessed toward the inside of the connection portion in a direction in which a width or a thickness of the connection portion is gradually or continuously reduced.

9. The cylindrical battery cell according to claim 2, in, The fracture inducing portion is configured to include a twisted portion formed by twisting the connecting portion.

10. The cylindrical battery cell according to claim 9, in, The torsion portion comprises: a first portion connected to the central portion; and A second portion is configured to be twisted and folded from the first portion and then joined to the edge portion.

11. The cylindrical battery cell according to claim 9, in, The twisting portion is formed in a curved shape to rotate the gas.

12. The cylindrical battery cell according to claim 11, in, The twisting portion is configured such that the connecting portion is rotated 180 degrees from the central portion and coupled to the edge portion.

13. A battery pack comprising at least one cylindrical battery cell according to any one of claims 1 to 12.

14. A vehicle comprising at least one cylindrical battery cell according to any one of claims 1 to 12.

15. A collector plate electrically connected to an electrode assembly, the collector plate being located at a portion of a cylindrical battery cell where a vent portion is formed, the collector plate comprising: an edge portion, the edge portion defining an edge; a central portion spaced apart from the edge portion and coupled to the electrode assembly; as well as a connecting portion configured to connect the edge portion and the central portion, Wherein, a fracture inducing portion is formed on the collector plate, so that at least a portion of the collector plate is fractured by the gas generated inside the cylindrical battery cell.

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