Battery cell, battery pack and vehicle including same, and positive electrode current collector plate

Abstract

Disclosed are a battery cell, a battery pack and a vehicle including same, and a positive electrode current collector plate. A battery cell according to an embodiment of the present invention comprises: an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator; a battery can accommodating the electrode assembly; a positive electrode terminal; and a positive electrode current collector plate electrically connected to the electrode assembly and the positive electrode terminal, wherein the positive electrode current collector plate has an inner groove formed in a portion with which a welding device comes into contact.

Description

Battery cell, battery pack including the same, and automobile, and positive current collector

[0001] This application is a priority application for Korean Patent Application No. 10-2025-0015781 filed on February 7, 2025, and all contents disclosed in the specification and drawings of said application are incorporated into this application by reference.

[0002] The present invention relates to a battery cell, a battery pack including the same, an automobile, and a positive current collector, and more specifically, to a battery cell capable of improving stability, a battery pack including the same, an automobile, and a positive current collector.

[0003] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product categories, are widely applied not only to portable devices but also to electric vehicles (EVs) and hybrid electric vehicles (HEVs) driven by electric power sources.

[0004] 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.

[0005] 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.

[0006] 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.

[0007] Meanwhile, cylindrical, prismatic, and pouch-type battery cells are known as types of secondary 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 jellyroll-shaped electrode assembly, which is then inserted into a battery can along with an electrolyte to constitute a battery.

[0008] Here, the cylindrical battery cell may be provided with a current collector plate electrically connected to an electrode assembly. The current collector plate may include a positive current collector plate connected to the positive plate of the electrode assembly and a negative current collector plate connected to the negative plate of the electrode assembly.

[0009] For example, the positive current collector plate can be joined to the electrode assembly in various ways, and, for example, an ultrasonic welding method can be used.

[0010] FIG. 1 is a plan view of a conventionally formed flat anode collector plate (e.g., no groove formed), and FIG. 2 is a drawing showing the appearance of a burr formed at the welded area when ultrasonic welding is performed on the anode collector plate of FIG. 1.

[0011] In FIG. 1, when the positive current collector plate (1) is joined to the electrode assembly by ultrasonic welding at the welded portion (2), excessive burr (3) is generated around the welded portion (2), and if the burr (3) detaches and enters the battery cell, there is a problem that damage such as an internal short circuit occurs in the battery cell.

[0012] Accordingly, the technical problem to be solved by the present invention is to provide a battery cell in which the occurrence of burrs at the welded area can be reduced when the positive current collector plate is joined to the electrode assembly by welding, a battery pack including the same, an automobile, and a positive current collector plate.

[0013] In addition, the invention provides a battery cell that can prevent internal short circuits and damage to the battery cell and improve stability, a battery pack including the same, an automobile, and a positive current collector.

[0014] 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.

[0015] According to one aspect of the present invention, a battery cell may be provided comprising an electrode assembly including a positive plate, a negative plate, and a separator, a battery can in which the electrode assembly is housed, a positive current collector plate electrically connected to the electrode assembly, and a positive terminal electrically connected to the positive current collector plate, wherein an inner groove is formed in the portion of the positive current collector plate that contacts a welding device.

[0016] In one embodiment, an intaglio portion is formed on the first surface of the positive current collector plate, and a relief portion is formed on the second surface of the positive current collector plate corresponding to the opposite side of the first surface, and the inner groove may be composed of an intaglio portion.

[0017] In one embodiment, the inner groove may be formed in the center of the positive current collector plate.

[0018] In one embodiment, the welding device is an ultrasonic welder including a horn, and the horn can come into contact with the inner groove.

[0019] In one embodiment, the intaglio portion may include a first portion having a first diameter; a second portion formed on the inner side of the first portion having a second diameter smaller than the first diameter of the first portion; and a third portion formed inclined from the first portion toward the second portion.

[0020] In one embodiment, the first part and the second part are formed in a circular shape, and the third part at all positions may have the same slope.

[0021] In one embodiment, the first part may be formed larger than the horn, and the horn may be configured to enter the inside of the first part.

[0022] In one embodiment, the second part may be formed smaller than the horn.

[0023] In one embodiment, the horn may come into contact with the third part.

[0024] In one embodiment, the horn may contact the third part so as to be orthogonal to the first surface of the positive current collector plate.

[0025] In one embodiment, the raised portion may be joined to the positive terminal by welding.

[0026] Meanwhile, according to another aspect of the present invention, a battery pack comprising at least one of the aforementioned battery cells may be provided, and a vehicle comprising at least one of the aforementioned battery cells may also be provided.

[0027] Meanwhile, according to another aspect of the present invention, an anode current collector is provided for electrically connecting an electrode assembly and a positive terminal in a battery cell including a battery can, wherein the anode current collector is characterized by having an inner groove formed in the portion in which a welding device contacts.

[0028] The embodiments of the present invention have the effect of reducing the occurrence of burrs at the welded area when the anode current collector plate is joined to the electrode assembly by welding.

[0029] In addition, this has the effect of preventing internal short circuits and damage to battery cells and improving stability.

[0030] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0032] FIG. 1 is a plan view of a conventional flatly formed positive current collector plate.

[0033] Figure 2 is a drawing showing the appearance of a burr formed on the welded area when ultrasonic welding is performed on the anode collector plate of Figure 1.

[0034] FIG. 3 is a cross-sectional view of a battery cell according to one embodiment of the present invention.

[0035] FIG. 4 is a perspective view taken from the upper side of a positive current collector plate included in a battery cell according to one embodiment of the present invention.

[0036] Figure 5 is a cross-sectional view taken along A-A' in Figure 4.

[0037] FIG. 6 is a perspective view taken from the lower side of a positive current collector plate included in a battery cell according to one embodiment of the present invention.

[0038] Figure 7 is an enlarged view of part B of Figure 4.

[0039] FIG. 8 is a drawing illustrating the horn of a welding device in contact with the inner groove of a positive current collector plate in a battery cell according to one embodiment of the present invention.

[0040] Figure 9 is a cross-sectional view taken along C-C' of Figure 8.

[0041] FIG. 10 is a cross-sectional view of a positive current collector plate in contact with a positive terminal in a battery cell according to one embodiment of the present invention.

[0042] FIG. 11 is an experimental image showing the degree of burr generation according to the size of the inner groove formed in the positive current collector plate of a battery cell according to one embodiment of the present invention.

[0043] FIG. 12 is a schematic diagram showing the configuration of a battery pack including a battery cell according to each embodiment of the present invention.

[0044] FIG. 13 is a drawing for explaining a vehicle including a battery pack according to each embodiment of the present invention.

[0045] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely one preferred embodiment of the present invention and do not represent all aspects of the technical spirit of the present invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0046] In the drawings, the size of each component or specific part constituting the component is exaggerated, omitted, or schematically depicted for convenience and clarity of explanation. Accordingly, the size of each component does not entirely reflect its actual size. If it is determined that a detailed description of related known functions or configurations could unnecessarily obscure the essence of the invention, such description shall be omitted.

[0047] As used in this specification, the terms "combination" or "connection" include not only cases where one member and another member are directly joined or directly connected, but also cases where one member is indirectly joined or indirectly connected to another member through a connecting member.

[0048] Meanwhile, contents common to parts described in any one embodiment of the present invention may also be applied to other embodiments. For example, contents common to parts described in the first embodiment of the second embodiment may be replaced by the description of the first embodiment described above, and such common contents may also be applied to the second embodiment. Furthermore, contents described in the second embodiment that are applicable to the first embodiment may also be applied to the first embodiment. The same applies to other embodiments.

[0049] FIG. 3 is a cross-sectional view of a battery cell according to an embodiment of the present invention, FIG. 4 is a perspective view taken from the upper side of a positive current collector plate included in a battery cell according to an embodiment of the present invention, FIG. 5 is a cross-sectional view taken along A-A' in FIG. 4, FIG. 6 is a perspective view taken from the lower side of a positive current collector plate included in a battery cell according to an embodiment of the present invention, FIG. 7 is an enlarged view of part B in FIG. 4, FIG. 8 is a drawing showing the horn of a welding device in contact with the inner groove of the positive current collector plate in a battery cell according to an embodiment of the present invention, FIG. 9 is a cross-sectional view taken along C-C' in FIG. 8, and FIG. 10 is a cross-sectional view showing the raised portion of the positive current collector plate in contact with the positive terminal in a battery cell according to an embodiment of the present invention.

[0050] Referring to FIG. 3, a battery cell (10) according to one embodiment of the present invention includes an electrode assembly (100), a battery can (200), a positive current collector (300), and a positive terminal (400).

[0051] Referring to FIG. 3, the electrode assembly (100) has a structure in which a positive plate (110), a negative plate (120), and a separator (130) interposed between the positive plate (110) and the negative plate (120) are wound in one direction. Additionally, the electrode assembly (100) can be formed in a jelly roll type.

[0052] For example, the electrode assembly (100) can be manufactured by winding a laminate formed by sequentially stacking a negative plate (120), a separator (130), an anode plate (110), and a separator (130) at least once. Here, the anode plate (110) and the negative plate (120) can be formed in a sheet shape.

[0053] That is, the electrode assembly (100) applied in this embodiment may be a wound-type electrode assembly (100). In this case, an additional separator (130) may be provided on the outer surface of the electrode assembly (100) to insulate it from the battery can (200). That is, the electrode assembly (100) may have a wound structure well known in the relevant technical field without limitation.

[0054] A positive active material is coated on one or both sides of the positive plate (110), and a first uncoated portion (111) on which the positive active material is not coated may be formed at the end of the positive plate (110). The first uncoated portion (111) may be exposed to the outside of the separator (130) while forming a plurality of wound turns based on the center of the electrode assembly (100), and may be used as an electrode tab itself.

[0055] A battery cell (10) according to one embodiment of the present invention may include an embodiment relating to a positive plate (110) in which a first non-existent portion (111) is not formed. However, for convenience of explanation, the following description focuses on the case where a first non-existent portion (111) is formed on the positive plate (110).

[0056] A negative electrode active material is coated on one or both sides of the negative electrode plate (120), and a second uncoated portion (121) on which the negative electrode active material is not coated may be formed at the end of the negative electrode plate (120). The second uncoated portion (121) may be exposed to the outside of the separator (130) while forming a plurality of wound turns with respect to the center of the electrode assembly (100), and may be used as an electrode tab itself.

[0057] A battery cell (10) according to one embodiment of the present invention may include an embodiment relating to a negative plate (120) in which a second non-existent portion (121) is not formed. However, for convenience of explanation, the following description focuses on the case where a second non-existent portion (121) is formed on the positive plate (110).

[0058] That is, at least one of the positive plate (110) and the negative plate (120) may each include an uncoated portion at the long end of the winding direction in which the active material is not coated. In addition, the first uncoated portion (111) and the second uncoated portion (121) may be configured to face in opposite directions.

[0059] Here, the positive active material coated on the positive plate (110) and the negative active material coated on the negative plate (120) can be used without limitation as long as they are active materials known in the art.

[0060] And, the separator (130) can be 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 by laminating them.

[0061] As another example, the separator (130) may be a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high melting point glass fibers, polyethylene terephthalate fibers, etc.

[0062] At least one surface of the separator (130) may include a coating layer of inorganic particles. Additionally, it is possible for the separator (130) itself to be composed of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure combined with a binder such that interstitial volume exists between adjacent particles.

[0063] Additionally, a center hole (140) may be formed in the center of the electrode assembly (100), and the center hole (140) of the electrode assembly (100) may be used for welding the positive terminal (400) and the positive current collector plate (300).

[0064] Referring to FIG. 3, an electrode assembly (100) electrically connected to a positive electrode collector plate (300) is housed in a battery can (200). The battery can (200) may be formed, for example, in a cylindrical shape, so that the electrode assembly (100) is housed inside the battery can (200) and may be electrically connected to the negative electrode plate (120) of the electrode assembly (100). Accordingly, the battery can (200) may have the same polarity as the negative electrode plate (120), that is, a negative electrode. Here, an insulator (500) may be interposed between the battery can (200) and the positive electrode collector plate (300).

[0065] The diameter of the battery can (200) is formed to be larger than the diameter of the electrode assembly (100). A gap of a predetermined size is formed between the battery can (200) and the positive current collector plate (300), and an insulator (500) may be interposed between the gaps.

[0066] If the size of the electrode assembly (100) is increased while the size of the battery can (200) is determined according to the specifications, the total capacity of the battery cell (10) increases, but the gap between the battery can (200) and the electrode assembly (100) decreases.

[0067] That is, to increase the total capacity of the battery cell (10), the size of the electrode assembly (100) is increased, and thus the gap between the battery can (200) and the electrode assembly (100) is reduced. Therefore, to increase the capacity of the battery cell (10), an insulator (500) must be interposed in the reduced gap between the battery can (200) and the electrode assembly (100), and for this purpose, it is desirable that the thickness of the insulator (500) be as thin as possible.

[0068] The battery can (200) may be, for example, a roughly cylindrical receptacle and may be made of a conductive material such as metal. The material of the battery can (200) may be made of a conductive metal, for example, aluminum, steel, stainless steel, etc., but is not limited thereto.

[0069] Referring to FIG. 3, the positive current collector plate (300) is electrically connected to the electrode assembly (100). That is, the positive current collector plate (300) is electrically connected to the positive plate (110) of the electrode assembly (100). The positive current collector plate (300) is made of a conductive metal material and can be connected to the first non-conductive portion (111) of the electrode assembly (100).

[0070] The positive current collector plate (300) can be coupled to the upper portion of the coupling surface formed by bending the end of the first non-reinforced portion (111) in a direction parallel to the positive current collector plate (300). The bending direction of the first non-reinforced portion (111) may be, for example, a direction toward the winding center of the electrode assembly (100).

[0071] When the first non-removable portion (111) has a bent shape like this, the space occupied by the first non-removable portion (111) is reduced, which can lead to an improvement in energy density. In addition, due to the increase in the bonding area between the first non-removable portion (111) and the positive current collector plate (300), it can lead to an improvement in bonding strength and a reduction in resistance.

[0072] Referring to FIG. 4, an inner groove (330) may be formed in the anode current collector plate (300). When an inner groove (330) is formed in the anode current collector plate (300), the occurrence of burrs on the welded area can be reduced. This will be explained in detail below.

[0073] The positive current collector plate (300) can be joined to the electrode assembly (100) in various ways. For example, the positive current collector plate (300) can be joined to the electrode assembly (100) by welding. There are various welding methods, and the positive current collector plate (300) can be joined to the electrode assembly (100) by various welding methods; however, for the convenience of explanation, the following description focuses on the case where the positive current collector plate (300) is joined to the electrode assembly (100) by ultrasonic welding. However, the method of joining the positive current collector plate (300) and the electrode assembly (100) is not limited to this.

[0074] Additionally, the welding device (20) may be an ultrasonic welding machine including a horn (21, see FIG. 8 and 9), and an inner groove (330) may be formed in the part of the anode collector plate (300) where the horn (21) of the welding device (20) contacts. That is, as shown in FIG. 8 and 9, the horn (21) of the welding device (20) may be configured to contact the inner groove (330) of the anode collector plate (300).

[0075] Here, the inner groove (330) can be formed at various locations on the positive current collector plate (300), for example, it can be formed at the center of the positive current collector plate (300), but is not limited thereto.

[0076] The inner groove (330) of the positive current collector plate (300) can be formed in various ways, for example, by press-fitting, but is not limited thereto.

[0077] Referring to FIG. 4 and FIG. 7 together, an intaglio portion (311) in the form of an intaglio may be formed on the first surface (310) of the positive current collector plate (300), and referring to FIG. 6, a relief portion (321) in the form of a relief may be formed on the second surface (320) of the positive current collector plate (300) corresponding to the opposite side of the first surface (310) of the positive current collector plate (300).

[0078] That is, as shown in FIG. 5, an intaglio portion (311) may be formed on the first surface (310) of the positive current collector plate (300), and a relief portion (321) may be formed on the second surface (320) of the positive current collector plate (300) corresponding to the opposite side of the first surface (310). Here, the inner groove (330) of the positive current collector plate (300) may be composed of an intaglio portion (311).

[0079] Referring to FIG. 4 and FIG. 7 together, the engraved part (311) may be configured to include a first part (312), a second part (313), and a third part (314).

[0080] The first part (312) is configured to have a first diameter. In one embodiment, the first part (312) may be formed as a circle having a first diameter (the outer circle of the indentation part (311) or the inner groove (330) in FIG. 7).

[0081] And, the second part (313) has a second diameter smaller than the first diameter of the first part (312) and is formed on the inner side of the first part (312). In one embodiment, the second part (313) may be formed as a circle having a second diameter (the inner circle of the intaglio part (311) or the inner groove (330) in FIG. 7).

[0082] And, the third part (314) may be composed of an inclined part formed at an angle from the first part (312) toward the second part (313).

[0083] That is, the intaglio portion (311) is formed at an angle from the first portion (312) toward the second portion (313), and can be formed so that the diameter decreases as it goes downward along the angle. When the first portion (312) and the second portion (313) are formed in a circular shape, the third portion (314) at all positions can be configured to have the same angle.

[0084] In this way, when the first part (312) and the second part (313) are formed in a circular shape and the third part (314) at all positions is configured to have the same slope, as in FIG. 9, when the horn (21) comes into contact with the third part (314), the horn (21) can be configured to be orthogonal to the first surface (310) of the positive collector plate (300).

[0085] Also, referring again to FIG. 9, the first part (312) may be formed larger than the horn (21) and configured so that the horn (21) enters into the first part (312). At this time, the second part (313) may be formed smaller than the horn (21).

[0086] In such an embodiment, that is, by forming the first part (312) larger than the horn (21) and the second part (313) smaller than the horn (21), the horn (21) can come into contact with the third part (314) while being inserted into the first part (312), and as described above, when the third part (314) has the same inclination at all positions of the first part (312) and the second part (313), the horn (21) can come into contact with the third part (314) so ​​as to be orthogonal to the first surface (310) of the positive current collector plate (300).

[0087] With this configuration, the occurrence of burrs at the welded area can be reduced when the positive current collector plate (300) is joined to the electrode assembly (100) by welding. This is explained with reference to the experimental image below.

[0088] Meanwhile, referring to FIG. 10, the raised portion (321) of the positive collector plate (300) can be joined to the positive terminal (400) by welding. Since the positive portion (321) is formed on the second surface (320) of the positive collector plate (300) to facilitate contact with the positive terminal (400), the joining by welding also has the effect of being easy.

[0089] FIG. 11 is an experimental image showing the degree of burr generation according to the size of the inner groove formed in the positive current collector plate of a battery cell according to one embodiment of the present invention.

[0090] In FIG. 11, the comparative example is a conventional technology in which an inner groove is not formed in the positive current collector plate, whereas in the present invention, an inner groove (330) is formed. Furthermore, experiments were conducted on cases where the height of the inner groove (330) in the present invention was 0.3, 0.4, and 0.5, and all were found to be satisfactory. Here, the height of the inner groove (330) of the present invention is in [mm] units.

[0091] That is, referring to Fig. 11, it can be seen that in the case of the conventional technology in which an inner groove is not formed in the positive collector plate, a large amount of burr is generated.

[0092] However, according to each embodiment of the present invention, in the case of an anode current collector plate (300) having an inner groove (330) formed therein, it can be seen that the occurrence of burrs decreases as the size of the inner groove (330) of the anode current collector plate (300) increases to 0.3 mm or more.

[0093] With this configuration, when the positive current collector plate (300) is joined to the electrode assembly (100) by welding, the occurrence of burrs at the welded area is reduced.

[0094] That is, when an inner groove (330) is formed in the positive collector plate (300), and the positive collector plate (300) is welded by the horn (21) of the welding device (20), the horn (21) penetrates the inner groove (330) of the positive collector plate (300), thereby changing the mechanical structure, and thus the occurrence of burrs on the welded part of the positive collector plate (300) can be reduced.

[0095] In addition, this has the effect of preventing internal short circuits and damage to the battery cell (10) and improving stability.

[0096] The positive terminal (400) is made of a conductive metal material and is electrically connected to the positive current collector plate (300). The positive terminal (400) is electrically connected to the positive plate (110) of the electrode assembly (100) through the positive current collector plate (300), thereby having a positive polarity. Additionally, the battery can (200) is electrically connected to the negative plate (120) of the electrode assembly (100) as described above, thereby having a negative polarity.

[0097] Referring to FIG. 3, a battery cell (10) according to one embodiment of the present invention may include a negative electrode collector plate (600), in which case the negative electrode collector plate (600) is electrically connected to a negative electrode plate (120). The negative electrode collector plate (600) is connected to a second non-conductive portion (121) of an electrode assembly (100). The negative electrode collector plate (600) is made of a conductive metal material such as aluminum, steel, copper, or nickel and may be electrically connected to the second non-conductive portion (121) of the negative electrode plate (120).

[0098] The negative electrode collector plate (600) can be electrically connected to the battery can (200). To this end, at least a portion of the edge portion of the negative electrode collector plate (600) can be fixed by being interposed between the inner surface of the battery can (200) and the sealing gasket (240).

[0099] In one embodiment, at least a portion of the edge portion of the negative electrode collector plate (600) may be fixed to the beading portion (220) by welding while being supported by the beading portion (220) formed at one end of the battery can (200). In a modified embodiment, at least a portion of the edge portion of the negative electrode collector plate (600) may be welded directly to the inner surface of the battery can (200).

[0100] And, at least a portion of the remaining part, excluding the joining portion of the beading portion (220) of the negative electrode collector plate (600), can be joined to the folded surface of the second non-removable portion (121) by welding, for example, laser welding.

[0101] Additionally, at least a portion of the edge of the negative electrode collector plate (600) may be electrically coupled to the surface adjacent to the clamping portion (230) among the upper and lower surfaces of the beading portion (220).

[0102] Referring to FIG. 3, a battery cell (10) according to one embodiment of the present invention may include a cap plate (210), in which case the cap plate (210) may be configured to seal an opening formed in a battery can (200).

[0103] The cap plate (210) may be made of, for example, a metal material to ensure rigidity. Also, the cap plate (210) may be separated from the electrode assembly (100) and provided as non-polar. That is, the cap plate (210) may not have polarity even if it is made of a conductive metal material.

[0104] The fact that the cap plate (210) does not have polarity means that the cap plate (210) is electrically insulated from the battery can (200) and the positive terminal (400). As such, the cap plate (210) does not need to have polarity, and its material does not necessarily have to be a conductive metal.

[0105] And, a vent notch (211) may be formed in the cap plate (210) so as to burst when the pressure inside the battery can (200) exceeds a critical value.

[0106] For example, the vent notch (211) may be formed on both sides of the cap plate (210) and may be formed as at least one of a continuous circular pattern, a discontinuous circular pattern, and a straight pattern on the surface of the cap plate (210). Additionally, the vent notch (211) may be formed as various other patterns.

[0107] A beading portion (220) and a crimping portion (230) may be formed on the battery can (200), and a cap plate (210) may be seated and supported on the beading portion (220) formed on the battery can (200). Additionally, the cap plate (210) is fixed by the crimping portion (230). A sealing gasket (240) may be interposed between the cap plate (210) and the crimping portion (230) of the battery can (200) to ensure airtightness of the battery can (200).

[0108] The beading portion (220) is formed by pressing the outer circumference of the battery can (200) inward. The beading portion (220) supports the electrode assembly (100) so that the electrode assembly (100), which has a size approximately corresponding to the width of the battery can (200), does not come out of the battery can (200), and can also function as a support for the cap plate (210) to be seated. Additionally, the beading portion (220) can support the outer surface of the sealing gasket (240).

[0109] The crimping portion (230) is extended and bent inward toward the battery can (200) to wrap around and secure the edge of the cap plate (210) together with the sealing gasket (240). Additionally, the crimping portion (230) may be formed on the upper or lower part of the beading portion (220).

[0110] Additionally, as a modified embodiment, the present invention includes a case where the battery can (200) does not have at least one of the beading portion (220) and the crimping portion (230). In this case, at least a portion of the edge portion of the negative electrode current collector plate (600) may be configured to be directly welded to the inner surface of the battery can (200) to support the electrode assembly (100).

[0111] FIG. 12 is a schematic diagram showing the configuration of a battery pack including a battery cell according to each embodiment of the present invention.

[0112] Referring to FIG. 12, a battery pack (30) according to one embodiment of the present invention may include one or more battery cells (10) according to each embodiment of the present invention as described above. In addition, the battery pack (30) may further include a pack case (31) for housing the battery cells (10), and various devices for controlling the charging and discharging of the battery cells (10), such as a BMS, a current sensor, a fuse, etc.

[0113] FIG. 13 is a drawing for explaining a vehicle including a battery pack according to each embodiment of the present invention.

[0114] Referring to FIG. 13, a vehicle (40) according to one embodiment of the present invention may include one or more battery cells (10) or battery packs (30) according to each of the above embodiments. Here, the vehicle (40) includes various vehicles configured to use electricity, such as, for example, electric vehicles or hybrid vehicles.

[0115] In this specification, where terms indicating directions such as up, down, left, and right are used, these terms are used merely for convenience of explanation, and it is obvious to those skilled in the art that they may vary depending on the location of the object or the position of the observer.

[0116] Although the present invention has been described above by means of 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 set forth below by those skilled in the art to which the present invention pertains. Therefore, the embodiments disclosed above should be considered in an illustrative rather than a restrictive sense. That is, the scope of the true technical spirit of the present invention is indicated in the claims, and all variations within the equivalent scope thereof should be interpreted as being included in the present invention.

[0117] The present invention relates to a battery cell, a battery pack including the same, an automobile, and a positive current collector, and is particularly applicable to industries related to secondary batteries.

Claims

1. A battery cell comprising an electrode assembly including a positive plate, a negative plate, and a separator, a battery can in which the electrode assembly is housed, a positive current collector plate electrically connected to the electrode assembly, and a positive terminal electrically connected to the positive current collector plate, A battery cell in which an inner groove is formed in the portion of the positive current collector plate where the welding device contacts.

2. In Paragraph 1, An intaglio portion is formed on the first surface of the anode current collector plate, and a relief portion is formed on the second surface of the anode current collector plate corresponding to the opposite side of the first surface. A battery cell characterized in that the inner groove is composed of an engraved portion.

3. In Paragraph 1, A battery cell characterized in that the inner groove is formed in the exact center of the positive current collector plate.

4. In Paragraph 2, The above welding device is an ultrasonic welder including a horn, and the battery cell is characterized in that the horn contacts the inner groove.

5. In Paragraph 4, The above-mentioned engraved part is, A first part having a first diameter; A second part formed on the inner side of the first part having a second diameter smaller than the first diameter of the first part; and A battery cell characterized by including a third part formed inclined from the first part toward the second part.

6. In Paragraph 5, A battery cell characterized in that the first part and the second part are formed in a circular shape, and the third part has the same slope at all positions.

7. In Paragraph 5, A battery cell characterized in that the first part is formed larger than the horn, and the horn is configured to enter the interior of the first part.

8. In Paragraph 9, A battery cell characterized in that the above-mentioned second part is formed to be smaller than the above-mentioned horn.

9. In Paragraph 8, A battery cell characterized by the above horn contacting the above third part.

10. In Paragraph 9, A battery cell characterized in that the above horn contacts the third part so as to be orthogonal to the first surface of the above positive current collector plate.

11. In Paragraph 2, A battery cell characterized in that the above-mentioned raised portion is joined to the above-mentioned positive terminal by welding.

12. A battery pack comprising at least one battery cell according to any one of claims 1 to 11.

13. An automobile comprising at least one battery cell according to any one of paragraphs 1 to 11.

14. A positive current collector that electrically connects an electrode assembly and a positive terminal in a battery cell including a battery can, An anode current collector plate characterized by having an inner groove formed in the portion where the welding device contacts the anode current collector plate.

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