Battery cell, battery pack comprising same, vehicle, and manufacturing method therefor

Abstract

The present invention relates to a battery cell capable of preventing damage due to welding heat, a battery pack comprising same, a vehicle, and a manufacturing method therefor, the battery cell being characterized by comprising: a can having an open end portion on one side; an electrode assembly accommodated in the can; a current collector electrically connected to the electrode assembly; a cap covering the open end portion; and a welding part in which the can and the cap are bonded by welding, wherein the can comprises a beading portion press-fitted inward along the circumference of the vicinity of the open end portion at a side portion of the can, and a crimping portion bent inward along the circumference of the open end portion at the side portion of the can so as to surround and fix the edge of the cap.

Description

Battery cell, battery pack including same, vehicle and manufacturing method thereof

[0001] The present invention relates to a battery cell, a battery pack including the same, an automobile, and a method for manufacturing the same. More specifically, the present invention relates to a battery cell capable of preventing damage caused by welding heat, a battery pack including the same, an automobile, and a method for manufacturing the same. This application claims priority to Korean Patent Application No. 10-2023-0190298, filed on December 22, 2023, the entire contents of which are incorporated herein by reference.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0136987, filed on October 8, 2024, and all contents disclosed in the specification and drawings of the said application are incorporated by reference into this application.

[0003] Secondary batteries, which boast high electrical properties such as high energy density and easy applicability across a wide range of product categories, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) powered by electrical power sources. These batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0004] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, i.e., unit battery cells, is approximately 2.5 V to 4.5 V. Therefore, when a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Furthermore, depending on the charge / discharge capacity required for the battery pack, a number of battery cells are connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge / discharge capacity.

[0005] Meanwhile, the process of manufacturing a battery cell using a cylindrical can includes the steps of deep drawing a metal sheet to form a circular bottom portion and a circular tubular side wall member connected thereto, accommodating an electrode assembly therein, and then covering the open end of the side wall member with a cap to finish. At this time, a current collector plate is provided at one of the axial ends of the electrode assembly facing the open end so as to be in contact with and electrically connected to the electrode tab of the electrode assembly. The current collector plate is connected to the cap or the side wall member by welding or the like so as to be in contact with and electrically connected to the cap or the side wall member.

[0006] That is, in the process of welding the current collector plate to the cap or side wall member, the current collector plate must remain in close contact with the cap or side wall member. However, in general, for this purpose, a jig is required for closely contacting the current collector plate and the cap or the current collector plate and the side wall member, and in addition, a mask is required for exposing the welding area. At this time, in order to closely contact the current collector plate to the cap or side wall member through the mask or jig, a space must be provided inside the can to accommodate the mask or jig. However, this space remains as an empty space after the mask or jig is removed, resulting in a problem in that the internal volume of the can cannot be efficiently utilized.

[0007] Accordingly, a method of welding by forcibly pressing the cap against the current collector or can without a mask or jig has been studied. However, this welding method is also cumbersome because it requires temporary fixing of the parts to be welded prior to the welding process. Furthermore, if component tolerances or assembly errors occur, the welding laser beam can be directly irradiated into the can due to the tolerances at the connection points between the can, current collector, and cap, damaging the electrode assembly.

[0008] In particular, to simultaneously weld the can's sidewall, cap, and current collector, a large amount of heat energy must be generated to melt all contact points between them. This excessive welding heat can be transferred to the separator of the electrode assembly, potentially causing deterioration (melting, pore closure, etc.) or even decomposition of the separator.

[0009] Furthermore, in order to weld the edges of the can and the cap, electrolyte and other substances must not remain at the welded area. Therefore, a process must be added to thoroughly clean the area where the electrolyte will be welded after injection. To avoid the hassle of this cleaning process, a method of sealing the can and cap before injecting the electrolyte could be considered. However, this method also has the drawback of requiring the cumbersome process of sealing the can opening with the cap, then injecting the electrolyte through a separate injection port, and then re-sealing the port.

[0010] Therefore, in the welding process of manufacturing the battery cell, there has been a need for research on a battery cell structure that can prevent damage to the electrode assembly due to welding heat and does not require a separate electrolyte washing process.

[0011] Accordingly, the technical problem to be achieved by the present invention is to provide a battery cell, a battery pack including the same, an automobile, and a method for manufacturing the same, in which welding heat does not affect an electrode assembly.

[0012] In addition, the present invention provides a battery cell, a battery pack including the same, an automobile, and a manufacturing method thereof, which do not cause damage to the electrode assembly even if a dimensional error of the parts or an assembly error of the parts occurs.

[0013] In addition, the present invention provides a battery cell, a battery pack including the same, an automobile, and a manufacturing method thereof, in which a welding process can be smoothly performed without additional processes or installations such as welding or jigs.

[0014] In addition, the present invention provides a battery cell, a battery pack including the same, a vehicle, and a method for manufacturing the same, which do not require a separate process for cleaning the welded part.

[0015] In addition, the present invention provides a battery cell, a battery pack including the same, a vehicle, and a method for manufacturing the same, which can achieve weight reduction by omitting a gasket for sealing or insulation.

[0016] In addition, the present invention provides a battery cell, a battery pack including the same, an automobile, and a method for manufacturing the same, which can sufficiently secure the sealing performance of the can.

[0017] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0018] In order to solve the above object, the present invention provides a battery cell comprising a can having an open end on one side, an electrode assembly accommodated inside the can, a current collector electrically connected to the electrode assembly, a cap covering the open end, and a welding portion in which the can and the cap are joined by welding, wherein the can is characterized in that it has a beading portion pressed inward along a circumference near the open end on a side of the can and a crimping portion bent inward along a circumference of the open end on a side of the can to wrap and fix an edge of the cap.

[0019] In addition, preferably, the beading portion may include a lower inclined recessed portion formed to face downwards as it goes inward, and an upper inclined recessed portion connected to the lower inclined recessed portion and formed to face upwards as it goes inward.

[0020] In addition, preferably, the beading portion may have a slanted shape as a whole, with the lower slanted depression portion and the upper slanted depression portion forming a certain angle.

[0021] Additionally, preferably, the collector plate may include a can connecting portion interposed between the edge of the cap and the crimping portion.

[0022] Additionally, preferably, the can connection portion may be ring-shaped.

[0023] Additionally, preferably, the can connection portion may have a closed loop shape.

[0024] Additionally, preferably, the collector plate may include an outwardly extending portion formed to face upwards as it goes outward.

[0025] Additionally, preferably, the outwardly extending portion may be configured to be in contact with the beading portion.

[0026] Additionally, preferably, the collector plate may include a direction-changing portion bent inwardly.

[0027] Additionally, preferably, the direction changing portion may be interposed between the upper surface of the cap and the lower surface of the bent area of ​​the crimping portion.

[0028] Additionally, preferably, the direction-changing portion may extend inwardly in at least a portion of the area more than the folded area of ​​the crimping portion.

[0029] Additionally, preferably, the welded portion may be seam welded in the folded area or outermost area of ​​the crimped portion.

[0030] Additionally, preferably, the welded portion can be welded together with at least a portion of the current collector plate.

[0031] Additionally, preferably, the welded portion may include at least one of a first welded portion welded along an end portion of the bent region of the crimped portion, and a second welded portion welded along a vicinity of an end portion of the bent region of the crimped portion.

[0032] In addition, preferably, the welded portion is provided in multiple pieces, and at least one of the welded portions may have a closed curve weld shape.

[0033] In addition, preferably, the welded portion is provided in multiple pieces, each of which may have a different penetration depth.

[0034] In addition, preferably, the welding position or penetration depth of the welding part can be varied depending on the shape of the current collector plate.

[0035] In addition, the present invention provides a battery pack including at least one of the above-described battery cells.

[0036] In addition, the present invention provides a vehicle including at least one of the above-described battery packs.

[0037] In addition, the present invention may include a method for manufacturing a battery cell, which comprises the steps of accommodating an electrode assembly in a can, performing beading processing on a side of the can, inserting a cap into an open end of the can, performing crimping processing to seal the open end of the can, and performing double sealing by welding an area where the upper portion of the cap and the can overlap.

[0038] In addition, preferably, the method for manufacturing the battery cell may include a step of injecting an electrolyte into the interior of the can before or after the step of performing the beading process.

[0039] Also, preferably, the double sealing step may be performed such that the collector plate, the cap and the can are welded together.

[0040] Additionally, preferably, the double sealing step may be seam welded so that the penetration depths in the plurality of welding areas are the same or different.

[0041] The battery cell, battery pack including the same, vehicle and manufacturing method thereof according to various embodiments of the present invention have the effect of preventing the adverse effects of welding heat on the battery cell.

[0042] In addition, the battery cell according to various embodiments, the battery pack including the same, the vehicle and the manufacturing method thereof have the effect of simultaneously achieving electrical connection between the can and the collector plate and sealing of the cap.

[0043] In addition, the battery cell according to various embodiments, the battery pack including the same, the vehicle and the manufacturing method thereof have the effect of ensuring weldability, stability and durability.

[0044] In addition, the battery cell according to various embodiments, the battery pack including the same, the vehicle and the manufacturing method thereof have the effect of reducing the welding work of the battery cell.

[0045] In addition, the battery cell according to various embodiments, the battery pack including the same, the vehicle and the manufacturing method thereof have the effect of increasing the energy density of the battery cell by maximizing the volume of the electrode assembly accommodated inside the can.

[0046] In addition, the battery cell according to various embodiments, the battery pack including the same, the vehicle and the manufacturing method thereof have the effect of not requiring a separate cleaning process for the welding process.

[0047] However, the effects that can be obtained through the present invention are not limited to the effects described above, and other technical effects that are not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0048] FIG. 1 is a schematic drawing of a can of a battery cell according to one embodiment of the present invention.

[0049] FIG. 2 is a schematic drawing of an electrode assembly of a battery cell according to one embodiment of the present invention.

[0050] Fig. 3 is a drawing for explaining the configuration of the electrode assembly according to Fig. 2.

[0051] Fig. 4 is a drawing for explaining the state in which the configuration of the electrode assembly according to Fig. 3 is laminated.

[0052] Fig. 5 is a schematic drawing showing a state in which a current collector plate is joined to one end of the electrode assembly according to Fig. 4.

[0053] Fig. 6 is a schematic drawing showing a state in which a current collector plate is joined to the other end of the electrode assembly according to Fig. 4.

[0054] FIG. 7 is a schematic drawing of a current collector plate of a battery cell according to one embodiment of the present invention.

[0055] FIG. 8 is a schematic drawing of a current collector plate of a battery cell according to another embodiment of the present invention.

[0056] FIG. 9 is a drawing for explaining a process of accommodating an electrode assembly of a battery cell according to one embodiment of the present invention inside a can.

[0057] FIG. 10 is a drawing for explaining a process of forming a beading portion in a can of a battery cell and joining a current collector plate and an electrode terminal according to one embodiment of the present invention.

[0058] FIG. 11 is a drawing for explaining a process of covering an open end of a can of a battery cell with a cap according to one embodiment of the present invention.

[0059] FIG. 12 is a drawing for explaining a process of forming a crimping portion in a can of a battery cell according to one embodiment of the present invention.

[0060] Fig. 13 is a drawing for explaining an exemplary relationship between the beading portion and the collector plate of the area FF according to Fig. 12.

[0061] Fig. 14 is a drawing for explaining another exemplary relationship between the beading portion and the collector plate of the area FF according to Fig. 12.

[0062] FIG. 15 is a schematic drawing of a top view of a current collector plate of a battery cell according to one embodiment of the present invention.

[0063] FIG. 16 is a schematic drawing of a top view of a current collector plate of a battery cell according to another embodiment of the present invention.

[0064] FIG. 17 is a schematic drawing of a top view of a current collector plate of a battery cell according to another embodiment of the present invention.

[0065] Fig. 18 is a drawing for explaining an exemplary arrangement of the clamping portion and the collector plate of the can of area F according to Fig. 12.

[0066] Fig. 19 is a drawing for explaining another exemplary arrangement of the clamping portion and the collector plate of the can of area F according to Fig. 12.

[0067] Fig. 20 is a drawing showing the location of a welded portion of a battery cell according to one embodiment of the present invention.

[0068] FIG. 21 is a drawing showing the penetration depth of a weld of a battery cell according to one embodiment of the present invention.

[0069] Fig. 22 is a drawing showing the welding form of a welded portion of a battery cell according to one embodiment of the present invention.

[0070] Fig. 23 is a drawing showing the welding form of a welded portion of a battery cell according to another embodiment of the present invention.

[0071] Figure 24 is a flowchart of a manufacturing process of a battery cell according to one embodiment of the present invention.

[0072] FIG. 25 is a schematic drawing of a battery pack having a battery cell according to one embodiment of the present invention.

[0073] FIG. 26 is a schematic drawing of a vehicle equipped with a battery pack according to one embodiment of the present invention.

[0074] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0075] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0076] Furthermore, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar components will be omitted, and the differences will be described.

[0077] Additionally, to facilitate understanding of the invention, the attached drawings are not drawn to scale and some components may have exaggerated dimensions. Furthermore, identical components may be assigned the same reference numbers in different embodiments.

[0078] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0079] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0080] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0081] Throughout the specification, when reference is made to “A and / or B,” this may mean A, B, or A and B, unless otherwise specifically stated.

[0082] Meanwhile, in this specification, terms indicating directions such as up, down, left, right, front, and back may be used, but these terms are only for convenience of explanation, and it is obvious to a person skilled in the art to which the present invention pertains that these terms may vary depending on the position, arrangement, rotation, and position of the object being targeted, or the position of the observer.

[0083]

[0084] Hereinafter, a battery cell (1) according to various embodiments of the present invention will be described in detail.

[0085] First, the battery cell (1) may be a cylindrical battery cell. Preferably, the battery cell (1) may be a cylindrical battery cell having a form factor ratio (defined as the ratio of the diameter (Φ) to the height (H) of the cylindrical battery cell divided by the height) of approximately 0.4 or greater.

[0086] Here, the form factor may refer to a value indicating the diameter and height of a cylindrical battery cell. The cylindrical battery cell may be a 46110 cell, a 48750 cell, a 48110 cell, a 48800 cell, or a 46800 cell by applying a numerical value indicating the form factor. Here, the first two numbers indicate the diameter of the cell, the next two numbers indicate the height of the cell, and the last number 0 indicates that the cross-section of the cell is circular.

[0087] In addition, the above battery cell (1) can be applied to cylindrical battery cells having a form factor ratio of approximately 0.4 or less, such as 18650 cells, 21700 cells, etc., and the type is not limited to cylindrical battery cells.

[0088]

[0089] Fig. 1 is a schematic drawing of a can (10) of a battery cell (1) according to one embodiment of the present invention. The battery cell (1) according to one embodiment of the present invention may include a can (10) with one side open.

[0090] Referring to Fig. 1, the can (10) may be composed of a side wall member (11) and a bottom member (12).

[0091] The can (10) may have a cylindrical structure for the cylindrical battery cell. In this case, the side wall member (11) may form a cylindrical side surface of the can (10), and the bottom member (12) may form one end of the cylinder. That is, the bottom member (12) may be a closed end of the can (10), and the other end of the can (10) facing the bottom member (12) may be open, thereby becoming an open end.

[0092] The above-mentioned floor member (12) may be in the shape of a disk with a through hole formed in the center, and may be a member formed by deep drawing a metal sheet with nickel plated on the surface of steel.

[0093] The above side wall member (11) may be in the shape of a tube surrounding the bottom member (12), and may be a member formed by deep drawing a metal sheet with nickel plated on the surface of steel. Of course, the materials of the bottom member (12) and the side wall member (11) are not limited thereto.

[0094] A first electrode terminal (13) can be fitted into the through hole of the bottom member (12). The first electrode terminal (13) can be fixed to the bottom member (12) by being riveted while a gasket (14) is interposed therebetween. The gasket (14) is interposed between the first electrode terminal (13) and the bottom member (12), sealing the interior of the can (10) to prevent leakage of the electrolyte, and electrically insulating the first electrode terminal (13) and the bottom member (12).

[0095] However, the method of connecting the first electrode terminal (13) and the bottom member (12) is not limited to this. For example, if there is a structure that can seal between the first electrode terminal (13) and the bottom member (12) and electrically insulate the first electrode terminal (13) and the bottom member (12), various other fixing methods, such as a bolt-nut joint method, a glass seal method, or a chrome coating & PP-MAH thermal bonding method, can also be applied.

[0096] Accordingly, the first electrode terminal (13) can have a first polarity, and the can (10) can have a second polarity. That is, both the bottom member (12) and the side wall member (11) connected thereto can have a second polarity. Accordingly, the bottom member (12) can have both the first electrode terminal (13) having a first polarity and the second electrode terminal (15) having a second polarity arranged thereon. The first electrode terminal (13) can be a positive terminal, and the second electrode terminal (15) can be a negative terminal. Of course, the opposite may also be the case.

[0097]

[0098] FIG. 2 is a schematic drawing of an electrode assembly (20) of a battery cell (1) according to one embodiment of the present invention, FIG. 3 is a drawing for explaining the configuration of the electrode assembly (20) according to FIG. 2, and FIG. 4 is a drawing for explaining the configuration of the electrode assembly (20) according to FIG. 3 in a laminated state.

[0099] A battery cell (1) according to one embodiment of the present invention may include the electrode assembly (20) accommodated inside the can (10).

[0100] Referring to FIGS. 2 to 4, the electrode assembly (20) can be manufactured in a jelly-roll shape in which the electrodes (21, 22) and the separator (28) are wound around a core axis.

[0101] The first electrode (21), the second electrode (22), and the separator (28) may each have a predetermined width and be formed to extend in the longitudinal direction. The first electrode (21) may be an anode, and the second electrode (22) may be a cathode. Of course, the opposite may also be the case.

[0102] The first electrode (21) and the second electrode (22) may be manufactured in the form of sheets. The electrode sheet may be configured in a form in which an active material layer (24) is applied to at least a portion of the surface of a metal foil (23). The electrode sheet may have a holding portion (25) region on which the active material layer (24) is applied, and a non-coated portion (26) region on which the active material layer (24) is not applied. The positive electrode sheet may have the non-coated portion (26) region on one side in the width direction, and the negative electrode sheet may have the non-coated portion (26) region on the other side in the width direction.

[0103] The above-mentioned non-conductive part (26) can itself function as an electrode tab.

[0104] The above-mentioned non-conductive portion (26) can form a plurality of notched tabs (27) in the shape of flags by forming notches at a predetermined interval. The plurality of notched tabs (27) can be in the shape of an equilateral trapezoid arranged along the longitudinal direction. However, the present invention is not limited thereto, and can be in various shapes such as a semicircle, a semi-ellipse, a triangle, a rectangle, a parallelogram, etc.

[0105] In addition, the plurality of notching tabs (27) may have the same width. However, the width of the plurality of notching tabs (27) may be gradually or stepwise widened from the core side to the outer circumference side.

[0106] In addition, the plurality of notching tabs (27) may be formed in a form in which the height of the notching tabs (27) gradually increases from the core side to the outer circumference side. However, the height of the plurality of notching tabs (27) may be implemented in a form in which it is constant or gradually decreases.

[0107] In addition, the plurality of notching tabs (27) may have a structure in which the notching tabs (27) are deleted in a predetermined section of the centripetal end of the non-coated portion (26) and a predetermined section of the centrifugal end. However, it goes without saying that the notching tabs (27) may not be deleted in the centripetal end of the non-coated portion (26), and the notching tabs (27) may not be deleted in the centrifugal end of the non-coated portion (26).

[0108] In addition, the plurality of notching tabs (27) may be bent radially in the electrode assembly (20) and flattened. In addition, the notching tabs (27) may be bent radially inward or outward in the electrode assembly (20).

[0109] In addition, the plurality of notching tabs (27) may be bent one by one during the process of forming the electrode assembly (20) in the form of a jelly-roll. Alternatively, the notching tabs (27) may be bent all at once after forming the electrode assembly (20) in the form of a jelly-roll.

[0110] In this way, the notched tabs (27) of the first electrode (21) and the notched tabs (27) of the second electrode (22), which are bent and overlapped in the radial direction, can provide a plane substantially perpendicular to the axial direction at each of the axial ends of the electrode assembly (20).

[0111]

[0112] FIG. 5 is a drawing schematically showing a state in which a current collector plate (31) is joined to one end of the electrode assembly (20) according to FIG. 4, FIG. 6 is a drawing schematically showing a state in which a current collector plate (32) is joined to the other end of the electrode assembly (20) according to FIG. 4, FIG. 7 is a drawing schematically showing the current collector plate (32) of a battery cell (1) according to one embodiment of the present invention, FIG. 8 is a drawing schematically showing the current collector plate (32) of a battery cell (1) according to another embodiment of the present invention, and FIG. 9 is a drawing for explaining a process of accommodating the electrode assembly (20) of the battery cell (1) according to one embodiment of the present invention inside the can (10).

[0113] The battery cell (1) according to one embodiment of the present invention may include a current collector plate (31, 32) electrically connected to the electrode assembly (20).

[0114] Referring to FIGS. 5 and 6, the current collector (30) can be electrically connected to at least one axial end of the electrode assembly (20).

[0115] The above current collector plate (30) may include a first current collector plate (31) electrically connected to the first electrode (21) and a second current collector plate (32) electrically connected to the second electrode (22).

[0116] The first collector plate (31) and the second collector plate (32) can be joined to substantially flat surfaces provided by bending the notched tabs (27) exposed at both axial ends of the electrode assembly (20). The first collector plate (31) may be a positive collector plate made of aluminum, and the second collector plate (32) may be a negative collector plate made of copper. However, the material of the collector plates (31, 32) need not be limited thereto. In addition, the collector plates (31, 32) may be manufactured by punching, trimming, piercing, and bending a metal sheet, and the manufacturing method is not limited thereto.

[0117] Here, the first collector plate (31) and the second collector plate (32) may be formed with different or identical structures. In FIGS. 5 and 6, the first collector plate (31) and the second collector plate (32) are exemplified as having different structures, but are not limited thereto. In addition, the present invention is not limited to the exemplary forms of each configuration illustrated in the drawings, and may be formed in various other forms.

[0118] The above first collector plate (31) may include a terminal connection portion (311) and an electrode connection portion (313).

[0119] The terminal connection portion (311) may be configured to extend radially from the center of the first current collector plate (31) and cover at least a portion of the core hollow portion of the electrode assembly (20). The first current collector plate (31) may further include a ring portion (312) configured to connect the centrifugal edge of the terminal connection portion (311) in a circumferential direction.

[0120] The electrode connection portion (313) may extend from the ring portion (312) toward the center, but may not be connected to the terminal connection portion (311). At this time, the electrode connection portion (313) may be joined to the notched tab (27) of the first electrode (21) of the electrode assembly (20) by laser welding or the like before the electrode assembly (20) is placed in the can (10). The welding line of the laser may extend radially.

[0121] The above second collector plate (32) may include an inner ring (321), a hole (322), an electrode connection part (323), and a can connection part (324).

[0122] The inner ring (321) may be configured to surround the core hollow portion of the electrode assembly (20), and the hole (322) may be configured to be opened in a shape corresponding to the core hollow portion of the electrode assembly (20).

[0123] The electrode connection portion (323) may be configured to extend radially from the inner ring portion (321). At this time, the electrode connection portion (323) may be joined to the notched tab (27) of the second electrode (22) of the electrode assembly (20) by laser welding or the like before the electrode assembly (20) is placed in the can (10). The welding line of the laser may extend radially.

[0124] The can connection portion (324) may be configured at least in a portion of the edge or near the edge of the second current collector plate (32) so as to be connected to the second current collector plate (32) inside the can (10).

[0125] Referring to FIGS. 7 and 8, the can connection portion (324) may include an outward extension portion (325) and a direction change portion (326).

[0126] The above-mentioned outward extension portion (325) can be formed to extend radially outward from the electrode connection portion (323) and the inner ring portion (321).

[0127] The above-mentioned outward extension portion (325) may be provided with a form inclined at a certain angle so as to extend axially outward as it extends radially outward. This structure may facilitate connection or joining of the second collector plate (32) and the can (10) within the can (10).

[0128] The above-mentioned direction changing portion (326) can be formed to extend a certain length from the radially outer end of the above-mentioned outward extension portion (325).

[0129] The above-described direction changing portion (326) may be formed at an angle that is the same as or different from the angle at which the outward extension portion (325) is extended. For example, the above-described direction changing portion (326) may be formed in a form that is extended axially outward or axially long. In this case, when forming the crimping portion (120) to be described later, it may be bent together with the crimping portion (120) of the can (10) and may be extended so as to be bent radially inward. This structure can facilitate the assembly of the can (10) and the cap (40) to be described later at one time, and can further reduce assembly errors.

[0130] In addition, the direction change portion (326) may be formed in a bent shape before the crimping process described below, and configured to extend radially inward. This structure can be bent radially inwardly of the second current collector plate (32) to perform the crimping process at a preset angle.

[0131] Referring to FIG. 9, the first collector plate (31) and the second collector plate (32) can be joined to the electrode assembly (20) before the electrode assembly (20) is placed in the can (10), as described above. Of course, it is also possible to insert the second collector plate (32) into the can (10) and then join it to the electrode assembly (20) after the electrode assembly (20) with only the first collector plate (31) joined is placed in the can (10).

[0132] The above electrode assembly (20) can be accommodated inside the can (10) in a state where the first current collector (31) is aligned toward the bottom member (12) of the can (10).

[0133] At this time, an insulator (16) may be interposed between the first collector plate (31) and the bottom member (12) of the can (10). This structure may electrically insulate the first collector plate (31) and the bottom member (12). At this time, at least a portion of the can connection portion (324) of the second collector plate (32) may be in contact with the inner peripheral surface of the side wall member (11). In addition, the second collector plate (32) may be arranged to face the open end of the side wall member (11).

[0134]

[0135] FIG. 10 is a drawing for explaining a process of forming a beading portion (110) in the can (10) of the battery cell (1) according to one embodiment of the present invention and joining the current collector (30) and the electrode terminal (13, 15), FIG. 11 is a drawing for explaining a process of covering an open end of the can (10) of the battery cell (1) according to one embodiment of the present invention with a cap (40), and FIG. 12 is a drawing for explaining a process of forming a crimping portion (120) in the can (10) of the battery cell (1) according to one embodiment of the present invention.

[0136] Referring to FIGS. 10 to 12, a battery cell (1) according to one embodiment of the present invention may include a beading portion (110) of the can (10), a cap (40), and a crimping portion (120) of the can (10) as a configuration for sealing the inside of the can (10).

[0137] The beading portion (110) of the can (10) may be formed in a form in which a certain portion is pressed inward along the circumference near the open end of the can (10) from the side of the can (10). As a result, when the electrode assembly (20) is accommodated in the can (10), the position of the electrode assembly (20) can be regulated to a certain extent, and the process of sealing the interior of the can (10) can be facilitated in the future.

[0138] At this time, the terminal connection portion (311) of the first collector plate (31) can be joined to the first electrode terminal (13) coupled to the can (10) by resistance welding, ultrasonic welding, laser welding, or the like. The welding device (A) for welding the first collector plate (31) and the first electrode terminal (13) can approach the back surface of the center of the terminal connection portion (311) of the first collector plate (31) through the core hollow portion of the electrode assembly (20) from the open end of the can (10) to perform welding. Of course, in addition to this, the first collector plate (31) and the first electrode terminal (13) can also be joined by brazing or soldering. That is, various methods can be applied to the joining of the first collector plate (31) and the first electrode terminal (13) as long as they are joining methods that can electrically connect them and fix them to each other.

[0139] Accordingly, in the battery cell (1) according to one embodiment of the present invention, after forming a beading portion (110) in the can (10) and connecting the first current collector (31) and the first electrode terminal (13), an electrolyte can be injected into the inside of the can (10). Accordingly, after the inside of the can (10) is sealed, the electrolyte can be injected again through a separate injection port, and the process of closing the injection port again or the cleaning process for welding can be omitted, thereby simplifying the entire process.

[0140] The above cap (40) may be configured to cover the open end of the can (10).

[0141] That is, the cap (40) may be configured as a cover structure that effectively seals the open end of the can (10) to protect the internal electrolyte and electrode portion of the battery cell (1) from the external environment and maintain long-term performance of the battery cell (1).

[0142] The above cap (40) may be made mainly of a metallic material for electrical connection with the second collector plate (32).

[0143] The cap (40) may be fixed to the open end of the can (10) or may be disc-shaped so as to seal the open end of the can, but is not limited thereto. In addition, the thickness of the cap (40) provides sufficient strength to prevent deformation in a high temperature or high pressure environment, and can secure durability to prevent leakage of the internal electrolyte. At this time, the edge of the cap (40) may be configured to be positioned near the edge of the second collector plate (32) or on the outwardly extending portion (325) of the second collector plate (32).

[0144] The crimping portion (120) of the can (10) may be configured to be bent inward along the circumference of the open end of the can (10) from the side of the can (10). At this time, the crimping portion (120) of the can (10) may wrap around and fix the edge of the cap (40).

[0145] Accordingly, the battery cell (1) according to one embodiment of the present invention can be pressed and tightly connected through crimping processing even if there is a dimensional error in each component of the battery cell (1) or an assembly error between components.

[0146]

[0147] FIG. 13 and FIG. 14 are drawings for explaining an exemplary relationship between the beading portion (110) of the can (10) in area F according to FIG. 12 and the current collector (30).

[0148] Referring to FIGS. 13 and 14, the beading portion (110) of the can (10) may be processed to be radially inwardly recessed from the side of the can (10) and configured so that a flat surface perpendicular to the axial direction is not formed.

[0149] The beading portion (110) of the can (10) can maintain a form inclined at a certain angle. That is, the beading portion (110) of the can (10) does not need to provide a strong pressing surface by itself to seal the cap (40) to the can (10). When forming the crimping portion (120) of the can (10), it is sufficient to support the pressing force of the cap (40) pressed axially inward by the crimping portion (120) of the can (10). For example, the beading portion (110) can be formed with a pressing depth (h2) that can maintain a form inclined at a certain angle, rather than the pressing depth (h1) that was required in the past, thereby reducing the pressure applied to the can (10).

[0150] Accordingly, the beading portion (110) of the can (10) may include a lower inclined recessed portion (111) formed to face downwards as it goes inward, and an upper inclined recessed portion (112) formed to face upwards as it goes inward and connected to the lower inclined recessed portion (111).

[0151] The lower inclined recessed portion (111) and the upper inclined recessed portion (112) may be configured to form an inclined surface that is inclined as a whole by forming a certain angle so that the beading portion (110) of the can (10) does not form a flat surface perpendicular to the axial direction.

[0152] Accordingly, the battery cell (1) according to one embodiment of the present invention can have a shallow forming or pressing depth of the beading portion (110) of the can (10), so that the durability of the beading portion (110) of the can (10) may not become weak.

[0153] The beading portion (110) of the can (10) may be formed, as described above, in a state where the second collector plate (32) is joined to the electrode assembly (20). At this time, the second collector plate (32) may be configured to be pressed between the outwardly extending portion (325) and the electrode assembly (20).

[0154] In the beading process, the beading portion (110) of the can (10) may be configured to be in contact with the lower surface of the outwardly extending portion (325) of the second collector plate (32). That is, the outwardly extending portion (325) of the second collector plate (32) may be in contact with the beading portion (110) of the can (10). As a result, the second collector plate (32) and the beading portion (110) of the can (10) are brought into closer contact, thereby more effectively supporting the pressure in the crimping process.

[0155] In addition, the beading portion (110) of the can (10) may be pressed into a predetermined depth so as to support a certain portion of the lower portion of the outwardly extended portion (325) of the second collector plate (32) without being in complete contact with the outwardly extended portion (325) of the second collector plate (32). For example, the beading portion (110) may be formed with a press-in depth (h3) that can maintain a shape inclined at a certain angle without being in complete contact with the outwardly extended portion (325) of the second collector plate (32) at a conventionally required press-in depth (h1), thereby further reducing the pressure applied to the can (10). Accordingly, the crimping portion (120) of the can (10) wraps around the edge of the cap (40) to sufficiently support it, so that excessive forming of the beading portion (110) of the can (10) may not be required.

[0156] Accordingly, the battery cell (1) according to the present embodiment has the effect of protecting the durability of the beading portion (110) of the can (10), thereby extending the life of the battery cell (1).

[0157]

[0158] Figures 15 to 17 are schematic drawings showing exemplary top views of the current collector plate (30) of the battery cell (1) according to one embodiment of the present invention.

[0159] The above-described current collector (30) may include the can connection portion (324) that can be electrically connected to the can (10), as described above.

[0160] Referring to FIGS. 15 to 17, the can connection portion (324) may be interposed between the edge of the cap (40) and the crimping portion (120) of the can (10), and may employ various structures that can be electrically connected to the can (10).

[0161] For example, the can connection portion (324) may be a ring shape or a closed loop shape. The closed loop shape may be configured as a closed ring shape formed on the outer periphery of the crimping portion (120) of the can (10). In particular, by providing strength and durability, it is possible to maintain structural integrity for sealing and prevent unnecessary damage.

[0162] The can connection portion (324) may be made of a metallic material and may be electrically connected to the can (10) and the cap (40). In addition, the can connection portion (324) may be formed to an appropriate size corresponding to the outer circumference of the open end of the can (10). This ensures integrity during the manufacturing process of the battery cell (1) and maintains a stable seal without deformation even during long-term storage.

[0163] Accordingly, in the battery cell (1) according to one embodiment of the present invention, the can connection portion (324) is interposed in close contact between the edge of the cap (40) and the crimping portion (120) of the can (10) that secures the edge of the cap (40), so that an additional gasket for sealing may not be provided. Accordingly, the internal volume of the can (10) can be secured, thereby maximizing the space utilization and energy density of the battery cell (1).

[0164] In addition, the can connection part (324) may be configured to be interposed in a portion of an area between the edge of the cap (40) and the crimping part (120) of the can (10). That is, the can connection part (324) may be configured to contact the inner surface of the crimping part (120) of the can (10) and the edge of the cap (40) at a predetermined interval. The can connection part (324) may include the direction changing part (326), so that it can sufficiently perform fixing for electrical connection and sealing between the can (10) and the cap (40). Accordingly, since a gasket for sealing may not be additionally provided, the space utilization and energy density of the battery cell (1) can be maximized.

[0165] Accordingly, the battery cell (1) according to one embodiment of the present invention can simultaneously secure the can (10) and the cap (40) for electrical connection and sealing, without additionally providing a gasket for sealing or insulation, by having the can connection portion (324) of the current collector (30) function as a gasket. As a result, the gasket bonding process for sealing or insulation or the inter-component tack welding process can be omitted. Accordingly, the welding man-hours of the welding portion (50) described later can be reduced, thereby increasing the production efficiency of the battery cell (1) and reducing the production cost.

[0166]

[0167] FIG. 18 and FIG. 19 are drawings for explaining an exemplary arrangement of the crimping portion (120) of the can (10) and the current collector (30) of area F according to FIG. 12.

[0168] Referring to FIGS. 18 and 19, the direction changing portion (326) of the current collector plate (30) is bent inward, and at least a portion of the area can be interposed between the upper surface of the cap (40) and the lower surface of the bent area of ​​the crimping portion (120) of the can (10). Accordingly, even if a dimensional error of the component or an assembly error between the components occurs during the manufacturing process of the battery cell (1), the current collector plate (30) can be further pressed upwardly and downwardly against the edge of the cap (40) by the crimping portion (120) of the can (10). Accordingly, when sealing the open end of the can (10) by welding, which will be described later, the fact that the area where each component is in close contact with each other is large can be sufficiently utilized in the crimping sealing method.

[0169] The direction changing portion (326) may extend further inwardly than the folded region of the crimping portion (120) of the can (10) at least in a portion thereof. For example, the direction changing portion (326) may be configured to extend radially inwardly by a certain portion thereof than the folded region of the crimping portion (120) of the can (10) and be exposed to the outside. In addition, the direction changing portion (326) may be configured to expose a portion of the outer circumferential surface of the end of the crimping portion (120) of the can (10) at a certain interval to the outside.

[0170] Accordingly, the battery cell (1) according to one embodiment of the present invention can provide an area in which the current collector plate (30) can also be welded at once when the can (10) and the cap (40) are welded to seal the open end of the can (10). That is, the electrical connection and sealing process between components of the battery cell (1) can be performed at once with just one welding, thereby achieving economic advantages due to process simplification and component reduction.

[0171]

[0172] As described above and illustrated in FIGS. 1 to 19, the battery cell (1) according to one embodiment of the present invention includes the can (10), the electrode assembly (20), the current collector (30), and the cap (40), and the can (10) may include the beading portion (110) and the crimping portion (120). In this way, the battery cell (1) can overcome dimensional errors of components or assembly errors between components during the manufacturing process of the battery cell (1) by introducing a crimping process into the manufacturing process.

[0173] However, conventionally, when closing the open end of the can (10), a process of electrically connecting the current collector (30) to the cap (40) or the can (10) and a process of connecting the cap (40) to the can (10) were performed separately. This increase in labor became a factor that lowered the production efficiency of the battery cell (1) and increased the production cost. In addition, when welding is performed at once using a welding sealing method, the welding heat generated during welding may be transmitted to the inside of the can (10), or a welding laser may be introduced into the inside of the can (10) through a gap created by an assembly error of the battery cell (1). This may affect the electrode assembly (20) and cause damage to the separator.

[0174] Accordingly, in order to solve the above-described problem, the sealing method of the battery cell (1) according to one embodiment of the present invention may be implemented by using a welding method, but incorporating the crimping sealing method of the battery cell (1) as described above.

[0175]

[0176] Fig. 20 is a drawing showing the position of a welded portion (50) of a battery cell (1) according to one embodiment of the present invention.

[0177] Referring to FIG. 20, in addition to the above-described configuration, the battery cell (1) according to one embodiment of the present invention may further include a welding portion (50).

[0178] The above welding portion (50) may be configured so that the can (10) and the cap (40) are welded together. Thus, the can (10) and the cap (40) may be configured to be mutually conductive through the welding portion (50).

[0179] The sealing method of the above welding part (50) can be achieved by using a laser.

[0180] The above welding portion (50) can be welded in a compressed state of each component by processing the crimping portion (120) of the can (10). Accordingly, since each component is already in close contact with each other before forming the welding portion (50), a separate tack welding process between each component may not be required. Accordingly, a tack welding process for joining the cap (40) to the side wall member (11) inside the can (10), etc., can be omitted, and the entire process can be simplified. The welding portion (50) can be welded in this way in an area or part where the can (10), the current collector (30), and the cap (40) are overlapped and compressed with each other.

[0181] Accordingly, the battery cell (1) according to the present embodiment can reduce the influence on the electrode assembly (20) by increasing the heat transfer path of the welding heat from the welding portion (50) to the electrode assembly (20), and can prevent damage to the electrode assembly (20) by preventing melting or deformation of the separator (28).

[0182] In addition, the battery cell (1) according to the present embodiment has a beading portion (110) and a crimping portion (120) formed on the can (10), so that the edge of the cap (40) is pressed and adhered, thereby increasing the contact area between the components. Accordingly, a gap or lifting between the edge of the cap (40) and the can (10), which is caused by an assembly or processing error during the manufacturing process of the battery cell (1), can be eliminated or prevented, thereby preventing the welding laser (L) from penetrating the electrode assembly (20). Accordingly, the welding laser (L) does not penetrate the interior of the can (10), ultimately extending the life of the battery cell (1).

[0183] In addition, the battery cell (1) according to the present embodiment can implement electrical connections and a sealing structure between components of the battery cell (1) together by welding, and as described above, the can connection portion (324) of the current collector (32) can function as a gasket, so that a gasket for sealing or insulation can be omitted. Accordingly, the volume of the electrode assembly (20) accommodated inside the can (10) can be secured to the maximum extent possible, thereby increasing the energy density of the battery cell (1).

[0184] The above welding portion (50) can be welded in the folded area or the outermost area of ​​the crimping portion (120) of the can (10). That is, after the crimping portion (120) is formed in the can (10), welding of the battery cell (1) can be performed in the folded area or the outermost area of ​​the crimping portion (120) of the can (10). For example, welding can be performed in the upper surface (L1, L2), which is the folded area of ​​the crimping portion (120) of the can (10), and welding can be performed in the side surface (L3, L4), which is the outermost area. Preferably, it is performed as a seam welding, so as to continuously form a welding line, provide a strong joint at the welding site, and maintain the airtightness of the seal.

[0185] Accordingly, the battery cell (1) can be formed by injecting electrolyte into the can (10) before or after forming the beading portion (110) in the can (10), placing the edge of the cap (40) on the beading portion (110), forming a crimping portion (120) in the can (10), and compressing the edge of the cap (10), thereby providing a welding area that is not contaminated with electrolyte at all. Due to this, an additional cleaning process for the welding process of the welding portion (50) may not be required during the manufacturing process of the battery cell (1), so that the manufacturing process can be simplified.

[0186] This eliminates the need for tack welding and the electrolyte cleaning process, improving process time. Furthermore, the use of the crimping process prevents cap lifting even when tolerances exist between components, easing the inspection process by eliminating the need for strict tolerance management. Furthermore, the resulting reduction in defective parts lowers component costs, thereby lowering overall battery cell manufacturing costs.

[0187] Therefore, the battery cell (1) according to one embodiment of the present invention can have both the advantages of the crimping sealing method and the welding sealing method by including the crimping portion (120) of the can (10) and the welding portion (50) as components. Furthermore, since double sealing is possible through the crimping portion (120) and the welding portion (50), the quality of the battery cell (1) can be improved. Hereinafter, the welding sealing method according to the present embodiment will be described in detail.

[0188]

[0189] FIG. 21 is a drawing showing the penetration depth of the welded portion (50) of the battery cell (1) according to one embodiment of the present invention, and FIGS. 22 and 23 are drawings showing the welding form of the welded portion (50) of the battery cell (1) according to one embodiment of the present invention.

[0190] Referring to FIG. 21, the welded portion (50) may include at least one of a first welded portion (S1) and a second welded portion (S2).

[0191] The first welding portion (S1) can be welded along the end of the folded area of ​​the crimping portion (120) of the can (10). Accordingly, welding can be sufficiently performed near the end of the folded area of ​​the crimping portion (120) of the can (10) and the edge of the upper surface of the cap (40), thereby ensuring weldability, stability, and durability.

[0192] At this time, the first welding portion (S1) can be welded at once to at least a portion of the externally exposed area of ​​the direction changing portion (326) of the second collector plate (32), as seen in FIGS. 18 and 19. Thus, with one welding process, the electrical connection and sealing fixation of the can (10), the collector plate (30), and the cap (40) can be performed at once, thereby reducing the welding man-hours.

[0193] The crimping portion (120) of the can (10) can provide a wide contact area to the upper surface of the battery cell (1). Accordingly, a second welding portion (S2) can be additionally formed radially outside the first welding portion (S1). That is, the welding portion (150) can be provided in multiple numbers. Accordingly, electrical connection and sealing fixation can be performed in an overlapping manner through multiple welding processes.

[0194] The second welding portion (S2) may be welded along the vicinity of the end of the bent region of the crimping portion (120) of the can (10). As a result, the compression portion by the crimping portion (120) of the can (10) may be welded along a wider area, thereby providing a more solid joint or additional joint, thereby further strengthening the sealing force by welding.

[0195] At this time, the welding portion (50) may be provided in multiple pieces in the bent area of ​​the crimping portion (120) of the can (10), and the second welding portion (S2) may have a different penetration depth from the second welding portion (51). For example, the penetration depth (d1) of the first welding portion (S1) may be formed relatively deeper so that the crimping portion (120) of the can (10) and the direction changing portion (326) of the second current collector (32) can be joined. In addition, the penetration depth (d2) of the second welding portion (S2) may be formed relatively shallower than the penetration depth (d1) of the first welding portion (S1) so that the crimping portion (120) of the can (10) and the current collector (30) can be welded together at the same time while being joined near the upper surface edge of the cap (40). In addition, the second welding portion (S2) can be welded only with the crimping portion (120) and the current collector plate (30), and the penetration depth (d3) can be formed relatively shallower than the penetration depth (d1) of the first welding portion (S1).

[0196] That is, since excessive melting may weaken or deform the weld (50), by appropriately controlling the penetration depth of each required weld (50), the optimal welding strength of the weld (50) can be secured, and durability and reliability can be increased. In addition, when a plurality of welds (150) at different locations are provided, even if a weld joint occurs in one weld, if the other welds are welded within the intended normal range, a welding defect as a whole can be prevented.

[0197] Referring to FIGS. 22 and 23, the welding portion (50) is provided in multiple pieces, and at least one of the welding portions (50) may have a closed-curve welding shape. For example, one of the welding portions (50) may have a closed-curve welding shape in a portion of the direction-changing portion (326) of the second current collector (32) exposed to the outside and an end portion of a folded area of ​​the crimping portion (120) of the can (10). In addition, one of the welding portions (50) may have a closed-curve welding shape or a welding shape spaced apart at a certain interval along an outer periphery near the end portion of the folded area of ​​the crimping portion (120) of the can (10).

[0198] In this way, the influence of welding heat by the above welding part (50) can be further minimized, and by providing multiple welding parts (50), the electrical connection and sealing force can be further strengthened.

[0199] In addition, the welding position or penetration depth of the welding portion (50) may vary depending on the shape of the current collector plate (30). As described above, the can connection portion (324) of the current collector plate (30) may be interposed between the edge of the cap (40) and the crimping portion (120) of the can (10), and may have various shapes to provide sealing force without a sealing gasket for sealing. Accordingly, the number, position, penetration depth, etc. of the welding portion (50) may be appropriately modified depending on the shape of the current collector plate (30).

[0200] Therefore, the battery cell (1) according to one embodiment of the present invention can reduce welding defects and further improve electrical connection performance and sealing performance.

[0201]

[0202] Fig. 24 is a flowchart of a manufacturing process of a battery cell (1) according to one embodiment of the present invention. Hereinafter, with reference to Fig. 24, an example of a method for manufacturing the above-described battery cell (1) will be described.

[0203] First, prepare the can (10) with one end being an open end, and prepare the electrode assembly (20) with the first collector plate (31) and the second collector plate (32) welded to both ends.

[0204] Next, the electrode assembly (20) is accommodated in the can (10) (S1).

[0205] Next, the side of the can (10) is beaded to form a beading portion (110) (S2). At this time, the beading portion (110) of the can (10) may be formed near the open end of the can (10). Hereinafter, a redundant description of the beading portion (110) described above with reference to FIGS. 13 and 14 will be omitted.

[0206] At this time, the electrolyte can be poured into the can (10) before or after forming the beading portion (110) of the can (10). Accordingly, even if the electrolyte is poured into the can (10) before the welding process for sealing the can (10), there is no room for the welding portion of the can (10) to be contaminated with the electrolyte, so welding is possible even without a prior cleaning process.

[0207] After the electrolyte solution is poured, the open end of the can (10) is covered with the cap (40) (S3).

[0208] Next, the open end of the can (10) is crimped to form the crimping portion (120) (S4).

[0209] By the above-described crimping process, the second collector plate (32) is pressed and interposed between the edge of the cap (40) and the crimping portion (120) of the can (10). That is, the primary sealing of the present invention is performed. Hereinafter, a redundant description of the second collector plate (32) described above with reference to FIGS. 15 to 19 will be omitted.

[0210] At this time, a welding area that is not contaminated with electrolyte is provided on the upper surface of the crimping portion (120) of the can (10) and the upper surface of the can (10).

[0211] Next, the welding portion (150) that welds the crimping portion (120) of the can (10) and the cap (40) is formed (S5). The welding portion (150) can be formed in an area where the upper portion of the cap (40) and the can (10) overlap, that is, the secondary sealing of the present invention is performed. Thus, in the method for manufacturing a battery cell (1) as an embodiment of the present invention, double sealing by crimping processing and welding processing is performed, thereby securing a stronger sealing force. The welding may be, for example, laser welding, but the joining method is not necessarily limited thereto.

[0212] At this time, the welding part (50) and the second collector plate (32) can be welded together.

[0213] In addition, the welded portion (50) may be a plurality of portions including the first welded portion (S1) and the second welded portion (S2). In this case, the first welded portion (S1) may be formed after the second welded portion (S2) is formed, or the second welded portion (S2) may be formed after the first welded portion (S1) is formed. In addition, the first welded portion (S1) and the second welded portion (S2) may be formed simultaneously.

[0214] Here, the first welded portion (S1) and the second welded portion (S2) may have the same or different penetration depths. Hereinafter, a duplicate description of the welded portion (150) described above with reference to FIGS. 20 to 23 will be omitted.

[0215] Accordingly, the battery cell (1) according to one embodiment of the present invention can provide a design that increases the energy density per unit volume of the battery cell (1) while preventing welding heat from affecting the performance of the battery cell (1) by grafting a crimping fixing method onto the welding sealing method of the can (10) and the cap (40) for sealing.

[0216]

[0217] FIG. 25 is a schematic drawing of a battery pack (P) equipped with a battery cell (1) according to one embodiment of the present invention, and FIG. 26 is a schematic drawing of a vehicle (V) equipped with a battery pack (P) according to one embodiment of the present invention.

[0218] A battery pack (P) according to one embodiment of the present invention may further include various other components of a battery pack (P) known at the time of filing of the present invention. For example, a battery pack (P) according to one embodiment of the present invention may further include components such as a current sensor, a fuse, and a service plug.

[0219] In addition, the vehicle (V) according to one embodiment of the present invention may include one or more battery packs (P) according to the present invention. In addition to the battery pack (P), the vehicle (V) according to one embodiment of the present invention may further include various other components included in the vehicle (V). For example, the vehicle (V) according to one embodiment of the present invention may further include a body, a motor, a control device such as an ECU (electronic control unit), etc., in addition to the battery pack (P) according to one embodiment of the present invention.

[0220] In addition, the battery pack (P) according to one embodiment of the present invention can be applied to various types of energy storage devices or power sources, and it is of course also possible to be equipped with other devices, apparatuses, and facilities, such as energy storage systems that use secondary batteries, in addition to the automobile (V).

[0221]

[0222] As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited thereto, and various modifications and variations are possible by a person having ordinary skill in the art to which the present invention pertains within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below.

[0223] [Explanation of symbols]

[0224] 1: Battery cell

[0225] 10: Can

[0226] 11: Side wall member

[0227] 110: Bidding Department

[0228] 111: Lower slope depression

[0229] 112: Upper slope depression

[0230] 120: Crimping section

[0231] 12: Flooring

[0232] 13: First electrode terminal (positive terminal)

[0233] 14: Gasket

[0234] 15: Second electrode terminal

[0235] 16: Insulator

[0236] 20: Electrode assembly

[0237] 21: First electrode

[0238] 22: Second electrode

[0239] 23: Metal foil

[0240] 24: Active material layer

[0241] 25: Maintenance Department

[0242] 26: Ministry of Immigration

[0243] 27: Electrode tab (notching tab)

[0244] 28: Membrane

[0245] 31: First collector plate (positive collector plate)

[0246] 311: Terminal connection

[0247] 312: Ringbu

[0248] 313: Electrode connection

[0249] 32: Second collector plate (negative collector plate)

[0250] 321: Inner ring

[0251] 322: Hall

[0252] 323: Electrode connection

[0253] 324: Can connector

[0254] 325: Extroverted Extension Department

[0255] 326: Direction change section

[0256] 40: Cap

[0257] 50: Welding

[0258] S1: First weld

[0259] S2: Second weld

[0260] P: Battery pack

[0261] V: Car

[0262] L: Laser

Claims

1. As a battery cell, A can having an open end on one side; An electrode assembly accommodated inside the can; A current collector plate electrically connected to the above electrode assembly; a cap covering the above open end; and The above can and the above cap include a welded portion joined by welding, The above can, A bead portion pressed inwardly along the circumference near the open end on the side of the can; and A battery cell characterized in that it has a crimping portion that is bent inwardly along the periphery of the open end at the side of the can and wraps and secures the edge of the cap.

2. In paragraph 1, The above beading part, A lower slanted depression formed so as to face downward as it goes inward; and A battery cell characterized by including an upper inclined recessed portion connected to the lower inclined recessed portion and formed so as to face upward as it goes inward.

3. In paragraph 2, The above beading part, A battery cell characterized in that the lower inclined recessed portion and the upper inclined recessed portion form a certain angle and have an inclined shape as a whole.

4. In paragraph 1, The above collector plate, It includes an outwardly extending portion formed so as to face upward as it goes outward, A battery cell, characterized in that the above-mentioned outward extension portion is in contact with the above-mentioned beading portion.

5. In paragraph 1, The above collector plate, A battery cell characterized by including a can connecting portion interposed between the edge of the cap and the crimping portion.

6. In paragraph 5, The above can connection part is, A battery cell characterized by having a ring shape or a closed loop shape.

7. In paragraph 1, The above collector plate, Including a direction-changing portion bent inwardly, A battery cell, characterized in that the direction-changing portion is interposed between the upper surface of the cap and the lower surface of the folded area of ​​the crimping portion.

8. In paragraph 7, The above direction changing part is, A battery cell, characterized in that at least some area extends further inwardly than the folded area of ​​the crimping portion.

9. In paragraph 1, The above welding part, A battery cell characterized in that the seam is welded in the folded area or the outermost area of ​​the above-mentioned crimping portion.

10. In paragraph 1, The above welding part, A battery cell characterized in that it is welded together with at least a portion of the above current collecting plate.

11. In paragraph 1, The above welding part, A first welded portion welded along the end of the folded area of ​​the above-mentioned clamping portion; and A battery cell characterized by including at least one of the second welding portions welded along the vicinity of an end portion of a folded area of ​​the above-mentioned crimping portion.

12. In paragraph 1, The above welding part, A battery cell characterized by having a plurality of cells, each having a different penetration depth.

13. In paragraph 1, The above welding part, A battery cell, characterized in that it is provided in multiple pieces, at least one of which has a closed curve welded shape.

14. In paragraph 1, The above welding part, A battery cell characterized in that the welding position or penetration depth is variable depending on the shape of the above-mentioned collector plate.

15. A battery pack comprising a battery cell according to any one of claims 1 to 14.

16. A motor vehicle equipped with at least one battery pack according to paragraph 15.

17. A method for manufacturing a battery cell, A step of accommodating an electrode assembly connected to a collector plate into a can; A step of beading the side of the can; A step of inserting a cap into the open end of the can; A step of sealing by crimping the open end of the can; and A method for manufacturing a battery cell, characterized by including a step of double sealing by welding an area where the upper portion of the cap and the can overlap.

18. In paragraph 17, The manufacturing method of the above battery cell is, A method for manufacturing a battery cell, characterized in that it includes a step of injecting an electrolyte into the interior of the can before or after the step of performing the beading process.

19. In paragraph 17, The above double sealing step is: A method for manufacturing a battery cell, characterized in that the above-mentioned current collector plate, the cap, and the can are welded together.

20. In any one of paragraphs 17 to 19, The above double sealing step is: A method for manufacturing a battery cell, characterized in that seam welding is performed so that the penetration depths are the same or different in multiple welding areas.

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