Battery cell, battery pack, and vehicle comprising same

Abstract

A battery cell according to the present invention comprises: an electrode assembly provided by being wound around the central axis of a winding center hole with a separator interposed between a first electrode and a second electrode; a cell housing having the electrode assembly accommodated therein and having an opening formed on one side thereof; a can lid covering the opening; and a current collector having a first coupling portion coupled to the electrode assembly and a second coupling portion coupled to the can lid, wherein the second coupling portion is spaced apart from the electrode assembly.

Description

Battery cells, battery packs and vehicles containing the same

[0001] The present invention relates to a battery cell, a battery pack, and a vehicle including the same, and more particularly, to a battery cell, a battery pack, and a vehicle including the same, which can minimize damage to an electrode assembly.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0109954, filed August 16, 2024, and Korean Patent Application No. 10-2025-0107706, filed August 5, 2025, the entire contents of which are incorporated herein by reference.

[0003] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has rapidly increased, and the development of electric vehicles, energy storage batteries, robots, and satellites has been in full swing, research on high-performance secondary batteries capable of repeated charging and discharging is actively being conducted.

[0004] Currently commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium-ion batteries. Among these, lithium-ion batteries are attracting attention for their advantages over nickel-based batteries: virtually no memory effect, free charging and discharging, a very low self-discharge rate, and high energy density.

[0005] These lithium-ion secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. Furthermore, the lithium-ion secondary battery comprises an electrode assembly comprising positive and negative plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between them, and an outer packaging material that seals and houses the electrode assembly together with an electrolyte.

[0006] Meanwhile, lithium-ion secondary batteries can be classified into pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of aluminum laminate sheet, and can-type secondary batteries, in which the electrode assembly is housed in a metal can, depending on the shape of the battery case. Furthermore, can-type secondary batteries can be further classified into cylindrical batteries and prismatic batteries, depending on the shape of the metal can. These lithium-ion secondary batteries are assembled into a dense structure by overlapping or stacking multiple battery cells to provide high voltage and high current, and then electrically connected to form battery modules or battery packs.

[0007] Fig. 1 is a side cross-sectional view showing a portion of a conventional battery cell. Referring to Fig. 1, a conventional battery cell (1') may include an electrode assembly (10'), a cell housing (20'), a current collector (30'), and a can lid (40'). In the conventional battery cell (1'), the non-conductive portion of the electrode assembly (10') and the current collector (30') may be welded together at a first welding portion (W1'), and the can lid (40') and the current collector (30') may be welded together at a second welding portion (W2').

[0008] However, in the conventional battery cell (1'), the portion of the current collector (30') corresponding to the second welding portion (W2') and the portion of the current collector (30') corresponding to the first welding portion (W1') were positioned at the same height. That is, in the conventional battery cell (1'), the portion of the current collector (30') corresponding to the second welding portion (W2') was in contact with the electrode assembly (10') or was positioned very close to the electrode assembly (10'). Accordingly, when welding was performed at the second welding portion (W2'), the high temperature heat caused by the welding could be transferred to the electrode assembly (10') via the current collector (30'), so that the electrode assembly (10') was likely to be damaged. In particular, the separator of the electrode assembly (10') was likely to be damaged.

[0009] In addition, since the conventional battery cell (1') has a can lead (40'), a current collector (30'), and an electrode assembly (10') that are in contact with each other or are arranged very close to each other, tolerances between them can accumulate, and thus, there is a high possibility that welding defects will occur when welding the can lead (40') and the cell housing (20').

[0010] Therefore, there is an urgent need to develop a battery cell (1') that can minimize welding defects while minimizing damage to the electrode assembly (10').

[0011] The present invention was created in consideration of the above-described problems, and has as its primary purpose the provision of a battery cell, a battery pack, and an automobile including the same, which can minimize damage to an electrode assembly during the assembly process.

[0012] In addition, another purpose is to provide a battery cell, a battery pack and a vehicle including the same, which can minimize damage to the electrode assembly during the welding process of the can lead and the current collector.

[0013] In addition, another object of the present invention is to provide a battery cell, a battery pack and a vehicle including the same, which can stably support a can lead.

[0014] In addition, another purpose is to provide battery cells, battery packs and vehicles including the same with improved quality, where tolerances between each component can be effectively offset.

[0015] Another objective is to provide battery cells, battery packs and vehicles including the same with improved productivity.

[0016] Another object of the present invention is to provide battery cells, battery packs and vehicles including the same with improved assembly properties.

[0017] In addition, another object of the present invention is to provide a battery cell, a battery pack and a vehicle including the same with improved current path and increased electrical stability.

[0018] Another objective is to provide battery cells, battery packs and vehicles including the same with improved energy density.

[0019] In addition, another object of the present invention is to provide a battery cell, a battery pack and a vehicle including the same, in which the possibility of welding defects between the can lead and the cell housing is minimized.

[0020] The technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

[0021] A battery cell according to the present invention comprises: an electrode assembly wound around a central axis of a winding center hole with a separator interposed between first and second electrodes; a cell housing in which the electrode assembly is accommodated therein and an opening formed at one side; a can lid covering the opening; and a current collector having a first coupling portion coupled to the electrode assembly and a second coupling portion coupled to the can lid, wherein the second coupling portion is spaced apart from the electrode assembly.

[0022] The above second connecting portion can be welded to the can lid.

[0023] The second connecting portion may be configured to apply elastic restoring force to the can lid when pressurized by the can lid.

[0024] The above can lead may be configured in a form that allows it to be inserted into the inside of the cell housing through the opening.

[0025] The above can lead can be force-fitted to the cell housing.

[0026] The above second connecting portion can be manufactured by bending a portion of the entire body.

[0027] The above-mentioned collector may further include a bridge portion connecting the first coupling portion and the second coupling portion; and a first inclined portion connecting the second coupling portion and the bridge portion, but formed to be inclined.

[0028] The angle between the first slope and the bridge may be formed as an obtuse angle.

[0029] The above-mentioned collector may further include a peripheral portion formed to surround at least a portion of the first coupling portion at an edge.

[0030] The above-mentioned collector may further include a second inclined portion that connects the second connecting portion and the peripheral portion and is formed to be inclined.

[0031] The above second slope and the above circumferential portion may be configured to be continuous throughout the entire circumferential direction.

[0032] The angle between the second slope and the circumference can be formed as an obtuse angle.

[0033] The above-mentioned collector may be configured so as not to come into contact with the cell housing.

[0034] The above-mentioned collector may have a plurality of the second coupling portions.

[0035] The above-mentioned collector may have three of the second coupling parts.

[0036] The above can lid can be welded to the cell housing.

[0037] A battery pack according to the present invention comprises at least one battery cell according to the present invention.

[0038] A vehicle according to the present invention comprises at least one battery pack according to the present invention.

[0039] According to the present invention, a battery cell, a battery pack, and a vehicle including the same can be provided, in which a second connecting portion of a current collector is spaced apart from an electrode assembly, thereby minimizing damage to the electrode assembly during an assembly process.

[0040] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same can be provided, which can minimize damage to the electrode assembly during the welding process of the can lead and the current collector, as the second connecting portion is spaced apart from the electrode assembly.

[0041] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same can be provided, wherein the entire body can stably support a can lead.

[0042] In addition, according to one aspect of the present invention, tolerances between each component can be effectively offset, thereby providing a battery cell, a battery pack, and a vehicle including the same with improved quality.

[0043] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same with improved productivity can be provided.

[0044] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same with improved assembly can be provided.

[0045] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same can be provided with improved electrical stability due to improved current pass.

[0046] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same with improved energy density can be provided.

[0047] In addition, according to one aspect of the present invention, a battery cell, a battery pack, and a vehicle including the same can be provided in which the possibility of welding defects between a can lead and a cell housing is minimized.

[0048] The effects of the present invention are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

[0049] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0050] Figure 1 is a cross-sectional side view showing a portion of a conventional battery cell.

[0051] Figure 2 is a perspective view showing the overall appearance of a battery cell according to one embodiment of the present invention.

[0052] Figure 3 is a perspective view of Figure 2 viewed from a different direction.

[0053] FIG. 4 is a cross-sectional side view showing the overall appearance of a battery cell according to one embodiment of the present invention.

[0054] Fig. 5 is a perspective view showing the can lid in Fig. 2 in an exploded manner.

[0055] Figure 6 is a perspective view showing a collector according to one embodiment of the present invention.

[0056] Figure 7 is a plan view showing a collector according to one embodiment of the present invention.

[0057] FIG. 8 is a cross-sectional side view showing a portion of a battery cell according to one embodiment of the present invention.

[0058] Figure 9 is a cross-sectional side view showing the welds in Figure 8 further illustrated.

[0059] Figure 10 is a perspective view showing an enlarged view of area B of Figure 6.

[0060] FIG. 11 is a drawing showing a battery pack according to one embodiment of the present invention.

[0061] Figure 12 is a drawing showing a vehicle according to one embodiment of the present invention.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] In this specification, unless otherwise specified, the X-axis and Y-axis directions may be left-right and front-back directions, or front-back and left-right directions, respectively, and the Z-axis direction orthogonal to the XY plane may be an up-down direction (vertical direction).

[0066]

[0067] FIG. 2 is a perspective view showing the overall appearance of a battery cell according to one embodiment of the present invention, FIG. 3 is a perspective view of FIG. 2 viewed from another direction, and FIG. 4 is a side cross-sectional view showing the overall appearance of a battery cell according to one embodiment of the present invention.

[0068] Referring to FIGS. 2 to 4, a battery cell (1) according to one embodiment of the present invention may include an electrode assembly (10), a cell housing (20), a can lead (40), and a current collector (30).

[0069] The battery cell (1) may be a secondary battery configured to be rechargeable. The battery cell (1) may be a cylindrical battery.

[0070] The electrode assembly (10) may include an electrode (11) and a separator (12). The electrode (11) may include electrodes (11) having different polarities. Specifically, the electrode (11) may include a first electrode (11a) and a second electrode (11b). The first electrode (11a) may have a first polarity, and the second electrode (11b) may have a second polarity that is opposite to the first polarity. For example, the first polarity may be a negative electrode and the second polarity may be an positive electrode. The separator (12) may be interposed between the electrodes (11) having different polarities. The separator (12) may be interposed between the first electrode (11a) and the second electrode (11b). The separator (12) may be an insulator.

[0071] The electrode assembly (10) may have a jelly-roll structure. That is, the electrode assembly (10) may be manufactured by winding a laminate formed by laminating a first electrode (11a) and a second electrode (11b) in sheet form at least once with a separator (12) interposed between them, around the central axis (A) of the winding center hole (C). The jelly-roll structure may be applied to the present invention without limitation as long as it is a structure known in the art.

[0072] The electrode (11) may include a conductive metal material. For example, the electrode (11) may include either copper (Cu) or aluminum (Al). In particular, the first electrode (11a) may include copper, and the second electrode (11b) may include aluminum.

[0073] Each electrode (11) may have a holding portion and a non-holding portion (13). The holding portion may be a portion where an active material layer is laminated on at least one surface of the electrode (11). For example, a negative electrode active material may be laminated on the holding portion of the first electrode (11a), and a positive electrode active material may be laminated on the holding portion of the second electrode (11b).

[0074] The non-conductive portion (13) may be a portion of the electrode (11) on which no active material is laminated. The electrode (11) may have a predetermined length and width, and the non-conductive portion (13) may be formed on one long side of the electrode (11).

[0075] At least a portion of the non-conductive portion (13) may be exposed to the outside of the separator (12). The non-conductive portion (13) may be used as a tab of the electrode (11).

[0076] Among the non-coated portions (13), the non-coated portion (13) of the first electrode (11a) may be referred to as the first non-coated portion (13a), and the non-coated portion (13) of the second electrode (11b) may be referred to as the second non-coated portion (13b). The first non-coated portion (13a) may be arranged at the top (e.g., +Z-direction end) of the electrode assembly (10), and the second non-coated portion (13b) may be arranged at the bottom (e.g., -Z-direction end) of the electrode assembly (10).

[0077] The electrode (11) may have a plurality of foil tabs. The plurality of foil tabs may be provided on the non-coated portion (13). The foil tabs may be exposed to the outside of the separator (12). The plurality of foil tabs may be arranged in a row from the winding center hole (C) side toward the outer periphery. The plurality of foil tabs may be formed by at least one notching portion formed by notching processing.

[0078] The electrode (11) may have an insulating coating portion. The insulating coating portion may be arranged at the boundary between the non-conductive portion (13) and the retaining portion. The insulating coating portion may be provided when the electrode (11) is the second electrode (11b), and may prevent the retaining portions of the second electrode (11b) and the first electrode (11a) from contacting each other.

[0079] The cell housing (20) may be configured to accommodate an electrode assembly (10). The electrode assembly (10) may be accommodated inside the cell housing (20). The cell housing (20) may have a receiving space in which the electrode assembly (10) is accommodated. The cell housing (20) may be provided in a cylindrical shape with an empty interior to accommodate the electrode assembly (10), for example. The cell housing (20) may include a conductive metal material.

[0080] The cell housing (20) may have an opening (21) formed on one side. The opening (21) may be formed on one axial side of the cell housing (20). Here, the axial direction may be understood as the central axis of the winding center hole. The electrode assembly (10) may be inserted through the opening (21) and accommodated in the cell housing (20). The opening (21) may be provided, for example, on the upper side of the cell housing (20).

[0081] Meanwhile, the cell housing (20) may be provided with a closed portion (22) formed on the opposite side of the open portion (21). A terminal (50) may be arranged on the closed portion (22) side. A detailed description of the closed portion (22) and the terminal (50) will be provided later.

[0082] The can lid (40) can cover the opening (21). The can lid (40) can be coupled to the end of the cell housing (20) on the opening (21) side. The can lid (40) can cover the electrode assembly (10).

[0083] The can lead (40) can be inserted into and joined to the opening (21). Specifically, the can lead (40) can be inserted into the opening (21) in a direction from one axial side toward the electrode assembly (10) and joined to the cell housing (20). The can lead (40) can be arranged at the outermost portion of one axial side of the cell housing (20) and can form a part of the outer shape of the battery cell (1).

[0084] The current collector (30) can be connected to the electrode assembly (10) and the can lead (40), respectively. The current collector (30) can be electrically connected to the electrode assembly (10) and the can lead (40), respectively.

[0085] The current collector (30) may include a first current collector (30a) and a second current collector (30b). The first current collector (30a) may be electrically connected to the first electrode (11a) (11a). The first current collector (30a) may be welded and joined to the first non-stick portion (13a). The first current collector (30a) may be a negative current collector (30). The second current collector (30b) may be electrically connected to the second electrode (11b). The second current collector (30b) may be welded and joined to the second non-stick portion (13b). The second current collector (30b) may be a positive current collector (30).

[0086] Below, the description of the current collector (30) can be commonly applied to both the first current collector (30a) and the second current collector (30b) unless otherwise specified.

[0087]

[0088] FIG. 5 is a perspective view showing the can lead in FIG. 2 in an exploded manner, FIG. 6 is a perspective view showing a current collector according to an embodiment of the present invention, FIG. 7 is a plan view showing a current collector according to an embodiment of the present invention, FIG. 8 is a side cross-sectional view showing a portion of a battery cell according to an embodiment of the present invention, and FIG. 9 is a side cross-sectional view showing welded portions further shown in FIG. 8.

[0089] Hereinafter, with further reference to FIGS. 5 to 9, a battery cell (1) according to one embodiment of the present invention will be described in detail.

[0090] The entire body (30) may have a first coupling part (31) and a second coupling part (32).

[0091] The first coupling portion (31) can be coupled to the electrode assembly (10). The first coupling portion (31) can be electrically connected to the electrode assembly (10). The first coupling portion (31) can be coupled to the uncoated portion (13) of the electrode assembly (10). The first coupling portion (31) can be in contact with the electrode assembly (10) or the uncoated portion (13).

[0092] Meanwhile, the first connecting portion (31) may be a portion of a current collector (30) configured to be welded to the electrode assembly (10) to the non-conductive portion (13). The first connecting portion (31) and the electrode assembly (10) to the non-conductive portion (13) may be in surface contact with each other, and a first welding portion (W1) that is welded may be formed at each portion in surface contact. When the first connecting portion (31) is welded to the electrode assembly (10) to the non-conductive portion (13), improved bondability and improved current-conducting area between them can be expected.

[0093] Meanwhile, the first coupling portion (31) may include at least one extension portion (33). The extension portion (33) may be a portion that extends radially outward from the first coupling portion (31). When the first coupling portion (31) includes the extension portion (33), a wider coupling area between the first coupling portion (31) and the electrode assembly (10) can be secured.

[0094] The second coupling portion (32) may be a portion of the current collector (30) configured to be coupled with the can lid (40). The second coupling portion (32) may be electrically connected to the can lid (40). The second coupling portion (32) may be in face-to-face contact with the can lid (40). The second coupling portion (32) may be in surface contact with the can lid (40).

[0095] For example, with reference to FIG. 8, a can lead (40) may be arranged on the upper side or +Z direction side of the second coupling portion (32), and the upper surface of the second coupling portion (32) may be in surface contact with a portion of the lower surface of the can lead (40). At this time, among the outer peripheral portion (35) of the can lead (40), a portion facing the second coupling portion (32) may be referred to as a first facing portion (42), and the upper surface of the second coupling portion (32) may be in surface contact with the first facing portion (42). When the second coupling portion (32) and the can lead (40) are in surface contact, not only can the second coupling portion (32) stably support the can lead (40), but also the current carrying area between the second coupling portion (32) and the can lead (40) increases, so that the current path and electrical stability may be improved.

[0096] The second connecting portion (32) may have a flat shape. For example, the second connecting portion (32) may have a flat shape parallel to the XY plane. In addition, the portion of the can lid (40) that is connected to the second connecting portion (32) may also have a flat shape. For example, the first facing portion (42) may have a flat portion. In this case, surface contact between the second connecting portion (32) and the can lid (40) can be effectively achieved.

[0097] The second coupling portion (32) may be spaced apart in the axial direction from the electrode assembly (10). The second coupling portion (32) may be spaced apart from the uncoated portion (13) of the electrode assembly (10). For example, the bottom surface of the second coupling portion (32) may be spaced apart from the upper portion of the electrode assembly (10) to the uncoated portion (13) in the +Z direction. The second coupling portion (32) may be spaced apart from the electrode assembly (10) to the uncoated portion (13) by a predetermined height (h).

[0098] In the battery cell (1) according to the present invention, the second connecting portion (32) of the current collector (30) can be spaced apart from the electrode assembly (10), so that damage to the electrode assembly (10) caused by the second connecting portion (32) can be minimized. Specifically, in the case of the conventional battery cell (1') shown in Fig. 1, when the can lead (40') is inserted into the opening of the cell housing (20'), the current collector (30') is pressed by the can lead (40'), and the electrode assembly (10') can also be pressed and damaged by the pressed current collector (30'). However, in the battery cell (1) according to the present invention, even if the second connecting portion (32) is pressed by the can lead (40), the second connecting portion (32) is spaced apart from the electrode assembly (10), so that damage to the electrode assembly (10) caused by the second connecting portion (32) can be minimized.

[0099]

[0100] The second joint (32) can be welded to the can lid (40). A second welded portion (W2) can be formed at each portion where the second joint (32) and the can lid (40) come into surface contact with each other. When the second joint (32) is welded to the can lid (40), improved bondability and increased current-carrying area can be expected.

[0101] The battery cell (1) according to the present invention can minimize damage to the electrode assembly (10) due to high temperature welding heat generated during the welding process of the second connecting portion (32) and the can lead (40) since the second connecting portion (32) of the current collector (30) can be spaced apart from the electrode assembly (10). Specifically, in the case of the conventional battery cell (1') shown in FIG. 1, the current collector (30') is very close to or in contact with the electrode assembly (10') or the non-conductive portion, so that when the can lead (40') and the current collector (30') are penetrated and welded, the high temperature welding heat can be directly transferred to the electrode assembly (10') via the current collector (30'), so that there is a high possibility that the electrode assembly (10') is damaged, and in particular, there is a high possibility that the separator is damaged. However, in the battery cell (1) according to the present invention, during the welding process between the can lead (40) and the second joint (32), the second joint (32) is spaced apart from the electrode assembly (10), so that high-temperature welding heat can be prevented from being directly transferred to the electrode assembly (10) through the second joint (32), thereby minimizing damage to the electrode assembly (10) due to the high-temperature welding heat.

[0102]

[0103] The second connecting portion (32) may be configured to apply elastic restoring force to the can lid (40) when pressurized by the can lid (40). That is, the second connecting portion (32) may function like a spring.

[0104] For example, when the can lid (40) is inserted into the cell housing (20) and the can lid (40) presses the second coupling portion (32) in the axial direction, the peripheral portion of the second coupling portion (32), which is a part of the current collector (30), may be deformed by the can lid (40). The deformation may be elastic deformation. When the peripheral portion of the second coupling portion (32) is deformed in this way, the second coupling portion (32) can apply an elastic restoring force to the can lid (40) in the opposite direction to the direction in which the can lid (40) presses the second coupling portion (32). For example, when the can lid (40) presses the second coupling portion (32) downward or in the -Z direction, the second coupling portion (32) can apply an elastic restoring force toward the can lid (40) upward or in the +Z direction.

[0105] In the above, the peripheral portion of the second connecting portion (32) may be, for example, the first inclined portion (36) and / or the second inclined portion (37) described below.

[0106] Therefore, when the peripheral portion of the second connecting portion (32) is deformed by the can lid (40), the second connecting portion (32) can apply elastic restoring force to the can lid (40), and as a result, the can lid (40) can be supported by being pressed by the second connecting portion (32).

[0107] Meanwhile, in order for the can lid (40) to press the second joint (32), a separate device such as a jig may press the can lid (40) toward the second joint (32). Alternatively, as described below, when the can lid (40) is forcefully fitted to the cell housing (20), the can lid (40) may be fixed to the cell housing (20) and press the second joint (32).

[0108] The peripheral portion of the second connecting portion (32) may include an elastic material to have elasticity. For example, the second connecting portion (32) and the current collector (30) may include a metal material.

[0109] As described above, when the second connecting portion (32) supports the can lid (40) by applying elastic restoring force, the can lid (40) and the second connecting portion (32) can be strongly pressed against each other, so that the current collector (30) can stably support the can lid (40).

[0110] In the case of a conventional battery cell (1'), tolerances between the can lead (40'), the current collector (30'), and the electrode assembly (10'), as well as between the current collector (30') and other current collectors (30') and other components, could accumulate, and due to these accumulated tolerances, when welding the can lead (40') and the cell housing (20'), a step could occur between the open end of the cell housing (20') and the can lead (40'). Due to this, there was a high possibility of welding defects occurring when welding the can lead (40') and the cell housing (20'). For example, when welding the can lid (40') and the cell housing (20') in a state where the can lid (40') protrudes further outward from the cell housing (20') than the open end of the cell housing (20') due to the accumulated tolerances as described above, the contact surface area between the can lid (40') and the cell housing (20') may not be sufficiently formed, and thus the welding strength may not be sufficiently formed.

[0111] However, since the battery cell (1) according to the present invention can easily deform the peripheral portion of the second connecting portion (32), the tolerances between the respective components of the battery cell (1) can be effectively offset. As a result, the battery cell (1) according to the present invention can sufficiently insert the can lead (40) into the cell housing (20) by deforming the peripheral portion of the second connecting portion (32) without putting a strain on the electrode assembly (10), thereby improving the quality of the battery cell (1). In addition, since the contact surface area between the can lead (40) and the cell housing (20) can be secured to the maximum, the possibility of welding defects occurring when welding the can lead (40) and the cell housing (20) can be significantly reduced.

[0112]

[0113] The can lid (40) may be configured in a form that allows it to be inserted into the inside of the cell housing (20) through the opening (21). That is, the can lid (40) may not be configured to be placed on the end of the cell housing (20) on the opening (21) side, but may be configured so that at least a portion of it can be inserted into the end of the cell housing (20) on the opening (21) side.

[0114] For example, both the inner surface of the cell housing (20) and the outer peripheral portion of the can lid (40) may be formed to extend in line with the direction in which the can lid (40) is inserted into the cell housing (20). For example, with reference to FIG. 8, both the inner surface of the cell housing (20) and the outer peripheral portion of the can lid (40) may be formed to extend in the vertical direction or the Z-axis direction along the axial direction.

[0115] In this case, when the can lid (40) is inserted into the cell housing (20), the outer peripheral portion of the can lid (40) and the inner surface of the cell housing (20) can be in surface contact with each other. Here, the portion of the outer peripheral portion of the can lid (40) that faces the inner surface of the cell housing (20) may be referred to as a second facing portion (43). The second facing portion (43) may have a portion that extends parallel to the inner surface of the cell housing (20). For example, the cross-section of the inner surface of the cell housing (20) may be formed to be long in the Z-axis direction, and the cross-section of the second side portion may be formed to be long and extend along the Z-axis direction.

[0116] As described above, when the can lid (40) is configured in a form that allows it to be inserted into the inside of the cell housing (20) through the opening (21), the can lid (40) can be easily inserted into the inside of the cell housing (20), and thus the can lid (40) can easily press the second connecting portion (32).

[0117]

[0118] The can lid (40) can be force-fitted to the cell housing (20). For example, before the can lid (40) is inserted into the cell housing (20), the shape of the outer peripheral portion of the can lid (40) may be formed to be similar to the shape of the opening (21), but slightly larger than the opening (21). In addition, when the can lid (40) is inserted into the cell housing (20), the shape of the outer peripheral portion of the can lid (40) and the shape of the opening (21) may correspond to each other.

[0119] For example, if the opening (21) is circular, before the can lid (40) is inserted into the cell housing (20), the outer peripheral portion of the can lid (40) may be provided in a circular shape that is slightly larger than the opening (21), and when the can lid (40) is inserted into the cell housing (20), the outer peripheral portion of the can lid (40) and the opening (21) may each have a circular shape of the same size.

[0120] The can lid (40) may have an edge portion (41). The edge portion (41) may be provided on the outer peripheral portion of the can lid (40). The edge portion (41) may have a cross-section having an approximately 'U' shape along the peripheral direction. In this case, radial deformation of the edge portion (41) can be easily formed, and thus, a forced fit of the can lid (40) can be easily formed.

[0121] The edge portion (41) may include the first facing portion (42) and the second facing portion (43) described above. Specifically, the first facing portion may constitute a radially outer portion of the edge portion (41), and the second facing portion (43) may constitute a lower portion or a -Z direction side portion of the edge portion (41).

[0122] When the can lid (40) can be force-fitted to the cell housing (20), the can lid (40) can be force-fitted to the cell housing (20), and the degree of pressure between the can lid (40) and the second joint (32) can be easily adjusted, which has the advantage of improving the assembling ability.

[0123]

[0124] The second connecting portion (32) may be manufactured by bending a portion of the current collector (30). That is, the second connecting portion (32) may have a bent structure. In addition, the current collector (30) may have an overall roughly plate-shaped shape, but only the second connecting portion (32) may be manufactured by protruding in a bent shape. The second connecting portion (32) and the current collector (30) may be manufactured as one piece.

[0125] The current collector (30) can be manufactured by processing a roughly plate-shaped member into a form having a first connecting portion (31) and a second connecting portion (32) through a cutting and bending process. For example, the current collector (30) can be manufactured by punching and pressing a single metal sheet or metal plate, thereby manufacturing it as a seamless, one-piece, processed product.

[0126] In this way, when the second connecting portion (32) is manufactured in such a way that a portion of the current collector (30) is bent, the second connecting portion (32) can have a bent structure, so that deformation of the peripheral portion of the second connecting portion (32) can be facilitated. As a result, tolerances between each component of the battery cell (1) can be effectively offset, so that the quality of the battery cell (1) can be improved.

[0127] In addition, the manufacturing process of the collector (30) can be simplified, so that the productivity of the collector (30) can be improved.

[0128] In addition, since the second connecting part (32) and the current collector (30) can be manufactured as one piece, the rigidity and reliability of the current collector (30) can be improved.

[0129]

[0130] Figure 10 is a perspective view showing an enlarged view of area B of Figure 6.

[0131] Hereinafter, with further reference to FIG. 10, a collector (30) according to one embodiment of the present invention will be described in more detail.

[0132] The collector (30) may further include a leg portion (34) and a first inclined portion (36). The leg portion (34) may connect the first coupling portion (31) and the second coupling portion (32). The first coupling portion (31) and the second coupling portion (32) may be electrically connected by the leg portion (34). The leg portion (34) may extend radially between the first coupling portion (31) and the second coupling portion (32).

[0133] The first inclined portion (36) connects the second connecting portion (32) and the leg portion (34), and may be formed to be inclined. The first inclined portion (36) may be positioned between the second connecting portion (32) and the leg portion (34). The circumferential width of the first inclined portion (36) may be formed to be the same as the circumferential width of the leg portion (34). Here, the circumferential direction may be a circumferential direction.

[0134] The first inclined portion (36) may be formed to be inclined upward from the leg portion (34) toward the second connecting portion (32). When looking at the electrode assembly (10) from the can lid (40) side, the included angle (θ1) between the first inclined portion (36) and the leg portion (34) may be an obtuse angle. That is, the included angle (θ1) between the upper surface of the first inclined portion (36) and the upper surface of the leg portion (34) may be an obtuse angle. For example, when the insertion of the can lid (40) into the cell housing (20) is completed, the included angle (θ1) may be formed to be 120 to 150 degrees (before the can lid (40) is inserted into the cell housing (20), the included angle (θ1) may be formed to be slightly smaller than 120 to 150 degrees).

[0135] When the collector (30) further includes a first inclined portion (36) configured as described above, deformation of the peripheral portion of the second connecting portion (32) becomes easier when the can lead (40) is pressed, so that tolerances between each component of the battery cell (1) can be effectively offset, and thus the quality of the battery cell (1) can be improved.

[0136] Meanwhile, the second connecting portion (32) can be formed integrally with the first inclined portion (36).

[0137]

[0138] The current collector (30) may further include a peripheral portion (35). The peripheral portion (35) may be formed to surround at least a portion of the first connecting portion (31) at the edge of the current collector (30). The peripheral portion (35) may, for example, be provided in an overall circular shape along the circumferential direction. The peripheral portion (35) may be arranged between any two second connecting portions (32), and in this case, each peripheral portion (35) may be provided in an arc shape. The peripheral portion (35) may have a predetermined width in the radial direction.

[0139] When the entire body (30) has an additional peripheral portion (35), the rigidity of the entire body (30) can be strengthened.

[0140]

[0141] The collector (30) may further include a second inclined portion (37). The second inclined portion (37) may be formed to be inclined while connecting the second connecting portion (32) and the peripheral portion (35). The second inclined portion (37) may be arranged between the second connecting portion (32) and the peripheral portion (35). When the peripheral portions (35) are arranged on both sides of the second connecting portion (32), the second inclined portions (37) may also be arranged on both sides of the second connecting portion (32). The radial width of the second inclined portion (37) may be formed to be the same as the radial width of the peripheral portion (35).

[0142] The second inclined portion (37) may be formed to be inclined upward from the circumference portion (35) toward the second connecting portion (32). When looking at the electrode assembly (10) from the can lid (40) side, the included angle (θ2) between the second inclined portion (37) and the circumference portion (35) may be an obtuse angle. That is, the included angle (θ2) between the upper surface of the second inclined portion (37) and the upper surface of the circumference portion (35) may be an obtuse angle. For example, when the insertion of the can lid (40) into the cell housing (20) is completed, the included angle (θ2) may be formed to be 120 to 150 degrees (before the can lid (40) is inserted into the cell housing (20), the included angle (θ2) may be formed to be slightly smaller than 120 to 150 degrees).

[0143] In this way, when the current collector (30) further includes a second slope (37), deformation of the peripheral portion of the second connecting portion (32) becomes easier when the can lead (40) is pressed, so that tolerances between each component of the battery cell (1) can be effectively offset, and thus the quality of the battery cell (1) can be improved.

[0144]

[0145] The second slope portion (37) and the circumferential portion (35) may be configured to be entirely continuous. Specifically, the second slope portion (37) and the circumferential portion (35) may be configured to be entirely continuous along the circumferential direction. For example, when viewed from the axial direction or the Z-axis direction, a plurality of second slope portions (37) and a plurality of circumferential portions (35) may be configured to be continuously connected to each other along the entire circumferential direction of the current collector (30).

[0146] When the collector (30) is configured as described above, the rigidity of the collector (30) can be further secured.

[0147]

[0148] By means of the second inclined portion (37) and the first inclined portion (36), the second connecting portion (32) may have a shape that protrudes in the axial direction compared to the first connecting portion (31). In this case, the second connecting portion (32) may function as a support surface on which the can lid (40) may be secured, and the second connecting portion (32), the second inclined portion (37), and the first inclined portion (36) may function as a support having vertical mobility, thereby effectively offsetting accumulated tolerances when the can lid (40) and the cell housing (20) are connected.

[0149] The circumference (35) and the first connecting portion (31) can form the same plane (for example, a plane parallel to the XY plane). The second connecting portion (32) can be spaced apart from the first connecting portion (31) in the axial direction to form a plane parallel to the first connecting portion (31). The overall shape formed by the second connecting portion (32), the first inclined portion (36), and the second inclined portion (37) can be formed as a folded structure.

[0150] Meanwhile, the radial width of the second connecting portion (32) may be formed to be larger than the radial width of the second inclined portion (37). In this case, the size or area of ​​the second connecting portion (32) may be further expanded, so that the current-carrying area between the second connecting portion (32) and the can lead (40) may be expanded, thereby improving the current path. In addition, since the size or area of ​​the second connecting portion (32) is expanded, the second connecting portion (32) may support the can lead (40) with a larger area, so that the can lead (40) may be supported more stably and firmly.

[0151] Meanwhile, the second connecting portion (32) can be formed integrally with the second inclined portion (37).

[0152] Meanwhile, the second connecting portion (32) can be formed integrally with the first inclined portion (36) and the second inclined portion (37).

[0153]

[0154] The current collector (30) may be provided with a plurality of second coupling portions (32). For example, the current collector (30) may be provided with two or more second coupling portions (32). The plurality of second coupling portions (32) may be arranged symmetrically. Specifically, the plurality of second coupling portions (32) may be arranged symmetrically with respect to the center of the current collector (30).

[0155] In this way, when the current collector (30) has a plurality of second coupling portions (32), the second coupling portions (32) can support the can lead (40) more stably and firmly. In addition, the current conducting area between the current collector (30) and the can lead (40) can be expanded, so that the current path between the current collector (30) and the can lead (40) can be further improved, thereby further increasing electrical stability.

[0156]

[0157] The entire body (30) may be provided with three second connecting parts (32).

[0158] In this way, when the current collector (30) has three second connecting portions (32), the three second connecting portions (32) can form a single plane, so that the can lid (40) can be in close contact with each of the three second connecting portions (32). Accordingly, the deviation between the respective tolerances formed between the can lid (40) and each of the second connecting portions (32) can be minimized, so that the can lid (40) can be supported more stably and firmly on the current collector (30), and as a result, the possibility of welding defects occurring when welding the can lid (40) and the current collector (30) can be significantly reduced.

[0159] Meanwhile, the three second coupling portions (32) may be arranged symmetrically. Specifically, the three second coupling portions (32) may be arranged symmetrically with respect to the center of the current collector (30). For example, when viewed in the axial direction, the three second coupling portions (32) may form each vertex of an equilateral triangle.

[0160]

[0161] In particular, referring to FIGS. 8 and 9, the current collector (30) may not be in contact with the cell housing (20). Specifically, the current collector (30) may not be in contact with the inner surface of the cell housing (20). A predetermined gap may be formed in the radial direction between the outer circumference (35) of the current collector (30) and the inner surface of the cell housing (20). In this case, the current collector (30) may not be directly coupled to the cell housing (20). The current collector (30) may be coupled to and electrically connected with the can lid (40), and the can lid (40) may be coupled to and electrically connected with the cell housing (20), and as a result, the current collector (30) may be indirectly electrically connected with the cell housing (20).

[0162] In this way, when the current collector (30) does not come into contact with the cell housing (20), deformation of the current collector (30) can be made easier. In particular, since the second connecting portion (32) can be easily moved toward the cell housing (20), a change in the gap between the second connecting portion (32) and the electrode assembly (10) can be made more easily. Accordingly, tolerances between each component of the battery cell (1) can be more effectively offset, so that the quality of the battery cell (1) can be further improved.

[0163] In addition, since the possibility of interference between the current collector (30) and the cell housing (20) is significantly reduced, there is no need to precisely adjust the concentricity between the center of the current collector (30) (particularly, the first connecting portion (31)) and the center of the electrode assembly (10) during the battery cell (1) assembly process, so that the assembly and productivity of the battery cell (1) can be improved.

[0164]

[0165] The can lid (40) can be welded to the cell housing (20). Specifically, when the can lid (40) is inserted into the opening (21) of the cell housing (20), the can lid (40) and the cell housing (20) come into contact with each other, and a third welded portion (W3) can be formed at the portion where the can lid (40) and the cell housing (20) come into contact. For example, the can lid (40) can have an outer peripheral surface of the can lid (40) come into surface contact with an inner surface of the cell housing (20), and in this state, a third welded portion (W3) can be formed between the outer peripheral surface of the can lid (40) and the inner surface of the cell housing (20).

[0166] When the can lead (40) is welded to the cell housing (20), improved bondability and increased current-carrying area can be expected.

[0167] In addition, in the case of the existing battery cell (1), the cell housing (20) could include a beading portion and a crimping portion of a recessed shape. In the existing battery cell (1), the electrode assembly (10) and the current collector (30) could be fixed by the beading portion and the crimping portion. However, the battery cell (1) according to the present invention may not include the beading portion and the crimping portion included in the existing battery cell (1). In the battery cell (1) according to the present invention, the electrode assembly (10) and the current collector (30) can be firmly and stably fixed without including the components corresponding to the beading portion and the crimping portion of the existing battery cell (1). In addition, in the battery cell (1) according to the present invention, the size of the space that the electrode assembly (10) can occupy inside the cell housing (20) increases, so that the energy density can be improved.

[0168]

[0169] Meanwhile, referring again to FIGS. 5 and 6, the can lid (40) may have an injection hole (46), and the current collector (30) may have a hole.

[0170] The injection hole (46) may be provided in a form that penetrates the can lid (40) and is in communication with the electrode assembly (10). Through the injection hole (46), the electrolyte can be easily injected into the electrode assembly (10). A hole (H) may be formed in the current collector (30). The hole (H) may be in communication with the electrode assembly (10). The hole may be in communication with the core of the electrode assembly (10). It may be understood as a winding center hole (C) having an empty space formed therein. The electrolyte injected through the injection hole (46) may pass through the hole (H) and flow into the interior of the electrode assembly (10). The hole (H) may be formed at a position corresponding to the injection hole (46). A plug (47) may be coupled to the injection hole (46). After the injection of electrolyte through the injection hole (46) is completed, a plug (47) is coupled to the injection hole (46), so that the injection hole (46) can be sealed. Various structures can be applied to the structures of the injection hole (46) and the plug (47).

[0171]

[0172] Meanwhile, referring again to FIGS. 8 and 9, the can lid (40) of the battery cell (1) according to the present invention may be provided with a vent portion (44). When the internal pressure of the battery cell (1) exceeds a preset reference value due to high-temperature venting gas generated by a thermal event occurring in the battery cell (1), the vent portion (44) may be ruptured and at least a portion thereof may be separated from the battery cell (1) and opened. When the vent portion (44) is opened, high-temperature venting gas, flames, solid discharges, etc. inside the battery cell (1) may be discharged to the outside through the opened vent portion (44). The vent portion (44) may be formed by notching at least one of the axially opposite surfaces of the can lid (40), and the notched portion may be referred to as a vent notch portion (45). The vent notch portion (45) can be formed by notching along the circumferential direction on the inside of the can lid (40).

[0173]

[0174] Meanwhile, referring again to FIGS. 3 and 4, the battery (1) according to the present invention will be described in more detail.

[0175] The cell housing (20) may have a closing portion (22) as described above. The closing portion (22) may be formed on the other side or lower side (-Z direction side) of the cell housing (20). The closing portion (22) may be configured in a closed form. A terminal (50) may be arranged in the closing portion (22). The terminal (50) may be configured to penetrate the closing portion (22) and at least a portion thereof be exposed to the outside. The terminal (50) may be provided in a rivet form. The terminal (50) may be electrically connected to the second electrode (11b) and may have a second polarity. The terminal (50) may be joined to the second current collector (30b) by welding or the like. The terminal (50) may be configured as a positive terminal (50).

[0176] The closing portion (22) may have a first polarity. As described above, the cell housing (20) may be electrically connected to the first electrode (11a) and may have a first polarity. An insulating gasket may be placed between the closing portion (22) and the terminal (50) to insulate them.

[0177] An insulator configured to insulate the closing member (22) and the second collector (30b) may be placed between them. The insulator may also be configured to insulate the electrode (11) assembly and the cell housing (20) from each other.

[0178]

[0179] Meanwhile, preferred examples of the battery (1) according to the present invention have been described above. The technical concept of the present invention is not limited to these examples and may include combinations of any two or more of them.

[0180]

[0181] FIG. 11 is a drawing showing a battery pack according to one embodiment of the present invention.

[0182] Referring to FIG. 11, a battery pack (3) according to the present invention may include at least one battery (1) according to the present invention. The battery pack (3) may include a pack case (2) that accommodates at least one battery (1).

[0183] In the drawing, for the convenience of illustration, components such as bus bars, cooling units, and external terminals for electrical connection of batteries (1) are omitted. The structure of multiple batteries (1) for manufacturing the battery pack (3) has been previously described as an example.

[0184]

[0185] Figure 12 is a drawing showing a vehicle according to one embodiment of the present invention.

[0186] Referring to FIG. 12, a battery pack (3) according to an embodiment of the present invention can be applied to a vehicle (4), such as an electric vehicle or a hybrid vehicle. That is, a vehicle (4) according to the present invention can include a battery pack (3) according to the present invention. The battery pack (3) can be installed in a body frame or a trunk space under a vehicle seat. In addition to the battery pack (3), the vehicle (4) according to the present invention can further include various other components included in the vehicle (4). For example, a vehicle (4) according to an embodiment of the present invention can further include a body, a motor, a control device such as an ECU (electronic control unit), etc., in addition to the battery pack (3) according to the present invention.

[0187] In addition, it goes without saying that the battery pack (3) according to the present invention may be equipped in other devices, apparatuses, and facilities, such as energy storage systems that use secondary batteries, in addition to automobiles (4).

[0188]

[0189] Meanwhile, although terms indicating directions such as up and down are used in this specification, it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0190] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and those skilled in the art to which the present invention pertains may make various modifications and variations within the scope of the technical spirit of the present invention and the equivalent scope of the claims to be described below. Therefore, the embodiments disclosed above should be considered in an illustrative rather than a restrictive sense. In other words, the true scope of the technical spirit of the present invention is set forth in the claims, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

[0191] [Explanation of symbols]

[0192] 1: Battery cell

[0193] 2: Pack Case

[0194] 3: Battery pack

[0195] 4: Car

[0196] 10: Electrode assembly

[0197] 11: Electrode

[0198] 11a: First electrode

[0199] 11b: Second electrode

[0200] 12: Membrane

[0201] 13: Mujibu

[0202] 13a: 1st Branch

[0203] 13b: 2nd Military Branch

[0204] 20: Cell housing

[0205] 21: Opening

[0206] 22: Closed section

[0207] 30: Whole house

[0208] 30a: First house

[0209] 30b: Second House

[0210] 31: First joint

[0211] 32: Second joint

[0212] 33: Extension

[0213] 34: Legs

[0214] 35: perimeter

[0215] 36: 1st Slope Division

[0216] 37: 2nd Slope Division

[0217] 40: Can lead

[0218] 41: Edge

[0219] 42: First Encounter

[0220] 43: Second Encounter

[0221] 44: Vent

[0222] 45: Vent notch

[0223] 46: Injection hole

[0224] 47: Plug

[0225] 50: Terminal

[0226] C: Winding center hole

[0227] A: Central axis

[0228] H: Hall

[0229] W1: First weld

[0230] W2: Second weld

[0231] W3: Third weld

Claims

1. An electrode assembly provided by being wound around the central axis of a winding center hole with a separator interposed between the first electrode and the second electrode; A cell housing in which the electrode assembly is accommodated inside and an opening is formed on one side; a can lid covering the above opening; and A current collector having a first coupling portion coupled to the electrode assembly and a second coupling portion coupled to the can lead, The above second connecting part is, A battery cell characterized in that it is spaced apart from the electrode assembly.

2. In paragraph 1, The above second connecting part is, A battery cell characterized in that it is welded to the can lead.

3. In paragraph 1, The above second connecting part is, A battery cell characterized in that it is configured to apply elastic restoring force to the can lead when pressurized by the can lead.

4. In paragraph 1, The above can lead, A battery cell characterized in that it is configured in a form that can be inserted into the inside of the cell housing through the opening.

5. In paragraph 1, The above can lead, A battery cell characterized in that it is force-fitted into the above cell housing.

6. In paragraph 1, The above second connecting part is, A battery cell characterized in that a portion of the above-mentioned entire body is manufactured by bending.

7. In paragraph 1, The above-mentioned entire house, A bridge portion connecting the first connecting portion and the second connecting portion; and A battery cell characterized in that it further includes a first inclined portion formed to be inclined while connecting the second connecting portion and the bridge portion.

8. In paragraph 7, A battery cell characterized in that the angle between the first slope and the leg is formed as an obtuse angle.

9. In paragraph 1, The above-mentioned entire house, A battery cell characterized in that it further comprises a peripheral portion formed to surround at least a portion of the first connecting portion at an edge.

10. In paragraph 9, The above-mentioned entire house, A battery cell characterized in that it further comprises a second inclined portion formed to be inclined while connecting the second connecting portion and the peripheral portion.

11. In paragraph 10, The above second slope and the above circumference, A battery cell characterized in that it is configured to be continuous overall along the circumferential direction.

12. In paragraph 10, A battery cell characterized in that the included angle between the second inclined portion and the circumferential portion is formed as an obtuse angle.

13. In paragraph 1, The above-mentioned entire house, A battery cell characterized in that it is configured so as not to come into contact with the cell housing.

14. In paragraph 1, The above-mentioned entire house, A battery cell characterized by having a plurality of the second connecting portions.

15. In paragraph 14, The above-mentioned entire house, A battery cell characterized by having three of the above second connecting portions.

16. In paragraph 1, The above can lead, A battery cell characterized in that it is welded to the cell housing.

17. A battery pack comprising at least one battery cell according to any one of claims 1 to 16.

18. A vehicle characterized by including at least one battery pack according to paragraph 17.

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