Battery cell, battery pack comprising battery cell, and vehicle

Abstract

A battery cell according to the present application includes: an electrode assembly in which a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode are wound around a winding axis; a battery case having an open end portion to allow the electrode assembly to be inserted into the battery case; and a cover assembly including a case cover configured to seal the open end portion and a first current collecting plate detachably assembled to the case cover, wherein the first current collecting plate is seated in the open end portion to be electrically connected to the first electrode.

Description

Technical Field

[0001] This disclosure relates to a battery cell, a battery pack including the battery cell, and a vehicle, and more specifically, to a battery cell having an improved assembly structure between a battery housing, a current collector, and a housing cover.

[0002] This application is based on and claims priority to Korean Patent Application No. 10-2024-0193088, filed with the Korean Intellectual Property Office on December 20, 2024, the entire disclosure of which is incorporated herein by reference. Background Technology

[0003] Secondary batteries, which are highly adaptable based on product grouping and electrical characteristics such as high energy density, are typically used not only in portable devices but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric power sources.

[0004] These secondary batteries are attracting attention as a new energy source that improves eco-friendliness and energy efficiency because they not only have the major advantage of significantly reducing the use of fossil fuels, but also do not have the byproducts generated by the use of energy.

[0005] Cylindrical, prismatic, and pouch-type battery cells are widely known types of secondary batteries. In the case of cylindrical battery cells, insulating separators are inserted between the positive and negative electrodes, and these separators are wound to form a wound-core electrode assembly, which is then inserted into a casing along with the electrolyte to constitute the battery. Strip-shaped electrode tabs can be connected to the uncoated portions of each of the positive and negative electrodes, and these tabs electrically connect the electrode assembly to the exposed electrode terminals. For reference, the positive terminal is the cap of a seal that seals the opening of the casing, while the negative terminal is the casing itself.

[0006] However, according to conventional cylindrical batteries with this structure, there are problems of high resistance, significant heat generation and poor current collection efficiency due to the current concentration in the strip electrode tabs connected to the uncoated positive and / or uncoated negative portions.

[0007] For small cylindrical batteries with a form factor of 1865 or 2170, resistance and heat generation are not significant issues. However, when increasing the form factor of cylindrical batteries for use in electric vehicles, there is a risk of fire due to the large amount of heat generated around the electrode tabs during fast charging.

[0008] To address this issue, a cylindrical battery with the following structure (the so-called tabless cylindrical battery) has been proposed, wherein the uncoated positive electrode portion and the uncoated negative electrode portion are designed to be located at the upper and lower ends of the wound electrode assembly, respectively, and the current collector is welded to these uncoated portions to improve current collection efficiency.

[0009] Meanwhile, as disclosed in Korean Patent Publication No. 10-2024-0069584, conventional cylindrical battery cells include a beading portion and a crimping portion for assembling a current collector, battery casing, and casing cover. The beading portion has an inwardly press-fit shape in the area between an opening formed on one side of the battery casing and a receiving portion accommodating the electrode assembly. Furthermore, the crimping portion has a shape extending from the beading portion and bending to surround the outer periphery of the casing cover. Cylindrical batteries with beading and crimping portions have the advantages of facilitating the fixing of the negative electrode current collector and providing excellent airtightness between the battery casing and casing cover. However, the processes for forming the beading and crimping portions are precision-requiring and not simple processes. Therefore, product defects may frequently occur during the beading or crimping fixing processes, leading to reduced production yield. Furthermore, cylindrical batteries with beading and crimping portions are disadvantageous in terms of energy density. Therefore, it is necessary to eliminate the grooved and rolled edges from the battery casing and to improve the sealing structure more easily. Summary of the Invention

[0010] Technical issues

[0011] This disclosure is designed to solve problems in the related art, and therefore aims to provide a battery cell that eliminates grooves and rolled edges, seals the battery casing with a casing cover, and electrically connects to a current collector, unlike conventional battery cells.

[0012] This disclosure relates to providing a battery cell that can facilitate the alignment of the housing cover and current collector relative to the battery housing during manufacturing, thereby improving the welding quality between the battery housing, housing cover, current collector and electrode assembly.

[0013] The technical problems to be solved by this disclosure are not limited to those described above, and other problems not mentioned herein will be clearly understood by those skilled in the art based on the following description of this disclosure.

[0014] Technical solution

[0015] According to this disclosure, a battery cell may be provided, the battery cell including an electrode assembly in which a first electrode, a second electrode, and a separator inserted between the first electrode and the second electrode are wound around a winding shaft; a battery housing having an open end to allow the electrode assembly to be inserted into the battery housing; and a cover assembly including a housing cover configured to seal the open end and a first current collector detachably assembled to the housing cover, and the cover assembly being disposed on the open end such that the first current collector is electrically connected to the first electrode.

[0016] The cover assembly can be configured such that the first current collector surrounds the outer periphery of the housing cover, and the housing cover is pressed into the inner region of the first current collector.

[0017] The cover assembly can be configured such that the housing cover and the first current collector contact each other to fit together.

[0018] The first current collector may have a welding tip that contacts the inner surface of the opening end and the outer surface of the housing cover, and the end of the welding tip protrudes outside the opening end and is exposed to the outside of the battery housing, and the welding tip may be heat-fused to integrally join the opening end, the first current collector and the housing cover.

[0019] The first current collector can be configured such that the welding tip surrounds the outer periphery of the housing cover, and the housing cover can be configured to be disposed in the inner region of the first current collector surrounded by the welding tip.

[0020] The welding tip can be configured to resiliently press against the outer periphery of the housing cover.

[0021] The first current collector may include: a central portion extending radially; a peripheral portion axially offset relative to the central portion and located radially outside the central portion; and an inclined connecting portion connecting the central portion and the peripheral portion, wherein the welding tip may be bent at the end of the peripheral portion and extend axially.

[0022] The housing cover may include: an inner cover portion extending radially; an outer cover portion axially offset relative to the inner cover portion and located radially outside the inner cover portion; and a connecting cover portion connecting the inner cover portion and the outer cover portion, wherein the central portion of the first current collector and the inner cover portion may be configured to face and contact each other axially.

[0023] The central portion of the first current collector and the electrode assembly can be configured to face each other axially and in contact.

[0024] The electrode assembly may include a first uncoated portion extending from the first electrode, and the housing cover, the first current collector, and the first uncoated portion may be configured to be triple-welded together.

[0025] The peripheral portion of the first current collector and the outer cover portion of the housing cover can face and contact each other axially, and are axially spaced apart from the electrode assembly.

[0026] The peripheral portion of the first current collector may have a protrusion formed to project axially, and the outer cover portion of the housing cover may have a groove portion that engages with the protrusion portion.

[0027] The housing cover may have an electrolyte injection hole at its center, and the first current collector may have a central hole facing the electrolyte injection hole at its center, and the central hole may be arranged axially facing the hollow portion arranged at the center of the core of the electrode assembly.

[0028] The battery casing may have a closed portion on the axially opposite side of the open end, and the closed portion may be provided with a cell terminal electrically connected to the second electrode of the electrode assembly.

[0029] According to another aspect of this disclosure, a battery pack including the aforementioned battery cells can be provided.

[0030] According to another aspect of this disclosure, a vehicle including the aforementioned battery pack can be provided.

[0031] Beneficial effects

[0032] According to one aspect of this disclosure, a battery cell can be provided that eliminates the grooved and rolled edges, seals the battery casing with a casing cover, and electrically connects to a current collector, unlike conventional battery cells.

[0033] In particular, according to one aspect of this disclosure, by applying a cover assembly in which the housing cover and current collector are pre-assembled, alignment between the electrodes of the battery housing, housing cover, current collector and electrode assembly can be facilitated, and thus the welding quality between components can be improved.

[0034] The effects obtained through this disclosure are not limited to those described above, and other technical effects not mentioned herein will be clearly understood by those skilled in the art from the following description of this disclosure. Attached Figure Description

[0035] Figure 1This is a schematic perspective view of a battery cell according to an embodiment of the present disclosure.

[0036] Figure 2 yes Figure 1 A schematic cross-sectional view of a battery cell.

[0037] Figure 3 This is a cross-sectional view illustrating the process of accommodating an electrode assembly into a battery housing according to an embodiment of the present disclosure.

[0038] Figure 4 It shows that it was inserted into Figure 3 A view of the electrode assembly in the battery casing and the second current collector connected to the electrode assembly.

[0039] Figure 5 It shows the inverted Figure 4 A view of the electrode assembly.

[0040] Figure 6 This is a cross-sectional view illustrating the process of placing a cover assembly onto a battery casing into which electrode assemblies are inserted, according to an embodiment of the present disclosure.

[0041] Figure 7 This is a perspective view of the cover assembly according to an embodiment of the present disclosure.

[0042] Figure 8 yes Figure 7 An exploded perspective view of the cover component.

[0043] Figure 9 It is along Figure 7 The cross-sectional view of the cover assembly is taken by line A-A'.

[0044] Figure 10 yes Figure 2 A partial enlarged view shows the welded structure between the battery casing, the first current collector, and the casing cover.

[0045] Figure 11 Is with Figure 10 The corresponding view shows the assembly structure of a battery cell according to another embodiment of the present disclosure.

[0046] Figure 12 This is a cross-sectional view showing a portion of the housing cover and a portion of the first current collector according to another embodiment of the present disclosure.

[0047] Figure 13 yes Figure 12 A combined view of the housing cover and the first collector plate.

[0048] Figure 14 This is a view used to describe a battery pack including battery cells according to embodiments of the present disclosure.

[0049] Figure 15 It is used to describe including Figure 14 A view of the vehicle with its battery pack. Detailed Implementation

[0050] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Before description, it should be understood that the terminology used in the specification and appended claims should not be construed as limited to its general or dictionary meaning, but rather is based on the principle of allowing the inventor to appropriately define terms for the best interpretation, and is interpreted based on the meaning and concept corresponding to the technical aspects of the present disclosure. Therefore, the embodiments described in this specification and the configurations shown in the accompanying drawings are merely some of the most preferred embodiments of the present disclosure and are not intended to fully represent all technical aspects of the present disclosure. Thus, it should be understood that various equivalents and modifications can be made to them upon filing this application.

[0051] Additionally, to aid in understanding this disclosure, the accompanying drawings are not shown to scale, but the dimensions of some components may be exaggerated. Furthermore, in different embodiments, the same reference numerals may be assigned to the same components.

[0052] Figure 1 This is a schematic perspective view of a battery cell according to an embodiment of the present disclosure, and Figure 2 yes Figure 1 A schematic cross-sectional view of a battery cell.

[0053] Reference Figure 1 and Figure 2 According to an embodiment of the present disclosure, the battery cell 10 includes an electrode assembly 100, a battery casing 200, a cover assembly 300, and cell terminals 400.

[0054] The electrode assembly 100 includes a first uncoated portion 110 and a second uncoated portion 120. Specifically, the electrode assembly 100 has a structure in which a first electrode, a second electrode, and a separator interposed between the first and second electrodes are wound around a winding shaft to define a core and an outer peripheral surface. That is, the electrode assembly 100 applied in this disclosure can be a wound-core type electrode assembly 100. In this case, an additional separator for insulation from the battery housing 200 can be disposed on the outer peripheral surface of the electrode assembly 100. The electrode assembly 100 can have a winding structure known in the art, but is not limited thereto.

[0055] The first electrode includes a first electrode current collector and a first electrode active material coated on one or both surfaces of the first electrode current collector. In the width direction of the first electrode (with... Figure 2The battery cell 10 shown has an uncoated portion at one end (in the Z direction, parallel to the height direction) where the first electrode active material is not coated. That is, the first electrode includes an uncoated portion where the active material is not coated at the long side end along the winding direction and is exposed to the outside of the separator. The uncoated portion of the electrode tab used as the first electrode is hereinafter referred to as the first uncoated portion 110. The first uncoated portion 110 is located in the Z direction (parallel to the height direction) where the active material is not coated at one end. Figure 2 The battery cell 10 shown is positioned above the electrode assembly 100 housed within the battery casing 200 on a Z-direction (parallel to its height). Specifically, the first electrode includes a first uncoated portion 110, which has no active material layer coated on its long side end along the winding direction and is exposed to the outside of the separator. At least a portion of the first uncoated portion 110 itself serves as an electrode tab. The first uncoated portion 110 may be, for example, a negative electrode tab.

[0056] Meanwhile, at least a portion of the first uncoated portion 110 may include a plurality of segments separated along the winding direction of the electrode assembly 100. In this case, the plurality of segments may be bent along the radial direction of the electrode assembly 100. The plurality of bent segments may overlap in multiple layers. The first current collector 320 may be disposed on top of the first uncoated portion 110. For example, the first uncoated portion 110 and the first current collector 320 may be in contact with each other, and at least a portion of the contact area may be soldered.

[0057] The second electrode includes a second electrode current collector and a second electrode active material coated on one or both surfaces of the second electrode current collector. In the width direction (parallel to the Z-axis), there is an uncoated portion at the other end of the second electrode current collector, where the second electrode active material is not coated. This uncoated portion of the electrode tab used as the second electrode is referred to herein as the second uncoated portion 120. Figure 2 In this configuration, the second uncoated portion 120 is located below the electrode assembly 100 housed within the battery casing 200. Specifically, the second electrode current collector includes the second uncoated portion 120, which has no active material layer coated on its long side and is exposed to the outside of the separator; at least a portion of the second uncoated portion 120 itself serves as an electrode tab. The second uncoated portion 120 can be, for example, a positive electrode tab.

[0058] Meanwhile, at least a portion of the second uncoated portion 120 may include multiple segments separated along the winding direction of the electrode assembly 100. In this case, the multiple segments may be bent along the radial direction of the electrode assembly 100. The multiple bent segments may overlap in multiple layers. The second current collector 340 may be disposed below the second uncoated portion 120. For example, the second uncoated portion 120 and the second current collector 340 may be connected by welding.

[0059] The first uncoated portion 110 and the second uncoated portion 120 extend in opposite directions along the height direction of the battery (parallel to the Z-axis). The first uncoated portion 110 extends toward the opening end 210 of the battery housing 200, and the second uncoated portion 120 extends toward the closing portion 220 located on the opposite side of the opening end 210.

[0060] See Figures 1 to 3 The battery housing 200 can be configured to house the electrode assembly 100. The battery housing 200 is a generally cylindrical receiver with an open end 210 formed on one side, and is made of a conductive material such as metal. Examples of materials used for the battery housing 200 may include steel, stainless steel, nickel-plated iron, etc.

[0061] Specifically, the battery housing 200 may include a sidewall portion, a closed portion 220 connected to one axial (Z-direction) end of the sidewall portion, and an open end portion 210 disposed at the other axial end of the sidewall portion. The sidewall portion and the closed portion 220 of the battery housing 200 may be integrally formed. The closed portion 220 has a generally flat shape. The sidewall portion may be cylindrical, connected to the closed portion 220, and extend in the axial direction. The side of the sidewall portion not connected to the closed portion 220 may be defined as the open end portion 210 of the battery housing 200. Figure 3 As shown, the electrode assembly 100 can be accommodated in the internal space of the battery housing 200 through the open end 210. At this time, the electrode assembly 100 can be accommodated in the battery housing 200 such that the first uncoated portion 110 faces the open end 210 and the second uncoated portion 120 faces the closed portion.

[0062] The battery housing 200 is electrically connected to the first electrode of the electrode assembly 100. For example, the battery housing 200 is electrically connected to the first uncoated portion 110 of the electrode assembly 100. The battery housing 200 may be configured to directly contact the first current collector 320 of the first uncoated portion 110. In this case, the battery housing 200 has the same polarity as the first uncoated portion 110.

[0063] The cell terminal 400 is made of a conductive metal material. For example, aluminum (Al) can be used as the material for the cell terminal 400. Figure 2 In this configuration, the cell terminal 400 is disposed in the closed portion 220 located on the opposite side of the open end 210 of the battery housing 200. The cell terminal 400 is configured to be electrically connected to the second uncoated portion 120 of the electrode assembly 100. For example, as... Figure 2As shown, the second uncoated portion 120 can be connected to the second current collector 340, and the cell terminal can pass through the closure portion 220 in the axial direction to connect to the second current collector 340. In this case, the cell terminal 400 has the same polarity as the second electrode. Therefore, the cell terminal 400 is electrically connected to the second electrode of the electrode assembly 100 and has the same second polarity as the second electrode. The cell terminal 400 is configured to be electrically insulated from the battery housing 200, which is electrically connected to the first electrode and has a first polarity.

[0064] Electrical insulation between the cell terminal 400 and the battery casing 200 can be achieved in various ways. For example, insulation can be achieved by inserting an insulator 224 between the second current collector 340 and the closing portion 220 of the battery casing 200, and by inserting an insulating washer 223 between the cell terminal 400 and the battery casing 200. Alternatively, insulation can be achieved by forming an insulating coating on a portion of the cell terminal 400. Alternatively, methods for structurally securing the cell terminal 400 can be applied so that contact between the cell terminal 400 and the battery casing 200 is impossible. Alternatively, a combination of the above methods can be used.

[0065] At the same time, such as Figure 4 and Figure 5 As shown, for example, in this embodiment, the electrode assembly 100 is inserted into the battery housing 200 through the open end 210, while the second current collector 340 is pre-soldered to the second uncoated portion 120, and the first current collector 320 is not soldered to the first uncoated portion 110. Furthermore, the open end 210 of the battery housing 200 can be sealed using the cover assembly 300, which will be described later.

[0066] Specifically, such as Figure 6 As shown, in the battery cell 10 according to this embodiment, during the assembly process, the electrode assembly 100 is inserted into the battery housing 200 such that the second uncoated portion 120 having the second current collector 340 faces the closed portion, and the first uncoated portion 110 faces the open end 210, and then the cover assembly 300 is assembled into the open end 210. Here, the cover assembly 300 includes the housing cover 310 and the first current collector 320, and refers to the assembly in which the housing cover 310 and the first current collector 320 are pre-assembled and integrated.

[0067] In the case of a conventional battery cell 10, for example, the current collector is welded to the first uncoated portion 110 of the electrode assembly 100 inserted into the battery housing 200, and then the housing cover 310 is assembled into the open end 210. Furthermore, two steps are performed: welding the battery housing 200 and the current collector, and welding the battery housing 200 and the housing cover 310; or a single step of welding the battery housing 200, the current collector, and the housing cover 310 is performed. However, regardless of the welding method used, conventional battery cells 10 may have problems with reduced welding quality, such as poor sealing due to welding defects, if the components are not aligned.

[0068] However, by applying the cover assembly 300 according to this disclosure, alignment between components can be performed more easily and precisely. For example, since the cover assembly 300 according to this disclosure is an assembly in which the housing cover 310 and the first current collector 320 are pre-assembled, the cover assembly 300 can be aligned and assembled into the opening end 210 of the battery housing 200. When assembling the housing cover into the battery housing, conventional battery cells may not be able to smoothly perform the subsequent welding process unless there is precise alignment not only between the housing cover and the battery housing but also between the housing cover and the current collector. However, according to this disclosure, as Figure 6 As shown, the cover assembly 300, assembled with the housing cover 310 and the first current collector 320 pre-aligned, is placed on the opening end 210 of the battery housing 200. In this case, compared with the prior art, the alignment and welding between components can be performed more easily and accurately during the process of assembling the housing cover 310 and the first current collector 320 into the battery housing 200.

[0069] Figure 7 This is a perspective view of a cover assembly according to an embodiment of the present disclosure. Figure 8 yes Figure 7 Exploded perspective view of the cover component. Figure 9 It is along Figure 7 The cross-sectional view of the cover assembly taken by line A-A', and Figure 10 yes Figure 2 A partially enlarged view shows the welded structure between the battery casing, the first current collector, and the casing cover.

[0070] Referring to the accompanying drawings, the cover assembly 300 according to this disclosure includes a housing cover 310 and a first current collector 320.

[0071] like Figure 7 and Figure 8As shown, the cover assembly 300 can be configured such that the first current collector 320 surrounds the outer periphery of the housing cover 310, and the housing cover 310 is press-fitted into the inner region of the first current collector 320. Additionally, the cover assembly 300 can be configured such that the housing cover 310 and the first current collector 320 contact each other for a fitted fit.

[0072] The cover assembly 300 is an assembly in which the housing cover 310 and the first current collector 320 are pre-assembled, and can be configured to be integrally mounted on the battery housing 200. When this cover assembly 300 is used, assembly tolerances caused by misalignment, such as the housing cover 310 tilting up and down or rotating left and right relative to the first current collector 320, can be significantly reduced compared to when the first current collector 320 and the housing cover 310 are inserted into the battery housing 200 separately.

[0073] More specifically, such as Figure 8 and Figure 9 As shown, the first current collector 320 may include: a central portion 321 having a core hollow portion capable of communicating with the electrode assembly 100 and extending radially based on a central hole 325; a peripheral portion 322 offset relative to the central portion 321 in the axial direction (Z direction) and located radially outside the central portion 321; an inclined connecting portion 323 connecting the central portion 321 and the peripheral portion 322; and a welding tip portion 324 bent at the end of the peripheral portion 322 and extending axially.

[0074] Furthermore, the housing cover 310 may include a radially extending inner cover portion 311, an outer cover portion 312 that is offset from the inner cover portion 311 in the axial direction (Z direction) and located radially outside the inner cover portion 311, and a connecting cover portion 313 that connects the inner cover portion 311 and the outer cover portion 312.

[0075] like Figure 9 As shown, when the housing cover 310 is pressed into the first current collector plate 320, the central portion 321 and the inner cover portion 311 of the first current collector plate 320 can be configured to face each other axially and contact each other. Furthermore, the peripheral portion 322 of the first current collector plate 320 and the outer cover portion 312 of the housing cover 310 can be configured to face each other axially and contact each other.

[0076] Furthermore, the welding tip 324 of the first current collector 320 can be provided in an annular shape on the outermost portion of the first current collector 320 and configured to surround the outer periphery of the housing cover 310. The welding tip 324 can be configured to elastically press the outer periphery of the housing cover 310 when the housing cover 310 is located in the inner region of the first current collector 320 surrounded by the welding tip 324. Therefore, the housing cover 310 and the first current collector 320 can be fixed in close contact with each other. When the cover assembly 300 is inserted into the battery housing 200, the housing cover 310 will not tilt or rotate vertically relative to the first current collector 320. Therefore, when the cover assembly 300 is inserted into the battery housing 200, it is not necessary to specifically check for alignment errors between the housing cover 310 and the first current collector 320.

[0077] Meanwhile, the housing cover 310 according to this embodiment may have a venting cutout 317, which is configured to open when the pressure inside the battery housing 200 exceeds a threshold. For example, the venting cutout 317 may be formed on both surfaces of the housing cover 310, and may be formed on the surfaces of the housing cover 310 according to at least one pattern selected from continuous circular patterns, discontinuous circular patterns, and linear patterns. In addition, the venting cutout 317 may be formed in various other patterns.

[0078] Next, the welding structure of the battery cell 10 according to this embodiment will be described.

[0079] Reference Figure 2 and Figure 10 When the cover assembly 300 is inserted into the battery housing 200, the central portion 321 of the first current collector 320 axially faces and contacts the electrode assembly 100, and the peripheral portion 322 of the first current collector 320 can be arranged to be axially spaced 'D2' from the electrode assembly 100.

[0080] The first current collector 320 of the cover assembly 300 can be arranged to contact the first uncoated portion 110 extending from the first electrode of the electrode assembly 100. Therefore, the first current collector 320 can be electrically connected to the first electrode.

[0081] Furthermore, the housing cover 310, the first current collector 320, and the first uncoated portion 110 can be triple-welded. That is, the inner cover portion of the housing cover 310, the central portion 321 of the first current collector 320, and the first uncoated portion 110 of the first electrode can be integrally welded. As described above, the inner cover portion 311 and the central portion 321 are in close contact with each other, and the central portion 321 and the first uncoated portion 110 are arranged to be in contact with each other, such that the inner cover portion 311, the central portion 321, and the first uncoated portion 110 can be welded, for example, by irradiating a laser from the outside of the battery cell 10. Figure 10 As shown in "W2".

[0082] Furthermore, in the case of the battery cell 10 according to this embodiment, the housing cover 310 and the first current collector are in close contact with each other, and therefore, when heat is generated in the electrode assembly 100, the heat can be conducted to the housing cover 310 more quickly. Therefore, if a cooling device (not shown) is arranged on the side of the housing cover 310, the heat of the electrode assembly can be dissipated more effectively.

[0083] In addition, the battery casing 200, casing cover 310 and first current collector 320 can be triple-welded.

[0084] like Figure 10 As shown, when the cover assembly 300 is inserted into the battery housing 200, the cover assembly 300 can be arranged such that the welding tip 324 of the first current collector 320 contacts the inner surface 211 of the opening end 210 and the outer surface 312a of the housing cover 310, and the end protrudes outside the opening end 210 to be exposed to the outside, as shown in 'D1'.

[0085] The triple welding between the battery casing 200, the casing cover 310, and the first current collector 320 can be performed by using a thermoforming welding tip 324 to integrally join the opening end 210 of the battery casing 200, the first current collector 320, and the casing cover 310. For example, this can be achieved by irradiating the welding tip 324 with a laser from the outside of the battery cell 10. Figure 10 As shown by 'W1', the welding tip 324 can be melted and bonded to the opening end 210 and the housing cover 310. When the welding tip 324 melts, it can be inserted into the gap that may appear when the cover assembly 300 is placed on the opening end 210 of the battery housing 200, thereby improving airtightness due to the gap-filling effect. Furthermore, since welding is performed by melting only the first current collector plate 320, it has the advantage of being able to weld at low output. Specifically, according to this embodiment, the peripheral portion 322 of the first current collector plate 320 is spaced 'D2' from the first uncoated portion 110, and furthermore, the welding tip 324 can weld at low output, thereby significantly reducing the risk of damage to the first uncoated portion 110 due to welding heat.

[0086] Meanwhile, the housing cover 310 may have an electrolyte injection hole 314 at the center of the inner cover portion 311. The electrolyte injection hole 314 may be formed to penetrate the inner cover portion 311 of the housing cover 310 and face the hollow portion formed at the center of the core of the electrode assembly 100. A central hole 325 facing the electrolyte injection hole 314 may be provided at the center of the first current collector plate 320. The central hole 325 may be formed to penetrate the central portion 321 of the first current collector plate 320.

[0087] For example, as described above, after welding the battery casing 200, casing cover 310, and first current collector 320, and after welding the casing cover 310, first current collector 320, and first uncoated portion 110, electrolyte can be injected into the battery casing 200 through the electrolyte injection hole 314 and the center hole 325. After electrolyte injection is completed, the electrolyte injection hole 314 can be closed. For example, the electrolyte injection hole 314 can be covered by a cap 330 provided in the form of a metal disc, and the periphery of the cap 330 can be welded to ensure airtightness.

[0088] Although not shown, unlike this embodiment, the electrolyte injection hole 314 can be sealed by pressing a ball into it. In this case, welding can be performed at the contact interface between the ball and the electrolyte injection hole 314, or an adhesive can be applied to the contact interface between the ball and the electrolyte injection hole 314. Also, unlike this embodiment, electrolyte injection is performed by forming a terminal hole in the cell terminal 400 provided in the closed portion of the battery housing 200, injecting electrolyte, and then sealing the terminal hole. In this case, the electrolyte injection hole 314 does not need to be formed in the housing cover 310.

[0089] Next, another embodiment of the battery cell 10 according to this disclosure will be described.

[0090] Figure 11 Is with Figure 10 The corresponding view shows the assembly structure of the battery cell 10 according to another embodiment of the present disclosure. Figure 12 This is a cross-sectional view showing a portion of the housing cover 310 and a portion of the first current collector 320 according to another embodiment of the present disclosure, and Figure 13 yes Figure 12 A combined view of the housing cover 310 and the first collector plate 320.

[0091] The same reference numerals as in the preceding figures denote the same parts, and repeated descriptions of the same parts will be omitted; the main focus will be on the differences from the embodiments described above.

[0092] The battery cell 10 according to another embodiment of this disclosure differs from the battery cell of the above embodiment in that the assembly structure of the cover assembly 300 is the same, while the rest of the construction is the same.

[0093] like Figure 12 As shown, according to another embodiment of the present disclosure, the cover assembly 300 includes a protrusion 327 formed to axially protrude from the periphery 322 of the first current collector 320, and a recess 318 configured to engage with the protrusion 327 in the outer cover portion 312 of the housing cover 310.

[0094] The protrusion 327 and the recess 318 can be used as assembly guides to guide the assembly position, so that the housing cover 310 and the first current collector 320 can be assembled in a manner that precisely aligns them with each other. In addition, after the housing cover 310 and the first current collector 320 are assembled, the protrusion 327 and the recess 318 can be used as stops to inhibit relative movement.

[0095] For example, such as Figure 12 As shown, the housing cover 310 can be mounted on the first current collector plate 320, such that the recessed portion 318 of the housing cover 310 is fitted into the protrusion 327 of the first current collector plate 320, while the welding tip 324 of the first current collector plate 320 unfolds. After the housing cover 310 is mounted on the first current collector plate 320, the welding tip 324 can return to its original state to elastically press the outer periphery of the housing cover 310. Then, the housing cover 310 and the first current collector plate 320 can be stably fixed to each other. As described above, after the cover assembly 300 is assembled to the opening end 210 of the battery housing 200 such that the welding tip 324 protrudes outward to the outside of the opening end 210 of the battery housing 200, the welding tip 324 can be melted to simultaneously bond the battery housing 200, the housing cover 310, and the first current collector plate 320, thereby reducing welding time while ensuring the airtightness of the battery housing 200.

[0096] As described above, the battery cell 10 can be housed in the casing 2 of the battery pack 1, such as... Figure 14 As shown. Battery pack 1 can be configured using battery modules as an intermediate form of component, or it can be configured directly as a battery pack without battery modules, as shown. In this embodiment, battery pack 1, which directly houses the battery cells 10 in the battery pack housing without configuring battery modules, can achieve a higher energy density.

[0097] A battery pack 1 with this high energy density can store the same amount of energy while reducing its size and weight. Therefore, when a battery pack 1 including such battery cells 10 is installed in a vehicle, such as an electric vehicle that uses electricity as its energy source, ... Figure 15 As shown, the vehicle's range relative to energy consumption can be further increased.

[0098] A vehicle according to an embodiment of the present disclosure includes a battery pack 1 according to an embodiment of the present disclosure. According to an embodiment of the present disclosure, the vehicle can be configured to operate by receiving power from the battery pack 1.

[0099] It should be understood that the above embodiments are exemplary and not restrictive in all respects, and the scope of this disclosure will be indicated by the claims described later rather than by the detailed description above. Furthermore, the meaning and scope of the claims described later, as well as all variations and modifications derived from equivalent concepts, should be construed as being included within the scope of this disclosure.

[0100] The present disclosure has been described above with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments and drawings disclosed in this specification. Various modifications can be made by those skilled in the art within the scope of the technical concept of the present disclosure. Furthermore, even if the effects of the configuration according to the present disclosure are not explicitly described in the foregoing description of the embodiments of the present disclosure, it should be understood that the effects predicted by the corresponding configuration are obvious.

Claims

1. A battery cell, the battery cell comprising: An electrode assembly in which a first electrode, a second electrode, and a diaphragm inserted between the first electrode and the second electrode are wound around a winding shaft; A battery housing having an open end to allow the electrode assembly to be inserted into the battery housing; as well as A cover assembly comprising a housing cover configured to seal the opening end and a first current collector detachably assembled to the housing cover, the cover assembly being disposed on the opening end such that the first current collector is electrically connected to the first electrode.

2. The battery cell according to claim 1, in, The cover assembly is configured such that the first current collector surrounds the outer periphery of the housing cover, and the housing cover is pressed into the inner region of the first current collector.

3. The battery cell according to claim 1, in, The cover assembly is configured such that the housing cover and the first current collector contact each other to fit together.

4. The battery cell according to claim 1, in, The first current collector has a welding tip that contacts the inner surface of the opening end and the outer surface of the housing cover, and the end of the welding tip protrudes beyond the opening end and is exposed to the outside of the battery housing. The welding tip is heat-melted to integrally join the opening end, the first current collector, and the housing cover.

5. The battery cell according to claim 4, in, The first current collector is configured such that the welding tip surrounds the outer periphery of the housing cover, and The housing cover is configured to be disposed in the inner region of the first current collector surrounded by the welding tip.

6. The battery cell according to claim 4, in, The welding tip is configured to resiliently press against the outer periphery of the housing cover.

7. The battery cell according to claim 4, in, The first current collector includes: a central portion extending radially; a peripheral portion axially offset relative to the central portion and located radially outward of the central portion; and an inclined connecting portion connecting the central portion and the peripheral portion. The welding tip is bent at the end of the peripheral portion and extends axially.

8. The battery cell according to claim 7, in, The housing cover includes: an inner cover portion extending radially; an outer cover portion axially offset relative to the inner cover portion and located radially outward of the inner cover portion; and a connecting cover portion connecting the inner cover portion and the outer cover portion. The central portion and the inner cover portion of the first current collector are configured to face each other axially and in contact.

9. The battery cell according to claim 8, in, The central portion of the first current collector and the electrode assembly are configured to face each other axially and in contact.

10. The battery cell according to claim 9, in, The electrode assembly includes a first uncoated portion extending from the first electrode, and The housing cover, the first current collector, and the first uncoated part are welded together in a triple manner.

11. The battery cell according to claim 8, in, The peripheral portion of the first current collector faces and contacts the outer cover portion of the housing cover axially, and is axially spaced from the electrode assembly.

12. The battery cell according to claim 8, in, The peripheral portion of the first current collector has a protrusion formed to project axially, and The outer cover portion of the housing cover has a groove portion that engages with the protrusion portion.

13. The battery cell according to claim 1, in, The housing cover has an electrolyte injection hole at its center. The first current collector has a central hole facing the electrolyte injection hole, and The central hole is arranged axially facing the hollow portion located at the center of the core of the electrode assembly.

14. The battery cell according to claim 1, in, The battery casing has a closed portion on the axially opposite side of the open end, and a cell terminal electrically connected to the second electrode of the electrode assembly is provided in the closed portion.

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

16. A vehicle comprising a battery pack according to claim 15.

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