Welding fixture, battery cell produced using the welding fixture, and battery pack and vehicle including the battery cell

Abstract

Disclosed are a welding jig, a battery cell produced using the welding jig, a battery pack including the battery cell, and a vehicle. According to one embodiment of the present invention, a welding jig is a welding jig for welding an electrode assembly and a current collector plate in a battery cell including an electrode assembly, a battery can accommodating the electrode assembly, and a current collector plate electrically connected to the electrode assembly, the current collector plate having a concave or convex pattern formed thereon, wherein the welding jig includes a mask portion having a convex or concave pattern formed corresponding to the concave or convex pattern of the current collector plate, and a welding hole for welding formed in the mask portion, and a support portion coupled to the mask portion and supporting the mask portion.

Description

Technical Field

[0001] This application claims priority to Korean Patent Application No. 10-2025-0009041, filed with the Korean Intellectual Property Office on January 21, 2025, the disclosure of which is incorporated herein by reference in its entirety.

[0002] This disclosure relates to a welding fixture and a battery cell produced using the welding fixture, as well as a battery pack and a vehicle including the battery cell, and more specifically, to a welding fixture capable of improving welding quality and a battery cell produced using the welding fixture, as well as a battery pack and a vehicle including the battery cell. Background Technology

[0003] Secondary batteries are highly adaptable across different product groups and have electrical characteristics such as high energy density, so they are often used not only in portable devices, but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric power sources.

[0004] This type of secondary battery is gaining attention as a new energy source to improve eco-friendliness and energy efficiency because it not only has the major advantage of significantly reducing the use of fossil fuels, but also produces no byproducts from energy use.

[0005] Currently widely used rechargeable batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these rechargeable battery cells is approximately 2.5V to 4.5V.

[0006] Therefore, when a higher output voltage is required, multiple battery cells can be connected in series to form a battery module or battery pack. Alternatively, depending on the required charging and discharging capacity, multiple battery cells can be connected in parallel to form a battery module or battery pack. Thus, the number of battery cells and the type of electrical connection included in a battery module or battery pack can vary depending on at least one of the required output voltage and the required charging and discharging capacity.

[0007] Meanwhile, cylindrical battery cells, prismatic battery cells, and pouch battery cells are known as types of secondary battery cells. In the case of cylindrical battery cells, a separator, which serves as an insulator, is inserted between the positive and negative electrode plates and wound up to form a wound-core electrode assembly. This wound-core electrode assembly is placed in a battery can along with the electrolyte to form a battery.

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

[0009] The current collector can be connected to the electrode assembly in various ways, and for example, various welding methods including laser welding can be used.

[0010] However, the electrode assembly is a very sensitive component, and when the current collector is attached to the electrode assembly by laser welding, spatter may occur, and damage due to heat may occur. Summary of the Invention

[0011] Technical issues

[0012] This disclosure was designed to address the problems in the related technologies, and therefore aims to provide a welding fixture that can protect the current collector and the electrode assembly when welding the current collector to the electrode assembly, a battery cell produced using the welding fixture, and a battery pack and vehicle including the battery cell.

[0013] In addition, this disclosure aims to provide a welding fixture and a battery cell produced using the welding fixture, as well as a battery pack and a vehicle including the battery cell. The welding fixture can improve the accuracy of the welding position according to the combination of recesses and protrusions when welding current collectors to electrode assemblies, thereby increasing the welding joint area.

[0014] In addition, this disclosure aims to provide a welding fixture capable of preventing spatter and damage due to heat, a battery cell produced using the welding fixture, and a battery pack and vehicle including the battery cell.

[0015] In addition, this disclosure aims to provide a welding fixture that can improve the performance of a battery cell by increasing welding strength and improving welding quality, a battery cell produced using the welding fixture, and a battery pack and vehicle including the battery cell.

[0016] However, the technical problems to be solved by this disclosure are not limited to those described above, and those skilled in the art can clearly understand other problems not mentioned herein through the following description of this disclosure.

[0017] Technical solution

[0018] According to one aspect of this disclosure, a welding fixture for welding an electrode assembly and a current collector in a battery cell can be provided, the battery cell including the electrode assembly, a battery can housing the electrode assembly, and the current collector electrically connected to the electrode assembly, wherein the welding fixture includes: a mask unit having a recess or a protrusion formed on the current collector, a protrusion or recess formed on the mask unit corresponding to the recess or protrusion of the current collector, and a welding hole for welding formed in the mask unit; and a support unit, the mask unit being coupled to and supported by the support unit.

[0019] In one embodiment, an opening may be formed in the battery canister, the current collector may have the function of closing the opening, and the protrusion or recess of the mask unit may be tightly connected to the recess or protrusion of the current collector.

[0020] In one embodiment, the welding hole may be formed in the mask unit corresponding to at least one of a plurality of recesses or protrusions formed on the manifold.

[0021] In one implementation, the current collector can be a negative current collector.

[0022] In one embodiment, the mask unit may have an insertion groove formed to allow insertion at each of the two ends of the manifold.

[0023] In one embodiment, the end of the current collector and the battery canister can be inserted together into the insertion groove.

[0024] In one embodiment, each of the two ends of the current collector can be bent upward and connected to the inner surface of the battery can, and the current collector and the battery can be inserted together into the insertion groove with the current collector connected to the inner surface of the battery can.

[0025] In one embodiment, a plurality of recesses or protrusions may be formed on the manifold, at least one of the recesses or protrusions having an opposite surface that can contact the electrode assembly, and the remaining recesses or protrusions having opposite surfaces that can be spaced apart from the electrode assembly, and the welding hole may be formed in the mask unit at a position corresponding to the portion of the manifold that contacts the electrode assembly.

[0026] In one embodiment, the welding portion may be formed on the manifold at a location corresponding to the welding hole of the mask unit.

[0027] In one embodiment, a bridging portion in the form of a protrusion or a recess can be formed on the current collector plate to enhance the rigidity of the current collector plate. The bridging portion can be spaced apart from the electrode assembly, and a recess or protrusion can be formed on the mask unit to make close contact with the bridging portion.

[0028] In one embodiment, the size of the welding hole can be larger than the size of the bridging portion.

[0029] In one embodiment, fastening holes can be formed in the mask unit, and fastening members can fasten the mask unit and the support unit through the fastening holes.

[0030] Meanwhile, according to another aspect of this disclosure, a battery cell produced using the aforementioned welding fixture can be provided, a battery pack including at least one of the aforementioned battery cells can be provided, and a vehicle including at least one of the aforementioned battery cells can also be provided.

[0031] Beneficial effects

[0032] The embodiments disclosed herein have the effect of protecting the current collector and the electrode assembly when welding the current collector to the electrode assembly.

[0033] In addition, the implementation method has the effect of increasing the welding area by improving the accuracy of the welding position based on the combination of the concave and convex portions.

[0034] In addition, the implementation method has the effect of preventing splashing and damage due to heat.

[0035] In addition, the implementation method has the effect of improving the performance of the battery cell by increasing the welding strength and improving the welding quality.

[0036] However, the effects to be achieved by this disclosure are not limited to those described above, and those skilled in the art will clearly understand other technical effects not mentioned herein through the following description of this disclosure. Attached Figure Description

[0037] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, serve to provide a further understanding of the technical features of the present disclosure; therefore, the present disclosure is not to be construed as limited to the drawings.

[0038] Figure 1 This is a plan view of a welding fixture according to an embodiment of the present disclosure.

[0039] Figure 2 This is a bottom view of a welding fixture according to an embodiment of the present disclosure.

[0040] Figure 3 It is along Figure 1 A cross-sectional view taken from line A-A'.

[0041] Figure 4 This is a cross-sectional view showing the state of the welding fixture before it is connected to the battery cell according to an embodiment of the present disclosure.

[0042] Figure 5 It is achieved by connecting the welding fixture to Figure 4 A cross-sectional view of the battery cells being welded.

[0043] Figure 6 This is a cross-sectional view of a battery cell before welding using a welding fixture according to an embodiment of this disclosure.

[0044] Figure 7 This is a cross-sectional view of a battery cell after welding using a welding fixture according to an embodiment of the present disclosure.

[0045] Figure 8 This is a perspective view of a manifold to be welded using a welding fixture according to an embodiment of the present disclosure.

[0046] Figure 9 This is a schematic view illustrating the configuration of a battery pack including battery cells produced using welding fixtures according to each embodiment of this disclosure.

[0047] Figure 10 It is used to describe including Figure 9 A view of the vehicle with its battery pack. Detailed Implementation

[0048] The preferred embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. The terminology used in the specification and appended claims should not be construed as limited to its general and dictionary meaning, but rather should be interpreted according to the meaning and concept corresponding to the technical aspects of this disclosure, based on the principle of allowing the inventor to appropriately define terms for best interpretation. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely one embodiment of the most preferred embodiments of this disclosure and are not intended to fully represent the technical aspects of this disclosure. It should be understood that various equivalents and modifications can be made to these embodiments at the time of filing this application.

[0049] In the accompanying drawings, for convenience and clarity of description, the dimensions of each component or specific part constituting that component are exaggerated, omitted, or shown schematically. Therefore, the size of each component does not perfectly reflect its actual size. Such detailed descriptions, determining relevant known functions or configurations, will be omitted if they might unnecessarily obscure the essential points of this disclosure.

[0050] As used herein, the terms “connection” or “link” refer not only to the direct connection or linking of one component to another, but also to the indirect connection or linking of one component to another through a joint component.

[0051] Furthermore, the common content described in any embodiment of this disclosure can be applied to other embodiments. For example, in a second embodiment, some common content described in the first embodiment can be replaced by the description of the first embodiment, and such common content can be applied to the second embodiment. Moreover, the content described in the second embodiment that is applicable to the first embodiment can be applied to the first embodiment. And this also applies to other embodiments.

[0052] Figure 1This is a plan view of a welding fixture according to an embodiment of the present disclosure. Figure 2 This is a bottom view of a welding fixture according to an embodiment of the present disclosure. Figure 3 It is along Figure 1 A cross-sectional view taken from line A-A'. Figure 4 This is a cross-sectional view showing the state of the welding fixture according to an embodiment of the present disclosure before it is connected to the battery cell, and Figure 5 It is achieved by connecting the welding fixture to Figure 4 A cross-sectional view of the battery cells being welded together.

[0053] Reference Figures 1 to 5 According to an embodiment of the present disclosure, the welding fixture 10 is used for welding the electrode assembly 210 and the current collector in a battery cell 20. The battery cell 20 includes the electrode assembly 210, a battery can 220 for accommodating the electrode assembly 210, and a current collector electrically connected to the electrode assembly 210. The welding fixture 10 includes a mask unit 100 and a support unit 110.

[0054] Here, the current collector may include both the positive current collector 240 and the negative current collector 230 of the battery cell 20, but for ease of explanation, the following description focuses on the case where the current collector is the negative current collector 230.

[0055] The negative current collector 230 disposed in the battery cell 20 by welding with the welding fixture 10 according to the embodiments of the present disclosure can have the function of a cover. That is, the negative current collector 230 can not only have the function of a conventional current collector, but also have the function of a cover disposed in a conventional battery cell 20. A detailed description thereof will be provided later.

[0056] Reference Figures 1 to 3 A protrusion 102 or a recess is formed on the mask unit 100. Here, the protrusion 102 or recess formed on the mask unit 100 corresponds to the recess 231 or protrusion formed on the negative electrode current collector 230 of the battery cell 20.

[0057] Reference Figure 4 and Figure 5 A protrusion protruding toward the electrode assembly 210 is formed on the negative current collector 230, and a recess 231 is formed on the opposite surface of the protrusion. Furthermore, a protrusion 102 is formed on the mask unit 100 that is in close contact with the recess 231 of the negative current collector 230.

[0058] Here, a protrusion protruding toward the opposite side of the electrode assembly 210 may be formed on the negative current collector 230, but for ease of explanation, the following description focuses on the case where a protrusion protruding toward the electrode assembly 210 is formed on the negative current collector 230.

[0059] Furthermore, welding holes 101 for welding can be formed in the mask unit 100. For example... Figure 5 As shown, with the protrusion 102 of the mask unit 100 inserted into the recess 231 of the negative current collector 230 and in close contact with the recess 231, the welding portion 232 of the negative current collector 230 is welded by a laser, for example, through the welding hole 101 of the mask unit 100 (see...). Figure 5 (Arrow L in the text) Welding.

[0060] like Figure 4 As shown, a recess 231 is formed on the negative current collector 230, and a protrusion 102 is formed on the mask unit 100. Since the protrusion 102 of the mask unit 100 is inserted into and in close contact with the recess 231 of the negative current collector 230, the accuracy of the welding position can be improved, thereby increasing the welding joint area.

[0061] Therefore, splashing can be prevented, and damage caused by heat can be prevented. When the negative current collector 230 is welded to the electrode assembly 210, the negative current collector 230 and the electrode assembly 210 are protected, and in addition, the welding strength is increased and the welding quality is improved, which has the effect of improving the performance of the battery cell 20.

[0062] Reference Figure 4 and Figure 5 Multiple recesses 231 can be formed on the negative current collector 230, and welding holes 101 can be formed in the mask unit 100 corresponding to at least one of the multiple recesses 231 formed on the negative current collector 230.

[0063] refer to Figure 4 The opposite surface of at least one of the plurality of recesses 231 formed on the negative electrode current collector 230 (welding portion 232, see Figure 8 The remaining recess 231 contacts the electrode assembly 210. Furthermore, the opposite surface of the remaining recess 231 (bridging portion 233, see...) Figure 8 It is spaced apart from the electrode assembly 210.

[0064] Here, the welding hole 101 is formed in the mask unit 100 at a position corresponding to the portion of the negative current collector 230 that contacts the electrode assembly 210. Furthermore, the welding portion 232 is formed on the negative current collector 230 at a portion corresponding to the welding hole 101 in the mask unit 100.

[0065] A bridging portion 233, in the form of a protrusion or a recess, can be formed on the negative current collector 230 to enhance the rigidity of the negative current collector 230. Figure 4 and Figure 5In the present invention, the bridging portion 233 is formed in a raised form toward the electrode assembly 210, and the opposite surface of the raised portion is formed in a recessed form 231. However, the present disclosure is not limited thereto, and the bridging portion 233 may be formed in a raised form toward the opposite direction of the electrode assembly 210. A detailed description of the bridging portion 233 formed on the negative current collector 230 will be provided later.

[0066] refer to Figure 4 and Figure 5 The bridging portion 233 is spaced apart from the electrode assembly 210. Furthermore, a protrusion 102 that closely contacts the bridging portion 233 can be formed on the mask unit 100. Here, a protrusion 102 that closely contacts the recess of the bridging portion 233 can be formed on the mask unit 100.

[0067] In a modified embodiment, if the bridging portion 233 is formed in a protruding form in the opposite direction to the electrode assembly 210, a recess is formed on the mask unit 100, and the recess of the mask unit 100 can be configured to be in close contact with the protrusion of the bridging portion 233.

[0068] refer to Figure 4 and Figure 5 The bridging portion 233 can be formed to be smaller than the welding hole 101. That is, the size of the welding hole 101 can be formed to be larger than the size of the bridging portion 233. Since the size of the welding hole 101 is increased in this way, the size of the welding portion 232 is also increased, thereby enabling large-area welding.

[0069] Reference Figure 4 and Figure 5 The mask unit 100 may have an insertion groove 103 formed to allow insertion of each of the two ends of the negative current collector 230. As described later, the negative current collector 230 may be directly coupled to the battery canister 220. In this case, each of the two ends of the negative current collector 230 may be bent upward and coupled to the inner surface of the battery canister 220 (see [link to documentation]). Figure 4 Part B).

[0070] And, as Figure 5 As shown, with the negative current collector 230 connected to the inner surface of the battery canister 220, the end of the negative current collector 230 and the battery canister 220 can be configured to be inserted together into the insertion recess 103 (see [reference]). Figure 5 Part C).

[0071] In this way, when the end of the negative current collector 230 is inserted into the insertion groove 103 together with the battery can 220, the mask unit 100 supports the battery can 220 and the negative current collector 230 together, thereby improving the accuracy of the welding position.

[0072] refer to Figure 3 The mask unit 100 is configured to be connected to and supported by the support unit 110. The mask unit 100 can be supported in various ways, for example, a fastening hole 104 can be formed on the mask unit 100, and the fastening member 120 can be configured to fasten the mask unit 100 and the support unit 110 through the fastening hole 104.

[0073] Figure 6 This is a cross-sectional view of the battery cell before welding using the welding fixture according to an embodiment of this disclosure. Figure 7 This is a cross-sectional view of a battery cell after welding using a welding fixture according to an embodiment of this disclosure, and Figure 8 This is a perspective view of a manifold to be welded using a welding fixture according to an embodiment of the present disclosure.

[0074] Reference Figure 6 and Figure 7 The battery cell 20 welded by the welding fixture 10 according to an embodiment of the present disclosure may include an electrode assembly 210, a battery canister 220, and a current collector. The battery cell 20 may include both a positive current collector 240 and a negative current collector 230, but for ease of explanation, the following description focuses on the case where the current collector is the negative current collector 230.

[0075] Reference Figure 6 and Figure 7 The electrode assembly 210 includes a positive electrode plate, a negative electrode plate, and a separator inserted between the positive and negative electrode plates, and may have a structure in which the positive electrode plate, the negative electrode plate, and the separator inserted between the positive and negative electrode plates are wound in one direction. Furthermore, the electrode assembly 210 has a central hole formed at the center and may be formed as a wound core type.

[0076] For example, the electrode assembly 210 can be manufactured by winding a laminate formed by sequentially stacking a negative electrode plate, a separator, a positive electrode plate, and a separator at least once. Here, the positive and negative electrode plates can be formed in sheet form.

[0077] In other words, the electrode assembly 210 used in this embodiment can be a wound electrode assembly. In this case, an additional diaphragm can also be provided on the outer peripheral surface of the electrode assembly 210 to insulate it from the battery canister 220. That is, the electrode assembly 210 can have a wound structure well known in the prior art without limitation.

[0078] The positive electrode active material is applied to one or both surfaces of the positive electrode plate, and a first uncoated portion 211 without the application of the positive electrode active material can be formed at the end of the positive electrode plate. Figure 6 and Figure 7A positive electrode plate with a first uncoated portion 211 formed is shown, but the battery cell 20 according to embodiments of the present disclosure includes embodiments with a positive electrode plate without the first uncoated portion 211 formed. However, for ease of explanation, the following description focuses on the case where the first uncoated portion 211 is formed on the positive electrode plate. The first uncoated portion 211 is exposed to the outside of the separator while forming multiple coils around the center of the electrode assembly 210, and it can itself serve as an electrode tab.

[0079] The negative electrode active material is applied to one or both surfaces of the negative electrode plate, and a second uncoated portion 212 without the negative electrode active material can be formed at the end of the negative electrode plate. Figure 6 and Figure 7 A negative electrode plate with the second uncoated portion 212 formed is shown, but the battery cell 20 according to embodiments of the present disclosure includes embodiments with a negative electrode plate without the second uncoated portion 212 formed. However, for ease of explanation, the following description focuses on the case where the second uncoated portion 212 is formed on the negative electrode plate. The second uncoated portion 212 is exposed to the outside of the separator while forming multiple coils around the center of the electrode assembly 210, and it can itself serve as an electrode tab.

[0080] In other words, at least one of the positive electrode plate and the negative electrode plate may each include an uncoated portion at the long side end in the winding direction where no active material is coated. Furthermore, the first uncoated portion 211 and the second uncoated portion 212 may be configured to face opposite directions.

[0081] Here, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate can be used without restriction, as long as they are active materials known in the art.

[0082] Furthermore, the membrane can be a porous polymer membrane, for example, a porous polymer membrane made alone or in a stacked structure of a polyolefin-based polymer such as ethylene homopolymer, propylene homopolymer, ethylene / butene copolymer, ethylene / hexene copolymer and ethylene / methacrylate copolymer.

[0083] As another example, the diaphragm can be a conventional porous nonwoven fabric, such as a nonwoven fabric made of high-melting-point glass fiber, polyethylene terephthalate fiber, etc.

[0084] At least one surface of the membrane may include a coating of inorganic particles. Furthermore, the membrane itself may be formed from the coating of inorganic particles. The particles constituting the coating may have a structure bonded to an adhesive such that there are gap volumes between adjacent particles.

[0085] Furthermore, the central hole of the electrode assembly 210 is also used for welding the cell terminal 250 (positive terminal) and the positive current collector 240. That is, the electrode assembly can be configured to weld the cell terminal 250 and the positive current collector 240 by irradiating a laser through the central hole of the electrode assembly 210.

[0086] refer to Figure 6 and Figure 7 The electrode assembly 210 is housed within the battery canister 220. For example, the battery canister 220 is formed in a cylindrical shape (with the electrode assembly 210 housed inside the battery canister 220) and can be electrically connected to the negative electrode plate of the electrode assembly 210. Therefore, the battery canister 210 can have the same polarity as the negative electrode plate, i.e., negative polarity.

[0087] Here, the diameter of the battery can 220 is larger than the diameter of the electrode assembly 210. A predetermined gap is formed between the battery can 220 and the positive current collector 240, and the insulator 260 can be inserted into this gap.

[0088] If the size of the electrode assembly 210 increases while the size of the battery can 220 is determined according to the standard, the total capacity of the battery cell 20 increases, but the gap between the battery can 220 and the electrode assembly 210 decreases.

[0089] In other words, if the size of the electrode assembly 210 is increased to increase the total capacity of the battery cell 20, the gap between the battery can 220 and the electrode assembly 210 decreases. Therefore, in order to increase the capacity of the battery cell 20, the insulator 260 should be inserted into the reduced gap between the battery can 220 and the electrode assembly 210. For this purpose, it is preferable that the thickness of the insulator 260 is as thin as possible.

[0090] Opening 221 (see Figure 6 Electrode assembly 210 can be formed in battery can 220. Electrode assembly 210 is accommodated through opening 221 formed in battery can 220, and electrolyte can also be injected into battery can 220.

[0091] Here, the battery canister 220 is a generally cylindrical container with an opening 221, and can be made of a conductive material such as metal. The material of the battery canister 220 can be a conductive metal, such as aluminum, steel, stainless steel, etc., but is not limited to this.

[0092] A through-hole can be formed in the battery canister 220, and the cell terminal 250 is connected to the through-hole and electrically connected to the positive current collector 240 through the through-hole. Furthermore, an insulator 260 can be inserted between the battery canister 220 and the positive current collector 240.

[0093] like Figure 6 and Figure 7As shown, the crimped portion and the crimped portion may not be formed in the battery can 220. Typically, the crimped portion of the battery can 220 is formed to fix the cover to the battery can 220, and the crimped portion of the battery can 220 is formed by pressing the outer periphery of the battery can 220 inward to support the electrode assembly 210, so that the electrode assembly 210 will not fall out of the battery can 220.

[0094] When the rolled edge and the crimped part are not formed in the battery can 220, the cover can be directly welded to the battery can 220 by seam welding.

[0095] In this way, by directly welding the cap to the battery canister 220 using a seam welding method, the fixing structure is simple, which further ensures the volume of the electrode assembly 210 to be housed within the battery canister 220. Consequently, compared to a battery canister 220 of the same volume, it is more advantageous to ensure the electrical capacity, which has the effect of improving energy density. In addition, it can prevent various process errors caused by the crimped and pressed portions from occurring.

[0096] Meanwhile, as will be described in detail later, the battery cell 20 welded by the welding fixture 10 according to the embodiments of this disclosure omits the cover used in conventional battery cells 20, and the negative current collector 230 has the function of a cover.

[0097] refer to Figure 6 and Figure 7 The negative current collector 230 is electrically connected to the negative electrode plate of the electrode assembly 210. When the second uncoated portion 212 is formed on the negative electrode plate, the negative current collector 230 is connected to the second uncoated portion 212 of the electrode assembly 210.

[0098] The negative electrode current collector 230 is made of a conductive metal material such as aluminum, steel, copper, or nickel, and can be electrically connected to the second uncoated portion 212 of the negative electrode plate. Furthermore, the negative electrode current collector 230 can be electrically connected to the battery canister 220.

[0099] The negative current collector 230 can be directly connected to the battery canister 220 by means such as welding (e.g., seam welding). Reference Figure 6 and Figure 7 Each of the two ends of the negative current collector 230 is bent upward and connected to the inner surface of the battery canister 220.

[0100] Here, in one embodiment, the negative current collector 230 may have the function of closing the opening 221 formed in the battery can 220.

[0101] In the case of a conventional cylindrical battery cell, the electrode assembly is housed in the battery can, a negative current collector is provided connected to the negative plate of the electrode assembly, and a cover is attached to the battery can to close the opening of the battery can.

[0102] However, in the battery cell 20 welded by the welding fixture 10 according to an embodiment of the present disclosure, the cover provided in a conventional cylindrical battery cell is removed, and the negative current collector 230 functions as a cover. That is, the negative current collector 230 is electrically connected to the electrode assembly 210 to function as a conventional current collector, and furthermore, the negative current collector 230 is directly connected to the battery canister 220 to function as a cover provided in a conventional battery cell.

[0103] In other words, the battery cell 20 welded by the welding fixture 10 according to the embodiments of this disclosure does not have a cover, and the negative electrode current collector 230, which has the function of a cover, is exposed to the outside.

[0104] Thus, when the negative current collector 230 with the function of a cover comes into contact with the electrode assembly 210, the protrusion 102 of the mask unit 100 of the welding fixture 10 according to the embodiment of the present disclosure is inserted into the recess 231 of the negative current collector 230, and welding is performed through the welding hole 101 in a close contact state.

[0105] However, this disclosure is not necessarily limited thereto, and the welding fixture 10 according to the embodiments of this disclosure can be applied to the welding of the negative current collector of a battery cell in which a cover is provided separately.

[0106] refer to Figure 8 The negative current collector 230 may include at least one bridging portion 233. Multiple bridging portions 233 may be provided, and for example, three may be provided. Figure 8 As shown, but this disclosure is not limited thereto.

[0107] refer to Figure 8 The bridging portion 233 can extend from the center portion 234 of the negative current collector 230 toward the peripheral portion 235. Furthermore, the bridging portion 233 can be formed to separate two adjacent weld portions 232. With this structure, the bridging portion 233 can enhance the rigidity of the negative current collector 230.

[0108] The positive current collector 240 is made of a conductive metallic material and is connected to the first uncoated portion 211 of the electrode assembly 210. The positive current collector 240 can be coupled to a connection surface formed by bending the end of the first uncoated portion 211 in a direction parallel to the positive current collector 240. The bending direction of the first uncoated portion 211 can be, for example, towards the winding center of the electrode assembly 210.

[0109] When the first uncoated portion 211 has the curved shape described above, the space occupied by the first uncoated portion 211 is reduced, which can increase the energy density. In addition, due to the increase in the bonding area between the first uncoated portion 211 and the positive current collector 240, the bonding strength can be improved and the resistance can be reduced.

[0110] The cell terminal 250 is made of a conductive metal material and is connected to a through hole in the battery canister 220 to be electrically connected to the positive current collector 240 through the through hole. Furthermore, the cell terminal 250 is electrically connected to the positive electrode plate of the electrode assembly 210 through the positive current collector 240, thus possessing positive polarity.

[0111] In other words, the cell terminal 250 can be used as the positive terminal. And, as described above, the battery canister 220 is electrically connected to the negative plate of the electrode assembly 210, thus having negative polarity.

[0112] An insulator 260 is inserted between the battery can 220 and the positive current collector 240 for insulation. The insulator 260 prevents contact between the battery can 220 and the positive current collector 240. Furthermore, the insulator 260 can be made of a material with insulating properties.

[0113] Figure 9 This is a schematic view illustrating the configuration of a battery pack including battery cells produced using welding fixtures according to each embodiment of this disclosure.

[0114] refer to Figure 9 The battery pack 30 according to embodiments of the present disclosure may include one or more battery cells 20. Here, the battery cells 20 are manufactured using the welding fixture 10 according to each embodiment of the present disclosure as described above.

[0115] In addition, the battery pack 30 may also include a battery pack housing 31 for accommodating the battery cells 20, and various devices for controlling the charging and discharging of the battery cells 20, such as a BMS, a current sensor, a fuse, etc.

[0116] Figure 10 It is used to describe including Figure 9 A view of the vehicle with its battery pack.

[0117] refer to Figure 10 The vehicle 40 according to embodiments of this disclosure may include one or more battery cells 20 or battery packs 30 produced using welding fixtures 10 according to each embodiment of this disclosure. Here, vehicle 40 includes various vehicles designed to use electricity, such as electric vehicles or hybrid vehicles.

[0118] The directional terms used herein (such as up, down, left, and right) are used for ease of description only, and it will be apparent to those skilled in the art that the terms may vary depending on the position of the element or the observer.

[0119] While this disclosure has been described above with reference to a limited number of embodiments and accompanying drawings, it is not limited thereto, and it will be apparent to those skilled in the art that various modifications and changes can be made to these embodiments within the technical aspects of this disclosure and within the equivalent scope of the appended claims. Therefore, the embodiments disclosed above should be considered illustratively rather than restrictively. That is, the scope of the true technical concept of this disclosure is shown in the claims, and all differences within the equivalent scope should be interpreted as including in this disclosure.

[0120] Industrial applicability

[0121] This disclosure relates to a welding fixture and a battery cell produced using the welding fixture, as well as a battery pack and vehicle including the cell, and is particularly applicable to the secondary battery industry.

Claims

1. A welding fixture for welding an electrode assembly and a current collector in a battery cell, the battery cell including the electrode assembly, a battery can housing the electrode assembly, and the current collector electrically connected to the electrode assembly, the welding fixture comprising: A mask unit having a recess or a protrusion formed on the current collector plate, a protrusion or recess formed on the mask unit corresponding to the recess or protrusion of the current collector plate, and a welding hole for welding formed in the mask unit; as well as A support unit, wherein the mask unit is connected to and supported by the support unit.

2. The welding fixture according to claim 1, in, An opening is formed in the battery can. The collector plate has the function of sealing the opening, and The protrusion or recess of the mask unit is tightly connected to the recess or protrusion of the manifold.

3. The welding fixture according to claim 2, in, The welding hole is formed in the mask unit corresponding to at least one of the plurality of recesses or protrusions formed on the manifold.

4. The welding fixture according to claim 1, in, The current collector is a negative current collector.

5. The welding fixture according to claim 1, in, The mask unit has an insertion groove formed to allow insertion at each of the two ends of the manifold.

6. The welding fixture according to claim 5, in, The end of the current collector and the battery can are inserted together into the insertion groove.

7. The welding fixture according to claim 6, in, Each of the two ends of the current collector is bent upward and connected to the inner surface of the battery can, and the current collector and the battery can are inserted together into the insertion groove with the current collector connected to the inner surface of the battery can.

8. The welding fixture according to claim 1, in, Multiple recesses or protrusions are formed on the current collector plate, at least one of the recesses or protrusions having its opposite surface in contact with the electrode assembly, and the remaining recesses or protrusions having their opposite surfaces spaced apart from the electrode assembly. The welding hole is formed in the mask unit at a position corresponding to the portion of the manifold that contacts the electrode assembly.

9. The welding fixture according to claim 8, in, The weld portion is formed on the manifold at the portion corresponding to the weld hole of the mask unit.

10. The welding fixture according to claim 1, in, Bridging portions, in the form of protrusions or recesses, are formed on the manifold to enhance its rigidity. The bridging portion is spaced apart from the electrode assembly, and The mask unit has recesses or protrusions formed thereon to make close contact with the bridging portion.

11. The welding fixture according to claim 10, in, The size of the welding hole is larger than the size of the bridging portion.

12. The welding fixture according to claim 1, in, Fastening holes are formed in the mask unit, and The fastening component fastens the mask unit and the support unit through the fastening hole.

13. A battery cell produced using a welding fixture according to any one of claims 1 to 12.

14. A battery pack comprising at least one battery cell according to claim 13.

15. A vehicle comprising at least one battery cell according to claim 13.

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