Apparatus and method for manufacturing secondary battery, and secondary battery

Abstract

Disclosed are an apparatus and a method for manufacturing a secondary battery, and a secondary battery manufactured using the apparatus and / or the method. The apparatus for manufacturing a secondary battery includes: a roller configured to apply a force in a first direction to at least a portion of a tab extending from an electrode assembly to form a preliminary bent portion in at least the portion of the tab; and a tab pusher configured to apply a force to the tab in a second direction different from the first direction such that the tab has a shape of a number '11' centered on the preliminary bending portion.

Description

TECHNICAL FIELD

[0001] Aspects of embodiments of the present disclosure relate to an apparatus and a method for manufacturing a secondary battery and a secondary battery manufactured using the apparatus and / or method. BACKGROUND

[0002] In recent years, as electronic devices using batteries, such as mobile phones, notebook computers, and electric vehicles, are rapidly spreading, the demand for high-energy-density and high-capacity secondary batteries is rapidly increasing. Accordingly, research and development to improve the performance of lithium secondary batteries are actively being conducted.

[0003] A lithium secondary battery is a battery including a positive electrode and a negative electrode, each of which includes an active material capable of intercalating and deintercalating lithium ions, and an electrolyte, and generates electric energy through an oxidation-reduction reaction that occurs when lithium ions intercalate into and deintercalate from the positive electrode and the negative electrode.

[0004] A secondary battery includes an electrode assembly in which a positive electrode, a negative electrode, and a separator are stacked. The secondary battery includes a tab extending from the electrode assembly to allow the electrode assembly to be electrically connected to the outside. In addition, the secondary battery includes a case that accommodates the electrode assembly. The tab is partially located inside the case and is partially exposed to the outside of the case. In this case, there can be a problem in that the tab located inside the case occupies a large portion of the volume of the case. For example, the tab located inside the case can be formed in a U shape in the case, and thus there can be a problem in that the bending quality is deteriorated and an upper space allowance inside the case cannot be secured. SUMMARY

[0005] According to an aspect of one or more embodiments of the present application, the bending quality of the tab is improved.

[0006] According to another aspect of one or more embodiments of the present application, an internal space allowance of the case is secured.

[0007] However, the problems and aspects to be addressed by the present application are not limited to the above-mentioned problems and aspects to be addressed, and other problems and aspects to be addressed not mentioned can be clearly understood by those skilled in the art from the following description.

[0008] According to one or more embodiments of the present application, an apparatus for manufacturing a secondary battery includes a roller configured to apply a force to at least a portion of a tab extending from an electrode assembly in a first direction to form a preliminary bending portion in at least the portion of the tab, and a tab pusher applying a force to the tab in a second direction different from the first direction so that the tab has a shape of a number "11" centered on the preliminary bending portion.

[0009] According to one or more embodiments of the present application, a method of manufacturing a secondary battery includes forming a preliminary bent portion in at least a portion of a tab extending from an electrode assembly by applying a force to the at least a portion of the tab in a first direction, and forming the tab into a shape of a numeral "11" centered on the preliminary bent portion by applying a force to the tab in a second direction different from the first direction.

[0010] According to one or more embodiments of the present application, a secondary battery includes a case, an electrode assembly accommodated in the case, and a tab extending from the electrode assembly and connected to a lead tab exposed to an outside of the case, wherein the tab is bent along a preliminary bent portion in the case. BRIEF DESCRIPTION OF DRAWINGS

[0011] The following drawings included in the present specification illustrate several example embodiments of the present application and, together with the detailed description given later, serve to further understand the technical spirit of the present application; however, the present application should not be construed as being limited to details in the drawings:

[0012] Figures 1-4 is a view each schematically illustrating a lithium secondary battery according to an embodiment;

[0013] Figures 5A-5C is a sequence diagram illustrating a conventional apparatus and / or method for manufacturing a secondary battery;

[0014] Figure 6 is an image illustrating a conventionally manufactured tab;

[0015] Figure 7 is a flowchart illustrating a method of manufacturing a secondary battery according to an embodiment of the present application;

[0016] Figure 8A and Figure 8B is a schematic diagram illustrating a process of manufacturing a secondary battery according to an embodiment of the present application;

[0017] Figures 9A-9D is a schematic diagram illustrating a process of manufacturing a secondary battery according to an embodiment of the present application;

[0018] Figures 10A-10C is a schematic diagram illustrating an apparatus and / or method for manufacturing a secondary battery according to an embodiment of the present application; and

[0019] Figure 11A and Figure 11B is an image illustrating a tab manufactured according to an embodiment of the present application. DETAILED DESCRIPTION

[0020] In this document, one or more embodiments of the present application will be described in detail with reference to accompanying drawings. However, these embodiments are presented as examples, and the present application is not limited by the same, and the present application should be defined by the scope of the claims. The terms or words used in the specification and claims should not be interpreted as being limited to common meanings or dictionary meanings, and should be interpreted as having meanings and concepts consistent with the technical idea of the present application based on the principle that the inventor is able to properly define the terms. Accordingly, the configurations described herein and shown in the drawings are provided as some example embodiments, and do not represent the entire technical spirit of the present application, and thus it should be understood that various equivalents and modifications can be made at the time of filing the present application.

[0021] In addition, "include" or "comprise" used in the specification can specify the presence of the described shape, number, step, operation, component, element, and / or group thereof, and does not exclude the presence or addition of one or more other shapes, numbers, steps, operations, components, elements, and / or groups thereof.

[0022] In addition, the drawings can not be illustrated in actual proportions for the convenience of understanding the present application. Rather, the size of some components can be exaggerated. In addition, the same reference numerals can be assigned to the same components in different embodiments.

[0023] In addition, when a component is described as "connected", "coupled", or "proximate" to another component, the components can be directly connected, coupled, or proximate to each other, or one or more other components can be "interposed" between the components, or the components are "connected", "coupled", or "proximate" through another component.

[0024] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, the use of "may" in describing the embodiments of the present disclosure means one or more embodiments of the present disclosure. The terms "one or more of" and "at least one of," when succeeding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

[0025] Unless otherwise specified herein, when a component such as a layer, film, region, or plate is described as being "on" another component, this includes not only the case where the component is "directly" on the other component, but also the case where one or more other components are interposed therebetween.

[0026] Unless otherwise specified herein, a singular expression can also include a plural meaning. In addition, unless otherwise specified, "A or B" can mean "including A, including B, or including A and B."

[0027] For ease of description, spatially relative terms, such as "beneath", "below", "lower", "above", "upper", and the like, can be used herein for describing an element's or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if a device is inverted or flipped over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the term "below" can encompass both an orientation of above and below. The devices can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0028] As used herein, the term "combination thereof can mean a mixture, a laminate, a composite, a copolymer, an alloy, a blend, a reaction product, or the like of the components.

[0029] Figures 1-4 are each a view illustrating a lithium secondary battery according to an embodiment.

[0030] Lithium secondary battery 100

[0031] The lithium secondary battery 100 can be classified into a cylindrical battery, a prismatic battery, a pouch-type battery, and a coin-type battery according to its shape. Figures 1-4 are each a view illustrating a lithium secondary battery according to an embodiment, and it can be said that Figure 1 a cylindrical battery is illustrated, Figure 2 a prismatic battery is illustrated, Figure 3 and Figure 4 a pouch-type battery is illustrated. Referring to Figures 1-4 , the lithium secondary battery 100 can include an electrode assembly 40 including a positive electrode 10, a negative electrode 20, and a separator 30 interposed between the positive electrode 10 and the negative electrode 20, and a case 50 accommodating the electrode assembly 40. The positive electrode 10, the negative electrode 20, and the separator 30 can be impregnated with an electrolyte (not shown). In an embodiment, as shown in Figure 1 , the lithium secondary battery 100 can include a sealing member 60 sealing the case 50. In an embodiment, as shown in Figure 2 , the lithium secondary battery 100 can include a positive electrode lead tab 11, a positive electrode terminal 12, a negative electrode lead tab 21, and a negative electrode terminal 22. In an embodiment, as shown in Figure 3 and Figure 4 , the lithium secondary battery 100 can include a lead tab 70 (i.e., a positive electrode lead tab 71 and a negative electrode lead tab 72) serving as an electrical path to lead current formed in the electrode assembly 40 to the outside.

[0032] As referred to in Figures 1-4The lithium secondary battery 100 includes an electrode assembly 40 and a case 50 that accommodates the electrode assembly 40. The electrode assembly 40 is electrically connected to the outside, and charges and / or discharges (supplies) electric energy to the outside by an external source. In an embodiment, the lithium secondary battery 100 includes tabs that are electrically connected to the outside.

[0033] The tabs include electrode tabs. The electrode tabs are formed to extend from the electrode assembly 40. The tabs include a negative electrode tab connected to the negative electrode 20 of the electrode assembly 40 and a positive electrode tab connected to the positive electrode 10 of the electrode assembly 40. The electrode tabs extend from the electrode assembly 40 and are positioned inside the case 50. In an embodiment, the electrode tabs are each, for example, a base material tab extending from a base material of the positive electrode 10 or the negative electrode 20

[0034] The electrode tabs are connected to the lead tabs 71 and 72 to be electrically connected to the outside. In an embodiment, the lead tabs 71 and 72 are partially positioned inside the case 50, and the other part is exposed to the outside of the case 50.

[0035] In an embodiment, the electrode tabs extend from each of the negative electrode 20 and the positive electrode 10 included in the electrode assembly 40, and are formed in a plurality of numbers. Accordingly, it is desirable to effectively accommodate the electrode tabs in the case 50. In addition, it is desirable that the electrode tabs are shaped to be easily connected to the lead tabs 71 and 72. To this end, a process of effectively accommodating and / or organizing the electrode tabs in the case 50 will be described below.

[0036] Figures 5A-5C is a sequence diagram illustrating a conventional apparatus and / or method for manufacturing a secondary battery.

[0037] Figure 6 is an image illustrating a conventionally manufactured tab.

[0038] As described with reference to Figures 1-6 , the secondary battery includes an electrode assembly 310 (e.g., including the electrode assembly 40 shown in Figures 1-4 ) and a case 330 (e.g., including the case 50 shown in Figures 1-4 ) that accommodates the electrode assembly 310, and a tab 320 (e.g., including the electrode tab shown in Figures 3-4 ) extending from the electrode assembly 310.

[0039] The tab 320 is accommodated in the case 330, and can be subjected to a taping, overlapping, cutting, bonding, and / or bending process to be connected to a lead tab 340 (e.g., including the lead tab shown in Figures 3-4The terminal 320 is connected to the lead terminal 340 via the lead terminal 71 and 72 shown in FIG. 1. Via this, the terminal 320 is connected to the lead terminal 340. At this time, the terminal 320 can be connected to the lead terminal 340, for example, by soldering.

[0040] Further, the lead terminal 340 is partially located inside the housing 330, while another part is exposed to the outside of the housing 330. At this time, in order to control the degree of exposure of the lead terminal 340 to the outside of the housing 330, a pushing process is performed to push the terminal 320 connected to the lead terminal 330 into the housing 330. Further, in order to ensure that the terminal 320 is smoothly inserted into the housing 330 during the pushing process, a bending process of bending a part of the terminal 320 is further performed. The bending process is a process of forming a V-shaped bent part in a part of the terminal 320. The bending process is a process of partially bending the terminal 320 by force to form a V-shaped bent part. Figures 5A-5C is a schematic view of a pushing process performed after such a bending process is performed.

[0041] Figure 5A A process of providing a tape 341 on the lead terminal 340 is exemplified. The tape 341 is formed to surround at least a part of the lead terminal 340. The tape 341 is provided for attachment between the lead terminal 340 and the housing 330. The tape 341 includes, for example, a polypropylene (PP) tape.

[0042] Figure 5B A process of inserting the lead terminal 340 into the housing 330 by the terminal pusher 220 is exemplified. The terminal pusher 220 is connected to the other side of the lead terminal 340, and applies force to the lead terminal 340. For example, the terminal pusher 220 pushes the lead terminal 340 toward the housing 330 (for example, applies force in the direction indicated by PF in FIG. 1). Figure 5B

[0043] Figure 5C ​A sealing process that fixes the lead tab 340 having the tape 341 provided thereon to the case 330 is exemplified. When the lead tab 340 is properly inserted into the case 330, the tab pusher 220 stops (completes) pushing the lead tab 340. When the pushing of the tab pusher 220 is completed, the sealing top 201 and the sealing bottom 202 apply a force toward the case 330. For example, the sealing top 201 applies a force in a downward direction (PD direction) from above the opening of the case 330 toward the case 330. Simultaneously (e.g., concurrently) or sequentially, the sealing bottom 202 applies a force in an upward direction (PU direction) from below the opening of the case 330 toward the case 330. At this time, the PD direction in which the sealing top 201 moves and the PU direction in which the sealing bottom 202 moves are opposite directions. Also, the sealing top 201 and the sealing bottom 202 are positioned to face each other and move toward each other. At this time, the lead tab 340 that straddles the inside and outside of the case 330 is located at the opening of the case 330. The sealing top 201 and the sealing bottom 202 apply a force toward the opening of the case 330, so that the lead tab 340 is fixed to the opening of the case 330. For example, the tape 341 that surrounds the lead tab 340 is fixed to the case 330.

[0044] At this time, as the tab pusher 220 pushes the lead tab 340 toward the case 330, the bent portion of the tab 320 can be deformed, as shown in Figure 5B and Figure 5C Figure 5B and Figure 5C The indicator bu in

[0045] Figure 6 exemplifies such deformation of the bent portion of the tab 320. For example, when the tab 320 receives a force, the bent portion can not maintain a V-shape and can be deformed to form a U-shaped bent portion bu.

[0046] In this case, as shown in FIGS. 5 and Figure 6 , the tab 320 that forms the U-shaped bent portion occupies a large volume in the upper side space (e.g., a space in the direction of the opening of the case) of the case 330. Accordingly, the tab 320 unnecessarily wastes the upper side space.

[0047] According to one or more embodiments of the present application, improved U-shapes of the tab 320 and / or increased utilization of the upper space of the case 330 will be described in greater detail herein.

[0048] Figure 7 is a flowchart exemplifying a method of manufacturing a secondary battery according to an embodiment of the present application.

[0049] ​Figure 8A and Figure 8B is a schematic diagram illustrating a process of manufacturing a secondary battery according to an embodiment of the present application.

[0050] The method of manufacturing a secondary battery according to an embodiment of the present application includes performing an additional process between the taping process and the preliminary welding process to improve the U-shape of the tab 320. The additional process includes, for example, a preliminary bending portion forming process of forming a preliminary bending portion 321 (see Figure 8A and Figure 8B ) in the tab 320. In Figure 7 , Figure 8A and Figure 8B , the additional process and an apparatus for performing the additional process will be described.

[0051] As shown in Figure 8A and Figure 8B , the apparatus 200 for manufacturing a secondary battery according to an embodiment of the present application includes a roller 210. In addition, for example, the apparatus 200 for manufacturing a secondary battery further includes a tab pusher 220 (e.g., including the tab pusher 220 shown in Figures 5A-5C In an embodiment, for example, the apparatus 200 for manufacturing a secondary battery can further include a support 230 and a conveying portion 240.

[0052] The roller 210 applies a force to at least a portion of the tab 320 in a first direction to form the preliminary bending portion 321. For example, the roller 210 applies a force to at least a portion of the tab 320 extending from the electrode assembly 310 in the first direction to form the preliminary bending portion 321 in at least the portion of the tab 320. The first direction is, for example, a direction parallel to the direction P in which the electrode assembly 310 moves. However, the roller 210 can form the preliminary bending portion 321 by applying a force to at least a portion of the tab in a direction opposite to the first direction. For example, the roller 210 can form the preliminary bending portion 321 by applying a force in a direction opposite to the direction P in which the electrode assembly 310 moves. That is, the roller 210 can form the preliminary bending portion 321 on the tab 320 located on the groove 231 from any direction along the groove 231. In addition, even if the groove 231 is not formed, the roller 210 can form the preliminary bending portion 321 on the tab 320 while moving on the tab 320 in the first direction or in a direction opposite to the first direction.

[0053] In an embodiment, a jig (not shown) applies a force to the tab 320 in a second direction different from the first direction to form the preliminary bending portion 321 as a bending portion. The second direction is, for example, a direction perpendicular to the first direction.

[0054] The tab pusher 220 applies force to the tab 320 in a second direction different from the first direction to form the tab 320 into the shape of the number "11" centered at the bent portion. Figure 7 As shown, the method of manufacturing a secondary battery according to an embodiment of the present invention includes operation S101 of applying a force to at least a portion of the tab 320 in a first direction by a roller 210 to form a preliminary bent portion 321 .

[0055] For example, the roller 210 may be moved in a first direction toward the electrode assembly 310 (eg, including Figures 1-4 The electrode assembly 40 and / or Figures 5A-6 The electrode assembly 310 shown in FIG. 3 is provided with a tab 320 (eg, including Figure 4 The electrode tabs and / or Figures 5A-6 A force is applied to at least a portion of the terminal tab 320 as shown to form a preliminary bent portion 321 on at least the portion of the terminal tab 320.

[0056] In one embodiment, the first direction is a direction perpendicular to the direction in which the tab 320 extends. Figures 1-4 The positive electrode 10 and the negative electrode 20 shown in FIG are extended to form a terminal tab 320. The electrode includes a base material and an active material layer formed on at least a portion of the base material. The portion of the base material in the electrode on which the active material layer is formed is called a coated portion. The portion of the electrode on which the active material layer is not formed is called an uncoated portion. The terminal tab 320 is included in the uncoated portion. For example, the terminal tab 320 is an uncoated portion in the form of a plate. The first direction is the direction in which the terminal tab 320 moves on the plate-shaped surface and is perpendicular to the direction in which the terminal tab 320 extends.

[0057] Operation S101 includes rolling the roller 210 (see Figure 8A and Figure 8B ) forms a preliminary bent portion 321 on the tab 320 while being rotated in the first direction.

[0058] For example, operation S101 includes forming the terminal piece 320 with the groove 231 (see FIG. Figure 8B ) of the support member 230 (see Figure 8A and Figure 8B ) moves in the first direction.

[0059] In one embodiment, if Figure 8AAs shown, one or more electrode assemblies 310a are provided on the transfer portion 240. The transfer portion 240 transfers the electrode assembly 310a located on the transfer portion 240 toward the roller 210. In an embodiment, the support 230 is located below the roller 210. In an embodiment, the support 230 is formed at the same height as the height of the transfer portion 240 without a step, and / or is positioned slightly lower than the transfer portion 240 with a step from the transfer portion 240. The support 230 is located at one side of the transfer portion 240. Accordingly, as the electrode assembly 310a is transferred through the transfer portion 240, the tab 320a extending from the electrode assembly 310a can be placed on the support 230. In addition, the roller 210 is stepped with the transfer portion 240 and is positioned higher than the transfer portion 240. In an embodiment, the roller 210 can be opened or closed. When the roller 210 is in the open state, the roller 210 is in contact with and located on the transfer portion 240. When the roller 210 is in the closed state, the roller 210 is spaced apart from the transfer portion 240. In an embodiment, the roller 210 can move away from (closed state) or close to (open state) the support 230 while rotating about a point. In another embodiment, the roller 210 can move away from (closed state) or close to (open state) the support 230 while moving perpendicular to the support 230. For example, the transfer portion 240 can transfer the electrode assembly 310a in the P direction. At the same time, the transfer portion 240 can transfer the tab 320a toward the support 230. Figure 8A and Figure 8B As shown, the electrode assemblies 310a, 310b are located on the transfer portion 240, and the tabs 320a, 320b extending from the electrode assemblies 310a, 310b are located outside the side of the transfer portion 250. Accordingly, as the electrode assemblies 310a, 310b are transferred through the transfer portion 240, the tabs 320a, 320b can be placed on the support 230. In addition, the roller 210 is stepped with the transfer portion 240 and is positioned higher than the transfer portion 240. In an embodiment, the roller 210 can be opened or closed. When the roller 210 is in the open state, the roller 210 is in contact with and located on the transfer portion 240. When the roller 210 is in the closed state, the roller 210 is spaced apart from the transfer portion 240. In an embodiment, the roller 210 can move away from (closed state) or close to (open state) the support 230 while rotating about a point. In another embodiment, the roller 210 can move away from (closed state) or close to (open state) the support 230 while moving perpendicular to the support 230. For example, the transfer portion 240 can transfer the electrode assembly 310a in the P direction. At the same time, the transfer portion 240 can transfer the tab 320a toward the support 230.

[0060] In addition, for example, the operation S101 can include rotating the roller 210 along the groove 231 while applying a force to the tab 320 placed on the support 230 to form a preliminary bending portion 321. For example, as shown in FIG. 2B, the roller 210 is rotated along the groove 231 while applying a force to the tab 320 placed on the support 230 to form a preliminary bending portion 321. Figure 8BAs shown, the transfer part 240 transfers the electrode assembly 310b to the front of the support 230. Accordingly, the tab 320b is placed on the support 230. When the tab 320b is placed on the support 230, the roller 210 is in an open state and approaches the support 230. The roller 210 rotates in a direction (e.g., a clockwise direction r or a counterclockwise direction) to form a preliminary bent portion 321 on the tab 320b. In an embodiment, the roller 210 includes a protrusion protruding along an outer peripheral surface thereof at a portion in contact with the tab 320b. The protrusion forms the preliminary bent portion 321 on the tab 320b while rotating along a groove 231 formed in the support 230. In an embodiment, the groove 231 is a recessed portion formed in an upper surface of the support 230 and is formed to correspond to the preliminary bent portion 321. Accordingly, the groove 231 can be a recessed portion formed in the upper surface of the support 230 in the first direction.

[0061] In an embodiment, for example, the preliminary bent portion 321 is formed at a position 0.2 mm (inclusive) to 0.8 mm (inclusive) apart from the electrode assembly 310 in a direction in which the tab 320 extends.

[0062] In an embodiment, the electrode assembly 310 includes a portion up to a coated portion formed on each electrode. For example, the length of the negative electrode coated portion, the length of the positive electrode coated portion, and the length of the separator can be different. Accordingly, the end portion of the electrode assembly 310 can have an uneven shape due to the negative electrode coated portion (having a side connected to the negative electrode tab as a negative electrode uncoated portion), the positive electrode coated portion (having a side connected to the positive electrode tab as a positive electrode uncoated portion), and / or the separator. In this case, the end portion of the electrode assembly 310 can mean an average position of the end portions of each of the negative electrode coated portion, the positive electrode coated portion, and the separator.

[0063] In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.2 mm to 0.7 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.2 mm to 0.6 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.3 mm to 0.8 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.3 mm to 0.7 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.4 mm to 0.8 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.4 mm to 0.7 mm from the electrode assembly 310. In one embodiment, for example, the preliminary bend portion 321 is formed at a distance of 0.4 mm to 0.6 mm from the electrode assembly 310.

[0064] Through these processes, the lithium secondary battery 100 manufactured by the method and / or apparatus for manufacturing a secondary battery according to an embodiment of the present invention may provide the tab 320 formed with the preliminary bent portion 321 .

[0065] like Figure 7 As shown, the method for manufacturing a secondary battery according to an embodiment of the present invention includes operation S102 of performing a bending process on the tab 320 to form a bent portion. For example, a jig performs the bending process on the tab 320. In one embodiment, the bending process includes, for example, a block bending process, a roller bending process, etc. The jig includes an upper jig located above the tab 320 and a lower jig located below the tab 320. The upper jig descends toward the tab 320. In addition, for example, the lower jig ascends toward the tab 320. At this time, the upper jig and the lower jig may descend and ascend toward the tab 320 synchronously (e.g., simultaneously). The upper jig and the lower jig may push the joined tab 320 toward the electrode assembly. In another embodiment, the upper jig may descend toward the tab 320, and then the lower jig may ascend toward the tab 320. In one embodiment, the lower jig may apply a force toward a position on the tab 320 that is offset from the upper jig. In one embodiment, the lower clamp may be raised toward the tab 320 and then push the tab 320 toward the electrode assembly. Thus, the preliminary bent portion 321 is formed into a bent portion. For example, the bent portion may be formed into a V-shape.

[0066] like Figure 7As illustrated, in the method of manufacturing a secondary battery according to an embodiment of the present application, a force is applied to the tab 320 in a second direction different from the first direction, so that the tab 320 forms a shape of a numeral "11" centered on the bent portion. The shape of the numeral "11" includes a shape in which one side of the bent tab 320 and the other side of the bent tab 32 are formed in parallel or almost in parallel with respect to the bent portion. For example, the one side and the other side of the tab 320 can be formed to have an angle of 0° ~ 40° with respect to each other based on the bent portion.

[0067] The second direction is a direction opposite to a direction in which the tab 320 extends. The second direction is, for example, a direction toward the electrode assembly 310.

[0068] For example, the operation S103 includes accommodating the electrode assembly 310 and the tab 320 extending from the electrode assembly 310 in the case 330. Accordingly, the case 330 accommodates the electrode assembly 310, the tab 320, and a portion of the lead tab 340 connected to the tab 320. Further, the operation S103 includes applying a force to the tab 320 in the second direction toward the case 330.

[0069] Accordingly, even though the force is applied in the second direction by the tab pusher, the tab 320 can form the shape of the numeral "11", thereby improving the bending quality and / or securing the upper space margin. Further, the lead tab 340 can be properly exposed to the outside of the case 330. It will be referred to Figures 9A-9D The operation S102 will be described in more detail.

[0070] Through this, the method and / or apparatus for manufacturing a secondary battery according to an embodiment of the present application can improve the tab 320 bent in a U shape while effectively utilizing the upper space of the case 330.

[0071] Figures 9A-9D is a schematic view illustrating a process of manufacturing a secondary battery according to an embodiment of the present application.

[0072] Figure 9A illustrates an electrode assembly 310 of a lithium secondary battery 100 according to an embodiment of the present application and a tab 320 extending from the electrode assembly 310.

[0073] Figure 9B illustrates a state in which the roller 210 is in an open state Figure 9A The tab 320 is illustrated. In an embodiment, as Figure 9B As illustrated, the roller 210 includes a protrusion 211 formed along an outer circumferential surface of one side thereof.

[0074] Figure 9CThe example roller 210 moves in a first direction along a groove 231 formed in the support 230 while rotating to form a preliminary bent portion 321 on the tab 320.

[0075] Figure 9D The example bent tab 320 forms a shape of a number "11" centered on the preliminary bent portion 321. As shown, Figure 9D when the tab pusher 220 (see Figures 5A-5C ) pushes the lead tab 340 toward the case (omitted in the drawing for convenience of description), Figures 9A-9D the tab 320 forms a bent portion along the preliminary bent portion 321. Further, the tab 320 forms a shape of a number "11" centered on the bent portion. Accordingly, the tab 320 can not form a U-shaped bent portion.

[0076] In an embodiment, a first portion 321a of the tab 320 facing one side of the bent portion (formed by the preliminary bent portion 321) and a second portion 321b of the tab 320 facing the other side of the bent portion can be formed to have an angle of 20° ~ -20° with respect to each other. For example, the first portion 321a and the second portion 321b can be formed in a V shape having an angle of 40° centered on the bent portion. In an embodiment, for example, the first portion 321a and the second portion 321b can be formed to have an angle of 0° with respect to each other. In this case, the first portion 321a and the second portion 321b can be formed in a shape of a number "11" or a shape very close to a number "11"

[0077] The first portion 321a is a region of the tab 320. The first portion 321a is, for example, a region from the electrode assembly 310 to the bent portion.

[0078] The second portion 321b is another region of the tab 320. The second portion 321b is, for example, a region from the bent portion to the lead tab 340.

[0079] Through this, the device and the method for manufacturing a secondary battery according to an embodiment of the present application and / or the secondary battery manufactured thereby can effectively utilize a space inside the case 330.

[0080] Figures 10A-10C is a schematic view illustrating a device and / or a method for manufacturing a secondary battery according to an embodiment of the present application.

[0081] Figure 11A and Figure 11B are images illustrating a tab manufactured according to an embodiment of the present application.

[0082] Figure 10AThe example electrode assembly 310 and the tab 320 formed with the preliminary bent portion 321 are accommodated in the case 330. In an embodiment, the tab 320 is connected to the lead tab 340. At least a portion of the lead tab 340 can be surrounded by the tape 341.

[0083] In an embodiment, the preliminary bent portion 321 is shaped, for example, as shown in Figure 11A and / or Figure 11B In an embodiment, the preliminary bent portion 321 is a groove formed from the upper surface of the tab 320 at a depth of 50% to 200% of the thickness of the tab 320, as shown in Figure 11A and / or Figure 11B In an embodiment, the preliminary bent portion 321 is a groove formed from the upper surface of the tab 320 at a depth of 50% to 200% of the thickness of the tab 320, as shown in

[0084] Figure 10B The example tab pusher 220 pushes the lead tab 340 toward the case 330 in the second direction PF while applying a force to the tab 320. Accordingly, the tab 320 is bent based on the bent portion bent in a V shape along the preliminary bent portion 321 to form a bent portion b11 in the shape of a number "11".

[0085] Figure 10C The example lead tab 340 is fixed to the case 330 as the sealing top 201 descends (in the PD direction) and the sealing bottom 202 ascends (in the PU direction).

[0086] As can be seen through Figure 10A , Figure 10B and Figure 10C According to embodiments of the present application, a secondary battery in which an upper space of a case 330 can be effectively utilized and / or a U-shaped bent portion of a tab 320 can be improved, and a method of manufacturing the same are provided.

[0087] In one or more embodiments, an apparatus for manufacturing a secondary battery according to embodiments of the present application and a secondary battery manufactured by a method of manufacturing a secondary battery are provided, and the secondary battery includes Figures 1-4 the components described above. Herein, the components included in the secondary battery will be described in more detail.

[0088] Positive electrode active material

[0089] As the positive electrode active material, a compound capable of reversibly intercalating and deintercalating lithium (lithiated intercalation compound) can be used. In an embodiment, one or more of a composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0090] The composite oxide may be a lithium transition metal composite oxide, examples of which may include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0091] As an example, a compound represented by any of the following chemical formulas can be used: Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b- c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g Gg PO4(0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3(0≤f≤2); or Li a FePO4(0.90≤a≤1.8).

[0092] In the above chemical formula, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 is Mn, Al, or a combination thereof.

[0093] As an example, the positive electrode active material can be a high-nickel-based positive electrode active material having a nickel content of greater than or equal to 80 mol%, greater than or equal to 85 mol%, greater than or equal to 90 mol%, greater than or equal to 91 mol%, or greater than or equal to 94 mol% and less than or equal to 99 mol% based on 100 mol% of metals other than lithium in a lithium transition metal complex oxide. The high-nickel-based positive electrode active material enables high capacity, and can be applied to a high-capacity and high-density lithium secondary battery.

[0094] The positive electrode 10

[0095] The positive electrode 10 for the lithium secondary battery 100 can include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer includes a positive electrode active material, and can further include a binder and / or a conductive material.

[0096] As an example, the positive electrode can further include an additive capable of being used as a sacrificial positive electrode.

[0097] In an embodiment, the content of the positive electrode active material can be 90 wt% to 99.5 wt% based on 100 wt% of the positive electrode active material layer, and the content of each of the binder and the conductive material can be 0.5 wt% to 5 wt% based on 100 wt% of the positive electrode active material layer.

[0098] The binder adheres positive electrode active material particles to each other well, and also adheres the positive electrode active material to the current collector well. Representative examples of the binder include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, a polymer containing an oxirane, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, epoxy resin, (meth)acrylic resin, polyester resin, nylon, and the like, but the present application is not limited thereto.

[0099] The conductive material provides electrical conductivity to the electrode, and any suitable material that does not cause chemical changes and is electrically conductive can be used in the configured battery. Examples of the conductive material can include: a carbon-based material such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fiber, carbon nanofiber, or carbon nanotube; a metal-based material in the form of a metal powder or a metal fiber including copper, nickel, aluminum, silver, or the like; a conductive polymer such as a polyaniline derivative; or a mixture thereof.

[0100] In an embodiment, Al can be used as the current collector, but the present application is not limited thereto.

[0101] Negative electrode active material

[0102] The negative electrode active material can include a material capable of reversibly intercalating and deintercalating lithium ions, lithium metal, a lithium metal alloy, a material capable of doping and undoping lithium, or a transition metal oxide.

[0103] The material capable of reversibly intercalating and deintercalating lithium ions is a carbon-based negative electrode active material, and can include, for example, crystalline carbon, amorphous carbon, and / or a combination thereof. Examples of the crystalline carbon can include graphite such as amorphous, plate-like, flaky, spherical, or fibrous natural graphite or artificial graphite. Examples of the amorphous carbon can include soft carbon or hard carbon, mesophase pitch carbide, calcined coke, or the like.

[0104] In an embodiment, the lithium metal alloy can be an alloy of lithium and a metal selected from Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al, and Sn.

[0105] The Si-based negative electrode active material or the Sn-based negative electrode active material can be used as the material capable of doping and undoping lithium. The Si-based negative electrode active material can include silicon, a silicon-carbon composite, SiO x(0 < x < 2), Si-Q alloy (wherein Q is selected from alkali metals, alkaline earth metals, Group 13 elements, Group 14 elements (excluding Si), Group 15 elements, Group 16 elements, transition metals, rare earth elements, and combinations thereof), or a combination thereof. The Sn-based negative electrode active material can be Sn, SiO2, a Sn-based alloy, or a combination thereof.

[0106] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to an embodiment, the silicon-carbon composite can be in the form of secondary particles in which silicon primary particles are accumulated, and amorphous carbon coating layers (shells) on surfaces of the secondary particles. In an embodiment, the amorphous carbon can be located between the silicon primary particles, such that, for example, the silicon primary particles can be coated with the amorphous carbon. The secondary particles can be dispersed in an amorphous carbon matrix.

[0107] The silicon-carbon composite can further include crystalline carbon. For example, the silicon-carbon composite can include a core including crystalline carbon and silicon particles, and an amorphous carbon coating layer on a surface of the core.

[0108] The Si-based negative electrode active material or the Sn-based negative electrode active material can be used in mixture with a carbon-based negative electrode active material.

[0109] Negative electrode 20

[0110] The negative electrode 20 for the lithium secondary battery 100 includes a current collector and a negative electrode active material layer on the current collector. The negative electrode active material layer can include a negative electrode active material, and can further include a binder and / or a conductive material.

[0111] In an embodiment, for example, the negative electrode active material layer can include 90 wt% to 99 wt% of the negative electrode active material, 0.5 wt% to 5 wt% of the binder, and 0 wt% to 5 wt% of the conductive material.

[0112] The binder well adheres the negative electrode active material particles to each other, and also well adheres the negative electrode active material to the current collector. A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used as the binder.

[0113] In an embodiment, the non-aqueous binder can include polyvinyl chloride, carboxylated polyvinyl chloride, polyfluoroethylene, ethylene propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide imide, polyimide, or a combination thereof.

[0114] The aqueous binder can be selected from styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluoro rubber, polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphazene, poly(meth)acrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0115] If the aqueous binder is used as a negative electrode binder, a cellulose-based compound capable of providing adhesion can be further included. As the cellulose-based compound, one or more of carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, and alkali metal salts thereof can be used in combination. In an embodiment, Na, K, or Li can be used as the alkali metal.

[0116] The dry binder is a polymeric material capable of fibrillation, and can be, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, or combinations thereof.

[0117] The conductive material provides electrical conductivity to the electrode, and any suitable material that does not cause chemical changes and is electrically conductive can be used in the configured battery. Examples of the conductive material can include: carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fibers, or carbon nanofibers; metal-based materials in the form of metal powders or metal fibers including copper, nickel, aluminum, silver, etc.; conductive polymers such as polyaniline derivatives; or mixtures thereof.

[0118] In an embodiment, the negative electrode current collector can be selected from copper foil, nickel foil, stainless steel foil, titanium foil, foamed nickel, foamed copper, a polymer substrate coated with a conductive metal, and combinations thereof.

[0119] Electrolyte

[0120] The electrolyte for the lithium secondary battery 100 can include a non-aqueous organic solvent and a lithium salt.

[0121] The non-aqueous organic solvent is a medium through which ions participating in the electrochemical reaction of the battery can move.

[0122] The non-aqueous organic solvent can be a carbonate-based solvent, an ester-based solvent, an ether-based solvent, a ketone-based solvent, an alcohol-based solvent, an aprotic solvent, or combinations thereof.

[0123] The carbonate-based solvent can include any one of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), ethyl methyl carbonate (MEC), ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), etc.

[0124] The ester-based solvent can include any one of methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate, decanolide, methyl hydroxypivalate, valerolactone, caprolactone, and the like.

[0125] The ether-based solvent can include any one of dibutyl ether, tetraethylene glycol dimethyl ether, diglyme, dimethoxyethane, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, tetrahydrofuran, and the like. In addition, the ketone-based solvent can include cyclohexanone, and the like. The alcohol-based solvent can include ethanol, isopropyl alcohol, and the like, and the aprotic solvent can include: a nitrile such as R-CN (wherein R is a C2 to C20 linear, branched, or cyclic hydrocarbon group, and includes a double bond, an aromatic ring, or an ether bond), and the like; an amide such as dimethylformamide; a dioxolane such as 1,3-dioxolane and 1,4-dioxolane; a sulfolane; and the like.

[0126] The non-aqueous organic solvent can be used alone, or two or more can be used in combination.

[0127] In an embodiment, if a carbonate-based solvent is used, a cyclic carbonate and a chain carbonate can be mixed and used, and the cyclic carbonate and the chain carbonate can be mixed in a volume ratio of 1:1 to 1:9.

[0128] The lithium salt is a material that is dissolved in the non-aqueous organic solvent and is a source of lithium ions in the battery, and enables the basic operation of the lithium secondary battery, and improves the movement of lithium ions between the positive electrode and the negative electrode. Representative examples of the lithium salt can include one or two or more selected from LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiAlO2, LiAlCl4, LiPO2F2, LiCl, LiI, LiN(SO3C2F5)2, Li(FSO2)2N (lithium bis(fluorosulfonyl)imide, LiFSI), LiC4F9SO3, LiN(C x F 2x+1 SO2)(C y F 2y+1 SO2)(wherein x and y are integers of 1 to 20), lithium trifluoromethanesulfonate, lithium tetrafluoroethanesulfonate, lithium difluorobis(oxalato)phosphate (LiDFBOP), and lithium bis(oxalato)borate (LiBOB).

[0129] The separator 30

[0130] The separator 30 can be present between the positive electrode 10 and the negative electrode 20 depending on the type of the lithium secondary battery 100. The separator 30 can include a polyethylene, a polypropylene, a polyvinylidene fluoride, or a multi-layer film of two or more layers thereof, and in an embodiment, the separator can include a hybrid multi-layer film such as a polyethylene / polypropylene double-layer separator, a polyethylene / polypropylene / polyethylene triple-layer separator, a polypropylene / polyethylene / polypropylene triple-layer separator, or the like.

[0131] The separator 30 can include a porous substrate and a coating layer on one surface or both or opposite surfaces of the porous substrate, the coating layer including an organic material, an inorganic material, or a combination thereof.

[0132] The porous substrate can be a polymer film formed of a polymer selected from a polyolefin such as polyethylene, polypropylene, or the like, a polyester such as polyethylene terephthalate, polybutylene terephthalate, or the like, a polyacetal, a polyamide, a polyimide, a polycarbonate, a polyether ether ketone, a polyaryletherketone, a polyetherimide, a polyamideimide, a polybenzimidazole, a polyethersulfone, a polyphenylene ether, a cyclic olefin copolymer, a polyphenylene sulfide, a polyethylene naphthalate, glass fiber, and polytetrafluoroethylene (e.g., Teflon), or a copolymer or mixture of two or more thereof.

[0133] The organic material can include a polyvinylidene fluoride-based polymer or a (meth)acrylic-based polymer.

[0134] The inorganic material can include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but the present application is not limited thereto.

[0135] The organic material and the inorganic material can be present by being mixed in one coating layer, or can be present in a stacked form of a coating layer including the organic material and a coating layer including the inorganic material.

[0136] The apparatus and method for manufacturing a secondary battery according to one or more embodiments and the secondary battery can provide improved bending quality of the secondary battery.

[0137] In addition, the apparatus and method for manufacturing a secondary battery according to one or more embodiments and the secondary battery can secure a space allowance of the secondary battery.

[0138] However, those skilled in the art will appreciate that aspects and effects that can be achieved by the present application are not limited to those described herein, and other aspects, effects, and advantages of the present application will be more clearly understood from the detailed description.

[0139] Although some example embodiments of the present application have been described above, the present application is not limited thereto and various modifications can be made within the scope of the claims and the detailed description of the present application and the drawings, and these modifications should be understood to also belong to the scope of the present application.

Claims

1.An apparatus for manufacturing a secondary battery, the apparatus comprising: a roller configured to apply a force to at least a portion of a tab extending from an electrode assembly in a first direction to form a preliminary bent portion in at least the portion of the tab; and a tab pusher configured to apply a force to the tab in a second direction different from the first direction so that the tab has a shape of a number "11" centered on the preliminary bent portion. 2.The apparatus of claim 1, wherein the first direction is a direction perpendicular to a direction in which the tab extends, and the roller is configured to form the preliminary bent portion while rotating on the tab in the first direction. 3.The apparatus of claim 1, further comprising a support including a groove formed in an upper surface thereof in the first direction, wherein the roller is configured to rotate along the groove while applying a force to the tab placed on the support to form the preliminary bent portion. 4.The apparatus of claim 1, wherein the preliminary bent portion is formed at a position 0.2mm to 0.8mm apart from the electrode assembly in a direction in which the tab extends. 5.The apparatus of claim 1, wherein the second direction is a direction opposite to a direction in which the tab extends, and the tab pusher is configured to apply a force toward the electrode assembly in the second direction. 6.The apparatus of claim 1, further comprising a jig configured to apply a force to the tab so that the tab forms a bent portion along the preliminary bent portion, wherein the tab pusher is configured to allow the tab to form the shape of the number "11" centered on the bent portion. 7.A method of manufacturing a secondary battery, the method comprising: forming a preliminary bent portion in at least a portion of a tab extending from an electrode assembly by applying a force to the at least the portion of the tab in a first direction; and forming the tab into a shape of a number "11" centered on the preliminary bent portion by applying a force to the tab in a second direction different from the first direction. 8.The method of claim 7, wherein the first direction is a direction perpendicular to a direction in which the tab extends, and the forming the preliminary bent portion includes forming the preliminary bent portion while a roller rotates on the tab in the first direction. 9.The method of claim 7, wherein the forming the preliminary bent portion includes: moving the tab onto a support formed with a groove in the first direction; and forming the preliminary bent portion by rotating a roller along the groove while applying a force to the tab placed on the support. 10.The method of claim 7, wherein the preliminary bent portion is formed at a position 0.2mm to 0.8mm apart from the electrode assembly in a direction in which the tab extends. ​ ​ 11.The method of claim 7, wherein the second direction is a direction opposite to a direction in which the tab extends. 12.The method of claim 7, wherein the forming the tab in a shape of the number "11" comprises: accommodating the electrode assembly and the tab extending from the electrode assembly in a case; and applying a force to the tab in the second direction toward the case. 13.A secondary battery comprising: a case; an electrode assembly accommodated in the case; a tab extending from the electrode assembly and connected to a lead tab exposed to an outside of the case, wherein the tab is bent in the case along a preliminary bending portion. 14.The secondary battery of claim 13, wherein the tab includes a first portion facing one side of the preliminary bending portion and a second portion facing the other side of the preliminary bending portion, the first portion and the second portion having an angle of 20° to -20° with respect to each other. 15.The secondary battery of claim 14, wherein the first portion and the second portion form a shape of the number "11". 16.The secondary battery of claim 13, wherein the preliminary bending portion is formed at a position 0.2 mm to 0.8 mm apart from the electrode assembly in a direction in which the tab extends. ​

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