Insert device

Abstract

An insert device according to an embodiment of the present invention is an insert device for inserting an electrode assembly unit, including an electrode assembly and a first current collector coupled to one surface of the electrode assembly, into a battery can, and comprises: a can holder for holding the battery can; a lower stopper that supports the electrode assembly unit from below and can move in a direction parallel to the central axis of the electrode assembly unit; and an air blower that is provided in the lower stopper and can inject air into the electrode assembly unit in the direction of the battery can.

Description

Insert device

[0001] The present invention relates to an insert device. More specifically, the present invention relates to an insert device for inserting an electrode assembly into a battery can.

[0002] This application claims priority to Korean Patent Application No. 10-2023-0191776, filed December 26, 2023, and Korean Patent Application No. 10-2024-0039950, filed March 22, 2024, the entire contents of which are disclosed in the specification and drawings of the above applications are incorporated herein by reference.

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

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

[0005] Meanwhile, in the cylindrical secondary battery manufacturing process, an insertion process is performed to insert an electrode assembly into the battery can. During the insertion process, the electrode assembly is inserted into the battery can from the bottom to the top.

[0006] Meanwhile, some electrode assembly insertion devices, such as those for conventional 4680 and 4695 cells, have a disadvantageous structure in the process due to the release of air inside the can, which causes the electrode assembly core reform to loosen. In addition, the phenomenon of the core reform being loosened in the post-processing work caused various problems. In addition, there was a problem that the separator was damaged and the battery capacity and lifespan were reduced during CRW (Cathode Rivet Welding). More specifically, the separator was deformed due to irregular core movement caused by the positive electrode collector at the bottom of the electrode assembly.

[0007] Accordingly, the present invention is intended to solve the above problem, and a primary purpose of the present invention is to prevent deformation of the separator by reducing pressure through air injection when discharging air inside a battery can during an electrode assembly insertion process.

[0008] In addition, another object of the present invention is to improve battery capacity and lifespan by improving core impingement by reducing the level of reform loosening.

[0009] In addition, another purpose of the present invention is to reduce damage to the electrode assembly separator and improve process efficiency.

[0010] Furthermore, the present invention has another purpose of reducing costs.

[0011] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0012] According to one embodiment of the present invention for solving the above-described problem, an insert device is provided for inserting an electrode assembly assembly including an electrode assembly and a first current collector coupled to one surface of the electrode assembly into a battery can, the insert device comprising: a can holder for holding the battery can; a lower stopper for supporting the electrode assembly assembly from below and configured to be movable in a direction parallel to a central axis of the electrode assembly assembly; and an air blower provided on the lower stopper and configured to be capable of injecting air into the electrode assembly assembly in a direction toward the battery can.

[0013] In one aspect of the present invention, the first current collector may be bonded to a surface of the electrode assembly facing the battery can.

[0014] Preferably, the first collector may have an area smaller than the area of ​​one side of the electrode assembly.

[0015] In one aspect of the present invention, the lower stopper may be configured to insert the electrode assembly into the battery can.

[0016] Preferably, the lower stopper may be configured to push the electrode assembly assembly, which is positioned lower than the can, upwardly so as to push the electrode assembly assembly toward the opening of the battery can.

[0017] In another aspect of the present invention, the air blower may be configured to inject air toward the winding center of the electrode assembly.

[0018] Preferably, the air blower may be configured to inject air in the insertion direction of the electrode assembly.

[0019] More preferably, the air blower may be configured to inject air from downward to upward in a direction parallel to the central axis of the electrode assembly.

[0020] In another aspect of the present invention, the air blower may be configured to offset pressure acting on a winding center hole area of ​​the electrode assembly.

[0021] In another aspect of the present invention, the air blower may be configured to inject air so that the difference between the internal pressure of the battery can and the external pressure of the battery can is 5 mbar or less.

[0022] In another aspect of the present invention, the air blower may be configured to operate after the electrode assembly is inserted a predetermined length in the longitudinal direction of the battery can.

[0023] Preferably, the air blower may be configured to operate after the electrode assembly is inserted 1 / 3 of the way in the longitudinal direction of the battery can.

[0024] In another aspect of the present invention, the air blower may be configured to inject air so that the diameter of the winding center after deformation of the electrode assembly assembly is greater than 75% of the diameter of the winding center before deformation of the electrode assembly assembly.

[0025] Preferably, the air blower may be configured to inject air so that the pressure inside the battery can is lower than a value at which the shape of the winding center of the electrode assembly is not deformed.

[0026] According to the present invention, when air is discharged from inside a battery can during an electrode assembly insertion process, deformation of the separator can be prevented by reducing pressure through air injection.

[0027] In addition, according to the present invention, by reducing the level of reforming looseness, the battery capacity and lifespan can be improved by improving core impact.

[0028] In addition, according to the present invention, damage to the electrode assembly separator can be reduced and process capability can be improved.

[0029] Furthermore, cost reduction can be achieved according to the present invention.

[0030] However, the effects that can be obtained through the present invention are not limited to the effects described above, and other technical effects that are not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0032] FIG. 1 is a drawing for explaining an insert device according to one embodiment of the present invention.

[0033] FIG. 2 is a drawing for explaining the process of inserting an electrode assembly into a battery can in the insert device of FIG. 1.

[0034] Figure 3 is a drawing for explaining the process of inserting the electrode assembly into the battery can.

[0035] Figure 4 is a drawing for explaining the movement of air during the process of inserting the electrode assembly into the battery can.

[0036] FIG. 5 is a drawing for explaining the direction in which air is injected into the electrode assembly when air movement such as that in FIG. 4 occurs.

[0037] FIG. 6 is a drawing for explaining the process in which air injected into the electrode assembly moves into the inside of the electrode assembly when air movement such as that in FIG. 4 occurs.

[0038] Fig. 7 is a drawing for explaining the area where the electrode assembly is affected by air during the process of Figs. 4 to 6.

[0039] Fig. 8 is a drawing for explaining a state in which the electrode assembly is deformed by being affected by air during the process of Figs. 4 to 6.

[0040] FIG. 9 is a drawing for explaining a process in which air is injected into an electrode assembly and a battery can by an air blower in an insert device according to one embodiment of the present invention.

[0041] FIG. 10 is a drawing for explaining an air movement path by an air blower in an insert device according to one embodiment of the present invention.

[0042] FIG. 11 is an enlarged view of the winding center hole of an electrode assembly inserted into a battery can by an insert device according to one embodiment of the present invention.

[0043] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that conforms to the technical spirit of the present invention.

[0044] Therefore, it should be understood that the embodiments described in this specification and the configurations illustrated in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, and that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0045] Additionally, to aid understanding of the invention, the attached drawings are not drawn to scale and the dimensions of some components may be exaggerated.

[0046]

[0047] In the cylindrical secondary battery manufacturing process, an insertion process is performed to insert an electrode assembly (EA) into a battery can (C). During the insertion process, the electrode assembly (EA) is inserted into the battery can (C) from the bottom to the top. Meanwhile, some electrode assembly (E) insertion devices, such as those for conventional 4680 and 4695 cells, are disadvantageous in the process due to the occurrence of core reforming of the electrode assembly (E) due to the discharge of air inside the can. The reforming process is a process of processing the separator located in the core of the electrode assembly (E) to secure a circular space in the core. In addition, the phenomenon of core reforming loosening in the post-processing process caused various problems. In addition, there was a problem of separator damage, reduced battery capacity, and lifespan during CRW (Cathode Rivet Welding, the welding process of the cathode assembly and terminal). More specifically, the separator deformation occurred due to irregular core movement caused by the cathode current collector located at one end of the electrode assembly (E).

[0048] The present invention recognizes that such a problem occurs and is configured to include an air blower that injects air into the insert device (1). The specific structure of the present invention will be described in detail with reference to FIGS. 1 to 11 below.

[0049]

[0050] FIG. 1 is a drawing for explaining an insert device (1) according to one embodiment of the present invention, and FIG. 2 is a drawing for explaining a process in which an electrode assembly assembly (EA) is inserted into a battery can (C) in the insert device (1) of FIG. 1. FIG. 3 is a drawing for explaining a process in which an electrode assembly assembly (EA) is inserted into a battery can (C).

[0051] Referring to FIGS. 1 and 2, an insert device (1) according to one embodiment of the present invention includes a can holder (10), a lower stopper (20), and an air blower (30). The insert device (1) may be an insert device (1) that inserts an electrode assembly assembly (EA) including an electrode assembly (E) and a first current collector (P1) coupled to one surface of the electrode assembly (E) into a battery can (C).

[0052] More specifically, the insert device (1) may include a can holder (10) that holds the battery can (C); a lower stopper (20) that supports the electrode assembly assembly (EA) from below and is configured to move in a direction parallel to the central axis of the electrode assembly assembly (EA); and an air blower (30) that is provided on the lower stopper (20) and is configured to be capable of injecting air toward the battery can (C) with respect to the electrode assembly assembly (EA).

[0053] According to this structure, when the air inside the battery can (C) is discharged during the electrode assembly (E) insertion process, deformation of the separator can be prevented by reducing the pressure through air injection. In addition, according to the structure, by reducing the level of reform loosening, the battery capacity and lifespan can be improved by improving core collision. Accordingly, damage to the separator of the electrode assembly (E) can be reduced and the process capability can be improved.

[0054]

[0055] In one aspect of the present invention, the electrode assembly assembly (EA) may include an electrode assembly (E), a first current collector (P1), and a second current collector (P2). That is, the electrode assembly assembly (EA) may be in a state in which the first current collector (P1) and the second current collector (P2) are coupled to the electrode assembly (E).

[0056] The electrode assembly (E) includes a first electrode having a first polarity, a second electrode having a second polarity, and a separator interposed between the first electrode and the second electrode. The first electrode is an anode or a cathode, and the second electrode corresponds to an electrode having a polarity opposite to that of the first electrode.

[0057] The electrode assembly (E) may have, for example, a jelly-roll structure. That is, the electrode assembly (E) may be manufactured by stacking a first electrode plate and a second electrode plate in a sheet shape at least once with a separator interposed therebetween, and winding the stack in one direction based on the winding center hole (H1). In this case, an additional separator may be provided on the outer circumferential surface of the electrode assembly (E) for insulation from the battery can (C). Any jelly-roll structure known in the art may be applied to the present invention without limitation.

[0058] The first electrode includes a first electrode plate and a first electrode active material applied on one or both surfaces of the first electrode plate. A first uncoated portion, on which the first electrode active material is not applied, exists at one end in the width direction of the first electrode plate. The first uncoated portion, which functions as a first electrode tab, is hereinafter referred to as a first uncoated portion. The first uncoated portion is provided at an upper portion in the height direction of an electrode assembly (E) accommodated in a battery can (C). That is, the first electrode plate includes a first uncoated portion, on which an active material layer is not coated at a long end and which is exposed to the outside of a separator, and a part of the first uncoated portion is used as an electrode tab in its own right. The first uncoated portion may be, for example, a positive electrode tab.

[0059] Meanwhile, at least a portion of the first non-conductive portion may include a plurality of segments divided along the winding direction of the electrode assembly (E). In this case, the plurality of segments may be bent along the radial direction of the electrode assembly (E). The plurality of bent segments may be overlapped in multiple layers. In this case, the first current collector (P1) described below may be coupled to an area where the plurality of segments are overlapped in multiple layers.

[0060] The second electrode includes a second electrode plate and a second electrode active material applied on one or both surfaces of the second electrode plate. A first uncoated portion, on which the second electrode active material is not applied, exists at the other end in the width direction of the second electrode plate. The first uncoated portion, which functions as a second electrode tab, is hereinafter referred to as a second uncoated portion. The second uncoated portion is provided at a lower portion in the height direction of the electrode assembly (E) accommodated in the battery can (C). That is, the second electrode plate includes a second uncoated portion, on which an active material layer is not coated at a long end and which is exposed to the outside of the separator, and at least a portion of the second uncoated portion is used as an electrode tab in its own right. The second uncoated portion may be, for example, a positive electrode tab. Meanwhile, at least a portion of the second uncoated portion may include a plurality of segments divided along the winding direction of the electrode assembly (E). In this case, the plurality of segments may be bent along the radial direction of the electrode assembly (E). The above-described plurality of folded segments may be overlapped in multiple layers. In this case, the second current collector (P2) may be bonded to the region where the plurality of segments are overlapped in multiple layers. In the present invention, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate may be used without limitation as long as they are active materials known in the art.

[0061]

[0062] The above battery can (C) may be configured to include an opening (C1) on one side and receive the electrode assembly (E) through the opening (C1).

[0063] Specifically, the battery can (C) is a roughly cylindrical container having an opening (C1) formed at the bottom, and is made of a conductive material such as metal, for example. The material of the battery can (C) may be, for example, steel, stainless steel, or nickel-plated iron. The upper surface located opposite the opening (C1) is referred to as a closed portion (C2). The side wall portion and the closed portion (C2) of the battery can (C) may be formed integrally. Alternatively, the side wall portion and the closed portion (C2) of the battery can (C) may be provided separately and joined to each other by welding, etc. The upper surface (the surface parallel to the XY plane) of the battery can (C), i.e., the outer surface of the closed portion (C2), may have a roughly flat shape. The battery can (C) may accommodate the electrode assembly (E) through the opening portion (C1) formed at the bottom.

[0064] The above battery can (C) is electrically connected to the electrode assembly (E). The battery can (C) is electrically connected, for example, to the second non-conductive portion of the electrode assembly (E). In this case, the battery can (C) has the same polarity as the second non-conductive portion.

[0065] The first current collector (P1) is accommodated inside the battery can (C) and can be electrically connected to the electrode assembly (E). The first current collector (P1) may have, for example, a substantially plate shape. The first current collector (P1) may be interposed between the first non-conductive portion and the terminal (50). That is, the first current collector (P1) may have the same electrode as the first non-conductive portion. The first current collector (P1) may be bonded to a surface on which the first non-conductive portion is folded. The first current collector (P1) may be, for example, a positive current collector.

[0066] The second current collector (P2) is accommodated inside the battery can (C), is electrically connected to the electrode assembly (E), and can also be electrically connected to the battery can (C). That is, the second current collector (P2) electrically connects the electrode assembly (E) and the battery can (C). The second current collector (P2) may have, for example, an approximately plate shape. Preferably, the second current collector (P2) can be electrically coupled to the second non-conductive portion and the beading portion (21) of the battery can (C). The second current collector (P2) may be, for example, a negative current collector.

[0067] That is, the electrode assembly assembly (EA) may be configured in a structure in which a first current collector (P1) is bonded to one surface of the electrode assembly (E), and a second current collector (P2) is bonded to the opposite surface of the electrode assembly (E) to which the first current collector (P1) is bonded. For example, referring to FIG. 3, the first current collector (P1) may be bonded to the upper surface of the electrode assembly (E). More specifically, the first current collector (P1) may be bonded to a surface of the electrode assembly (E) that faces the battery can (C). Conversely, the second current collector (P2) may be bonded to a lower surface of the electrode assembly (E). The second current collector (P2) may be bonded to an opposite surface of the surface of the electrode assembly (E) that faces the battery can (C). At this time, the connection between the electrode assembly (E) and the current collector (P1, P2) may be, for example, by welding.

[0068]

[0069] The above insert device (1) can be configured to insert a jelly roll-shaped electrode assembly assembly (EA) into a cylindrical battery can (C) when manufacturing a cylindrical secondary battery.

[0070] Here, the can holder (10) may be configured to hold a battery can (C). The can holder (10) may have a shape capable of holding a cylindrical battery can (C). For example, the can holder (10) may be configured in the form of a pair of tongs having an inner surface dug into a cylindrical shape so as to be capable of holding a cylindrical shape. The can holder (10) may be configured to hold at least a portion of the length of the battery can (C). For example, referring to FIGS. 1 and 2, the can holder (10) may hold the battery can (C) at two points along the length of the battery can (C). However, it should be understood that the can holder (10) of the present invention is not limited to such a shape. Any can holder (10) capable of holding a battery can (C) may be included within the scope of the can holder (10) of the present invention.

[0071] In one aspect of the present invention, the can holder (10) can hold the can such that the opening (C1) of the can faces downward and the closing portion (C2) of the can faces upward. For example, referring to FIGS. 1 and 2, the can holder (10) holds the battery can (C) such that the opening (C1) of the battery can faces downward and the closing portion (C2) of the battery can (C) faces upward. That is, the electrode assembly assembly (EA) can be inserted into the opening (C1) of the battery can (C) provided at the lower portion of the battery can (C) and moved toward the closing portion (C2) provided at the upper portion of the battery can (C).

[0072] The reason why the opening (C1) of the battery can (C) is structured to face downward and the closing portion (C2) to face upward is to allow the electrode assembly (EA) to be inserted upward. For example, if the electrode assembly (EA) is inserted downward, a free-fall method can be adopted. However, this free-fall method has the problem that the insertion speed cannot be controlled and positive pressure is generated. On the other hand, the method of inserting the electrode assembly (EA) downward while holding it may unnecessarily complicate the structure of the can holder (10), which may lead to problems such as an increase in management points and a decrease in processability. Therefore, it is preferable that the electrode assembly (EA) be inserted upward, and according to the structure of the present invention, the electrode assembly (EA) can be inserted from the bottom to the top. Accordingly, it becomes possible to insert the electrode assembly (EA) while minimizing the generation of positive pressure with a simple structure. That is, according to the process of FIGS. 1 and 2, a battery can (C) can be supplied into an insert device (1) by a can holder (10) like this.

[0073]

[0074] Referring to FIGS. 1 and 2, the lower stopper (20) can be configured to insert the electrode assembly (EA) into the battery can (C).

[0075] Specifically, the lower stopper (20) may be configured to support the electrode assembly assembly (EA) from below. In addition, the lower stopper (20) may be configured to be movable in a direction parallel to the central axis of the electrode assembly assembly (EA). For example, the lower stopper (20) may push the electrode assembly assembly (EA) located below the can upward, thereby pushing the electrode assembly assembly (EA) toward the opening (C1) of the battery can (C). That is, the lower stopper (20) in the state of FIG. 1 may push the electrode assembly assembly (EA) upward. Accordingly, the electrode assembly assembly (EA) passes through the opening (C1) of the battery can (C) and rises toward the closing portion (C2) of the battery can (C), resulting in the state of FIG. 2.

[0076] In another aspect of the present invention, the lower stopper (20) may be configured in a roughly cylindrical shape. That is, the lower stopper (20) may be configured in a roughly elongated rod shape, and the central axis of the rod may coincide with the central axis of the electrode assembly (EA).

[0077] In one aspect of the present invention, the radius of the lower stopper (20) may be configured to be larger than the radius of the winding center hole (H1) of the electrode assembly assembly (EA). For example, the radius of the cylindrical lower stopper (20) may be configured to be slightly larger than the radius of the winding center hole (H1) of the electrode assembly assembly (EA).

[0078] According to this structure, since the radius of the lower stopper (20) is larger than the radius of the winding center hole (H1) of the electrode assembly assembly (EA), the lower stopper (20) can support the electrode assembly assembly (EA) and the second current collector (P2) from below. In addition, since the radius of the cylindrical lower stopper (20) is slightly larger than the radius of the winding center hole (H1) of the electrode assembly assembly (EA), the contact area between the lower stopper (20) and the electrode assembly assembly (EA) can be minimized. As a result, the possibility of damage to the electrode assembly assembly (EA) can be minimized.

[0079] In another embodiment, the radius of the lower stopper (20) may be configured to be larger than the radius of the second collector hole formed in the center of the second collector (P2) coupled to the electrode assembly assembly (EA). For example, the radius of the lower stopper (20) may be configured to be larger than the radius of the second collector hole and smaller than or equal to the radius of the center region of the second collector (P2).

[0080] According to this structure, since the radius of the lower stopper (20) is larger than the radius of the second collector hole, the lower stopper (20) can support the electrode assembly assembly (EA) and the second collector (P2) from below. In addition, since the radius of the lower stopper (20) is smaller than or equal to the radius of the central region of the second collector (P2), the leg portion of the second collector (P2) extending from the outer periphery of the central region may not be affected by the lower stopper (20).

[0081]

[0082] In another aspect of the present invention, the lower stopper (20) may include a polyetheretherketone (PEEK) material. According to this embodiment, damage to the lower stopper (20) may be minimized even when it comes into contact with the electrode assembly (EA) and / or the second current collector (P2).

[0083]

[0084] Referring again to FIGS. 1 and 2, the air blower (30) may be provided on the lower stopper (20). The air blower (30) may be configured to inject air toward the battery can (C) with respect to the electrode assembly (EA).

[0085] The above air blower (30) may include a positive pressure generator (31) that generates positive pressure and an air pipe (32) that can move air.

[0086] The positive pressure generator (31) may be, for example, a blower. Air generated from the positive pressure generator (31) may move toward the electrode assembly (EA) through the air pipe (32).

[0087] In one aspect of the present invention, the air pipe (32) may be configured to be built into the interior of the lower stopper (20). For example, referring to FIGS. 1 and 2, a cylindrical, tubular air pipe (32) may be provided within the cylindrical lower stopper (20). Accordingly, the air flow generated from the positive pressure generator (31) may travel along the air pipe (32) to reach the electrode assembly (E). More specifically, the air may be ejected toward the winding center hole (H1) of the electrode assembly (E).

[0088]

[0089] Fig. 4 is a drawing for explaining the movement of air during the process of inserting the electrode assembly assembly (EA) into the battery can (C). Fig. 5 is a drawing for explaining the direction in which air is injected into the electrode assembly assembly (EA) when the air movement as in Fig. 4 occurs, and Fig. 6 is a drawing for explaining the process in which air injected into the electrode assembly assembly (EA) moves into the inside of the electrode assembly (E) when the air movement as in Fig. 4 occurs.

[0090] Referring to FIGS. 4 and 5, by means of an insert device (1) according to one embodiment of the present invention, the electrode assembly assembly (EA) can be inserted upward toward the battery can (C). More specifically, as the lower stopper (20) supporting the electrode assembly assembly (EA) from below rises upward, the electrode assembly assembly (EA) can be inserted into the battery can (C). In the process, as shown in FIG. 4, air trapped inside the battery can (C) can be discharged to the outside of the battery can (C) through the winding center hole (H1) of the electrode assembly (E).

[0091] Meanwhile, as can be seen in Fig. 4, the first current collector (P1) is bonded to one surface of the electrode assembly (E). At this time, the first current collector (P1) may have an area smaller than the area of ​​one surface of the electrode assembly (E). For example, the first current collector (P1) may be a plate-shaped structure having an approximately circular shape and a partially open interior. However, the first current collector (P1) may have a shape in which the center portion is not open for welding connection with the terminal of the battery. In other words, since the center portion of the first current collector (P1) is closed, it may have a structure that covers the winding center hole (H1) of the electrode assembly (E). However, since welding is not performed on all surfaces where the electrode assembly (E) and the first current collector (P1) are in contact, a slight gap may exist between the first current collector (P1) and the electrode assembly (E). Therefore, as can be confirmed in Fig. 5, when air flows into the electrode assembly (E) through the open area of ​​the first current collector (P1), the introduced air can move toward the winding center hole (H1) of the electrode assembly (E) along the arrow path of Fig. 6. At this time, referring again to Figs. 4 and 6, since the diameter of the winding center hole (H1) of the electrode assembly (E) is significantly smaller than the diameter of the inside of the battery can (C), the flow velocity flowing through the winding center hole (H1) can increase relatively significantly.

[0092]

[0093] FIG. 7 is a drawing for explaining an area in which the electrode assembly (E) is affected by air during the process of FIGS. 4 to 6, and FIG. 8 is a drawing for explaining a state in which the electrode assembly (E) is affected by air and deformed during the process of FIGS. 4 to 6.

[0094] In another aspect of the present invention, since the separator forming the inside of the winding center hole (H1) has low rigidity due to its thin thickness and weak restraint due to contact with the core, the separator located inside the winding center hole (H1) may be deformed in the radial direction by the flow flowing in the total height direction. For example, referring to FIG. 7, air may flow in the direction of the arrow due to the shape of the first current collector (P1) into the separator located near the winding center hole (H1) of the electrode assembly (E). As a result, as shown in FIG. 8, the separator located inside the winding center hole (H1) may be deformed in the radial direction by the flow flowing in the total height direction. That is, near the winding center hole (H1) of the electrode assembly (E), flow resistance may occur due to a rapid change in diameter. Accordingly, the pressure (p1) inside the battery can (C) may increase.

[0095] For example, the cross-sectional area of ​​the battery can (C) is approximately 1,597.51 mm 2 And, the cross-sectional area of ​​the winding center hole (H1) of the electrode assembly (E) is approximately 75.84 mm. 2 , and assuming that PPM is about 130, and the insertion speed of the electrode assembly assembly (EA) is about 42.55 cm / s, the flow speed of the air flowing into the winding center hole (H1) of the electrode assembly (E) becomes about 896.28 cm / s, so it can be confirmed that the flow speed increases rapidly. That is, due to the flow speed that increases rapidly in this way, the separator located around the winding center hole (H1) may inevitably be deformed. However, according to the air blower (30) of the present invention, by significantly reducing the difference in the flow speed and the pressure (p1) inside the battery can (C), the deformation of the separator located around the winding center hole (H1) can be effectively prevented. This will be described in more detail with reference to FIGS. 9 to 11.

[0096]

[0097] FIG. 9 is a drawing for explaining a process in which air is injected into an electrode assembly (E) and a battery can (C) by an air blower in an insert device (1) according to an embodiment of the present invention, and FIG. 10 is a drawing for explaining an air movement path by an air blower in an insert device (1) according to an embodiment of the present invention. FIG. 11 is an enlarged drawing of a winding center hole (H1) of an electrode assembly (E) inserted into a battery can (C) by an insert device (1) according to an embodiment of the present invention.

[0098] In one aspect of the present invention, the air blower (30) may be configured to inject air toward the winding center hole (H1) of the electrode assembly (EA).

[0099] For example, referring to FIG. 9, an air pipe (32) is built into the interior of the lower stopper (20) that supports the lower surface of the electrode assembly (EA). Accordingly, air generated from the positive pressure generator (31) can be injected into the electrode assembly (EA) through the air pipe (32). More specifically, the air can be injected toward the winding center of the electrode assembly (E).

[0100] Preferably, the air blower (30) may be configured to inject air in the insertion direction of the electrode assembly assembly (EA). For example, referring to FIG. 9, the electrode assembly assembly (EA) may be inserted into the battery can (C) while moving upward from downward in a direction parallel to the central axis of the electrode assembly assembly (EA). Accordingly, the air blower (30) may be configured to inject air from downward to upward in a direction parallel to the central axis of the electrode assembly assembly (EA).

[0101]

[0102] In another aspect of the present invention, the air blower (30) may be configured to offset the pressure acting on the winding center hole (H1) area of ​​the electrode assembly (E).

[0103] For example, referring to FIG. 10, the air blower (30) can inject air toward the winding center hole (H1) of the electrode assembly (E). Meanwhile, if the cross-sectional area of ​​the battery can (C) and the cross-sectional area of ​​the winding center hole (H1) of the electrode assembly (E) are determined, the flow rate of the air flowing through the winding center hole (H1) can be calculated according to the insertion speed of the electrode assembly (E). By substituting this value into the Bernoulli equation, the pressure (p1) acting inside the battery can (C) when the electrode assembly assembly (EA) is inserted can be calculated. Ultimately, if the pressure (p1) acting inside the battery can (C) when the electrode assembly assembly (EA) is inserted is made to be approximately atmospheric pressure, it can be seen that the pressure acting in the winding center hole (H1) region of the electrode assembly (E) is offset. That is, the air blower (30) can calculate an air pressure capable of offsetting the pressure acting on the winding center hole (H1) region of the electrode assembly (E), and inject air equivalent to the calculated value toward the winding center hole (H1) of the electrode assembly (E). As a result, according to the above configuration, pressure offsetting of the vulnerable part of the separator becomes possible, and thus, the level of reform loosening can be effectively reduced. Accordingly, the battery capacity and lifespan can be improved.

[0104]

[0105] In another aspect of the present invention, the air blower (30) may be configured to inject air so that the difference between the internal pressure (p1) of the battery can (C) and the external pressure (p2) of the battery can (C) is about 5 mbar or less.

[0106] For example, referring to FIG. 10, the inventors of the present invention confirmed that when the diameter of the winding center hole (H1) of the electrode assembly (E) is about 6 mm, and the difference between the pressure (p1) inside the battery can (C) and the pressure (p2) outside the battery can (C) exceeds about 10 mbar, deformation occurs in the separator near the winding center hole (H1). On the other hand, when the difference between the pressure (p1) inside the battery can (C) and the pressure (p2) outside the battery can (C) becomes about 5 mbar through pressure offset by the air blower (30), deformation of the separator near the winding center hole (H1) does not occur.

[0107] Therefore, according to the above-described configuration of the present invention, the difference between the internal pressure (p1) of the battery can (C) and the external pressure (p2) of the battery can (C) can be maintained at a trace value, thereby effectively preventing deformation behavior of the separator.

[0108]

[0109] In another aspect of the present invention, the air blower (30) may be configured to operate after the electrode assembly (EA) is inserted a predetermined length in the longitudinal direction of the battery can (C).

[0110] For example, referring to FIG. 10, the air blower (30) may be configured to operate after the electrode assembly assembly (EA) is inserted about 1 / 3 to 1 / 2 in the longitudinal direction of the battery can (C). In the insertion process of the electrode assembly assembly (EA), since the internal hydraulic pressure is released and affects the core part after the electrode assembly assembly (EA) is inserted about 1 / 3 to 1 / 2 into the battery can (C), it is preferable to perform pressure compensation through operation of the air blower (30) after that point. Meanwhile, the air injection may occur temporarily at the point where the electrode assembly assembly (EA) is inserted about 1 / 3 to 1 / 2 into the battery can (C), or may occur continuously after the point where the electrode assembly assembly (EA) is inserted about 1 / 3 to 1 / 2 into the battery can (C).

[0111]

[0112] In another aspect of the present invention, the air blower (30) may be configured to inject air so that the diameter of the winding center after deformation of the electrode assembly assembly (EA) exceeds about 75% of the diameter of the winding center before deformation of the electrode assembly assembly (EA).

[0113] For example, referring to FIG. 10, in a case where the diameter of the winding center hole (H1) before deformation of the electrode assembly (E) is about 6 mm, if the diameter of the deformed winding center hole (H1) after the insertion process of the electrode assembly (EA) becomes about 4.5 mm or less, it was confirmed that the separator is excessively damaged during the CRW (Cathode Rivet Welding) welding process for welding the terminal and the first current collector (P1), and thus, issues of reduced battery capacity and lifespan occur. Therefore, it is preferable that the diameter of the deformed winding center hole (H1) after the insertion process of the electrode assembly (EA) exceeds about 4.5 mm. That is, it is preferable that the diameter of the winding center after deformation of the electrode assembly assembly (EA) exceeds about 75% of the diameter of the winding center before deformation of the electrode assembly assembly (EA), and the air blower (30) of the present invention can be configured to calculate and inject an amount and / or speed of air such that the diameter of the winding center after deformation of the electrode assembly assembly (EA) exceeds about 75% of the diameter of the winding center before deformation of the electrode assembly assembly (EA).

[0114] More preferably, the air blower (30) may be configured to inject air so that the pressure inside the battery can (C) is lower than a value at which the shape of the winding center of the electrode assembly assembly (EA) is not deformed. For example, referring to Fig. 11, it can be confirmed that the separator located near the deformed winding center hole (H1) after the insertion process of the electrode assembly assembly (EA) is not deformed.

[0115] That is, according to the above-described configuration of the present invention, when the air inside the battery can (C) is discharged during the electrode assembly (E) insertion process, deformation of the separator can be prevented by reducing the pressure through air injection. In addition, by reducing the level of reform loosening, the battery capacity and lifespan can be improved by improving core collision. In addition, damage to the separator of the electrode assembly (E) can be reduced and the process capability can be improved, and further, cost reduction can be achieved.

[0116]

[0117] Meanwhile, although terms indicating directions such as up and down are used in this specification, it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0118] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0119] [Explanation of symbols]

[0120] 1 Insert device

[0121] E electrode assembly

[0122] H1 winding center hole

[0123] C battery can

[0124] C1 opening

[0125] C2 closure

[0126] P1 First House

[0127] P2 Second House

[0128] 10 can holders

[0129] 20 Lower stopper

[0130] 30 Air Blower

[0131] 31 Positive pressure generator

[0132] 32 air piping

Claims

1. An insert device for inserting an electrode assembly including an electrode assembly and a first current collector coupled to one surface of the electrode assembly into a battery can, A can holder for holding the above battery can; A lower stopper configured to support the electrode assembly assembly from below and move in a direction parallel to the central axis of the electrode assembly assembly; and An air blower provided on the lower stopper and configured to inject air in a direction toward the battery can for the electrode assembly assembly. An insert device characterized by including a .

2. In paragraph 1, The above first collector, An insert device characterized in that it is bonded on a surface of the electrode assembly facing the battery can.

3. In paragraph 1, The above first collector, An insert device characterized by having an area smaller than the area of ​​one side of the electrode assembly.

4. In paragraph 1, The above lower stopper, An insert device characterized in that it is configured to insert the electrode assembly into the inside of the battery can.

5. In paragraph 1, The above lower stopper, An insert device characterized in that the electrode assembly assembly positioned lower than the can is pushed upward and the electrode assembly assembly is pushed toward the opening of the battery can.

6. In paragraph 1, The above air blower, An insert device characterized in that it is configured to inject air toward the winding center of the electrode assembly.

7. In paragraph 1, The above air blower, An insert device characterized in that it is configured to inject air in the insertion direction of the electrode assembly.

8. In paragraph 1, The above air blower, An insert device characterized in that it is configured to inject air from downward to upward in a direction parallel to the central axis of the electrode assembly.

9. In paragraph 1, The above air blower, An insert device characterized in that it is configured to offset the pressure acting on the winding center hole area of ​​the electrode assembly.

10. In paragraph 1, The above air blower, An insert device characterized in that air is injected so that the difference between the internal pressure of the battery can and the external pressure of the battery can becomes 5 mbar or less.

11. In paragraph 1, The above air blower, An insert device characterized in that it is configured to operate after the electrode assembly is inserted a predetermined length in the longitudinal direction of the battery can.

12. In paragraph 1, The above air blower, An insert device characterized in that it is configured to operate after the electrode assembly is inserted 1 / 3 in the longitudinal direction of the battery can.

13. In paragraph 1, The above air blower, An insert device characterized in that air is injected so that the diameter of the winding center after deformation of the electrode assembly assembly exceeds 75% of the diameter of the winding center before deformation of the electrode assembly assembly.

14. In paragraph 1, The above air blower, An insert device characterized in that air is injected so that the pressure inside the battery can is lower than a value at which the shape of the winding center of the electrode assembly is not deformed.

Images