Swage apparatus and method for determining error in swage process

Abstract

Disclosed are a swage apparatus capable of preventing scratches from occurring due to excessive pressure applied to an opening of a battery housing during a swage process, and a method for determining an error in the swage process. The swage apparatus according to an embodiment of the present invention is for performing a swage process of compressing an opening of a cylindrical battery housing in which an electrode assembly is accommodated. The swage apparatus comprises: a swage module that includes a housing, a pressing operation unit provided in the housing, and a pressing unit, drives the pressing operation unit between a pressing release position and a pressing position along an operation direction parallel to the central axis of the battery housing, and operates the pressing unit by the pressing operation unit to compress the opening of the battery housing; a load measurement unit that is installed in the housing and measures a load applied by the pressing operation unit from the pressing position toward the operation direction; and a swage process error determination unit determining a swage process error on the basis of a load measurement value applied by the pressing operation unit in the operation direction.

Description

Swaging device and swaging process error determination method

[0001] The present invention relates to a swaging device and a method for determining errors in a swaging process, and more specifically, to a swaging device and a method for determining errors in a swaging process that can prevent scratch defects from occurring when excessive pressure is applied to the opening of a battery housing during a swaging process in which the opening of a battery housing is compressed.

[0002] Secondary batteries are attracting attention as an energy source for improving eco-friendliness and energy efficiency because they have high energy density and the advantage of being able to drastically reduce the use of fossil fuels, as well as the advantage of not generating by-products from energy use. Due to these advantages, secondary batteries are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric power sources.

[0003] When a high output voltage is required, the output voltage can be supplied by a battery pack formed by connecting multiple unit secondary battery cells, i.e., battery cells, in series. Additionally, a battery pack can be configured by connecting multiple battery cells in parallel according to the required charge / discharge capacity of the battery pack. The number of battery cells included in the battery pack can be varied depending on the required output voltage and / or charge / discharge capacity.

[0004] Among battery cells, cylindrical batteries can be manufactured through a swage process in which a cylindrical electrode assembly, in which the positive electrode, negative electrode, and separator are wound in a jelly-roll form, is inserted into a battery housing through an opening, and then assembled by compressing the opening. In the swage equipment used to perform the swage process, excessive pressure may be intermittently applied to the opening of the battery housing due to various causes such as mechanical defects, design errors, or errors in the diameter of the battery housing, which may result in scratch defects on the side of the opening of the cylindrical battery housing.

[0005] If a battery with a scratch defect is detected by the battery appearance inspection equipment positioned downstream of the swaging facility, an error in the swaging process can be identified and subsequent measures taken; however, in this case, thousands of batteries located between the swaging facility and the battery appearance inspection equipment must be discarded, or additional work must be performed to sort out defective batteries. This increases battery sorting time and equipment idle time, thereby reducing productivity and potentially incurring cost losses due to the disposal of batteries. The background technology described above is intended to explain the background of the derivation of the present invention and does not imply that it is technology known prior to the filing of the present invention.

[0006] One objective of the present invention is to provide a swaging device and a method for determining errors in a swaging process that can prevent scratch defects from occurring when excessive pressure is applied to the opening of a battery housing during a swaging process in which the opening of a battery housing is compressed.

[0007] The technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description of the invention below.

[0008] A swaging device according to an embodiment of the present invention is for performing a swaging process that compresses an opening of a cylindrical battery housing in which an electrode assembly is accommodated, and comprises a housing, a pressurizing operating unit and a pressurizing unit provided within the housing, wherein the pressurizing operating unit is driven between a pressurizing release position and a pressurizing position along an operating direction parallel to the central axis of the battery housing, and the pressurizing unit is actuated by the pressurizing operating unit to compress the opening of the battery housing; a load measuring unit installed in the housing and configured to measure a load applied by the pressurizing operating unit in the direction of operation at the pressurizing position; and a swaging process error determining unit that determines a swaging process error based on a load measuring value applied in the direction of operation by the pressurizing operating unit.

[0009] The above-mentioned pressurizing member may include a plurality of jaws arranged to surround the battery housing. The pressurizing operating member may include a collet chuck arranged in a ring shape within the housing to surround the plurality of jaws.

[0010] The plurality of jaws may be configured to press against the center of the battery housing as the collet chuck descends along the inner inclined surface of the housing, thereby compressing the opening of the battery housing.

[0011] The load measuring unit may include one or more load cells disposed at the lower part of the collet chuck within the housing.

[0012] The load cell may be configured to measure the load that the collet chuck applies downward to the load cell during the downward movement of the collet chuck.

[0013] The above swaging process error determination unit may be configured to determine the swaging process error by comparing the load measurement value of the load cell with a set reference load.

[0014] The load measuring unit may include a plurality of load cells. The plurality of load cells may be spaced apart and arranged along the circumferential direction of the housing.

[0015] The above swaging process error determination unit may be configured to analyze the swaging process error and the cause of the error based on a plurality of load measurement values ​​obtained by the plurality of load cells.

[0016] The plurality of load cells may include three load cells arranged at 120° intervals. The swaging process error determination unit may be configured to determine at least one swaging process error among the outer diameter dimension defect, elliptical defect, and mechanical part warping error of the battery housing based on the result of comparison between the plurality of load measurements and the reference load and the deviation between the plurality of load measurements.

[0017] The above swaging process error determination unit may be configured to determine a swaging process error corresponding to an outer diameter dimension defect of the battery housing when all of the plurality of load measurements exceed the reference load; determine a swaging process error corresponding to an elliptical defect when the plurality of load measurements correspond to a load pattern set in relation to an elliptical defect of the battery housing; and determine a swaging process error corresponding to a mechanism distortion when at least one of the plurality of load measurements exceeds the reference load and the maximum deviation between the plurality of load measurements exceeds the reference deviation.

[0018] The above housing may be provided with an outlet hole through which wiring is drawn to transmit the load measurement value obtained by the load cell to the swaging process error determination unit.

[0019] The above swaging process error determination unit may be configured to stop the operation of the swaging module and generate an alarm notifying the swaging process error when it determines the above swaging process error.

[0020] A method for determining an error in a swaging process according to an embodiment of the present invention is a method for determining an error in a swaging process that compresses an opening of a cylindrical battery housing in which an electrode assembly is accommodated, comprising: a step of performing a swaging process by driving a pressurizing operating unit between a pressurizing release position and a pressurizing position along an operating direction parallel to the central axis of the battery housing by means of a swaging module including a housing and a pressurizing operating unit and a pressurizing unit provided within the housing, and by operating the pressurizing unit by means of the pressurizing operating unit to compress the opening of the battery housing; a step of measuring a load applied by the pressurizing operating unit in the direction of operation at the pressurizing position by means of a load measuring unit installed in the housing; and a step of determining a swaging process error based on a load measurement value applied by the pressurizing operating unit in the direction of operation by means of a swaging process error determination unit.

[0021] The step of measuring the load may include the step of measuring the load that the collet chuck applies downward to the load cell by the load cell during the downward movement of the collet chuck.

[0022] The step of determining the above swaging process error may include a step of determining the above swaging process error by comparing the load measurement value of the load cell with a set reference load.

[0023] The step of determining the above swaging process error may include a step of analyzing the swaging process error and the cause of the error based on a plurality of load measurement values ​​obtained by the plurality of load cells.

[0024] The step of determining the above swaging process error may include determining at least one swaging process error among the outer diameter dimension defect, elliptical defect, and mechanical part warping error of the battery housing based on the result of comparison between the plurality of load measurements and the reference load and the deviation between the plurality of load measurements.

[0025] According to an embodiment of the present invention, a swaging device and a method for determining an error in a swaging process are provided, which can prevent scratch defects from occurring when excessive pressure is applied to an opening of a battery housing during a swaging process in which an opening of a battery housing is compressed.

[0026] The effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by a person skilled in the art from the description of the invention below.

[0027] FIG. 1 is a perspective view showing a swage device according to an embodiment of the present invention.

[0028] FIG. 2 is a cross-sectional view showing a swage device according to an embodiment of the present invention.

[0029] FIG. 3 is a plan view showing a swaging device of a swaging device according to an embodiment of the present invention.

[0030] FIG. 4 is a partial cross-sectional enlarged view of a swage device according to an embodiment of the present invention, and is a cross-sectional view showing an enlarged view of section 'A' of FIG. 2.

[0031] FIG. 5 is a partially cutaway perspective view showing a swage device according to an embodiment of the present invention.

[0032] FIG. 6 is a cross-sectional view showing the state in which a pressurizing operating part constituting a swage device according to an embodiment of the present invention is raised to a pressurized release position.

[0033] FIG. 7 is a plan view showing the state in which a pressurizing operating part constituting a swage device according to an embodiment of the present invention is raised to a pressurized release position.

[0034] FIG. 8 is a cross-sectional view showing the state in which a pressurizing operating part constituting a swage device according to an embodiment of the present invention has been lowered to a pressurized position.

[0035] FIG. 9 is a plan view showing the state in which a pressurizing operating part constituting a swage device according to an embodiment of the present invention has been lowered to a pressurized position.

[0036] Figure 10 is a cross-sectional view showing the battery housing before the swaging process is performed.

[0037] FIG. 11 is a cross-sectional view showing a battery housing with the opening compressed by the swaging process.

[0038] FIG. 12 is a perspective view showing a battery cell manufactured by being assembled by a swaging device according to one embodiment of the present invention.

[0039] FIG. 13 is a cross-sectional perspective view of a battery cell according to FIG. 12.

[0040] FIG. 14 is a cross-sectional view of a battery cell according to FIG. 12.

[0041] FIG. 15 is a flowchart illustrating an error determination method for a swaging process according to an embodiment of the present invention.

[0042] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques are not specifically described to avoid the present invention being interpreted ambiguously. Throughout the specification, like reference numerals refer to like components.

[0043] A swaging device according to an embodiment of the present invention installs a load measuring unit (e.g., a load cell) in the housing of a swaging module, measures the load applied by the load measuring unit in the direction of operation to compress the opening of the battery housing at the pressurized position of the pressurizing operating unit, and determines a swaging process error based on the load measurement value applied by the pressurizing operating unit in the direction of operation. Accordingly, it is possible to prevent scratch defects from occurring due to excessive pressure being applied to the opening of the battery housing during the swaging process of compressing the opening of the battery housing.

[0044] FIG. 1 is a perspective view showing a swage device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a swage device according to an embodiment of the present invention. FIG. 3 is a plan view showing a swage device according to an embodiment of the present invention. FIG. 4 is a partial cross-sectional enlarged view of a swage device according to an embodiment of the present invention, showing an enlarged view of section 'A' of FIG. 2. FIG. 5 is a partial cutaway perspective view showing a swage device according to an embodiment of the present invention.

[0045] Referring to FIGS. 1 to 5, a swaging device (100) according to an embodiment of the present invention is configured to perform a swaging process that compresses an opening (20b) of a cylindrical battery housing (20) in which an electrode assembly is received, and may include a swaging module (200), a load measuring unit (300), and a swaging process error determining unit (400). In one embodiment, the swaging device (100) may be provided in a rotary type in multiple units depending on the production speed of the assembly process, and may be provided to compress the opening of the battery housing by the pressure of a set cylinder after the battery housing is inserted while the swaging equipment rotates. The swaging device (100) is not limited to the illustrated rotary structure and may be implemented in various forms.

[0046] FIGS. 1 to 5 illustrate a single swage module (200) constituting a swage device (100). When the swage device (100) is configured to include a plurality of swage modules (200), the swage device (100) according to an embodiment of the present invention may have a load measuring unit (300) provided in at least one swage module (200) among the plurality of swage modules (200). The swage process error judgment unit (400) may be provided individually for each of the plurality of swage modules (200) to determine errors in the swage process, or it may be configured to determine errors in the swage process in parallel or sequentially for two or more swage modules (200).

[0047] The swage module (200) may include a housing (210) and a pressurizing operating part (220) and a pressurizing part (230) provided within the housing (210). The housing (210) may be provided to accommodate the pressurizing operating part (220) and the pressurizing part (230). That is, the pressurizing operating part (220) and the pressurizing part (230) may be accommodated in an internal space provided in the housing (210). The housing (210) may be provided with an outlet hole (213) on its outer surface so that wiring for transmitting a load measurement value obtained by the load measuring part (300) to the swage process error determination part (400) can be drawn out. A support groove (215) for supporting the battery housing (20) may be provided in the central region of the housing (210).

[0048] In one embodiment, the pressurizing part (230) may include a plurality of jaws (231, 232, 233) arranged to surround the battery housing (20). The plurality of jaws (231, 232, 233) may be designed to have an inner diameter corresponding to the outer diameter of the opening of the battery housing (20) after the swaging process, when pressed toward the center. The pressurizing operating part (220) may include a collet chuck (221, 222, 223) arranged in a ring shape to surround the plurality of jaws (231, 232, 233) within the housing (210). A plurality of collet chucks (221, 222, 223) can be designed to have an inner diameter corresponding to the outer diameter of a plurality of jaws (231, 232, 233) while the plurality of jaws (231, 232, 233) are pressed towards the center.

[0049] A plurality of jaws (231, 232, 233) may be configured to press against the center of the battery housing (20) and compress the opening (20b) of the battery housing (20) as the collet chuck (221, 222, 223) descends along the inner inclined surface of the housing (210) which is wider at the top and narrower at the bottom (funnel shape). The swage module (200) may be equipped with a driving device (240) for driving the pressurizing actuator (220) in the operating direction (in the illustrated example, the third direction, Z, which is the up-down direction). The driving device (240) may be designed with various driving mechanisms such as a driving cylinder or a driving motor.

[0050] FIG. 6 is a cross-sectional view showing a state in which a pressurizing actuator constituting a swaging device according to an embodiment of the present invention is raised to a pressurized release position. FIG. 7 is a plan view showing a state in which a pressurizing actuator constituting a swaging device according to an embodiment of the present invention is raised to a pressurized release position. FIG. 8 is a cross-sectional view showing a state in which a pressurizing actuator constituting a swaging device according to an embodiment of the present invention is lowered to a pressurized position. FIG. 9 is a plan view showing a state in which a pressurizing actuator constituting a swaging device according to an embodiment of the present invention is lowered to a pressurized position. FIG. 10 is a cross-sectional view showing a battery housing before the swaging process is performed. FIG. 11 is a cross-sectional view showing a battery housing in a state where the opening is compressed by the swaging process.

[0051] Referring to FIGS. 1 through 11, the swage module (200) can drive the pressure operating part (220) between a pressure release position and a pressure position along an operating direction (third direction, Z) parallel to the central axis of the battery housing (20). In the illustrated embodiment, the pressure position is a position set so that the pressure operating part (220) presses the pressure part (230) to compress the opening (20b) of the battery housing (20), and the pressure release position may be a position set so that the pressure operating part (220) does not press the pressure part (230). The pressure release position may be a position above the pressure position.

[0052] The swaging module (200) can operate the pressurizing unit (230) by means of the pressurizing operating unit (220) to compress the opening of the battery housing (20). As the pressurizing operating unit (220) descends from the pressurizing release position to the pressurizing position, the pressurizing unit (230) pressurizes the opening (20b) of the battery housing (20), and as the pressurizing unit (230) compresses the opening (20b) of the battery housing (20), a swaging process can be performed. Below, a cylindrical secondary battery (battery cell) will be described first, and then the swaging device (100) will be described.

[0053] FIG. 12 is a perspective view showing a battery cell manufactured by being assembled by a swaging device according to an embodiment of the present invention. FIG. 13 is a cross-sectional perspective view of the battery cell according to FIG. 12. FIG. 14 is a cross-sectional view of the battery cell according to FIG. 12. For convenience of explanation, in this specification, the direction following the longitudinal direction of the winding axis of an electrode assembly wound in a jelly roll shape is referred to as the "axial direction," "up-down direction," or "height direction." The direction surrounding the winding axis is referred to as the "circumferential direction" or "peripheral direction." The direction approaching the winding axis or moving away from the winding axis is referred to as the "radial direction." Among the radial directions, the direction approaching the winding axis may be referred to as the "centripetal direction," and the direction moving away from the winding axis may be referred to as the "centrifugal direction."

[0054] The battery cell (1) may include an electrode assembly (10), a battery housing (20), a first current collector (30), a battery cap (40), a sealing gasket (50), a second current collector (60), a rivet (70), and an insulating part (80). The battery cell including the electrode assembly (10) is not limited to the shape of the battery cell (1) shown in FIGS. 12 to 14 and can be applied to batteries of other shapes. The battery cell (1) may be a cylindrical secondary battery (cylindrical battery cell).

[0055] The electrode assembly (10) may be provided in a cylindrical shape having a core and an outer surface, wherein a first electrode (e.g., a negative electrode), a second electrode (e.g., a positive electrode), and a separator interposed between these electrodes are wound around a winding axis. The electrode assembly (10) may be a jelly-roll type electrode assembly. An additional separator may be provided on the outer surface of the electrode assembly (10) for insulation from the battery housing (20). The electrode assembly (10) may be provided without limitation to have a winding structure well known in the art of the present invention.

[0056] The first electrode of the electrode assembly (10) may include a first electrode current collector and a first electrode active material applied on one or both sides of the first electrode current collector. At one end (upper end) in the width direction (a direction parallel to the height direction of the battery cell) of the first electrode, there may be a non-coated portion where the first electrode active material is not applied. That is, the first electrode may include a first non-coated portion (11) that is not coated with active material at one long end along the winding direction and is exposed to the outside of the separator. The first non-coated portion (11) may be provided at the upper end with respect to the height direction of the electrode assembly (10) housed within the battery housing (20). At least a portion of the first non-coated portion (11) may be used as an electrode tab itself. The first non-coated portion (11) may be, for example, a negative electrode tab.

[0057] The second electrode of the electrode assembly (10) may include a second electrode current collector and a second electrode active material applied on one or both sides of the second electrode current collector. Based on the width direction (height direction) of the second electrode, a non-coated portion where the second electrode active material is not applied may exist at the other end. That is, the second electrode may include a second non-coated portion (12) that is not coated with active material at the other long end along the winding direction and is exposed to the outside of the separator. The second non-coated portion (12) may be provided at the bottom based on the height direction of the electrode assembly (10) housed within the battery housing (20). At least a portion of the second non-coated portion (12) may be used as an electrode tab itself. The second non-coated portion (12) may be, for example, a positive electrode tab.

[0058] The battery housing (20) may be a roughly cylindrical receptacle with an opening formed on one side. The battery housing (20) may be provided with a conductive metal material. The battery housing (20) may be configured to accommodate the electrode assembly (10) of the secondary battery. The side of the battery housing (20) and the lower surface located opposite the opening (20a) may be formed integrally. The battery housing (20) may be configured to accommodate the electrode assembly (10) and the electrolyte through the opening (20a) formed on its upper side.

[0059] The battery housing (20) may have a beading portion (21) formed in an end region adjacent to an opening (20a) provided at the top thereof, and a crimping portion (22) formed on the beading portion (21). The beading portion (21) has a shape in which the outer circumference of the battery housing (20) is pressed in to a predetermined depth. The beading portion (21) may have a shape in which it is pressed inward in the region between the opening (20a) of the battery housing (20) and the internal receiving space that accommodates the electrode assembly (10).

[0060] The beading portion (21) provides a support surface on which a sealing gasket (50) and a battery cap (40) can be seated. Additionally, the beading portion (21) may provide a support surface on which at least a portion of the edge perimeter of the first current collector (30) can be seated and joined. At least a portion of the edge perimeter of the current collector (30), at least a portion of the edge perimeter of the sealing gasket (50), and at least a portion of the edge perimeter of the battery cap (40) can be seated on the upper surface of the beading portion (21). The beading portion (21) can be formed by pressing the outer circumference of the battery housing (20) inward in an area adjacent to the opening (20a) of the battery housing (20) while the electrode assembly (10) is received within the battery housing (20) through the opening (20a).

[0061] In order to stably support the first current collector (30), the battery cap (40), and the sealing gasket (50), the upper surface of the beading portion (21) may have a shape that extends along a direction approximately parallel to the lower surface of the battery housing (20), that is, a shape that extends in a direction approximately perpendicular to the side wall of the battery housing (20). The beading portion (21) can function as a support portion on which the battery cap (40), etc., is seated, while preventing the electrode assembly (10), which has a size corresponding to the inner diameter of the internal receiving space of the battery housing (20), from coming out through the opening (20a) formed at the top of the battery housing (20).

[0062] The crimping portion (22) extends upward from the beading portion (21) and is formed on the upper part of the beading portion (21). The crimping portion (22) has a bent shape that extends to wrap around the edge perimeter and part of the upper surface of the battery cap (40) placed on the upper part of the beading portion (21). The battery cap (40) is fixed on the beading portion (21) by the crimping portion (22). The crimping portion (22) may have a shape that extends inwardly from the upper perimeter of the battery housing (20) in the radial direction (centripetal direction) of the battery cell (1). The crimping portion (22) is provided in an area corresponding to the edge perimeter of the upper surface of the battery cap (40) to fix the battery cap (40) and prevent the battery cap (40) from moving upward.

[0063] The upper portion of the crimping portion (22) is formed by bending so that it extends inward by a predetermined distance along the radial direction of the battery cell (1) to wrap around a part of the upper surface of the battery cap (40), thereby securing the perimeter of the upper surface of the battery cap (40). The perimeter area of ​​the battery cap (40) is interposed between the upper portion of the crimping portion (22) and the beading portion (21) and is secured to the battery housing (20), covering the opening (20a) of the battery housing (20).

[0064] The first current collector (30) is housed inside the battery housing (20). The first current collector (30) is made of a conductive metal material and can be electrically connected to the electrode assembly (10). The first current collector (30) can be electrically connected to the battery housing (20). That is, the current collector (30) can electrically connect the first electrode of the electrode assembly (10) and the battery housing (20). The first current collector (30) may have a support portion (31), a tab coupling portion (32), and a housing coupling portion (33).

[0065] The support portion (31) and the tab connecting portion (32) of the first current collector (30) are positioned on the upper part of the electrode assembly (10). The support portion (31) is positioned on one side of the electrode assembly (10). The tab connecting portion (32) extends from the support portion (31) and is connected to the first non-reinforcing portion (11) of the electrode assembly (10). The tab connecting portion (32) can be connected to the electrode assembly (10), for example, by welding a certain area while seated on the first non-reinforcing portion (11) of the electrode assembly (10). The tab connecting portion (32) of the first current collector (30) may be located below the lower surface of the beading portion (21).

[0066] A through hole (not shown) may be formed in the first current collector (30) to allow flames generated inside the battery cell (1) to escape smoothly. Accordingly, even if a thermal runaway phenomenon occurs on the side of the electrode assembly (10), the flames and venting gas generated from the electrode assembly (10) can be smoothly discharged through the through hole without being blocked by the first current collector (30) located on the upper side of the electrode assembly (10). Therefore, it is possible to prevent the flames from moving toward the beading part (21) located in the vicinity of the electrode assembly (10) and the first current collector (30) and causing pinholes in the beading part (21), and to prevent the fire from spreading to other battery cells (1) located around the battery cell (1) where the fire occurred.

[0067] The support member (31) may be provided with a current collector hole (H2) formed at a position corresponding to a winding hole (H1) formed approximately in the center of the electrode assembly (10). The winding hole (H1) and the current collector hole (H2), which are in communication with each other, do not need to function as a passage for a welding rod or laser beam for welding between the electrode terminal of the electrode assembly (10) and the current collector, or between the electrode terminal and a lead tab (not shown). Therefore, the energy density of the electrode assembly (10) can be increased by reducing the size of the winding hole (H1) and the current collector hole (H2). If the diameter of the current collector hole (H2) is excessively smaller than the diameter of the winding hole (H1), the hole formed in the winding hole (H1) may be obscured, which may reduce liquid injection performance. Accordingly, so that the current collector hole (H2) does not obstruct the winding hole (H1) formed in the core of the electrode assembly (10), the winding hole (H1) of the electrode assembly (10) may have a diameter substantially the same as or larger than that of the current collector hole (H2).

[0068] The housing coupling portion (33) extends from the support portion (31) to a periphery area and is coupled to the inner surface of the battery housing (20). The housing coupling portion (33) may extend from the support portion (31) and be electrically coupled to the inner surface of the battery housing (20). For example, the housing coupling portion (33) may be coupled to the upper surface of the beading portion (21) on the inner surface of the battery housing (20).

[0069] The inner diameter of the battery housing (20) in the area where the beading portion (21) is formed may be smaller than the diameter of the electrode assembly (10). For stable contact and connection, the beading portion (21) may have a shape that extends along a direction approximately parallel to the lower surface of the battery housing (20), that is, a direction approximately perpendicular to the side wall of the battery housing (20). The housing connection portion (33) may be welded to the upper surface of the beading portion (21). For welding the connection between the battery housing (20) and the first current collector (30), for example, laser welding, ultrasonic welding, or spot welding may be applied.

[0070] A battery cap (40) is provided to cover an opening (20a) of a battery housing (20). The battery cap (40) may be coupled to the battery housing (20) to seal the opening (20a) of the battery housing (20) through a crimping process via a sealing gasket (50). The battery cap (40) may be provided with a venting portion (41) formed to prevent an increase in internal pressure caused by gas generated inside the battery housing (20).

[0071] The venting portion (41) may be configured to break when the internal pressure of the battery housing (20) increases above a certain level. The venting portion (41) is formed in a part of the battery cap (40) and may be a structurally weaker area than the surrounding area so that it can easily break when pressure is applied to the inside due to thermal runaway, etc. For example, the venting portion (41) may be an area having a thinner thickness compared to the surrounding area. The venting portion (41) may be formed as a roughly circular closed loop.

[0072] The battery cap (40) covers an opening (20a) formed on one side of the battery housing (20). The battery cap (40) can be secured by a crimping portion (22) formed on the top of the battery housing (20). To improve the fixing force and the sealing performance of the battery housing (20), a sealing gasket (50) is interposed between the battery housing (20) and the battery cap (40), and between the current collector (30) and the battery cap (40). The sealing gasket (50) can seal the top opening of the battery housing (20) between the battery cap (40) and the crimping portion (22) of the battery housing (20), and electrically insulate the battery housing (20) from the battery cap (40). The sealing gasket (50) may include a material having insulating and elastic properties. The sealing gasket (50) may include, for example, a polymer resin.

[0073] Accordingly, the current collector (30) may be interposed between the beading portion (21) of the battery housing (20) and the sealing gasket (50). The current collector (30) interposed between the beading portion (21) and the sealing gasket (50) may be secured by the bending of the crimping portion (22) extending upward from the beading portion (21). The sealing gasket (50) is provided to surround the battery cap (40) to seal the space between the battery cap (40) and the battery housing (20). The sealing gasket (50) serves to maintain airtightness between the battery housing (20) and the battery cap (40). A rivet (70) is inserted into and joined to an opening formed in the bottom portion of the battery housing (20). An insulating portion (80) may be interposed between the rivet (70) and the opening of the battery housing (20). The insulating part (80) can insulate the rivet (70) from the battery housing (20).

[0074] Referring again to FIGS. 1 to 11, for the manufacture of the battery cell (1) described above, a swaging process is performed in which an electrode assembly (10) is inserted into a battery housing (20) and the opening (20b) of the battery housing (20) is compressed to assemble it. If excessive scratches occur in the opening (20b) of the battery housing (20) during the swaging process, it may adversely affect the assembly performance of the battery. Below, a load measuring unit (300) and a swaging process error judgment unit (400) are described to effectively prevent scratch defects from occurring when excessive pressure is applied to the opening (20b) of the battery housing (20) during the swaging process.

[0075] A load measuring unit (300) may be installed in the housing (210) of the swage module (200). The load measuring unit (300) may be installed to measure the load applied by the pressurizing operating unit (220) in the third direction (Z), which is the direction of operation, when the pressurizing operating unit (220) is in the pressurized position. The load measuring unit (300) may include one or more load cells (310, 320, 330). The load cells (310, 320, 330) may be placed below the pressurizing operating unit (220) within the housing (210) to measure the load (pressure) applied in the third direction (Z), which is the direction of operation, when the pressurizing operating unit (220) is in the pressurized position.

[0076] A plurality of load cells (310, 320, 330) may be disposed below the corresponding collet chuck (221, 222, 223). The load cells (310, 320, 330) can measure the load applied downward by the corresponding collet chuck (221, 222, 223) to the load cells (310, 320, 330) during the downward movement of the collet chuck (221, 222, 223), i.e., the pressure applied in the third direction (Z). The load measuring unit (300) may include a plurality of load cells (310, 320, 330). The plurality of load cells (310, 320, 330) may be spaced apart and arranged along the circumferential direction of the housing (210).

[0077] In the illustrated embodiment, the load measuring unit (300) includes three load cells (310, 320, 330) arranged at 120° intervals, but the number and arrangement of the load cells (310, 320, 330) can be varied. In a preferred embodiment, the load cells (310, 320, 330) may be provided in the same number as the collet chucks (221, 222, 223). Each load cell (310, 320, 330) may be installed to be positioned in the center area of ​​the corresponding collet chuck (221, 222, 223) with respect to the circumferential direction.

[0078] The swaging process error determination unit (400) can determine a swaging process error based on a load measurement value applied in the operating direction (third direction, Z) by the pressurizing operating unit (220). The swaging process error determination unit (400) can determine a swaging process error by comparing the load measurement value of the load cell (310, 320, 330) with a set reference load (or reference load range).

[0079] When the collet chucks (221, 222, 223) of the pressurizing operating unit (220) descend to a pre-designated target pressurizing position and pressurize the pressurizing unit (230) with an appropriate force, the load applied by the pressurizing operating unit (220) to the load measuring unit (300) in the operating direction falls within the reference load range. In contrast, if the collet chuck (221, 222, 223) of the pressurizing operating unit (220) pressurizes the pressurizing unit (230) at a position that deviates from the pre-designed target pressurizing position, the load applied by the pressurizing operating unit (220) to the load measuring unit (300) in the operating direction falls short of or exceeds the reference load range, and in this case, the swaging process error determination unit (400) can determine that an excessive force is being applied to the opening (20b) of the battery housing (20) during the swaging process (when the load measurement value of the load measuring unit exceeds the reference load), or that a weak force is being applied (when the load measurement value of the load measuring unit falls short of the reference load).

[0080] In an embodiment of the present invention, the swaging process error determination unit (400) may analyze not only whether a swaging process error has occurred but also the cause of the swaging process error based on a plurality of load measurement values ​​obtained by a plurality of load cells (310, 320, 330). The swaging process error determination unit (400) may determine swaging process errors, such as defects in the outer diameter dimension, defects in the elliptical shape, and / or errors in the mechanism part distortion of the battery housing (20), based on the result of comparison between a plurality of load measurement values ​​obtained by the load measurement unit (300) and a set reference load (reference load range) and deviations between the plurality of load measurement values.

[0081] In one embodiment, the swaging process error determination unit (400) can determine a swaging process error corresponding to an outer diameter dimension defect of the battery housing (20) when all of the multiple load measurement values ​​obtained by the multiple load cells (310, 320, 330) exceed a reference load. The swaging process error determination unit (400) can determine a swaging process error corresponding to an elliptical defect when the multiple load measurement values ​​obtained by the multiple load cells (310, 320, 330) correspond to a load pattern set in relation to an elliptical defect of the battery housing (20).

[0082] The swaging process error determination unit (400) can determine a swaging process error corresponding to mechanical misalignment when at least one of the multiple load measurement values ​​obtained by multiple load cells (310, 320, 330) exceeds a reference load and the maximum deviation between the multiple load measurement values ​​exceeds a reference deviation. When the swaging process error determination unit (400) determines a swaging process error, it can stop the operation of the swaging module (200) and generate an alarm indicating the swaging process error and the cause of the swaging process error. The swaging process error alarm can be performed in various ways, such as sound, warning sound, message, or display screen output.

[0083] In order to accurately determine errors in the swaging process, it is necessary to install a load measuring unit (300) to accurately measure the load (pressure) applied by the pressurizing operating unit (230) in the operating direction (third direction, Z). The swaging device according to an embodiment of the present invention may be provided with a plurality of load cell mounting grooves (214) arranged along the circumferential direction within the housing (210) so that the load applied by the pressurizing operating unit (230) in the third direction (Z), which is the up-and-down direction, can be measured with high accuracy.

[0084] A support shaft (313) may be installed in the third direction (Z) on the bottom surface of each load cell mounting groove (214) to support the load cell (313) in the vertical direction. The support shaft (313) may be inserted through the mounting groove (314) and mounted on the housing (210). Accordingly, the load cells (310, 320, 330) can accurately measure the vertical pressure applied in the third direction (Z), thereby allowing for accurate determination of errors in the swaging process.

[0085] In order for each collet chuck (221, 222, 223) of the pressure operating unit (220) to transmit a load in the vertical direction to each load cell (310, 320, 330), a stepped groove (220a) may be formed in the corner portion between the bottom surface and the outer surface of each collet chuck (221, 222, 223). When the collet chuck (221, 222, 223) of the pressure operating unit (220) descends, the stepped groove (220a) of the collet chuck (221, 222, 223) presses the upper surface (312) of the corresponding load cell (310, 320, 330) to apply a load in the third direction (Z). Each collet chuck (221, 222, 223) can be lowered to a specified position relative to the load cell (310, 320, 330) by means of a plurality of stepped grooves (220a) provided along the circumferential direction of the pressurized operating part (220), and accordingly, load error caused by misalignment of the position of the collet chucks (221, 222, 223) can be reduced.

[0086] FIG. 15 is a flowchart illustrating an error determination method for a swaging process according to an embodiment of the present invention. A method for determining an error in a swaging process according to an embodiment of the present invention is a method for determining an error in a swaging process in which an opening (20b) of a cylindrical battery housing (20) in which an electrode assembly (10) is accommodated is compressed, comprising the step (S100) of performing a swaging process by means of a swaging module (200) including a housing (210), a pressure operating part (220) provided within the housing (210), and a pressure part (230), by driving the pressure operating part (220) between a pressure release position and a pressure position along an operating direction parallel to the central axis of the battery housing (20), and by operating the pressure part (230) by means of the pressure operating part (220) to compress the opening (20b) of the battery housing (20); and the step (S200) of measuring the load applied by the pressure operating part (220) in the operating direction at the pressure position by means of a load measuring part (300) installed in the housing (210). And it may include a step (S300) of determining a swaging process error based on a load measurement value applied in the operating direction by the pressurizing operating unit (220) by the swaging process error determination unit (400).

[0087] According to the swaging device and swaging process error determination method according to the embodiment of the present invention as described above, it is possible to prevent the occurrence of products with scratch defects on the side of the opening of a cylindrical battery housing by identifying in advance when excessive pressure is applied to the opening of the battery housing due to causes such as mechanical defects of the swaging equipment, design errors of the mechanism, or diameter errors of the battery housing during the swaging process. Therefore, by identifying swaging process errors before thousands of defective batteries are manufactured and taking early follow-up measures, it is possible to reduce the disposal costs and sorting time of defective batteries, decrease equipment idle time, and increase battery productivity.

[0088] Although the present invention has been described above by 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 spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

Claims

1. A swaging device for performing a swaging process that compresses the opening of a cylindrical battery housing containing an electrode assembly, A swage module comprising a housing and a pressurizing actuator and a pressurizing member provided within the housing, wherein the pressurizing actuator is driven between a pressurizing release position and a pressurizing position along an operating direction parallel to the central axis of the battery housing, and the pressurizing member is actuated by the pressurizing actuator to compress an opening of the battery housing; A load measuring unit installed in the above housing and configured to measure the load applied by the above pressurizing actuator in the direction of operation at the pressurizing position; and A swaging process error determination unit configured to determine a swaging process error based on a load measurement value applied in the operating direction by the above-mentioned pressurizing operating unit; A swage device including 2. In Claim 1, The above-mentioned pressurizing member includes a plurality of jaws arranged to surround the battery housing, and A swage device comprising a pressurizing actuator that includes a collet chuck arranged in a ring shape within the housing and surrounding a plurality of jaws.

3. In Claim 2, The above multiple encounters The above collet chuck is configured to press against the center of the battery housing as it descends along the inner inclined surface of the housing, thereby compressing the opening of the battery housing. Swage device.

4. In Claim 2, The load measuring unit comprises one or more load cells disposed at the lower part of the collet chuck within the housing, Swage device.

5. In Claim 4, The load cell is configured to measure the load that the collet chuck applies downward to the load cell during the downward movement of the collet chuck. Swage device.

6. In Claim 5, The above swaging process error determination unit Determining the swaging process error by comparing the load measurement value of the above load cell with a set reference load, Swage device.

7. In Claim 6, The above load measuring unit includes a plurality of the load cells, and A plurality of load cells are spaced apart and arranged along the circumferential direction of the housing, and The above swaging process error determination unit Based on multiple load measurement values ​​obtained by the multiple load cells, analyzing the swaging process error and the cause of the error, Swage device.

8. In Claim 7, The plurality of load cells includes three load cells arranged at 120° intervals, and The above swaging process error determination unit A configuration for determining at least one swaging process error among the outer diameter dimension defect, elliptical defect, and mechanical part warping error of the battery housing based on the result of comparison between the plurality of load measurements and the reference load and the deviation between the plurality of load measurements. Swage device.

9. In Claim 8, The above swaging process error determination unit If all of the above multiple load measurement values ​​exceed the above reference load, a swaging process error corresponding to a defect in the outer diameter dimension of the battery housing is determined; If the above plurality of load measurement values ​​correspond to a load pattern set in relation to the elliptical defect of the battery housing, a swage process error corresponding to the elliptical defect is determined; A method configured to determine a swage process error corresponding to mechanical misalignment when at least one of the plurality of load measurements exceeds the reference load and the maximum deviation between the plurality of load measurements exceeds the reference deviation. Swage device.

10. In Claim 4, The above housing is provided with an outlet hole through which wiring is drawn out to transmit a load measurement value obtained by the load cell to the swaging process error determination unit. Swage device.

11. In Claim 1, The above swaging process error determination unit When the above swaging process error is determined, the swaging module is configured to stop operation and generate an alarm notifying the swaging process error. Swage device.

12. A method for determining an error in a swaging process for determining an error in a swaging process that compresses an opening of a cylindrical battery housing containing an electrode assembly, wherein A step of performing a swaging process by means of a swaging module comprising a housing and a pressurizing actuator and a pressurizing member provided within the housing, wherein the pressurizing actuator is driven between a pressurizing release position and a pressurizing position along an operating direction parallel to the central axis of the battery housing, and the pressurizing member is actuated by the pressurizing actuator to compress an opening of the battery housing; A step of measuring the load applied by the pressurizing actuator in the pressurizing position toward the operating direction by means of a load measuring unit installed in the housing; and A step of determining a swaging process error based on a load measurement value applied in the operating direction by the pressurizing operating unit by the swaging process error determination unit; A method for determining errors in a swaging process including 13. In Claim 12, The above-mentioned pressurizing member includes a plurality of jaws arranged to surround the battery housing, and The above-mentioned pressurizing actuator includes a collet chuck arranged in a ring shape within the housing to surround the plurality of jaws, and The load measuring unit comprises one or more load cells disposed at the lower part of the collet chuck within the housing, and The step of measuring the above load is The method includes the step of measuring the load applied downward by the collet chuck to the load cell during the downward movement of the collet chuck by the load cell. The step of determining the above swaging process error A step comprising determining the swaging process error by comparing the load measurement value of the load cell with a set reference load, Error determination method for the swaging process.

14. In Claim 13, The above load measuring unit includes a plurality of the load cells, and A plurality of load cells are spaced apart and arranged along the circumferential direction of the housing, and The step of determining the above swaging process error A method comprising the step of analyzing the swaging process error and the cause of the error based on a plurality of load measurement values ​​obtained by the plurality of load cells. Error determination method for the swaging process.

15. In Claim 14, The step of determining the above swaging process error A step comprising determining at least one swage process error among the outer diameter dimension defect, elliptical defect, and mechanical part warping error of the battery housing based on the result of comparison between the plurality of load measurements and the reference load and the deviation between the plurality of load measurements. Error determination method for the swaging process.

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