Apparatus for processing electrode tab

Abstract

An apparatus for processing an electrode tab by laser-cutting or notching an uncoated portion of an electrode is provided. The apparatus for processing an electrode tab comprises: a suction unit that draws in gas in a vicinity of a tab processing area in a first direction corresponding to a width direction of a traveling electrode; a first jig having a first guide surface contacting the electrode to guide the travel of the electrode; and a second jig disposed on a side of the first jig in the first direction, defining the tab processing area, and having a second guide surface contacting the uncoated portion to guide the travel of the uncoated portion such that the uncoated portion passes through the tab processing area. A thickness-reduced surface, in which the thickness of the first jig is reduced, is formed at an end portion in the first direction of a first opposite surface of the first guide surface of the first jig.

Description

Electrode tap processing device

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0190522 filed on December 18, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0002] The present invention relates to a tap processing device for an electrode, and more specifically, to a device for processing a tap by cutting or notching the untapped portion of an electrode with a laser.

[0003] A secondary battery is manufactured in a form in which an electrode assembly is embedded in a case, and leads or terminals electrically connected to the electrodes of the electrode assembly are exposed to the outside of the case. The case may be composed of a metal can, a resin housing, or a pouch. The electrode assembly may be manufactured in a structure such as a cylindrical jelly-roll, a folding jelly-roll, or a stack type, corresponding to the shape of the case. Furthermore, to electrically connect the electrodes constituting the electrode assembly to the leads or terminals, tabs are typically provided on the electrodes.

[0004] The above electrode is manufactured by coating an active material onto the surface of a current collector. The above tab is provided by attaching a separate tab member to a bare portion where the surface of the current collector is exposed to the outside of the active material because the active material is not coated on the current collector, or by providing the bare portion as a tab. When providing the bare portion as a tab, the exposed portion of the current collector is cut or notched so that the bare portion is suitable for the function of a tab.

[0005] The metal foil constituting the above-mentioned current collector is processed into a predetermined tap shape by applying external force with a cutting knife or cutting jig or by irradiating a laser to the cutting or notching area. When processing the tap with a laser, a suction airflow is generated in the tap processing area, which is the space where laser notching is performed, in order to prevent fumes or spatter generated during the laser notching process from contaminating the jig supporting the electrode.

[0006] However, some of the generated fumes or spatter are not sucked into the suction part by the suction airflow and adhere to the jig. In addition, the adhered fumes continue to grow in specific parts of the jig.

[0007] Since the current collector of the electrode is a foil made of aluminum or copper and has a thickness of only a few micrometers, if the tab processed by laser notching the above-mentioned blank portion is interfered with even slightly by the fume fixed to the jig, the tab is easily bent or deformed.

[0008] Meanwhile, even if the tap does not directly come into contact with the fume adhering to the jig, the suction airflow affects the tap, causing vibration in the tap or bending the tap in the direction of the suction airflow. Therefore, it is difficult to increase the intensity of the suction airflow to prevent or suppress the adhering growth of the fume.

[0009] The present invention has been devised to solve the aforementioned problems and aims to provide a tap processing device that prevents the tap from being deformed by the suction airflow by eliminating the factor that causes the suction airflow to deform the tap.

[0010] The present invention aims to provide a tap processing device that can increase the intensity of the suction airflow without affecting the tap, thereby efficiently removing fumes and spatter generated during the laser notching process.

[0011] The technical problems of the present invention are not limited to the purposes mentioned above, and other unmentioned purposes and advantages of the present invention may be understood from the following description and will be more clearly understood by the embodiments of the present invention. Furthermore, it will be readily apparent that the purposes and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0012] The present invention can be applied to a tap processing device for processing an electrode tab in a non-tap portion provided at the end of the first direction in the width direction of an electrode constituting a secondary battery.

[0013] The above secondary battery may include an electrode assembly in which a first electrode and a second electrode are stacked with a separator interposed therebetween. One of the first electrode and the second electrode may be a positive electrode, and the other may be a negative electrode.

[0014] In some examples, the electrode assembly may be in the form of a jelly-roll in which a first electrode and a second electrode, each having a predetermined width and extended in the longitudinal direction, are wound in the longitudinal direction.

[0015] In some examples, the electrode assembly may be in the form of a stack cell in which a first electrode and a second electrode, each having a predetermined width and a predetermined length, are stacked in a stacking direction.

[0016] However, the structure of the electrode assembly is not limited to this.

[0017] The electrode may comprise a current collector and an active material laminated on the surface of the current collector. The current collector may be a foil sheet made of metal. The active material may be laminated on one or both surfaces of the sheet-shaped current collector.

[0018] The above electrode may include a retaining region in which an active material is laminated on one or both surfaces of a sheet-shaped current collector, and a non-retaining region in which the current collector is exposed because the active material is not laminated.

[0019] The above electrode may be in a form in which the above-mentioned portion is disposed at the end of the first direction in the width direction.

[0020] The above-described tap processing device includes a guide section that guides the electrode as it travels along the longitudinal direction, a cutting section that cuts the uncut portion in a tap processing area provided in the guide section, and a suction section that sucks gas near the tap processing area in the first direction.

[0021] The above guide portion comprises a first jig that guides the movement of the electrode by having a first guide surface that contacts the electrode, and a second jig that guides the movement of the unsupported portion by having a second guide surface that contacts the unsupported portion.

[0022] The first guide surface can come into contact with the retaining portion of the electrode. Accordingly, the first guide surface can come into contact with the active material of the electrode.

[0023] The first guide surface can be surface-treated to have a surface roughness lower than that of the material of the first jig. Due to the smooth first guide surface, even if the active material of the traveling electrode slips against the first guide surface, damage to the active material can be prevented.

[0024] The thickness of the first jig can be determined by the first guide surface of the first jig and the first opposing surface facing it.

[0025] The second jig is positioned on the first direction side of the first jig part and guides the movement of the unoccupied part of the electrode.

[0026] The second jig defines the tap processing area. The second jig guides the movement of the unseat portion of the electrode so that it passes through the tap processing area.

[0027] The first jig and the second jig may be manufactured as a single unit or as separate parts.

[0028] The first jig above may be in a fixed form despite the movement of the electrode.

[0029] In some examples, the first jig may include a first laminated member providing the first guide surface and a second laminated member laminated on the inner side of the first layer and providing the first opposing surface.

[0030] The first laminated member may include a porous material.

[0031] In some examples, the first jig may include a roller that is rotatably installed. The first guide surface may be provided on the outer surface of the roller.

[0032] The roller above is provided with a rim that provides the outer surface, and the inner surface of the rim may define the first opposing surface.

[0033] In some examples, the second jig may include a pair of cantilever members extending parallel to the direction of travel of the electrode from the outside of the tap processing area toward the tap processing area in the direction of travel of the electrode.

[0034] The above tap processing area can be defined by the gap between the pair of cantilever members in the traveling direction of the electrode.

[0035] The second guide surface can be provided on the surface of the cantilever member.

[0036] The thickness of the second jig may be determined by the thickness of the cantilever member. The thickness may be determined by the second guide surface and the second opposing surface facing the second guide surface.

[0037] The present invention provides a thickness reduction surface that reduces the thickness of the first jig at the first direction end of the first opposite surface of the first guide surface of the first jig.

[0038] The thickness reduction surface reduces the thickness near the first direction end of the first jig adjacent to the second jig, thereby suppressing the formation of an abrupt step difference between the first opposing surface and the second opposing surface at the boundary between the first jig and the second jig that are mutually adjacent in a direction parallel to the width direction of the electrode.

[0039] The suction unit generates an airflow in the form of a laminar flow parallel to the first direction near the tap processing area. If the step difference between the first opposing surface and the second opposing surface is reduced, the phenomenon of the laminar flow being separated by the step difference is further suppressed. Accordingly, the phenomenon in which the separated flow deforms the unexposed portion of the electrode tap can be prevented.

[0040] The suppression of the step difference can be implemented by applying at least one of the following structures: i) a thickness reduction structure that reduces the thickness near the first direction end of the first jig so that the thickness of the first jig corresponds to the thickness of the second jig, and ii) a tapering structure that applies a tapering treatment to the thickness reduction surface. The thickness reduction structure suppresses the step difference itself between the first jig and the second jig, thereby minimizing the cause of laminar flow delamination. The tapering structure diffuses the laminar flow before it reaches the step shape, thereby increasing resistance to laminar flow delamination caused by the step difference.

[0041] In some examples, the present invention may include a tapered surface such that the thickness reduction surface gradually decreases as it approaches the tap processing area in the first direction.

[0042] The above tapered surface may extend to the end of the first direction first jig adjacent to the above tap processing area.

[0043] The above-mentioned tapered surface may provide a straight surface profile or include a gentle curved surface profile. That is, the angle of inclination that the tapered surface makes with the first direction may be constant or gradually change in the section where the tapered surface is formed in the first direction.

[0044] The angle of inclination formed by the thickness reduction surface with the first direction may be 0 degrees or more and 60 degrees or less.

[0045] The angle of inclination that the tapered surface makes with the first direction may be greater than 0 degrees and less than or equal to 60 degrees. Preferably, the angle of inclination that the tapered surface makes with the first direction may be 15 degrees or more and 45 degrees or less. More preferably, the angle of inclination that the tapered surface makes with the first direction may be 25 degrees to 35 degrees.

[0046] The thickness reduction surface may include a section extending parallel to the first direction. In the section, the thickness of the first jig defined by the thickness reduction surface may be 0.5 mm or more and 5 mm or less.

[0047] The above section may be extended to the first direction end of the first jig. Additionally, the first direction end of the first jig may be trimmed.

[0048] The cutting section may include a laser irradiator that irradiates a laser onto the unlit portion of the tap processing area in a second direction that intersects both the driving direction of the electrode and the first direction.

[0049] The suction unit may include a suction nozzle that is positioned to face the first jig with the second jig in between in the first direction and extends in the first direction.

[0050] According to the present invention, the step difference between the boundary area of ​​the first jig and the second jig is mitigated by providing a tapered surface near the end of the first jig adjacent to the second jig or by reducing the thickness of the first jig itself. Accordingly, flow separation of the suction airflow that may occur in the area can be suppressed, thereby providing a stronger suction force.

[0051] According to the present invention, by suppressing the phenomenon in which suction flow causes deformation of the electrode tab, fumes and spatter generated during the laser processing of the electrode tab can be effectively removed without deformation of the electrode tab caused by suction flow.

[0052] In addition to the effects described above, the specific effects of the present invention are described together with the specific details for implementing the invention below.

[0053] FIG. 1 is an exploded view of the first electrode, the first separator, the second electrode, and the second separator constituting the electrode assembly of the first embodiment.

[0054] FIG. 2 is a stacked unfolded view of the first electrode, the first separator, the second electrode, and the second separator constituting FIG. 1.

[0055] Figure 3 is a diagram showing the process of winding around a core with a separator interposed between the first electrode and the second electrode of Figure 1.

[0056] Figure 4 is a perspective view of an electrode assembly in the form of a cylindrical jelly-roll assembled by winding it as in Figure 3 in the stacked form of Figure 2.

[0057] FIG. 5 is a perspective view showing a state in which a first current collector plate is joined to a first electrode tab provided at the first axial end of an electrode assembly facing the first end wall of a can.

[0058] FIG. 6 is a perspective view showing a state in which a second current collector plate is joined to a second electrode tab provided at the axial second end of an electrode assembly facing the second end wall of a can.

[0059] FIG. 7 is a side cross-sectional perspective view of a battery cell case according to the present invention.

[0060] Figure 8 is a cross-sectional view of a battery cell.

[0061] Figure 9 is a plan view of the state in which tap processing is performed on the untapped portion of the electrode.

[0062] FIG. 10 is a perspective view of the guide portion of the tap processing device of the first embodiment.

[0063] FIG. 11 is a perspective view showing the process of notching by guiding the movement of the electrode by the guide part of FIG. 10 and irradiating the tap processing area with a laser using a laser irradiator.

[0064] FIG. 12 is a perspective view showing a suction nozzle installed to remove fumes and spatter generated during the laser notching process of FIG. 11.

[0065] Fig. 13 is a side view of Fig. 12.

[0066] Fig. 14 is a cross-sectional view of Fig. 13-14-14.

[0067] Figure 15 is a diagram showing a simulation of the airflow generated by the suction part in the space opposite the guide surface of the first jig and the second jig.

[0068] FIG. 16 is a diagram showing a simulation of the airflow generated by the suction part in the space opposite the guide surface of the first jig and the second jig, with the inclination angle of the tapered surface of the tap processing device of the first embodiment being different.

[0069] FIG. 17 is a perspective view of the guide portion of the tap processing device of the second embodiment.

[0070] FIG. 18 is a perspective view showing the process of notching by guiding the movement of the electrode by the guide part of FIG. 17 and irradiating the tap processing area with a laser using a laser irradiator.

[0071] FIG. 19 is a perspective view showing a suction nozzle installed to remove fumes and spatter generated during the laser notching process of FIG. 18.

[0072] Fig. 20 is a side view of Fig. 19.

[0073] FIG. 21 is a cross-sectional view of FIG. 20, section 21-21.

[0074] [Explanation of the symbol]

[0075] 10: Can (Housing) 11: Sidewall 114: Beading section 118: Crimping section 12: First end wall 16: Second end wall, lid 17: Gasket 20: Electrode assembly 21: First electrode 22: Second electrode 23: Current collector 24: Active material 25: Retaining section 26: Non-retaining section 27: Electrode tab 27-1: First electrode tab 27-2: Second electrode tab 28: Separator 29: Winding core hollow section 290: Winding core shaft 30: First current collector plate 31: First region 32: Second region 33: Bridge section 40: Second current collector plate 41: Center section 42: Edge section 43: Arm section 50: First electrode terminal 51: Gasket 60: Insulator 70: Tab Processing device 72: Suction section 74: Suction nozzle 76: Cutting section 78: Laser irradiator 80: Guide section 81: First jig 81a: First guide surface 81b: First opposing surface 81c: Thickness reduction surface 81d: Tapered surface 811: First laminated member 812: Second laminated member 813: Roller 814: Rim 815: Spoke 82: Second jig 82a: Second guide surface 82b: Second opposing surface 825: Cantilever member A: Tap processing area

[0076] The aforementioned objectives, features, and advantages are described in detail below with reference to the attached drawings, thereby enabling those skilled in the art to easily implement the technical concept of the present invention. In describing the present invention, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such descriptions would unnecessarily obscure the essence of the invention. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0077] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0078] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0079] In the following, the statement that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0080] In addition, where it is stated that one component is "connected," "combined," or "in contact" with another component, it should be understood that while the components may be directly connected or in contact with each other, another component may be "interposed" between each component, or each component may be "connected," "combined," or "in contact" through another component.

[0081] Singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "composed of" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be omitted or additional components or steps may be included.

[0082] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less unless specifically stated otherwise.

[0083] In describing the embodiments, the longitudinal direction of the electrode refers to the direction in which the electrode is wound, and the width direction of the electrode refers to a direction perpendicular to the longitudinal direction. The electrode can be understood as a sheet form extended in the longitudinal and width directions. The axial direction of the electrode assembly refers to the direction in which the axis forming the winding center of the jelly-roll type electrode assembly extends, the radial (radial) direction refers to a direction approaching or moving away from the axis, and the circumferential (circumferential) direction refers to a direction surrounding the axis.

[0084] In describing the embodiments below, repetitive descriptions common to different embodiments may be omitted. That is, it is obvious that an example of one embodiment and an example of another embodiment can be combined, substituted, or omitted to implement another embodiment.

[0085] [Battery Cell]

[0086] Referring to FIGS. 1 to 8, the battery cell of the embodiment is implemented in a cylindrical shape. The battery cell includes an electrode assembly (20), a current collector plate (30, 40) electrically connected to the electrode assembly (20), and a case (10) that accommodates the electrode assembly (20) and the current collector plate (30, 40).

[0087] The electrode assembly (20) can be manufactured into a cylindrical jelly-roll shape as shown in FIG. 4 by preparing a first electrode (21), a second electrode (22), and a separator (28) that are extended in the longitudinal direction with a predetermined width as shown in FIG. 1, stacking them in the order of the first electrode (21), the separator (28), the second electrode (22), and the separator (28) as shown in FIG. 2, and winding them around a core shaft (290) as shown in FIG. 3.

[0088] One of the first electrode (21) and the second electrode (22) may be an anode and the other may be a cathode. An embodiment implements the first electrode (21) as an anode and the second electrode (22) as a cathode.

[0089] The first electrode (21) and the second electrode (22) are manufactured in the form of a sheet extending in the longitudinal direction with a predetermined width. The electrodes are manufactured in the form in which an active material (24) is coated on a current collector (23).

[0090] The current collector (23) may be made of metal foil. One of the current collector (23) of the first electrode (21) and the current collector (23) of the second electrode (22) may be made of aluminum, and the other may be made of copper. An embodiment implements the current collector (23) of the first electrode (21) as aluminum foil and the current collector (23) of the second electrode (22) as copper foil.

[0091] The above electrode may include not only an area where the active material (24) is coated on the current collector (23), but also an area where the active material (24) is not coated on the current collector (23). For convenience of explanation, in a two-dimensional area defined by the sheet-shaped current collector (23), the area where the active material (24) is applied and capable of causing a battery reaction is referred to as the electrode retaining portion (25), and the area where the active material (24) is not applied and thus does not cause a battery reaction is referred to as the electrode uncoated portion (26). According to this explanation, the area where the active material (24) is not applied on both sides of the sheet-shaped current collector (23) may be the electrode uncoated portion (26) since it is an area where a battery reaction does not occur. On the other hand, even if the active material is coated on only one side of the current collector (23) in the electrode, if at least a portion of the said coated area is in contact with another electrode and a separator (28) in between, since this is an area where a battery reaction can occur in a two-dimensional area defined by the sheet-shaped electrode, the area where the active material (24) is coated on at least one side of the current collector (23) may be the electrode holding portion (25).

[0092] The non-electric portion (26) of the above electrode may be provided for a function or operation other than the battery reaction. For example, the non-electric portion (26) may provide an electrode tab (27) that electrically connects the electrode to an electrode terminal. Specifically, the current collector (23) of the non-electric portion (26) itself may be utilized as the electrode tab (27). Of course, a separate tab member may be attached to the current collector (23) of the non-electric portion (26) to provide the electrode tab.

[0093] According to the embodiment, the first electrode (21) is provided with a non-removable portion (26) at the first end in the width direction, and the second electrode (22) is provided with a non-removable portion (26) at the second end in the width direction.

[0094] Referring to FIGS. 2 and 4, the unoccupied portion (26) region protrudes outward in the widthwise or axial direction from the electrode laminate or jelly-roll. The unoccupied portion (26) itself functions as an electrode tab (27). In the widthwise or axial direction, the inner end of the unoccupied portion (26) is positioned further inward than the outer end of the separator (28), and the outer end of the unoccupied portion (26) is positioned further outward than the outer end of the separator (28).

[0095] Referring to FIGS. 1 and FIGS. 2, the above-mentioned portion (26) may have incision lines formed at predetermined intervals to provide a plurality of flag-shaped electrode tabs (27) arranged along the longitudinal direction.

[0096] The embodiment implements the electrode tabs (27) in the shape of an isosceles trapezoid. In addition to this, the shape of the electrode tabs (27) may be various shapes such as a semicircle, a semi-ellipse, a triangle, a rectangle, a parallelogram, etc.

[0097] An embodiment is exemplified in which the electrode tabs (27) arranged along the longitudinal direction have the same width (longitudinal dimension). However, the width of the electrode tabs may gradually or stepwise widen from the core side to the outer circumference side.

[0098] In addition, the embodiment illustrates a form in which the height (axial dimension) of the electrode tabs (27) increases stepwise from the core side to the outer circumference side. However, the height of these electrode tabs may also be implemented as a constant or gradually decreasing form.

[0099] In addition, in the embodiment, a structure is exemplified in which the electrode tab (27) is removed from a predetermined section of the central end and a predetermined section of the centrifugal end of the non-removable portion (26). However, it is obvious that the electrode tab may not be removed from the central end of the non-removable portion, the electrode tab may not be removed from the centrifugal end of the non-removable portion, or neither may be removed.

[0100] In the jelly roll-shaped electrode assembly (20), the electrode tab (27) can be flattened by being bent radially as shown in FIG. 4. The electrode tab (27) can be bent radially inward or outward. In an embodiment, a structure in which the electrode tab (27) is bent radially inward is exemplified.

[0101] The electrode tabs (27) can be folded one by one during the process of winding a laminate to form a jelly roll-shaped electrode assembly (20) as shown in FIG. 3. Alternatively, the electrode tabs (27) may be folded simultaneously after winding a laminate to form a jelly roll-shaped electrode assembly. The electrode assembly (20) may also be manufactured by winding an electrode and a separator while the electrode tabs (27) are pre-folded, and then finally folding the electrode tabs (27).

[0102] The electrode tabs (27) of the first electrode (21) and the electrode tabs (27) of the second electrode (22), which are folded and overlapped in the radial direction in this way, can each provide a first plane and a second plane that are substantially perpendicular to the axial direction at both axial ends of the electrode assembly (20).

[0103] As shown in FIGS. 5 and 6, a first current collector plate (30) and a second current collector plate (40) can be joined to the substantially flat first surface and second surface, respectively, provided by bending the electrode tabs (27) that are exposed at each axial end of the electrode assembly (20).

[0104] One of the first current collector plate (30) and the second current collector plate (40) may be a positive current collector plate and the other may be a negative current collector plate. In an embodiment, the first current collector plate (30) is a positive current collector plate and the second current collector plate (40) is a negative current collector plate.

[0105] The first current collector plate (30) and the second current collector plate (40) may include copper or aluminum materials. An embodiment is implemented such that the first current collector plate (30) includes aluminum material and the second current collector plate (40) includes copper material.

[0106] Referring to FIG. 5, the first current collector plate (30) includes a first region (31) provided in a portion corresponding to the core hollow (29) of the electrode assembly (20), and a second region (32) provided around the first region (31). The first region (31) is positioned at the center of the first current collector plate (30) and is provided in a form that covers at least a portion of the core hollow (29) of the electrode assembly (20) in the axial direction. The second region (32) is provided in a form that surrounds the first region (31) while being spaced radially apart from the first region (31). The first region (31) and the second region (32) are physically and electrically connected to each other through a bridge portion (33). The second region (32) is electrically connected by being joined to a first electrode tab (27-1) provided on the first electrode (21) of the electrode assembly (20), and the first region (31) can be electrically connected by being joined to a first electrode terminal (50) to be described later.

[0107] Referring to FIG. 6, the second current collector plate (40) comprises a central portion (41) including a ring-shaped portion with a hole formed in the center, and an edge portion (42) surrounding the central portion (41) from the radial outer side of the central portion (41). The central portion (41) and the edge portion (42) are spaced apart in the radial direction, and the second current collector plate (40) further comprises an arm portion (43) connecting the central portion (41) and the edge portion (42). The central portion (41) can be electrically connected by being joined to a second electrode tab (27-2) provided on the second electrode (22) of the electrode assembly (20). The edge portion (42) can be electrically connected by being joined to at least one of the side wall (11) and the second end wall (16) of the can (10) to be described later.

[0108] Referring to FIGS. 7 and FIGS. 8, the electrode assembly (20) can be inserted into a case (10) with the first current collector plate (30) and the second current collector plate (40) joined together as shown in FIGS. 5 and FIGS. 6.

[0109] The above case (10) may include a metal can. The can (10) includes a side wall (11) extending axially between a first end and a second end, and a first end wall (12) connected to the first end of the side wall (11) and extending radially. The first end wall (12) may form a flat disc shape intersecting the axial direction, and the side wall (11) may be a circular tube shape extending along the axial direction.

[0110] A hole is provided in the center of the first end wall (12), and a first electrode terminal (50) can be fitted into the hole. The first electrode terminal (50) can be fixed to the first end wall (12) by insulating and sealing it. For insulating and sealing, for example, the first electrode terminal (50) can be fixed to the first end wall (12) by riveting it with a gasket (51) interposed.

[0111] The second end of the above side wall (11) is open to define the opening of the can (10).

[0112] The electrode assembly (20) is received in the can (10) with the first current collector plate (30) aligned toward the first end wall (12) of the can (10). An insulator (60) is interposed between the first current collector plate (30) and the first end wall (12) to electrically insulate the first current collector plate (30) and the first end wall (12) from each other.

[0113] The first region (31) of the first current collector plate (30) can be electrically connected to and fixed to the first electrode terminal (50). For example, the first electrode terminal (50) fixed to the can (10) can be fixed and electrically connected by being joined to the surface of the first region (31) of the first current collector plate (30) by a thermal bonding method such as welding. The first electrode terminal (50) of the can (10) and the first region (31) can be connected after the electrode assembly (20) is placed in the can (10).

[0114] Accordingly, the first electrode terminal (50) may have a first polarity corresponding to the first electrode (21).

[0115] Then, the lower portion of the side wall (11) of the can (10) is plastically processed to form a beading portion (114) that is radially inwardly recessed in the side wall (11), and a second current collector plate (40) is heat-bonded to the beading portion (114) by means such as welding. Accordingly, the can (10) can have a second polarity corresponding to the second electrode (22).

[0116] In this state, an electrolyte is injected into the interior of the can (10), and the opening is sealed by covering it with a second end wall (16) in the form of a lid or cap. In the embodiment, after injecting the electrolyte, the edge of the lid (16) is fitted into the beading portion (114), and the end of the side wall (11) is caulked radially inward to form a crimping portion (118) that is bent radially inward. Accordingly, a gasket (17) is interposed between the edge of the lid (16) and the side wall (11), and the edge of the lid (16) is compressed and fixed between the beading portion (114) and the crimping portion (118).

[0117] Meanwhile, unlike the embodiment in which the second end wall (16) is fixed by processing the beading portion (114) and the crimping portion (118), the edge portion (42) of the second collector plate (40) may be electrically connected by thermal bonding to at least one of the axial second end portion of the side wall (11) and the radial outer circumference portion of the second end wall (16), and the radial outer circumference portion of the second end wall (16) may be sealed and fixed to the axial second end portion of the side wall (11) by a thermal bonding method such as welding. According to this, the can (10) and the second end wall (16) may have a second polarity corresponding to the second electrode (22).

[0118] The first end wall (12) is electrically connected to the side wall (11). Therefore, the first end wall (12) can also have a second polarity. The diameter of the head portion of the first electrode terminal (50) positioned on the outer side of the first end wall (12) may be about one-third of the diameter of the first end wall (12). That is, the surface of the first end wall (12) may have a sufficient area for a bus bar to be joined. Accordingly, the first end wall (12) can form a second electrode terminal.

[0119] [Electrode Tab Processing Device]

[0120] A first embodiment of a processing device for processing the electrode tab of the electrode is described below with reference to FIGS. 9 to 16.

[0121] As illustrated in FIG. 9, the electrode tab (27) of the electrode (21, 22) is formed by laser notching along a predetermined path on the unlit portion (26). The laser notching can be performed by irradiating a laser onto the unlit portion (26) located at the first end in the width direction of the traveling electrode (21, 22).

[0122] A tap processing device (70) for laser notching the unused portion of the electrodes (21, 22) comprises a guide portion (80) that guides the electrodes (21, 22) as they travel along the longitudinal direction, a cutting portion (76) that cuts the unused portion (26) in a tap processing area (A) provided in the guide portion (80), and a suction portion (72) that sucks in gas near the tap processing area (A) in a direction parallel to the first direction.

[0123] Referring to FIG. 10, the guide portion (80) comprises a first jig (81) that guides the movement of the electrodes (21, 22) by having a first guide surface (81a) that contacts the electrodes (21, 22), and a second jig (82) that guides the movement of the unsupported portion (26) by having a second guide surface (82a) that contacts the unsupported portion (26). The second jig (82) is positioned on the first direction side of the first jig (81) portion to guide the movement of the unsupported portion (26) of the electrodes (21, 22). The first guide surface (81a) and the second guide surface (82a) provide surfaces that face the surface of the moving electrodes (21, 22).

[0124] The second jig (82) defines a tap processing area (A). The second jig (82) guides the movement of the unsupported portion (26) of the electrodes (21, 22) so that the unsupported portion (26) passes through the tap processing area (A).

[0125] The second jig (82) comprises a pair of cantilever members (825) that extend parallel to the direction of travel of the electrodes (21, 22) from the outside of the tap processing area (A) toward the tap processing area (A) in the direction of travel of the electrodes (21, 22). The tap processing area (A) is defined by the gap between the pair of cantilever members (825) in the direction of travel of the electrodes (21, 22), and the second guide surface (82a) is provided on the surface of the cantilever members (825).

[0126] The cantilever member (825) may be made of a metal material. The surface of the cantilever member (825) may be treated to reduce the friction coefficient with respect to the metal foil of the uncoated portion (26) and to prevent the deposition of fumes generated during the laser notching process. The cantilever member (825) is extended in an arc shape. Accordingly, the uncoated portion (26) is kept taut while receiving a certain amount of tension in the tap processing area (A).

[0127] The first guide surface (81a) is in contact with the retaining portion of the electrode (21, 22). Accordingly, the first guide surface (81a) is in contact with the active material of the electrode (21, 22).

[0128] In the embodiment, the first guide surface (81a) is surface-treated to have a lower surface roughness than the material of the first jig (81). The smooth first guide surface (81a) prevents the surface of the active material layer from being damaged even if the active material of the traveling electrode (21, 22) makes sliding contact with the first guide surface (81a).

[0129] In the first embodiment, the first jig (81) is implemented in a fixed form despite the movement of the electrodes (21, 22).

[0130] The first jig (81) and the second jig (82) may be manufactured as a single unit or as separate parts. In the first embodiment, the second jig (82) is manufactured as a separate part from the first jig (81). Accordingly, when fumes adhere to the second jig (82) beyond an allowable range, the second jig (82) is removed from the guide part (80) and a new second jig (82) is installed, allowing the tap processing device (70) to be used continuously.

[0131] In the first embodiment, the first jig (81) has a structure in which a first stacked member (811) providing the first guide surface (81a) and a second stacked member (812) disposed inside the first layer are stacked.

[0132] The first laminated member (811) may be a porous material that does not damage the active material (24) of the electrodes (21, 22), and the second laminated member (812) may be a rigid material that maintains the shape of the first laminated member (811). A passage may be provided at the rear of the second laminated member (812) through which an airflow formed by the suction part (72), which will be described later, can flow.

[0133] Referring to FIGS. 11 and 12, the cutting portion (76) can be implemented by a laser irradiator (78) that irradiates a laser (L) onto a blank portion (26) of the tap processing area (A) in a second direction that intersects both the travel direction of the electrodes (21, 22) and the first direction. The area of ​​the laser (L) irradiates back and forth on the blank portion (26) in a direction parallel to the width direction of the electrodes while the electrodes (21, 22) are traveling, thereby forming a predetermined laser notching line on the blank portion (26). Accordingly, the blank portion (26) can be cut along the laser notching line.

[0134] The fumes generated during the laser notching process of the unnotched portion (26) of the metal foil can be removed by sucking in air around the tap processing area (A), thereby preventing the fumes from adhering to the guide portion (80) around the tap processing area (A). Referring to FIGS. 12 and 13, the suction portion (72) installed for this purpose includes a suction nozzle (74) that is positioned to face the first jig (81) with the second jig (82) in between in the first direction and extends in the first direction. By the suction nozzle (74), an airflow in a direction parallel to the first direction is generated around the tap processing area (A), and the air sucked in by the suction nozzle (74) is discharged to the outside.

[0135] Referring to FIGS. 13 and 14, the second stacked member (812) of the first jig (81) provides a first opposing surface (81b) that faces the first guide surface (81a) and faces the passage. Accordingly, the thickness (t1) of the first jig (81) can be determined by the distance between the first guide surface (81a) and the first opposing surface (81b) of the first jig (81).

[0136] Meanwhile, the thickness (t2) of the second jig (82) may be determined by the thickness of the cantilever member (825). The thickness may be determined by the second guide surface (82a) of the cantilever member (825) and the second opposing surface (82b) facing the second guide surface (82a).

[0137] In the vicinity of the above-mentioned tap processing area (A), the first guide surface (81a) and the second guide surface (82a) may have a fine step difference approximately the thickness of the coating of the active material (24) on one side of the electrode (21, 22). Accordingly, even if the first guide surface (81a) and the second guide surface (82a) guide the movement of the retaining portion (25) and the unsupported portion (26) of the electrode (21, 22), respectively, the unsupported portion (26) can be extended straight along the width direction of the electrode (21, 22) without bending in the boundary area with respect to the retaining portion (25).

[0138] The first jig (81) and the second jig (82) define a passage that causes a laminar flow of air to occur in the tap processing area (A) in a direction parallel to the first direction by the suction part (72) in the area behind the first guide surface (81a) and the second guide surface (82a), that is, where the first opposing surface (81b) and the second opposing surface (82b) face each other. Accordingly, the fumes generated during the laser notching process are immediately discharged to the outside through the suction nozzle (74) before they adhere to the first jig (81) or the second jig (82).

[0139] Referring to FIG. 15, generally, the thickness (t1) of the first jig (81) implemented with the first laminated member (811) and the second laminated member (812) may be greater than the thickness (t2) of the cantilever member (825). Due to this step (t1-t2), the flow line flowing near the step portion in the first direction laminar flow of air generated by the suction portion (72) is separated at the step portion and becomes a vortex swirling around the corner area provided by the step portion. This vortex acts as a force pulling the electrode tab (27) portion within the tap processing area (A) processed by laser notching into the rear space. Due to the characteristics of the thin metal foil, if the intensity of the vortex exceeds a certain amount, the electrode tab (27) bends backward, and if the electrodes (21, 22) are driven while the electrode tab (27) is bent backward, there is a risk that the part of the electrode tab (27) bent backward may collide with the cantilever member (825) of the second jig (82) or the fume attached thereto and be deformed.

[0140] The suppression of the above step difference can be implemented by applying at least one of the following structures: i) a thickness reduction structure that reduces the thickness near the first direction end of the first jig (81) so that the thickness of the first jig (81) corresponds to the thickness of the second jig (82), and ii) a tapering structure that tapered the thickness reduction surface (81c).

[0141] In order to prevent the above phenomenon, the present invention provides a thickness reduction surface (81c) that reduces the thickness of the first jig (81) at the first direction end of the first opposing surface (81b) of the first guide surface (81a) of the first jig (81).

[0142] The thickness reduction surface (81c) reduces the thickness near the first direction end of the first jig (81) adjacent to the second jig (82), thereby preventing the first opposing surface (81b) and the second opposing surface (82b) from forming a steep step difference at the boundary area between the first jig (81) and the second jig (82) that are mutually adjacent in a direction parallel to the width direction of the electrodes (21, 22).

[0143] In the first embodiment, the thickness reduction surface (81c) is implemented as a tapering structure. According to the first embodiment, the thickness reduction surface (81c) includes a tapered surface (81d) such that the thickness of the first jig (81) gradually decreases as it approaches the tap processing area (A) in the first direction. The tapered surface (81d) is formed to extend to the end of the first jig (81) in the first direction adjacent to the tap processing area (A).

[0144] Accordingly, the laminar flow is diffused before reaching the step shape, thereby increasing resistance to laminar flow separation caused by the step, and thus minimizing the formation of vortices caused by the step.

[0145] The above-mentioned tapered surface (81d) may provide a straight surface profile or include a gentle curved surface profile. That is, the angle of inclination that the tapered surface (81d) makes with the first direction may be constant or gradually change in the section where the tapered surface (81d) is formed in the first direction. The first embodiment is implemented as a tapered surface (81d) in the form of a straight surface profile.

[0146] Referring to FIG. 14, in contrast to a structure in which the tapered surface (81d) is not provided as shown in FIG. 15, the tapered surface (81d) can also have the effect of reducing the thickness (t1) of the first direction end of the first jig (81) to the thickness (t2) of the second jig (82).

[0147] Referring to FIG. 16, the angle of inclination (θ) that the tapered surface (81d) makes with the first direction may be greater than 0 degrees and less than or equal to 60 degrees. If the angle of inclination is too small, it is difficult to expect diffusion of laminar flow and there is almost no effect of reducing the thickness (t1), and if the angle of inclination exceeds 60 degrees, there is no effect of mitigating laminar flow separation. Preferably, the angle of inclination that the tapered surface (81d) makes with the first direction may be greater than 15 degrees and less than or equal to 45 degrees. As illustrated, when the angle of inclination is between 15 and 45 degrees, the length of the vortex-forming region in the first direction can be suppressed. More preferably, the angle of inclination that the tapered surface (81d) makes with the first direction may be between 25 and 35 degrees. The closer the angle of inclination is to 30 degrees, the more the length of the vortex-forming region in the first direction can be reduced.

[0148] Even if the angle of inclination is close to 0, if the length of the first direction of the tapered surface is increased, the thickness (t1) of the first direction end of the first jig (81) can be sufficiently reduced, and as previously discussed, if the angle of inclination is 45 degrees or less, the effect of suppressing vortex formation to the extent that it does not affect the electrode tab can be expected. Taking this into account, in the embodiment, the angle of inclination is set to 0 to 45 degrees.

[0149] Meanwhile, in addition to the angle of inclination being close to 0, if the thickness reduction surface (81c) itself is offset from the first opposing surface (81b) in the opposite direction of the second direction, the thickness (t1) of the first direction end of the first jig (81) can be sufficiently reduced. Including these factors, in a preferred embodiment, the angle of inclination formed by the thickness reduction surface (81c) with the first direction may be 0 degrees or more and 45 degrees or less.

[0150] This thickness reduction structure suppresses the step difference between the first jig (81) and the second jig (82), thereby minimizing the cause of laminar flow delamination. The thickness reduction structure is further described in the tap processing device of the second embodiment described below.

[0151] With reference to FIGS. 17 to 21, a second embodiment of a processing device for processing the electrode tab of the electrode is described below. In describing the second embodiment, the differences from the first embodiment are described in detail. Therefore, matters not specifically mentioned in describing the second embodiment can be sufficiently understood from the first embodiment above.

[0152] Referring to FIG. 17, the guide portion (80) is provided with a first jig (81) that guides the movement of the electrodes (21, 22) by having a first guide surface (81a) that contacts the electrodes (21, 22) on its circumferential surface, and a second jig (82) that guides the movement of the uninformed portion (26) by having a second guide surface (82a) that contacts the uninformed portion (26).

[0153] The first jig (81) is implemented in the form of a roller (813) that is rotatably installed in correspondence with the moving electrodes (21, 22). The rotation axis of the roller (813) may be parallel to the width direction of the electrode. The first guide surface (81a) is provided on the outer surface of the roller (813). Specifically, the roller (813) is provided with a rim (814) that provides an outer surface defining the first guide surface (81a), and the inner surface of the rim (814) defines the first opposing surface (81b). The outer surface of the rim (814) is surface-treated so as not to damage the active material of the moving electrode, as previously described.

[0154] The thickness of the first jig (81) that affects the airflow generated by the air intake operation of the suction part (72) is defined by the first guide surface (81a) and the first opposing surface (81b). In the second embodiment, the thickness of the first jig (81) is determined by the thickness of the rim (814) area adjacent to the second jig (82). On the first opposing surface (81b) of the rim (814) area adjacent to the second jig (82), a thickness reduction surface (81c) extending parallel to the first direction is provided. The thickness reduction surface is formed by offsetting the first opposing surface in the direction of thickness reduction. Due to the thickness reduction surface (81c), the step difference (t1-t2) in the boundary section between the first jig (81) and the second jig (82) is significantly mitigated. The offset section may extend to the first direction end of the first jig (81). The offset section may be provided in a part of the first direction end of the first jig (81) or in the entire first opposing surface (81b). An embodiment illustrates that the offset section is provided in the entire surface. However, for the rigidity of the first jig (81), the offset section may be provided in only a part.

[0155] The thickness of the first jig (81), defined by the thickness reduction surface (81c) in the above offset section, may be 0.5 mm or more and 5 mm or less.

[0156] Due to the thin thickness of the offset section, there is a possibility that a sharp shape may be formed at the first direction end of the first jig (81) during the manufacturing process of the first jig (81). To prevent this, the first direction end of the first jig (81) may be trimmed during the manufacturing process of the first jig (81).

[0157] The rear of the rim (814), that is, the space facing the first opposing surface (81b), is provided in a form where airflow can be generated by the suction part (72). Referring to FIGS. 20 and 21, the rim (814) is spaced apart from the center of rotation of the roller (813) in the radial direction, and the rim (814) and the center of rotation are interconnected by spokes (815) that extend in the radial direction. A plurality of spokes (815) are spaced apart along the circumferential direction. Accordingly, even if the first jig (81) rotates in response to the movement of the electrodes (21, 22), the airflow area can be continuously provided.

[0158] The suction part (72) generates a laminar airflow parallel to the first direction near the tap processing area (A). According to the second embodiment, there is almost no step difference between the first opposing surface (81b) and the second opposing surface (82b), so the phenomenon of the laminar flow being separated by the step difference is further suppressed. Accordingly, the phenomenon of the separated flow deforming the unused portion (26) of the electrode (21, 22) tap can be prevented.

[0159] According to the above embodiment, flow separation is suppressed by a tapering structure that tapered the thickness reduction surface (81c), or by a thickness reduction structure that reduced the thickness near the first direction end of the first jig (81) so that the thickness of the first jig (81) corresponds to the thickness of the second jig (82). Although not directly presented in the embodiment, it is obvious that the thickness reduction structure and the tapering structure can be implemented together. For example, it is possible to implement a thickness reduction structure by generally having an offset section on the first opposing surface of the first jig, and to apply a tapering structure by forming a tapered surface at the first direction end of the first jig.

[0160] The embodiments described above should be understood as exemplary in all respects and not limiting, and the scope of the invention will be defined by the claims set forth below rather than by the detailed description above. Furthermore, the meaning and scope of the claims set forth below, as well as all modifications and variations derived from equivalents thereof, should be interpreted as being included within the scope of the invention.

[0161] Although the present invention has been described above with reference to the illustrated drawings, the present invention is not limited by the embodiments and drawings disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration according to the present invention were not explicitly described while describing the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

Claims

1. A tap processing device for processing an electrode tap in a non-tap portion provided at the end of the first direction in the width direction of an electrode, A guide part that guides the above electrode to travel along the longitudinal direction; A cutting part for cutting the blank portion in a tap processing area provided in the guide part; and It includes a suction unit that sucks gas near the tap processing area in the first direction; The above guide part is: A first jig having a first guide surface in contact with the electrode to guide the movement of the electrode; and A second jig is disposed on the first direction side of the first jig portion, defines the tap processing area, and has a second guide surface in contact with the non-tap portion to guide the movement of the non-tap portion so that the non-tap portion of the electrode passes through the tap processing area; and A tap processing device having a thickness reduction surface that reduces the thickness of the first jig provided at the first direction end of the first opposing surface of the first guide surface of the first jig.

2. A tapping device according to claim 1, wherein the thickness reduction surface includes a tapered surface such that the thickness of the first jig gradually becomes thinner as it approaches the tapping area in the first direction.

3. A tapping device according to claim 2, wherein the angle of inclination formed by the tapered surface with the first direction is greater than 0 degrees and less than or equal to 60 degrees.

4. A tapping device according to claim 3, wherein the angle of inclination formed by the tapered surface with the first direction is 15 degrees or more to 45 degrees or less.

5. A tapping device according to claim 2, wherein the tapered surface extends to the end of the first jig in the first direction adjacent to the tapping area.

6. A tap processing device according to claim 1, wherein the thickness reduction surface includes a section extending parallel to the first direction, and the thickness of the first jig defined by the thickness reduction surface in the section is 0.5 mm or more and 5 mm or less.

7. A tapping device according to claim 1, wherein a trimming portion is formed at the first direction end of the first jig.

8. A tap processing device according to claim 1, wherein the first jig comprises a first laminated member providing the first guide surface and a second laminated member laminated on the inner side of the first layer and providing the first opposing surface.

9. A tap processing device according to claim 8, wherein the first laminated member comprises a porous material.

10. A tapping device according to claim 1, wherein the first guide surface is surface-treated to have a surface roughness lower than that of the material of the first jig.

11. In claim 1, the first jig comprises a roller that is rotatably installed, and A tap processing device, wherein the first guide surface is provided on the outer circumference of the roller.

12. In claim 11, the roller comprises a rim that provides the outer surface, and A tapping device in which the inner circumferential surface of the above rim defines the above first opposing surface.

13. A tap processing device according to claim 11, wherein the cutting part comprises a laser irradiator that irradiates a laser to the unlit part in a second direction that intersects both the driving direction of the electrode and the first direction.

14. A tap processing device according to claim 1, wherein the suction part comprises a suction nozzle extended in the first direction and positioned opposite to the first jig with the second jig in between in the first direction.

15. In claim 1, the second jig comprises a pair of cantilever members extending parallel to the direction of travel of the electrode from the outer side of the tap processing area toward the tap processing area in the direction of travel of the electrode, and A tapping device in which the above-mentioned tapping area is defined by the gap between the pair of cantilever members in the traveling direction of the electrode.

Images