Forming device and forming method
Patent Information
- Application Number
- KR1020250026410
- Authority / Receiving Office
- KR · KR
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2026-09-04
Smart Images
Figure P1020250026410_ABST
Abstract
Description
Technology Field
[0001] The present invention relates to a forming device and a forming method, and more specifically, to a jelly roll forming device and a jelly roll forming method for forming a jelly roll of a cylindrical secondary battery capable of repeated charging and discharging. Background Technology
[0002] Cylindrical secondary batteries utilized a structure in which a tab connecting the jelly roll and the external terminal was welded to the electrode-free portion of the jelly roll; however, this structure had the problem of a limited current path and high intrinsic resistance of the jelly roll.
[0003] To solve this problem, attempts have been made to increase the number of tabs connected to the jelly roll, but the application of such methods has had limitations. To address this issue, one can consider notching the positive and negative sections, respectively provided at the top and bottom of the jelly roll, into multiple segments and utilizing them as positive and negative tabs. In other words, one can consider a method of implementing electrical connection using positive tabs (segments of the positive section) and negative tabs (segments of the negative section) that extend upward and downward, respectively, parallel to the extension direction of the jelly roll's winding center axis.
[0004] As such, when the positive and negative sections extending from the top and bottom of the jelly roll, respectively, are notched into multiple sections and are to be used as positive and negative tabs, respectively, the positive and negative tabs must each be folded toward the center of the jelly roll to increase the bonding area with the current collector plate.
[0005] Conventionally, to bend these positive and negative tabs, the positive and negative tabs were each pressed using jigs provided on both sides of the jelly roll. In this case, since the jigs pressed the positive and negative tabs in a direction parallel to the extended direction of the tabs, there was a problem in that the positive and negative tabs were bent in a direction other than the center of the jelly roll. Additionally, since the jigs pressed the positive and negative tabs only once, the tabs were bent relatively weakly and unraveled after a certain period of time. The problem to be solved
[0006] The present invention was devised in recognition of the above-mentioned problems and aims to provide a jelly roll forming device and a jelly roll forming method that prevent bending defects from occurring during the bending of the positive and negative tabs of a jelly roll. means of solving the problem
[0007] A forming device according to the present invention is a forming device for forming a jelly roll wound with a first electrode, a second electrode having opposite polarity to the first electrode, and a separator, and may include: a first forming unit that bends a first electrode tab of the first electrode provided on one side of the jelly roll toward the central axis of the jelly roll; a second forming unit that bends a second electrode tab of the second electrode provided on the other side of the jelly roll toward the central axis of the jelly roll; and a pressure inducing unit that induces the first forming unit and the second forming unit to press the one side and the other side of the jelly roll toward the center of the jelly roll after the first electrode tab and the second electrode tab are bent.
[0008] The first forming unit may include a first receiving portion that accommodates one side of the jelly roll; and a first air injection portion that injects air into the first electrode tab to bend the first electrode tab toward the central axis of the jelly roll.
[0009] The first receiving portion may include a housing having one end open and the other end closed, forming a receiving space in which one side of the jelly roll is received; and a cover covering at least a portion of the housing.
[0010] The first air injection unit may include a plurality of passages formed in the wall of the housing and having an opening communicating with the receiving space; and an air pump that supplies air to the plurality of passages.
[0011] Multiple of the above-mentioned Euros can be arranged at equal intervals along the circumferential direction of the housing.
[0012] The second forming unit may include a second receiving portion that receives the other side of the jelly roll; and a second air injection portion that injects air into the second electrode tab to bend the second electrode tab toward the central axis of the jelly roll.
[0013] The above-mentioned pressure induction unit may include a housing moving part that moves the housing toward the second receiving part.
[0014] The above housing moving part may include a rail extended in a horizontal direction; and a moving member that moves along the rail and moves the housing toward the second receiving part.
[0015] The first receiving portion may further include a rod that is formed in the housing and inserted into the jelly roll core portion, which is an empty space provided on the inner side of the jelly roll.
[0016] The first forming unit may further include a rotary motor coupled to the housing to rotate the housing in one direction.
[0017] A bearing may be provided between the housing and the cover.
[0018] The above rod may include a cylindrical pin that is formed to protrude toward the second receiving portion from the inner surface of the housing and has a portion exposed to the outside of the housing.
[0019] One end of the above pin can have its edge filleted.
[0020] A pin hole may be formed in the second receiving portion, into which one end of the pin is inserted when the housing moves toward the second receiving portion.
[0021] Meanwhile, the forming method according to the present invention is a forming method for forming a jelly roll wound with a first electrode, a second electrode having polarity opposite to that of the first electrode, and a separator, and may include: a first bending step of bending a first electrode tab of the first electrode provided on one side of the jelly roll toward the central axis of the jelly roll; a second bending step of bending a second electrode tab of the second electrode provided on the other side of the jelly roll toward the central axis of the jelly roll; and a third bending step of pressing each of the one side and the other side of the jelly roll toward the center of the jelly roll to bend the first electrode tab and the second electrode tab again.
[0022] The first bending step may include the step of injecting air into the first electrode tab to bend the first electrode tab toward the central axis of the jelly roll.
[0023] The second bending step may include the step of injecting air into the second electrode tab to bend the second electrode tab toward the central axis of the jelly roll.
[0024] The forming method according to the present invention may further include a core forming step of forming a jelly roll core portion, which is an empty space provided inside the jelly roll, into a cylindrical shape.
[0025] The above third bending step and the above core forming step can be performed simultaneously.
[0026] The core forming step described above may include a step of inserting a cylindrical rod into the jelly roll core and then rotating the rod to form the shape of the jelly roll core to match the shape of the rod. Effects of the invention
[0027] According to the forming device and forming method of the present invention, after bending the first electrode tab and the second electrode tab provided on one side and the other side of the jelly roll, respectively, the one side and the other side of the jelly roll can be additionally pressed, thereby preventing bending defects of the first electrode tab and the second electrode tab. Brief explanation of the drawing
[0028] FIG. 1 is a perspective view showing a forming device according to the present invention. FIG. 2 is a diagram illustrating that a first electrode, a second electrode, and a separator are wound to form a jelly roll. FIG. 3 is a cross-sectional view illustrating that the first forming unit forms the first electrode tab. FIG. 4 is a cross-sectional view illustrating that the second forming unit forms the second electrode tab. Figure 5 is a drawing illustrating the appearance of the formed first electrode tab. FIG. 6 is a drawing for explaining the structure of one end of a rod included in the first forming unit. FIG. 7 is a cross-sectional view showing a rotary motor coupled to a first forming unit. FIG. 8 is a cross-sectional view showing a rotary motor coupled to a second forming unit. FIG. 9 is a flowchart illustrating the steps of a forming method according to the present invention in sequence. Specific details for implementing the invention
[0029] Hereinafter, preferred embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in various different forms and may be limited or restricted by the following embodiments. The first air injection unit (112) preferably continues to inject air from before one side of the jelly roll (10) is inserted into the first receiving space (S1), rather than injecting air into the first electrode tab (11a) after one side of the jelly roll (10) is completely inserted into the first receiving space (S1). The first electrode tab (11a) has its tip fixed to the jelly roll (10) and its end can move relatively freely compared to the tip. However, if the first air injection unit (112) injects air after one side of the jelly roll (10) is completely inserted into the first receiving space (S1), the air will apply pressure to the tip of the first electrode tab (11a). Then, more air pressure is required to bend the first electrode tab (11a), and among the plurality of first electrode tabs (11a), the first electrode tabs (11a) that are relatively adjacent to the core part (C) may not be bent. On the other hand, if the first air injection part (112) continues to inject air from before one side of the jelly roll (10) is inserted into the first receiving space (S1), the air applies pressure from the end to the tip of the first electrode tab (11a). Then, it is not possible to easily bend the plurality of first electrode tabs (11a) that are relatively adjacent to the core part (C) with less air pressure.
[0030] In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the explanation or could unnecessarily obscure the essence of the invention have been omitted. Furthermore, when assigning reference numerals to the components of each drawing in this specification, identical or similar reference numerals are assigned to identical or similar components throughout the entire specification.
[0031] In addition, terms or words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.
[0032] Hereinafter, a forming device and a forming method according to the present invention will be described with reference to the drawings.
[0034] Forming device
[0035] FIG. 1 is a perspective view showing a forming device according to the present invention. FIG. 2 is a drawing for explaining that a first electrode, a second electrode, and a separator are wound to form a jelly roll.
[0036] Referring to FIGS. 1 and 2, the forming device (100) according to the present invention forms a jelly roll (10) wound with a first electrode (11), a second electrode (12) having opposite polarity to the first electrode (11), and a separator (13). The device comprises a first forming unit (110) that bends a first electrode tab (11a) of the first electrode (11) provided on one side of the jelly roll (10) toward the central axis of the jelly roll (10), a second forming unit (120) that bends a second electrode tab (12a) of the second electrode (12) provided on the other side of the jelly roll (10) toward the central axis of the jelly roll (10), and after the first electrode tab (11a) and the second electrode tab (12a) are bent, the first forming unit (110) and the second forming unit (120) [form] the one side and the other side of the jelly roll (10). It may include a pressure inducing unit (130) that induces pressure in the direction of the center of the jelly roll (10).
[0037] The first and second forming units (110, 120) can bend the first electrode tab (11a) and the second electrode tab (12a) toward the central axis of the jelly roll (10), and then press one side and the other side of the jelly roll (10) by the pressure induction unit (130). When the first and second forming units (110, 120) press one side and the other side of the jelly roll (10) by the pressure induction unit (130), the first electrode tab (11a) and the second electrode tab (12a) can be bent again toward the central axis of the jelly roll (10).
[0038] That is, the forming device (100) according to the present invention can fold each of the first electrode tab (11a) and the second electrode tab (12a), which are provided at each end of the jelly roll (10), twice, thereby preventing the first electrode tab (11a) and the second electrode tab (12a) from being folded in a direction other than the center direction of the jelly roll (10). In addition, it can also prevent the first electrode tab (11a) and the second electrode tab (12a) from unfolding again after a predetermined time.
[0039] The jelly roll (10) is an electrode assembly in which a first electrode (11), a second electrode (12), and a separator (13) having a sheet shape are stacked and then wound in one direction from one end to the other, and each of the first electrode (11), the second electrode (12), and the separator (13) may have a structure wound with respect to the central axis of the jelly roll (10). At this time, the separator (13) is provided between the first electrode (11) and the second electrode (12) and can prevent short circuits between the first electrode (11) and the second electrode (12).
[0040] The first electrode (11) and the second electrode (12) are electrodes having opposite polarities to each other. When the first electrode (11) is a positive electrode, the second electrode (12) is a negative electrode, and when the first electrode (11) is a negative electrode, the second electrode (12) may be a positive electrode. The positive electrode and the negative electrode may each have a structure in which an active material layer is formed on an electrode current collector in the form of a metal foil or a metal mesh. The active material layer may be formed by dispersing granular active material, conductive material, binder, plasticizer, etc., in a solvent to form a slurry, stirring the mixture, applying the active material slurry to the electrode current collector, and then removing the solvent during a drying process. Additionally, there may be an electrode-free portion in which an active material layer is not formed in a part of the electrode current collector.
[0041] Conventionally, a positive tab and a negative tab were attached to the positive and negative electrode sections, respectively; the positive tab attached to the positive section was electrically connected to the cap assembly of the cylindrical battery, and the negative tab attached to the negative section was electrically connected to the bottom of the battery can of the cylindrical battery. However, recently, a jelly roll has been introduced in which a portion of the electrode section is used as an electrode tab without a separate electrode tab being attached to the electrode section.
[0042] The jelly roll (10) in the present invention also has a structure in which a separate electrode tab is not attached to the electrode blank portion of the first electrode (11) and the second electrode (12), and the electrode blank portion of the first electrode (11) and the second electrode (12) is used as an electrode tab. An electrode blank portion in which an active material layer is not formed may be formed at one end of each of the first electrode (11) and the second electrode (12) having a sheet shape, and each of these electrode blank portions may be processed into a plurality of segmented pieces that can be independently folded. To this end, processes such as laser notching, ultrasonic cutting, and punching may be performed on the electrode blank portions of each of the first electrode (11) and the second electrode (12).
[0043] A plurality of segments formed in the electrode-free portion of the first electrode (11) can subsequently be folded in the direction of the central axis of the jelly roll (10) and electrically connected to the cap assembly of the cylindrical battery or the lower part of the battery can of the cylindrical battery. That is, each of the plurality of segments formed in the electrode-free portion of the first electrode (11) can become an electrode tab (11a) of the first electrode (11).
[0044] Meanwhile, a plurality of segments formed in the electrode-free portion of the second electrode (12) can subsequently be folded in the direction of the central axis of the jelly roll (10) and electrically connected to the lower part of the battery can of the cylindrical battery or the cap assembly of the cylindrical battery. That is, each of the plurality of segments formed in the electrode-free portion of the second electrode (12) can become an electrode tab (12a) of the second electrode (12).
[0045] At this time, since the first electrode tab (11a) and the second electrode tab (12a) are respectively provided on one side and the other side of the jelly roll (10), when the first electrode tab (11a) is connected to the cap assembly of the cylindrical battery, the second electrode tab (12a) can be connected to the bottom of the battery can of the cylindrical battery. Conversely, when the first electrode tab (11a) is connected to the bottom of the battery can of the cylindrical battery, the second electrode tab (12a) can be connected to the cap assembly of the cylindrical battery.
[0046] The separator (13) is a sheet provided between the first electrode (11) and the second electrode (12) to prevent a short circuit between the first electrode (11) and the second electrode (12), and the separator (13) may have a larger surface area than the first electrode (11) and the second electrode (12). This separator (13) may be composed of an insulating material. For example, the separator (13) may be composed of a polyolefin-based polymer material such as polyethylene (PE) or polypropylene (PP).
[0047] FIG. 3 is a cross-sectional view illustrating that the first forming unit forms the first electrode tab.
[0048] Referring to FIG. 3 and the like, the first forming unit (110) is a unit that bends a first electrode tab (11a) provided on one side of the jelly roll (10) toward the central axis of the jelly roll (10), and may be a unit that performs air forming by injecting air into the first electrode tab (11a) while receiving at least a portion of the first electrode tab (11a) inside. The first forming unit (110) may include a first receiving part (111) that receives one side of the jelly roll (10) and a first air injection part (112) that injects air into the first electrode tab (11a) to bend the first electrode tab (11a) toward the central axis of the jelly roll (10).
[0049] The first receiving portion (111) may include a first housing (1111) that forms a first receiving space (S1) in which one side of the jelly roll (10) is received, with one end open and the other end closed, and a first cover (1112) that surrounds at least a part of the first housing (1111).
[0050] The first housing (1111) is a case that accommodates one side of the jelly roll (10) and the first electrode tab (11a) provided therein. Inside the first housing (1111), a first receiving space (S1) with a shape in which one end is shielded and the other end is open may be provided. The first receiving space (S1) may have a shape corresponding to one side of the jelly roll (10). In particular, the first receiving space (S1) may have a cylindrical shape in which one end is shielded and the other end is open, and the diameter of the first receiving space (S1) may be equal to or slightly larger than the diameter of the jelly roll (10). In this case, since one side of the jelly roll (10) is fitted into the first receiving space (S1), the jelly roll (10) can be prevented from detaching from the first receiving space (S1) even while air forming of the first electrode tab (11a) is performed.
[0051] The first cover (1112) is configured to enclose at least a portion of the first housing (1111) and may have various structures. For example, the first cover (1112) may have a hollow cylindrical shape that encloses a portion of the outer surface of the first housing (1111). Meanwhile, since no restraining member is provided between the first housing (1111) and the first cover (1112) to restrain them, the first housing (1111) can move independently of the first cover (1112) by means of the pressure induction unit (130).
[0052] Meanwhile, the first air injection unit (112) injects air into the first electrode tab (11a) contained in the first receiving space (S1) to bend the first electrode tab (11a) in the direction of the central axis of the jelly roll (10). The first air injection unit (112) may include a plurality of flow paths (1121) formed in the wall portion of the first housing (1111) and having an opening (1121a) connected to the first receiving space (S1), and an air pump (not shown) that supplies air to the plurality of flow paths (1121).
[0053] It is preferable for the first air injection unit (112) to continuously inject air from before the one side of the jelly roll (10) is inserted into the first receiving space (S1), rather than injecting air into the first electrode tab (11a) after the one side of the jelly roll (10) is completely inserted into the first receiving space (S1). The first electrode tab (11a) has its tip fixed to the jelly roll (10) and its end can move relatively freely compared to the tip. However, if the first air injection unit (112) injects air after the one side of the jelly roll (10) is completely inserted into the first receiving space (S1), the air will apply pressure to the tip of the first electrode tab (11a). In this case, more air pressure is required to bend the first electrode tab (11a), and among the plurality of first electrode tabs (11a), the first electrode tabs (11a) that are relatively adjacent to the core part (C) may not be bent. On the other hand, if the first air injection part (112) continues to inject air from before one side of the jelly roll (10) is inserted into the first receiving space (S1), the air applies pressure from the end to the tip of the first electrode tab (11a). Then, even with less air pressure, multiple first electrode tabs (11a) relatively adjacent to the core part (C) can be easily bent.
[0054] The passage (1121) is a void space formed through the wall of the first housing (1111), and air ejected from the air pump can be supplied to the first receiving space (S1) through the plurality of passages (1121) and the openings (1121a) formed in each of the plurality of passages (1121). At this time, the openings (1121a) formed in each of the plurality of passages (1121) can face the central axis of the first housing (1111). Accordingly, the air supplied to the first receiving space (S1) through the plurality of openings (1121a) can bend the first electrode tab (11a) toward the central axis of the jelly roll (10).
[0055] Meanwhile, a plurality of channels (1121) may be arranged at equal intervals along the circumferential direction of the first housing (1111). That is, the openings (1121a) formed in each of the plurality of channels (1121) may be arranged at equal intervals along the circumferential direction on the inner surface of the first housing (1111). Additionally, the openings (1121a) formed in each of the plurality of channels (1121) may all have the same diameter. In this case, the first electrode tab (11a) accommodated in the first receiving space (S1) receives air of uniform pressure from all directions through the equally arranged openings (1121a), thereby allowing the first electrode tab (11a) to be uniformly bent toward the center of the jelly roll (10).
[0056] An air pump is a unit that supplies air to each of a plurality of flow paths (1121) and can be formed in various ways. For example, the air pump may include nozzles connected to each of the plurality of flow paths (1121) and an air supply unit that supplies air to these nozzles.
[0057] Meanwhile, the first forming unit (110) may include a first support member (113) that supports the first receiving portion (111). The first support member (113) is a member that is fixedly installed at various locations in the workspace where the entire forming operation of the jelly roll (10) is performed, and the first cover (1112) of the first receiving portion (111) may be fixedly installed on the upper side of the first support member (113). In this case, the first support member (113) and the first cover (1112) may not move even when an external force is applied. On the other hand, since no separate restraining member is provided between the first housing (1111) and the first cover (1112), the first housing (1111) may move by an external force separately from the first support member (113) and the first cover (1112).
[0058] FIG. 4 is a cross-sectional view illustrating that the second forming unit forms the second electrode tab.
[0059] Referring to FIG. 4 and the like, the second forming unit (120) is a unit that bends a second electrode tab (12a) provided on the other side of the jelly roll (10) toward the central axis of the jelly roll (10), and may be a unit that performs air forming by injecting air into the second electrode tab (12a) while receiving at least a portion of the second electrode tab (12a) inside. The second forming unit (120) may include a second receiving part (121) that receives the other side of the jelly roll (10) and a second air injection part (122) that injects air into the second electrode tab (12a) to bend the second electrode tab (12a) toward the central axis of the jelly roll (10).
[0060] The second receiving portion (121) may include a second housing (1211) that forms a second receiving space (S2) in which the other side of the jelly roll (10) is received, with one end open and the other end closed, and a second cover (1212) that surrounds at least a part of the second housing (1211).
[0061] The second housing (1211) is a case that accommodates the other side of the jelly roll (10) and the second electrode tab (12a) provided therein. Inside the second housing (1211), a second receiving space (S2) with a shape in which one end is shielded and the other end is open may be provided. The second receiving space (S2) may have a shape corresponding to the other side of the jelly roll (10). In particular, the second receiving space (S2) may have a cylindrical shape in which one end is shielded and the other end is open, and the diameter of the second receiving space (S2) may be equal to or slightly larger than the diameter of the jelly roll (10). In this case, since the other side of the jelly roll (10) is fitted into the second receiving space (S2), the jelly roll (10) can be prevented from escaping from the second receiving space (S2) even while air forming of the second electrode tab (12a) is performed.
[0062] The second cover (1212) is configured to enclose at least a portion of the second housing (1211) and may have various structures. For example, the second cover (1212) may have a hollow cylindrical shape that encloses a portion of the outer surface of the second housing (1211). Meanwhile, since no restraining member is provided between the second housing (1211) and the second cover (1212) to restrain them, the second housing (1211) can move independently of the second cover (1212) by means of the pressure induction unit (130).
[0063] Meanwhile, the second air injection unit (122) injects air into the second electrode tab (12a) contained in the second receiving space (S2) to bend the second electrode tab (12a) in the direction of the central axis of the jelly roll (10). The second air injection unit (122) may include a plurality of flow paths (1221) formed in the wall of the second housing (1211) and having an opening (1221a) connected to the second receiving space (S2), and an air pump (not shown) that supplies air to the plurality of flow paths (1221).
[0064] It is preferable for the second air injection unit (122) to continuously inject air from before the other side of the jelly roll (10) is inserted into the second receiving space (S2), rather than injecting air into the second electrode tab (12a) after the other side of the jelly roll (10) is completely inserted into the second receiving space (S2). The second electrode tab (12a) has its tip fixed to the jelly roll (10) and its end can move relatively freely compared to the tip. However, if the second air injection unit (122) injects air after the other side of the jelly roll (10) is completely inserted into the second receiving space (S2), the air will apply pressure to the tip of the second electrode tab (12a). In this case, more air pressure is required to bend the second electrode tab (12a), and among the plurality of second electrode tabs (12a), the second electrode tabs (12a) that are relatively adjacent to the core part (C) may not be bent. On the other hand, if the second air injection part (122) continues to inject air before the other side of the jelly roll (10) is inserted into the second receiving space (S2), the air applies pressure from the end to the tip of the second electrode tab (12a). Then, even with less air pressure, multiple second electrode tabs (12a) relatively adjacent to the core part (C) can be easily bent.
[0065] The passage (1221) is a void space formed through the wall of the second housing (1211), and air ejected from the air pump can be supplied to the second receiving space (S2) through the plurality of passages (1221) and the openings (1221a) formed in each of the plurality of passages (1221). At this time, the openings (1221a) formed in each of the plurality of passages (1221) can face the central axis of the second housing (1211). Accordingly, the air supplied to the second receiving space (S2) through the openings (1221a) can bend the second electrode tab (12a) toward the central axis of the jelly roll (10).
[0066] Meanwhile, a plurality of channels (1221) may be arranged at equal intervals along the circumferential direction of the second housing (1211). That is, the openings (1221a) formed in each of the plurality of channels (1221) may be arranged at equal intervals along the circumferential direction on the inner surface of the second housing (1211). Additionally, the openings (1221a) formed in each of the plurality of channels (1221) may all have the same diameter. In this case, the second electrode tab (12a) accommodated in the second receiving space (S2) receives air of uniform pressure from all directions through the equally arranged openings (1221a), thereby allowing the second electrode tab (12a) to be uniformly bent toward the center of the jelly roll (10).
[0067] An air pump is a unit that supplies air to each of a plurality of flow paths (1221) and can be formed in various ways. For example, the air pump may include a nozzle connected to each of the plurality of flow paths (1221) and an air supply unit that supplies air to these nozzles.
[0068] Meanwhile, the second forming unit (120) may include a second support member (123) that supports the second receiving part (121). The second support member (123) is a member that is fixedly installed at various locations in the workspace where the entire forming operation of the jelly roll (10) is performed, and the second cover (1212) of the second receiving part (121) may be fixedly installed on the upper side of the second support member (123). In this case, the second support member (123) and the second cover (1212) may not move even when an external force is applied. On the other hand, since no separate restraining member is provided between the second housing (1211) and the second cover (1212), the second housing (1211) may move by an external force separately from the second support member (123) and the second cover (1212).
[0069] Figure 5 is a drawing illustrating the appearance of the formed first electrode tab.
[0070] FIG. 5 illustrates the structure of one side of a jelly roll (10). A first electrode tab (11a) provided on one side of the jelly roll (10) is bent toward the central axis of the jelly roll (10). Specifically, the first electrode tabs (11a) provided on one side of the jelly roll (10) are bent toward the jelly roll core part (C) formed in the center of the jelly roll (10), and the bent first electrode tabs (11a) may not overlap with one surface of the jelly roll core part (C).
[0071] Meanwhile, the pressure inducing unit (130) is a unit that induces the first forming unit (110) and the second forming unit (120) to press one side and the other side of the jelly roll (10) toward the center of the jelly roll (10). In a state where each of the one side and the other side of the jelly roll (10) is received in the first receiving space (S1) of the first forming unit (110) and the second receiving space (S2) of the second forming unit (120), the first forming unit (110) and / or the second forming unit (120) may be a unit that moves the first forming unit (110) and / or the second forming unit (120) toward each other. In this case, as the first forming unit (110) and the second forming unit (120) move closer toward each other, the one side and the other side of the jelly roll (10) may be pressed toward the center of the jelly roll (10). In addition, the first electrode tab (11a) and the second electrode tab (12a), respectively provided on one side and the other side of the jelly roll (10), can be further folded in the direction of the central axis of the jelly roll (10).
[0072] Such a pressure induction unit (130) may include a housing moving part (131) that moves the first receiving part (111) toward the second receiving part (121). Specifically, the housing moving part (131) may be configured to move the first housing (1111) of the first receiving part (111) toward the second housing (1211) of the second receiving part (121) in a straight direction. At this time, since one side and the other side of the jelly roll (10) are each received in the first housing (1111) and the second housing (1211), the one side and the other side of the jelly roll (10) may be pressured toward the center of the jelly roll (10).
[0073] The housing moving part (131) may include a rail (1311) extended in a horizontal direction and a moving member (1312) that moves along the rail (1311) and moves the first housing (1111) toward the second receiving part (121). The rail (1311) is a horizontal guide member installed on a wall provided near the first forming unit (110), and the moving member (1312) is coupled to the first housing (1111) and moves along the rail (1311) together with the first housing (1111), and the rail (1311) and the moving member (1312) may have a conventional LM guide structure.
[0074] Meanwhile, although not illustrated in FIG. 5, the housing moving part (131) may be configured to move the second housing (1211) of the second receiving part (121) in a straight direction toward the first housing (1111) of the first receiving part (111). In this case, the housing moving part (131) may have an LM guide structure installed on a wall provided near the second forming unit (120).
[0075] Additionally, although not illustrated in FIG. 5, the pressurized induction unit (130) may be a robot arm coupled to the first forming unit (110) and / or the second forming unit (120) to move them toward each other.
[0076] Meanwhile, the first receiving portion (111) provided in the first forming unit (110) may include a rod (1113) that is inserted into the jelly roll core portion (C), which is an empty space formed in the first housing (1111) and provided inside the jelly roll (10). When the rod (1113) is inserted into the jelly roll core portion (C), the first forming unit (110) and the second forming unit (120) move closer to each other by the pressure induction unit (130), and the jelly roll core portion (C) can be formed to fit the shape of the inserted rod (1113).
[0077] Specifically, the rod (1113) may be a cylindrical pin (1113) that is formed to protrude from the inner surface of the first housing (1111) toward the second housing (1211) of the second receiving portion (121), with a portion exposed to the outside of the first housing (1111). At this time, a pin hole (1213) may be formed in the second housing (1211) of the second receiving portion (121) so that one end (1113a) of the pin (1113) is inserted when the first housing (1111) moves toward the second housing (1211) by the pressure induction unit (130).
[0078] When one side and the other side of the jelly roll (10) are accommodated in the first housing (1111) and the second housing (1211), a pin (1113) formed protruding from the inner surface of the first housing (1111) can penetrate the core portion (C) of the jelly roll (10). At this time, one end (1113a) of the pin (1113) can be inserted into a pin hole (1213) formed on the inner surface of the second housing (1211). Subsequently, when the distance between the first housing (1111) and the second housing (1211) is reduced by the pressure induction unit (130), the alignment of the core portion (C) of the jelly roll (10) can be adjusted to match the shape of the pin (1113). That is, when the pin (1113) is inserted into the core part (C) of the jelly roll (10) and the distance between the first housing (1111) and the second housing (1211) becomes close, the shape of the core part (C) of the jelly roll (10) can be formed to match the shape of the pin (1113).
[0079] FIG. 6 is a drawing for explaining the structure of one end of a rod included in the first forming unit.
[0080] Referring to FIG. 6, the end portion (1113a) of the pin (1113) may have its corners filled. Specifically, the end portion (1113a) of the pin (1113) may have its corners filled to form a rounded shape. At this time, the pin hole (1213) into which the end portion (1113a) of the pin (1113) is inserted may also have a rounded groove shape. In this case, since an angled tip is not formed on the end portion (1113a) of the pin (1113), it is possible to prevent scratches from occurring on the core portion (C) of the jelly roll (10) caused by the end portion (1113a) of the pin (1113) during the process of inserting the end portion (1113a) of the pin (1113) into the pin hole (1213).
[0081] FIG. 7 is a cross-sectional view showing a rotary motor coupled to a first forming unit. FIG. 8 is a cross-sectional view showing a rotary motor coupled to a second forming unit.
[0082] FIGS. 7 and 8 illustrate another embodiment of a forming device according to the present invention, and differ from the conventional embodiment in that the forming unit shown in FIGS. 7 and 8 further includes a rotary motor that rotates the housing.
[0083] The first forming unit (110') illustrated in FIG. 7 may include a first rotary motor (114') coupled to the first housing (1111') to rotate the first housing (1111') in one direction. The first rotary motor (114') may be coupled to the first housing (1111') in various ways. For example, the first rotary motor (114') may be coupled to the first housing (1111') inside the first housing (1111') to rotate the first housing (1111'). At this time, a bearing may be provided between the first housing (1111') and a first cover (1112') that surrounds a part of the outer surface of the first housing (1111') to minimize frictional force due to the rotation of the first housing (1111').
[0084] As described above, when the first housing (1111´) rotates, the pin (1113´) provided in the first housing (1111´) can also rotate together with the first housing (1111´). Specifically, when the distance between the first forming unit (110´) and the second forming unit (120´) becomes close, the pin (1113´) can rotate while inserted into the core of the jelly roll, thereby providing an advantageous effect of effectively forming the core of the jelly roll.
[0085] At this time, when the first housing (1111') rotates, the movable member (1312') coupled thereto may not rotate. Specifically, the movable member (1312') and the first housing (1111') may each be coupled by a coupling pin (p'). A pin fastening groove corresponding to the shape of the coupling pin (p') may be provided in each of the movable member (1312') and the first housing (1111'). In this case, even when the first housing (1111') rotates, a predetermined space exists between the coupling pin (p') and the pin fastening groove of the first housing (1111'), so the coupling pin (p') does not rotate, and the movable member (1312') may also not rotate.
[0086] Additionally, the second forming unit (120') illustrated in FIG. 8 may include a second rotary motor (124') coupled to the second housing (1211') to rotate the second housing (1211') in one direction. The second rotary motor (124') may be coupled to the second housing (1211') in various ways. For example, the second rotary motor (124') may be coupled to the second housing (1211') inside the second housing (1211') to rotate the second housing (1211'). At this time, a bearing may be provided between the second housing (1211') and a second cover (1212') that surrounds a part of the outer surface of the second housing (1211') to minimize frictional force due to the rotation of the second housing (1211').
[0088] Forming method
[0089] FIG. 9 is a flowchart illustrating the steps of a forming method according to the present invention in sequence.
[0090] Referring to FIG. 9, the forming method according to the present invention is a method for forming a jelly roll (10) in which a first electrode (11), a second electrode (12) having opposite polarity to the first electrode (11), and a separator (13) are wound, and may include a first bending step (S110) of a first electrode tab (11a) of a first electrode (11) provided on one side of the jelly roll (10) being bent toward the central axis of the jelly roll (10), a second bending step (S120) of a second electrode tab (12a) of a second electrode (12) provided on the other side of the jelly roll (10) being bent toward the central axis of the jelly roll (10), and a third bending step (S130) of pressing each of the one side and the other side of the jelly roll (10) toward the center of the jelly roll (10) to bend the first electrode tab (11a) and the second electrode tab (12a) again.
[0091] The forming method according to the present invention can fold each of the first electrode tab (11a) and the second electrode tab (12a), which are provided at each end of the jelly roll (10), twice, thereby preventing the first electrode tab (11a) and the second electrode tab (12a) from being folded in a direction other than the center direction of the jelly roll (10). In addition, it can also prevent the first electrode tab (11a) and the second electrode tab (12a) from unfolding again after a predetermined time.
[0092] The aforementioned first bending step (S110) may be a step of bending the first electrode tab (11a) toward the central axis of the jelly roll (10) by injecting air into the first electrode tab (11a). Specifically, the first bending step (S110) may be a step of air forming the first electrode tab (11a), wherein, while one side of the jelly roll (10) is received in a first receiving space (S1) formed within a first housing (1111) of a first forming unit (110), air is injected through a plurality of openings (1121a) communicating toward the first receiving space (S1) to bend the first electrode tab (11a) provided on one side of the jelly roll (10) toward the central axis of the jelly roll (10).
[0093] The aforementioned second bending step (S120) may be a step of bending the second electrode tab (12a) toward the central axis of the jelly roll (10) by injecting air into the second electrode tab (12a). Specifically, the second bending step (S120) may be a step of air forming the second electrode tab (12a), wherein, while the other side of the jelly roll (10) is received in a second receiving space (S2) formed within the second housing (1211) of the second forming unit (120), air is injected through a plurality of openings (1221a) communicating toward the second receiving space (S2) to bend the second electrode tab (12a) provided on the other side of the jelly roll (10) toward the central axis of the jelly roll (10).
[0094] The aforementioned third folding step (S130) may be a step of folding the first electrode tab (11a) and the second electrode tab (12a) again by applying physical pressure to them. Specifically, the third folding step (S130) may be a step of pressing the first and other sides of the jelly roll (10) by bringing the distance between the first forming unit (110) and the second forming unit (120) closer while the first and other sides of the jelly roll (10) are respectively housed in the first receiving space (S1) and the second receiving space (S2). At this time, the first electrode tab (11a) provided on one side of the jelly roll (10) and the second electrode tab (12a) provided on the other side of the jelly roll (10) may be folded in the direction of the central axis of the jelly roll (10). At this time, the distance between the first forming unit (110) and the second forming unit (120) can be reduced as the pressurizing induction unit (130) moves the first forming unit (110) and / or the second forming unit (120) toward each other.
[0095] The forming method according to the present invention may further include a core forming step (S140) for forming a jelly roll core part (C), which is an empty space provided inside the jelly roll (10), into a cylindrical shape. The core forming step (S140) may be a step of forming the shape of the jelly roll core part (C) to match the shape of the rod (1113) by inserting a cylindrical rod (1113) into the jelly roll core part (C) and then rotating the rod (1113). The rod (1113) rotates together with the first housing (1111) of the first forming unit (110), and the rotation of the first housing (1111) may be performed by a rotation motor coupled thereto.
[0096] Meanwhile, the third bending step (S130) and the core forming step (S140) can be performed simultaneously. That is, the process of pressing one side and both sides of the jelly roll (10) toward the center of the jelly roll (10) and the process of rotating the rod (1113) inserted into the core part (C) of the jelly roll (10) can be performed simultaneously.
[0097] Specifically, with one side and the other side of the jelly roll (10) each being received in the first receiving space (S1) and the second receiving space (S2), respectively, the process of a pressure induction unit (130) moving the first forming unit (110) and / or the second forming unit (120) toward each other and the process of a rotary motor rotating the rod (1113) while the rod (1113) provided in the first forming unit (110) is inserted into the core part (C) of the jelly roll (10) can be performed simultaneously.
[0098] In this case, the process of re-folding the first electrode tab (11a) and the second electrode tab (12a) and the process of forming the core part (C) of the jelly roll (10) into a cylindrical shape are performed simultaneously, so there is an advantageous effect of shortening the time required for the overall forming of the jelly roll (10).
[0100] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and various implementations 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. Explanation of the symbols
[0102] 10: Jelly Roll 11: First electrode 11a: First electrode tab 12: Second electrode 12a: Second electrode tab 13: Separator 100: Forming device 110, 120: Forming Unit 111, 121: Reception Department 112, 122: Air injection unit 113, 123: Support 130: Pressurized induction unit 131: Housing moving part 1311: Rail 1312: Moving part S110: 1st bending step S120: 2nd bending step S130: 3rd bending step S140: Core forming stage
Claims
Claim 1 A forming device for forming a jelly roll wound with a first electrode, a second electrode having opposite polarity to the first electrode, and a separator, comprising: a first forming unit that bends a first electrode tab of the first electrode provided on one side of the jelly roll toward the central axis of the jelly roll; a second forming unit that bends a second electrode tab of the second electrode provided on the other side of the jelly roll toward the central axis of the jelly roll; and a pressure inducing unit that, after the first electrode tab and the second electrode tab are bent, induces the first forming unit and the second forming unit to press the one side and the other side of the jelly roll toward the center of the jelly roll. Claim 2 A forming device according to claim 1, wherein the first forming unit comprises: a first receiving portion for receiving one side of the jelly roll; and a first air injection portion for injecting air into the first electrode tab to bend the first electrode tab toward the central axis of the jelly roll. Claim 3 A forming device according to claim 2, wherein the first receiving portion comprises: a housing having one end open and the other end closed, forming a receiving space in which one side of the jelly roll is received; and a cover covering at least a portion of the housing. Claim 4 A foaming device according to claim 3, wherein the first air injection unit comprises a plurality of flow paths formed in the wall of the housing and having an opening communicating with the receiving space; and an air pump for supplying air to the plurality of flow paths. Claim 5 In claim 4, a plurality of the fluid paths are formed in equal intervals along the circumferential direction of the housing. Claim 6 A forming device according to claim 3, wherein the second forming unit comprises: a second receiving portion for receiving the other side of the jelly roll; and a second air injection portion for injecting air into the second electrode tab to bend the second electrode tab toward the central axis of the jelly roll. Claim 7 In claim 6, the pressure induction unit comprises a housing moving part that moves the housing toward the second receiving part, forming device. Claim 8 A forming device according to claim 7, wherein the housing moving part comprises: a rail extending in a horizontal direction; and a moving member that moves along the rail and moves the housing toward the second receiving part. Claim 9 A forming device according to claim 3, wherein the first receiving portion further comprises a rod inserted into a jelly roll core portion, which is a hollow space provided inside the jelly roll and is formed in the housing. Claim 10 In claim 9, the first forming unit further comprises a rotary motor coupled to the housing and rotating the housing in one direction. Claim 11 A forming device according to claim 10, wherein a bearing is provided between the housing and the cover. Claim 12 A forming device according to claim 10, wherein the rod is formed to protrude toward the second receiving portion from the inner surface of the housing and includes a cylindrical pin with a portion exposed to the outside of the housing. Claim 13 In claim 12, one end of the pin is a forming device in which the edge is filleted. Claim 14 A forming device according to claim 12, wherein a pin hole is formed in the second receiving portion, into which one end of the pin is inserted when the housing moves toward the second receiving portion. Claim 15 A forming method for forming a jelly roll wound with a first electrode, a second electrode having opposite polarity to the first electrode, and a separator, comprising: a first bending step of bending a first electrode tab of a first electrode provided on one side of the jelly roll toward the central axis of the jelly roll; a second bending step of bending a second electrode tab of a second electrode provided on the other side of the jelly roll toward the central axis of the jelly roll; and a third bending step of pressing each of the one side and the other side of the jelly roll toward the center of the jelly roll to bend the first electrode tab and the second electrode tab again. Claim 16 A forming method according to claim 15, wherein the first bending step comprises the step of blowing air onto the first electrode tab to bend the first electrode tab toward the central axis of the jelly roll. Claim 17 A forming method according to claim 15, wherein the second bending step comprises the step of injecting air into the second electrode tab to bend the second electrode tab toward the central axis of the jelly roll. Claim 18 A forming method according to claim 15, further comprising a core forming step of forming a jelly roll core portion, which is an empty space provided inside the jelly roll, into a cylindrical shape. Claim 19 A forming method according to claim 18, wherein the third bending step and the core forming step are performed simultaneously. Claim 20 In claim 19, the core forming step comprises the step of inserting a cylindrical rod into the jelly roll core and then rotating the rod to form the shape of the jelly roll core to match the shape of the rod.