Electrode sheet rewinding device including position-changeable idler roller

Abstract

The present invention relates to an electrode sheet rewinding device for rewinding an electrode sheet that has passed a part of a secondary battery electrode manufacturing process, the electrode sheet rewinding device comprising: a bobbin on which a PET film is wound; a bobbin holder configured to hold the bobbin; a bottom plate located below the bobbin holder, the bottom plate configured to support the bobbin holder; a roller-type contact roller configured to press the electrode sheet rewound around the bobbin above the bobbin to prevent the electrode sheet from bending; a vertical plate located on one side of the bottom plate, the contact roller being attached to the vertical plate; and an idle roller unit, the idle roller unit being configured to form the electrode sheet rewound around the bobbin into a tangent of the contact roller together with the contact roller, wherein the idle roller unit comprises an idle roller, a first drive device and a second drive device, the idle roller being configured to maintain the tension of the rewound electrode sheet and form the electrode sheet into a tangent of the contact roller, the first drive device and the second drive device being configured to change the position of the idle roller.

Description

Technical Field

[0001] This application claims priority to Korean Patent Application No. 2020-00125808, filed on September 28, 2020, which is hereby incorporated by reference herein in its entirety.

[0002] The present invention relates to an electrode sheet rewinding device, which includes an idle roller whose position can be changed, and the idle roller can automatically connect a PET film connected to the electrode sheet to the electrode sheet rewinding device before the electrode sheet is rewound to form a roller feeding path. Background Art

[0003] With the technological development of mobile devices such as smartphones, laptops, and digital cameras and the increase in demand for them, research on secondary batteries that can be charged and discharged has been actively conducted. In addition, secondary batteries as energy sources to replace fossil fuels that cause air pollution have been applied to electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and energy storage systems (ESSs).

[0004] Currently widely used secondary batteries include lithium secondary batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. In particular, research and development of lithium secondary batteries having high operating voltage and high energy density per unit weight have been actively carried out.

[0005] This secondary battery includes an electrode assembly having a structure in which electrodes and separators are alternately stacked, and a housing configured to accommodate the electrode assembly. The electrode assembly is a power generation element having a structure in which positive electrodes and negative electrodes are stacked with separators interposed therebetween, and the electrode assembly is classified into a wound electrode assembly or a stacked electrode assembly, the wound electrode assembly having a structure in which a long sheet-type positive electrode plate applied with an active material and a long sheet-type negative electrode plate applied with an active material are wound with separators interposed therebetween, and the stacked electrode assembly having a structure in which a plurality of positive electrode plates of a predetermined size and a plurality of negative electrode plates of a predetermined size are sequentially stacked with separators interposed therebetween.

[0006] A stacked folding type electrode assembly has been developed as an electrode assembly with an advanced structure that combines a wound type electrode assembly and a stacked type electrode assembly, the stacked folding type electrode assembly having a structure of a single cell or a double cell of a predetermined unit size folded using a long continuous separation membrane, each single cell having a positive electrode / separator / negative electrode structure, and each double cell having a positive electrode (negative electrode) / separator / negative electrode (positive electrode) / separator / positive electrode (negative electrode) structure.

[0007] In addition, in order to improve the processability of a conventional stacked electrode assembly and meet the needs of various secondary batteries, a laminated stacked electrode assembly has also been developed. The laminated stacked electrode assembly has a structure of stacked unit cells, in each unit cell, electrodes and separators are laminated to each other in an alternating stacked state.

[0008] The positive electrode for the electrode assembly is manufactured by applying a mixture of a positive electrode active material, a conductive agent, and a binder to a positive electrode current collector such as a metal foil and drying the mixture. A filler may be further added to the mixture as needed.

[0009] In addition, the negative electrode is manufactured by applying the negative electrode material to the negative electrode current collector and drying the negative electrode material. The components described with respect to the positive electrode may be optionally further included as needed.

[0010] After passing through a part of the electrode manufacturing process (eg, a slotting process or a drying process), the electrode sheet is stored or transported in a state of being rewound on a bobbin.

[0011] The electrode sheet rewound on the bobbin is unwound for use in subsequent processing. At this time, in order to solve the problem that the innermost part of the electrode sheet cannot be used, before the electrode sheet is rewound, a predetermined length of PET film is wound on the bobbin while the bobbin is empty.

[0012] When the electrode sheet is not directly rewound on the empty bobbin but is rewound on the empty bobbin while being connected to the PET film, the disadvantage that a part of the end portion of the electrode sheet cannot be used when the electrode sheet wound on the bobbin is unwound can be compensated.

[0013] However, in order to rewind the electrode sheet using the PET film, it is necessary to unwind the PET film from the bobbin before rewinding the electrode sheet, to maintain the tension of the electrode sheet together with the contact roller located above the bobbin, and to supply the PET film to an idle roller capable of performing rewinding of the electrode sheet, thereby forming a roller feeding path process.

[0014] Conventionally, such a PET film supply process is manually performed by workers, whereby work efficiency is reduced and foreign materials are generated due to the movement of the workers. Summary of the invention

[0015] Technical issues

[0016] The present invention is proposed in view of the above problems, and its object is to provide an electrode sheet rewinding device, which has a structure in which the position of an idle roller can be changed by a first driving device and a second driving device, so that before rewinding the electrode sheet, the PET film connected to the electrode sheet is automatically connected to the electrode sheet rewinding device to form a roller feeding path.

[0017] Technical Solution

[0018] In order to achieve the above-mentioned purpose, the electrode sheet rewinding device according to the present invention includes: a bobbin on which a PET film is wound; a bobbin holder configured to hold the bobbin; a base plate located below the bobbin holder, configured to support the bobbin holder; a roller-type contact roller, configured to press the electrode sheet rewound around the bobbin above the bobbin to prevent the electrode sheet from bending; a vertical plate located on one side of the base plate, the contact roller being attached to the vertical plate; and an idle roller unit, configured to form the electrode sheet rewound around the bobbin into a tangent of the contact roller together with the contact roller, wherein the idle roller unit includes an idle roller, a first drive device and a second drive device, the idle roller being configured to maintain the tension of the rewound electrode sheet and form the electrode sheet into a tangent of the contact roller, and the first drive device and the second drive device being configured to change the position of the idle roller.

[0019] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, the idle roller unit may further include a guide roller configured to maintain tension of the electrode sheet together with the idle roller.

[0020] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, the idle roller unit may further include an upper frame, the first driving device is disposed above the upper frame, and the second driving device is disposed below the upper frame.

[0021] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, the idle roller unit may further include a lower frame located below the second driving device, the lower frame being configured to fix the idle roller unit to the bottom plate.

[0022] In addition, in the electrode sheet rewinding device according to the present invention, the first driving device may include a driving shaft, a first gear connected to the driving shaft, and an idle roller support, one side of the idle roller support is rotatably connected to the driving shaft, and the other side is connected to the idle roller, whereby the first driving device can make the idle roller rotate from a position perpendicular to the floor to a position parallel to the floor.

[0023] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, the upper frame may include a second gear meshing with the first gear, the second gear being configured to rotate the first gear.

[0024] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, a second driving device may be located between the upper frame and the lower frame to linearly move the idle roller in a direction parallel to the floor.

[0025] Furthermore, the electrode sheet rewinding apparatus according to the present invention may further include a PET film sensor.

[0026] Furthermore, in the electrode sheet rewinding apparatus according to the present invention, the PET film sensor may be attached to the base plate or the bobbin holder.

[0027] Furthermore, the battery cell according to the present invention is manufactured using the electrode sheet rewinding apparatus according to the present invention.

[0028] Furthermore, the battery module according to the present invention includes the battery cell according to the present invention.

[0029] Beneficial Effects

[0030] The electrode sheet rewinding apparatus according to the present invention has the advantage that the position of the idle roller can be changed by the rotation and linear motion of the idle roller, and thus, the PET film roll feeding path can be automatically formed.

[0031] In addition, the electrode sheet rewinding apparatus according to the present invention has the advantage that a PET film roll feeding path can be automatically formed, and therefore, a decrease in work efficiency and generation of foreign matter due to movement of workers can be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a front view schematically showing an electrode sheet rewinding apparatus according to an embodiment of the present invention.

[0033] Figure 2 is a perspective view of an idle roller unit according to an embodiment of the present invention.

[0034] Figure 3 and Figure 4 is a schematic diagram illustrating a process of automatically connecting a PET film to an electrode sheet rewinding apparatus using an idle roller unit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In the present application, it should be understood that the terms "includes", "has", "comprising", etc. specify the presence of stated features, numbers, steps, operations, elements, components, or a combination thereof, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, or a combination thereof.

[0036] In addition, the same reference numerals are used throughout the drawings to represent components that perform similar functions or operations. In the case where a part is said to be connected to another part in the specification, not only can a part be directly connected to another part, but a part can also be indirectly connected to another part via other parts. In addition, including a certain element does not mean excluding other elements, but means that these elements can be further included unless otherwise specified.

[0037] Hereinafter, an electrode sheet rewinding apparatus according to the present invention will be described with reference to the accompanying drawings.

[0038] Figure 1 is a front view schematically showing an electrode sheet rewinding apparatus according to an embodiment of the present invention.

[0039] When referring to Figure 1 Describing the electrode sheet rewinding apparatus 1000 according to the present invention in detail, the electrode sheet rewinding apparatus 1000 includes an idle roller unit 100 , a bobbin 200 , a bobbin holder 300 , a bottom plate 400 , a vertical plate 500 , a contact roller 510 , and a PET film sensor 600 .

[0040] First, before the electrode sheet is rewound on the bobbin, a predetermined length of the PET film P is wound on the bobbin 200 in a state where the bobbin 200 is empty.

[0041] As described above, the PET film P is provided in order to use the entire electrode sheet without waste when unwinding the electrode sheet wound on the bobbin.

[0042] Next, the bobbin holder 300 is positioned on the bottom plate 400 to hold the bobbin 200 .

[0043] In addition, the vertical plate 500 is located on the bottom plate 400 , and the vertical plate 500 stands upright in a vertical direction in a state of being spaced apart from the bobbin holder 300 by a predetermined distance.

[0044] The contact roller 510 may be connected to one side of the vertical plate 500 .

[0045] The contact roller 510 configured in a roller shape presses the electrode sheet rewound around the bobbin 200 over the bobbin 200 to prevent the electrode sheet from being bent and to prevent air from being introduced between layers of the electrode sheet.

[0046] Meanwhile, the PET film sensor 600 is connected to the bottom plate 400 or the bobbin holder 300 to sense the position of the PET film P unwound from the bobbin 200 , thereby providing data required to set the moving range of the idle roller unit 100 .

[0047] A laser sensor, an ultrasonic sensor, or an optical sensor may be used as the PET film sensor 600. However, the present invention is not limited thereto, and any one of various known sensors capable of detecting the PET film P may be used.

[0048] Figure 2 is a perspective view of an idle roller unit according to an embodiment of the present invention.

[0049] When referring to Figure 2 Describing the position-variable idle roller unit 100 according to the present invention in detail, the idle roller unit 100 includes an idle roller 110 , a first driving device 120 , an upper frame 130 , a second driving device 140 , a lower frame 150 , and a guide roller 160 .

[0050] First, the idle roller 110 contacts the PET film P or the electrode sheet together with the contact roller 510 to maintain the tension of the PET film P or the electrode sheet and forms the PET film or the electrode sheet into a tangent line of the contact roller 510 so that the electrode sheet can be easily rewound. The idle roller 110 is a roller having a width greater than that of the electrode sheet or the PET film P.

[0051] Next, the first driving device 120 includes a driving shaft 121 , a first gear 122 , and an idle roller support 123 .

[0052] Here, the idle roller support 123 is connected to the opposite end of the driving shaft 121, and the driving shaft 121 extends through the first gear 122. When the first gear 122 rotates, the driving shaft 121 rotates together with the first gear 122 to turn the idle roller support 123 connected thereto from a position perpendicular to the floor to a position parallel to the floor, or from a position parallel to the floor to a position perpendicular to the floor.

[0053] In addition, one end of the idle roller support 123 is connected to the driving shaft 121, and the other end is connected to the idle roller 110. Therefore, the idle roller 110 also rotates with the rotation of the idle roller support 123, thereby changing the position of the idle roller 110.

[0054] Meanwhile, the upper frame 130 includes an upper frame body 131 and a second gear 132 .

[0055] The first driving device 120 is fixed on the upper frame body 131 , and the second gear 132 is engaged with the first gear 122 of the first driving device 120 to drive the first gear 122 .

[0056] The transmission ratio between the first gear 122 and the second gear 132 and the rotation speed of the second gear 132 may be appropriately adjusted to control the position change speed of the idle roller 110 .

[0057] Next, the second driving device 140 is located below the upper frame 130 .

[0058] The second driving device 140 is configured to linearly move the upper frame 130 in a direction parallel to the floor, and the second driving device 140 may be a combination of a linear motion (LM) guide and a motor. However, the present invention is not limited thereto, and any of various known devices capable of performing linear reciprocating motion may be used.

[0059] The upper frame 130 linearly reciprocates by the second driving device 140 , and thus the first driving device 120 connected to the upper frame 130 and the idle roller 110 connected to the first driving device 120 may linearly reciprocate.

[0060] Meanwhile, the lower frame 150 is connected to the bottom plate 400, and the second driving device 140 is disposed on the lower frame 150. The lower frame 150 is used to fix and support the idle roller unit 100.

[0061] In addition, a guide roller 160 may be connected to one side of the lower frame 150 .

[0062] The guide roller 160 is a roller for maintaining the tension of the electrode sheet together with the idle roller 110 .

[0063] Figure 3 and Figure 4 is a schematic diagram illustrating a process of automatically connecting a PET film to an electrode sheet rewinding apparatus using an idle roller unit according to an embodiment of the present invention.

[0064] When referring to Figure 3 and 4 Describing the process of automatically connecting the PET film P to the electrode sheet rewinding apparatus to form a roll feeding path for rewinding the electrode sheet, first, the bobbin 200 on which only the PET film P is wound is mounted to the electrode sheet rewinding apparatus 1000 .

[0065] Then, if Figure 3 As shown in (a), the position of the PET film P is sensed by the PET film sensor 600, and the first driving device 120 is driven based on the sensed data to rotate the idle roller 110 to be located below the PET film P.

[0066] Then, if Figure 3 As shown in (b), the second driving device 140 is used to linearly move the idle roller 110 in a direction parallel to the floor so as to accurately adjust the position of the idle roller 110.

[0067] Then, if Figure 4 As shown in (c), the PET film P is fully unfolded to a position below the idle roller 110, and then the idle roller 110 returns to its original position ( Figure 4 (d)), thereby forming a roller feeding path for the PET film P for rewinding the electrode sheet.

[0068] Although the specific details of the present invention have been described in detail, it will be appreciated by those skilled in the art that the detailed description only discloses the preferred embodiments of the present invention and therefore does not limit the scope of the present invention. Therefore, it will be appreciated by those skilled in the art that various changes and modifications are possible without departing from the category and technical ideas of the present invention, and it is apparent that these changes and modifications fall within the scope of the appended claims.

[0069] [Description of Reference Signs]

[0070] 1000: Electrode sheet rewinding equipment

[0071] 100: Idle roller unit

[0072] 110: Idle roller

[0073] 120: First drive device

[0074] 121: Drive shaft

[0075] 122: First Gear

[0076] 123: Idle roller support

[0077] 130: Upper frame

[0078] 131: Upper frame body

[0079] 132: Second gear

[0080] 140: Second drive device

Claims

1. An electrode sheet rewinding device (1000) for rewinding an electrode sheet, the electrode sheet having passed a part of a secondary battery electrode manufacturing process, the electrode sheet rewinding device (1000) comprising: a bobbin (200) on which a PET film (P) is wound; a bobbin holder (300) configured to hold the bobbin (200); a bottom plate (400) located below the bobbin holder (300) and configured to support the bobbin holder (300); a roller contact roller (510) configured to press the electrode sheet rewound around the bobbin (200) above the bobbin (200) to prevent the electrode sheet from bending; a vertical plate (500) located at one side of the bottom plate (400), the contact roller (510) being attached to the vertical plate (500); and An idle roller unit (100) is configured to form the electrode sheet rewound around the bobbin (200) into a tangent line of the contact roller (510) together with the contact roller (510), wherein The idle roller unit (100) comprises: an idle roller (110) configured to maintain the tension of the rewound electrode sheet and form the electrode sheet into a tangent line of the contact roller (510); as well as The first driving device (120) and the second driving device (140) are configured to change the position of the idle roller (110).

2. The electrode sheet rewinding apparatus (1000) according to claim 1, wherein the idle roller unit (100) further comprises a guide roller (160), wherein the guide roller is configured to maintain the tension of the electrode sheet together with the idle roller (110).

3. The electrode sheet rewinding device (1000) according to claim 2, wherein the idle roller unit (100) further includes an upper frame (130), the first driving device (120) is arranged above the upper frame, and the second driving device (140) is arranged below the upper frame.

4. The electrode sheet rewinding device (1000) according to claim 3, wherein the idle roller unit (100) further includes a lower frame (150) located below the second driving device (140), and the lower frame is configured to fix the idle roller unit (100) to the base plate (400).

5. The electrode sheet rewinding device (1000) according to claim 4, wherein the first driving device (120) comprises: A drive shaft (121); a first gear (122), the first gear (122) being connected to the driving shaft (121); as well as An idle roller support member (123) is rotatably connected to the drive shaft (121) on one side and connected to the idle roller (110) on the other side, thereby The first driving device causes the idle roller (110) to rotate from a position perpendicular to the floor to a position parallel to the floor.

6. The electrode sheet rewinding apparatus (1000) according to claim 5, wherein the upper frame (130) comprises a second gear (132) meshed with the first gear (122), the second gear being configured to rotate the first gear (122).

7. The electrode sheet rewinding device (1000) according to claim 4, wherein the second driving device (140) is located between the upper frame (130) and the lower frame (150) to move the idle roller (110) linearly in a direction parallel to the floor.

8. The electrode sheet rewinding device (1000) according to claim 1, further comprising a PET film sensor (600).

9. The electrode sheet rewinding apparatus (1000) according to claim 8, wherein the PET film sensor (600) is attached to the base plate (400) or the bobbin holder (300).

10. A battery cell comprising an electrode manufactured using the electrode sheet rewinding apparatus (1000) according to any one of claims 1 to 9. 11 . A battery module comprising the battery cell according to claim 10 .

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