Rolling rolls and electrode rolling apparatus including the same

Abstract

The present invention relates to a rolling roll and an electrode rolling device including the same. The rolling roll according to one embodiment of the present invention includes a rotating shaft, a pair of roll units mounted on the rotating shaft at a predetermined interval, and an induction heating roll disposed between the pair of roll units, mounted on the rotating shaft, and configured to be induction heated when the rotating shaft rotates, the induction heating roll including an induction coil and a main body surrounding the induction coil.

Description

Technical Field

[0001] The present invention relates to a rolling roll and an electrode rolling apparatus including the same, and more particularly, to a rolling roll and an electrode rolling apparatus capable of preventing wrinkles in a plain portion of an electrode sheet by providing heat to the plain portion in the rolling process of the electrode sheet.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0066839 filed on May 31, 2022, and all the contents disclosed in the document of the Korean patent application are incorporated herein by reference.

Background Art

[0003] As the application fields for secondary batteries expand, the demand for higher-capacity secondary batteries has been rapidly increasing. As a method for increasing the capacity of secondary batteries, research on technologies for increasing the loading amount of electrode active materials has been progressing. However, when the loading amount of the electrode active material is increased, the volume of the electrode increases. At this time, in order to reduce the volume of the electrode, a process of rolling the electrode at a higher pressure is required.

[0004] FIGS. 1 and 2 are diagrams for explaining the process of rolling an electrode sheet using a conventional rolling roll.

[0005] Referring to FIGS. 1 and 2, the electrode substrate 10 has a coating portion 12 coated with a positive or negative electrode active material and a plain portion 11 not coated with the electrode active material. The plain portion 11 is a portion not coated with the electrode active material.

[0006] Referring to FIG. 2, the coating portions 12 are provided linearly along the running direction MD of the electrode substrate 10, and a plurality of coating portions 12 may be provided along the width direction W of the electrode substrate 10, and the plain portion 11 is located between two adjacent coating portions 12.

[0007] The electrode substrate 10 undergoes a rolling process as it passes through a pair of rolling rollers 21 and 22. During this process, the rolling rollers 21 and 22 come into contact with the coating portion 12 and press against it. In this way, the density of the coating portion 12 of the electrode substrate 10 increases and its volume decreases during the rolling process.

[0008] However, there is a problem in that the plain portion 11 becomes severely wrinkled or breaks during the process of rolling the electrode substrate 10 under high pressure. [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention aims to provide a rolling roll capable of supplying heat to the plain areas of an electrode sheet during the electrode sheet rolling process to prevent wrinkles in those areas, and an electrode rolling apparatus including the same. [Means for solving the problem]

[0010] To solve the above-mentioned problems, a rolling roll according to one embodiment of the present invention includes a rotating shaft, a pair of roll sections mounted on the rotating shaft at a predetermined distance apart, and an induction heating roll disposed between the pair of roll sections, mounted on the rotating shaft, and provided to be induction heated when the rotating shaft rotates, including an induction coil and a body surrounding the induction coil.

[0011] Furthermore, the induction coil may be configured to generate heat when an alternating current is applied. The body of the induction heating roll may also have a heating roll surface that is heated by the heat transmitted from the induction coil. Heat can be transmitted to the outside through the heating roll surface.

[0012] Furthermore, the induction heating roll includes an iron core, and the induction coil is arranged to surround the iron core. One or more induction coils may be provided.

[0013] Furthermore, the induction coil is electrically connected to the power supply unit, and when an AC voltage is applied to the induction coil through the power supply unit, an alternating magnetic flux is generated, which in turn generates an induced current, and this induced current can cause the main body to heat up in Joules. In such a structure, the generated heat can be transmitted to the outside through the heating roll surface. Also, if the induction heating roll is located on the plain portion of the electrode sheet, heat can be transferred toward the plain portion of the electrode sheet during the rolling process, making it easier to perform forced stretching on the plain portion.

[0014] The pair of roll sections may include a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the workpiece to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the workpiece to be rolled. The induction heating roll is positioned between the first roll section and the second roll section. In this case, the first roll section contacts one surface of the induction heating roll, and the second roll section contacts the other surface of the induction heating roll.

[0015] The first roll portion may have a first inner surface that contacts the induction heating roll and a first outer surface opposite to the first inner surface. The first inner surface and the first outer surface may be arranged parallel to each other. In this case, the first roll surface connects the first inner surface and the first outer surface. The first inner surface may have the same diameter as the induction heating roll. In such a structure, the heating roll surface of the induction heating roll and the first roll surface of the first roll portion can be connected without any steps.

[0016] Furthermore, the first roll portion may be provided with a diameter of the first outer surface smaller than the diameter of the first inner surface.

[0017] In one embodiment, the first roll portion may have a frustoconical shape in which the cross-sectional diameter of the first roll surface decreases from the first inner surface to the first outer surface.

[0018] Furthermore, the radius of the first inner surface of the first roll portion may be set to be larger than the radius of the first outer surface by a range of 0.3 mm to 0.5 mm.

[0019] Furthermore, the first roll portion may include a first core portion coupled to the rotation shaft and a first surface portion surrounding the first core portion and having a thermal conductivity lower than that of the first core portion.

[0020] Furthermore, the second roll portion may have a second inner surface that contacts the induction heating roll and a second outer surface opposite to the second inner surface. The second inner surface may have the same diameter as the induction heating roll. The second inner surface and the second outer surface may be arranged parallel to each other. In this case, the second roll surface can connect the second inner surface and the second outer surface. In such a structure, the heating roll surface of the induction heating roll and the second roll surface of the second roll portion can be connected without any steps.

[0021] Furthermore, the second roll portion may be provided with a diameter of the second outer surface smaller than the diameter of the second inner surface.

[0022] In one embodiment, the second roll portion may have a frustoconical shape in which the cross-sectional diameter of the second roll surface decreases from the second inner surface to the second outer surface.

[0023] Furthermore, the radius of the second inner surface of the second roll portion may be set to be 0.3 mm to 0.5 mm larger than the radius of the second outer surface.

[0024] Furthermore, the second roll portion may include a second core portion coupled to the rotation shaft and a second surface portion surrounding the second core portion and having a thermal conductivity lower than that of the second core portion.

[0025] Furthermore, the pair of roll sections may be arranged symmetrically with respect to the induction heating roll.

[0026] In addition, an electrode rolling device according to an embodiment of the present invention is disposed on a running path of an electrode sheet provided with a coating portion and a non-coated portion, and includes a pair of rolling rolls that press the electrode sheet vertically and a control unit that controls the operation of each rolling roll.

[0027] Each rolling roll includes a rotating shaft, a pair of roll portions that are mounted on the rotating shaft at a predetermined interval and are respectively located on the coating portion of the electrode sheet, and an induction heating roll that is disposed between the pair of roll portions, is mounted on the rotating shaft, is located on the non-coated portion of the electrode sheet, and is provided so as to be induction-heated when the rotating shaft rotates, and includes a main body that surrounds the induction coil.

[0028] In addition, the induction coil is provided so as to generate heat when an alternating current is applied, and the main body of the induction heating roll is heated by the heat transmitted from the induction coil and has a heating roll surface disposed to face the non-coated portion.

[0029] In addition, the pair of roll portions can each include a first roll portion that is disposed on one side of the induction heating roll and has a first roll surface that contacts the rolling object, and a second roll portion that is disposed on the other side of the induction heating roll and has a second roll surface that contacts the rolling object.

[0030] In addition, the first roll portion contacts the induction heating roll and has a first inner surface having the same diameter as the diameter of the induction heating roll and a first outer surface in a direction opposite to the first inner surface, and the first roll surface connects the first inner surface and the first outer surface.

[0031] In addition, the second roll portion contacts the induction heating roll and has a second inner surface having the same diameter as the diameter of the induction heating roll and a second outer surface in a direction opposite to the second inner surface, and the second roll surface connects the second inner surface and the second outer surface.

[0032] Furthermore, the first roll portion is provided such that the diameter of the first outer surface is smaller than the diameter of the first inner surface, and the second roll portion is provided such that the diameter of the second outer surface is smaller than the diameter of the second inner surface.

[0033] Furthermore, the first roll portion may include a first core portion coupled to the rotation shaft and a first surface portion surrounding the first core portion and having a thermal conductivity lower than that of the first core portion.

[0034] Furthermore, the second roll portion may include a second core portion coupled to the rotation shaft and a second surface portion surrounding the second core portion and having a thermal conductivity lower than that of the second core portion. [Effects of the Invention]

[0035] As described above, according to at least one embodiment of the present invention, when the rolling roll applies pressure to the coated portion of the electrode sheet, heat is supplied to the plain portion of the electrode sheet, thereby forcibly stretching the plain portion and preventing wrinkles in the plain portion during the electrode sheet rolling process. [Brief explanation of the drawing]

[0036] [Figure 1] This diagram illustrates the process of rolling an electrode sheet using conventional rolling rolls. [Figure 2] This diagram illustrates the process of rolling an electrode sheet using conventional rolling rolls. [Figure 3] This figure illustrates the process of rolling an electrode sheet using a rolling roll according to one embodiment of the present invention. [Figure 4] This figure illustrates the process of rolling an electrode sheet using a rolling roll according to one embodiment of the present invention. [Figure 5] This is a cross-sectional view of a rolling roll according to one embodiment of the present invention. [Figure 6] This is a diagram illustrating the structure of a rolling roll according to one embodiment of the present invention. [Modes for carrying out the invention]

[0037] Hereinafter, a rolling roll and an electrode rolling apparatus including the same according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

[0038] Furthermore, regardless of the drawing reference numerals, identical or corresponding components are assigned the same or similar reference numerals, and redundant explanations are omitted. For the sake of clarity, the size and shape of each component shown may be exaggerated or reduced.

[0039] Figures 3 and 4 are diagrams illustrating the process of rolling an electrode sheet using a rolling roll according to one embodiment of the present invention, Figure 5 is a cross-sectional view of a rolling roll according to one embodiment of the present invention, and Figure 6 is a diagram illustrating the structure of a rolling roll according to one embodiment of the present invention.

[0040] Referring to Figures 3 and 4, an electrode rolling mill 100 according to one embodiment of the present invention includes a pair of rolling rolls 110 and 120 and a control unit 130. The control unit 130 controls the operation of each of the rolling rolls 110 and 120.

[0041] Each rolling roll 110, 120 includes a rotating shaft 111 and a pair of roll sections 115, 117 mounted on the rotating shaft 111 at a predetermined distance apart and positioned on the coated portion 12 of the electrode sheet 10, respectively. Each rolling roll 110, 120 also includes an induction heating roll 113 positioned between the pair of roll sections 115, 117 and mounted on the rotating shaft 111.

[0042] The induction heating roll 113 includes an induction coil 113b positioned on the plain portion 11 of the electrode sheet 10 and provided to be induction heated when the rotating shaft 111 rotates, and a main body 113a surrounding the induction coil 113b.

[0043] A pair of rolling rolls 110 and 120 are positioned along the travel path MD of the electrode sheet 10, above and below the electrode sheet 10. The pair of rolling rolls 110 and 120 are positioned to press the electrode sheet 10 from above and below.

[0044] The electrode rolling apparatus 100 may include a power supply unit 150 electrically connected to the induction coil 113b and a drive unit 140 (e.g., a motor) for rotating the rotation shafts 111 of the rolling rolls 110 and 120. The power supply unit 150 and the drive unit 140 may be controlled by a control unit 130.

[0045] As described with reference to Figures 1 and 2, the electrode sheet 10 has a coated portion 12 and a plain portion 11. The induction heating roll 113 is positioned on the plain portion 11 of the electrode sheet 10 to transfer heat to the plain portion 11 of the electrode sheet 10.

[0046] The induction coil 113b is electrically connected to the power supply unit 150. When an AC voltage is applied to the induction coil 113b through the power supply unit 150, an induced current is generated, and this induced current can cause the main body 113a to generate Joule heat. Furthermore, when the induction heating roll 113 is positioned on the plain portion 11 of the electrode sheet 10, the induction heating roll 113 transfers heat to the plain portion 11 of the electrode sheet 10 during the process in which the pair of rolls roll the coated portion 12, making it easier to perform forced stretching on the plain portion 11.

[0047] Furthermore, the pair of rolling rolls 110 and 120 rotate in opposite directions to pressurize and roll the electrode sheet 10.

[0048] The pair of rolling rolls 110 and 120 have the same structure and operating method. In this embodiment, for the sake of explanation, the description will focus on the rolling roll 110, which is located at the top, with reference to Figure 3.

[0049] A rolling roll 110 according to one embodiment of the present invention includes a rotating shaft 111, an induction heating roll 113, and a pair of roll sections 115 and 117.

[0050] Referring to Figures 4 and 5, the rolling rolls 110 and 120 include a rotating shaft 111 and a pair of roll sections 115 and 117 mounted on the rotating shaft 111 at a predetermined distance apart and positioned on the coating portion 12 of the electrode sheet 10, respectively. Each rolling roll 110 and 120 also includes an induction heating roll 113 positioned between the pair of roll sections 115 and 117 and mounted on the rotating shaft 111.

[0051] The induction heating roll 113 includes an induction coil 113b positioned on the plain portion 11 of the electrode sheet 10 and provided to be induction heated when the rotating shaft 111 rotates, and a main body 113a surrounding the induction coil 113b.

[0052] The rotating shaft 111 is provided along the width direction w of the electrode sheet 10. The rotation direction and rotation speed of the rotating shaft 111 can be controlled by the control unit 130.

[0053] The induction heating roll 113 is mounted on the rotating shaft 111 so as to be positioned opposite the plain portion 11 of the electrode sheet 10, and transfers heat to the plain portion 11 while being induction heated as the rotating shaft 111 rotates. For example, if the plain portion 11 is located in the center of the electrode sheet 10 in the width direction w, the induction heating roll 113 can be mounted in the center of the rotating shaft 111. During the rolling process, the control unit 130 can rotate the rolling roll 110 through the drive unit 140 and apply alternating current to the induction coil 113b through the power supply unit 150.

[0054] The induction heating roll 113 includes a main body 113a mounted on a rotating shaft 111 and an induction coil 113b positioned inside the main body 113a.

[0055] Furthermore, the induction coil 113b is provided to generate heat when an alternating current is applied, and the body 113a of the induction heating roll 113 has a heating roll surface 113a-1 that is heated by the heat transmitted from the induction coil 113b.

[0056] Referring to Figures 5 and 6, the main body 113a is mounted on the rotating shaft 111 so as to surround the induction coil 113b. The main body 113a has a roll width Wr corresponding to the width of the plain section 11 and has a heated roll surface 113a-1 that is heated by the heat transmitted from the induction coil 113b.

[0057] Furthermore, the main body 113a has a diameter larger than the diameter of the rotating shaft 111. The main body 113a has a cylindrical shape with a circular cross-section. The main body 113a is mounted on the rotating shaft 111 so as to surround the central part of the rotating shaft 111. As an example, the main body 113a may be made of stainless steel.

[0058] Furthermore, the induction coil 113b is built into the main body 113a and generates heat while creating a magnetic field when an alternating current is applied. The heat generated by the induction coil 113b heats the main body 113a to a predetermined temperature. Heat is also transferred to the outside of the main body (plain part) via the heating roll surface 113a-1.

[0059] In the rolling process of the electrode sheet 10, the induction heating roll 113 is positioned opposite the plain portion 11, and heat is transferred to the plain portion 11, causing the plain portion 11 to be forcibly stretched, thereby preventing wrinkles in the plain portion 11.

[0060] A pair of roll sections 115 and 117 are provided on both sides of the induction heating roll 113. The pair of roll sections 115 and 117 are mounted on the rotating shaft 111 and pressurize and roll the electrode sheet 10 when the rotating shaft 111 rotates.

[0061] When the induction heating roll 113 is installed in the center of the rotating shaft 111, the pair of roll sections 115 and 117 are mounted on the rotating shaft 111, flanking the induction heating roll 113. In this embodiment, for the sake of explanation, the pair of roll sections are referred to as the first roll section 115 and the second roll section 117, according to their installation positions.

[0062] The pair of roll sections 115 and 117 include a first roll section 115, which is positioned on one side of the induction heating roll 113 and has a first roll surface that contacts the object to be rolled (the coated portion of the electrode sheet), and a second roll section 117, which is positioned on the other side of the induction heating roll 113 and has a second roll surface that contacts the object to be rolled (the coated portion of the electrode sheet).

[0063] Referring to Figures 3 and 4, the electrode rolling apparatus 100 can perform the rolling process of the two coated sections 12 through a pair of roll sections 115 and 117, and can apply heat to the plain section 11 located between the two coated sections 12 through an induction heating roll 113.

[0064] Referring to Figures 5 and 6, the first roll section 115 can be mounted on the rotating shaft 111 on one side of the induction heating roll 113. The first roll section 115 can be mounted on the rotating shaft 111 so as to be detachable from the induction heating roll 113.

[0065] The first roll section 115 has a first roll surface 115c-3 that pressurizes and rolls the coating section 12 when the rotating shaft 111 rotates, and the first roll surface 115c-3 can be connected to the heated roll surface 113a-1 without any step difference.

[0066] Furthermore, the first roll portion 115 includes a first core portion 115a and a first surface portion 115b. Specifically, the first roll portion 115 may include a first core portion 115a coupled to the rotation shaft 111, and a first surface portion 115b surrounding the first core portion 115a and having a thermal conductivity lower than that of the first core portion 115a.

[0067] Furthermore, the first core portion 115a may have a frustoconical structure. The first core portion 115a is mounted on the rotating shaft 111, and the first core portion 115a may be made of stainless steel.

[0068] Furthermore, the first surface portion 115b is provided so as to surround the first core portion 115a and has a different thermal conductivity than the first core portion 115a. The first surface portion 115b may be formed on the surface of the first core portion 115a using a material having a lower thermal conductivity than that of the first core portion 115a.

[0069] Referring to Figure 6, the first roll portion 115 is in contact with the induction heating roll 113 and has a first inner surface 115c-1 having the same diameter as the induction heating roll 113 and a first outer surface 115c-2 facing the opposite direction from the first inner surface 115c-1, and the first roll surface 115c-3 connects the first inner surface 115c-1 and the first outer surface 115c-2.

[0070] The first roll section 115 has a frustoconical shape with a first inner surface 115c-1, a first outer surface 115c-2, and a first roll surface 115c-3. Here, the first inner surface 115c-1 is the surface that contacts one surface of the induction heating roll 113.

[0071] The first outer surface 115c-2 has a smaller diameter than the first inner surface 115c-1 and is provided parallel to the first inner surface 115c-1. The first roll surface 115c-3 surrounds the rotation axis 111 and connects the first inner surface 115c-1 and the first outer surface 115c-2. The first roll surface 115c-3 is provided with a first surface portion 115b.

[0072] The first roll section 115 has a structure in which the cross-sectional diameter of the first roll surface 115c-3 decreases as you move from the first inner surface 115c-1 to the first outer surface 115c-2. The diameter of the first inner surface 115c-1 of the first roll section 115 may be set to be the same as the diameter of the induction heating roll 113.

[0073] Furthermore, the first roll portion 115 may be provided with a diameter (or radius) of the first outer surface smaller than the diameter (or radius) of the first inner surface.

[0074] The first roll section 115 is provided with a radius R1 on the first inner surface that is 0.3 mm to 0.5 mm larger than the radius R2 on the first outer surface. That is, the difference between the radius R1 of the first inner surface 115c-1 and the radius R2 of the first outer surface 115c-2 (R1-R2=t) is within the range of 0.3 mm to 0.5 mm.

[0075] Furthermore, the pair of roll sections 115 and 117 may be arranged symmetrically with respect to the induction heating roll 113. That is, the first and second roll sections 115 and 117 have a symmetrical configuration with respect to the induction heating roll 113.

[0076] The second roll section 117 is mounted on the rotating shaft 111 on the other side of the induction heating roll 113. The second roll section 117 can be mounted on the rotating shaft 111 so as to be separable from the induction heating roll 113. The second roll section 117 is mounted on the rotating shaft 111, separated from the first roll section 115 with the induction heating roll 113 in between. The second roll section 117 has a second roll surface 117c-3 that presses and rolls the coating section 12 when the rotating shaft 111 rotates. Furthermore, the second roll surface 117c-3 can be connected to the heating roll surface 113a-1 without any step difference.

[0077] Referring to Figures 5 and 6, the second roll portion 117 includes a second core portion 117a and a second surface portion 117b. Specifically, the second roll portion 117 may include a second core portion 117a coupled to the rotating shaft 111 and a second surface portion 117b surrounding the second core portion 117a and having a thermal conductivity lower than that of the second core portion 117a.

[0078] Furthermore, the second core portion 117a is provided in a frustoconical structure. The second core portion 117a is mounted on the rotating shaft 111, and the second core portion 117a may be formed from the same material as the first core portion 115a.

[0079] Furthermore, the second surface portion 117b is provided so as to surround the second core portion 117a and has a different thermal conductivity than the second core portion 117a. The second surface portion 117b may be formed on the surface of the second core portion 117a using a material having a lower thermal conductivity than that of the second core portion 117a.

[0080] Referring to Figure 6, the second roll portion 117 is in contact with the induction heating roll 113 and has a second inner surface 117c-1 having the same diameter as the induction heating roll and a second outer surface 117c-2 facing the opposite direction from the second inner surface 117c-1, and the second roll surface 117c-3 connects the second inner surface 117c-1 and the second outer surface 117c-2.

[0081] Furthermore, the second roll section 117 has a frustoconical shape with a second inner surface 117c-1, a second outer surface 117c-2, and a second roll surface 117c-3. Here, the second inner surface 117c-1 is the surface that contacts the other surface of the induction heating roll 113. The diameter of the second inner surface 117c-1 of the second roll section 117 may be set to be the same as the diameter of the induction heating roll 113.

[0082] The second outer surface 117c-2 has a diameter (or radius) smaller than the diameter of the second inner surface 117c-1 and is a surface provided parallel to the second inner surface 117c-1.

[0083] Furthermore, the second roll portion 117 may be provided with a diameter (or radius) of the second outer surface smaller than the diameter (or radius) of the second inner surface.

[0084] Furthermore, the second roll section 117 has a structure in which the cross-sectional diameter of the second roll surface 117c-3 decreases as you move from the second inner surface 117c-1 to the second outer surface 117c-2. The second roll surface 117c-3 surrounds the rotation axis 111 and is the surface that connects the second inner surface 117c-1 and the second outer surface 117c-2. The second roll surface 117c-3 is provided with a second surface portion 117b.

[0085] Furthermore, the radius R1 of the second inner surface of the second roll section is set to be larger than the radius R2 of the second outer surface by 0.3 mm to 0.5 mm. That is, the difference between the radius R1 of the second inner surface 117c-1 and the radius R2 of the second outer surface 117c-2 (R1-R2=t) is in the range of 0.3 mm to 0.5 mm.

[0086] As described above, by including a pair of roll sections 115 and 117 for pressurizing and rolling the coated portion 12 of the electrode sheet 10, and an induction heating roll 113 for supplying heat to the plain portion 11, it is possible to supply heat to the plain portion 11 during the rolling process of the electrode sheet 10 and prevent wrinkles in the plain portion 11.

[0087] The embodiment described above is disclosed for illustrative purposes only, and a person skilled in the art with ordinary skill to the present invention will know that various modifications, alterations, and additions are possible within the spirit and scope of the invention, and such modifications, alterations, and additions should be considered to fall within the scope of the appended claims. [Industrial applicability]

[0088] According to at least one embodiment of the present invention, a rolling roll and an electrode rolling apparatus including the same, when the rolling roll applies pressure to the coated portion of the electrode sheet, heat is supplied to the plain portion of the electrode sheet, thereby forcibly stretching the plain portion and preventing wrinkles in the plain portion during the electrode sheet rolling process.

Claims

1. The axis of rotation and A pair of roll sections mounted on the aforementioned rotating shaft at predetermined intervals, An induction heating roll including an induction coil positioned between the pair of roll sections, mounted on the rotating shaft, and provided to be induction heated when the rotating shaft rotates, and a body surrounding the induction coil, The pair of roll sections includes a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the object to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the object to be rolled. The first roll portion is in contact with the induction heating roll and has a first inner surface having the same diameter as the induction heating roll and a first outer surface facing the opposite direction from the first inner surface. The first roll surface is a rolling roll connecting the first inner surface and the first outer surface.

2. The induction coil is provided to generate heat when an alternating current is applied. The rolling roll according to claim 1, wherein the body of the induction heating roll has a heating roll surface that is heated by heat transmitted from the induction coil.

3. The rolling roll according to claim 1, wherein the diameter of the first outer surface of the first roll portion is smaller than the diameter of the first inner surface.

4. A rotating shaft and, A pair of roll sections mounted on the aforementioned rotating shaft at predetermined intervals, An induction heating roll including an induction coil positioned between the pair of roll sections, mounted on the rotating shaft, and provided to be induction heated when the rotating shaft rotates, and a body surrounding the induction coil, The pair of roll sections includes a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the object to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the object to be rolled. The first roll portion includes a first core portion coupled to the rotating shaft and a first surface portion surrounding the first core portion and having a thermal conductivity lower than that of the first core portion.

5. A rotating shaft and, A pair of roll sections mounted on the aforementioned rotating shaft at predetermined intervals, An induction heating roll including an induction coil positioned between the pair of roll sections, mounted on the rotating shaft, and provided to be induction heated when the rotating shaft rotates, and a body surrounding the induction coil, The pair of roll sections includes a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the object to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the object to be rolled. The second roll portion is in contact with the induction heating roll and has a second inner surface having the same diameter as the induction heating roll and a second outer surface facing the opposite direction from the second inner surface. The second roll surface is a rolling roll connecting the second inner surface and the second outer surface.

6. The rolling roll according to claim 5, wherein the diameter of the second outer surface of the second roll portion is smaller than the diameter of the second inner surface.

7. A rotating shaft and A pair of roll sections mounted on the aforementioned rotating shaft at predetermined intervals, An induction heating roll including an induction coil positioned between the pair of roll sections, mounted on the rotating shaft, and provided to be induction heated when the rotating shaft rotates, and a body surrounding the induction coil, The pair of roll sections includes a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the object to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the object to be rolled. The rolling roll comprises a second core portion coupled to the rotating shaft and a second surface portion surrounding the second core portion and having a thermal conductivity lower than that of the second core portion.

8. The rolling roll according to claim 1, wherein the pair of roll sections are arranged symmetrically with respect to the induction heating roll.

9. A pair of rolling rolls are arranged in the path of an electrode sheet having a coated portion and a plain portion, and press the electrode sheet up and down. Includes a control unit that controls the operation of each rolling roll, Each rolling roll is The axis of rotation and A pair of roll sections are mounted on the aforementioned rotating shaft at predetermined intervals and are positioned on the coating of the electrode sheet, The induction heating roll includes an induction coil positioned between the pair of roll sections, mounted on the rotating shaft, located on the plain portion of the electrode sheet, and provided to be induction heated when the rotating shaft rotates, and a body surrounding the induction coil, The pair of roll sections includes a first roll section positioned on one side of the induction heating roll and having a first roll surface that contacts the object to be rolled, and a second roll section positioned on the other side of the induction heating roll and having a second roll surface that contacts the object to be rolled. The first roll portion is in contact with the induction heating roll and has a first inner surface having the same diameter as the induction heating roll and a first outer surface facing the opposite direction from the first inner surface. The first roll surface connects the first inner surface and the first outer surface, The second roll portion is in contact with the induction heating roll and has a second inner surface having the same diameter as the induction heating roll and a second outer surface facing the opposite direction from the second inner surface. The second roll surface connects the second inner surface and the second outer surface in an electrode rolling apparatus.

10. The induction coil is provided to generate heat when an alternating current is applied. The electrode rolling apparatus according to claim 9, wherein the body of the induction heating roll is heated by heat transmitted from the induction coil and has a heating roll surface that is positioned opposite to the plain portion.

11. The diameter of the first outer surface of the first roll portion is smaller than the diameter of the first inner surface. The electrode rolling apparatus according to claim 9, wherein the diameter of the second outer surface of the second roll portion is smaller than the diameter of the second inner surface.

12. The first roll portion includes a first core portion coupled to the rotation shaft, and a first surface portion surrounding the first core portion and having a thermal conductivity lower than that of the first core portion. The electrode rolling apparatus according to claim 9, wherein the second roll portion includes a second core portion coupled to the rotating shaft and a second surface portion surrounding the second core portion and having a thermal conductivity lower than that of the second core portion.

Images