Knife and secondary battery manufacturing apparatus including the same

Abstract

The knife according to an embodiment of the present invention includes a blade, a first surface and a second surface that extend with a predetermined angle in a first direction which is a cutting direction, and a third surface that extends in a second direction perpendicular to the first direction. One end of the first surface and one end of the second surface are in contact with each other to form a vertex which is the blade, and one end and the other end of the third surface are in contact with the other end of the first surface and the other end of the second surface, respectively.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0105363 filed on August 23, 2022, Korean Patent Application No. 10 - 2023 - 0102321 filed on August 4, 2023, and Korean Patent Application No. 10 - 2023 - 0102322 filed on August 4, 2023, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a secondary battery manufacturing apparatus, and more specifically, to a battery cell manufacturing apparatus capable of shortening the pouch sealing time and ensuring the sealing quality of battery cells.

Background Art

[0003] As the technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source has been rapidly increasing. Therefore, many studies on secondary batteries that can meet various requirements have been conducted.

[0004] Secondary batteries have attracted much attention not only as an energy source for mobile devices such as mobile phones, digital cameras, and notebook computers, but also as an energy source for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0005] Typically, there is a high demand for lithium secondary batteries such as lithium - ion batteries and lithium - ion polymer batteries, which have advantages such as high energy density, discharge voltage, and output stability.

[0006] In addition, secondary batteries may also be classified according to the structure of the electrode assembly in which a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode are laminated. Typically, there are a jelly roll (winding type) electrode assembly having a structure in which a long sheet-type positive electrode and negative electrode are wound with a separator interposed therebetween, a stack type (lamination type) electrode assembly in which a plurality of positive electrodes and negative electrodes cut out in units of a predetermined size are sequentially laminated with a separator interposed therebetween, and the like. Among these, in order to manufacture a stack type (lamination type) electrode assembly, it is necessary to cut a priority sheet-type positive electrode and negative electrode.

[0007] FIG. 1 is a diagram showing a conventional secondary battery manufacturing apparatus. FIG. 2 is a drawing showing that a secondary battery material is baked when a sheet is cut by a conventional secondary battery manufacturing apparatus.

[0008] Referring to FIGS. 1 and 2, a conventional secondary battery manufacturing apparatus 10 can cut a sheet 11 with a cutting member 20. The sheet 11 may include an electrode sheet or a separator sheet.

[0009] Specifically, the cutting member 20 can cut the sheet 11 that moves in the second direction (x-axis direction) while moving in the first direction (z-axis direction and -z-axis direction).

[0010] However, when the sheet 11 is repeatedly cut, heat is generated on the cutting member 20 due to friction or the like, and scattered matter of the cut sheet 11 may be baked. More specifically, the scattered matter or the like rides up in the direction of the blade inclined surface in a state of being in contact with the blade of the cutting member 20 and is baked. Therefore, the cut surface of the cut sheet 11 may not be smooth due to scattered matter of the sheet baked on the cutting member 20.

[0011] Also, when the electrode sheet 11 is repeatedly cut, the blade of the cutting member 20 may become dull. When the electrode sheet 11 is cut with the cutting member 20 having a dull blade, the cut surfaces of the cut electrodes or the separation membrane 12 may not be smooth.

[0012] Therefore, there is a problem that there is a possibility of occurrence of poor quality of the electrode due to the adhesion of sheet debris or the like to the cutting member 20 or the dulling of the blade of the cutting member 20, and attempts have been continued to reduce the occurrence of such problems.

Summary of the Invention

Problems to be Solved by the Invention

[0013] The problem to be solved by the present invention is to provide a secondary battery manufacturing apparatus for manufacturing a secondary battery with improved efficiency in the secondary battery manufacturing process and improved safety.

[0014] However, the problems to be solved by the embodiments of the present invention are not limited to the above-described problems, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0015] A knife according to an embodiment of the present invention includes a blade, and a first surface and a second surface that extend with a predetermined angle in a first direction that is a cutting direction, and a third surface that extends in a second direction perpendicular to the first direction. One end portion of the first surface and one end portion of the second surface are in contact with each other to form a vertex that is the blade, and one end portion and the other end portion of the third surface are in contact with the other end portion of the first surface and the other end portion of the second surface, respectively.

[0016] The first surface and the second surface may be provided with a protruding portion that is a protruding region.

[0017] The protruding portion includes a protrusion start portion which is a region where the protruding portion starts with reference to the vertex, and the length from the vertex to the protrusion start portion may be shorter than the height of the sheet.

[0018] In the knife according to another embodiment of the present invention, it may include a recess which is a region recessed from the first surface and the second surface.

[0019] The recess includes a recess start portion which is a region where the recess starts with reference to the vertex, and the length from the vertex to the recess start portion may be shorter than the height of the sheet.

[0020] The radius of the recess may be 0.01 mm or more.

[0021] The knife may include a protruding portion which is a region protruding from the first surface and the second surface, and a recess which is a region recessed from the first surface and the second surface.

[0022] The angle of the vertex may be a blade of 120 degrees or less.

[0023] The knife may be cermet.

[0024] A secondary battery manufacturing apparatus according to still another embodiment of the present invention includes the knife.

Advantages of the Invention

[0025] According to the embodiment, since scattered materials generated during cutting of the secondary battery material do not adhere to the cutting member, the quality of the electrode can be improved and the safety of the secondary battery can be improved.

[0026] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned should be clearly understood by those skilled in the art from the description of the claims.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0028] Hereinafter, with reference to the accompanying drawings, it will be described in detail so that a person having ordinary knowledge in the technical field to which the present invention belongs can easily implement various embodiments of the present invention. The present invention can be embodied in various different forms and is not limited to the embodiments described here.

[0029] In order to clearly explain the present invention, parts that are unnecessary for the explanation are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

[0030] In addition, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for convenience of explanation, and thus the present invention is not necessarily limited to those shown. The thicknesses are enlarged to clearly represent various layers and regions in the drawings. And, in the drawings, for convenience of explanation, the thicknesses of some layers and regions are exaggeratedly shown.

[0031] In addition, when a part such as a layer, a film, a region, or a plate is "on" or "above" another part, this includes not only the case where it is "directly above" the other part but also the case where there are other parts in between. Conversely, when a part is "directly above" another part, it means that there are no other parts in between. Also, being "on" or "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "on" or "above" in the direction opposite to gravity.

[0032] In addition, throughout the specification, when a part "includes" a certain component, this means that other components can be further included, rather than excluding other components unless otherwise stated.

[0033] In addition, throughout the specification, when it is said "on a plane", this means when the target part is viewed from above, and when it is said "cross-sectional view", this means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0034] FIG. 3 is a perspective view showing a secondary battery manufacturing apparatus according to an embodiment of the present invention. FIG. 4 is a view of the cutting member and the vibrator of FIG. 3 of the present invention as viewed from the third direction.

[0035] Referring to FIG. 3, a secondary battery manufacturing apparatus 100 according to an embodiment of the present invention includes a substrate 130, a cutting member 200, and a vibrator 300.

[0036] The substrate 130 may be a flat plate. The sheet 110 may be located on one side of the substrate 130. The sheet 110 may contain secondary battery materials. As an example, the sheet 110 may be an electrode sheet or a separator sheet.

[0037] The substrate 130 can move in the second direction D2, and the sheet 110 can also move along with the movement of the substrate 130. Here, the second direction D2 may be a direction parallel to the substrate 130.

[0038] The cutting member 200 can contact the sheet 110 while moving in the first direction D1. The first direction D1 may be a direction perpendicular to the substrate 130. In this figure, the first direction D1 is shown as one direction in the coordinate system, but this includes not only one direction in the coordinate system but also the direction opposite thereto, and the same should be understood for the second direction D2 and the third direction D3.

[0039] The cutting member 200 can contact the sheet 110 and cut the sheet 110. At this time, the sheet 110 may be cut in the third direction D3.

[0040] The cutting member 200 can cut the sheet 110 using ultrasonic waves. Specifically, the cutting member 200 may be transmitted with ultrasonic waves generated from the vibrator 300. The vibrator 300 is in contact with and fixed to the cutting member 200 and can generate ultrasonic vibrations. That is, the ultrasonic vibrations generated from the vibrator 300 are transmitted to the cutting member 200, and the cutting member 200 can cut the sheet 110 by transmitting the transmitted ultrasonic vibrations to the sheet 110.

[0041] Hereinafter, the cutting member 200 and the vibrator 300 according to an embodiment of the present invention will be described in more detail with reference to FIG. 4.

[0042] Specifically, the cutting member 200 may include a knife 210, a support portion 220, and a clamp 230.

[0043] The knife 210 can cut the sheet 110. The knife 210 can cut the sheet 110 through ultrasonic vibration. The knife 210 can be provided with a blade at one end, and the blade can contact the sheet 110 to cut the sheet 110.

[0044] The knife 210 can be made of cermet. By configuring the knife 210 with cermet, the frictional force between the knife 210 and the secondary battery material during cutting can be minimized.

[0045] The knife 210 may include a first surface 211, a second surface 212, and a third surface 213.

[0046] The first surface 211 and the second surface 212 of the knife 210 may be surfaces that extend with a predetermined angle toward the first direction D1, respectively. Here, the first direction D1 is the direction in which the knife 210 moves and means the direction of cutting the sheet 110. At this time, one end of the first surface 211 and one end of the second surface 212 can form a vertex 214 while being in contact with each other, and the vertex 214 may be a blade.

[0047] One end of each of the first surface 211 and the second surface 212 can be in contact with each other to form a certain angle, and the angle can be defined as the first angle a1. That is, the angle at the vertex 214 may be the first angle a1. At this time, the first angle a1 may be 120 degrees or less.

[0048] Specifically, when the first angle a1 is 120 degrees or less, the cutting quality of the secondary battery material can be ensured. When the first angle a1 exceeds 120 degrees, cutting may not be properly performed due to problems such as the first surface 211 or the second surface 212 of the knife 210 contacting the sheet 110, which may affect the quality of the electrode.

[0049] The third surface 213 may be a surface extending in the second direction D2. Here, the second direction D2 is a direction perpendicular to the direction in which the knife 210 moves, and means a direction perpendicular to the first direction. One end and the other end of the third surface 213 may be in contact with and located at the other end of the first surface 211 and the other end of the second surface 212, respectively. The third surface 213 may be in contact with and fixed to one surface of the support portion 220. Therefore, the knife 210 may be attached and fixed to the support portion 220.

[0050] However, the shapes and directions of the first surface 211, the second surface 212, and the third surface 213 of the knife 210 are not limited to the contents described above, and any shape is possible as long as the quality of the electrode is maintained and the sheet 110 can be cut.

[0051] A clamp 230 may be provided on the outer surface of the support portion 220.

[0052] The clamp 230 may be provided to surround the outer surface of the support portion 220. That is, the clamp 230 can move while being coupled to the support portion 220. Specifically, the clamp 230 is connected to an actuator and can move in the first direction D1 by the control of the actuator. Therefore, the support portion 220 in contact with the clamp 230 and the knife 210 fixed to the support portion 220 can move in the first direction D1 corresponding to the movement of the clamp 230. That is, the knife 210 can cut the sheet 110 moving in the second direction D2 while moving in the first direction D1 by the clamp 230.

[0053] As described above, when cutting the sheet 110 using ultrasonic vibration, the cutting surface of the sheet 110 can be cut cleanly compared to cutting the sheet 110 with a general knife.

[0054] The vibrator 300 can generate ultrasonic vibrations and transmit the ultrasonic vibrations to the cutting member 200. Specifically, the ultrasonic vibrations generated by the vibrator 300 are transmitted to the support portion 220, and the ultrasonic vibrations transmitted to the support portion 220 are transmitted to the knife 210, whereby the sheet 110 can be cut.

[0055] The vibrator 300 may be fixedly positioned in contact with one surface of the support portion 220. Specifically, the vibrator 300 may be fixedly positioned in contact with one surface of the support portion 220 facing the one surface of the support portion 220 where the knife 210 is located.

[0056] The vibrator 300 can be transmitted a certain amount of power from an external power source and generate ultrasonic waves. However, when cutting the sheet 110, if the sheet 110 is not properly cut, such as when there are defects in the cutting quality, resonance may occur.

[0057] When resonance occurs, the power applied to the vibrator 300 may increase above a certain value, which also means that the cutting quality of the sheet 110 is poor.

[0058] In the above case, by the user / administrator recognizing the change in the power range applied to the vibrator 300, it can be confirmed that the cutting quality is poor. However, the secondary battery manufacturing apparatus 100 of the present invention can also include a secondary battery manufacturing system that recognizes the power value applied to the vibrator 300 and thereby determines whether the cutting quality of the sheet 110 is normal or poor. This will be described in more detail with reference to FIG. 5 hereinafter.

[0059] In summary, the user can determine the presence or absence of poor cutting quality of the sheet 110 through the change in the power range applied to the vibrator 300, or can also determine the presence or absence of poor cutting quality of the sheet 110 by providing a power sensor electrically connected to the power source and recognizing the power range applied to the vibrator 300.

[0060] Therefore, based on the power range applied to the vibrator 300, determining the cutting quality of the sheet can improve the accuracy of defective sorting, process efficiency, and the quality of the electrodes, compared to determining the cutting quality of the sheet using a camera, vision sensor, etc. as in the prior art.

[0061] Referring to FIG. 4 again, the support portion 220 and the vibrator 300 may each include a hole. The support portion 220 may include a first hole 221, and the vibrator 300 may include a second hole 310. The first hole 221 is a hole penetrating the support portion 220, and the second hole 310 is a hole penetrating the vibrator 300. Each of the first hole 221 and the second hole 310 may be at least one or more.

[0062] Specifically, although the first hole 221 is shown as penetrating the support portion 220 in the third direction D3, it is not limited thereto, and the first hole 221 may penetrate the support portion 220 in the second direction D2. Similarly to the first hole 221, although the second hole 310 is shown as penetrating the vibrator 300 in the third direction D3, it is not limited thereto, and the second hole 310 may penetrate the vibrator 300 in the second direction D2.

[0063] The first hole 221 and the second hole 310 can serve as flow paths. This is because a fluid such as air can move through the first hole 221 and the second hole 310. Therefore, when heat is generated in the cutting member 200 and the vibrator 300 due to the continuously performed cutting process, air cooling is performed by the first hole 221 and the second hole 310, and the heat generated in the cutting member 200 and the vibrator 300 can be cooled. By preventing the heat generated in the vibrator 300 from being transmitted to the support portion 220 and the knife 210, when cutting the sheet 110, it is possible to prevent the secondary battery material from sticking to the knife 210 due to heat as much as possible.

[0064] FIG. 5 is a flowchart showing the process of recognizing the presence or absence of defects in a secondary battery. FIG. 6(a) is a flowchart showing the process by which a user recognizes the presence or absence of defects in a secondary battery, and FIG. 6(b) is a flowchart showing the process by which a secondary battery manufacturing system recognizes the presence or absence of defects in a secondary battery.

[0065] Referring to FIGS. 5 and 6, in a secondary battery manufacturing apparatus 100 according to an embodiment of the present invention, it is possible to determine the presence or absence of defects in the sheet according to the power range applied to the vibrator 300.

[0066] Specifically, when the sheet is not properly cut by the secondary battery manufacturing apparatus 100, resonance may occur. When resonance occurs, the power applied to the vibrator 300 may be above a preset level. For example, if the power applied to the vibrator 300 during normal cutting is referred to as first power W1, when the cut sheet 110 is defective, the power applied to the vibrator 300 can be said to be second power W2. At this time, the first power W1 and the second power W2 may be different values.

[0067] Therefore, when the second power W2 is applied to the vibrator 300, the user or the secondary battery manufacturing system can recognize the abnormality in the power range and take corresponding measures. This will be described in more detail with reference to FIG. 6 in relation to recognizing such a power range.

[0068] Referring to FIG. 6(a), depending on the power range applied to the vibrator 300, the user or the administrator can take appropriate measures.

[0069] More specifically, the secondary battery manufacturing apparatus 100 according to an embodiment may include a display unit U1. The display unit U1 may be configured to be electrically connected to the power supply P and display the power range applied from the power supply P to the vibrator 300. The display unit U1 may include a configuration for displaying the power range, and may include a configuration such as a panel, for example. Therefore, through the display unit U1, the user can recognize the power range currently applied to the secondary battery manufacturing apparatus 100.

[0070] Therefore, when the power range displayed on the display unit U1 is the first power W1, the user can recognize that the secondary battery manufacturing apparatus 100 is operating normally and can continue to cause the secondary battery manufacturing apparatus 100 to cut the sheet 110.

[0071] On the other hand, when the power range displayed on the display unit U1 is the second power W2, the user can recognize that the current resonance occurs and the sheet 110 is not properly cut, and a defect has occurred, and can stop the secondary battery manufacturing process.

[0072] Referring to FIG. 6(b), the secondary battery manufacturing apparatus 100 according to another embodiment can be controlled by a secondary battery manufacturing system.

[0073] The secondary battery manufacturing system may include a sensor unit U2 and a control unit U3. Both the sensor unit U2 and the control unit U3 may be configured to be electrically connected to the power supply P.

[0074] The sensor unit U2 can recognize the power range applied to the vibrator 300 and transmit an electrical signal based on the range of the power value to the control unit U3. The control unit U3 can be transmitted an electrical signal from the sensor unit U2 and thereby control the operation of the secondary battery manufacturing apparatus 100. That is, the control unit U3 can control the operation of the cutting member based on the electrical signal transmitted from the sensor unit U2.

[0075] Specifically, when the power value applied to the vibrator 300 is the first power W1, the sensor unit U2 can recognize this and transmit the first electrical signal to the control unit U3. In this case, the control unit U3 can control the operation of the secondary battery manufacturing apparatus 100 without stopping it, so that normal operation can continue. That is, the control unit U3 can control the operation of the cutting member without stopping it, so that normal operation can continue.

[0076] On the other hand, when the power value applied to the vibrator 300 is the second power W2, the sensor unit U2 can recognize this and transmit the second electrical signal to the control unit U3. In this case, the control unit U3 can stop the operation of the secondary battery manufacturing apparatus 100. That is, the control unit U3 can stop the operation of the cutting member. Therefore, when the operation of the secondary battery manufacturing apparatus 100 is stopped by the control unit U3, the user or administrator can judge the presence or absence of sheet defects and take measures such as replacing the knife so that normal cutting can be performed again.

[0077] Briefly described, the sensor unit U2 recognizes the power range applied to the vibrator 300, and the control unit U3 can control the secondary battery manufacturing apparatus 100 according to the power range.

[0078] When the secondary battery manufacturing apparatus 100 is controlled by the secondary battery manufacturing system, the secondary battery manufacturing apparatus 100 is systematically controlled. Therefore, compared with the user directly recognizing the power range through the display unit U1 and thereby maintaining or stopping the operation of the secondary battery manufacturing apparatus 100, the convenience of the user and administrator can be achieved. Also, in the manufacturing process, since the user and administrator do not need to continuously monitor the power range, manufacturing costs such as labor costs can be reduced.

[0079] FIG. 7 is a diagram showing a knife according to a modified example of the present invention. FIG. 8 is a diagram showing the degree of sticking of the secondary battery material depending on the position where the protruding portion of FIG. 7 is provided. (a) of FIG. 8 is a diagram showing the degree of sticking of the secondary battery material when the first length is shorter than the second length, and (b) of FIG. 8 is a diagram showing the degree of sticking of the secondary battery material when the first length is longer than the second length.

[0080] The knives described with reference to FIGS. 7 and 8 are modified examples of an embodiment of the present invention disclosed in FIGS. 3 and 4, and detailed descriptions of the same configurations as those described above are omitted.

[0081] Referring to FIGS. 7 and 8, the knife 210 according to the modified example of the present invention may include a protruding portion 215.

[0082] The protruding portion 215 may be located on the side surface of the knife 210. Specifically, the protruding portion 215 may be located on the first surface 211 and the second surface 212 of the knife 210, respectively. The protruding portion 215 may be an area protruding from the first surface 211 and the second surface 212.

[0083] The protruding portion 215 may be a structure for allowing the secondary battery material to separate from the knife 210 within the shortest time after the knife 210 cuts the sheet 110. That is, when cutting the sheet 110 with the knife 210 including the protruding portion 215, the secondary battery material baked on the knife 210 can hit the protruding portion 215 and separate from the knife 210. Therefore, the contact time between the secondary battery material and the knife 210 can be shortened by the protruding portion 215. Therefore, even if the secondary battery material is baked on the knife 210 due to the frictional heat generated during cutting, the secondary battery material can ride along the first surface 211 and the second surface 212 of the knife 210 and not be baked, and can separate from the knife 210 as soon as possible.

[0084] More specifically, the secondary battery material can be separated from the knife 210 with reference to the protruding start portion 215a. The protruding start portion 215a means the region where the protruding portion 215 starts, with reference to the vertex 214 where the first surface 211 and the second surface 212 are in contact.

[0085] Referring to FIG. 8, the length from the vertex 214 to the protruding start portion 215a may be such that the first length is d1, and the height of the sheet 110 may be the second length d2. At this time, the first length d1 may be shorter than the second length d2.

[0086] Specifically, referring to FIG. 8(a), when the first length d1 is shorter than the second length d2, the protruding portion 215 may be located on the first surface 211 and the second surface 212 with a height lower than the second length d2. In this case, when cutting the sheet 110, even if the secondary battery material is burned onto the knife 210 due to frictional heat, the protruding portion 215 allows the burned secondary battery material to be separated from the knife 210 without climbing further onto the first surface 211 and the second surface 212.

[0087] On the other hand, referring to FIG. 8(b), when the first length d1 is longer than the second length d2, the protruding portion 215 may have a height higher than the second length d2 and be located on the first surface 211 and the second surface 212. In this case, when cutting the sheet 110, the secondary battery material may not separate after being burned onto the knife 210 due to frictional heat and may be burned onto the knife 210 to a certain height or more. Therefore, even though the protruding portion 215 is provided, there is a high possibility that the cutting quality of the sheet 110 will be defective.

[0088] That is, for such reasons, it is preferable that the first length d1 is shorter than the second length d2.

[0089] Regarding the knife 210 according to FIGS. 7 and 8, since the cutting load is concentrated on the protruding portion 215, it is necessary to design the knife 210 so that the blade life does not become short. Also, in order to maintain the same ultrasonic amplitude transmitted to the knife 210, it is necessary to reduce the mass of other parts of the knife 210 by only the mass increased by the protruding portion 215. For example, it can be realized by reducing the total mass of the knife 210 excluding the protruding portion 215 by the mass of the protruding portion 215, or by configuring and designing a concave portion 216 in the knife 210 together with the protruding portion 215 as shown in FIG. 11 described later. That is, even if the knife 210 is provided with the protruding portion 215, the total mass of the knife 210 must be the same as the total mass of the knife 210 without the protruding portion 215.

[0090] In this figure, the protruding portion 215 is shown as protruding with a triangular sharp shape, but it is not limited to such a shape, and any protruding shape is possible.

[0091] FIG. 9 is a diagram showing a knife according to another modification of the present invention. FIG. 10 is a diagram showing the degree of sticking of the secondary battery material depending on the position where the concave portion of FIG. 9 is provided. FIG. 10(a) is a diagram showing the degree of sticking of the secondary battery material when the first length is shorter than the second length, and FIG. 10(b) is a diagram showing the degree of sticking of the secondary battery material when the first length is longer than the second length.

[0092] The knife described with reference to FIGS. 9 and 10 is a modification of an embodiment of the present invention disclosed in FIGS. 3 and 4, and a detailed description of the same configuration as that described above is omitted.

[0093] Referring to FIGS. 9 and 10, the knife 210 according to another modification of the present invention may include a concave portion 216.

[0094] The recess 216 may be located on the side surface of the knife 210. Specifically, the recess 216 may be located on the first surface 211 and the second surface 212 of the knife 210, respectively. The recess 216 may be an area recessed in the first surface 211 and the second surface 212.

[0095] The recess 216 may be a structure for allowing the secondary battery material to separate from the knife 210 within the shortest time after the knife 210 cuts the sheet 110. That is, when the sheet 110 is cut with the knife 210 including the recess 216, the secondary battery material can hit the recess 216 and separate from the knife 210. Therefore, the contact time between the secondary battery material and the knife 210 can be shortened by the recess 216. Therefore, even if the secondary battery material is stuck to the knife 210 due to the frictional heat generated during cutting, the secondary battery material can ride along the first surface 211 and the second surface 212 of the knife 210 and not be stuck, and can separate from the knife 210 as soon as possible due to the recess 216.

[0096] At this time, the radius of the recess 216 may be 0.01 mm or more. When the radius of the recess 216 is smaller than 0.01 mm, the recess 216 may not be recognized as an unevenness formed on the knife 210, and thus the secondary battery material may also be stuck to the area where the recess 216 is formed. Therefore, the radius of the recess 216 is preferably larger than 0.01 mm. Just because that is the case, it does not mean that the recess 216 can always be formed as long as the radius of the recess 216 is 0.01 mm or more. As an example, the length of the radius of the recess 216 needs to be smaller than the distance from the straight line (shown by the dotted line) extending perpendicular to the third surface 213 with respect to the apex 214 to the first surface 211 or the second surface 212 where the recess 216 is formed.

[0097] The secondary battery material can be separated from the knife 210 with reference to the concave start portion 216a. The concave start portion 216a means the region where the concave portion 216 starts, with reference to the vertex 214 where the first surface 211 and the second surface 212 are in contact. At this time, the length from the vertex 214 to the concave start portion 216a may be such that the first length is d1, and the height of the sheet 110 may be the second length d2.

[0098] More specifically, referring to Fig. 10(a), when the first length d1 is shorter than the second length d2, the concave portion 216 may be located on the first surface 211 and the second surface 212 with a height lower than the second length d2. In this case, when cutting the sheet 110, even if the secondary battery material is burned onto the knife 210 due to frictional heat, the concave portion 216 allows the burned secondary battery material to be separated from the knife 210 without climbing further onto the first surface 211 and the second surface 212.

[0099] In contrast, referring to Fig. 10(b), when the first length d1 is longer than the second length d2, the concave portion 216 may have a height higher than the second length d2 and be located on the first surface 211 and the second surface 212. In this case, when cutting the sheet 110, the secondary battery material may not separate after being burned onto the knife 210 due to frictional heat and may be burned onto the knife 210 to a certain height or more. Therefore, even though the concave portion 216 is provided, there is a high possibility that the cutting quality of the sheet 110 will be defective.

[0100] That is, for the reasons described above, it is preferable that the first length d1 is shorter than the second length d2.

[0101] The knife 210 associated with FIGS. 9 and 10 needs to be designed so that the cutting load is dispersed by the concave portion 216 configuration and the life is not shortened, such as the blade breaking. Also, in order to maintain the same ultrasonic amplitude transmitted to the knife 210, it is necessary to increase the mass of other parts of the knife 210 by only the mass reduced by the concave portion 216. For example, it can be realized by increasing the mass of other regions of the knife 210 without the concave portion 216, or by configuring and designing the protruding portion 215 on the knife 210 together with the concave portion 216 as shown in FIG. 11 described later. That is, even if the knife 210 is provided with the concave portion 216, the total mass of the knife 210 must be the same as the total mass of the knife 210 without the concave portion 216.

[0102] In this figure, the concave portion 216 is shown as being recessed in a circular shape, but it is not limited to such a shape and any recessed shape is possible.

[0103] FIG. 11 is a diagram showing a knife according to another modified example of the present invention.

[0104] The knife described with reference to FIG. 11 is a modified example of an embodiment of the present invention disclosed in FIGS. 7 to 10, and a detailed description of the same configuration as that described above is omitted.

[0105] Referring to FIG. 11, the knife 210 according to another modified example of the present invention may include a protruding portion 215 and a concave portion 216.

[0106] The protruding portion 215 and the concave portion 216 may be respectively located on the side surface of the knife 210. Specifically, the protruding portion 215 and the concave portion 216 may be respectively located on the first surface 211 and the second surface 212. That is, the protruding portion 215 and the concave portion 216 may be both located on each of the first surface 211 and the second surface 212.

[0107] At this time, the mass added from the protruding portion 215 may be the same as the mass decreased from the recessed portion 216. Therefore, even if the protruding portion 215 is added, since the recessed portion 216 is located together with the knife 210, the total mass of the knife 210 including the protruding portion 215 and the recessed portion 216 can be the same as the mass of the knife 210 without the protruding portion 215 and the recessed portion 216.

[0108] As a result, the protruding portion 215 and the recessed portion 216 may be added to the knife 210 and the cutting load may not be dispersed. Instead, by applying the protruding portion 215 and the recessed portion 216 to the knife 210 simultaneously, the overall mass of the knife 210 can be set to be the same as that of the knife 210 without the protruding portion 215 or the recessed portion 216. Therefore, while the cutting load of the knife 210 is not dispersed and the life of the knife 210 is not shortened, it is possible to prevent the secondary battery material from sticking to the knife 210 in the configuration of the protruding portion 215 and the recessed portion 216, and to improve the cutting quality of the sheet 110 and the quality of the electrode.

[0109] In the present invention, although the protruding portion 215 is shown to be formed closer to the apex 214 than the recessed portion 216, and the recessed portion 216 is shown to be formed farther from the apex 214 than the protruding portion 215, the present invention is not limited thereto. As an example, it is also possible that the recessed portion 216 is formed closer to the apex 214 than the protruding portion 215.

[0110] FIG. 12 is a perspective view showing a secondary battery manufacturing apparatus according to another embodiment of the present invention. FIG. 13 is a view showing a modification of the substrate of FIG. 12.

[0111] The secondary battery manufacturing apparatus described with reference to FIGS. 12 and 13 is a modification of an embodiment of the present invention disclosed in FIGS. 3 and 4, and detailed description of the same configuration as that described above is omitted.

[0112] Referring to FIGS. 12 and 13, a secondary battery manufacturing apparatus 100 according to another embodiment of the present invention includes a substrate 130, a cutting member 200, and a vibrator 300.

[0113] The substrate 130 may include an anti-damage layer 131 located on one surface of the substrate 130. In this case, the substrate 130 may have a general plate shape as shown in FIG. 12, or may have a circular roll form as shown in FIG. 13. However, regardless of its shape, the substrate 130 can transfer the sheet 110 while moving in one direction.

[0114] The anti-damage layer 131 may be located on one surface of the substrate 130 where the sheet 110 is located, or may be located facing the cutting member 200. The cutting member 200 can cut the sheet 110 while moving in the first direction D1. In this case, the cutting member 200 can repeatedly contact the anti-damage layer 131.

[0115] The size of the anti-damage layer 131 can correspond to one surface of the substrate 130. Specifically, the size of the anti-damage layer 131 may be the same as or smaller than the size of one surface of the substrate 130. For example, referring to FIG. 12, the anti-damage layer 131 may cover the entire substrate 130. Or, as shown in FIG. 13, the size of the anti-damage layer 131 may cover only a partial area of one surface of the substrate 130. However, even if the anti-damage layer 131 is located only in a partial area of the substrate 130, the anti-damage layer 131 must be located in the area where the cutting member 200 contacts the substrate 130.

[0116] The knife 210 and the substrate 130 may not contact each other. This is because if the knife 210 and the substrate 130 contact each other, the knife 210 may be damaged. Therefore, in order to prevent damage to the knife 210, an anti-damage layer 131 can be provided on the substrate 130 so that the knife 210 can contact the anti-damage layer 131. As a result, the knife 210 does not directly contact the substrate 130 and is not damaged, so the life of the knife 210 is extended and the equipment cost can be saved.

[0117] The damage prevention layer 131 may be coated on one surface of the substrate 130. Alternatively, the damage prevention layer 131 may be separately manufactured in another process and then fixed to one surface of the substrate 130 with an adhesive or the like.

[0118] As an example, the damage prevention layer 131 may be made of a material having a Shore hardness of 5HS to 85HS. Specifically, when the damage prevention layer 131 is made of a substance with a Shore hardness of 5HS or less, the secondary battery material such as the sheet 110 may not be fixed to the damage prevention layer 131. Therefore, it is highly possible that the secondary battery material is not cut by the shearing force of the knife 210 described later, but breaks or detaches. When the damage prevention layer 131 is made of a substance with a Shore hardness of 85HS or more, the knife 210 may be severely worn during friction between the damage prevention layer 131 and the knife 210. In this case, the cutting quality of the sheet 110 and the quality of the electrode may be deteriorated by foreign substances such as iron (Fe) generated from the worn knife 210.

[0119] In this case, the damage prevention layer 131 may be PVC (Polyvinyl Chloride), silicon, MC nylon (Mono Cast Nylon), Teflon (registered trademark), PET (polyethylene terephthalate), or the like. Since the damage prevention layer 131 formed of the above materials is not damaged even when vibration is transmitted from the knife 210 to the damage prevention layer 131, foreign substances such as iron (Fe) do not occur, and the cutting quality of the sheet 110 and the quality of the electrode can be improved.

[0120] In addition, since the material constituting the damage prevention layer 131 has a high heat distortion temperature, its shape is not deformed even when heat is applied by the vibration of the knife 210 during cutting, and the cutting quality of the secondary battery material can be ensured even at high temperatures.

[0121] As another example, the damage prevention layer 131 may be a high-strength and high-performance extreme performance fiber. Specifically, the damage prevention layer 131 may be a material having a tensile strength of 20 g / d or more and an elastic modulus of 500 g / d or more. As an example, the damage prevention layer is a bulletproof and blade-proof material and may be p-aramid or UHMWPE (Ultra High Molecular Weight Polyethylene).

[0122] By configuring the damage prevention layer 131 as described above, even when the damage prevention layer 131 comes into contact with the knife 210 of the cutting member 200, it may not be damaged or cut thereby. That is, when cutting the sheet 110, the cutting member 200 may not come into contact with the substrate 130 even if it comes into contact with the damage prevention layer 131 a plurality of times. Therefore, even if there is such repeated driving of the knife 210, the substrate 130 may not be damaged. Accordingly, the cutting process can be continuously performed, and the process efficiency can be improved.

[0123] In addition, the damage prevention layer 131 can minimize the wear of the blade of the knife 210. Therefore, the sheet 110 can be cut while preventing blade damage of the knife 210, thereby improving the cutting quality of the electrode. And frequent replacement of the knife 210 can be prevented, and the process cost can also be reduced.

[0124] The battery module and the battery pack including the same described above can be applied to various devices. Such devices can be applied to transportation means such as electric bicycles, electric vehicles, and hybrid vehicles. However, the present invention is not limited thereto, and the present invention is applicable to various devices that can use the battery module and the battery pack including the same, and this also belongs to the scope of the rights of the present invention.

[0125] Although the preferred embodiments of the present invention have been described in detail above, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

Explanation of Signs

[0126] 100: Secondary battery manufacturing apparatus 110: Sheet 130: Substrate 200: Cutting member 210: Knife 215: Protrusion 216: Recess 220: Support portion 221: First hole 300: Vibrator 310: Second hole

Claims

1. In a knife including a blade, it includes a first surface and a second surface extending with a predetermined angle toward a first direction which is a cutting direction, and a third surface extending toward a second direction perpendicular to the first direction; one end portion of the first surface and one end portion of the second surface are in contact with each other to form a vertex which is the blade; one end portion and the other end portion of the third surface are in contact with the other end portion of the first surface and the other end portion of the second surface respectively. A knife.

2. The knife according to claim 1, wherein the first surface and the second surface are provided with a protruding portion which is a protruding region.

3. The protruding portion includes a protruding start portion which is a region where the protruding portion starts with reference to the vertex; The knife according to claim 2, wherein the length from the vertex to the protruding start portion is shorter than the height of the sheet.

4. The knife according to claim 1, including a recess which is a region recessed from the first surface and the second surface.

5. The recess includes a recess start portion which is a region where the recess starts with reference to the vertex; The knife according to claim 4, wherein the length from the vertex to the recess start portion is shorter than the height of the sheet.

6. The knife according to claim 4, wherein the radius of the recess is 0.01 mm or more.

7. The knife includes a protruding portion which is a region protruding from the first surface and the second surface, and a recess which is a region recessed from the first surface and the second surface. The knife according to claim 1.

8. The knife according to claim 1, wherein the angle of the vertex is a blade of 120 degrees or less.

9. The knife according to claim 1, wherein the knife is cermet.

10. A secondary battery manufacturing apparatus including the knife according to any one of claims 1 to 9.

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