Battery pole piece hole pressing device and battery pole piece

Abstract

The utility model relates to a battery pole piece hole pressing device and a battery pole piece. The battery pole piece hole pressing device comprises a roller shaft and roller needles, and the multiple roller needles are arranged on the peripheral side face of the roller shaft and are arranged at intervals; the rigidity of the roller needle is smaller than that of the roller shaft; the roller needle comprises a main body part and a pressure head, one end of the main body part is connected with the roller shaft, and the pressure head is arranged at the other end of the main body part; the surface of the side, opposite to the main body part, of the pressing head is a curved surface, the length of the roller needle is larger than the curvature radius of the curved surface, and the length of the roller needle ranges from 30 micrometers to 40 micrometers. The roller needle presses the surface of the battery pole piece to form a pressing hole; the battery pole piece expands towards the gap in the middle of the pressing hole during expansion, so that the relative expansion of the battery pole piece is prevented from being too large; the plurality of pressing holes arranged at intervals can effectively reduce the actual current density flowing through the battery pole piece, so that the polarization at the interface of the battery pole piece and electrolyte is reduced, the internal resistance is reduced, the formation and growth of dendritic crystals are reduced, the use safety of the battery pole piece is improved, and the service life of the battery pole piece is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of battery production and manufacturing, and in particular to a battery pole piece punching device and a battery pole piece. Background Art

[0002] With the development of battery manufacturing technology, lithium metal is often made into lithium metal foil and used as battery pole pieces at the positive and negative electrodes of batteries due to its high specific capacity and high conductivity.

[0003] In related technologies, electrode sheets are prone to oxidation when powered on, resulting in a large relative volume expansion; and are prone to poor mechanical stability of the SEI film and excessively high local current density, which reduces the overall coulombic efficiency of the battery and shortens the battery's cycle life; in addition, lithium metal battery electrodes are also prone to dendrites during use, posing a risk of short circuit. Utility Model Content

[0004] Based on this, it is necessary to provide a battery electrode pressing device and a battery electrode to address at least one of the problems existing in the above-mentioned battery electrode.

[0005] On the one hand, the present application provides a battery electrode punching device, comprising a roller shaft and a roller needle, wherein a plurality of the roller needles are arranged on the circumferential side surface of the roller shaft and are spaced apart from each other; the stiffness of the roller needle is less than the stiffness of the roller shaft; the roller needle comprises a main body and a pressure head, one end of the main body is connected to the roller shaft, and the pressure head is arranged at the other end of the main body; the surface of the pressure head facing away from the main body is a curved surface, the length of the roller needle is greater than the curvature radius of the curved surface, and the length of the roller needle is 30μm-40μm.

[0006] The above-mentioned battery electrode hole pressing device is configured by arranging a plurality of roller needles spaced from each other on the circumferential side surface of the roller shaft. The rotation of the roller shaft drives the roller needles to rotate, and the pressure head contacts the surface of the battery electrode, and the roller needles press the surface of the battery electrode to form a plurality of spaced pressing holes. The battery electrode produced by using the battery electrode hole pressing device has a plurality of pressing holes on the surface. When the battery electrode expands during use, the lithium metal will expand toward the gap in the middle of the pressing holes, which can effectively avoid the relative excessive expansion of the battery electrode. The plurality of spaced pressing holes can effectively reduce the actual current density flowing through the battery electrode when the battery electrode is working, thereby reducing the polarization at the interface between the battery electrode and the electrolyte, reducing the internal resistance of the battery electrode, reducing the formation and growth of dendrites, and improving the safety and service life of the battery electrode.

[0007] In one embodiment, the plurality of roller needles are arranged in a rectangular array.

[0008] In one embodiment, the straightness tolerance of the circumferential side surface of the roller is less than or equal to 8 μm.

[0009] In one embodiment, the pressure head is a hemispherical structure, and the bottom surface of the pressure head is connected to the main body.

[0010] Furthermore, the straightness tolerance of the spherical side surface of the indenter is less than or equal to 8 μm.

[0011] In one embodiment, the main body is a truncated cone-shaped structure, wherein the end of the main body with a larger cross-sectional area is connected to the roller shaft, and the end of the main body with a smaller cross-sectional area is connected to the pressure head.

[0012] Furthermore, the diameter of the end of the main body with a larger cross-sectional area ranges from 30 μm to 40 μm.

[0013] In one embodiment, the roller includes a central shaft and a sleeve sleeved around the central shaft, the sleeve being connected to one end of the main body. The central shaft is made of stainless steel, and the sleeve is made of EPDM, polylactic acid, or polymethyl methacrylate.

[0014] In one embodiment, the material of the roller needle is EPDM, polylactic acid or polymethyl methacrylate.

[0015] On the other hand, the present application also provides a battery electrode processed and manufactured based on the above-mentioned battery electrode pressing device, the front of which is provided with pressing holes arranged in a rectangular array, the depth of the pressing holes is less than the thickness of the battery electrode, the hole spacing of the pressing holes along the length direction of the battery electrode is 2mm-12mm, and the hole spacing of the pressing holes along the width direction of the battery electrode is 1mm-3mm.

[0016] The above-mentioned battery electrode has pressing holes arranged in a rectangular array on the front side of the battery electrode, and the hole spacing of the pressing holes along the length direction of the battery electrode is 2mm-12mm, and the hole spacing of the pressing holes along the width direction of the battery electrode is 1mm-3mm. This structural setting effectively reduces the actual current density, thereby reducing the polarization at the interface between the battery electrode and the electrolyte, reducing the internal resistance, thereby reducing the formation and growth of dendrites during use, and improving the safety and service life of the battery electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural intuitive diagram of a battery pole piece pressing device and an embodiment of a battery pole piece of the present application.

[0018] Figure 2 This is a top view of a battery electrode sheet pressing device and a battery electrode sheet according to an embodiment of the present application.

[0019] Figure 3 This application is a battery electrode hole pressing device and a battery electrode embodiment of the battery electrode hole pressing device Figure 2 Cross-sectional view at point A.

[0020] Figure 4 This application is a battery electrode hole pressing device and a battery electrode embodiment of the battery electrode hole pressing device Figure 3 A partial enlarged view of point B in the middle.

[0021] Among them, 100, roller shaft; 110, center shaft; 120, sleeve; 200, roller needle; 210, main body; 220, pressure head. DETAILED DESCRIPTION

[0022] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0023] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0024] See Figure 1 , Figure 1 A schematic diagram of the structure of a battery electrode punching device in one embodiment of the present application is shown. The present application provides a battery electrode punching device in one embodiment, comprising a roller shaft 100 and roller needles 200. Multiple roller needles 200 are disposed on the circumferential side of the roller shaft 100 and spaced apart from each other. The roller needles 200 have a lower rigidity than the roller shaft 100. The roller needles 200 include a main body 210 and a pressing head 220. One end of the main body 210 is connected to the roller shaft 100, and the pressing head 220 is disposed at the other end of the main body 210. The surface of the pressing head 220 facing away from the main body 210 is curved. The length of the roller needles 200 is greater than the radius of curvature of the curved surface, and the length of the roller needles is 30 μm to 40 μm.

[0025] It should be noted that the roller needles 200 are arranged perpendicular to the centerline of the roller shaft 100, and are thus radially arranged on the roller shaft 100. The roller shaft 100 has a relatively high rigidity, providing support for the roller needles 200 and ensuring that the overall structure of the battery electrode sheet punching device is not easily deformed. The roller needles 200 are used to contact the battery electrode sheet and press holes on the surface of the battery electrode sheet. During use, the battery electrode sheet is placed on one side of the battery electrode sheet punching device. The roller shaft 100 rotates along its own axis, driving the roller needles 200 to rotate. At the same time, the battery electrode sheet slowly moves along the tangent direction of the roller shaft 100. During this process, the pressing head 220 contacts the surface of the battery electrode sheet and presses holes at intervals on the surface of the battery electrode sheet, thereby obtaining a battery electrode sheet with multiple holes on its surface.

[0026] The part of the roller needle 200 that presses the surface of the battery electrode at one end away from the roller shaft 100 is the pressure head 220. The surface of the pressure head 220 that contacts the battery electrode is a curved surface. When the pressure head 220 contacts the surface of the battery electrode to perform a hole pressing operation, unlike the square and other angular structures that contact the surface of the battery electrode, the pressure applied by the curved surface to the surface of the battery electrode is more uniform, and it is not easy to cause cracking and damage to the surface of the battery electrode.

[0027] Furthermore, the length of the needle roller 200 is greater than the radius of curvature of the curved surface of the indenter 220. Therefore, the needle roller 200 has a slender, needle-like structure, which can press and form a slender pressing hole on the surface of the battery electrode. Furthermore, if the pressing hole formed by the needle roller 200 on the surface of the battery electrode is too shallow, the improvement in the electrical performance of the battery electrode will be insignificant. If the pressing hole is too deep, the mechanical strength of the battery electrode will be weakened, making it susceptible to damage during use. The needle roller 200 has a length of 30μm-40μm, which ensures that the pressing hole formed on the surface of the battery electrode has a depth of 30μm-40μm. This ensures that the electrical properties of the battery electrode obtained by the pressing operation meet the desired effect while not causing damage to the battery electrode.

[0028] The length of the needle roller 200 may be 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm or 40 μm, and is not limited to this length.

[0029] During the punching operation, the battery electrode punching device rotates the roller shaft 100, driving the roller needle 200 to rotate. The roller needle 200 punches holes on the surface of the lithium metal battery electrode, creating multiple pores on the surface of the battery electrode. The resulting expansion of the battery electrode during the punching operation occurs within the pores, preventing the battery electrode from expanding excessively when powered. This effectively reduces the actual current density, thereby lowering polarization at the interface between the battery electrode and the electrolyte, reducing internal resistance, and mitigating the formation and growth of dendrites, thereby improving the safety and service life of the battery electrode.

[0030] Preferably, the plurality of roller needles 200 are arranged in a rectangular array.

[0031] See Figure 2 In one embodiment, roller needles 200 are arranged in a row at equal intervals along the length of the roller shaft 100. Multiple rows of roller needles 200 are spaced apart on the outer circumference of the roller shaft 100. Each row of roller needles 200 has the same number of roller needles 200 and the roller needles 200 are arranged in a corresponding manner, forming a rectangular array. This arrangement ensures that the battery electrode hole pressing device presses evenly distributed pressing holes on the surface of the battery electrode sheet, improving the structural integrity of the battery electrode sheet and ensuring that there are no significant differences in electrical properties at different locations on the battery electrode sheet.

[0032] Preferably, the straightness tolerance of the circumferential side surface of the roller shaft 100 is less than or equal to 8 μm.

[0033] When punching a battery electrode, the side surface of roller 100 abuts against the surface of the electrode, securing the electrode or moving it. The straightness tolerance of roller 100 can be 0μm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, or 8μm. The straightness tolerance of roller 100 is not limited here.

[0034] In one embodiment, the straightness tolerance of the roller shaft 100 is selected to be no more than 8 μm to ensure that the position deviation of the roller needles 200 is within a reasonable range. For example, if the straightness tolerance of the roller shaft 100 is 8 μm, the roller shaft 100 may be slightly bent or tilted around the side surface. This may cause the connection positions of the roller needles 200 in the same row to be non-aligned with the roller shaft 100 or the extension angles of the roller needles 200 in the same row to deviate. This may lead to uneven distribution of the pressing holes formed on the battery electrode, affecting the electrical properties and structural strength of the battery electrode.

[0035] Therefore, by limiting the straightness tolerance of the side surface of the roller 100, it can be ensured that the position deviation of the pressing holes formed on the surface of the battery electrode by the battery electrode pressing device during the pressing operation is within 8μm, so as to ensure that the position and angle offset of the pressing holes on the battery electrode are small, and avoid excessive differences in the electrical properties of various positions of the battery electrode or the structural strength failing to meet the use requirements due to excessive deviation in the distribution of the pressing holes.

[0036] Furthermore, the circumferential runout of the roller 100 does not exceed 8 μm, and can be 0 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, or 8 μm. This ensures that the circumferential surface of the roller 100 is relatively flat, ensuring that when the roller 100 contacts the surface of the battery electrode sheet, the positional deviation between a point on the circumferential surface and a corresponding point on the battery electrode sheet is within 8 μm after one rotation of the roller 100. For example, when the circumferential surface of the roller 100 contacts the surface of the battery electrode sheet, if a point on the circumferential surface of the roller 100 is 8 μm higher than other points on the roller 100 surface, then when the roller 100 contacts the battery electrode sheet, that point contacts the battery electrode sheet surface, while other points do not. The shortest distance from the battery electrode sheet surface is 8 μm, resulting in the depth of the pressure hole formed by the roller needle 200 at other points on the battery electrode sheet surface being 8 μm less than the length of the roller needle 200.

[0037] In this way, the circumferential surface runout of the roller 100 is limited to within 8 μm, so that the depth deviation of the pressing hole formed by the roller needle 200 on the surface of the battery electrode can be within 8 μm, and the roller 100 can be prevented from being bumped when rotating on the surface of the battery electrode during the rotation of the roller 100, causing damage to the battery electrode or the roller 100.

[0038] Preferably, the pressing head 220 is a hemispherical structure, and the bottom surface of the pressing head 220 is connected to the main body 210 .

[0039] See Figure 4 In one embodiment, the curved surface of the pressing head 220 facing away from the main body 210 is a spherical surface, which is used to contact the surface of the battery electrode. When the pressing head 220 contacts the surface of the battery electrode, the pressure applied by the spherical side to the surface of the battery electrode is relatively uniform, and the punching process is less likely to cause cracking and damage on the surface of the battery electrode, thereby improving the consistency of the punching process and the yield rate of the processed battery electrode. In addition, the shape of the spherical structure is relatively uniform, the connection with the main body 210 is relatively smooth, and it is easy to produce. The bottom surface of the pressing head 220 is flat, which facilitates connection with the main body 210 and improves the overall stability of the roller needle 200.

[0040] Furthermore, the straightness tolerance of the spherical side surface of the indenter 220 is less than or equal to 8 μm.

[0041] The straightness tolerance of the spherical side surface of the indenter 220 may be 0 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, or 8 μm. There is no limitation on the straightness tolerance of the spherical side surface of the indenter 220 .

[0042] In one embodiment, the straightness tolerance of the spherical side surface of the pressure head 220 is within 8 μm to ensure that the extension angle of the pressure head 220 relative to the main body 210 does not deviate too much, thereby avoiding uneven pressure applied by the roller needle 200 on the battery electrode due to the large deviation in the extension angle between the pressure head 220 and the main body 210 when the roller needle 200 performs a hole pressing operation on the battery electrode.

[0043] In addition, the circular runout of the spherical side of the press head 220 is less than or equal to 8μm, and the circular runout of the spherical side of the press head 220 can be 0μm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm or 8μm. During the hole pressing operation, the spherical side of the press head 220 contacts and presses the battery electrode to form the bottom of the pressing hole. By limiting the circular runout of the spherical side of the press head 220 to no more than 8μm, it can be ensured that the depth of the pressing hole and the angular deviation of the pressing hole relative to the surface of the battery electrode do not exceed 8μm, thereby avoiding the situation where the shape or angle deviation between multiple pressing holes is too large or the pressing hole does not reach the predetermined depth, resulting in large differences in the electrical properties of the battery electrode at different positions, thereby causing the local current density of the battery electrode to be higher, resulting in the processed battery electrode failing to achieve the predetermined effect.

[0044] Preferably, the main body 210 is a truncated cone structure, and the end of the main body 210 with a larger cross-sectional area is connected to the roller 100 , and the end with a smaller cross-sectional area is connected to the pressure head 220 .

[0045] In one embodiment, the larger bottom surface of the main body 210 is connected to the surface of the roller shaft 100. The main body 210 is arranged along the radial direction of the roller shaft 100, which can improve the connection stability between the roller needle 200 and the roller shaft 100, making the roller needle 200 less likely to break or fall during the punching operation. The smaller bottom diameter of the main body 210 is the same as the diameter of the pressure head 220, which facilitates the connection between the main body 210 and the pressure head 220. The connection transition between the main body 210 and the pressure head 220 is relatively smooth, and there are no sharp corners at the connection, which facilitates the punching operation and avoids uneven force on the battery electrode surface due to contact between sharp corners and the battery electrode during the punching operation, resulting in poor punching quality or even damage to the battery electrode. Similarly, the main body 210 has a truncated cone structure with no sharp corners on the side, which improves the safety of the punching operation.

[0046] Furthermore, the diameter of the end of the main body 210 with a larger cross-sectional area ranges from 30 μm to 40 μm.

[0047] The diameter of the end with the larger cross-sectional area of ​​the main body 210 can be 30μm, 31μm, 32μm, 33μm, 34μm, 35μm, 36μm, 37μm, 38μm, 39μm or 40μm. In one embodiment, the diameter of the end with the larger cross-sectional area of ​​the main body 210 is selected to be 40μm, and the length of the roller needle 200 is 40μm. Since the main body 210 is a truncated cone structure, it can be seen that the diameter of the end with the smaller cross-sectional area of ​​the main body 210 is less than 40μm. At this time, the diameter of the indenter 220 is the same as that of the end with the smaller cross-sectional area of ​​the main body 210, that is, less than 40μm. The length of the indenter 220 is selected to be 15μm, and the length of the main body 210 is 25μm, so as to form the following. Figure 3 The structure of the roller needle 200 is shown. The above arrangement can ensure that the diameter of the pressing hole formed on the battery electrode is 40 μm.

[0048] If the diameter of the pressing hole formed by the roller needle 200 on the surface of the battery electrode is too small, the improvement effect on the electrical performance of the battery electrode will not be obvious. If the diameter of the pressing hole formed is too large, it will cause unexpected damage to the surface structure of the lithium metal during the pressing operation, such as cracks between adjacent pressing holes and cracks around the pressing holes, which will affect the electrical properties of the lithium metal battery electrode and easily cause the battery electrode after the pressing operation to not meet the expected performance. Setting the above parameters can facilitate the pressing operation of the battery electrode, resulting in a battery electrode with good electrical properties and stable structure.

[0049] Preferably, the roller 100 includes a central shaft 110 and a sleeve 120 sleeved around the outer periphery of the central shaft 110, the sleeve 120 being connected to one end of the main body 210. The central shaft 110 is made of stainless steel, and the sleeve 120 is made of EPDM rubber, polylactic acid, or polymethyl methacrylate.

[0050] See Figure 3 In one embodiment, the roller 100 includes a cylindrical central shaft 110 and a sleeve 120 sleeved around the central shaft 110. The roller needles 200 are connected to the sleeve 120. The central shaft 110 provides sufficient support for the sleeve 120 and the roller needles 200, and is made of common materials for easy processing. Because the sleeve 120 is made of a material that does not react with lithium metal, contact between the sleeve 120 and the battery electrode during the punching operation prevents corrosion of the stainless steel central shaft 110 caused by contact with lithium metal, effectively extending the service life of the roller 100.

[0051] Preferably, the material of the needle roller 200 is EPDM, polylactic acid or polymethyl methacrylate.

[0052] In one embodiment, EPDM, polylactic acid, or polymethyl methacrylate materials do not react with lithium metal, effectively extending the service life of the battery electrode hole pressing device. EPDM, polylactic acid, or polymethyl methacrylate materials are harder than lithium metal, ensuring that pressing holes can be formed on the surface of a lithium metal battery electrode.

[0053] In addition, the roller needle 200 and the sleeve 120 are made of the same material, and the roller needle 200 and the sleeve 120 are integrally formed, which is convenient for production and manufacturing, and can improve the stability of the connection between the roller needle 200 and the sleeve 120, so that the connection between the roller needle 200 and the sleeve 120 is not easy to break, ensuring that the battery electrode pressing device can perform the pressing operation stably.

[0054] A battery electrode sheet processed based on the above-mentioned battery electrode sheet pressing device has a front surface provided with pressing holes arranged in a rectangular array, the depth of the pressing holes is less than the thickness of the battery electrode sheet, the hole spacing of the pressing holes along the length direction of the battery electrode sheet is 2mm-12mm, and the hole spacing of the pressing holes along the width direction of the battery electrode sheet is 1mm-3mm.

[0055] The hole spacing of the pressing holes along the length direction of the battery electrode sheet can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm or 12mm. The hole spacing of the pressing holes along the width direction of the battery electrode sheet can be 1mm, 2mm or 3mm.

[0056] In one embodiment, the pressing holes on the battery electrode sheet are all blind holes, ensuring that the pressing holes do not penetrate the battery electrode sheet and affect the structural strength of the battery electrode sheet. The front side of the battery electrode sheet is the side of the battery electrode sheet that contacts the battery electrode sheet pressing device during the pressing operation. Therefore, the pressing holes are located on the front side of the battery electrode sheet. If the hole spacing is too large, the improvement in the electrical performance of the battery electrode sheet will not be significant. If the hole spacing is too small, the pressing holes will be too dense, reducing the mechanical strength of the battery electrode sheet and requiring too high a precision for the pressing operation, making it inconvenient to manufacture.

[0057] The specific implementation process of this application is as follows: A rotating device is connected at both ends of the central shaft 110 of the roller 100, enabling the central shaft 110 to rotate along its own axis, driving the sleeve 120 and the roller needle 200 to rotate. During the punching operation, the battery electrode sheet is placed on one side of the roller 100, and the outer side of the sleeve 120 contacts one side of the battery electrode sheet. The battery electrode sheet is moved along the tangent direction of the roller 100 through friction between the sleeve 120 and the battery electrode sheet, or by a conveyor device provided on the other side of the battery electrode sheet. As the roller 100 rotates, the roller needle 200 presses the surface of the battery electrode sheet to form a rectangular array of punching holes. The formed punching holes are elongated structures. The depth of the formed punching holes is 30μm-40μm, for example, the punching hole depth is 30μm, 31μm, 32μm, 33μm, 34μm, 35μm, 36μm, 37μm, 38μm, 39μm, or 40μm. The aperture of the pressing hole is 30μm, 31μm, 32μm, 33μm, 34μm, 35μm, 36μm, 37μm, 38μm, 39μm or 40μm, and the spacing between adjacent pressing holes in the length direction of the battery electrode is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm or 12mm, and the spacing in the width direction of the battery electrode is 1mm, 2mm or 3mm.

[0058] The beneficial effects achieved by the above embodiment include: by arranging roller needles 200 on the surface of the roller shaft 100, the battery electrode sheet can be processed, so that the surface of the battery electrode sheet is provided with multiple pressing holes arranged in a rectangular array. The pressing holes on the surface of the battery electrode sheet can cause the lithium metal to expand toward the gap in the middle of the pressing holes when the battery electrode sheet expands during use, thereby preventing the battery electrode sheet from expanding too much. The multiple pressing holes can effectively reduce the actual current density flowing through the battery electrode sheet, thereby reducing the polarization at the interface between the battery electrode sheet and the electrolyte, reducing the internal resistance of the battery electrode sheet, and reducing the formation and growth of dendrites, thereby improving the safety and service life of the battery electrode sheet.

[0059] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A battery electrode punching device, characterized in that: It includes a roller shaft and multiple roller needles, and the multiple roller needles are arranged on the circumferential side of the roller shaft and are spaced apart from each other; the stiffness of the roller needles is less than the stiffness of the roller shaft; the roller needle includes a main body and a pressure head, one end of the main body is connected to the roller shaft, and the pressure head is arranged at the other end of the main body; the surface of the pressure head facing away from the main body is a curved surface, the length of the roller needle is greater than the curvature radius of the curved surface, and the length of the roller needle is 30μm-40μm.

2. The battery electrode punching device according to claim 1, characterized in that: The plurality of roller needles are arranged in a rectangular array.

3. The battery electrode punching device according to claim 1, characterized in that: The straightness tolerance of the circumferential side surface of the roller shaft is less than or equal to 8 μm.

4. The battery electrode punching device according to claim 1, characterized in that: The pressure head is a hemispherical structure, and the bottom surface of the pressure head is connected to the main body.

5. The battery electrode punching device according to claim 4, characterized in that: The straightness tolerance of the spherical side surface of the indenter is less than or equal to 8 μm.

6. The battery electrode punching device according to claim 1, characterized in that: The main body is a truncated cone-shaped structure. The end of the main body with a larger cross-sectional area is connected to the roller shaft, and the end of the main body with a smaller cross-sectional area is connected to the pressure head.

7. The battery electrode punching device according to claim 6, characterized in that: The diameter of the end of the main body with a larger cross-sectional area ranges from 30 μm to 40 μm.

8. The battery electrode punching device according to claim 1, characterized in that: The roller shaft includes a central shaft and a sleeve sleeved on the outer periphery of the central shaft, wherein the sleeve is connected to one end of the main body; The material of the central shaft is stainless steel, and the material of the shaft sleeve is EPDM rubber, polylactic acid or polymethyl methacrylate.

9. The battery electrode hole pressing device according to claim 1, characterized in that: The material of the roller needle is EPDM rubber, polylactic acid or polymethyl methacrylate.

10. A battery electrode manufactured based on the battery electrode punching device according to any one of claims 1 to 9, characterized in that: The front of the battery electrode sheet is provided with pressing holes arranged in a rectangular array, the depth of the pressing holes is less than the thickness of the battery electrode sheet, the hole spacing of the pressing holes along the length direction of the battery electrode sheet is 2mm-12mm, and the hole spacing of the pressing holes along the width direction of the battery electrode sheet is 1mm-3mm.

Images