Cylindrical roll core, through hole method thereof and battery

Abstract

The invention provides a cylindrical roll core, a through hole method thereof and a battery, and the cylindrical roll core through hole method comprises the following steps: pasting an adhesive layer on the periphery of a hollow round needle, and inserting the round needle into the roll core along a hollow cavity of the cylindrical roll core; in the process of inserting the round needle, blowing air into the hollow part of the round needle, so that the collapsed diaphragm in the hollow cavity is arranged to the inner wall of the roll core; after the round needle is completely inserted into the hollow cavity, the round needle is rotated to extrude the diaphragm, and after it is guaranteed that the adhesive layer falls off from the round needle and adheres to the diaphragm, the round needle is pulled out of the hollow cavity. The collapsed diaphragm is arranged on the inner side of the roll core by utilizing gas and then is adhered to the diaphragm through the adhesive layer, so that the diaphragm on the inner side of the roll core is ensured to be uniformly bound and adhered to the inner side of the roll core without collapsing, a welding needle is ensured to penetrate through the roll core without puncturing the diaphragm in the torque welding process, and the welding needle is prevented from puncturing the collapsed diaphragm in the torque welding process of the roll core; and therefore, the yield of the roll core torque welding process is improved, and the production cost of the battery is reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of battery processing, and in particular to a cylindrical winding core, a through-hole method thereof, and a battery. Background Art

[0002] At present, the new energy vehicle industry is developing rapidly, and electric or hybrid vehicles are equipped with batteries. Batteries can generally be divided into cylindrical batteries and square batteries. In the prior art, the cylindrical batteries of vehicles usually use torque welding technology to ensure the welding strength between the positive pole and the collector plate, but the torque welding process is subject to the uniformity of the diaphragm shrinkage during the hot hole process. When the diaphragm shrinks unevenly after the hot hole, the diaphragm is prone to collapse when the hot needle is withdrawn, causing the positive electrode torque welding needle to penetrate the diaphragm from the negative electrode side to the positive electrode side, causing an internal short, thereby affecting the safety of the battery, making the yield of the battery torque welding process low and increasing the production cost of the battery. Summary of the invention

[0003] In order to solve the above technical problems, the present disclosure provides a cylindrical winding core, a through-hole method thereof, and a battery.

[0004] A first aspect of the present disclosure provides a cylindrical core through-hole method, comprising:

[0005] A glue layer is attached to the outer circumference of the hollow round needle, and the round needle is inserted into the cylindrical winding core along the hollow cavity;

[0006] During the process of inserting the round needle, air is blown into the hollow of the round needle, so that the collapsed diaphragm in the hollow cavity is returned to the inner wall of the winding core;

[0007] After the round needle is completely inserted into the hollow cavity, the round needle is rotated to squeeze the diaphragm to ensure that at least part of the adhesive layer falls off the round needle and adheres to the diaphragm, and then the round needle is pulled out of the hollow cavity.

[0008] Optionally, during the process of inserting the round needle, blowing air into the hollow of the round needle so that the collapsed diaphragm in the hollow cavity is returned to the inner wall of the winding core comprises:

[0009] During the process of inserting the round needle into the hollow cavity at a uniform speed, positive pressure gas greater than 20 Pa is continuously blown into the hollow of the round needle, and the gas is continuously blown into the hollow cavity through the hollow of the round needle, so that the collapsed diaphragm in the hollow cavity returns to its original position under the action of air pressure and adheres to the inner wall of the winding core.

[0010] Optionally, rotating the round needle to squeeze the diaphragm to ensure that the adhesive layer falls off the round needle and adheres to the diaphragm includes:

[0011] The adhesive layer includes a first tape and a second tape that are overlapped and attached, the first tape is attached to the outer circumference of the round needle, and the second tape is attached to the outer circumference of the first tape. When the round needle is fully inserted into the hollow cavity, the round needle is rotated in a clockwise direction at an angular speed of 10-20m / min so that the round needle continues to squeeze the diaphragm until the second tape falls off from the first tape and adheres to the diaphragm.

[0012] Optionally, the inner peripheral adhesion of the first tape on the round needle is 100-200g, the outer peripheral adhesion of the first tape and the second tape is less than the inner peripheral adhesion of the first tape, and the outer peripheral adhesion of the second tape and the diaphragm is 800-1100g.

[0013] Optionally, the step of attaching a glue layer to the outer periphery of the hollow round needle comprises:

[0014] The round needle includes a columnar segment and a conical segment connected in sequence along the insertion direction, and a plurality of adhesive layers are pasted at equal intervals on the outer circumference of the columnar segment along the length direction thereof, and a preset gap is formed between the adhesive layer adjacent to the conical segment and the conical segment.

[0015] Optionally, the length of the round needle is 110-130 mm, the diameter of the round needle is 6-8 mm, the diameter of the hollow is 3-5 mm, and three adhesive layers are pasted on the outer circumference of the round needle at equal intervals along the length direction of the round needle, wherein the width of the adhesive layer is 15-20 mm;

[0016] And / or, the diameter of the hollow cavity of the winding core is 6-8 mm, and the outer diameter of the round needle = the diameter of the hollow cavity - 0.5 mm.

[0018] Optionally, inserting the round needle into the cylindrical winding core along the hollow cavity of the cylindrical winding core comprises:

[0019] After aligning the round needle with the center line of the hollow cavity, the round needle is uniformly inserted into the bottom of the hollow cavity along the center line at a speed of 20-30 m / min.

[0020] Optionally, after the round needle is withdrawn from the hollow cavity, the method further comprises:

[0021] After the first adhesive tape is blown off the round needle, a new adhesive layer is pasted on the round needle to start a new cycle.

[0022] A second aspect of the present disclosure provides a cylindrical winding core, which is manufactured by any of the cylindrical winding core through-hole methods described above.

[0023] A third aspect of the present disclosure provides a battery, comprising a shell and a cylindrical winding core as described above, wherein the winding core is accommodated in the shell and is welded and fixed to the bottom of the shell.

[0024] Compared with the prior art, the technical solution provided by the present invention has the following advantages:

[0025] The cylindrical winding core through-hole method provided by the present invention comprises the following steps: sticking an adhesive layer on the outer circumference of a hollow round needle, inserting the round needle into the winding core along the hollow cavity of the cylindrical winding core, and blowing air into the hollow of the round needle when inserting the round needle. The gas is continuously blown into the hollow cavity so that the collapsed diaphragm in the hollow cavity can be reset under the action of air pressure, that is, the collapsed diaphragm is first returned to the inner wall of the winding core by air. After the round needle is completely inserted into the hollow cavity, the round needle is rotated so that the adhesive layer on the round needle and its outer circumference continuously squeezes the diaphragm to ensure that at least part of the adhesive layer falls off the round needle and adheres to the diaphragm, and then the round needle is pulled out of the hollow cavity. Through the above-mentioned arrangement, the collapsed diaphragm is first returned to the inside of the roll core by using gas, and then adhered to the diaphragm by the adhesive layer, so as to ensure that the diaphragm on the inside of the roll core is evenly bound and attached to the inside of the roll core, and the diaphragm will not collapse. It is ensured that the welding needle will not pierce the diaphragm when passing through the roll core during torque welding, thereby avoiding the situation where the welding needle pierces the collapsed diaphragm when the roll core is welded to the battery shell through torque welding, causing a short circuit inside the roll core, affecting the safety of the battery, improving the yield of the roll core torque welding process, and reducing the production cost of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0028] Figure 1 This is a flowchart of the steps of a cylindrical core through-hole method in an embodiment of the present disclosure;

[0029] Figure 2 This is a schematic diagram of the structure of a round needle in an embodiment of the present disclosure;

[0030] Figure 3 It is a schematic diagram of the structure of a round needle and a cylindrical winding core in an embodiment of the present disclosure.

[0031] Reference numerals:

[0032] 1. Round needle; 10. Hollow; 11. Columnar section; 12. Conical section; 2. Glue layer; 3. Winding core. DETAILED DESCRIPTION

[0033] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0035] Reference Figures 1 to 3 As shown, some embodiments of the present disclosure provide a cylindrical core through-hole method, comprising the following steps:

[0036] S101, pasting an adhesive layer 2 on the outer periphery of the hollow round needle 1, and inserting the round needle 1 into the cylindrical winding core 3 along the hollow cavity;

[0037] S102, during the process of inserting the round needle 1, blowing air into the hollow 10 of the round needle 1, so that the collapsed diaphragm in the hollow cavity is returned to the inner wall of the winding core 3;

[0038] S103, after the round needle 1 is completely inserted into the hollow cavity, the round needle 1 is rotated to squeeze the diaphragm, and after ensuring that the adhesive layer 2 falls off the round needle 1 and adheres to the diaphragm, the round needle 1 is pulled out from the hollow cavity.

[0039] Through the above-mentioned cylindrical core through-hole method, the adhesive layer 2 is pasted on the outer periphery of the hollow round needle 1, and the round needle 1 is inserted into the core 3 along the hollow cavity of the cylindrical core 3. When the round needle 1 is inserted, air is blown into the hollow of the round needle 1, and the gas is continuously blown into the hollow cavity, so that the collapsed diaphragm in the hollow cavity can be reset under the action of air pressure, that is, the collapsed diaphragm is first returned to the inner wall of the core 3 by air. After the round needle 1 is completely inserted into the hollow cavity, the round needle 1 is rotated again, so that the round needle 1 and the adhesive layer 2 on its outer periphery continue to squeeze the diaphragm, to ensure that the adhesive layer 2 falls off the round needle 1 and adheres to the diaphragm, and then the round needle 1 is pulled out of the hollow cavity. Through the above-mentioned arrangement, the collapsed diaphragm is first returned to the inner side of the core 3 by using gas, and then at least a portion of the adhesive layer 2 is adhered to the diaphragm to ensure that the diaphragm on the inner side of the core 3 is evenly bound and attached to the inner side of the core 3, and the diaphragm will not collapse. It is ensured that the welding needle will not pierce the diaphragm when passing through the core 3 during torque welding, thereby avoiding the situation where the welding needle pierces the collapsed diaphragm when the core 3 is welded to the battery shell through torque welding, causing a short circuit inside the core 3, affecting the safety of the battery, and improving the yield and stability of the torque welding process of the core 3, reducing the production cost of the battery, and improving the production efficiency of the battery. In the prior art, after the core 3 is manufactured, the positive current collector is welded to the end of the core 3, the core 3 and the positive current collector are placed at the bottom of the battery housing, and the positive current collector is welded to the positive pole. When the diaphragm inside the core 3 collapses, it is easy to cause the welding needle to be misaligned with the positive current collector and the pole during torque welding, causing a cold weld, increasing the DCR, reducing the current capacity, and affecting the electrical performance of the battery. The above-mentioned cylindrical core through-hole method can ensure that the diaphragm inside the core 3 is always attached to the inner wall of the core 3, thereby solving the problem of misalignment between the welding needle and the positive current collector and the pole, and avoiding cold welds.

[0040] The cylindrical core through-hole method disclosed in the present invention can be implemented manually or by automated equipment, for example, by an automated machine or an automated assembly line. Specifically, in step S102, during the process of inserting the round needle 1, air is blown into the hollow of the round needle 1 so that the collapsed diaphragm in the hollow cavity adheres to the inner wall of the hollow cavity, including: the round needle 1 is clamped by the operating end of the automated equipment, and a blowing hole is provided on the automated equipment. During the process of the operating end inserting the round needle 1 into the hollow cavity at a uniform speed, the automated equipment continuously blows a positive pressure gas greater than 20 pa into the hollow 10 through the blowing hole. The gas can be compressed air or nitrogen with a purity greater than 99.99%. The gas is continuously blown into the hollow cavity of the core 3 through the hollow 10, so that the collapsed diaphragm in the hollow cavity returns to its position under the action of the air pressure and adheres to the inner wall of the core 3. The combination of round needle 1 + automation equipment + adhesive layer 2 in the present invention has much lower cost than the metal hot needle + heating mechanism in the prior art, and has no additional power demand, which reduces the manufacturing cost of the battery and poses no safety risk of burns to production personnel, making it more suitable for battery production line operations.

[0041] In step S103, the round needle 1 is rotated to squeeze the diaphragm to ensure that the adhesive layer 2 falls off the round needle 1 and adheres to the diaphragm. Specifically, the adhesive layer 2 is pasted on the outer periphery of the round needle 1 through the adhesive layer structure of the automated equipment, and both sides of the adhesive layer 2 are sticky. For example, adhesive can be used. Two layers of adhesive can be applied on the round needle 1 to achieve stickiness on both sides. The adhesive layer 2 can also be a double-sided tape, and the double-sided tape includes a first tape and a second tape that are overlapped and attached. The inner circumference of the first tape is adhered to the outer circumference of the round needle 1, and the second tape is adhered to the outer circumference of the first tape. After the automated equipment completely inserts the round needle 1 into the hollow cavity of the winding core 3, according to the winding direction between the positive electrode, the diaphragm and the negative electrode during the production process of the winding core 3, when the diaphragm collapses in a clockwise direction, the operating end rotates the round needle 1 at a constant speed at an angular velocity of 10-20m / min in the clockwise direction, so that the round needle 1 continues to squeeze the collapsed diaphragm in the hollow cavity until the second tape falls off smoothly from the outer circumference of the first tape and adheres to the diaphragm, ensuring that the collapsed diaphragm can be attached to the inner wall of the winding core 3, thereby ensuring that the positive electrode torque welding needle passes through the hollow cavity of the winding core 3 and is accurately aligned with the current collecting plate and the pole, avoiding the problem of cold welding caused by inaccurate alignment. In the actual operation process, if the direction of the membrane collapses is counterclockwise, the operating end side rotates the round needle 1 in the counterclockwise direction at an angular velocity of 10-20 m / min until the second side of the tape is successfully adhered to the membrane.

[0042] In some process flows, since the first tape needs to be always adhered to the outer circumference of the circular needle 1 during the rotation of the circular needle 1, and the second tape needs to smoothly fall off from the outer circumference of the first tape as the circular needle 1 rotates to be adhered to the diaphragm, each surface of the first tape and the second tape has a different strength of adhesion, which can be flexibly set according to actual adhesion requirements. For example, the inner circumference adhesion of the first tape on the circular needle is 100-200g, which can be 100g, 150g or 200g, and the outer circumference adhesion of the first tape to the second tape is less than the inner circumference adhesion of the first tape. For example, when the inner circumference adhesion of the first tape is 150g, the outer circumference adhesion of the first tape can be 100g, and the outer circumference adhesion of the second tape to the diaphragm is 800-1100g, which can be 800g, 1000g or 1100g. 00g, the inner periphery of the second tape has no adhesion, thereby ensuring that the first tape will not fall off the round needle 1 when the round needle 1 rotates at a uniform speed, and the inner periphery of the second tape can be easily detached from the outer periphery of the first tape, and the outer periphery of the second tape is quickly adhered to the diaphragm under strong adhesion, and the strong adhesion can ensure that the diaphragm is always attached to the inner wall of the winding core 3 without collapse. Through the above-mentioned setting of the adhesive layer 2, the efficiency of the entire process is improved, and the smooth progress of the diaphragm sticking process is ensured.

[0043] In step S101, the adhesive layer 2 is pasted on the periphery of the hollow round needle 1, which includes: the round needle 1 includes a columnar section 11 and a conical section 12 connected in sequence along the insertion direction. Since the end area of ​​the conical section 12 is smaller, it is better positioned and inserted in the hollow cavity, and the round needle 1 can be better aligned with the hollow cavity, thereby improving the insertion efficiency and speed. Air is blown out from the end of the conical section 12 to return the collapsed diaphragm to the inner wall of the winding core 3. The round needle 1 can be quickly inserted into the winding core 3 along the hollow cavity by taking advantage of the structural advantage of the conical section 12. A plurality of adhesive layers 2 are pasted at equal intervals on the periphery of the columnar section 11 in the length direction, and a preset gap is formed between the adhesive layer 2 adjacent to the conical section 12 and the conical section 12.

[0044] Specifically, in some embodiments, referring to Figure 2 and Figure 3As shown, the round needle 1 has a cylindrical hollow structure. The material of the round needle 1 can be any one of stainless steel, aluminum alloy or other metal materials, and can also be any one or more of polymer composite materials such as high molecular weight PE, CPP, and PET. It is ensured that the hardness of the round needle 1 meets the conditions for extruding the diaphragm, and that the collapsed diaphragm in the core 3 can fit tightly with the inner wall of the core 3 after being pasted with the second side tape, and at the same time, metal chips will not be introduced to cause secondary pollution and trigger the risk of internal short circuit of the core 3. The length H of the round needle 1 can be 110-130mm, the diameter D1 of the round needle 1 can be 6-8mm, the diameter D2 of the hollow of the round needle 1 can be 3-5mm, and three adhesive layers 2 are pasted on the outer circumference of the round needle 1 at equal intervals along the length direction of the round needle 1, wherein the adhesive layer 2 can be flexibly selected according to actual usage requirements, and the material of the adhesive layer 2 itself needs to avoid side reactions with any material in the winding core 3. The width W of the adhesive layer 2 can be 15-20mm, and the distance L between the adhesive layer 2 adjacent to the conical section 12 and the bottom of the conical section 12 can be 20-30mm, so as to prevent the last adhesive layer 2 along the insertion direction from sticking to the collapsed diaphragm too early during the insertion of the round needle 1 into the hollow cavity, thereby affecting the subsequent rotation of the round needle 1 to smoothly fall off the second side tape. The diameter of the hollow cavity of the core 3 is 6-8mm, the outer diameter D1 of the round needle 1 = the diameter of the hollow cavity - 0.5mm, and the length of the round needle 1 is greater than the height of the diaphragm of the core 3, ensuring that the second side tape is evenly and evenly attached to the positive and negative electrode starting ends near the core 3 and the middle area diaphragm of the core 3, ensuring that the collapsed diaphragm in the core 3 is evenly attached, and ensuring that the positive electrode torque welding needle will not pierce the diaphragm when passing through the core 3, thereby avoiding the risk of shorting the battery. And while ensuring that the round needle 1 can be smoothly inserted into the hollow cavity, the gap between the round needle 1 and the diaphragm will not be too large, to prevent the second side tape from being unable to quickly adhere to the diaphragm when the distance between the round needle 1 and the diaphragm is too large, resulting in the diaphragm being unable to be smoothly and quickly placed on the inner wall of the core 3.

[0045] In step S101, the round needle 1 is inserted into the winding core 3 along the hollow cavity of the cylindrical winding core 3, including: after the round needle 1 is aligned with the center line of the hollow cavity by automated equipment, the round needle 1 is uniformly inserted into the bottom of the hollow cavity along the center line at a speed of 20-30m / min. The specific insertion speed of the round needle 1 can be flexibly adjusted according to different battery specifications.

[0046] After the round needle 1 is pulled out from the hollow cavity in step S103, the process further includes: blowing the first adhesive tape off the round needle 1 by automated equipment, and then pasting a new adhesive layer 2 on the round needle 1 to start a new cycle.

[0047] Some other embodiments of the present disclosure also provide a cylindrical winding core 3, which is made by the cylindrical winding core through-hole method as described above, so that the diaphragm on the inner side of the winding core 3 is evenly bound and attached to the inner side of the winding core 3, and the diaphragm will not collapse, ensuring that the welding needle will not pierce the diaphragm when passing through the winding core 3 during torque welding, thereby avoiding the situation where the welding needle pierces the collapsed diaphragm when the winding core 3 is welded to the battery shell by torque welding, causing a short circuit inside the winding core 3, affecting the safety of the battery, improving the yield of the torque welding process of the winding core 3, reducing the production cost of the winding core 3, and improving the production efficiency of the winding core 3. The safety performance of the winding core 3 is further improved, which is conducive to improving the long-term application prospects of the products of battery manufacturers. It can also solve the problem of misalignment between the welding needle and the positive collector and the pole, and avoid the occurrence of cold welding.

[0048] Still other embodiments of the present disclosure provide a battery, comprising a housing and a cylindrical winding core 3 as described above, wherein the winding core 3 is accommodated in the housing and is welded and fixed to the bottom of the housing.

[0049] Specifically, the core 3 can be welded to the bottom of the shell by a torque welding process, wherein the torque welding needle diameter can be 4.5mm, the inner diameter of the core 3 can be 6-8mm, and the welding needle is inserted into the hollow cavity of the core 3. The gap between the welding needle and the inner wall around the core 3 is 0.75-1.75mm, and the torque welding positioning accuracy is ±0.5mm, thereby ensuring that the welding needle does not adhere to the second side tape adhered to the diaphragm, ensuring that the welding needle is accurately aligned with the collector plate and the pole, and ensuring the smooth progress of the torque welding process of the core 3. The battery in the present disclosure is a cylindrical battery, and the cylindrical core through-hole method is specifically applied to the 4680 cylindrical battery. Since the 4680 cylindrical battery has the characteristics of small single cell capacity, full pole ear design and uniform expansion stress distribution, it is the best shell application structure for the high nickel and silicon negative electrode system in terms of high safety, high fast charging and high energy density characteristics. In actual application, the cylindrical core through-hole method provided by the present disclosure can also be applied to 21700 cylindrical batteries or 4695 cylindrical batteries.

[0050] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0051] The above are only specific embodiments of the present disclosure, so that those skilled in the art can understand or implement the present disclosure. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cylindrical core through-hole method, characterized in that: include: A glue layer is attached to the outer circumference of the hollow round needle, and the round needle is inserted into the cylindrical winding core along the hollow cavity; During the process of inserting the round needle, air is blown into the hollow of the round needle, so that the collapsed diaphragm in the hollow cavity is returned to the inner wall of the winding core; After the round needle is completely inserted into the hollow cavity, the round needle is rotated to squeeze the diaphragm to ensure that at least part of the adhesive layer falls off the round needle and adheres to the diaphragm, and then the round needle is pulled out of the hollow cavity.

2. The cylindrical core through-hole method according to claim 1, characterized in that: During the process of inserting the round needle, blowing air into the hollow of the round needle so that the collapsed diaphragm in the hollow cavity is returned to the inner wall of the winding core comprises: During the process of inserting the round needle into the hollow cavity at a uniform speed, positive pressure gas greater than 20 Pa is continuously blown into the hollow of the round needle, and the gas is continuously blown into the hollow cavity through the hollow of the round needle, so that the collapsed diaphragm in the hollow cavity returns to its original position under the action of air pressure and adheres to the inner wall of the winding core.

3. The cylindrical core through-hole method according to claim 1, characterized in that: The rotating of the round needle to squeeze the diaphragm to ensure that the adhesive layer falls off the round needle and adheres to the diaphragm comprises: The adhesive layer includes a first tape and a second tape that are overlapped and attached, the first tape is attached to the outer circumference of the round needle, and the second tape is attached to the outer circumference of the first tape. When the round needle is fully inserted into the hollow cavity, the round needle is rotated in a clockwise direction at an angular speed of 10-20m / min so that the round needle continues to squeeze the diaphragm until the second tape falls off from the first tape and adheres to the diaphragm.

4. The cylindrical core through-hole method according to claim 3, characterized in that: The inner peripheral adhesion of the first tape on the round needle is 100-200g, the outer peripheral adhesion of the first tape and the second tape is smaller than the inner peripheral adhesion of the first tape, and the outer peripheral adhesion of the second tape and the diaphragm is 800-1100g.

5. The cylindrical core through-hole method according to claim 1, characterized in that: The adhesive layer is attached to the outer periphery of the hollow round needle, comprising: The round needle includes a columnar segment and a conical segment connected in sequence along the insertion direction, and a plurality of adhesive layers are pasted at equal intervals on the outer circumference of the columnar segment along the length direction thereof, and a preset gap is formed between the adhesive layer adjacent to the conical segment and the conical segment.

6. The cylindrical core through-hole method according to claim 1, characterized in that: The length of the round needle is 110-130 mm, the diameter of the round needle is 6-8 mm, the diameter of the hollow is 3-5 mm, and three adhesive layers are pasted on the outer circumference of the round needle at equal intervals along the length direction of the round needle, wherein the width of the adhesive layer is 15-20 mm; And / or, the diameter of the hollow cavity of the winding core is 6-8 mm, and the outer diameter of the round needle = the diameter of the hollow cavity - 0.5 mm.

7. The cylindrical core through-hole method according to claim 1, characterized in that: The step of inserting the round needle into the winding core along the hollow cavity of the cylindrical winding core comprises: After aligning the round needle with the center line of the hollow cavity, the round needle is uniformly inserted into the bottom of the hollow cavity along the center line at a speed of 20-30 m / min.

8. The cylindrical core through-hole method according to claim 3, characterized in that: After the round needle is pulled out from the hollow cavity, the method further comprises: After the first adhesive tape is blown off the round needle, a new adhesive layer is pasted on the round needle to start a new cycle.

9. A cylindrical winding core, characterized in that: The cylindrical winding core through-hole is manufactured by the method as claimed in any one of claims 1 to 8.

10. A battery, characterized in that: It comprises a shell and a cylindrical winding core as claimed in claim 9, wherein the winding core is accommodated in the shell and is welded and fixed to the bottom of the shell.

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