Winding needle and winding equipment

Abstract

The utility model discloses a winding needle and winding equipment. The winding needle comprises an inner needle and an outer needle, the outer needles surround the inner needle in the circumferential direction of the inner needle, and the outer needles are movably arranged on the circumferential side of the inner needle in the radial direction of the inner needle; the first structural part abuts against the outer needle, and the first structural part can move relative to the outer needle in the axial direction of the inner needle so as to push the outer needle to be away from the inner needle in the radial direction of the inner needle; according to the winding needle, the first structural part pushes the outer needle to be away from the inner needle in the radial direction of the inner needle, so that the effect of enlarging the outer diameter of the winding needle is achieved; meanwhile, the first structural part can be separated from the outer needle, and at the moment, the electrode assembly can apply pressure to the winding needle to enable the outer needle to approach the inner needle in the radial direction of the inner needle, so that the effect of reducing the outer diameter of the winding needle is achieved; the outer diameter of the winding needle can be increased or decreased, so that the winding needle can adjust the outer diameter in the winding process of the electrode assembly, and the situation of tab dislocation is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of battery processing, and particularly relates to a winding needle and a winding device. Background Art

[0002] Energy conservation and emission reduction are the keys to the sustainable development of the automotive industry. Electric vehicles have become an important part of the sustainable development of the automotive industry due to their energy-saving and environmental protection advantages. For electric vehicles, battery technology is an important factor related to their development.

[0003] During the process of battery processing, the winding of the electrode assembly is a very important process, and the electrode assembly usually needs to be wound through a winding needle. At present, the winding needle is prone to the misalignment of the tab during the winding process, resulting in a low yield of the electrode assembly. Summary of the Utility Model

[0004] In view of the above problems, the present application provides a winding needle and a winding device, which can alleviate the problem of low yield caused by the misalignment of the tab during the winding process of the electrode assembly.

[0005] In a first aspect, an embodiment of the present application provides a winding needle, including:

[0006] An inner needle;

[0007] At least two outer needles, surrounding the inner needle along the circumferential direction of the inner needle, and the outer needles are movably arranged on the circumferential side of the inner needle along the radial direction of the inner needle;

[0008] A first structural member, abutting against the outer needles, and the first structural member can move relative to the outer needles along the axial direction of the inner needle to push the outer needles away from the inner needle along the radial direction of the inner needle.

[0009] In the technical solution of this embodiment, an outer needle surrounding the inner needle and capable of moving along the radial direction of the inner needle is provided, and a first structural member abutting against the outer needle is provided, so as to push the outer needle away from the inner needle along the radial direction of the inner needle through the first structural member, thereby achieving the effect of expanding the outer diameter of the winding needle; at the same time, the first structural member can also be separated from the outer needle. At this time, under the action of the tension during the winding process of the electrode assembly, the electrode assembly can apply pressure to the winding needle so that the outer needle can move closer to the inner needle along the radial direction of the inner needle, thereby achieving the effect of reducing the outer diameter of the winding needle; enabling the outer diameter of the winding needle to increase or decrease, so that the winding needle can adjust the outer diameter during the winding process of the electrode assembly, thereby reducing the occurrence of tab misalignment.

[0010] In some embodiments, the winding needle further includes an elastic member disposed inside the winding needle. One end of the elastic member is connected to the outer needle, and the other end of the elastic member can be connected to the inner needle or another outer needle. The elastic member is used to apply a force to the outer needle in the direction pointing to the inner needle.

[0011] In the technical solution of this embodiment, a force directed towards the inner needle is applied to the outer needle through an elastic member, so that the elastic member can press the outer needle against the first structural member, and the first structural member can cooperate with the elastic member to drive the outer needle to move closer to or away from the inner needle along the radial direction of the inner needle, so that the coiling needle has the function of expanding and shrinking the outer diameter, and further facilitating better reduction of the situation of ear misalignment during the coiling of the electrode assembly.

[0012] In some embodiments, the first structural member includes a first inclined surface, the first inclined surface is inclined relative to the axis of the inner needle and forms a first included angle with the axis of the inner needle, and the first inclined surface abuts against the outer needle so that the outer needle can move relative to the first structural member along the first inclined surface.

[0013] In the technical solution of this embodiment, the first structural member includes a first inclined surface, and the first inclined surface abuts against the outer needle. At this time, the movement of the first structural member can push the outer needle to move along the first inclined surface in a direction away from the inner needle; at the same time, under the action of the elastic member or the tension of the electrode assembly, the outer needle can also move closer to the inner needle along the first inclined surface when the first structural member moves in the reverse direction, so that the outer diameter of the coiling needle can be expanded or reduced.

[0014] In some embodiments, the angle range of the first included angle is 40° to 50°.

[0015] The technical solution of this embodiment provides a range of included angles for some first inclined surfaces, so as to limit the distance that the outer needle can move along the radial direction of the inner needle through the included angle of the first inclined surface, so that the first structural member can adjust the change of the outer diameter of the coiling needle by moving a short distance, so that the adjustment of the outer diameter of the coiling needle can have a faster response speed; at the same time, it can also reduce the resistance between the first structural member and the outer needle, thereby reducing the frictional loss between the first structural member and the outer needle and improving the service life of the coiling needle.

[0016] In some embodiments, the length range of the first inclined surface is 3 mm to 5 mm.

[0017] The technical solution of this embodiment provides a range of lengths for some first inclined surfaces, so as to limit the distance that the outer needle can move along the radial direction of the inner needle through the length of the first inclined surface, thereby limiting the change range of the outer diameter of the coiling needle to reduce the situation of ear misalignment during the coiling of the electrode assembly.

[0018] In some embodiments, the coiling needle further includes a second structural member. The second structural member and the first structural member are respectively arranged at opposite ends of the inner needle along the axial direction of the inner needle, and the second structural member abuts against the outer needle at least along the axial direction of the inner needle; the first structural member can move relative to the second structural member along the axial direction of the inner needle.

[0019] In the technical solution of this embodiment, the first structural member and the second structural member are arranged at both ends of the inner needle, and the first structural member and the second structural member can respectively abut against both ends of the outer needle; during the movement of the first structural member to push the outer needle to move radially along the inner needle, the outer needle can always abut against the second structural member, so as to jointly support the outer needle through the cooperation of the second structural member and the first structural member, thereby increasing the stability of the outer needle during the movement process and reducing the situation of skew and the like of the outer needle during the movement process.

[0020] In some embodiments, the second structural member includes a second inclined surface, the second inclined surface abuts against the outer needle, and a second included angle is formed between the second inclined surface and the axis of the inner needle;

[0021] The projection of the intersection of the plane where the second inclined surface is located and the plane where the first inclined surface is located along the radial direction of the inner needle is in the middle region of the inner needle.

[0022] In the technical solution of this embodiment, a second inclined surface is provided on the second structural member, and the intersection of the second inclined surface and the first inclined surface is in the middle region of the inner needle, so that the inclination directions of the first inclined surface and the second inclined surface are opposite; during the movement of the first structural member to push the outer needle to move, this setting enables the outer needle to always abut against the second inclined surface and move along the second inclined surface, so as to support the outer needle through the second inclined surface and improve the stability of the outer needle movement.

[0023] In some embodiments, the second included angle is equal to the first included angle.

[0024] In the technical solution of this embodiment, the inclination angles of the second inclined surface and the first inclined surface are the same, so that during the movement of the first structural member to push the outer needle to move, the outer needle can always abut against the second inclined surface and move along the second inclined surface, so as to support the outer needle through the second inclined surface, thereby further improving the stability of the outer needle movement and reducing the situation of skew and the like of the outer needle during the movement process.

[0025] In some embodiments, two third structural members are provided on the outer needle, the two third structural members are arranged at both ends of the outer needle along the axial direction of the inner needle, and the two third structural members respectively abut against the first structural member and the second structural member.

[0026] In the technical solution of this embodiment, two third structural members are provided on the outer needle and respectively abut against the first structural member and the second structural member, so that both the first structural member and the second structural member can support the outer needle through the third structural member, thereby increasing the stability of the outer needle during the movement process and reducing the situation of skew and the like of the outer needle during the movement process.

[0027] In some embodiments, both of the two third structural members include a third inclined surface, one of the two third inclined surfaces is parallel to the adjacent first inclined surface and abuts against the first inclined surface, and the other of the two third inclined surfaces is parallel to the adjacent second inclined surface and abuts against the second inclined surface.

[0028] In the technical solution of this embodiment, a third inclined surface is provided on the third structural member, and the two third inclined surfaces are respectively parallel to the adjacent first inclined surface or the second inclined surface, so that the third structural member is in surface contact with the first structural member and the second structural member, thereby increasing the contact stability between the third structural member and the first structural member and between the third structural member and the second structural member, further increasing the stability during the movement of the outer needle, and reducing the situation of skew and the like of the outer needle during the movement.

[0029] In some embodiments, the first structural member is fixedly connected to the inner needle; the winding needle further includes a driving assembly for driving the inner needle to move along the axial direction of the inner needle, so as to push the outer needle away from the inner needle along the radial direction of the inner needle through the first structural member.

[0030] The technical solution of this embodiment provides some specific structures for driving the movement of the first structural member. The inner needle is driven to move by the driving assembly, and the first structural member is driven to move by the inner needle, so that the first structural member can push the outer needle to move, thereby achieving the effect of adjusting the outer diameter of the winding needle.

[0031] In some embodiments, an air inlet hole is provided on the outer needle; at least two outer needles can enclose an air flow space, the air flow space is communicated with the air inlet hole, and the air flow space is used to be communicated with an air extraction device to form a negative pressure in the air flow space.

[0032] In the technical solution of this embodiment, the air extraction device can extract the air in the air flow space outside the winding needle to form a negative pressure in the air flow space. The negative pressure in the air flow space can adsorb the electrode assembly near the air inlet hole on the outer needle to achieve the effect of fixing the electrode assembly.

[0033] In some embodiments, there are at least two air inlet holes, and the at least two air inlet holes are evenly arranged on the outer needle.

[0034] In the technical solution of this embodiment, there are at least two air inlet holes, so that there can be at least two positions on the outer needle for adsorbing the electrode assembly, thereby improving the fixing stability of the electrode assembly and the fixing effect; the at least two air inlet holes are evenly arranged, so that the adsorption force received by the electrode assembly can be relatively uniform, thereby reducing abnormalities such as deformation caused by uneven force on the electrode assembly.

[0035] In some embodiments, the aperture range of the air inlet hole is 1 mm to 2 mm, and the distance between adjacent two air inlet holes is 2 mm to 4 mm.

[0036] The technical solution of this embodiment provides an aperture range and a spacing range of the air inlet hole, so that the air inlet hole can stably adsorb the electrode assembly and reduce the situation that the electrode assembly or the diaphragm enters the air inlet hole and causes deformation of the electrode assembly.

[0037] In some embodiments, the range of the negative pressure is -50 KPa to -75 KPa.

[0038] The technical solution of this embodiment provides a range of negative pressure in some airflow spaces, so that the coiling needle can adsorb the electrode assembly relatively stably and reduce the situation that the electrode assembly or the diaphragm enters the air inlet hole and causes deformation of the electrode assembly.

[0039] In some embodiments, an air flow channel communicating with the airflow space is opened on the inner needle, and one end of the air flow channel is used to communicate with an air extraction device to extract the gas in the airflow space out of the coiling needle through the air flow channel.

[0040] In the technical solution of this embodiment, an air flow channel is opened in the inner needle, so that the air extraction device can extract the gas in the airflow space through the air flow channel and form a negative pressure, thereby facilitating the air extraction device to extract the gas from the airflow space, and at the same time reducing the arrangement difficulty of each structure inside the coiling needle and saving space.

[0041] In some embodiments, the outer needle includes a middle part, both ends of the middle part along the axial direction of the inner needle are connected with end parts, and the end parts abut against the first structural member; the air inlet holes are at least opened on the middle part, and the airflow space is at least formed between the middle parts of different outer needles.

[0042] In the technical solution of this embodiment, the outer needle is made to include a middle part and end plates, so that the end parts can abut against the first structural member to facilitate the first structural member to push the outer needle to move; the air inlet holes are opened on the middle part to facilitate the coiling needle to fix the electrode assembly near the middle part, so that the coiling needle can fix the electrode assembly more stably.

[0043] In some embodiments, the thickness range of the middle part is 5 mm to 8 mm.

[0044] The technical solution of this embodiment provides a thickness range of some middle parts, so that the middle part can not only have strong strength, but also reduce the occupation of space so that the airflow can be smoothly extracted from the airflow space to the outside of the coiling needle, and at the same time can reduce the weight of the outer needle.

[0045] In some embodiments, the end part is detachably connected to the middle part.

[0046] In the technical solution of this embodiment, the detachable connection of the end part to the middle part can facilitate the installation, replacement and maintenance of the outer needle, and at the same time, it is also convenient for the overall assembly of the coiling needle.

[0047] In some embodiments, a blanking groove is further opened on the circumferential side surface of the outer needle; in the axial direction of the inner needle, at least one end of the blanking groove is communicated with the space outside the coiling needle.

[0048] In the technical solution of this embodiment, a blanking groove is provided on the outer needle, so as to facilitate the blanking device to enter the wound electrode assembly and remove the electrode assembly from the winding needle.

[0049] In a second aspect, some embodiments of the present application further provide a winding device, including the winding needle provided in some embodiments of the first aspect.

[0050] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the following specifically describes the specific embodiments of the present application. Description of the Drawings

[0051] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present application. And in all the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0052] Figure 1 Is a three-dimensional schematic diagram of the winding needle provided in some embodiments of the present application.

[0053] Figure 2 Is a front view schematic diagram of the winding needle provided in some embodiments of the present application.

[0054] Figure 3 Is Figure 2 The cross-sectional schematic diagram at A-A in

[0055] Figure 4 Is Figure 3 The partial enlarged schematic diagram at B in

[0056] Figure 5 Is in another embodiment Figure 3 The partial enlarged schematic diagram at B.

[0057] Figure 6 Is Figure 3 The partial enlarged schematic diagram at C in

[0058] The meanings of the marks in the figure are:

[0059] 100. Winding needle;

[0060] 10. Inner needle; 101. Air flow channel;

[0061] 20. Outer needle; 201. Air flow space; 21. Middle part; 211. Air inlet hole; 22. End part; 221. Third structural member; 2211. Third inclined surface; 222. Protruding part; 23. Blanking groove;

[0062] 30. First structural member; 31. First inclined surface;

[0063] 40. Elastic member;

[0064] 50. Base; 51. Second structural member; 511. Second inclined surface; 52. Cavity; 53. Interface;

[0065] 60. Driving assembly. Detailed implementation manner

[0066] The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solution of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the description of the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0068] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality" is more than two, unless otherwise specifically defined.

[0069] Referring to "embodiment" herein means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0070] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the front and rear associated objects.

[0071] In the description of the embodiments of the present application, the term "plurality" means two or more (including two). Similarly, "multiple groups" means two or more groups (including two groups), and "multiple pieces" means two or more pieces (including two pieces).

[0072] In the description of the embodiments of the present application, for technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the embodiments of the present application.

[0073] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "coupling", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations.

[0074] Currently, from the perspective of the development of the market situation, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power stations, but also widely used in electric transportation such as electric bicycles, electric motorcycles, and electric vehicles, as well as in multiple fields such as military equipment and aerospace. With the continuous expansion of the application fields of power batteries, the market demand is also continuously increasing.

[0075] In the process of battery production, the winding of the electrode assembly is a very important process, and the electrode assembly usually needs to be wound by a winding needle. At present, the winding needle is prone to the situation of tab misalignment during the winding process. Tab misalignment is likely to cause a reduction in the current-carrying area, and even lead to abnormal current flow, thereby reducing the battery capacity; tab misalignment is also likely to cause too high voltage in some areas, affecting the battery life; tab misalignment is also likely to cause welding short circuits, welding detachment, etc.; that is, tab misalignment is likely to have a negative impact on the capacity, life, and safety performance of the electrode assembly.

[0076] The misalignment of the tab may be caused by various reasons, such as insufficient equipment accuracy, deviation of the tab material and size, uneven thickness of the electrode sheet, etc. Among them, the tab has a certain thickness. During the process of winding the electrode assembly around the winding pin, as the number of winding turns of the electrode assembly increases, the circumference of the outermost layer of the electrode assembly gradually increases, while the spacing between the tabs on the electrode assembly is roughly the same, which easily leads to the misalignment between the tabs of each layer.

[0077] Based on the above considerations, in order to alleviate the problem of tab misalignment during the winding of the electrode assembly, an embodiment of the present application provides a winding pin, which includes an inner pin and at least two outer pins arranged around the inner pin. A first structural member is provided, and the first structural member can move along the axial direction of the inner pin and can push the outer pin to move radially away from the inner pin to expand the outer diameter of the winding pin.

[0078] In such a winding pin, when the first structural member moves in one direction along the axial direction of the inner pin, it can abut against the outer pin and push the outer pin to move, so as to expand the outer diameter of the winding pin; and as the electrode assembly is wound, the first structural member can move in the other direction along the axial direction of the inner pin to disengage from the outer pin. At this time, under the tension of the winding of the electrode assembly, the outer pin can move towards the direction close to the inner pin and be pressed against the first structure, so as to reduce the outer diameter of the winding pin and correspondingly reduce the circumference of the outermost circle of the electrode assembly, thereby alleviating the situation of tab misalignment.

[0079] The winding pin and the winding device provided by the embodiment of the present application can wind and form a cylindrical electrode assembly, or can also wind and form a prismatic electrode assembly or an electrode assembly of other shapes. The electrode assembly formed by the winding device can be used as a component for electrochemical reaction in a battery cell, and this battery cell can be used in an electrical device using the battery as a power source or various energy storage systems using the battery as an energy storage element. The electrical device can be, but is not limited to, mobile phones, tablets, laptop computers, electric toys, electric tools, battery cars, electric vehicles, ships, spacecraft, etc. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric aircraft toys, etc., and the spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0080] For the convenience of description in the following embodiments, an example is given in which a winding device of some embodiments of the present application is used to form a square electrode assembly.

[0081] In the first aspect, Figures 1 to 3, some embodiments of the present application provide a coiling needle 100, which includes an inner needle 10, an outer needle 20, and a first structural member 30. Among them, there are at least two outer needles 20, and at least two outer needles 20 surround the inner needle 10 along the circumferential direction of the inner needle 10; the first structural member 30 abuts against the outer needle 20, and the first structural member 30 can move relative to the outer needle 20 along the axial direction of the inner needle 10 to push the outer needle 20 away from the inner needle 10 along the radial direction of the inner needle 10.

[0082] Figures 1 to 3 Among them, the direction where the X-axis is located is the axial direction of the coiling needle 100, which is also the axial direction of the inner needle 10; the radial direction of the coiling needle 100 is the direction perpendicular to the axial direction of the coiling needle 100. For example, the directions where the Y-axis and the Z-axis are located are both the radial direction of the coiling needle 100, which is also the radial direction of the inner needle 10; the circumferential direction of the inner needle 10 is the direction surrounding the X-axis, and the circumferential direction of the inner needle 10 is also parallel to the plane where the Y-axis and the Z-axis are located.

[0083] The inner needle 10 refers to the structure located inside the coiling needle 100. The inner needle 10 is used to drive the coiling needle 100 to rotate. The inner needle 10 can be connected to an external driving structure (such as a motor, etc.) and rotate therewith. That is, the external driving structure can drive the coiling needle 100 to rotate by driving the inner needle 10 to rotate; the shape of the inner needle 10 can be cylindrical, or prismatic or other shapes; the material of the inner needle 10 can include plastic, metal or other materials.

[0084] The outer needle 20 refers to the structure in the coiling needle 100 that contacts the electrode assembly; there are at least two outer needles 20. The number of outer needles 20 can be two, or three or more. At least two outer needles 20 are arranged to surround the inner needle 10 along the circumferential direction of the inner needle 10. That is, at least two outer needles 20 can be combined to form the side wall structure of the coiling needle 100, so that the electrode assembly can be wound on this side wall structure; at least two outer needles 20 cover at least a part of the inner needle 10 along the circumferential direction of the inner needle 10, so as to facilitate the electrode assembly to be wound on the side wall structure formed by the outer needles 20.

[0085] Since at least two outer needles 20 surround the inner needle 10 and are combined to form the side wall structure of the coiling needle 100, the shape of the outer needle 20 can affect the shape of the coiling needle 100; accordingly, the outer needle 20 can be an arc-shaped sheet structure, and at this time the coiling needle 100 can be a cylindrical structure; the outer needle 20 can also be a flat plate structure, and at this time the coiling needle 100 can be a prismatic structure. The outer needle 20 can also be a structure of other shapes.

[0086] The material of the outer needle 20 can include plastic, metal or other materials; the material of the outer needle 20 and the inner needle 10 can be the same or different.

[0087] The outer needle 20 is disposed on the circumferential side of the inner needle 10 so as to be radially movable relative to the inner needle 10, that is, the outer needle 20 can move relative to the inner needle 10 to approach or move away from the inner needle 10 along the radial direction of the inner needle 10; the outer needle 20 can be directly slidably connected to the inner needle 10, or can move along the radial direction of the inner needle 10 under the restriction of a guiding structure. By way of example, it can be through a guide rail, a guide shaft or other structures with guiding capabilities, and the outer needle 20 can move along other guiding structures such as the guide rail and the guide shaft, so that the outer needle 20 moves along the radial direction of the inner needle 10.

[0088] The first structural member 30 refers to a member that can move relative to the inner needle 10 in the coiling needle 100; the first structural member 30 can be disposed on the inner needle 10 and move relative to the inner needle 10, or can be disposed on other structures of the coiling needle 100 and move relative to the inner needle 10. By way of example, the first structural member 30 can be a rod-shaped structure, a sheet-shaped structure or a structure of other shapes disposed on one side of the inner needle 10, and the first structural member 30 can also be an annular structure, a cylindrical structure or a structure of other shapes sleeved on the inner needle 10; the material of the first structural member 30 can include plastics, metals or other materials.

[0089] The first structural member 30 can move relative to the outer needle 20 along the axial direction X of the inner needle 10, and the first structural member 30 abuts against the outer needle 20, so that the movement of the first structural member 30 can push the outer needle 20 to move away from the inner needle 10 along the radial direction Y of the inner needle 10. In some embodiments, the first structural member 30 can be a wedge block, and the outer needle 20 abuts against the inclined surface of the wedge block. At this time, the movement of the wedge block along the axial direction of the inner needle 10 can push the outer needle 20 to move along the inclined surface of the wedge block to move away from the inner needle 10; in other embodiments, the first structural member 30 can be a connecting rod, one end of the connecting rod can move along the axial direction of the inner needle 10, and the other end of the connecting rod abuts against the outer needle 20. At this time, the movement of one end of the connecting rod along the axial direction of the inner needle 10 can push the other end to move away from the inner needle 10; it can be understood that the first structural member 30 can also include other structures, not limited to the above two.

[0090] The first structural member 30 can abut against the edge of the outer needle 20 along the axial direction X of the inner needle 10, or a structural member can be provided on the side of the outer needle 20 facing the inner needle 10, and the first structural member 30 can be made to abut against this structural member.

[0091] Since there are at least two outer needles 20, the first structural member 30 can have only one and abut against each outer needle 20; the first structural member 30 can also have two or more, so that each outer needle 20 can correspond to at least one first structural member 30; it can be understood that in the case where there are multiple first structural members 30, the multiple first structural members 30 should be able to move synchronously to drive the outer needles 20 to move synchronously.

[0092] The movement of the first structural member 30 along the axial direction X of the inner needle 10 can be achieved through various structures. In some embodiments, a sliding groove extending along the axial direction X of the inner needle 10 is provided on the inner needle 10, and at least a part of the first structural member 30 can be received in the sliding groove and slide along the sliding groove; in other embodiments, a guiding shaft extending along the axial direction X of the inner diameter can be provided on the inner needle 10, the guiding shaft passes through the first structural member 30, and the first structural member 30 can slide along the guiding shaft; in still other embodiments, the inner needle 10 can directly pass through the first structural member 30, that is, the first structural member 30 is sleeved on the inner needle 10, so that the first structural member 30 can slide along the axial direction X of the inner needle 10.

[0093] It can be understood that the movement of the first structural member 30 in one direction (for example Figure 3 moving right along the X-axis in the figure) can push the outer needle 20 away from the inner needle 10 to increase the outer diameter of the coiling needle 100, but the movement of the first structural member 30 in the other direction (for example Figure 3 moving left along the X-axis in the figure) may cause the outer needle 20 to disengage from the first structural member 30. At this time, it is not easy for the first structural member 30 to drive the outer needle 20 to move; during the process of winding the electrode assembly around the coiling needle 100, this situation can utilize the pressure exerted by the electrode assembly wound around the coiling needle 100 on the coiling needle 100 to reduce the outer diameter of the coiling needle 100. For example, the tension on the electrode assembly can exert a pressure on the coiling needle 100 in the direction pointing to the inner needle 10. In the case where the first structural member 30 moves in the other direction (for example Figure 3 moving left along the X-axis in the figure), the outer needle 20 disengages from the first structural member 30, and the first structural member 30 cannot provide support for the outer needle 20. At this time, the pressure generated by the electrode assembly can cause the outer needle 20 to move in the direction close to the inner needle 10 and re-engage with the first structural member 30, so as to achieve the effect of reducing the outer diameter of the coiling needle 100.

[0094] During the process of winding the electrode assembly around the coiling needle 100, as the number of winding turns of the electrode assembly increases, the outer diameter of the coiling needle 100 can be gradually reduced to reduce the situation of the ear misalignment on the outermost layer of the electrode assembly; in the case where the ear misalignment is caused by other reasons during the winding process of the electrode assembly, the outer diameter of the coiling needle 100 can also be increased or reduced according to the situation to relieve the situation of ear misalignment.

[0095] In this embodiment, the outer needle 20 is pushed by the first structural member 30 to move radially away from the inner needle 10 along the radial direction of the inner needle 10, so as to achieve the effect of expanding the outer diameter of the coiling needle 100; at the same time, the first structural member 30 can also be separated from the outer needle 20. At this time, under the action of the tension during the coiling process of the electrode assembly, the electrode assembly can apply a pressure to the coiling needle 100 so that the outer needle 20 can move radially close to the inner needle 10 along the radial direction of the inner needle 10, thereby achieving the effect of reducing the outer diameter of the coiling needle 100; the outer diameter of the coiling needle 100 can be increased or decreased, so that the coiling needle 100 can adjust the outer diameter during the coiling process of the electrode assembly to adapt to different situations and alleviate the situation of tab misalignment.

[0096] Reference Figure 2 、 Figure 3 , in some embodiments, the coiling needle 100 further includes an elastic member 40 disposed inside the coiling needle 100. One end of the elastic member 40 is connected to the outer needle 20, and the other end of the elastic member 40 can be connected to the inner needle 10 or another outer needle 20. The elastic member 40 is used to apply a force to the outer needle 20 in the direction pointing to the inner needle 10.

[0097] The elastic member 40 refers to a structure with elasticity in the coiling needle 100; the elastic member 40 can include a spring, a rubber strip or other elastic structures; the material of the elastic member 40 can include metal, rubber or other materials with elasticity.

[0098] The elastic member 40 is disposed inside the coiling needle 100, that is, the elastic member 40 is located between at least two outer needles 20; the elastic member 40 is used to apply a force to the outer needle 20 in the direction pointing to the inner needle 10. When the first structural member 30 moves and has a tendency to separate from the outer needle 20, the elastic member 40 can drive the outer needle 20 to move in the direction of the inner needle 10 to approach the inner needle 10 and abut against the first structural member 30; for example, Figure 3 for example, when the first structural member 30 moves to the left, the first structural member 30 has a tendency to separate from the outer needle 20. At this time, the elastic member 40 can drive the outer needle 20 to move in the direction of approaching the inner needle 10 and can make the outer needle 20 press against the first structural member 30.

[0099] When the outer needle 20 moves in the direction away from the inner needle 10, the elastic member 40 is in a stretched state and applies a force to the outer needle 20 to approach the inner needle 10; when the outer needle 20 is at the position closest to the inner needle 10, the elastic member 40 can be in a stretched state or in an unloaded natural state.

[0100] One end of the elastic member 40 is connected to the outer needle 20, and the other end of the elastic member 40 can be connected to the inner needle 10; one end of the elastic member 40 is connected to the outer needle 20, and the other end of the elastic member 40 can also be connected to another outer needle 20. When there are three or more outer needles 20, the outer needle 20 can be connected to each outer needle 20. Since multiple outer needles 20 are arranged circumferentially around the inner needle 10, when the elastic member 40 is connected to each outer needle 20, the forces exerted by the elastic member 40 on each outer needle 20 can intersect on the axis of the inner needle 10; the elastic member 40 can also be connected to both the inner needle 10 and each outer needle 20. For example, the middle part of the elastic member 40 is sleeved on the inner needle 10 and is respectively connected to each outer needle 20 at the edge.

[0101] According to the material of the elastic member 40, the elastic member 40 can be connected to the corresponding outer needle 20 and inner needle 10 by means of welding, gluing, etc., or can also be connected to the corresponding outer needle 20 and inner needle 10 by means of screwing, hanging, etc.

[0102] Exemplarily, the elastic member 40 is a rubber ring, and a hanging portion is provided on one side of each outer needle 20 facing the inner needle 10. The hanging portions of each outer needle 20 are distributed along the circumferential side of the inner needle 10. At this time, the rubber ring surrounds outside all the hanging portions, and each hanging portion can extend into the rubber ring and abut against the inner wall of the rubber ring; when the outer needle 20 moves in a direction away from the inner needle 10, the rubber ring deforms. When the first structural member 30 has a tendency to disengage from the outer needle 20, the rubber ring has a tendency to return to its original shape and causes each outer needle 20 to move in a direction close to the inner needle 10, so as to press the outer needle 20 against the first structural member 30, thereby achieving the effect of reducing the outer diameter of the coiled needle 100.

[0103] In this embodiment, a force is applied to the outer needle 20 by the elastic member 40 in a direction pointing towards the inner needle 10, so that the elastic member 40 can press the outer needle 20 against the first structural member 30, and the first structural member 30 can cooperate with the elastic member 40 to drive the outer needle 20 to move closer to or away from the inner needle 10 along the radial direction of the inner needle 10, so that the coiled needle 100 has the functions of expanding and reducing the outer diameter, and the coiled needle 100 does not need to rely on the winding pressure of the electrode assembly to reduce the outer diameter, thereby facilitating better reduction of the situation of ear misalignment during the winding of the electrode assembly.

[0104] Reference Figures 2 to 5 In some embodiments, the first structural member 30 includes a first inclined surface 31. The first inclined surface 31 is inclined relative to the axis of the inner needle 10 and forms a first included angle with the axis of the inner needle 10. The first inclined surface 31 abuts against the outer needle 20, so that the outer needle 20 can move relative to the first structural member 30 along the first inclined surface 31.

[0105] The first inclined surface 31 refers to the inclined surface provided on the first structural member 30, and the first inclined surface 31 is inclined relative to the axis of the inner needle 10; the first inclined surface 31 and the axis of the inner needle 10 can form a first included angle, and the first included angle is the Figure 4 , Figure 5 included angle shown as angle a in

[0106] ; there can be various inclination directions of the first inclined surface 31. Different inclination directions of the first inclined surface 31 result in different movement directions required for the first structural member 30 to push the outer needle 20 away from the inner needle 10. Figure 4 For example, one end of the first inclined surface 31 faces the inside of the coiling needle 100, and the other end of the first inclined surface 31 can be inclined in the direction towards the outside of the coiling needle 100 and away from the axis of the inner needle 10. At this time, the movement of the first structural member 30 towards the inside of the coiling needle 100 can push the outer needle 20 to move away from the inner needle 10; referring to

[0107] ; the right end of the first inclined surface 31 faces the inside of the coiling needle 100, and the left end of the first inclined surface 31 is inclined upwards to the left. At this time, the rightward movement of the first structural member 30 can push the outer needle 20 to move upwards along the first inclined surface 31 to be away from the inner needle 10. Figure 5 For example, one end of the first inclined surface 31 faces the inside of the coiling needle 100, and the other end of the first inclined surface 31 can also be inclined in the direction towards the outside of the coiling needle 100 and close to the axis of the inner needle 10. At this time, the movement of the first structural member 30 towards the outside of the coiling needle 100 can push the outer needle 20 to move away from the inner needle 10; referring to Figure 5 ; the right end of the first inclined surface 31 faces the inside of the coiling needle 100, and the left end of the first inclined surface 31 is inclined downwards to the left. At this time, the leftward movement of the first structural member 30 can push the outer needle 20 to move upwards along the first inclined surface 31 to be away from the inner needle 10.

[0108] In this embodiment, the first structural member 30 includes the first inclined surface 31, and the first inclined surface 31 abuts against the outer needle 20. At this time, the movement of the first structural member 30 can push the outer needle 20 to move away from the inner needle 10 along the first inclined surface 31; meanwhile, under the action of the elastic member 40 or the tension of the electrode assembly, the outer needle 20 can also approach the inner needle 10 along the first inclined surface 31 when the first structural member 30 moves in the reverse direction, so that the outer diameter of the coiling needle 100 can be enlarged or reduced.

[0109] Referring to Figures 2 to 5 , in some embodiments, the angle range of the first included angle is 40° - 50°; for example, the angle of the first included angle can be 40°, 42°, 44°, 45°, 46°, 48°, 50° or other values.

[0110] The first included angle is the included angle formed by the intersection of the first inclined surface 31 and the axis of the inner diameter, that is, the Figure 4 , Figure 5 included angle shown as angle a in

[0111] The angle of the first included angle of the first inclined surface 31 can affect the relationship between the moving distance of the first structural member 30 and the moving distance of the outer needle 20, that is, the larger the angle of the first included angle, the larger the distance that the outer needle 20 is pushed to move when the first structural member 30 moves a unit distance.

[0112] The angle range of the first included angle is 40° to 50°, so that the movement of the first structural member 30 can drive the outer needle 20 to move on the radial direction Y of the inner needle 10 relatively quickly, so that the adjustment of the outer diameter of the coiling needle 100 can have a relatively fast response speed. At the same time, the frictional resistance between the first inclined surface 31 and the outer needle 20 can be made smaller, reducing frictional loss and extending the service life.

[0113] Exemplarily, the angle of the first included angle can be 50°. At this time, the first structural member 30 can push the outer needle 20 to move a relatively large distance by moving a relatively small distance, so that the movement of the first structural member 30 can drive the outer needle 20 to move on the radial direction Y of the inner needle 10 relatively quickly, so that the adjustment of the outer diameter of the coiling needle 100 can have a relatively fast response speed.

[0114] Exemplarily, the angle of the first included angle can be 45°. This setting can not only make the adjustment of the outer diameter of the coiling needle 100 have a relatively fast response speed, but also reduce the frictional force between the outer needle 20 and the first inclined surface 31, thereby reducing frictional loss.

[0115] Exemplarily, the angle of the first included angle can be 40°. At this time, the frictional resistance between the first inclined surface 31 and the outer needle 20 is smaller and the frictional loss is lower.

[0116] In this embodiment, the distance that the outer needle 20 can move along the radial direction of the inner needle 10 is limited by the included angle of the first inclined surface 31, so that the movement of the first structural member 30 can adjust the change of the outer diameter of the coiling needle 100 by moving a relatively short distance, and the adjustment of the outer diameter of the coiling needle 100 can have a relatively fast response speed. At the same time, the resistance between the first structural member 30 and the outer needle 20 can be reduced, thereby reducing the frictional loss between the first structural member 30 and the outer needle 20 and improving the service life of the coiling needle 100.

[0117] Reference Figures 2 to 5 In some embodiments, the length range of the first inclined surface 31 is 3 mm to 5 mm; Exemplarily, the length of the first inclined surface 31 can be 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm or other values.

[0118] The length of the first inclined surface 31 is the dimension of the first inclined surface 31 in the direction of its inclination angle, that is, the dimension shown as L1 in Figure 4 、 Figure 5 .

[0119] The length of the first inclined surface 31 can affect the relationship between the moving distance of the first structural member 30 and the moving distance of the outer needle 20, that is, the greater the length of the first inclined surface 31, the greater the maximum distance that the outer needle 20 can move.

[0120] The length range of the first inclined surface 31 is set to 3 mm to 5 mm, so that the first inclined surface 31 can not only meet the requirements of outer diameter size adjustment, but also reduce the size of the first structural member 30, thereby reducing the space requirement of the first structural member 30.

[0121] Exemplarily, the length of the first inclined surface 31 can be 3 mm, and the angle of the first included angle can be 50°. At this time, the first structural member 30 can move a small distance to push the outer needle 20 to move a large distance, so that the movement of the first structural member 30 can drive the outer needle 20 to move on the radial direction Y of the inner needle 10 faster, thereby enabling the outer diameter adjustment of the coiling needle 100 to have a faster response speed.

[0122] Exemplarily, the length of the first inclined surface 31 can be 4 mm, and the angle of the first included angle can be 45°. This setting can not only enable the outer diameter adjustment of the coiling needle 100 to have a faster response speed, but also reduce the friction force between the outer needle 20 and the first inclined surface 31, thereby reducing the frictional loss.

[0123] Exemplarily, the length of the first inclined surface 31 can be 5 mm, and the angle of the first included angle can be 40°. At this time, the frictional resistance between the first inclined surface 31 and the outer needle 20 is smaller, and the frictional loss is lower.

[0124] The technical solution of this embodiment provides some length ranges of the first inclined surface 31 to limit the distance that the outer needle 20 can move along the radial direction of the inner needle 10 through the length of the first inclined surface 31, thereby limiting the change range of the outer diameter of the coiling needle 100 to reduce the occurrence of ear misalignment during the winding process of the electrode assembly.

[0125] Reference Figures 2 to 6 , in some embodiments, the coiling needle 100 further includes a second structural member 51. The second structural member 51 and the first structural member 30 are respectively arranged at opposite ends of the inner needle 10 along the axial direction of the inner needle 10, and the second structural member 51 abuts against the outer needle 20 at least along the axial direction of the inner needle 10; the first structural member 30 can move axially relative to the second structural member 51 along the inner needle 10.

[0126] The second structural member 51 refers to the structure in the coiling needle 100 that is used to cooperate with the first structural member 30 to support the outer needle 20; the second structural member 51 can be connected to the inner needle 10, or can be connected to other structures of the coiling needle 100. The second structural member 51 can also be an independent component; the second structural member 51 can be a rod-shaped structure, or can be a block-shaped structure or a structure of other shapes; the material of the second structural member 51 can include plastics, metals or other materials.

[0127] The second structural member 51 abuts against the outer needle 20. Since there are at least two outer needles 20, the second structural member 51 can be only one and abut against each outer needle 20; the second structural member 51 can also have two or more, so that each outer needle 20 can correspond to at least one second structural member 51; when the second structural member 51 cooperates with the first structural member 30, each outer needle 20 has at least two supported parts, so that the outer needle 20 can move more stably along the radial direction of the inner needle 10.

[0128] The second structural member 51 abuts against the outer needle 20 at least along the axial direction X of the inner needle 10, that is, the second structural member 51 can at least apply a force to the outer needle 20 along the axial direction X of the inner needle 10 and pointing to the outer needle 20; when the first structural member 30 moves along the axial direction X of the inner needle 10 and pushes the outer needle 20 to move through the first inclined surface 31, this force can balance the force applied by the first inclined surface 31 to the outer needle 20 parallel to the axial direction X of the inner needle 10, and can limit the movement of the second structural member 51 in the axial direction X of the inner needle 10, so that the outer needle 20 can move better along the radial direction Y of the inner needle 10.

[0129] The first structural member 30 and the second structural member 51 are respectively located at both ends of the inner needle 10 along the axial direction X of the inner needle 10, so that the first structural member 30 and the second structural member 51 respectively support the opposite sides of the outer needle 20, thereby being able to better improve the stability of the outer needle 20 during movement and reduce the occurrence of skew and other situations.

[0130] The first structural member 30 can move relative to the second structural member 51 along the axial direction X of the inner needle 10. On the basis that the first structural member 30 can move, the second structural member 51 can be fixed relative to the coiling needle 100 or can be movable relative to the coiling needle 100.

[0131] In this embodiment, the first structural member 30 and the second structural member 51 are arranged at both ends of the inner needle 10, and the first structural member 30 and the second structural member 51 can respectively abut against both ends of the outer needle 20; during the process that the first structural member 30 moves and pushes the outer needle 20 to move along the radial direction of the inner needle 10, the outer needle 20 can always abut against the second structural member 51, so as to jointly support the outer needle 20 through the cooperation of the second structural member 51 and the first structural member 30, thereby being able to increase the stability of the outer needle 20 during movement and reduce the occurrence of skew and other situations of the outer needle 20 during movement.

[0132] Reference Figures 2 to 6 , in some embodiments, the second structural member 51 includes a second inclined surface 511. The second inclined surface 511 abuts against the outer needle 20, and a second included angle is formed between the second inclined surface 511 and the axis of the inner needle 10; the projection of the intersection of the plane where the second inclined surface 511 is located and the plane where the first inclined surface 31 is located along the radial direction Y of the inner needle 10 is in the middle region of the inner needle 10.

[0133] The second inclined surface 511 refers to the inclined surface provided on the second structural member 51. The second inclined surface 511 and the axis of the inner needle 10 can form a second included angle, that is, the second inclined surface 511 is inclined relative to the axis of the inner needle 10, and the second included angle is Figure 4 、 Figure 5 the included angle shown as the middle angle a.

[0134] The intersection of the plane where the second inclined surface 511 is located and the plane where the first inclined surface 31 is located means that the second inclined surface 511 and the first inclined surface 31 are not parallel; the projection of the intersection along the radial direction Y of the inner needle 10 is in the middle region of the inner needle 10, that is, the inclination directions of the first inclined surface 31 and the second inclined surface 511 are opposite, and the middle region of the inner needle 10 is the region where the inner needle 10 is located between the first structural member 30 and the second structural member 51 along its axial direction X. For example, when the first included angle is greater than 90°, the second included angle is less than 90°; this setting enables the end of the outer needle 20 abutting against the first inclined surface 31 to move along the first inclined surface 31, and the end of the outer needle 20 abutting against the second inclined surface 511 can move synchronously along the second inclined surface 511, and can make the outer needle 20 move more smoothly and not easily skew during the movement, so as to provide support for the electrode assembly and reduce abnormalities such as deformation of the electrode assembly during winding.

[0135] In this embodiment, the second inclined surface 511 is provided on the second structural member 51, and the intersection of the second inclined surface 511 and the first inclined surface 31 is in the middle region of the inner needle 10, so that the inclination directions of the first inclined surface 31 and the second inclined surface 511 are opposite; during the movement of the first structural member 30 and the pushing of the outer needle 20 to move, this setting enables the outer needle 20 to always abut against the second inclined surface 511 and move along the second inclined surface 511, so as to support the outer needle 20 through the second inclined surface 511 and improve the stability of the movement of the outer needle 20.

[0136] Refer to Figures 2 to 6 , in some embodiments, the second included angle is equal to the first included angle.

[0137] The second included angle being equal to the first included angle means that the inclination angles of the second inclined surface 511 and the first inclined surface 31 are the same; since both the first structural member 30 and the second structural member 51 abut against the outer needle 20, the same inclination angles of the first inclined surface 31 and the second inclined surface 511 enable the end of the outer needle 20 abutting against the first inclined surface 31 to move along the first inclined surface 31, and the end of the outer needle 20 abutting against the second inclined surface 511 can move synchronously along the second inclined surface 511, and can make the outer needle 20 move more smoothly and not easily skew during the movement, so as to provide support for the electrode assembly and reduce abnormalities such as deformation of the electrode assembly during winding.

[0138] The second inclined surface 511 can provide an outer needle 20 with a force parallel to the axial direction X of the inner needle 10, which can limit the movement of the outer needle 20 in the axial direction X of the inner needle 10. At the same time, the second inclined surface 511 can also provide an outer needle 20 with a force parallel to the radial direction Y of the inner needle 10, which can support and hold the outer needle 20, thereby further reducing the skew of the outer needle 20 during movement and improving the movement stability of the outer needle 20.

[0139] Exemplarily, one end of the first inclined surface 31 faces the inside of the coiling needle 100, and the other end of the first inclined surface 31 can be inclined in a direction facing the outside of the coiling needle 100 and away from the axis of the inner needle 10. At this time, one end of the second inclined surface 511 faces the inside of the coiling needle 100, and the other end of the second inclined surface 511 can be inclined in a direction facing the outside of the coiling needle 100 and away from the axis of the inner needle 10. At this time, when the first structural member 30 moves closer to the second structural member 51, it can push the outer needle 20 to move smoothly away from the inner needle 10; refer to Figure 4 , Figure 6 , the right end of the first inclined surface 31 faces the inside of the coiling needle 100, the left end of the first inclined surface 31 is inclined upward to the left, the left end of the second inclined surface 511 faces the inside of the coiling needle 100, and the right end of the second inclined surface 511 is inclined upward to the right. At this time, when the first structural member 30 moves to the right, it can push the outer needle 20 to move upward more stably along the first inclined surface 31 and the second inclined surface 511 to move away from the inner needle 10.

[0140] In this embodiment, the inclination angles of the second inclined surface 511 and the first inclined surface 31 are made the same, so that during the movement of the first structural member 30 to push the outer needle 20 to move, the outer needle 20 can always abut against the second inclined surface 511 and move along the second inclined surface 511, so as to support the outer needle 20 through the second inclined surface 511, thereby further improving the movement stability of the outer needle 20 and reducing the skew and other conditions of the outer needle 20 during movement.

[0141] Refer to Figures 2 to 6 , in some embodiments, two third structural members 221 are provided on the outer needle 20, and the two third structural members 221 are arranged at both ends of the outer needle 20 along the axial direction of the inner needle 10, and the two third structural members 221 respectively abut against the first structural member 30 and the second structural member 51.

[0142] The third structural member 221 refers to the structure on the outer needle 20 for abutting against the first structural member 30; the third structural member 221 can be fixedly connected to the outer needle 20 by welding, bonding, integral molding or other means, or can be detachably connected to the outer needle 20 by screwing, clamping or other means; the third structural member 221 can be a rod-shaped structure, or can be a block-shaped structure or a structure of other shapes; the material of the third structural member 221 can include plastics, metals or other materials.

[0143] There are two third structural members 221, and the two are provided at both ends of the outer needle 20 along the axial direction X of the inner needle 10. For example, the two third structural members 221 can be provided at both ends of the outer needle 20 along the axial direction X of the inner needle 10, and the two third structural members 221 can also be provided on one side of both ends of the outer needle 20 facing the inner needle 10. For example, the third structural member 221 is located on the side of the outer needle 20 facing the inner needle 10, that is, the third structural member 221 is located inside the coiling needle 100, so that the side of the outer needle 20 facing the outside world can be relatively smooth, thereby reducing the damage to the electrode assembly during the process of winding the electrode assembly around the coiling needle 100.

[0144] When the coiling needle 100 includes a first structural member 30 and a second structural member 51, and the first structural member 30 and the second structural member 51 are respectively located at opposite ends of the inner needle 10 along its axial direction X, the two third structural members 221 are respectively located at both ends of the outer needle 20 along the axial direction X of the inner needle 10, which can enable the two third structural members 221 to respectively abut against the first structural member 30 and the second structural member 51. At this time, the outer needle 20 has two supporting parts, so that the outer needle 20 can move relatively stably and is not prone to skew and other situations.

[0145] In this embodiment, two third structural members 221 are provided on the outer needle 20 and respectively abut against the first structural member 30 and the second structural member 51, so that both the first structural member 30 and the second structural member 51 can support the outer needle 20 through the third structural member 221, thereby increasing the stability of the outer needle 20 during the movement process and reducing the situations such as skew of the outer needle 20 during the movement process.

[0146] Reference Figures 2 to 6 , in some embodiments, both of the two third structural members 221 include a third inclined surface 2211. One of the two third inclined surfaces 2211 is parallel to the adjacent first inclined surface 31 and abuts against the first inclined surface 31, and the other of the two third inclined surfaces 2211 is parallel to the adjacent second inclined surface 511 and abuts against the second inclined surface 511.

[0147] The third inclined surface 2211 refers to the inclined surface provided on the third structural member 221. The third inclined surface 2211 is parallel to the first inclined surface 31, and the third inclined surface 2211 abuts against the first inclined surface 31, so that the movement of the first structural member 30 along the axial direction X of the inner needle 10 can push the outer needle 20 to move along the radial direction Y of the inner needle 10 through the first inclined surface 31 and the third inclined surface 2211.

[0148] For example, one ends of the first inclined surface 31 and the third inclined surface 2211 can both face the inside of the coiling needle 100, and the other ends of the first inclined surface 31 and the third inclined surface 2211 can both be inclined along the direction facing the outside of the coiling needle 100 and away from the axis of the inner needle 10; Reference Figure 4, the right ends of the first inclined surface 31 and the third inclined surface 2211 both face the inside of the winding needle 100, and the left ends of the first inclined surface 31 and the third inclined surface 2211 both incline upward to the left. At this time, when the first structural member 30 moves to the right, it can push the outer needle 20 to move upward along the first inclined surface 31 to be away from the inner needle 10.

[0149] Exemplarily, one end of the first inclined surface 31 and the third inclined surface 2211 both faces the inside of the winding needle 100, and the other ends of the first inclined surface 31 and the third inclined surface 2211 can also both incline in the direction facing the outside of the winding needle 100 and close to the axis of the inner needle 10; refer to Figure 5 , the right ends of the first inclined surface 31 and the third inclined surface 2211 both face the inside of the winding needle 100, and the left ends of the first inclined surface 31 and the third inclined surface 2211 both incline downward to the left. At this time, when the first structural member 30 moves to the left, it can push the outer needle 20 to move upward along the first inclined surface 31 to be away from the inner needle 10.

[0150] One of the two third structural members 221 adjacent to the first structural member 30 has the third inclined surface 2211 parallel to the adjacent first inclined surface 31, and this third inclined surface 2211 abuts against the first inclined surface 31 and is in surface contact with the first inclined surface 31; the other of the two third structural members 221 adjacent to the second structural member 51 has the third inclined surface 2211 parallel to the adjacent second inclined surface 511, and this third inclined surface 2211 abuts against the second inclined surface 511 and is in surface contact with the second inclined surface 511; this setting enables both the two third structural members 221 and the first structural member 30 and the second structural member 51 to be in surface contact, so as to further improve the stability of the movement of the third structural member 221 relative to the first structural member 30 and the second structural member 51, thereby being able to further improve the movement stability of the outer needle 20 and reduce the occurrence of situations such as the outer needle 20 being skewed.

[0151] At the same time, the surface contact between the third structural member 221 and the first structural member 30 and the second structural member 51 can also reduce the stress concentration at the contact part, thereby reducing the damage of the first structural member 30, the second structural member 51 and the third structural member 221 and prolonging the service life of the winding needle 100.

[0152] In this embodiment, a third inclined surface 2211 is provided on the third structural member 221, and the two third inclined surfaces 2211 are respectively parallel to the adjacent first inclined surface 31 or the second inclined surface 511, so that the third structural member 221 and the first structural member 30 and the second structural member 51 are in surface contact, thereby being able to increase the contact stability between the third structural member 221 and the first structural member 30 and between the third structural member 221 and the second structural member 51, and thus being able to further increase the stability during the movement of the outer needle 20 and reduce the occurrence of situations such as the outer needle 20 being skewed during the movement.

[0153] Refer to Figure 2 、 Figure 3, in some embodiments, the first structural member 30 is fixedly connected to the inner needle 10; the winding needle 100 further includes a driving assembly 60, and the driving assembly 60 is configured to drive the inner needle 10 to move along the axial direction of the inner needle 10, so as to push the outer needle 20 to move radially away from the inner needle 10 through the first structural member 30.

[0154] The driving assembly 60 refers to the structure in the winding needle 100 for driving the inner needle 10 to move. The driving assembly 60 may include a cylinder, an electric telescopic cylinder or other linear feed structures, and may also include a gear-rack structure in cooperation with a motor, a crank-slider structure in cooperation with a motor or other structures.

[0155] The driving assembly 60 may be disposed inside the winding needle 100 or outside the winding needle 100; for example, the driving assembly 60 is disposed on one side outside the winding needle 100 along the axial direction of the inner needle 10.

[0156] The first structural member 30 is fixedly connected to the inner needle 10 so that the driving assembly 60 driving the inner needle 10 to move can drive the first structural member 30 to move synchronously; since the size of the winding needle 100 is usually small, this setting enables the driving assembly 60 to be disposed outside the winding needle 100 instead of inside the winding needle 100, thereby reducing the layout difficulty of the driving assembly 60 and also reducing the requirement for the internal space of the winding needle 100.

[0157] In this embodiment, the driving assembly 60 drives the inner needle 10 to move, and drives the first structural member 30 to move through the inner needle 10, so that the first structural member 30 can push the outer needle 20 to move, thereby achieving the effect of adjusting the outer diameter of the winding needle 100.

[0158] Reference Figure 2 、 Figure 3 , in some embodiments, an air inlet hole 211 is formed in the outer needle 20; at least two outer needles 20 can enclose an air flow space 201, the air flow space 201 is communicated with the air inlet hole 211, and the air flow space 201 is used to be communicated with an air extraction device to form a negative pressure in the air flow space 201.

[0159] The air inlet hole 211 refers to the hole structure formed in the outer needle 20, and the gas outside the winding needle 100 can enter the inside of the winding needle 100 through the air inlet hole 211; the air inlet hole 211 may be a square hole, a circular hole or other shaped hole structures, and the air inlet hole 211 may be a straight hole, a stepped hole, a tapered hole or other shaped hole structures; there may be one air inlet hole 211, or two or more air inlet holes 211. In the case where there are two or more air inlet holes 211, the plurality of air inlet holes 211 may be uniformly arranged in an array on the outer needle 20 or irregularly arranged on the outer needle 20.

[0160] At least two outer needles 20 can enclose an air flow space 201, and the inner needle 10 is within the air flow space 201; according to the shape of the outer needle 20, the air flow space 201 can be a cylindrical space, a prismatic space or a space of other shapes; the air flow space 201 is communicated with the air inlet hole 211 so that the gas outside the coiling needle 100 can enter the air flow space 201 through the air inlet hole 211.

[0161] The air flow space 201 is used to be connected with an air extraction device, and the air extraction device refers to a structure for extracting the gas in the air flow space 201 to the outside of the coiling needle 100. The air extraction device can include a blower, a vacuum pump or other structures capable of transporting gas.

[0162] The air extraction device can be arranged in the air flow space 201 or outside the coiling needle 100; for example, the air extraction device is arranged outside the coiling needle 100.

[0163] The air extraction device can extract the gas in the air flow space 201 to the outside of the coiling needle 100 and form a negative pressure in the air flow space 201; when the electrode assembly is not covered on the coiling needle 100, the air extraction device can extract the gas outside the coiling needle 100 from the air inlet hole 211 into the air flow space 201 and extract the gas in the air flow space 201 to the outside of the coiling needle 100; when the electrode assembly covers at least a part of the coiling needle 100, the negative pressure formed by the air extraction device can adsorb the part of the electrode assembly in contact with the coiling needle 100 on the outer needle 20, thereby fixing the corresponding part of the electrode assembly.

[0164] It can be understood that the movement of the outer needle 20 along the radial direction Y of the inner needle 10 may cause a gap between adjacent outer needles 20. However, due to the relatively small outer diameter requirement of the coiling needle 100, the moving distance of the outer needle 20 is also small, and the gap between adjacent outer needles 20 is also small. By increasing the power of the air extraction device, the coiling needle 100 can still adsorb the electrode assembly on the coiling needle 100 better; at the same time, due to the coiling of the electrode assembly, the electrode assembly can cover most of the gap between adjacent outer needles 20, thereby further reducing the damage of the negative pressure.

[0165] In this embodiment, the air extraction device can extract the air in the air flow space 201 to the outside of the coiling needle 100 to form a negative pressure in the air flow space 201, and the negative pressure in the air flow space 201 can adsorb the electrode assembly near the air inlet hole 211 on the outer needle 20 to achieve the effect of fixing the electrode assembly.

[0166] Reference Figure 2 、 Figure 3 In some embodiments, there are at least two air inlet holes 211, and the at least two air inlet holes 211 are uniformly arranged on the outer needle 20.

[0167] There are at least two air inlets 211, that is, the number of air inlets 211 can be two, or three or more.

[0168] When the electrode assembly is adsorbed on the winding needle 100 under the action of negative pressure, the main stress part of the electrode assembly is the part near the air inlet 211; accordingly, arranging the air inlets 211 evenly on the outer needle 20 can make the stress of the electrode assembly more uniform, thereby reducing the deformation and other situations that may be caused by local concentrated stress of the electrode assembly, and also enabling the electrode assembly to be better adsorbed and attached to the outer needle 20, thereby reducing the occurrence of situations such as folding due to insufficient local stress of the electrode assembly.

[0169] In this embodiment, there are at least two air inlets 211, so that there can be at least two positions on the outer needle 20 for adsorbing the electrode assembly, thereby improving the stability of fixing the electrode assembly and improving the fixing effect; arranging at least two air inlets 211 evenly, so that the adsorption force received by the electrode assembly can be relatively uniform, thereby reducing abnormal deformations and the like that may be caused by uneven stress of the electrode assembly.

[0170] Reference Figure 2 、 Figure 3 In some embodiments, the aperture range of the air inlet 211 is 1 mm (millimeter) to 2 mm; for example, the aperture of the air inlet 211 can be 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.8 mm, 2 mm or other values.

[0171] The aperture of the air inlet 211 is the diameter of the air inlet 211. Referring to Figure 3 , the dimension shown as R in the figure is the aperture of the air inlet 211; the aperture of the air inlet 211 in the range of 1 mm to 2 mm enables the negative pressure in the air flow space 201 to not only adsorb the electrode assembly near the air inlet 211, but also not easily cause partial deformation of the electrode assembly or the diaphragm and enter the air inlet 211, thereby reducing damage to the electrode assembly.

[0172] The distance between two adjacent air inlets 211 is 2 mm to 4 mm; for example, the distance between two adjacent air inlets 211 can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm or other values.

[0173] The distance between two adjacent air inlets 211 is set as the distance between the centers of two adjacent air inlets 211. Referring to Figure 3, the dimension shown as W in the figure is the distance between two adjacent intake holes 211; since the strength of the adsorption force of the negative pressure in the air flow space 201 on the electrode assembly is related to the total area of each intake hole 211, the distance between two adjacent intake holes 211 within the range of 2 mm to 4 mm can not only better adsorb the electrode assembly on the outer needle 20, but also enable the outer needle 20 to have a certain strength to reduce the negative impact of the intake holes 211 on the strength of the outer needle 20, and at the same time enable the outer needle 20 to better support the electrode assembly.

[0174] For example, the aperture of the intake hole 211 can be 1 mm, and the distance between two adjacent intake holes 211 can be 2 mm. At this time, the aperture of the intake hole 211 is small, and the adsorption force of the electrode assembly at the position of a single intake hole 211 is small, and the electrode assembly is less likely to deform. At the same time, the number of intake holes 211 is large to adsorb the electrode assembly on the outer needle 20.

[0175] For example, the aperture of the intake hole 211 can be 1.5 mm, and the distance between two adjacent intake holes 211 can be 3 mm. At this time, the aperture of the intake hole 211 becomes larger, the adsorption force of the electrode assembly at the position of a single intake hole 211 increases, and the electrode assembly is not easily deformed, and at the same time, the electrode assembly can be better adsorbed.

[0176] For example, the aperture of the intake hole 211 can be 2 mm, and the distance between two adjacent intake holes 211 can be 4 mm. At this time, the aperture of the intake hole 211 is large, and the adsorption force of the electrode assembly at the position of a single intake hole 211 is large, so that the electrode assembly can be better adsorbed.

[0177] This embodiment provides some aperture ranges and spacing ranges of the intake holes 211 so that the intake holes 211 can not only stably adsorb the electrode assembly, but also reduce the situation that the electrode assembly or the diaphragm enters the intake holes 211 and causes the electrode assembly to deform.

[0178] In some embodiments, the range of the negative pressure is -50 KPa (kilopascals) to -75 KPa; for example, the range of the negative pressure can be -50 KPa, -505 KPa, -60 KPa, -65 KPa, -70 KPa, -75 KPa or other values.

[0179] Since the air pressure outside the coiling needle 100 is normal atmospheric pressure, the greater the absolute value of the negative pressure, the better the adsorption performance of the coiling needle 100 on the electrode assembly; the range of the negative pressure is -50 KPa to -75 KPa, so that the coiling needle 100 can not only stably adsorb the electrode assembly, but also reduce the situation that the electrode assembly or the diaphragm enters the intake holes 211 and causes the electrode assembly to deform.

[0180] Exemplarily, the negative pressure value in the air flow space 201 can be -50 KPa. At this time, the coiling needle 100 can not only better reduce the deformation of the electrode assembly, but also stably adsorb the electrode assembly.

[0181] Exemplarily, the negative pressure value in the air flow space 201 can be -62.5 KPa. At this time, the coiling needle 100 can not only preferably reduce the deformation of the electrode assembly, but also relatively stably adsorb the electrode assembly.

[0182] Exemplarily, the negative pressure value in the air flow space 201 can be -50 KPa. At this time, the coiling needle 100 can not only more stably adsorb the electrode assembly, but also reduce the deformation of the electrode assembly.

[0183] This embodiment provides a range of negative pressure in the air flow space 201, so that the coiling needle 100 can both stably adsorb the electrode assembly and reduce the situation where the electrode assembly or the diaphragm enters the air inlet hole 211 and causes deformation of the electrode assembly.

[0184] Reference Figure 2 、 Figure 3 In some embodiments, an air flow channel 101 communicating with the air flow space 201 is provided on the inner needle 10. One end of the air flow channel 101 is used to communicate with an air extraction device, so as to extract the gas in the air flow space 201 out of the coiling needle 100 through the air flow channel 101.

[0185] The air flow channel 101 refers to a channel structure opened inside the inner needle 10; the air flow channel 101 can be formed by a pipe fitting embedded in the inner needle 10, or can be directly formed by opening a hole structure in the inner needle 10; the air flow channel 101 can be a linear structure or a curved structure; along the radial direction of the air flow channel 101, the cross-sectional shape of the air flow channel 101 can be square, circular or other shapes.

[0186] The air flow channel 101 communicates with the air flow space 201, and one end of the air flow channel 101 is connected to the air extraction device, so that the air extraction device can draw the gas in the air flow space 201 into the air flow channel 101 and extract the gas in the air flow channel 101 out of the coiling needle 100; the end of the air flow channel 101 far from the air extraction device can be directly connected to the air flow space 201, or one or more through holes can be opened on the side wall of the inner needle 10 facing the outer needle 20, so that the air flow channel 101 communicates with the air flow space 201 through the through holes.

[0187] In this embodiment, an air flow channel 101 is provided in the inner needle 10, so that the air extraction device can extract the gas in the air flow space 201 through the air flow channel 101 to form a negative pressure, thereby facilitating the air extraction device to extract the gas from the air flow space 201; since the overall size of the coiling needle 100 is usually small, this setting can also reduce the occupation of the internal space of the coiling needle 100 by the air flow channel 101, thereby reducing the arrangement difficulty of each structure inside the coiling needle 100 and saving space.

[0188] Reference Figure 2 、 Figure 3 , in some embodiments, the outer needle 20 includes a middle portion 21, and end portions 22 are connected to both ends of the middle portion 21 along the axial direction of the inner needle 10, and the end portions 22 abut against the first structural member 30; the air inlet holes 211 are at least provided on the middle portion 21, and the air flow space 201 is at least formed between the middle portions 21 of different outer needles 20.

[0189] The middle portion 21 and the end portions 22 are respectively partial structures of the outer needle 20, and the end portions 22 are arranged at both ends of the middle portion 21 along the axial direction X of the inner needle 10.

[0190] According to the shape of the coiling needle 100, the middle portion 21 can be an arc-shaped sheet structure, a flat sheet structure or a structure of other shapes; the material of the middle portion 21 can include metal, plastic or other materials.

[0191] Since the end portions 22 are arranged at both ends of the middle portion 21 and are mainly used to abut against the first structural member 30 and the second structural member 51, the electrode assembly mainly contacts the middle portion 21 during the winding process. Accordingly, the shape of the end portions 22 can be the same as or similar to that of the middle portion 21, or can be different from that of the middle portion 21; for example, to reduce the damage to the electrode assembly, the shape of the end portions 22 is the same as that of the side wall of the middle portion 21 facing outside the coiling needle 100. In the case where the end portions 22 are connected to the middle portion 21, this setting can reduce the dislocation of the side walls of the end portions 22 and the middle portion 21 at the connection part between the two, thereby reducing the damage to the electrode assembly.

[0192] The end portions 22 can be detachably connected to the middle portion 21 by means of screwing, clamping, etc., or can be fixedly connected to the middle portion 21 by means of welding, bonding, integral molding, etc.; the material of the end portions 22 can include metal, plastic or other materials, and the material of the end portions 22 can be the same as or different from the material of the middle portion 21.

[0193] The air inlet hole 211 is at least opened on the middle part 21, that is, the air inlet hole 211 can be only opened on the middle part 21, or the air inlet hole 211 can be opened on both the middle part 21 and the end part 22; the air flow space 201 is at least formed between the middle parts 21 of different outer needles 20, that is, the air flow space 201 can be only formed between the middle parts 21 of different outer needles 20, or can be formed between the middle part 21 and the end part 22 of different outer needles 20.

[0194] In this embodiment, the outer needle 20 includes a middle part 21 and an end plate, so that the end part 22 can abut against the first structural member 30, facilitating the first structural member 30 to push the outer needle 20 to move; the air inlet hole 211 is opened on the middle part 21, facilitating the coiling needle 100 to fix the electrode assembly near the middle part 21, so that the coiling needle 100 can more stably fix the electrode assembly.

[0195] In some embodiments, the thickness range of the middle part 21 is 5 mm to 8 mm; for example, the thickness of the middle part 21 can be 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm or other values.

[0196] The thickness of the middle part 21 is the dimension of the middle part 21 in the radial direction Y of the inner needle 10; since the middle part 21 is mainly used to provide support for the electrode assembly during the winding process of the electrode assembly, the thickness of the middle part 21 is in the range of 5 mm to 8 mm, so that the middle part 21 can not only have strong strength, but also reduce the space occupation so that the air flow can be smoothly extracted from the air flow space 201 to outside the coiling needle 100, and at the same time, the weight of the outer needle 20 can be reduced.

[0197] For example, the thickness of the middle part 21 can be 5 mm. At this time, the thickness of the middle part 21 is relatively thin, the overall thickness of the coiling needle 100 is lighter, and the air flow space 201 is larger, so that the negative pressure formed by the air extraction device can better adsorb the electrode assembly at each air inlet hole 211.

[0198] For example, the thickness of the middle part 21 can be 6.5 mm. At this time, the thickness of the middle part 21 increases, the strength of the coiling needle 100 increases, and the middle part 21 not only has strong strength, but also can better adsorb the electrode assembly.

[0199] For example, the thickness of the middle part 21 can be 8 mm. At this time, the thickness of the middle part 21 is relatively thick, the strength of the coiling needle 100 is strong, facilitating better support for the electrode assembly wound on the coiling needle 100.

[0200] In some embodiments, the end portion 22 is detachably connected to the middle portion 21. The end portion 22 can be detachably connected to the middle portion 21 by screwing, clamping or other means. For example, the end portion 22 is connected to the middle portion 21 by bolts. The bolt connection portion between the end portion 22 and the middle portion 21 can be located on the side of the outer needle 20 facing the inner needle 10 to reduce the damage to the electrode assembly during the winding process of the outer needle 20 on the electrode assembly.

[0201] Since the end portion 22 abuts against the first structural member 30 and the second structural member 51, and during the winding process of the winding needle 100, the change in the outer diameter of the winding needle 100 may be relatively frequent. In such a case, the wear rate of the end portion 22 is likely to be faster than that of the middle portion 21. The end portion 22 is detachably connected to the middle portion 21 to facilitate the installation, replacement and maintenance of the end portion 22, and also facilitate reducing the maintenance cost of the winding needle 100, and at the same time facilitate the overall assembly of the winding needle 100.

[0202] In some embodiments, a material discharging groove 23 is further formed on the circumferential side surface of the outer needle 20. In the axial direction of the inner needle 10, at least one end of the material discharging groove 23 communicates with the space outside the winding needle 100.

[0203] The material discharging groove 23 refers to a groove structure on the winding needle 100 for accommodating the material taking device. The material discharging groove 23 is formed on the circumferential side surface of the outer needle 20, that is, the opening of the material discharging groove 23 faces outside the winding needle 100. After the electrode assembly is wound on the outer needle 20, the electrode assembly can close the opening of the material discharging groove 23. The length direction of the material discharging groove 23 can be parallel to the axial direction X of the inner needle 10, or can be arranged at an angle with the axial direction X of the inner needle 10. At least one end of the material discharging groove 23 along the axial direction X of the inner needle 10 communicates with the space outside the winding needle 100 to facilitate the material taking device to enter the material discharging groove 23. Along the depth direction of the material discharging groove 23, the cross-sectional shape of the material discharging groove 23 can be square, semi-circular, trapezoidal or other shapes.

[0204] In such a winding needle 100, the material taking device can enter the material discharging groove 23 along the axial direction X of the inner needle 10. The material taking device can also move in a direction away from the axis of the inner needle 10, and can move out of the material discharging groove 23 from the opening to contact the electrode assembly. After the material taking device contacts the electrode assembly, it can continue to move in a direction away from the axis of the inner needle 10 and separate the electrode assembly from the outer needle 20 to facilitate removing the electrode assembly from the outer needle 20.

[0205] In the case where the outer needle 20 is formed by splicing the end portion 22 and the middle portion 21, partial structures of the material discharging groove 23 can be provided on both the end portion 22 and the middle portion 21 to form a complete material discharging groove 23 after the end portion 22 is installed on the middle portion 21.

[0206] Since the winding needle 100 includes at least two outer needles 20, only one blanking groove 23 can be provided on each outer needle 20, or two or more blanking grooves 23 can be provided.

[0207] In this embodiment, a blanking groove 23 is provided on the outer needle 20, so that it is convenient for the blanking device to enter the wound electrode assembly and remove the electrode assembly from the winding needle 100.

[0208] Reference Figures 1 to 6 As shown in, in some embodiments, the winding needle 100 includes an inner needle 10, an outer needle 20, and a second structural member 51.

[0209] There are two outer needles 20, and the two outer needles 20 are circumferentially arranged around the inner needle 10 on the circumferential side of the inner needle 10; the two outer needles 20 can move closer to or away from the inner needle 10, and when the two outer needles 20 move closer to the inner needle 10, they can be attached to each other and form a cylindrical structure; an air flow space 201 is formed between the two outer needles 20.

[0210] The outer needle 20 includes a middle portion 21 and end portions 22 provided at both ends of the middle portion 21 along the axial direction X of the inner needle 10; a third structural member 221 is provided on the end portion 22, and a third inclined surface 2211 is provided on the third structural member 221; a plurality of uniformly arranged intake holes 211 are formed on the middle portion 21, and the intake holes 211 communicate with the air flow space 201.

[0211] Hanging portions are provided on one side of the outer needle 20 facing the inner needle 10, and the elastic member 40 is a rubber ring and surrounds all the hanging portions, that is, the hanging portions can extend into the rubber ring and abut against the inner wall of the rubber ring.

[0212] A first structural member 30 is provided on the inner needle 10, a first inclined surface 31 is provided on the first structural member 30, and the first inclined surface 31 abuts against the third inclined surface 2211, and the inner needle 10 can move along its axial direction X; an air flow channel 101 is formed inside the inner needle 10 along its axial direction X, and the air flow channel 101 communicates with the air flow space 201 through a through hole provided on the inner needle 10, and one end of the air flow channel 101 can extend outside the winding needle 100.

[0213] A second inclined surface 511 is provided on the second structural member 51, and the second inclined surface 511 abuts against another third inclined surface 2211.

[0214] The second structural member 51 is an independent component, the second structural member 51 is provided on the base 50, the base 50 is provided on one side of the winding needle 100 along the axial direction X of the inner needle 10, and the second structural member 51 is provided on the base 50; the movement of the inner needle 10 along its axial direction X can move relative to the base 50; a driving component 60 connected to the inner needle 10 is provided on the base 50, and the driving component 60 can drive the inner needle 10 to move along its axial direction X.

[0215] A cavity 52 is also formed in the base 50. One end of the inner needle 10 extends into the cavity 52 and is in communication with the cavity 52. Moreover, the movement of the inner needle 10 along its axial direction X is not likely to cause one end of the inner needle 10 to escape from the cavity 52. An interface 53 communicating with the cavity 52 is further provided on the base 50, and an external air extraction device can be in communication with the interface 53.

[0216] When the inner needle 10 moves in the direction close to the base 50, it can push the outer needle 20 to move away from the inner needle 10 along the radial direction Y of the inner needle 10 through the first inclined surface 31, the second inclined surface 511, and the third inclined surface 2211, and cause the elastic member 40 to deform. When the inner needle 10 moves in the direction away from the base 50, the first inclined surface 31 and the second inclined surface 511 tend to disengage from the corresponding third inclined surface 2211. At this time, under the action of the elastic member 40, the third inclined surface 2211 abuts against the corresponding first inclined surface 31 or the second inclined surface 511, so as to cause the outer needle 20 to move close to the inner needle 10 along the radial direction Y of the inner needle 10.

[0217] When the external air extraction device is started, the gas in the air flow space 201 can be pumped into the air flow channel 101 through the through hole. The gas in the air flow channel 101 is pumped into the air extraction device through the cavity 52 and the interface 53, and finally discharged into the space outside the winding needle 100, so as to form a negative pressure in the air flow space 201. When the electrode assembly is near the winding needle 100, this negative pressure can adsorb and fix the part of the electrode assembly close to the winding needle 100 on the outer needle 20, thereby facilitating the winding of the electrode assembly and reducing the occurrence of situations such as slippage during the winding process of the electrode assembly.

[0218] In a second aspect, some embodiments of the present application further provide a winding device, including the winding needle 100 provided in some embodiments of the first aspect; the tabs in the electrode assembly wound by the winding device are not easily misaligned, thereby being able to alleviate the situations such as shortened battery life, reduced capacity, and safety risks that may be caused by tab misalignment.

[0219] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A needle coil, characterized in that: include: Internal needle; At least two outer needles surround the inner needle along the circumference of the inner needle, and the outer needles are movably arranged on the circumference of the inner needle along the radial direction of the inner needle; The first structural member is abutted against the outer needle, and the first structural member can move relative to the outer needle along the axial direction of the inner needle to push the outer needle away from the inner needle along the radial direction of the inner needle.

2. The winding needle according to claim 1, characterized in that: The winding needle also includes an elastic member arranged inside the winding needle, one end of the elastic member is connected to the outer needle, and the other end of the elastic member can be connected to the inner needle or another outer needle, and the elastic member is used to apply a force to the outer needle pointing in the direction of the inner needle.

3. The winding needle according to claim 1 or 2, characterized in that: The first structural member includes a first inclined surface, which is inclined relative to the axis of the inner needle and forms a first angle with the axis of the inner needle. The first inclined surface is supported by the outer needle so that the outer needle can move relative to the first structural member along the first inclined surface.

4. The winding needle according to claim 3, characterized in that: The first angle ranges from 40° to 50°.

5. The winding needle according to claim 3 or 4, characterized in that: The length of the first inclined surface ranges from 3 mm to 5 mm.

6. The winding needle according to any one of claims 3 to 5, characterized in that: The winding needle further comprises a second structural member, wherein the second structural member and the first structural member are respectively arranged at opposite ends of the inner needle along the axial direction of the inner needle, and the second structural member at least abuts against the outer needle along the axial direction of the inner needle; The first structural component is capable of moving relative to the second structural component along the axial direction of the inner needle.

7. The winding needle according to claim 6, characterized in that: The second structural member comprises a second inclined surface, the second inclined surface abuts against the outer needle, and a second angle is formed between the second inclined surface and the axis of the inner needle; The projection of the intersection of the plane where the second inclined surface is located and the plane where the first inclined surface is located along the radial direction of the inner needle is located in the middle area of ​​the inner needle.

8. The winding needle according to claim 7, characterized in that: The second angle is equal to the first angle.

9. The winding needle according to claim 7 or 8, characterized in that: Two third structural members are arranged on the outer needle. The two third structural members are arranged at two ends of the outer needle along the axial direction of the inner needle. The two third structural members are respectively supported by the first structural member and the second structural member.

10. The winding needle according to claim 9, characterized in that: The two third structural members each include a third inclined surface, one of the two third inclined surfaces is parallel to the adjacent first inclined surface and abuts against the first inclined surface, and the other of the two third inclined surfaces is parallel to the adjacent second inclined surface and abuts against the second inclined surface.

11. The winding needle according to any one of claims 1 to 10, characterized in that: The first structural member is fixedly connected to the inner needle; The winding needle further comprises a driving assembly, wherein the driving assembly is used to drive the inner needle to move along the axial direction of the inner needle, so as to push the outer needle away from the inner needle along the radial direction of the inner needle through the first structural member.

12. The winding needle according to any one of claims 1 to 11, characterized in that: An air inlet hole is provided on the outer needle; At least two of the outer needles can enclose an airflow space, the airflow space is connected to the air inlet, and the airflow space is used to be connected to the air suction device to form a negative pressure in the airflow space.

13. The winding needle according to claim 12, characterized in that: There are at least two air inlet holes, and at least two air inlet holes are evenly arranged on the outer needle.

14. The winding needle according to claim 13, characterized in that: The aperture range of the air inlet holes is 1 mm to 2 mm, and the distance between two adjacent air inlet holes is 2 mm to 4 mm.

15. The winding needle according to any one of claims 12 to 14, characterized in that: The negative pressure ranges from -50KPa to -75KPa.

16. The winding needle according to any one of claims 12 to 15, characterized in that: An air flow channel connected to the air flow space is provided on the inner needle, and one end of the air flow channel is used to be connected to the air extraction device to extract the gas in the air flow space to the outside of the winding needle through the air flow channel.

17. The winding needle according to claim 12, characterized in that: The outer needle comprises a middle portion, both ends of the middle portion along the axial direction of the inner needle are connected to end portions, and the end portions are abutted against the first structural member; The air inlet hole is at least opened on the middle portion, and the air flow space is at least formed between the middle portions of different outer needles.

18. The winding needle according to claim 17, characterized in that: The thickness of the middle portion ranges from 5 mm to 8 mm.

19. The winding needle according to claim 17 or 18, characterized in that: The end portion is detachably connected to the middle portion.

20. The winding needle according to any one of claims 1 to 19, characterized in that: A feeding groove is also provided on the peripheral side of the outer needle; In the axial direction of the inner needle, at least one end of the feed trough is communicated with the space outside the winding needle.

21. A winding device, characterized in that: Comprising the winding needle as described in any one of claims 1-20.

Images