A winding device and a method for winding a material

Abstract

The embodiments of the present application relate to the technical field of battery manufacturing, and in particular to a winding device and a method for winding materials. The winding device is used for winding materials, and includes a roll-changing mechanism, a composite mechanism, and a cutting mechanism. Among them, the roll-changing mechanism includes a turntable and a plurality of winding needles spaced on the turntable, and the material is wound around one of the winding needles along a preset path; the composite mechanism is arranged upstream of the winding needle along the preset path and is used to stack and composite multiple layers of materials together at a preset position; the cutting mechanism is arranged between the composite mechanism and any one of the winding needles along the preset path and is used to cut the composite multi-layer materials from the composite area. Using the winding device and the method for winding materials provided by the embodiments of the present application can prevent the multi-layer materials from delaminating at the moment of being cut and after being cut, thereby avoiding or reducing the occurrence of misalignment problems between the multi-layer materials.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of battery manufacturing, and in particular to a winding device and a method for winding materials. Background Art

[0002] Lithium batteries have the advantages of light weight, large energy storage, high power, stable discharge performance, and long service life, and are widely used in the fields of electric bicycles and new energy vehicles. The electrode assembly is the most important component inside the battery, and the quality of the electrode assembly directly affects the performance of the battery.

[0003] During the battery production process, a winding device is required to wind the electrode sheet and the separator film to form a core. As the prototype of the electrode assembly, the core can be processed into a flat shape, a triangular shape, or other shapes according to requirements to be installed in a housing to make a battery cell. It can be seen that in the production process of the wound electrode assembly, the winding process is an indispensable step. In the winding process, the most important thing is to ensure the alignment between multiple layers of separator films, so as to ensure that when the electrode sheets are sandwiched between the separator films, the positive electrode sheet and the negative electrode sheet do not directly contact at any position, thereby preventing the battery cell from short-circuiting.

[0004] However, during the production process, it is often inevitable that the misalignment problem occurs between multiple layers of separator films, especially the misalignment at the head and tail ends of the core is more obvious, which seriously affects the quality of the battery. Therefore, how to avoid or reduce the misalignment problem at the head and tail ends of the core is an urgent problem to be solved in the process of manufacturing the electrode assembly. Summary of the Invention

[0005] In view of the above problems, the embodiments of the present application provide a winding device and a method for winding materials, which can reduce or even avoid the misalignment of multiple layers of materials at the head and tail ends of the core after cutting.

[0006] According to one aspect of the embodiments of the present application, a winding device is provided. The winding device is used for winding materials, and includes a roll change mechanism, a compounding mechanism, and a cutting mechanism. Among them, the roll change mechanism includes a turntable and a plurality of winding needles spaced on the turntable, and the material is wound around one of the winding needles along a preset path; the compounding mechanism is arranged upstream of the winding needle along the preset path and is used to stack and compound multiple layers of materials together at a preset position; the cutting mechanism is arranged between the compounding mechanism and any one of the winding needles along the preset path and is used to cut the compounded multiple layers of materials from the compounding area.

[0007] By adopting the above solution, a composite mechanism is arranged upstream of the winding needle, and the composite mechanism is used to stack and composite multiple layers of materials at a preset position, so that among the two ends formed after the cutting mechanism cuts the materials from the composite area, the multiple layers of materials at each end are relatively fixed to each other, thereby avoiding delamination of the multiple layers of materials at the moment of cutting and after cutting, and further avoiding the situation that the ends of each layer of materials are misaligned. In addition, since the cutting mechanism cuts the materials from the composite area, during the cutting process, even if the layers of materials are cut successively rather than simultaneously, the first cut layer of materials will not immediately rebound due to the composite relationship with other layers of materials, thereby avoiding the individual rebound of each layer of materials caused by inconsistent cutting order, and further avoiding the problem of misalignment of the multiple layers of materials under the impact of the resilience force.

[0008] In some embodiments, the composite mechanism includes a first hot melt member and a second hot melt member that are opposite and spaced apart, and a driving assembly. The material passes between the first hot melt member and the second hot melt member; the driving assembly is connected to the first hot melt member and / or the second hot melt member to drive the first hot melt member and the second hot melt member to approach each other, so as to adhesively composite the multiple layers of materials by hot pressing.

[0009] By adopting the above solution, when the multiple layers of materials are transported along the preset path, the multiple layers of materials are clamped between the first hot melt member and the second hot melt member as they approach each other, and the multiple layers of materials are clamped and heat-melted from both sides, so that the multiple layers of materials can be quickly heated and pressed to undergo adhesive composite.

[0010] In some embodiments, a plurality of convex portions are spaced on the surface of the first hot melt member and / or the second hot melt member, and the convex portions are configured to abut against the material to melt a plurality of spaced holes in the material.

[0011] By adopting the above solution, during the process of the first hot melt member approaching the second hot melt member, the convex portions first come into contact with the material, and the convex portions abut against the material more tightly. In this case, the material at the corresponding position of the convex portion is heated for a longer time and is more easily melted. And because the material at the corresponding position of the convex portion is abutted more tightly, it is more likely to flow to positions outside the abutting area of the convex portion after being heated and melted, so as to form holes at the corresponding positions of the convex portions, and the multiple layers of materials are adhesively bonded at the edges of the holes, so that it is not easy for the multiple layers of materials to separate and be misaligned.

[0012] In some embodiments, a pre-cut portion is provided between adjacent convex portions, and the protruding height of the pre-cut portion is lower than the protruding height of the convex portions, so as to contact and form a pre-cut position on the material.

[0013] By adopting the above solution, when the first hot melt part and the second hot melt part approach each other, the convex part first abuts against the material, and then the pre-cut part. When the convex part melts holes in the multi-layer material, since the protrusion height of the pre-cut part is lower than that of the convex part, at the corresponding position of the pre-cut part, the material will be pre-divided and squeezed to become thinner, but will not break. Therefore, the pre-cut position is a weak area of the material, and this weak area connects two adjacent holes, making it easier for the cutting mechanism to break the material along the path formed by the pre-cut position and the holes, and the material is not easily deformed during the cutting process.

[0014] In some embodiments, the cutting mechanism is a central shaft roller arranged at the center of the turntable. The central shaft roller is used to tension the material located between any two winding needles and cut the materials laminated together from the pre-cut position.

[0015] By adopting the above solution, since the material breaks at the holes and is relatively weak at the pre-cut position, the central shaft roller only needs to apply a tension force to the material, and it can easily break the material from the pre-cut position, achieving the effect of cutting the material.

[0016] In some embodiments, the laminating mechanism includes a glue coating member for spraying glue between adjacent two layers of materials to laminate the materials.

[0017] By adopting the above solution, the method of laminating multi-layer materials by spraying glue is simpler and easier to implement, and causes less damage to the structure of the material.

[0018] In some embodiments, the cutting mechanism includes a cutter arranged on the turntable. The cutter is used to cut the multi-layer materials laminated together from the lamination area.

[0019] By adopting the above solution, cutting the multi-layer materials with the cutter makes the ends of the cut materials smoother.

[0020] In some embodiments, the cutter is configured to be a heatable cutter.

[0021] By adopting the above solution, the heatable cutter can cut the material by hot cutting, and the cutting speed is faster.

[0022] In some embodiments, the winding device further includes a pressing mechanism arranged on one side of the rotation path of the winding needle along with the turntable, and is used to press against the material located on the winding needle during cutting.

[0023] When the multi-layer materials are cut instantaneously, since the tension is lost, the materials already wound on the winding needle may become loose. By pressing against the materials located on the winding needle with the pressing mechanism, the materials are not easily loosened.

[0024] According to another aspect of the embodiments of the present application, a method for winding a material is provided, including the following steps:

[0025] Wind the multi-layer material around the first winding pin of the rewinding mechanism.

[0026] Stack and laminate the multi-layer material at a preset position.

[0027] Rotate the turntable of the rewinding mechanism to rewind the multi-layer material around the second winding pin, and the composite area of the multi-layer material is located between the first winding pin and the second winding pin.

[0028] Cut the material from the composite area of the multi-layer material.

[0029] By adopting the above solution, since the multi-layer material is pre-compounded together before being cut, in the two ends formed after the material is cut from the composite area, the multi-layer materials at each end are in a relatively fixed state with respect to each other, so it is not easy to delaminate at the moment of being cut and after being cut, avoiding the situation where the layers of the material are misaligned. In addition, since the cutting position of the multi-layer material is located in the composite area, during the cutting process, even if the layers of the material are cut successively rather than simultaneously, the first-cut layer of the material will not immediately rebound due to the composite relationship with other layers of the material, thus avoiding the individual rebound of each layer of the material caused by the inconsistent cutting order, and further avoiding the problem of dislocation of the multi-layer material under the impact of the rebound force.

[0030] In some embodiments, the method of compounding the multi-layer material includes at least one of hot melting, roll pressing, and gluing.

[0031] By adopting the above solution, through hot melting, roll pressing, and gluing, the multi-layer materials can be compounded with each other, and the method is simple and easy to implement.

[0032] In some embodiments, when compounding the multi-layer material, multiple compoundings are performed along the transmission direction of the material.

[0033] By adopting the above solution, it is possible to prevent the situation of poor compounding when only one compounding is performed. In addition, when multiple compoundings are performed on the material, the composite area includes the outermost two composite positions along the transmission direction and the area therebetween. Therefore, the area of the composite area is greatly increased. During the subsequent cutting process, the cutting position can be located at any position in the composite area, and the available cutting area is increased, reducing the positioning difficulty during the operation of the cutting mechanism.

[0034] In some embodiments, when cutting the material from the composite area of the multi-layer material, the cutting position is located at any one composite position or between any two composite positions.

[0035] Regardless of whether the breaking position is at any one composite position or between any two composite positions, it can ensure that among the two ends formed after breaking the material, the layers of the material are in a composite state, thus preventing the dislocation problem caused by the delamination of the layers of the material.

[0036] In some embodiments, when using hot melt to composite multiple layers of material, the composite method includes: melting out a plurality of spaced holes on the material, and the multiple layers of material are adhesively combined at the edges of the holes. The method of breaking the material from the composite area of the multiple layers of material includes: rotating the first winding needle and / or the second winding needle to break the material between the plurality of spaced holes.

[0037] By adopting the above scheme, holes are made on the multiple layers of material by hot melt, and the multiple layers of material are adhesively combined at the edges of the holes and are not easily separated. On the alignment line of the holes, the material is only connected through the spaced areas between the holes, so the connection is relatively weak. When the first winding needle and / or the second winding needle rotates, the material between the first winding needle and the second winding needle is subjected to a large tension and breaks from the relatively weak position, that is, the material breaks between the plurality of spaced holes, realizing the breaking of the material without using a tool, with a simple structure and high operation efficiency.

[0038] In some embodiments, when using hot melt to composite multiple layers of material, the composite method further includes: melting and forming a pre-cut position between the plurality of spaced holes, and the multiple layers of material are adhesively combined at the pre-cut position. The method of breaking the material from the composite area of the multiple layers of material further includes: rotating the first winding needle and / or the second winding needle to break the material from the pre-cut position between the plurality of spaced holes.

[0039] By adopting the above scheme, the pre-cut position is a weak area of the material, and this weak area connects two adjacent holes, so that when the first winding needle and / or the second winding needle rotates, the material between the first winding needle and the second winding needle is more likely to break along the connection line of the pre-cut position and the hole after being subjected to tension, and the material is not easily deformed during the breaking process.

[0040] According to the third aspect of the embodiments of the present application, a core is provided. The core is wound by multiple layers of material, and a composite part is provided on the multiple layers of material. The multiple layers of material are laminated and combined together at the composite part. In the winding direction, there is a predetermined distance between the composite part and the end of the material; the end is one end of the material at the innermost circle in the winding direction, or the end is one end of the material at the outermost circle in the winding direction.

[0041] In some embodiments, there are multiple composite parts, and the multiple composite parts are spaced apart.

[0042] In some embodiments, the multiple layers of material are combined together at the composite part by means of hot melt composite and / or roll press composite and / or adhesive composite.

[0043] In some embodiments, when the end portion is the end of the material at the innermost circle in the winding direction, the predetermined distance is less than the circumference of the innermost circle of the core.

[0044] In some embodiments, when the end portion is the end of the material at the outermost circle in the winding direction, the predetermined distance is less than the circumference of the outermost circle of the core. In summary, for the winding device provided by the embodiments of the present application, by arranging a composite mechanism upstream of the winding needle and using the composite mechanism to stack and composite multiple layers of materials together, among the two end portions formed after the breaking mechanism breaks the material from the composite area, the multiple layers of materials at each end portion are in a relatively fixed state with respect to each other, so that it is not easy to delaminate during and after the moment of being broken, and the situation of misalignment between the layers of materials is avoided.

[0045] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to be able to understand the technical means of the embodiments 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 embodiments of the present application more obvious and understandable, the following specifically illustrates the specific embodiments of the present application. Description of the Drawings

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0047] Figure 1 It is a schematic structural diagram of a winding device in an embodiment of the present application.

[0048] Figure 2 It is a schematic structural diagram of a composite area on a material in an embodiment of the present application.

[0049] Figure 3 It is another schematic structural diagram of a composite area on a material in an embodiment of the present application.

[0050] Figure 4 It is a schematic structural diagram of a composite mechanism in an embodiment of the present application.

[0051] Figure 5 It is the structure of a first hot melt part in an embodiment of the present application.

[0052] Figure 6 It is another schematic structural diagram of a first hot melt part in an embodiment of the present application.

[0053] Figure 7 For Figure 6 the top view of the first hot melt part in

[0054] Figure 8 Schematic diagram of the material after being compounded by the compound mechanism in the embodiment of the present application.

[0055] Figure 9 Schematic diagram of the state where the material after being compounded by the compound mechanism in the embodiment of the present application is segmented.

[0056] Figure 10 Schematic diagram of the structure of the winding device in another embodiment of the present application.

[0057] Figure 11 Schematic diagram of the structure of the winding device in an embodiment of Li Zhongde of the present application.

[0058] Figure 12 Flowchart of a method for winding a material disclosed in the embodiment of the present application.

[0059] Figure 13 Flowchart of the second method for winding a material disclosed in the embodiment of the present application.

[0060] Figure 14 Flowchart of the third method for winding a material disclosed in the embodiment of the present application.

[0061] Figure 15 Flowchart of the fourth method for winding a material disclosed in the embodiment of the present application.

[0062] Figure 16 Flowchart of the fifth method for winding a material disclosed in the embodiment of the present application.

[0063] Figure 17 Schematic diagram of the structure of a core disclosed in the embodiment of the present application.

[0064] Figure 18 Schematic diagram of the structure of another core disclosed in the embodiment of the present application.

[0065] [[ID=**44**]]Explanation of reference numerals: 1. Rewinding mechanism; 11. Turntable; 12. Winding needle; 2. Compound mechanism; 21. First hot melt part; 22. Second hot melt part; 23. Driving component; 24. Convex part; 25. Pre-cut part; 26. Glue-applying component; 3. Cutting mechanism; 31. Central shaft roller; 32. Cutter; 4. Pressing mechanism; 41. Extrusion part; 42. Driving part; 5. Material; 51. Compound area; 52. Compound position; 53. Hole; 54. Pre-cut position; 6. Core; 61. Compound part. Detailed implementation manners

[0066] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Apparently, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without making creative efforts shall fall within the scope of protection of this application.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the description of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0068] The terms "including" and "having" and any variations thereof in the description and claims of this application and the accompanying drawings are intended to cover but not exclude other elements. The word "a" or "an" does not exclude the presence of a plurality.

[0069] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of this application. The phrase "embodiments" appearing in various places in the description is not necessarily referring to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0070] The term "and / or" herein is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0071] The orientation terms appearing in the following description are all the directions shown in the figures and do not specifically limit the structure of the winding device of this application. For example, in the description of this application, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this 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, and therefore cannot be construed as a limitation of this application.

[0072] In addition, the terms "first", "second", etc. in the description and claims of this application or in the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order, and may explicitly or implicitly include one or more of such features.

[0073] In the description of this application, unless otherwise specified, the meaning of "a plurality" refers to more than two (including two). Similarly, "a plurality of groups" refers to more than two groups (including two groups).

[0074] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, the "connection" or "coupling" of a mechanical structure may refer to a physical connection. For example, a physical connection may be a fixed connection, such as a fixed connection through a fixing member, such as a screw, bolt, or other fixing member; a physical connection may also be a detachable connection, such as a snap connection or a snap-fit connection; a physical connection may also be an integral connection, such as a connection formed by welding, bonding, or integral molding. The "connection" or "coupling" of a circuit structure may refer to not only a physical connection but also an electrical connection or a signal connection. For example, it may be a direct connection, that is, a physical connection, or it may be indirectly connected through at least one intermediate element, as long as the circuit is connected. It may also be the communication inside two components; a signal connection may refer to not only a signal connection through a circuit but also a signal connection through a media medium, such as radio waves. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0075] The electrode assembly is the most important component of a battery cell. The electrode assembly includes a stacked structure and a wound structure. Among them, in the wound structure, the electrode assembly is generally wound by a positive electrode sheet, a negative electrode sheet, and a separator. The separator is sandwiched between the positive electrode sheet and the negative electrode sheet to prevent the positive electrode sheet from directly contacting the negative electrode sheet and causing a short circuit.

[0076] During the battery production process, a winding device is required to wind the electrode sheet and the separator to form a core. The core, as the prototype of the electrode assembly, can be processed into a flat shape, a triangular shape, or other shapes according to requirements to be installed in a housing to make a battery cell.

[0077] However, during the production process, it is often inevitable that misalignment occurs between multiple layers of separators, especially at the head and tail ends of the core, which seriously affects the quality of the battery.

[0078] The inventor studied the forming process of the core and found that the winding of the core is generally completed by a turret. The turret generally includes a turntable with a rotating shaft at the center and workstations for setting winding needles at the edge. During the winding process, the winding needle can pre-wind a certain number of layers of separator film, then send the electrode sheet to the winding needle, and finally wind the electrode sheet and the separator film together with the winding needle to form a core. When a core is about to be wound, the electrode sheet feeding mechanism first cuts the electrode sheet. After the turntable rotates, the workstation where the winding needle with the wound core is located is rotated out of the winding position, and the winding needle on another workstation is rotated to the winding position. After the separator film is switched to a new winding needle, the cutting mechanism is used to cut the separator film between the two winding needles. Among the two ends formed after cutting, one end serves as the tail end of the previous core, and the other serves as the head end of the next core.

[0079] Through long-term observation, the inventor found that at the moment when the multi-layer separator film is cut, each layer of the separator film will rebound to varying degrees. It is precisely because the degrees and directions of rebound of each layer of the separator film are different that the problem of misalignment occurs between each layer of the separator film. The reason why the degrees and directions of rebound of each layer of the separator film are different is that during the cutting process, the separator film closer to the cutting knife is disconnected first, and the separator film farther from the cutting knife is disconnected last. Therefore, the cutting sequence of each layer of the separator film is different. The one cut first rebounds first, and the one cut later rebounds later, ultimately resulting in misalignment between each layer of the separator film.

[0080] In view of this, the embodiments of the present application provide a winding device and a method for winding materials. By setting a composite mechanism upstream of the cutting mechanism and the winding needle, before cutting the separator film, the multi-layer separator film is first compounded and bonded to each other, so that the multi-layer separator film is separated from the composite area at the cutting mechanism. At this time, due to the composite relationship between each layer of the separator film, it is possible to prevent the situation where the degrees and directions of rebound of the separator film are different due to different cutting sequences of each layer of the separator film, thereby effectively avoiding or reducing the misalignment of the multi-layer separator film at the head end and the tail end of the core after cutting.

[0081] The winding device and the method for winding materials disclosed in the present application are not limited to the core forming in the battery manufacturing process, but can also be applied to other manufacturing processes where misalignment between multi-layer materials needs to be avoided. Therefore, the products to be wound hereinafter are collectively referred to as materials.

[0082] Figure 1 is a schematic structural diagram of a winding device in the embodiments of the present application, as Figure 1As shown in the figure, the winding device includes a roll-changing mechanism 1, a compounding mechanism 2, and a cutting mechanism 3. Among them, the roll-changing mechanism 1 includes a turntable 11 and a plurality of winding needles 12 spaced on the turntable 11. The material 5 is wound around one of the winding needles 12 along a preset path. The compounding mechanism 2 is arranged upstream of the winding needle 12 along the preset path and is used to stack and compound multiple layers of the material 5 together at a preset position. The cutting mechanism 3 is arranged between the compounding mechanism 2 and any one of the winding needles 12 along the preset path and is used to cut the compounded multiple layers of the material 5 from the compounding area 51.

[0083] Among them, the turntable 11 can be a disc or a disc of other shapes. The turntable 11 includes a side surface and two end surfaces. The turntable 11 can rotate around an axis perpendicular to the end surface under the action of any driving device. The winding needles 12 are located on the end surface of the turntable 11. When the roll-changing mechanism 1 works, the turntable 11 generally only needs to rotate during roll-changing. That is, multiple layers of the material 5 enter one side of the turntable 11 along the preset path and are wound around the winding needle A on one of the winding stations. When the number of layers of the material 5 wound on the winding needle A reaches the preset number of layers, or the thickness of the material 5 wound on the winding needle A reaches the preset thickness, the turntable 11 is rotated so that the winding needle A rotates with the turntable 11 to the unloading station. At the same time, another winding needle B rotates with the turntable 11 to the winding station, and the material 5 is switched to the winding needle B to continue winding. The material 5 on the winding needle A is taken off at the unloading station, thus completing one roll change.

[0084] Optionally, the distance between each winding needle 12 and the rotation axis of the turntable 11 can be equal or unequal. When the distances between multiple winding needles 12 and the rotation axis of the turntable 11 are equal, during the process of roll-changing by the rotation of the turntable 11 itself, each winding needle 12 can stay at the same winding station or the winding-up station during one roll change, so that the material 5 can be switched from one winding needle 12 to another without changing the preset path of the material 5.

[0085] Optionally, the degrees of the angles formed by the connections between any two adjacent winding needles 12 and the rotation axis of the turntable 11 are equal. In this way, every time the turntable 11 rotates a fixed angle, one winding needle 12 can stay at a fixed winding-up station, and another winding needle 12 can stay at a fixed winding-up station, improving the efficiency of batch operation.

[0086] The R direction in the figure represents the rotation direction of the winding needle 12 when winding the material. In actual production, the rotation direction of the winding needle can also be different from that in the figure. The embodiments of the present application do not limit this.

[0087] The composite mechanism 2 is arranged on the preset path of the material 5, so as to stack and composite multiple layers of the material 5 together at a preset position when the material 5 passes by. Wherein, the preset position refers to the position of the end or the head of the preset core 6. For example, after estimating the total length L of the material 5 required for a core 6, starting from when the material 5 begins to wind around the winding needle A, a section of the material 5 after winding around the winding needle A by a length of L, or a section of the material 5 that is about to reach the length of L and after the length of L can be used as the preset position, and multiple layers of the material 5 are stacked and composite at this preset position. Among them, the composite mechanism 2 can act from one side of the multi-layer stacked material 5, or from both sides of the multiple layers of the material 5, or from between two adjacent layers of the material 5, and the embodiments of the present application do not limit this.

[0088] Wherein, the upstream of the winding needle 12 refers to the direction of the material 5 entering the winding station of the winding needle 12. That is to say, before the material 5 enters the winding station, the composite mechanism 2 has completed the composite of the material 5 at the preset position.

[0089] The cutting mechanism 3 can cut, break or fuse multiple layers of the material 5 from the composite area 51, so that among the two ends formed by the material 5 at the disconnection position, the multiple layers of the material 5 at any one end are in a connected state. Among them, as Figure 2 shown, when the composite mechanism 2 forms a continuous composite position 52 on the material 5 along the transmission direction, the composite area 51 refers to the area between the two boundaries of the composite position 52 along the transmission direction. As Figure 3 shown, when the composite mechanism 2 forms multiple spaced composite positions 52 on the material 5 along the transmission direction, the composite area 51 can be the area between the mutually distant boundaries of the two outermost composite positions 52 along the transmission direction.

[0090] In the above embodiments of the present application, by arranging the composite mechanism 2 upstream of the winding needle 12 and using the composite mechanism 2 to stack and composite multiple layers of the material 5 together at the preset position, among the two ends formed after the cutting mechanism 3 cuts the material 5 from the composite area 51, the multiple layers of the material 5 at each end are in a relatively fixed state with respect to each other, so that it is not easy to delaminate at the moment of being cut and after being cut, and the situation of misalignment between the layers of the material 5 is avoided. In addition, since the cutting mechanism 3 cuts the material 5 from the composite area 51, during the cutting process, even if the layers of the material 5 are cut successively rather than simultaneously, the first cut layer of the material 5 will not immediately rebound due to the composite relationship with other layers of the material 5, thus avoiding the individual rebound of each layer of the material 5 caused by inconsistent cutting order between the layers of the material 5, and further avoiding the problem of misalignment of the multiple layers of the material 5 under the impact of the resilience force.

[0091] AsFigure 4 As shown, in some embodiments, the composite mechanism 2 includes a first hot-melting member 21 and a second hot-melting member 22 that are opposite and spaced apart, and a driving assembly 23. The material 5 passes through between the first hot-melting member 21 and the second hot-melting member 22. The driving assembly 23 is connected to the first hot-melting member 21 and / or the second hot-melting member 22 to drive the first hot-melting member 21 and the second hot-melting member 22 to approach each other, so as to adhesively compound the multi-layer material 5 by hot pressing.

[0092] The structures of the first hot-melting member 21 and the second hot-melting member 22 may be the same or different, and they may be hot-pressing rollers, hot-sealing heads or hot-pressing flat plates, etc. In some embodiments, the heating methods of both the first hot-melting member 21 and the second hot-melting member 22 may be electric heating, so that the hot-melting temperature is easier to control. Of course, in other embodiments, the heating methods of the first hot-melting member 21 and the second hot-melting member 22 may also be other heating methods, and the embodiments of the present application do not limit this.

[0093] The driving assembly 23 may be connected only to the first hot-melting member 21 or the second hot-melting member 22, or may be connected to both the first hot-melting member 21 and the second hot-melting member 22 at the same time. Correspondingly, the way for the driving assembly 23 to drive the first hot-melting member 21 and the second hot-melting member 22 to approach each other may be to drive the first hot-melting member 21 to approach the second hot-melting member 22, or to drive the second hot-melting member 22 to approach the first hot-melting member 21, or to drive the first hot-melting member 21 and the second hot-melting member 22 to move towards each other at the same time. The structure of the driving assembly 23 can be various. For example, the driving assembly 23 includes one or more of a linear motor, a cylinder, a hydraulic cylinder, a lead screw-nut mechanism and a worm and worm gear mechanism. The ways of driving the components to move in the above structures are the same as those in the prior art, and the driving principles and ways thereof are not described in detail in the embodiments of the present application.

[0094] By adopting the above solution, when the multi-layer material 5 is transported along a preset path, the driving assembly 23 drives the first hot-melting member 21 and the second hot-melting member 22 to approach each other, sandwiching the multi-layer material 5 therebetween, and clamping and hot-melting the multi-layer material 5 from both sides, so that the multi-layer material 5 can be quickly heated and pressed to undergo adhesive compounding.

[0095] Figure 5 This is the structure of the first hot-melting member in an embodiment of the present application. As Figure 5 shown, in some embodiments, a plurality of convex portions 24 are spaced apart on the surface of the first hot-melting member 21 and / or the second hot-melting member 22. The convex portions 24 are configured to abut against the material 5 to melt a plurality of spaced holes 53 on the material 5 (see Figure 8 ).

[0096] The convex portion 24 refers to a structure protruding from the surface of the body. For example, if the first hot-melting member 21 and the second hot-melting member 22 are hot-melting rollers or hot pressing plates, then the convex portion 24 can be a protruding part provided on the roller surface of the hot-melting roller or the surface of the hot pressing plate. The shape of the side of the convex portion 24 away from the body can be circular, rectangular or other shapes, so as to hot-melt holes 53 of corresponding shapes on the material 5 (see Figure 8 ).

[0097] The convex portion 24 can be provided on the first hot-melting member 21, or can be provided on the second hot-melting member 22, or the convex portion 24 can be provided on both the first hot-melting member 21 and the second hot-melting member 22. However, when the convex portion 24 is provided on both the first hot-melting member 21 and the second hot-melting member 22, the two convex portions 24 on the first hot-melting member 21 and the second hot-melting member 22 can be provided at positions facing each other. Thus, when the first hot-melting member 21 and the second hot-melting member 22 approach each other, the convex portion 24 first abuts against the material 5 to melt out holes 53 on the material 5. Figure 5 Taking the example of only the convex portion 24 being provided on the first hot-melting member 21 for illustration, it can be understood that the structure of the convex portion 24 provided on the second hot-melting member 22 is the same as or similar to that provided on the first hot-melting member 21.

[0098] The principle of using the convex portion 24 to hot-melt holes 53 on the material 5 is as follows: During the process of the first hot-melting member 21 and the second hot-melting member 22 approaching each other, the convex portion 24 first contacts the material 5, and the convex portion 24 abuts against the material 5 more tightly. In this case, the material 5 at the corresponding position of the convex portion 24 is heated for a longer time and is more easily melted. And because the material 5 at the corresponding position of the convex portion 24 is abutted more tightly, it is more likely to flow to positions outside the abutting area of the convex portion 24 after being heated and melted. Thus, holes 53 are formed at the corresponding positions of the convex portion 24, and the multiple layers of the material 5 are in an adhesive state at the edges of the holes 53, so that it is not easy for the multiple layers of the material 5 to separate or be misaligned. And at the position of the holes 53, the material 5 is more fragile and is more easily cut off, causing less pulling deformation to the part outside the holes 53.

[0099] Figure 6 FIG. is a schematic structural view of another first hot-melting member 21 in an embodiment of the present application, Figure 7 is Figure 6 a top view of the first hot-melting member 21 in Figure 6 and Figure 7 shown. In some embodiments, a pre-cut portion 25 is provided between adjacent convex portions 24. The protruding height of the pre-cut portion 25 is lower than the protruding height of the convex portion 24 to contact and form a pre-cut position 54 on the material 5.

[0100] Optionally, the pre-cutting portion 25 can connect two adjacent convex portions 24, so that a line formed by the holes 53 and the pre-cutting positions 54 can be formed on the material 5 after the first hot melt member 21 and the second hot melt member 22 are abutted, as Figure 8 shown, Figure 8 is the structure of the material after being compounded by the compounding mechanism in the embodiment of the present application. It can be seen that a straight line is formed on the material 5 in the figure by the holes 53 and the pre-cutting positions 54.

[0101] The principle that the pre-cutting portion 25 can form the pre-cutting position 54 is as follows: Since the protruding height of the pre-cutting portion 25 is lower than that of the convex portion 24, when the first hot melt member 21 and the second hot melt member 22 approach, the first to abut the material 5 is the convex portion 24, and then the pre-cutting portion 25. When the convex portion 24 melts out the holes 53 on the multi-layer material 5, since the protruding height of the pre-cutting portion 25 is lower than that of the convex portion 24, the material 5 will be pre-divided at the corresponding position of the pre-cutting portion 25. For example, in one embodiment, the pre-division method can be to set the pre-cutting portion 25 into a structure with a cutting edge, and use the cutting edge to slightly squeeze the material 5 to form a cut mark on the material 5, but the material 5 is not completely cut off. In another embodiment, the pre-division method can be to set the pre-cutting portion 25 into a structure that can be heated. The pre-cutting portion 25 contacts the multi-layer material 5, so that the multi-layer material 5 is melted and squeezed to become thinner, but will not break. The pre-cutting position 54 formed on the material 5 by the above pre-division method is a weak area of the material 5, and this weak area connects two adjacent holes 53.

[0102] Figure 9 is a schematic diagram of the state where the material compounded by the compounding mechanism in the embodiment of the present application is divided, as Figure 8 and Figure 9 shown. Since a straight line is formed on the material 5 by the holes 53 and the pre-cutting positions 54, therefore, during the process of switching the material 5, when one winding pin A and another winding pin B rotate together, the material 5 can be quickly disconnected along the line formed by the holes 53 and the pre-cutting positions 54 under the action of tension. During this process, there is no need to use the cutter 32 for cutting, so the division of the material 5 is faster and more convenient, and the material 5 is not easily deformed during the division process.

[0103] Figure 10 is a schematic structural diagram of a winding device in another embodiment of the present application, as Figure 10 shown. In some embodiments, the dividing mechanism 3 is a central shaft roller 31 provided at the center of the turntable 11. The central shaft roller 31 is used to tension the material 5 located between any two winding pins 12 and divide the materials 5 compounded together from the pre-cutting position 54.

[0104] In the case where the aforementioned composite mechanism 2 includes a protrusion 24 and a pre-cut portion 25, by setting the separating mechanism 3 as a central axis roller 31, the central axis roller 31 is used to apply tension to the material 5, so that the material 5 can be easily disconnected from the connecting line formed by the pre-cut position 54 and the hole 53, thereby achieving the effect of separating the material 5. The structure is simple and there is no need to shut down the equipment during the entire separating process.

[0105] Figure 11 This is a structural diagram of a winding device in another embodiment of the present application, as shown in FIG. Figure 11 As shown, in some embodiments, the composite structure 2 includes a glue-spreading component 26 , which is used to spray glue between two adjacent layers of material 5 to composite the material 5 .

[0106] The glue coating member 26 is disposed between two adjacent layers of material 5 and can spray glue on the side surface of any layer of material 5. In this way, after the multiple layers of material 5 are stacked, they can be connected together by glue to achieve a composite of the multiple layers of material 5. Optionally, the glue connection position can be one or multiple locations along the conveying direction of the material 5.

[0107] By adopting the above solution, the method of compounding the multiple layers of materials 5 by spraying glue is simpler and easier, and the damage to the structure of the materials 5 is less.

[0108] like Figure 11 As shown, in some embodiments, the separating mechanism 3 includes a cutter 32 provided on the turntable 11 , and the cutter 32 is used to cut the composited multi-layer materials 5 from the composite area 51 .

[0109] When the composite mechanism 2 includes a hot melt roller, or a common pressure roller, or a glue coating component 26, or a protrusion 24, a cutter 32 can be used to cut the composite materials 5, thereby ensuring that the materials 5 can be cut quickly and the ends of the cut materials 5 are smoother.

[0110] In some embodiments, the cutter 32 can be used in combination with the center roller 31 in the above embodiments, for example, Figure 11 As shown, a cutter 32 is provided on the central roller 31, and the blade of the cutter 32 faces away from the central roller 31. When the central roller 31 rotates with the turntable 11, the position of the cutter 32 avoids the line connecting the rotation center of the turntable 11 and the center of any winding needle 12. For example, the cutter 32 is located on the bisector of the angle between the two winding needles 12 and the rotation center of the turntable 11; when the material 5 can be switched between any two adjacent winding needles 12, multiple cutters can be provided at different positions of the central roller 31, and each cutter is located on the bisector of the angle between the two adjacent winding needles 12 and the rotation center of the turntable 11. For example, Figure 11As shown, when there are two winding needles 12 provided on the turntable 11, there are two cutting knives 32, and the two cutting knives 32 are respectively located in two included angles formed by the connecting lines between the two winding needles 12 and the rotation center of the turntable 11; when the central shaft roller 31 can rotate relative to the turntable 11, only one cutting knife 32 can be provided. When the material 5 needs to be switched between two winding needles 12, rotate the central shaft roller 31 to rotate the cutting knife 32 into the included angle range between the two winding needles 12 and the rotation center of the turntable 11.

[0111] In some embodiments, the cutting knife 32 can also be fixedly used alone on the turntable 11. For example, directly fix the cutting knife 32 to the end face of the turntable 11 where the winding needle 12 is provided. The number of cutting knives 32 can be one or more, and each cutting knife 32 is located in the included angle formed by the connecting lines between two adjacent winding needles and the rotation center of the turntable 11, so as to contact the material 5 and cut the material 5 when the material 5 is switched between two adjacent winding needles 12.

[0112] In some embodiments, the cutting knife 32 is configured as a heatable cutting knife.

[0113] The heating method of the cutting knife 32 can be electric heating, so as to facilitate the control of the temperature of the cutting knife 32. The whole cutting knife 32 can be heated, or only the blade part of the cutting knife 32 can be heated.

[0114] By adopting the heatable cutting knife 32, the heatable cutting knife 32 can cut the material 5 by hot cutting, and the cutting speed is faster.

[0115] It should be noted that after the material 5 is compounded by applying glue, in order to prevent some glue from adhering to the cutting knife 32 when heated and affecting the sharpness of the cutting knife 32, multiple gluing positions can be provided on the material 5 to generate multiple compounding positions 52, and the adjacent compounding positions 52 are arranged at intervals, and the cutting position of the heatable cutting knife is located between the two compounding positions 52, so that the heatable cutting knife 32 can be prevented from directly contacting the glue to prevent the glue from adhering to the cutting knife 32 after heating.

[0116] [[ID=IS]]In some cases, when the multi-layer material 5 is being severed, since the tension on the material 5 is lost, the core 6 that has been wound around the winding needle 12 may become loose. To avoid the core 6 that has been wound from becoming loose, as Figure 10 and Figure 11 shown, in some embodiments, the winding device further includes a pressing mechanism 4. The pressing mechanism 4 is arranged on one side of the rotation path of the winding needle 12 following the turntable 11, and is used to press against the material 5 located on the winding needle 12 during severance.

[0117] Optionally, the pressing mechanism 4 includes an extrusion member 41. The extrusion member 41 can be of any shape. The surface of the extrusion member 41 that contacts the core 6 is provided as an arc surface or a flat surface to prevent sharp edges from damaging the material 5 on the outer layer of the core 6.

[0118] Optionally, the extrusion member 41 can be a cylindrical pressure roller, and the pressure roller can rotate together with the core 6 while pressing against the core 6. In this way, when the turntable 11 drives the winding needle 12 and the core 6 to rotate, the pressure roller can not only prevent the core 6 from loosening, but also rotate relative to the core 6 to prevent frictional damage to the material 5 on the outer layer of the core 6 when the core 6 rotates.

[0119] Optionally, the pressing mechanism 4 further includes a driving member 42. The driving member 42 drives the extrusion member to move closer to or away from the core 6. For example, when the cutting mechanism 3 cuts the material 5, the driving member 42 drives the extrusion member 41 to approach the core 6 to press the core 6. After the material 5 on the outer layer of the core 6 is fixed, the driving member 42 can drive the extrusion member 41 away from the core 6, so as to facilitate taking away the core 6. The driving member 42 can be a cylinder, a hydraulic cylinder or a linear motor, etc.

[0120] It can be seen that the winding device provided with the pressing mechanism 4 is not likely to cause the core 6 to loosen when cutting the material 5, which is beneficial to ensuring the quality of the core 6 and thus improving the quality of the battery.

[0121] Figure 12 For a flowchart of a method for winding a material, as Figure 12 shown, an embodiment of the present application further provides a method for winding a material, including the following steps:

[0122] S101: Wind multiple layers of the material 5 around the first winding needle on the rewinding mechanism 1.

[0123] S102: Stack and laminate multiple layers of the material 5 at a preset position.

[0124] S103: Rotate the turntable 11 of the rewinding mechanism 1 to wind multiple layers of the material 5 around the second winding needle, and the composite area 51 of the multiple layers of the material 5 is located between the first winding needle and the second winding needle.

[0125] S104: Cut the material 5 from the composite area 51 of the multiple layers of the material 5.

[0126] The method for winding the material can be implemented by the winding device in any of the foregoing embodiments of the first aspect, and the specific structure and usage method of the winding device have been described in detail in the foregoing embodiments of the winding device, and will not be repeated in the embodiments of the present application.

[0127] By adopting the above solution, since the multi-layer material 5 is pre-compounded together before being severed, among the two ends formed after the material 5 is severed from the compounding area 51, the multi-layer materials 5 at each end are in a relatively fixed state with respect to each other, so it is not easy to delaminate at the moment of being severed and after being severed, avoiding the dislocation of the layers of the material 5. In addition, since the severing position of the multi-layer material 5 is located in the compounding area 51, during the severing process, even if the layers of the material 5 are severed successively rather than simultaneously, the first-severed layer of the material 5 will not immediately rebound due to the compounding relationship with other layers of the material 5, thus avoiding the individual rebound of the layers of the material 5 caused by inconsistent severing order, and further avoiding the problem of dislocation of the multi-layer material 5 under the impact of the resilience force.

[0128] In some embodiments, the method of laminating and compounding the multi-layer material 5 at a preset position includes at least one of hot melting, roll pressing, and gluing.

[0129] Hot melting can be achieved by using a hot melt roll, roll pressing can be achieved by relatively squeezing from both sides of the multi-layer material 5 using two pressing rolls, and gluing can be achieved by evenly spraying glue between adjacent layers of the material 5 through high pressure.

[0130] Through hot melting, roll pressing, and gluing, the multi-layer materials 5 can be compounded with each other, and the method is simple and easy to implement.

[0131] As Figure 13 shown, in some embodiments, when laminating and compounding the multi-layer material 5 at a preset position, it specifically includes: S1021: performing multiple compoundings along the transmission direction of the material 5. The flowchart of the method for the wound material after adopting this method is as Figure 13 shown.

[0132] In one implementation, it can be achieved by intermittently approaching, squeezing, moving away, approaching, squeezing, and moving away with a hot melt roll or a pressing roll.

[0133] In another implementation, it can be achieved by intermittently ejecting glue with a gluing member 26.

[0134] By adopting the above solution, it is possible to prevent the situation of poor compounding when only one compounding is performed. In addition, after multiple compoundings are performed on the material 5, the area of the compounding area 51 is greatly increased. During the subsequent severing process, the severing position can be located at any position in the compounding area 51, the area available for severing is increased, and the positioning difficulty during the operation of the severing mechanism 3 is reduced.

[0135] As Figure 14As shown, in some embodiments, when performing multiple composites on the material 5 along the transmission direction of the material 5 in step S1021, the breaking position for breaking the material 5 from the composite area 51 of the multi-layer material 5 is located at any one composite position 52 or between any two composite positions 52. As Figure 14 in step S1041.

[0136] When the composite area 51 has one composite position 52, the material 5 can be broken from the composite position 52 to ensure that the multi-layer materials 5 at both ends formed after breaking the material 5 are composite together.

[0137] When the composite area 51 has multiple composite positions 52, the material 5 can be broken along the composite position 52 or between two composite positions 52. When breaking between the composite positions 52, at the breaking position, the multi-layer materials 5 are separated from each other, are soft and easy to break, and can ensure that there is a complete composite area at both ends formed after the material 5 is broken, thereby further preventing the phenomenon of dislocation at any end after breaking.

[0138] In addition, when the method of composite multi-layer material 5 is the method of applying glue, since some glue will adhere to the cutting blade 32 when heated, which will affect the sharpness of the cutting blade 32, so making the cutting position between any two composite positions 52 can avoid the directly contact between the heatable cutting blade 32 and the glue, so as to prevent the glue from adhering to the cutting blade 32 after heating.

[0139] By adopting the above scheme, whether the breaking position is located at any one composite position 52 or between any two composite positions 52, it can ensure that among the two ends formed after breaking the material 5, the materials 5 of each layer are in a composite state, thereby preventing the dislocation problem caused by the delamination of the materials 5 of each layer. As Figure 15 As shown, in some embodiments, when using hot melt to composite the multi-layer material 5, the composite method includes: S1022: Hot melt multiple spaced holes 53 on the material 5, and the multi-layer material 5 is adhesively composite at the edges of the holes 53. The method for breaking the material 5 from the composite area 51 of the multi-layer material 5 includes: S1042: Rotate the first winding needle and / or the second winding needle to break the material 5 from between the multiple spaced holes 53.

[0140] When breaking the material 5, the first winding needle can be rotated only, the second winding needle can be rotated only, or the first winding needle and the second winding needle can be rotated simultaneously.

[0141] By adopting the above solution, holes are formed in the multi-layer material 5 by hot melting, and the multi-layer material 5 is adhesively compounded at the edges of the holes 53 and is not easily separated. On the arrangement line of the holes 53, the material 5 is only connected through the interval areas between the holes 53, so the connection is relatively weak. When the first winding needle and / or the second winding needle rotate, the material 5 located between the first winding needle 12 and the second winding needle 12 is subjected to a large tension and breaks at the relatively weak position, that is, the material 5 breaks between multiple spaced holes 53, realizing the breaking of the material 5 without using a tool, with a simple structure and high operation efficiency.

[0142] As Figure 16 shown, in some embodiments, when hot melting is used to compound the multi-layer material 5, the compounding method further includes: S1023: Hot melting a pre-cut position 54 between multiple spaced holes 53, and the multi-layer material 5 is adhesively compounded at the pre-cut position 54. The method for breaking the material 5 from the compounding area 51 of the multi-layer material 5 further includes: S1043: Rotating the first winding needle and / or the second winding needle to break the material 5 from the pre-cut position 54 between multiple spaced holes 53.

[0143] Among them, S1022 and S1023 can be carried out synchronously or successively.

[0144] By adopting the above solution, the pre-cut position 54 is a weak area of the material 5, and this weak area connects two adjacent holes 53, so that when the first winding needle and / or the second winding needle rotate, the material 5 located between the first winding needle and the second winding needle is more likely to break along the connection line between the pre-cut position 54 and the hole 53 under tension, and the material 5 is not easily deformed during the breaking process.

[0145] As Figure 17 and Figure 18 shown, the embodiment of the present application also provides a core 6, which is wound by a multi-layer material 5. A compounding part 61 is arranged on the multi-layer material 5, and the multi-layer material 5 is laminated and compounded together at the compounding part 61. Along the winding direction, there is a predetermined distance L between the compounding part 61 and the end of the material 5; the end is the innermost end of the material 5 along the winding direction, or the end is the outermost end of the material 5 along the winding direction.

[0146] The compounding part 61 refers to the part where the multi-layer material 5 is compounded and adhered. By setting the compounding part 61, the dislocation between the multi-layer material 5 can be avoided.

[0147] In a core, the number of the compounding parts 61 can be one or more, and each compounding part 61 can have a predetermined distance L from any end of the material 5. For example, as Figure 17As shown, a composite part 61 is provided on a core 6. There is a preset distance L between the composite part 61 and one end of the outermost layer of the material 5 along the winding direction. Then, even if the composite part 61 is not at a preset distance L from one end of the innermost layer of the material 5 along the winding direction, it is still within the protection scope of this application. For another example, as Figure 18 shown, two composite parts 61 are provided on a core 6. The two composite parts 61 can both be at a preset distance L from one end of the outermost layer of the material 5 along the winding direction, or both be at a preset distance L from one end of the innermost layer of the material 5 along the winding direction, or one be at a preset distance L from one end of the innermost layer of the material 5 along the winding direction and the other be at a preset distance L from one end of the innermost layer of the material 5 along the winding direction. The above solutions also fall within the protection scope of this application.

[0148] As Figure 17 and Figure 18 shown, the preset distance L between the composite part 61 and the end of the material 5 refers to the distance from one side of the composite part 61 close to a certain end of the material 5 to this end. The preset distance L is used to define the position of the composite part 61 to prevent the composite part 61 from being too far from the end of the material, causing the layers of the material 5 to swing freely or rebound separately at the end, resulting in delamination between the multiple layers of the material 5.

[0149] The core 6 provided in the embodiment of this application can be wound by any one of the winding devices in the above embodiments using any one of the methods of winding the material in the above embodiments. Therefore, the characteristics and beneficial effects of the core 6 in the embodiment of this application have been described in the above embodiments, and the embodiment of this application will not be elaborated again.

[0150] As Figure 18 shown, in some embodiments, there are multiple composite parts 61, and the multiple composite parts 61 are arranged at intervals. Figure 18 Illustrates the case where there are two composite parts 61 and the two composite parts 61 are arranged at intervals.

[0151] In some embodiments, the multiple layers of the material 5 are composite together at the composite part 61 by means of hot melt composite and / or roll press composite and / or adhesive composite.

[0152] That is to say, the multiple layers of the material 5 can be composite only by one of the ways of hot melt composite or roll press composite or adhesive composite, or can be combined by any two or three of them to form a composite position. For example, roll pressing is carried out while hot melting, or roll pressing is carried out after gluing, or hot pressing is carried out after gluing (the hot melt roller melts while roll pressing).

[0153] It should be noted that in the composite position 52 formed by hot pressing, obvious fusion can be seen between the materials of the multi-layer materials 5 themselves on the cross-section, making it difficult to distinguish the boundaries of the single-layer materials; in the composite position 52 formed by rolling, the adjacent two layers of materials 5 are more closely attached and the material 5 may become thinner; in the composite position formed by adhesive lamination, traces of glue can be seen between the two layers of materials 5 on the cross-section.

[0154] In some embodiments, when the end is one end of the material 5 that is the innermost circle along the winding direction, the predetermined distance L is less than the circumference of the innermost circle of the core 6.

[0155] Since the circumference of the innermost circle of the core 6 is generally greater than 0, the distance between the composite part 61 and the end of the core 6 can be equal to 0, or greater than 0 and less than the circumference of the inner circle. When the distance between the composite part 61 and the end of the core 6 is greater than 0, there is a possibility of misalignment of a section of the material 5 between the end of the core 6 and the composite part 61, and this possibility increases with the increase of the distance. When the core 6 is used as the electrode assembly of the battery cell, since generally only the separator film is laminated and wound in the inner circle of the core 6 and there is no electrode tab, within the range of one week of the innermost circle of the core 6, even if there is a slight misalignment of the material 5, it will not cause a short circuit between the positive electrode tab and the negative electrode tab of the electrode assembly. Therefore, in the embodiments of the present application, when the end is one end of the material 5 that is the innermost circle along the winding direction, setting the predetermined distance L to be less than the circumference of the innermost circle of the core 6 can not only prevent the misalignment of the material 5 caused by the excessive distance between the composite part 61 and the end of the material 5, but also limit the position where the material 5 may be misaligned to the position of the innermost circle of the core 6 where the quality problem of the battery cannot be caused, thereby reducing or even avoiding the battery quality problem caused by the misalignment of the multi-layer materials 5.

[0156] In some embodiments, when the end is one end of the material 5 that is the outermost circle along the winding direction, the predetermined distance L is less than the circumference of the outermost circle of the core 6.

[0157] When the core 6 is used as the electrode assembly of the battery cell, since generally only the separator film is laminated and wound in the outer circle of the core 6 and there is no electrode tab, within the range of one week of the outermost circle of the core 6, even if there is a slight misalignment of the material 5, it will not cause a short circuit between the positive electrode tab and the negative electrode tab of the electrode assembly. Therefore, in the embodiments of the present application, when the end is one end of the material 5 that is the outermost circle along the winding direction, setting the predetermined distance L to be less than the circumference of the outermost circle of the core 6 can not only prevent the misalignment of the material 5 caused by the excessive distance between the composite part 61 and the end of the material 5, but also limit the position where the material 5 may be misaligned to the position of the outermost circle of the core 6 where the quality problem of the battery cannot be caused, thereby reducing or even avoiding the battery quality problem caused by the misalignment of the multi-layer materials 5.

[0158] Such asFigure 17 and Figure 18 As shown in Figure 18 , in some embodiments, the end of the multi-layer material 5 at least partially coincides with or avoids the lamination position 52. Figure 18 Illustrates the case where the end of the material 5 coincides with the lamination position 52, Figure 17 Illustrates the case where the end of the material 5 avoids the lamination position 52.

[0159] In summary, the winding device provided by the embodiments of the present application arranges the lamination mechanism 2 upstream of the winding needle 12, and uses the lamination mechanism 2 to laminate and bond multiple layers of the material 5 together, so that among the two ends formed after the cutting mechanism 3 cuts the material 5 from the lamination area 51, the multiple layers of the material 5 at each end are relatively fixed to each other, thus it is not easy to delaminate during and after the cutting moment, and the situation of misalignment between the layers of the material 5 is avoided.

[0160] Those skilled in the art can understand that although some embodiments herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0161] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; 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 recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A winding device for winding a material, characterized in that, Comprising: A roll-changing mechanism, including a turntable and a plurality of roll needles spaced on the turntable, and the material is wound around one of the roll needles along a preset path; A compounding mechanism, arranged upstream of the roll needle along the preset path, for laminating and compounding multiple layers of the material together at a preset position; A cutting mechanism, arranged between the compounding mechanism and any one of the roll needles along the preset path, for cutting the compounded multiple layers of the material from the compounding area; The compounding mechanism includes: A first hot-melt member and a second hot-melt member arranged opposite and spaced apart, and the material passes between the first hot-melt member and the second hot-melt member; and A driving assembly, connected to the first hot-melt member and / or the second hot-melt member, to drive the first hot-melt member and the second hot-melt member to approach each other, so as to adhesively compound multiple layers of the material by hot pressing; A plurality of convex portions are spaced on the surface of the first hot-melt member and / or the second hot-melt member, and the convex portions are configured to abut against the material to melt out a plurality of spaced holes on the material.

2. The winding device according to claim 1, characterized in that, A pre-cut portion is provided between adjacent convex portions, and the protruding height of the pre-cut portion is lower than that of the convex portion, so as to contact and form a pre-cut position on the material.

3. The winding device according to claim 2, wherein, The cutting mechanism is a central shaft roller arranged at the center of the turntable, and the central shaft roller is used to tension the material between any two roll needles and cut the material compounded together from the pre-cut position.

4. The winding device according to claim 1, characterized in that The compounding mechanism includes a glue-applying member, which is used to spray glue between adjacent two layers of the material to compound the material.

5. The winding device according to any one of claims 1-4, characterized in that The cutting mechanism includes a cutter arranged on the turntable, and the cutter is used to cut the compounded multiple layers of the material from the compounding area.

6. The winding device according to claim 5, characterized in that, The cutter is configured to be a heatable cutter.

7. The winding device according to claim 1, wherein, The winding device further includes a pressing mechanism, which is arranged on one side of the rotation path of the roll needle following the turntable, and is used to press against the material on the roll needle during cutting.

8. A method for winding a material, characterized in that, Comprising: Winding multiple layers of material on the first roll needle of the roll-changing mechanism; Laminating and compounding multiple layers of material at a preset position, including melting out a plurality of spaced holes on the material, and multiple layers of the material are adhesively compounded at the edges of the holes; Rotating the turntable of the roll-changing mechanism to wind the multiple layers of the material on the second roll needle, and the compounding area of the multiple layers of the material is located between the first roll needle and the second roll needle; Cutting the material from the compounding area of the multiple layers of the material, including rotating the first roll needle and / or the second roll needle to pull the material apart from between the plurality of spaced holes.

9. The method for winding a material according to claim 8, characterized in that, Before melting out a plurality of spaced holes on the material and adhesively compounding multiple layers of the material at the edges of the holes, the method for laminating and compounding multiple layers of material at a preset position further includes at least one of roll pressing and glue application.

10. The method for winding a material according to claim 9, characterized in that, When laminating and compounding multiple layers of material at a preset position, multiple compoundings are performed along the transmission direction of the material.

11. The method for winding a material according to claim 10, characterized in that, When cutting the material from the compounding area of the multiple layers of the material, the cutting position is located at any one compounding position or between any two compounding positions.

12. The method of winding a material according to claim 8, characterized in that, When using hot melt to composite the material layer, the composite method further includes: forming a pre-cut position by hot melting between the plurality of spaced holes, and laminating and composite the multi-layer materials at the pre-cut position; The method for cutting off the material from the composite area of the multi-layer materials further includes: rotating the first winding needle and / or the second winding needle to pull off the material from the pre-cut position between the plurality of spaced holes.

13. A core obtained by the winding device according to any one of claims 1-7, characterized in that, It is wound by multi-layer materials, a composite part is provided on the multi-layer materials, the multi-layer materials are laminated and composite together at the composite part, and there is a predetermined distance between the composite part and the end of the material along the winding direction; the end is the innermost end of the material along the winding direction, or the end is the outermost end of the material along the winding direction.

14. The core according to claim 13, characterized in that, There are a plurality of the composite parts, and the plurality of composite parts are spaced apart.

15. The core according to any one of claims 13 or 14, characterized in that, The multi-layer materials are composite together at the composite part by means of hot melt composite and / or roll press composite and / or adhesive composite.

16. The core according to claim 13, wherein, When the end is the innermost end of the material along the winding direction, the predetermined distance is less than the circumference of the innermost circle of the core.

17. The core according to claim 13, characterized in that, When the end is the outermost end of the material along the winding direction, the predetermined distance is less than the circumference of the outermost circle of the core.

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