Battery jelly-roll, winding device and method thereof, and battery

Abstract

Embodiments of the present application provide a battery roll core, a winding device and method thereof, and a battery, and relate to the field of battery manufacturing. The winding device comprises a winding needle assembly, a plurality of thickening sheet groups, and a thickening sheet control mechanism. The winding needle assembly comprises a winding needle and a winding needle driving mechanism connected to the winding needle and used for controlling rotation of the winding needle. The plurality of thickening sheet groups are sequentially arranged in multiple layers from a direction close to a shaft line of the winding needle to a direction far from the shaft line. Each thickening sheet group comprises a plurality of thickening sheets. In a working state, the winding needle works, and the thickening sheets move along a direction parallel to a length direction of the winding needle, and move to a position where a projection of the thickening sheet and the working part of the winding needle on a plane parallel to the shaft line of the winding needle coincides. The winding method uses the winding device to wind the roll core. The battery roll core is obtained by using the winding method. The battery is obtained by using the battery roll core. The winding device and the winding method can eliminate stress generated in the winding process.

Description

Technical Field

[0001] This invention relates to the field of battery manufacturing, and more specifically, to a battery core, a winding device and method thereof, and a battery. Background Technology

[0002] High-capacity lithium-ion batteries mostly employ a winding process because it offers advantages such as high production efficiency, low assembly difficulty, and high safety at the end of their lifespan. However, the presence of winding stress in the core can significantly affect the core's condition and subsequent performance. To control or reduce this stress, the industry has made numerous attempts, such as using circular winding needles, variable tension winding, coated separators, and pattern rollers, but the results have not been entirely satisfactory.

[0003] Poor winding stress, such as S-bends in the core, wrinkles in the electrode sheet, wrinkles in the separator, and subsequent core deformation, can lead to problems such as black spots on the electrode sheet, lithium plating, excessively thick core, low capacity, and cycle degradation.

[0004] Therefore, how to solve the adverse effects of winding stress, eliminate stress generation at its source, and thus improve the condition of the winding core is a problem that needs to be solved.

[0005] Therefore, this application is hereby submitted. Summary of the Invention

[0006] The object of the present invention includes, for example, providing a battery core and its winding device, method and battery, aimed at improving at least one of the problems mentioned in the background art.

[0007] The embodiments of the present invention can be implemented as follows:

[0008] In a first aspect, the present invention provides a core winding apparatus, comprising:

[0009] Needle coiling assembly, multiple sets of thickening sheet groups, and thickening sheet control mechanism;

[0010] The needle winding assembly includes a needle winding and a needle winding drive mechanism connected to the needle winding and used to control the rotation of the needle winding;

[0011] Multiple thickening sheet groups are distributed in multiple layers from the direction closest to to the axis of the winding needle. Each thickening sheet group includes multiple thickening sheets. When the core winding device is working, each thickening sheet has two states: working state and non-working state.

[0012] When not in operation, the working parts of the needle coil do not overlap on a plane parallel to the axis of the needle coil.

[0013] In the working state, the needle coiling is working, and the thickening plate moves in a direction parallel to the length direction of the needle coiling until the projections of the working parts of the thickening plate and the needle coiling on a plane parallel to the axis of the needle coiling coincide.

[0014] The thickening sheet control mechanism is configured in conjunction with each thickening sheet to control the movement of the thickening sheet until its projection on the winding needle coincides with the working part of the winding needle.

[0015] In an optional embodiment, the core winding device further includes a controller, which is electrically connected to the needle drive mechanism and the thickening sheet control mechanism.

[0016] The controller is configured to perform an action program for the built-in thickening sheet. According to the action program, it issues instructions to the thickening sheet control mechanism to move all the thickening sheets in a group of thickening sheets.

[0017] The action sequence is that the needle winding drive mechanism controls the needle winding to rotate to a specific number of revolutions before performing the action.

[0018] In an optional implementation, the thickening sheet control mechanism includes a housing and a drive assembly;

[0019] The shell has multiple thickening plate channels inside and multiple thickening plate inlets and outlets on the outer wall of the shell. The multiple thickening plate channels and multiple thickening plate inlets and outlets are connected one-to-one, and each thickening plate is set in one thickening plate channel.

[0020] The drive assembly is either a pneumatic drive assembly or a hydraulic drive assembly. The drive assembly is used to drive the thickening sheet to extend out of or retract into the thickening sheet channel. The drive assembly is connected in communication with the controller, which is configured to control the drive assembly to drive the thickening sheet to perform extension and retraction actions.

[0021] In an optional implementation, the drive assembly includes an air supply mechanism, multiple vent valves, and multiple elastic elements;

[0022] The end of the housing away from the inlet and outlet of the thickening sheet is provided with multiple air inlets, and each air inlet is connected to a channel of the thickening sheet.

[0023] Multiple elastic elements are located one-to-one within the thickening sheet channel. One end of the elastic element is connected to the end of the housing away from the thickening sheet inlet and outlet, and the other end is connected to one end of the thickening sheet.

[0024] Each air inlet is equipped with a corresponding air vent valve. The air supply mechanism is connected to each air vent valve. The air vent valve and the air supply mechanism are connected to the controller. The controller is configured to control the opening or closing of the air vent valve and the opening or closing of the air supply mechanism.

[0025] Optionally, a connecting block is provided at one end of the thickening sheet that connects to the elastic element. The connecting block is directly connected to the elastic element, and the edge of the connecting block is in contact with the inner wall of the thickening sheet channel.

[0026] In an optional implementation, the elastic element is a spring or an elastic cord.

[0027] In an optional embodiment, the housing is annular, and the needle winding drive mechanism is disposed within the annulus of the housing, integrated with the housing as a single unit.

[0028] Secondly, the present invention provides a method for winding a core, comprising:

[0029] The electrode sheet and the diaphragm are wound into a core using a core winding device as described in any of the foregoing embodiments.

[0030] In optional implementations, the specific components include:

[0031] After the diaphragm is pre-wound by the winding needle, the positive and negative electrode sheets are inserted.

[0032] When the specified number of turns is reached, the thickening sheet control mechanism controls the corresponding thickening sheet to extend to the working part around the winding needle, so that the thickening sheet is attached to the surface of the core.

[0033] The winding needle continues to rotate, and the thickening sheets are wound into the core. When all the thickening sheets are embedded in the core, the winding is complete.

[0034] The control mechanism for the thickening sheet moves the thickening sheet to a non-working state.

[0035] Separate the winding needle and the winding core;

[0036] Optionally, the needle drive mechanism can also control the extension and retraction of the core, and before the needle clamps the diaphragm, it also includes: controlling the needle drive mechanism to extend the core;

[0037] The method to separate the winding needle and the winding core is to control the winding needle drive mechanism to retract the winding core.

[0038] Thirdly, the present invention provides a battery core, which is obtained by winding using the core winding method described in the foregoing embodiments.

[0039] Fourthly, the present invention provides a battery made from a battery core as described in the foregoing embodiments.

[0040] The beneficial effects of the embodiments of the present invention include, for example:

[0041] The core winding device and method, due to the inclusion of thickening sheets and a thickening sheet control mechanism, allows the corresponding layer's thickening sheet to be moved to the outer periphery of the winding needle's working area and brought into contact with the core during the core winding process, reaching a specified number of turns. This allows the thickening sheet to be wound into the core. Every few turns, a set of thickening sheets is moved and wound into the core. After winding is complete, the thickening sheets and winding needle are removed. This eliminates winding stress at its source, improves the core's condition, and solves the deformation problem caused by core stress, thereby improving core performance. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the structure of the winding needle and the thickening sheet of the core winding device provided in an embodiment of the present invention when they are extended;

[0044] Figure 2 for Figure 1 Right view of the middle shell;

[0045] Figure 3 This is a schematic diagram of the structure when the thickening sheet is located in the thickening sheet inlet / outlet channel;

[0046] Icons: 100-Core winding device; 111-Winding needle; 120-Thickening sheet; 121-Connecting block; 130-Controller; 140-Housing; 141-Thickening sheet channel; 142-Thickening sheet inlet and outlet; 151-Air supply mechanism; 152-Vent valve; 153-Elastic element. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0049] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0050] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0051] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0052] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0053] Please refer to Figures 1-3 This embodiment provides a core winding device 100, including:

[0054] Needle winding assembly, multiple sets of thickening sheet groups, and thickening sheet 120 control mechanism;

[0055] The needle winding assembly includes a needle winding 111 and a needle winding drive mechanism connected to the needle winding 111 and used to control the rotation of the needle winding 111;

[0056] Multiple sets of thickening sheets are distributed in multiple layers from the direction closest to to the axis of the winding needle 111. Each set of thickening sheets includes multiple thickening sheets 120. When the core winding device 100 is working, each thickening sheet 120 has two states: working state and non-working state.

[0057] When not in operation, the winding needle 111 is working, and the projections of the working parts of the thickening sheet 120 and the winding needle 111 on a plane parallel to the axis of the winding needle 111 do not coincide.

[0058] When in operation, the winding needle 111 works, and the thickening plate 120 moves along a direction parallel to the length direction of the winding needle 111 until the projections of the working parts of the thickening plate 120 and the winding needle 111 on a plane parallel to the axis of the winding needle 111 coincide.

[0059] The thickening sheet 120 control mechanism is configured in conjunction with each thickening sheet 120 to control the movement of the thickening sheet 120 until its projection on the winding needle 111 coincides with the working part of the winding needle 111.

[0060] The working part of the winding needle 111 mentioned in this application refers to the part used to clamp and wind the diaphragm and electrode sheet during winding. In addition, the winding needle assembly mentioned in this application is prior art. The winding needle assembly only needs to realize the function of winding the core of the winding needle 111. Some core assemblies can also realize the extension and retraction of the winding needle 111. The winding needle 111 with extension and retraction function is retracted into the winding needle drive mechanism before working. During working, it extends out of the winding needle drive mechanism and retracts back into the winding needle drive mechanism after winding is completed. Its specific structure is the same as that of the existing winding needle assembly. Therefore, it will not be described in detail in this application, and the accompanying drawings are only schematic and do not disclose its specific details.

[0061] The core winding device 100 provided by this invention, due to the provision of the thickening sheet 120 and the thickening sheet 120 control mechanism, during the core winding process, when a specified number of turns are reached, the corresponding layer of the thickening sheet 120 is moved to the outer periphery of the working part of the winding needle 111 to fit against the core, so that the thickening sheet 120 is wound into the core; every few turns, a group of thickening sheets 120 is moved and wound into the core; after winding is completed, the thickening sheet 120 and the winding needle 111 are removed. This eliminates winding stress at its source, improves the core condition, solves the deformation problem caused by core stress, and thus achieves the effect of improving core performance.

[0062] Specifically, the number of thickening sheets 120 in each thickening sheet group of the present invention is 2, 3, 4, 5, 6, 7 or 8, etc. In the illustrated scheme, the number of thickening sheets 120 in each thickening sheet group is 4.

[0063] Preferably, the core winding device 100 further includes a controller 130, which is electrically connected to the winding needle drive mechanism and the thickening sheet 120 control mechanism.

[0064] The controller 130 is configured to operate the built-in thickening sheet 120. According to the operation program, the controller 130 issues instructions to the control mechanism of the thickening sheet 120 to move all the thickening sheets 120 in a group of thickening sheets.

[0065] The action program is that the winding needle drive mechanism controls the winding needle 111 to rotate to a specific number of revolutions before performing the action.

[0066] The setting of the controller 130 being electrically connected to the winding needle drive mechanism and the thickening sheet 120 control mechanism enables intelligent core winding and improves winding efficiency.

[0067] The built-in program of the controller 130 is configured, for example, to drive the thickening sheet 120 to extend when the electrode is wound in the order of 1, 3, 5...n, n+2, n+4..., so that the thickening sheet 120 is embedded in the core; or to drive the thickening sheet 120 to extend when the electrode is wound in the order of 2, 4, 6...n, n+2, n+4..., so that the thickening sheet 120 is embedded in the core.

[0068] Preferably, the control mechanism for the thickened sheet 120 includes a housing 140 and a drive assembly;

[0069] The housing 140 has multiple thickening sheet channels 141 inside and multiple thickening sheet inlets and outlets 142 on the outer wall of the housing 140. The multiple thickening sheet channels 141 and the multiple thickening sheet inlets and outlets 142 are connected one-to-one. Each thickening sheet 120 is disposed in one thickening sheet channel 141.

[0070] The drive assembly is a pneumatic drive assembly or a hydraulic drive assembly. The drive assembly is used to drive the thickening sheet 120 to extend out of the thickening sheet channel 141 or retract into the thickening sheet channel 141. The drive assembly is communicatively connected to the controller 130, which is configured to control the drive assembly to drive the thickening sheet 120 to perform extension and retraction actions.

[0071] The drive assembly can be a pneumatic drive assembly or a hydraulic drive assembly, and its specific structure can refer to existing pneumatic cylinders and hydraulic cylinders, while the thickened plate 120 corresponds to the piston rod. Pneumatic cylinders and hydraulic cylinders are existing technologies and will not be described in detail here.

[0072] In some embodiments of this application, specifically, the structure of the drive assembly includes, for example, an air supply mechanism 151, a plurality of vent valves 152, and a plurality of elastic elements 153;

[0073] The end of the housing 140 away from the thickening sheet inlet / outlet 142 is provided with multiple air inlets, and each air inlet is connected to a multiple thickening sheet channel 141.

[0074] Multiple elastic elements 153 are located one-to-one in the thickening sheet channel 141. One end of the elastic element 153 is connected to the end of the housing 140 away from the thickening sheet inlet / outlet 142, and the other end is connected to one end of the thickening sheet 120.

[0075] Each air inlet is provided with a corresponding air vent valve 152. The air supply mechanism 151 is connected to each air vent valve 152. The air vent valve 152 and the air supply mechanism 151 are communicatively connected to the controller 130. The controller 130 is configured to control the opening or closing of the air vent valve 152 and the opening or closing of the air supply mechanism 151.

[0076] When the core is wound to the number of turns set by the built-in program in the controller 130, the controller 130 controls the corresponding vent valve 152 to open, allowing air to enter the thickening sheet channel 141 and push the thickening sheet 120 out of the thickening sheet channel 141, so that the thickening sheet 120 is embedded in the core. When the core is wound, the air supply mechanism 151 stops working, the air in the thickening sheet channel 141 is discharged, and the thickening sheet 120 retracts into the thickening sheet channel 141 under the pulling force of the elastic element 153.

[0077] Furthermore, a connecting block 121 is provided at one end of the thickening sheet 120 that is connected to the elastic member 153. The connecting block 121 is directly connected to the elastic member 153, and the edge of the connecting block 121 is in contact with the inner wall of the thickening sheet channel 141.

[0078] The connection block 121 is designed to be in contact with the inner wall of the channel to prevent air leakage and facilitate the passage of gas into the thickening plate channel 141 to push the thickening plate 120.

[0079] Specifically, the thickening sheet 120 is made of stainless steel or aluminum alloy and coated with polytetrafluoroethylene. In addition, the thickening sheet 120 can be selected in various thicknesses, and different thickening sheets 120 can be installed and removed according to the specific size and model of the battery to be manufactured.

[0080] Furthermore, the elastic element 153 can be the most common spring or elastic cord.

[0081] Furthermore, in order to improve the overall integrity of the device and make it easy to use, the housing 140 is annular, and the needle winding drive mechanism is disposed inside the annulus of the housing 140 and integrated with the housing 140.

[0082] The core winding method provided in this embodiment of the invention includes:

[0083] The core winding device 100 provided in this embodiment of the invention is used to wind the electrode sheet and the diaphragm to form a core.

[0084] Furthermore, the winding needle assembly used is a winding needle 111 with a telescopic function, and the winding method specifically includes:

[0085] The winding needle drive mechanism is controlled to extend the winding core, and the winding needle 111 clamps the diaphragm and pre-winds it one and a half times before the positive and negative electrode sheets are inserted into the wafer.

[0086] When the specified number of turns is reached, the thickening sheet 120 control mechanism controls the corresponding group of thickening sheets 120 to extend to the working part surrounding the winding needle 111, so that the thickening sheet 120 is attached to the surface of the core.

[0087] The winding needle 111 continues to rotate, and the thickening sheet 120 is wound into the core. The winding is completed when all the thickening sheets 120 are embedded in the core.

[0088] The control mechanism of the thickening sheet 120 moves the thickening sheet 120 to a non-working state;

[0089] Control the winding needle drive mechanism to retract the winding core.

[0090] The winding method for the core provided in this embodiment of the invention uses the winding device provided in this embodiment of the invention to wind the core. During the winding process, the thickening sheet 120 is embedded in the core at a specified number of winding turns, which can effectively eliminate winding stress, improve the core condition, solve the deformation problem caused by core stress, and thus achieve the effect of improving core performance.

[0091] This invention also provides a battery core, which is obtained by winding using the core winding method provided in this invention.

[0092] This invention also provides a battery made from the winding core provided in this invention.

[0093] Experimental Example

[0094] Experimental group: The positive electrode was lithium iron phosphate, the negative electrode was graphite, and the separator was PE-based film. The positive electrode, negative electrode, and separator were wound into a core. During the winding process, four 0.5mm thick thickening sheets were embedded at the 2nd, 4th, 6th, 8th...16th, 18th, and 20th turns respectively. This core was then used to make a 280Ah battery.

[0095] Control group: The same positive electrode, negative electrode, and separator as the experimental group were wound using existing winding methods to obtain a core, which was then used to manufacture a 280Ah battery. The "existing winding method" mentioned here refers to the method used in the experimental group, the only difference being that no thickening sheet was embedded during the winding process.

[0096] Data on the cores of the experimental and control groups, as well as disassembly data after the cells were fully charged and charged and discharged for 10 weeks, were collected and the experimental results were recorded in Table 1.

[0097] Table 1. Electrochemical performance test results of the experimental group and the control group.

[0098]

[0099]

[0100] As shown in Table 1, the S-bend of the core prepared by this method is significantly reduced, the thickness of the core after cold pressing is greatly reduced, and the thickness of the core after hot pressing is also significantly lower than that of the control group. The cores of the control group and the experimental group were assembled, formed, and capacity tested to form battery cells. After being fully charged and disassembled or charged and discharged at 0.5C / 0.5C for 10 cycles and then disassembled, the thickness of the cores in the experimental group was also significantly lower than that in the control group. After unfolding the cores, it was found that the negative electrode sheet of the inner circle of the core in the control group had obvious wrinkles, and the wrinkles became more severe towards the inner circle. In contrast, the negative electrode sheet of the core in the experimental group had almost no wrinkles. This shows that the winding method provided by this invention can solve the problem of poor stress during the winding process.

[0101] In summary, the winding device 100 and winding method provided by this invention, due to the provision of the thickening sheet 120 and the thickening sheet 120 control mechanism, during the winding process, when a specified number of turns are reached, the thickening sheet 120 of the corresponding layer is moved to the outer periphery of the working part of the winding needle 111 to fit against the core, so that the thickening sheet 120 is wound into the core; every few turns, a set of thickening sheets 120 is moved to be wound into the core, and after winding is completed, the thickening sheet 120 and the winding needle 111 are removed. This eliminates winding stress at its source, improves the core condition, solves the deformation problem caused by core stress, and thus achieves the effect of improving core performance.

[0102] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A core winding device, characterized in that, include: Needle coiling assembly, multiple sets of thickening sheet groups, and thickening sheet control mechanism; The needle winding assembly includes a needle winding and a needle winding drive mechanism connected to the needle winding and used to control the rotation of the needle winding; The multiple sets of thickening sheets are distributed in multiple layers from the direction closest to to the axis of the winding needle. Each set of thickening sheets includes multiple thickening sheets. When the core winding device is working, each thickening sheet has two states: working state and non-working state. When not in operation, the winding needle is working, and the projections of the thickening sheet and the working part of the winding needle on a plane parallel to the axis of the winding needle do not coincide. In the working state, the coiling needle is working, and the thickening plate moves along a direction parallel to the length direction of the coiling needle until the projections of the working parts of the thickening plate and the coiling needle on a plane parallel to the axis of the coiling needle coincide. The thickening sheet control mechanism is configured in conjunction with each thickening sheet to control the movement of the thickening sheet until its projection on the winding needle coincides with the working part of the winding needle. The core winding device also includes a controller, which is electrically connected to the winding needle drive mechanism and the thickening sheet control mechanism. The controller is configured to have a built-in action program for the thickening sheet, and according to the action program, it issues instructions to the thickening sheet control mechanism to move all the thickening sheets in a group of thickening sheets. The thickening sheet control mechanism includes a housing and a drive assembly; The housing has multiple thickening sheet channels inside and multiple thickening sheet inlets and outlets on the outer wall of the housing. The multiple thickening sheet channels are connected to the multiple thickening sheet inlets and outlets one by one, and each thickening sheet is disposed in one of the thickening sheet channels. The drive assembly is a pneumatic drive assembly or a hydraulic drive assembly, which is used to drive the thickening sheet to extend out of the thickening sheet channel or retract into the thickening sheet channel; the drive assembly is communicatively connected to the controller, which is configured to control the drive assembly to drive the thickening sheet to perform extension and retraction actions.

2. The core winding device according to claim 1, characterized in that, The action procedure is that the winding needle drive mechanism controls the winding needle to rotate to a specific number of revolutions before performing the action.

3. The core winding device according to claim 1, characterized in that, The drive assembly includes an air supply mechanism, multiple air valves, and multiple elastic elements; The housing is provided with a plurality of air inlets at the end away from the thickening sheet inlet and outlet, and the plurality of air inlets are connected to the plurality of thickening sheet channels one by one. The plurality of elastic elements are located one-to-one within the thickening sheet channel. One end of each elastic element is connected to the end of the housing away from the thickening sheet inlet and outlet, and the other end is connected to one end of the thickening sheet. Each air inlet is provided with a corresponding air vent valve. The air supply mechanism is connected to each air vent valve. The air vent valve and the air supply mechanism are communicatively connected to the controller. The controller is configured to control the opening or closing of the air vent valve and the opening or closing of the air supply mechanism.

4. The core winding device according to claim 3, characterized in that, A connecting block is provided at one end of the thickening sheet that is connected to the elastic element. The connecting block is directly connected to the elastic element, and the edge of the connecting block is in contact with the inner wall of the thickening sheet channel.

5. The core winding device according to claim 3, characterized in that, The elastic element is a spring or an elastic rope.

6. The core winding device according to claim 4, characterized in that, The housing is circular, and the needle winding drive mechanism is disposed inside the circular ring of the housing and integrated with the housing as one unit.

7. A method for winding a core, characterized in that, include: The electrode sheet and the diaphragm are wound into a core using the core winding device as described in any one of claims 1 to 6.

8. The core winding method according to claim 7, characterized in that, Specifically, it includes: After the winding needle clamps the diaphragm and pre-winds it one and a half times, the positive electrode sheet and the negative electrode sheet are inserted into the wafer; When the winding reaches the specified number of turns, the thickening sheet control mechanism controls the corresponding group of thickening sheets to extend to the working part surrounding the winding needle, so that the thickening sheet adheres to the surface of the winding core; The winding needle continues to rotate, and the thickening sheet is wound into the winding core. The winding is completed when all the thickening sheets are embedded in the winding core. Control the thickening sheet control mechanism to move the thickening sheet to the non-working state; Separate the winding needle and the winding core.

9. The core winding method according to claim 8, characterized in that, The needle winding drive mechanism can also control the extension and retraction of the needle, and before the needle clamps the diaphragm, it further includes: controlling the needle winding drive mechanism to extend the needle; The method for separating the winding needle and the winding core is to control the winding needle drive mechanism to retract the winding needle.

10. A battery core, characterized in that, It is obtained by winding the core using the core winding method described in any one of claims 7 to 9.

11. A battery, characterized in that, It is made from the battery core as described in claim 10.

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