A battery core winding method and battery core winding machine

Abstract

A cell winding method and a cell winding machine are provided, wherein a composite electrode sheet and a conventional electrode sheet are wound into a cell. Three winding needles are arranged on a winding head. After the cell is wound at a winding station, a second electrode sheet cutter cuts off the second electrode sheet, and the winding needle moves from the winding station to a gluing station. The second electrode sheet feeding pressure roller leaves the first positioning roller of the composite electrode sheet; the second positioning roller of the composite electrode sheet moves, and cooperates with the first positioning roller of the composite electrode sheet to make the composite electrode sheet perpendicular to the winding needle of the winding station; the winding needle of the gluing station compensates for the winding, and the composite electrode sheet cutter cuts off the composite electrode sheet; the winding needle of the winding station clamps the composite electrode sheet and rotates, and a second electrode sheet feeding mechanism sends the second electrode sheet forward, and the second electrode sheet feeding pressure roller approaches the first positioning roller of the composite electrode sheet, presses the second electrode sheet on the composite electrode sheet, and starts winding the cell; when the winding station winds the cell, the gluing station completes the cell tailing and the termination protective glue sticking, and the unloading station completes the cell unloading. The winding process of the present invention is smooth and efficient.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium batteries, and in particular relates to a battery cell winding method and a battery cell winding machine for winding composite pole pieces and conventional pole pieces. Background Art

[0002] Lithium battery cells are mainly made using two processes, one is the winding process, and the other is the lamination process. The winding process is to use a winding machine to wind the pole piece and the diaphragm to make a battery cell. As the requirements for the energy density performance of lithium batteries become higher and higher, in order to improve the energy density, the thickness of the pole piece and the diaphragm is getting thinner and thinner. The thinning of the material thickness brings a series of problems to the winding process. For example, if the base material of the pole piece is too thin, the head of the pole piece will curl after cutting, and it is not easy to insert the winding needle for normal winding; if the diaphragm is too thin, it is easy to deform under the action of tension, and it is easy to shrink after being rolled into a battery cell, causing problems such as wrinkling of the inner pole piece. Therefore, when conventional winding processes are used to produce battery cells using very thin pole pieces and diaphragm materials, the production efficiency and yield rate are often low, and the produced batteries have quality risks.

[0003] In order to solve the problem of too thin material thickness, composite pole pieces have appeared on the market. The composite pole piece is to first compound the pole piece and the diaphragm together, and then wind them. For example, the battery cell winding equipment disclosed in the Chinese utility model patent with patent number 2021201026150 includes a composite discharge device, a positive electrode discharge device and a winding device. The composite discharge device inputs the composite pole piece. The composite pole piece is an integrated structure composite piece formed by the negative pole piece and two diaphragms. The diaphragm is compounded on both sides of the negative pole piece. The positive electrode discharge device outputs the positive pole piece, and the positive pole piece and the composite pole piece are then wound into a battery cell. However, the winding equipment does not take into account the differences in the structure of the composite pole piece and the conventional diaphragm and pole piece, and does not design the process for the composite pole piece. The winding process is not easy to control, and it adopts a single winding needle winding, which is not efficient. Summary of the invention

[0004] The object of the present invention is to provide a battery cell winding method for winding composite pole pieces and conventional pole pieces, which can improve the winding efficiency.

[0005] Another object of the present invention is to provide a battery cell winding machine for winding composite pole sheets and conventional pole sheets.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A battery cell winding method, for winding a composite pole piece and a second pole piece into a battery cell, wherein the composite pole piece comprises a first pole piece and a diaphragm composited on both sides of the first pole piece, the polarity of the second pole piece is opposite to that of the first pole piece, the composite pole piece is provided with a first pole ear, and the second pole piece is provided with a second pole ear;

[0008] The following steps are involved:

[0009] S1. After the composite electrode sheet and the second electrode sheet are respectively unwound by the composite electrode sheet unwinding mechanism and the second electrode sheet unwinding mechanism, the composite electrode sheet is sequentially passed through the composite electrode sheet feeding and correcting assembly and the composite electrode sheet first positioning roller, and sent to the winding head. The winding head is provided with three winding needles. When the winding head rotates, the winding needles thereon can sequentially pass through the winding station, the gluing station and the unloading station, and the composite electrode sheet is sent to the winding needle located at the winding station; the second electrode sheet is sequentially passed through the second electrode sheet feeding mechanism, the second electrode sheet feeding and correcting assembly and the second electrode sheet A feeding pressing roller is sent to the winding needle located at the winding station, and the second pole piece feeding pressing roller is used to press the second pole piece onto the composite pole piece; a first pole piece sensing sensor for sensing the first pole piece and a tape length recording roller for recording the tape length of the composite pole piece are arranged on the tape path of the composite pole piece; a second pole piece cutter is arranged upstream of the second pole piece feeding correction component on the tape path of the second pole piece, and a composite pole piece second positioning roller and a composite pole piece cutter are arranged between the winding station and the glue laminating station;

[0010] S2, the winding needle at the winding station rotates with the composite electrode sheet and the second electrode sheet for winding; when the battery cell is wound at the winding station, the second electrode sheet cutter cuts off the second electrode sheet, and the composite electrode sheet is still connected to the battery cell, and the winding head rotates, and the winding needle with the wound battery cell moves from the winding station to the gluing station, and at the same time, the winding needle with the glued battery cell moves from the gluing station to the unloading station, and the winding needle that has completed unloading moves from the unloading station to the winding station;

[0011] S3, after the winding needle with the wound battery cell moves from the winding station to the glue sticking station, the second pole piece feeding roller retreats, and the tail of the cut second pole piece falls under the second pole piece feeding roller;

[0012] S4, the second positioning roller of the composite electrode sheet moves, close to the composite electrode sheet, and cooperates with the first positioning roller of the composite electrode sheet to make the composite electrode sheet vertically above the winding needle located at the winding station, and the winding needle located at the winding station extends, waiting for the composite electrode sheet to be cut and then clamped;

[0013] S5, the winding needle located at the glue sticking station compensates the corresponding winding angle according to the position of the first pole ear sensed by the first pole ear sensing sensor and the tape length data of the composite pole piece recorded by the tape length recording roller, so that the composite pole piece continues to be wound for a corresponding length, and then the composite pole piece cutter cuts the composite pole piece and separates it from the wound battery cell;

[0014] S6. The winding needle located at the winding station clamps the cut composite electrode sheet and rotates. After the composite electrode sheet is wound to the set process length, the second electrode sheet feeding mechanism feeds the second electrode sheet forward, and the second electrode sheet feeding roller moves forward to press the second electrode sheet onto the composite electrode sheet, and the formal winding of another battery cell begins. In the process of winding the battery cell at the winding station, the gluing station completes the finishing of the battery cell and the affixing of the termination protective glue, and the unloading station completes the unloading of the battery cell. After unloading, the winding needle located at the unloading station retreats to the winding waiting position, waiting to be rotated to the winding station, and the process of steps S2 to S6 is repeated to continue the winding cycle of the next battery cell.

[0015] According to the battery cell winding method as described above, optionally, the composite pole piece feeding correction assembly and the second pole piece feeding correction assembly are respectively used to correct the composite pole piece and the second pole piece before they are fed into the winding needle located at the winding station, the second pole piece feeding correction assembly includes a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes and can approach or move away from each other, the second pole piece correction rollers are driven rollers; a second pole piece support roller is arranged downstream of the first composite pole piece positioning roller, a composite pole piece support roller is arranged between the composite pole piece feeding correction assembly and the first composite pole piece positioning roller, the second pole piece feeding pressure roller is located between the second pole piece feeding correction assembly and the second pole piece support roller, the second pole piece feeding pressure roller and the composite pole piece support roller are arranged opposite to each other, the second pole piece feeding pressure roller and the composite pole piece support roller can approach or move away from each other; the second pole piece feeding pressure roller and the second pole piece support roller move synchronously.

[0016] According to the battery cell winding method as described above, optionally, the composite pole piece feeding correction assembly and the second pole piece feeding correction assembly are respectively used to correct the composite pole piece and the second pole piece before they are fed into the winding needle, the second pole piece feeding correction assembly includes a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes, and can approach or move away from each other, one of the two second pole piece correction rollers is an active rotating roller that can be driven to rotate by a driving unit, and the other is a passive rotating roller and can move relative to the active rotating roller, thereby approaching or leaving the active rotating roller; the second pole piece feeding pressure roller and the composite pole piece first positioning roller are arranged opposite to each other, and can approach or move away from the composite pole piece first positioning roller; the passive rotating shaft and the second pole piece feeding pressure roller move synchronously.

[0017] In the battery cell winding method as described above, optionally, the first pole tab induction sensor is arranged upstream of the composite pole piece feeding correction component, and the tape length recording roller is arranged upstream of the first pole tab induction sensor.

[0018] In the battery cell winding method as described above, optionally, a first pole tab induction sensor is provided upstream of the second pole piece cutter.

[0019] The present invention also provides a battery cell winding machine for winding a composite electrode sheet and a second electrode sheet into a battery cell, the composite electrode sheet comprising a first electrode sheet and a diaphragm composited on the surfaces of both sides of the first electrode sheet, the polarity of the second electrode sheet being opposite to that of the first electrode sheet, the composite electrode sheet being provided with a first electrode ear, and the positive electrode sheet being provided with a second electrode ear; the battery cell winding machine comprises a frame plate, the frame plate being provided with a composite electrode sheet unwinding mechanism, a composite electrode sheet feeding correction component and a composite electrode sheet first positioning roller which are sequentially arranged along the tape running direction of the composite electrode sheet, and a second electrode sheet unwinding mechanism, a second electrode sheet feeding mechanism, a second electrode sheet feeding correction component and a second electrode sheet feeding pressing roller which are sequentially arranged along the tape running direction of the second electrode sheet, and the second electrode sheet feeding pressing roller The roller is used to press the second pole piece onto the composite pole piece; a winding head is arranged below the first positioning roller of the composite pole piece and the second pole piece feeding pressure roller, and three winding needles are arranged on the winding head. When the winding head rotates, the winding needles on it can pass through the winding station, the gluing station and the unloading station in sequence; a movable composite pole piece second positioning roller and a composite pole piece cutter are arranged between the winding station and the gluing station, a second pole piece cutter is arranged upstream of the second pole piece feeding correction component on the tape path of the second pole piece, and a first pole ear sensing sensor for sensing the first pole ear and a tape length recording roller for recording the tape length of the composite pole piece are arranged on the tape path of the composite pole piece.

[0020] As described above, in the battery cell winding machine, optionally, the second pole piece feeding correction component includes a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes, and can approach or move away from each other, and the second pole piece correction rollers are driven rollers; a second pole piece support roller is arranged downstream of the first positioning roller of the composite pole piece, a composite pole piece support roller is arranged between the composite pole piece feeding correction component and the first positioning roller of the composite pole piece, the second pole piece feeding pressure roller is located between the second pole piece feeding correction component and the second pole piece support roller, the second pole piece feeding pressure roller and the composite pole piece support roller are arranged opposite to each other, and the second pole piece feeding pressure roller and the composite pole piece support roller can approach or move away from each other.

[0021] The battery cell winding machine as described above, optionally, the second pole piece feeding correction assembly includes a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes, and can approach or move away from each other, one of the two second pole piece correction rollers is an active rotating roller that can be driven to rotate by a driving unit, and the other is a passive rotating roller and can move relative to the active rotating roller, thereby approaching or moving away from the active rotating roller; the second pole piece feeding pressure roller and the composite pole piece first positioning roller are arranged opposite to each other, and can approach or move away from the composite pole piece first positioning roller.

[0022] The battery cell winding machine as described above may optionally further include a pole piece dust removal mechanism, a composite pole piece tension control mechanism, a second pole piece tension control mechanism, a second pole ear sensing sensor, a tail glue mechanism, a battery cell unloading clamp and a finished product conveyor line; the composite pole piece unwinding mechanism, the pole piece dust removal mechanism, the composite pole piece tension control mechanism, the tape length recording roller, the first pole ear sensing sensor, the composite pole piece feeding correction component, and the composite pole piece first positioning roller are sequentially arranged along the tape running direction of the composite pole piece, and the single positive pole piece unwinding mechanism, the pole piece dust removal mechanism, the positive pole piece tension control mechanism, the tape length recording roller, the second pole piece feeding mechanism, the second pole ear sensing sensor, the second pole piece feeding correction component, and the second pole piece feeding pressure roller are sequentially arranged along the tape running direction of the second pole piece; the tail glue mechanism and the glue sticking station are correspondingly arranged, the battery cell unloading clamp and the unloading station are correspondingly arranged, and the finished product conveyor line is arranged at the discharge end of the unloading station.

[0023] The battery cell winding machine as described above may optionally further include a short-circuit testing mechanism and a CCD appearance detection mechanism arranged along the finished product conveying line.

[0024] It can be seen from the above technical scheme that the winding method and winding machine of the present invention are used for winding composite pole sheets and conventional pole sheets. The composite pole sheet is an integrated structure composed of a pole sheet and a diaphragm located on the surfaces of both sides of the pole sheet, so as to avoid the problem of low production efficiency and yield rate and quality risk of the battery caused by the thickness of the diaphragm or the pole sheet being too thin. During the winding process, the winding method and winding machine of the present invention use the composite pole sheet as the winding carrier and wind the conventional pole sheet to form a battery cell, which can adapt to thinner pole sheets and diaphragms, and the wound battery cell has a higher energy density; and the winding method of the present invention is combined with a winding head with three winding needles, and the conventional winding process is improved according to the structure of the composite pole sheet, and the position of each component is reasonably set to make the battery cell winding process smoother and more efficient. In an optional embodiment, by providing a second pole piece correction roller with an active feeding function, the present invention can also select different second pole piece feeding methods. The second pole piece active feeding method can reduce the tension in the composite pole piece winding process and improve equipment efficiency; the second pole piece passive feeding method can more easily ensure the position accuracy of the positive electrode ear. The second pole piece feeding method can be selected according to different process requirements, which is more practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a schematic diagram of a composite pole piece;

[0027] Figure 2 is a cross-sectional view of a composite pole piece;

[0028] Figure 3 This is a schematic diagram of a winding method according to an embodiment of the present invention when a winding needle of a winding station is winding a battery cell;

[0029] Figure 4 This is a schematic diagram of a method according to an embodiment of the present invention, in which a winding needle of a winding station completes winding and is transferred to a gluing station for final gluing;

[0030] Figure 5 A schematic diagram of feeding positive electrode sheets when a winding needle of a winding station of a method according to an embodiment of the present invention is performing new battery cell winding;

[0031] Figure 6 This is a schematic diagram of a winding needle at a winding station of a winding method according to another embodiment of the present invention performing cell winding;

[0032] Figure 7This is a schematic diagram of a method according to another embodiment of the present invention, in which a winding needle of a winding station completes winding and is transferred to a gluing station for final gluing;

[0033] Figure 8 This is a schematic diagram of feeding positive electrode sheets when a winding needle of a winding station performs new battery cell winding in a method according to another embodiment of the present invention;

[0034] Fig. 9 It is a structural schematic diagram of a battery cell winding machine according to an embodiment of the present invention;

[0035] Fig.10 It is a structural schematic diagram of the battery cell winding machine from another angle according to an embodiment of the present invention.

[0036] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings. DETAILED DESCRIPTION

[0037] The present invention is described in detail below in conjunction with the accompanying drawings. When describing the embodiments of the present invention in detail, for the convenience of explanation, the drawings representing the device structure will not be partially enlarged according to the general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the present invention. It should be noted that the drawings are simplified in form and use non-precise proportions, which are only used to facilitate and clearly assist in explaining the purpose of the embodiments of the present invention. At the same time, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated; the terms "positive", "negative", "bottom", "upper", "lower", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention 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 understood as a limitation to the present invention.

[0038] like Figure 1 and Figure 2 As shown, the composite pole piece includes a pole piece 100 ( Figure 1 The electrode 100 is a composite electrode having a plurality of electrodes (parts shown by the dashed line in the middle) and a diaphragm 200, the diaphragm 200 is respectively covered on the two side surfaces of the electrode 100, the diaphragm 200 and the electrode 100 can be formed into an integrated structure by a pressing process such as hot pressing, and a pole ear 300 is provided on the electrode 100. The composite electrode of this embodiment is a composite structure composed of a negative electrode and a diaphragm, and the diaphragm is composited on the two side surfaces of the negative electrode. The second electrode of the present invention refers to a conventional electrode, which is a electrode with an active material coated on the electrode current collector.

[0039] like Figure 3As shown, the cell winding equipment used in the winding method of this embodiment includes a composite electrode sheet feeding mechanism (not shown), a positive electrode sheet feeding mechanism 1 (a second electrode sheet feeding mechanism), a negative electrode ear induction sensor 2 (a first electrode ear induction sensor), a positive electrode ear induction sensor 3 (a second electrode ear induction sensor), a positive electrode sheet cutter 4 (a second electrode sheet cutter), a composite electrode sheet feeding correction component 5, a positive electrode sheet feeding correction component 6 (a second electrode sheet feeding correction component), a positive electrode sheet feeding roller 7 (a second electrode sheet feeding roller), a composite electrode sheet first positioning roller 8, a positive electrode sheet supporting roller 9 (a second electrode sheet supporting roller), a winding head 10, a composite electrode sheet cutter 11 and a composite electrode sheet second positioning roller 12. The winding head 10 is provided with three winding needles 10-1, and the winding head 10 can rotate so that the winding needles 10-1 located thereon can pass through the winding station A, the gluing station B and the unloading station C in sequence. At the winding station A, the winding needle 10-1 winds the composite electrode sheet 101 and the positive electrode sheet 102 into a battery cell. At the gluing station B, the end protective tape is affixed to the wound battery cell. At the unloading station C, the battery cell is removed from the winding needle 10-1 and placed on the conveyor line for transportation.

[0040] The composite electrode sheet 101 of this embodiment is unwound from the composite electrode sheet unwinding mechanism, passes through the tape length recording roller 13, and then passes through the negative electrode ear induction sensor 2, the composite electrode sheet feeding correction assembly 5, the composite electrode sheet support roller 14, and the composite electrode sheet first positioning roller 8 in sequence, and is sent to the winding needle 10-1 located at the winding station A. The composite electrode sheet first positioning roller 8 is located above the winding needle 10-1 at the winding station A, and the composite electrode sheet second positioning roller 12 is located between the winding station A and the glue sticking station C. The two composite electrode sheet positioning rollers cooperate to enable the composite electrode sheet 101 to be vertically sent to the winding needle 10-1. The composite electrode sheet cutter 11 of this embodiment is located above the composite electrode sheet second positioning roller 12. The composite pole piece feeding correction component 5 is used to correct the composite pole piece 101 before the composite pole piece 101 is fed into the winding needle 10-1. The composite pole piece feeding correction component 5 includes a composite pole piece correction sensor 5-1 and a composite pole piece correction roller 5-2. The composite pole piece correction sensor 5-1 is used to detect whether the position of the composite pole piece 101 is offset. An edge sensor or the like can be used. A pair of composite pole piece correction rollers 5-2 can clamp the composite pole piece 101 and move the composite pole piece 101 to correct its deviation.

[0041] The positive electrode sheet 102 is unwound from the positive electrode sheet unwinding mechanism, conveyed forward by the positive electrode sheet feeding mechanism 1, and sequentially passes through the positive electrode ear sensor 3, the positive electrode sheet feeding correction assembly 6, the positive electrode sheet feeding pressure roller 7 and the positive electrode sheet supporting roller 9, and is delivered to the winding needle 10-1 located at the winding station A. The positive electrode sheet cutter 4 is arranged behind the positive electrode sheet feeding mechanism 1. The positive electrode sheet cutter 4 of this embodiment is arranged between the positive electrode ear sensor 3 and the positive electrode sheet feeding correction assembly 6. The positive electrode sheet feeding correction assembly 6 is used to correct the positive electrode sheet 102 before the positive electrode sheet 102 is fed into the winding needle 10-1, and includes a positive electrode sheet correction sensor 6-1 and a positive electrode sheet correction roller 6-2. The positive electrode sheet correction sensor 6-1 is used to detect whether the position of the positive electrode sheet 102 is offset. A pair of positive electrode sheet correction rollers 6-2 can clamp the positive electrode sheet 102 and move the positive electrode sheet 102 to correct its deviation. The positive electrode sheet feeding pressure roller 7 and the composite electrode sheet supporting roller 14 are arranged opposite to each other, and the positive electrode sheet feeding pressure roller 7 can move relative to the composite electrode sheet supporting roller 14. The positive electrode sheet feeding pressure roller 7 cooperates with the composite electrode sheet supporting roller 14 to press the positive electrode sheet 102 onto the composite electrode sheet 101. In this embodiment, the positive electrode sheet supporting roller 9 is located downstream of the first positioning roller 8 of the composite electrode sheet, and the supporting roller is equivalent to a passing roller, which is used to control the stripping position of the electrode sheet. Optionally, the positive electrode sheet feeding pressure roller 7, the positive electrode sheet supporting roller 9 and the positive electrode sheet deviation correction roller 6-2 arranged on the same side as them move synchronously, and can be moved along Figure 3 The positive electrode sheet correction rollers 6-2 of this embodiment are all driven rollers and cannot actively rotate. Therefore, the feeding method of the positive electrode sheet is passive feeding.

[0042] Combine the following Figure 3 , Figure 4 and Figure 5 The winding method of the battery cell of this embodiment is described as follows:

[0043] S1, such as Figure 3 As shown, after the composite electrode sheet 101 and the positive electrode sheet 102 are respectively unwound by the composite electrode sheet unwinding mechanism and the positive electrode sheet unwinding mechanism, the composite electrode sheet 101 passes through the composite electrode sheet feeding deviation correction component 5, the composite electrode sheet support roller 14 and the composite electrode sheet first positioning roller 8 in sequence, and is sent to the winding needle 10-1 located at the winding station, and the positive electrode sheet 102 passes through the positive electrode sheet feeding mechanism 1, the positive electrode sheet feeding deviation correction component 6, the positive electrode sheet feeding pressure roller 7 and the positive electrode sheet support roller 9 in sequence, and is sent to the winding needle 10-1 located at the winding station A;

[0044] S2, the winding needle 10-1 at the winding station A rotates with the composite electrode sheet 101 and the positive electrode sheet 102 to perform winding; Figure 4As shown, when a battery cell is wound at the winding station A, the positive electrode sheet cutter 4 cuts off the positive electrode sheet 102. At this time, the composite electrode sheet 101 is still connected to the battery cell, and the winding head 10 rotates, moving with the winding needles 10-1 thereon. The winding needle 10-1 with the battery cell that has just been wound moves from the winding station A to the gluing station B. At the same time, the winding needle 10-1 with the battery cell that has been glued moves from the gluing station B to the unloading station C, and the winding needle 10-1 that has completed unloading moves from the unloading station C to the winding station A.

[0045] S3, the positive electrode sheet feeding roller 7, the positive electrode sheet supporting roller 9 and the positive electrode sheet deviation correction roller 6-2 arranged on the same side thereof retreat together and move to the right to leave a feeding space for the positive electrode sheet 102, and at the same time, the cut positive electrode sheet tail falls below the positive electrode sheet supporting roller 9 (positive electrode sheet feeding roller 7);

[0046] S4, the second composite electrode sheet positioning roller 12 moves forward and leans against the composite electrode sheet 101, and cooperates with the first composite electrode sheet positioning roller 8 to make the composite electrode sheet 101 located above it in a vertical state, so that the winding needle 10-1 located at the winding station A can extend and clamp the composite electrode sheet 101. The composite electrode sheet 101 passes through the center of the winding needle 10-1 located at the winding station A. After the composite electrode sheet 101 is cut, it will be clamped by the winding needle 10-1 located at the winding station A;

[0047] S5, the winding needle 10-1 located at the glue sticking station B compensates the corresponding winding angle according to the tab position sensed by the negative tab sensing sensor 2 and the tape length data of the composite pole piece recorded by the tape length recording roller 13, so that the composite pole piece 101 continues to be wound for a corresponding length, and then the composite pole piece cutter 11 cuts the composite pole piece 101;

[0048] S6, such as Figure 5 As shown, after the composite electrode sheet 101 is cut and separated from the wound battery cell, it is clamped by the winding needle 10-1 located at the winding station A, and the winding needle 10-1 of the winding station A rotates to start winding the composite electrode sheet 101. When the composite electrode sheet 101 is wound to the set process length, the positive electrode sheet feeding mechanism 1 sends the head of the positive electrode sheet 102 to the vicinity of the composite electrode sheet roller 14, and the positive electrode sheet feeding roller 7 moves forward and moves to the left, approaching the composite electrode sheet roller 14, and the positive electrode sheet 102 is wound to the set process length. The sheet support roller 9 also moves to the left synchronously, and the positive sheet feeding roller 7 presses the positive sheet 102 onto the composite sheet 101, and the formal winding of another battery cell begins; during the winding process of the battery cell at the winding station A, the glue sticking station B completes the finishing of the battery cell and sticks the termination protective glue, and the unloading station C completes the unloading of the battery cell. The winding needle retreats to the winding waiting position and waits to be rotated to the winding station. The process of steps S2 to S6 is repeated during the production process to continue the winding cycle of the next battery cell. The three stations can act simultaneously, which improves efficiency.

[0049] In step S5, the tape length recording roller 1 records the tape length according to the number of turns it rotates, and the winding needle at the glue sticking station B compensates for the winding angle, that is, the length of the composite electrode sheet that continues to be wound at the glue sticking station B. According to the process requirements, the tape length of the composite electrode sheet is calculated based on the position of the negative electrode ear and the composite electrode sheet. For example, the position of the composite electrode sheet ear sensor 2 is at a, and the position where the electrode ear needs to stop before the composite electrode sheet is cut is at b. The tape length between position a and position b is S, and the distance traveled by the composite electrode sheet when the composite electrode sheet ear sensor 2 senses the electrode ear to the winding stop is S1. The distance traveled by the composite electrode sheet from winding station A to glue sticking station B is S2. Then, the length of the composite electrode sheet that continues to be wound at the glue sticking station is S3=S-S1-S2. The winding needle is generally square or round. After determining S3, it can be converted into the corresponding rotation angle to achieve the compensation winding length S3. S is determined according to the process size and equipment structure. S1 and S2 are detected by the length measuring encoder (tape length recording roller) during the winding process. The above calculation is common knowledge in the field and will not be elaborated here.

[0050] In the above-mentioned embodiment, the positive electrode sheet is fed passively. In other embodiments, the positive electrode sheet can also be fed actively. Figure 6 As shown, in this embodiment, one of the two positive electrode sheet correction rollers 6-2 is a positive electrode sheet feeding correction roller that can be driven to rotate actively by a driving unit, and the other is a positive electrode sheet correction driven roller, that is, the positive electrode sheet correction roller 6-2 can not only correct the position of the electrode sheet, but also realize the active feeding of the positive electrode sheet 101 by actively rotating, and is a positive electrode sheet correction roller with a positive electrode sheet feeding function. Except that the first positioning roller 8 of the composite electrode sheet also has the function of a supporting roller that cooperates with the positive electrode sheet feeding pressure roller 7, the other structures of this embodiment are the same as those of the above-mentioned embodiments. Optionally, in this embodiment, the fixed position positive electrode sheet correction roller 6-2 is set as an active rotating roller that can be driven to rotate by a driving unit such as a motor, and the other positive electrode sheet correction roller 6-2 is a passive rotating roller and can move relative to the positive electrode sheet correction roller 6-2 that can be actively rotated, so as to be close to the positive electrode sheet correction roller 6-2 that can be actively rotated or away from the positive electrode sheet correction roller 6-2 that can be actively rotated.

[0051] Combine the following Figure 6 , Figure 7 and Figure 8 The winding method of the battery cell of this embodiment is described as follows:

[0052] S1, such as Figure 6As shown, after the composite electrode sheet 101 and the positive electrode sheet 102 are respectively unwound by the composite electrode sheet unwinding mechanism and the positive electrode sheet unwinding mechanism, the composite electrode sheet 101 passes through the composite electrode sheet feeding correction component 5 and the composite electrode sheet first positioning roller 8 in sequence, and is sent to the winding needle 10-1 located at the winding station A, and the positive electrode sheet 102 passes through the positive electrode sheet feeding mechanism 1, the positive electrode sheet feeding correction component 6 and the positive electrode sheet feeding pressing roller 7 in sequence, and is sent to the winding needle 10-1 located at the winding station A;

[0053] S2, the winding needle 10-1 at the winding station A rotates with the composite electrode sheet 101 and the positive electrode sheet 102 to perform winding; Figure 7 As shown, when a battery cell is wound at the winding station A, the positive electrode sheet cutter 4 cuts off the positive electrode sheet 102. At this time, the composite electrode sheet 101 is still connected to the battery cell, and the winding head 10 rotates, moving with the winding needles 10-1 located thereon, and the winding needle 10-1 with the battery cell that has just been wound moves from the winding station A to the gluing station B;

[0054] S3, the positive electrode sheet feeding roller 7 and the driven positive electrode sheet deviation correction roller 6-2 arranged on the same side thereof retreat together and move to the right to leave a feeding space for the positive electrode sheet 102, and at the same time, the tail of the cut positive electrode sheet falls under the positive electrode sheet feeding roller 7;

[0055] S4, the second composite electrode sheet positioning roller 12 moves forward, close to the composite electrode sheet 101, and cooperates with the first composite electrode sheet positioning roller 8 to make the composite electrode sheet 101 located above it in a vertical state, so that the winding needle 10-1 located at the winding station A can extend and clamp the composite electrode sheet 101. The composite electrode sheet 101 passes through the center of the winding needle 10-1 located at the winding station A and is clamped by the winding needle 10-1 located at the winding station A;

[0056] S5, the winding needle 10-1 located at the glue sticking station B compensates the corresponding winding angle according to the tab position sensed by the negative tab sensing sensor 2 and the tape length data of the composite pole piece recorded by the tape length recording roller 13, so that the composite pole piece 101 continues to be wound for a corresponding length, and then the composite pole piece cutter 11 cuts the composite pole piece 101;

[0057] S6, such as Figure 8As shown, after the composite electrode sheet 101 is cut and separated from the wound battery cell, it is clamped by the winding needle 10-1 located at the winding station A, and the winding needle 10-1 of the winding station A rotates to start winding the composite electrode sheet 101. When the composite electrode sheet 101 is wound to the set process length, the positive electrode sheet feeding mechanism 1 sends the head of the positive electrode sheet 102 forward to the positive electrode sheet correction roller 6-2, and the actively rotatable positive electrode sheet feeding correction roller rotates to actively feed the positive electrode sheet 102 into the winding needle 10-1 At the same time, the positive electrode sheet feeding roller 7 also moves forward to the left synchronously, pressing the positive electrode sheet 102 onto the composite electrode sheet 101, and starting the formal winding of another battery cell; in the process of winding the battery cell at the winding station A, the gluing station B completes the finishing of the battery cell and the affixing of the termination protective glue, the unloading station C completes the unloading of the battery cell, and then the winding needle 10-1 retreats to the winding waiting position, and while waiting to be rotated to the winding station, the process of steps S2 to S6 is repeated to continue the winding cycle of the next battery cell.

[0058] The winding method of the present invention cooperates with a winding head with three winding needles (stations), improves the conventional winding process according to the structure of the composite pole piece, and makes the battery cell winding process smoother and more efficient by reasonably setting the positions of the negative pole ear sensing sensor, the composite pole sheet cutter, and the composite pole sheet positioning roller. In addition, in an optional embodiment, by setting a positive pole sheet correction roller or a positive pole sheet pressing roller with an active feeding function, the method of the present invention can also select different positive pole feeding methods according to different process requirements. The positive active feeding method can reduce the tension of the composite pole sheet winding process and improve the equipment efficiency; the positive passive feeding method is more likely to ensure the position accuracy of the positive pole ear.

[0059] The present invention also provides a battery cell winding machine for composite electrode sheets, which can use the aforementioned winding method to produce battery cells. The following uses the winding method of actively feeding the positive electrode sheet as an example to illustrate the battery cell winding. Fig. 9 and Fig.10 As shown, the cell winding machine of this embodiment includes a frame plate 20, on which are arranged a positive electrode sheet feeding mechanism 1, a negative electrode ear induction sensor 2, a positive electrode ear induction sensor (not shown), a positive electrode sheet cutter (not shown), a composite electrode sheet feeding correction component 5, a positive electrode sheet feeding correction component 6, a composite electrode sheet first positioning roller 8, a positive electrode sheet feeding pressure roller 7, a winding head 10, a composite electrode sheet cutter (not shown), a composite electrode sheet second positioning roller 12, a tape length recording roller 13, a composite electrode sheet unwinding mechanism 15, a positive electrode sheet unwinding mechanism 16, a composite electrode sheet tension control mechanism 17, a positive electrode sheet tension control mechanism 18, a tail glue mechanism 19, a cell unloading clamp (not shown), a short circuit test mechanism 21, a CCD shape detection mechanism 22, a finished product conveyor line 23, and a pole piece dust removal mechanism 24. The pole piece dust removal mechanism 24 can be a wind knife dust removal mechanism, or a brush dust removal mechanism, or both dust removal mechanisms can be used at the same time.

[0060] The composite electrode sheet unwinding mechanism 15, the electrode sheet dust removal mechanism 24, the composite electrode sheet tension control mechanism 17, the tape length recording roller 13, the negative electrode ear induction sensor 2, the composite electrode sheet feeding correction assembly 5, and the composite electrode sheet first positioning roller 8 are sequentially arranged along the tape running direction of the composite electrode sheet 101. The positive electrode sheet unwinding mechanism 16, the electrode sheet dust removal mechanism 24, the positive electrode sheet tension control mechanism 18, the tape length recording roller 13, the positive electrode sheet feeding mechanism 1, the positive electrode ear induction sensor, the positive electrode sheet feeding correction assembly 6, and the positive electrode sheet feeding pressure roller 7 are sequentially arranged along the tape running direction of the positive electrode sheet 102. The winding head 10 is located below the composite electrode sheet first positioning roller 8 and the positive electrode sheet feeding pressure roller 7. The positive electrode sheet feeding correction component 6 of this embodiment is a feeding correction component with the function of actively feeding the positive electrode sheet. The positive electrode sheet feeding pressure roller 7 and the composite electrode sheet first positioning roller 8 are arranged opposite to each other, and the positive electrode sheet feeding pressure roller 7 can be close to or away from the composite electrode sheet first positioning roller 8. There are three winding needles 10-1 on the winding head 10, and the three winding needles 10-1 can perform winding, gluing and unloading operations of the battery cell at the winding station, gluing station and unloading station respectively. The composite electrode sheet second positioning roller 12 is located between the winding station A and the gluing station C. The composite electrode sheet second positioning roller 12 can move in the horizontal direction, so as to cooperate with the composite electrode sheet first positioning rod 8 to vertically deliver the composite electrode sheet 101 to the winding needle located at the winding station. The composite electrode sheet cutter 11 is located above the composite electrode sheet second positioning roller 12.

[0061] A tail glue mechanism 19 is provided at a position of the frame plate 20 corresponding to the glue sticking station, a battery cell unloading clamp is provided at a position of the frame plate 20 corresponding to the unloading station, a finished product conveyor line 23 is provided at the discharge end of the unloading station, a short circuit testing mechanism 20 and a CCD appearance detection mechanism 22 are sequentially arranged along the sheet conveyor line 23, and are respectively used for short circuit testing and appearance detection of the battery cells. The positive electrode sheet feeding mechanism 1, the negative electrode ear sensing sensor 2, the positive electrode ear sensing sensor, the electrode sheet cutter, the composite electrode sheet feeding correction component 5, the positive electrode sheet feeding correction component 6, the tape length recording roller 13, the composite electrode sheet unwinding mechanism 15, the positive electrode sheet unwinding mechanism 16, the composite electrode sheet tension control mechanism 17, the positive electrode sheet tension control mechanism 18, the tail glue mechanism 19, the battery cell unloading clamp, the short circuit testing mechanism 20, the CCD appearance detection mechanism 22, the finished product conveyor line 23, and the electrode sheet dust removal mechanism 24 of the present invention all adopt the conventional design of the corresponding mechanisms on the conventional winding machine. The present invention does not improve the structure of the above components. The structure of these components can refer to the existing design and will not be repeated here.

[0062] In other embodiments, when the positive electrode sheet feeding correction component 6 does not have the function of actively feeding the positive electrode sheet, a composite electrode sheet roller 14 and a positive electrode sheet roller 9 are respectively arranged behind the composite electrode sheet feeding correction component 5 and the positive electrode sheet feeding correction component 6, and the composite electrode sheet roller 14 and the positive electrode sheet feeding pressure roller 7 are arranged relatively to each other.

[0063] The technical effect of the battery cell winding machine provided in this embodiment is the same or similar to the technical effect of the winding method in the above embodiment, and specific reference is made to the winding method embodiment. In other embodiments, the battery cell winding machine may not use the winding method of the present invention to produce battery cells.

[0064] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery cell winding method, Features: Used to wind a composite pole piece and a second pole piece into a battery core, wherein the composite pole piece includes a first pole piece and a diaphragm composited on both sides of the first pole piece, the polarity of the second pole piece is opposite to that of the first pole piece, the composite pole piece is provided with a first pole ear, and the second pole piece is provided with a second pole ear; The following steps are involved: S1. After the composite electrode sheet and the second electrode sheet are respectively unwound by the composite electrode sheet unwinding mechanism and the second electrode sheet unwinding mechanism, the composite electrode sheet is sequentially passed through the composite electrode sheet feeding and correcting assembly and the composite electrode sheet first positioning roller, and sent to the winding head. The winding head is provided with three winding needles. When the winding head rotates, the winding needles thereon can sequentially pass through the winding station, the gluing station and the unloading station, and the composite electrode sheet is sent to the winding needle located at the winding station; the second electrode sheet is sequentially passed through the second electrode sheet feeding mechanism, the second electrode sheet feeding and correcting assembly and the second electrode sheet A feeding pressing roller is sent to the winding needle located at the winding station, and the second pole piece feeding pressing roller is used to press the second pole piece onto the composite pole piece; a first pole piece sensing sensor for sensing the first pole piece and a tape length recording roller for recording the tape length of the composite pole piece are arranged on the tape path of the composite pole piece; a second pole piece cutter is arranged upstream of the second pole piece feeding correction component on the tape path of the second pole piece, and a composite pole piece second positioning roller and a composite pole piece cutter are arranged between the winding station and the glue laminating station; S2, the winding needle at the winding station rotates with the composite electrode sheet and the second electrode sheet for winding; when the battery cell is wound at the winding station, the second electrode sheet cutter cuts off the second electrode sheet, and the composite electrode sheet is still connected to the battery cell, and the winding head rotates, and the winding needle with the wound battery cell moves from the winding station to the gluing station, and at the same time, the winding needle with the glued battery cell moves from the gluing station to the unloading station, and the winding needle that has completed unloading moves from the unloading station to the winding station; S3, after the winding needle with the wound battery cell moves from the winding station to the glue sticking station, the second pole piece feeding roller retreats, and the tail of the cut second pole piece falls under the second pole piece feeding roller; S4, the second positioning roller of the composite electrode sheet moves, close to the composite electrode sheet, and cooperates with the first positioning roller of the composite electrode sheet to make the composite electrode sheet vertically above the winding needle located at the winding station, and the winding needle located at the winding station extends, waiting for the composite electrode sheet to be cut and then clamped; S5, the winding needle located at the glue sticking station compensates the corresponding winding angle according to the position of the first pole ear sensed by the first pole ear sensing sensor and the tape length data of the composite pole piece recorded by the tape length recording roller, so that the composite pole piece continues to be wound for a corresponding length, and then the composite pole piece cutter cuts the composite pole piece and separates it from the wound battery cell; S6. The winding needle located at the winding station clamps the cut composite electrode sheet and rotates. After the composite electrode sheet is wound to the set process length, the second electrode sheet feeding mechanism feeds the second electrode sheet forward, and the second electrode sheet feeding roller moves forward to press the second electrode sheet onto the composite electrode sheet, and the formal winding of another battery cell begins. In the process of winding the battery cell at the winding station, the gluing station completes the finishing of the battery cell and the affixing of the termination protective glue, and the unloading station completes the unloading of the battery cell. After unloading, the winding needle located at the unloading station retreats to the winding waiting position, waiting to be rotated to the winding station, and the process of steps S2 to S6 is repeated to continue the winding cycle of the next battery cell.

2. The battery cell winding method according to claim 1, Features: The composite pole piece feeding correction assembly and the second pole piece feeding correction assembly are respectively used to correct the composite pole piece and the second pole piece before they are fed into the winding needle located at the winding station, the second pole piece feeding correction assembly comprises a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes and can approach or move away from each other, and the second pole piece correction rollers are driven rollers; A second pole piece supporting roller is arranged downstream of the first positioning roller of the composite pole piece, a composite pole piece supporting roller is arranged between the composite pole piece feeding correction component and the first positioning roller of the composite pole piece, the second pole piece feeding pressure roller is located between the second pole piece feeding correction component and the second pole piece supporting roller, the second pole piece feeding pressure roller and the composite pole piece supporting roller are arranged opposite to each other, the second pole piece feeding pressure roller and the composite pole piece supporting roller can approach or move away from each other; the second pole piece feeding pressure roller and the second pole piece supporting roller move synchronously.

3. The battery core winding method according to claim 1, Features: The composite pole piece feeding correction assembly and the second pole piece feeding correction assembly are respectively used to correct the composite pole piece and the second pole piece before feeding into the winding needle. The second pole piece feeding correction assembly includes a second pole piece correction sensor and a pair of second pole piece correction rollers. The second pole piece correction rollers can rotate around their own axes and can approach or move away from each other. One of the two second pole piece correction rollers is an active rotating roller that can be driven to rotate by a driving unit, and the other is a passive rotating roller that can move relative to the active rotating roller to approach or leave the active rotating roller. The second pole piece feeding roller and the first positioning roller of the composite pole piece are arranged opposite to each other and can be close to or away from the first positioning roller of the composite pole piece; the passive rotating roller and the second pole piece feeding roller move synchronously.

4. The battery core winding method according to claim 1, Features: The first pole tab induction sensor is arranged upstream of the composite pole piece feeding correction component, and the tape length recording roller is arranged upstream of the first pole tab induction sensor.

5. The battery cell winding method according to claim 1, Features: A first pole tab induction sensor is arranged upstream of the second pole piece cutter.

6. A cell winding machine using the cell winding method according to claim 1, used to wind a composite pole piece and a second pole piece into a cell, wherein the composite pole piece comprises a first pole piece and a diaphragm composited on both sides of the first pole piece, the polarity of the second pole piece is opposite to that of the first pole piece, the composite pole piece is provided with a first pole ear, and the second pole piece is provided with a second pole ear; Features: The machine comprises a frame plate, on which a composite pole piece unwinding mechanism, a composite pole piece feeding deviation correction component and a composite pole piece first positioning roller are sequentially arranged along the tape running direction of the composite pole piece, and a second pole piece unwinding mechanism, a second pole piece feeding mechanism, a second pole piece feeding deviation correction component and a second pole piece feeding pressing roller are sequentially arranged along the tape running direction of the second pole piece, and the second pole piece feeding pressing roller is used to press the second pole piece onto the composite pole piece; A winding head is arranged below the first positioning roller of the composite electrode sheet and the second electrode sheet feeding pressure roller, and three winding needles are arranged on the winding head. When the winding head rotates, the winding needles on it can pass through the winding station, the gluing station and the unloading station in sequence; A movable composite electrode sheet second positioning roller and a composite electrode sheet cutter are arranged between the winding station and the glue laminating station, a second electrode sheet cutter is arranged on the tape path of the second electrode sheet and upstream of the second electrode sheet feeding correction component, and a first electrode sheet sensing sensor for sensing the first electrode sheet and a tape length recording roller for recording the tape length of the composite electrode sheet are arranged on the tape path of the composite electrode sheet.

7. The battery cell winding machine according to claim 6, Features: The second pole piece feeding correction assembly comprises a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes and can approach or move away from each other, and the second pole piece correction rollers are driven rollers; A second pole piece supporting roller is arranged downstream of the first positioning roller of the composite pole piece, a composite pole piece supporting roller is arranged between the composite pole piece feeding correction component and the first positioning roller of the composite pole piece, the second pole piece feeding pressure roller is located between the second pole piece feeding correction component and the second pole piece supporting roller, the second pole piece feeding pressure roller and the composite pole piece supporting roller are arranged opposite to each other, and the second pole piece feeding pressure roller and the composite pole piece supporting roller can be close to or away from each other.

8. The battery cell winding machine according to claim 6, Features: The second pole piece feeding correction assembly comprises a second pole piece correction sensor and a pair of second pole piece correction rollers, the second pole piece correction rollers can rotate around their own axes and can approach or move away from each other, one of the two second pole piece correction rollers is an active rotating roller that can be driven to rotate by a driving unit, and the other is a passive rotating roller that can move relative to the active rotating roller to approach or move away from the active rotating roller; The second pole piece feeding pressure roller and the first positioning roller of the composite pole piece are arranged opposite to each other and can be close to or far away from the first positioning roller of the composite pole piece.

9. The battery cell winding machine according to claim 6, Features: It also includes a pole piece dust removal mechanism, a composite pole piece tension control mechanism, a second pole piece tension control mechanism, a second pole ear induction sensor, a tail glue mechanism, a battery cell unloading clamp and a finished product conveyor line; The composite electrode unwinding mechanism, the electrode dust removal mechanism, the composite electrode tension control mechanism, the tape length recording roller, the first pole ear induction sensor, the composite electrode feeding correction component, and the composite electrode first positioning roller are sequentially arranged along the tape running direction of the composite electrode, and the second electrode unwinding mechanism, the electrode dust removal mechanism, the second electrode tension control mechanism, the tape length recording roller, the second electrode feeding mechanism, the second pole ear induction sensor, the second pole feeding correction component, and the second pole roller are sequentially arranged along the tape running direction of the second pole; The tail glue sticking mechanism and the glue sticking station are arranged correspondingly, the battery cell unloading clamp and the unloading station are arranged correspondingly, and the finished product conveying line is arranged at the unloading end of the unloading station.

10. The battery cell winding machine according to claim 9, Features: It also includes a short-circuit testing mechanism and a CCD appearance detection mechanism arranged along the finished product conveying line.

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