Battery cell winding method capable of adjusting dislocation of tabs

Abstract

The invention relates to a battery cell winding method capable of adjusting dislocation of tabs. Relates to the technical field of cell winding. The method specifically comprises the following steps: step S1, unwinding a cathode pole piece, an anode pole piece and a diaphragm to a winding needle; s2, winding the cathode pole piece, the anode pole piece and the diaphragm by using a winding needle; s3, obtaining the dislocation quantity of the tabs, and comparing the obtained dislocation quantity of the tabs with the standard dislocation quantity; s4, the tension of diaphragm unwinding is adjusted; s5, turning over the battery core roll; and S6, discharging the battery cell roll. According to the adjustment of the dislocation of the tabs of the battery cell roll, the tension of unwinding the diaphragm is adjusted through the tension adjusting mechanism, so that the diaphragm applies acting force to the turned battery cell roll, and tabs of multiple layers of cathode plates and anode plates in the battery cell roll generate relative displacement, so that the adjustment of the dislocation of the tabs of the wound battery cell is simple and efficient, and the production efficiency is improved; and the adjustment precision of the dislocation quantity of the tabs is improved, the winding yield of the battery cell roll is improved, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of battery core winding, and in particular to a battery core winding capable of adjusting the misalignment of a tab Circumvention method. Background Art

[0002] At present, in the field of secondary battery production, the winding process is the mainstream process for square cells, which has the characteristics of high cell output, good safety performance, and high energy density. In the winding process, the commonly used method is to die-cut the pole piece first, and then wind and bond the cathode pole piece, anode pole piece, and two layers of isolation film on the winding needle in the order of "isolation film-cathode pole piece-isolation film-anode pole piece".

[0003] Since the thickness of the same rolled pole piece fluctuates during the winding process, the fluctuation of the pole piece thickness will cause the pole ear of the wound battery cell to be misaligned, thereby affecting the assembly and welding current capacity of the subsequent process of the wound battery cell. Therefore, during the winding process, the pole ear misalignment of the wound battery cell needs to be adjusted. In the prior art, the operator usually adjusts the pole ear misalignment by frequently adjusting the circumference of the winding needle by tearing off Teflon, etc. This method is time-consuming and labor-intensive, and cannot guarantee the adjustment accuracy of the pole ear misalignment, thereby reducing production efficiency and winding yield, and increasing production costs. Summary of the invention

[0004] The object of the present invention is to provide a battery cell winding method with adjustable tab misalignment to address the deficiencies of the above-mentioned prior art, so that the adjustment of the tab misalignment of the wound battery cell is simple and efficient, thereby improving production efficiency, and improving the adjustment accuracy of the tab misalignment, thereby improving the winding yield and reducing production costs.

[0005] The present invention provides a battery cell winding method capable of adjusting the misalignment of the tabs, comprising the following steps: Step S1: unwinding the cathode electrode sheet, the anode electrode sheet and the separator onto the winding needle; Step S2: the cathode electrode sheet, the anode electrode sheet and the separator are wound to form a battery cell roll, and the separator separates the cathode electrode sheet from the anode electrode sheet; Step S3: obtaining the misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll, and comparing the obtained misalignment of the tabs with the standard misalignment; Step S4: according to the comparison result of the tab misalignment amount and the standard misalignment amount, the tension adjustment mechanism adjusts the tension of the diaphragm unwinding; Step S5: the turning mechanism operates to drive the winding needle to turn over, and the winding needle drives the battery cell winding to turn over; Step S6: unloading the battery cell roll on the winding needle through the unloading needle clamping mechanism.

[0006] Further, obtaining the misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll includes: The misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll is measured by a CCD visual detection unit to obtain a numerical value of the misalignment of the tabs.

[0007] Further, the obtained tab misalignment amount is compared with a standard misalignment amount, including: Determine whether the tab misalignment exceeds the standard misalignment. If the tab misalignment exceeds the standard misalignment, execute step S4; if the tab misalignment does not exceed the standard misalignment, skip step S4 and execute step S5.

[0008] Further, the standard misalignment is D1, the tab misalignment is D2, the difference between the tab misalignment and the standard misalignment is ΔD, ΔD= D2- D1, and step S4 includes: Step S4.1: deriving a relationship between the ΔD and the tension F of the diaphragm unwinding by data fitting; Step S4.2: recording the current value of △D, and calculating the value of the tension F of the diaphragm unwinding according to the current value of △D through a relational expression; Step S4.3: adjusting the tension F of the membrane unwinding to the calculated value through the tension adjustment mechanism.

[0009] Further, step S1 includes: Step S1.1: Unwind the first layer of diaphragm onto the winding needle through the first diaphragm unwinding mechanism Step S1.2: unwinding the cathode electrode sheet onto the winding needle through the cathode electrode sheet unwinding mechanism; Step S1.3: unwinding the second layer of diaphragm onto the winding needle through the second diaphragm unwinding mechanism; Step S1.4: unwinding the anode electrode sheet onto the winding needle through the anode electrode sheet unwinding mechanism.

[0010] Further, the first membrane unwinding mechanism and the second membrane unwinding mechanism both include a membrane unwinding shaft and a membrane roller, the tension adjustment mechanism is disposed between the membrane roller and the winding needle, and step S1.2 includes: The membrane unwinding shaft outputs the membrane, and the membrane is wound on the winding needle after passing through the membrane roller and the tension adjustment mechanism in sequence.

[0011] Further, the battery cell roll includes an initial battery cell roll, and step S2 includes: The winding needle rotates around its own axis to roll together the cathode electrode sheet, the anode electrode sheet and the separator of a certain length to form the initial battery cell roll.

[0012] Further, the battery cell roll also includes a formed battery cell roll, the turning mechanism includes a turntable, the winding needle is arranged at a position deviating from the axis on the turntable, and step S5 includes: Step S5.1: the turntable rotates around its own axis, driving the winding needle to flip around the axis of the turntable, and the winding needle drives the initial battery cell to flip around the axis of the turntable; Step S5.2: cutting the separator on the initial battery cell roll by a cutting mechanism to form the formed battery cell roll.

[0013] Furthermore, the turntable is provided with a working position and a material unloading position, the winding needle comprises a first winding needle and a second winding needle, initially, the first winding needle is located at the working position, and the second winding needle is located at the material unloading position, and step S5.1 comprises: The turntable rotates around its own axis, driving the first winding needle and the second winding needle to flip synchronously around the axis of the turntable, so that the first winding needle flips from the working position to the unloading position, and the second winding needle flips from the unloading position to the working position, and the first winding needle drives the initial battery cell roll to flip from the working position to the unloading position.

[0014] Further, the blanking clamping needle mechanism includes an inner clamping needle and an outer clamping roller, and step S6 includes: Step S6.1: the inner clamping needle extends into the battery cell roll and stretches the battery cell roll to separate the battery cell roll from the winding needle, and the winding needle is pulled out of the battery cell roll. In the process of the inner clamping needle stretching the battery cell roll, the residual misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll is eliminated; Step S6.2: The outer clamping roller clamps the battery cell roll at the outer side, and pulls the inner clamping needle away from the battery cell roll.

[0015] The present invention provides a battery cell winding method with adjustable tab misalignment, which has the following beneficial effects: (1) In the present battery cell winding method, the adjustment of the misalignment of the battery cell tabs is achieved by adjusting the tension of the separator unwinding through a tension adjustment mechanism, so that the separator applies a certain force to the flipped battery cell roll, thereby causing the tabs of the cathode and anode tabs in the battery cell roll to move in the same direction and in a consistent manner, thereby making the adjustment of the misalignment of the tabs of the wound battery cell simple and efficient, thereby improving production efficiency, and improving the adjustment accuracy of the tab misalignment, thereby improving the winding yield of the battery cell roll and reducing production costs; (2) In the present battery cell winding method, due to the influence of the thickness of the cathode electrode sheet, the anode electrode sheet and the separator, the tabs of the cathode electrode sheet and the anode electrode sheet in the wound battery cell roll have the same direction and the same misalignment amount. Therefore, the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll are photographed by the CCD visual detection unit, and the photographed information is analyzed, so as to obtain the accurate value of the tab misalignment amount in the battery cell roll; (3) The battery cell winding method firstly fits the relationship between △D and the tension F of the separator unwinding through data fitting; then, according to the calculated current △D value, the tension F value of the separator unwinding can be calculated through the relationship; finally, according to the calculated tension F value of the separator unwinding, the tension adjustment mechanism adjusts the tension F of the separator unwinding to a specified value, so that after the separator adjusts the misalignment of the tab of the battery cell roll, the misalignment of the tab is within the range of the standard misalignment, thereby improving the adjustment accuracy of the tab misalignment, improving the winding yield of the battery cell roll, and reducing the production cost; (4) In the present battery cell winding method, a cathode electrode sheet of a required length is placed on the cathode electrode sheet unwinding mechanism, an anode electrode sheet of a required length is placed on the anode electrode sheet unwinding mechanism, and the length of the separator placed on the first separator unwinding mechanism and the second separator unwinding mechanism exceeds the required separator length, thereby eliminating the cathode electrode sheet and the anode electrode sheet cutting process in the battery cell roll production process, thereby making the battery cell roll production simpler and more efficient, thereby improving production efficiency; (5) The turntable of the battery cell winding method is provided with a working position and a material unloading position, and the winding needle includes a first winding needle and a second winding needle. Initially, the first winding needle is located at the working position and the second winding needle is located at the material unloading position. Therefore, the first winding needle and the second winding needle are driven by the turntable to interchange positions, so that the first winding needle and the second winding needle can alternately wind the battery cell roll, thereby further making the production of the battery cell roll simpler and more efficient, and improving production efficiency; (6) When the inner clamping needle of the present battery cell winding method applies force to the formed battery cell roll from the inside, the tabs of the cathode electrode sheet and the anode electrode sheet in the formed battery cell roll will be displaced to a certain extent, thereby eliminating the remaining misalignment of the tabs in the formed battery cell roll, making the formed battery cell roll meet the standards of a qualified battery cell roll, further improving the winding yield of the battery cell roll, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In the accompanying drawings, like reference numerals are used to represent like elements.

[0017] Figure 1 It is a schematic structural diagram of a separator adjusting the tab misalignment amount of a cell winding in a cell winding method capable of adjusting tab misalignment according to an embodiment of the present invention; Figure 2A plan view of a battery cell roll before the diaphragm is adjusted in a battery cell winding method with adjustable tab misalignment according to an embodiment of the present invention; Figure 3 A plan view of a battery cell roll after the diaphragm is adjusted in a battery cell winding method with adjustable tab misalignment according to an embodiment of the present invention; Figure 4 A top view of a battery cell roll after adjustment of the blanking clamp needles in a battery cell winding method with adjustable tab misalignment according to an embodiment of the present invention.

[0018] In the figure: 1. First winding needle; 2. Second winding needle; 3. Turntable; 4. Tension adjustment mechanism; 5. Diaphragm unwinding shaft; 6. Diaphragm roller; 7. Diaphragm; 8. Initial battery cell roll; 9. Formed battery cell roll; 10. Tab. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0020] A battery cell winding method with adjustable tab misalignment according to an embodiment of the present invention comprises the following steps: Step S1: unwinding the cathode electrode sheet, the anode electrode sheet and the diaphragm 7 onto the winding needle; Step S2: Winding the cathode electrode sheet, the anode electrode sheet and the separator 7 to form a battery cell roll, wherein the separator 7 separates the cathode electrode sheet from the anode electrode sheet; Step S3: obtaining the misalignment of the tabs of the cathode and anode tabs in the battery cell roll, and comparing the obtained misalignment of the tabs with the standard misalignment; Step S4: according to the comparison result of the tab misalignment amount and the standard misalignment amount, the tension adjustment mechanism 4 adjusts the unwinding tension of the diaphragm 7; Step S5: the turning mechanism operates to drive the winding needle to turn over, and the winding needle drives the battery cell winding to turn over; Step S6: unloading the battery cell roll on the winding needle through the unloading needle clamping mechanism.

[0021] In this patent, when winding the battery cell, the cathode electrode sheet, the anode electrode sheet and the two layers of the separator 7 are first unwound onto the winding needle, and then the cathode electrode sheet, the anode electrode sheet and the two layers of the separator 7 are wound in the order of "separator 7-cathode electrode sheet-separator 7-anode electrode sheet" through the winding needle to form a battery cell roll, so that the separator 7 isolates the cathode electrode sheet from the anode electrode sheet to prevent the cathode electrode sheet from contacting the anode electrode sheet and causing a short circuit.

[0022] Then, the misalignment of the tabs of the cathode and anode plates in the battery cell roll is obtained, and the obtained misalignment of the tabs is compared with the standard misalignment; based on the comparison result, the tension of the unwinding of the diaphragm 7 is adjusted by the tension adjustment mechanism 4; after the tension adjustment is completed, the flipping mechanism is operated to drive the winding needle to flip, and the winding needle drives the battery cell roll to flip synchronously.

[0023] Affected by the thickness of the cathode electrode sheet, the anode electrode sheet and the separator 7, the tabs 10 of the cathode electrode sheet and the anode electrode sheet in the wound battery cell roll have the same direction and the same amount of misalignment. During the flipping of the battery cell roll, the separator 7 is not cut, so that the separator 7 exerts a force on the battery cell roll, so that the tabs 10 of the multiple layers of cathode electrode sheets and anode electrode sheets in the battery cell roll have the same direction and the same relative displacement, and the direction of the displacement is opposite to the direction of the misalignment of the tabs 10 of the battery cell roll, thereby adjusting the misalignment of the tabs 10 of the battery cell roll.

[0024] Finally, the battery cell roll on the winding needle is unloaded through the unloading clamping needle mechanism, thereby completing the production of the battery cell roll. In this patent, the adjustment of the misalignment of the battery cell roll pole ear 10 is automatically completed during the production process of the battery cell roll, making the adjustment of the misalignment of the wound battery cell pole ear 10 simple and efficient, thereby improving production efficiency.

[0025] The misalignment of the tabs 10 of the battery cell roll is adjusted by accurately adjusting the tension of the unwinding diaphragm 7 through the tension adjustment mechanism 4, so that the diaphragm 7 applies a specified force to the flipped battery cell roll, thereby accurately controlling the relative displacement of the tabs 10 of the multi-layer cathode and anode sheets in the battery cell roll, thereby improving the adjustment accuracy of the tab misalignment, improving the winding yield of the battery cell roll, and reducing production costs.

[0026] Specifically, in this embodiment, the amount of misalignment of the tabs of the cathode pole piece and the anode pole piece in the battery cell roll is obtained, including: measuring the amount of misalignment of the tabs of the cathode pole piece and the anode pole piece in the battery cell roll by a CCD visual detection unit to obtain a numerical value of the misalignment of the tabs.

[0027] Due to the influence of the thickness of the cathode electrode sheet, the anode electrode sheet and the separator 7, the tabs 10 of the cathode electrode sheet and the anode electrode sheet in the wound battery cell roll have the same direction and consistent misalignment. Therefore, the tabs 10 of the cathode electrode sheet and the anode electrode sheet in the battery cell roll are photographed by the CCD visual inspection unit, and the photographed information is analyzed to obtain the accurate value of the misalignment of the tabs in the battery cell roll.

[0028] In this patent, since the lengths of the cathode electrode sheet, anode electrode sheet and separator 7 in the battery cell roll are different for different products, the misalignment of the tab 10 in the wound battery cell roll will also be different. After obtaining the precise value of the misalignment of the tab in the battery cell roll, the obtained misalignment of the tab is first compared with the standard misalignment.

[0029] If the misalignment of the pole lugs of the current battery cell roll is within the range of the standard misalignment, the misalignment of the pole lugs of the battery cell roll can be adjusted in a small range in the subsequent winding process to obtain a qualified battery cell roll. Therefore, there is no need to adjust the misalignment of the pole lugs 10 through the diaphragm 7. That is, in the steps of the battery cell winding method, step S4 can be skipped and step S5 can be performed directly. The turning mechanism is operated to drive the winding needle to turn over, so that the winding needle drives the battery cell roll to turn over. Finally, the battery cell roll on the winding needle is unloaded at the specified position to complete the production of the battery cell roll.

[0030] If the misalignment of the tabs of the current battery cell roll exceeds the standard misalignment range, the subsequent winding process will make a small adjustment to the misalignment of the tabs of the battery cell roll, and a qualified battery cell roll cannot be obtained. At this time, step S4 needs to be performed first, so that the tension adjustment mechanism 4 adjusts the tension of the separator 7 unwinding according to the misalignment of the tabs of the current battery cell roll.

[0031] Then proceed to step S5, and drive the winding needle to turn over by operating the flipping mechanism, so that the winding needle drives the battery cell roll to turn over. During the flipping process of the battery cell roll, the separator 7 applies a force to the battery cell roll, so that the tabs 10 of the multi-layer cathode and anode plates in the battery cell roll are relatively displaced, thereby adjusting the tab misalignment of the battery cell roll so that the tab misalignment of the tab 10 is within the standard misalignment range. Then, the tab misalignment of the battery cell roll is adjusted in a small range through the subsequent winding process to obtain a qualified battery cell roll, thereby improving production efficiency and reducing production costs.

[0032] Specifically, in this embodiment, the standard misalignment is D1, the tab misalignment is D2, the difference between the tab misalignment and the standard misalignment is △D, △D= D2- D1, and step S4 includes: Step S4.1: fitting the data to find the relationship between ΔD and the tension F of the membrane 7 during unwinding; Step S4.2: Record the current value of △D, and calculate the value of the tension F of the unwinding of the diaphragm 7 through a relational expression according to the current value of △D; Step S4.3: The tension F of the unwinding membrane 7 is adjusted to the calculated value by the tension adjustment mechanism 4.

[0033] In the previous embodiment, it is mentioned that: when the misalignment of the tabs of a battery cell roll exceeds the range of a standard misalignment, the tension of the unwinding of the diaphragm 7 is adjusted by the tension adjustment mechanism 4, so that the diaphragm 7 exerts a force on the battery cell roll during the flipping of the battery cell roll, causing the tabs 10 of the multiple layers of cathode and anode plates in the battery cell roll to produce relative displacement, thereby adjusting the misalignment of the tabs of the battery cell roll so that the misalignment of the tabs 10 is within the range of a standard misalignment.

[0034] Therefore, the separator 7 exerts a force on the battery cell roll to adjust the tab misalignment of the battery cell roll, which is to adjust the difference △D between the tab misalignment D2 of the battery cell roll and the standard misalignment D1. Since the standard misalignment D1 is a fixed value, after the value of the tab misalignment D2 is obtained by the CCD visual detection unit, the difference △D between the tab misalignment D2 and the standard misalignment D1 can be calculated.

[0035] In this patent, the relationship between △D and the tension F of the unwinding of the diaphragm 7 is firstly fitted through data; then, according to the calculated value of the current △D, the value of the tension F of the unwinding of the diaphragm 7 can be calculated through the relationship; finally, according to the calculated value of the tension F of the unwinding of the diaphragm 7, the tension adjustment mechanism 4 adjusts the tension F of the unwinding of the diaphragm 7 to a specified value, so that after the diaphragm 7 adjusts the misalignment of the tab of the battery cell roll, the misalignment of the tab is within the range of the standard misalignment, thereby improving the adjustment accuracy of the misalignment of the tab, improving the winding yield of the battery cell roll, and reducing the production cost.

[0036] In this embodiment, step S1 includes: Step S1.1: Unwind the first layer of diaphragm onto the winding needle through the first diaphragm unwinding mechanism Step S1.2: unwinding the cathode electrode sheet onto the winding needle through the cathode electrode sheet unwinding mechanism; Step S1.3: unwinding the second layer of diaphragm onto the winding needle through the second diaphragm unwinding mechanism; Step S1.4: unwinding the anode electrode sheet onto the winding needle through the anode electrode sheet unwinding mechanism.

[0037] Specifically, in actual implementation, when the cathode electrode sheet, anode electrode sheet and diaphragm 7 are unwound, the first layer of diaphragm is first unwound to the winding needle through the first diaphragm unwinding mechanism, that is, the first layer of diaphragm is located on the first layer, and then the cathode electrode sheet is unwound to the winding needle through the cathode electrode sheet unwinding mechanism, that is, the cathode electrode sheet is located on the second layer, and then the second layer of diaphragm is unwound to the winding needle through the second diaphragm unwinding mechanism, that is, the second layer of diaphragm is located on the third layer.

[0038] Finally, the anode electrode sheet is unwound to the winding needle through the anode electrode sheet unwinding mechanism, that is, the anode electrode sheet is located on the fourth layer, so that the cathode electrode sheet, the anode electrode sheet and the two layers of the diaphragm 7 are unwound to the winding needle in the order of "diaphragm 7-cathode electrode sheet-diaphragm 7-anode electrode sheet", so that the diaphragm 7 isolates the cathode electrode sheet from the anode electrode sheet to prevent the cathode electrode sheet from contacting the anode electrode sheet and causing a short circuit.

[0039] In this patent, according to the required lengths of cathode plates, anode plates and diaphragm 7 in the battery cell rolls of different products, cathode plates of corresponding lengths are placed on the cathode plate unwinding mechanism, and anode plates of corresponding lengths are placed on the anode plate unwinding mechanism, while the length of the diaphragm 7 placed on the first diaphragm unwinding mechanism and the second diaphragm unwinding mechanism exceeds the required length of the diaphragm 7.

[0040] Therefore, when the winding needle is winding the cathode electrode sheet, the anode electrode sheet and the diaphragm 7, all the cathode electrode sheets on the cathode electrode sheet unwinding mechanism and all the anode electrode sheets on the anode electrode sheet unwinding mechanism are wound into the battery cell roll. After the diaphragm 7 of the specified length on the first diaphragm unwinding mechanism and the second diaphragm unwinding mechanism is wound into the battery cell roll, the diaphragm 7 remains uncut, so that after the tension adjustment mechanism 4 adjusts the tension of the unwinding diaphragm 7, during the flipping process of the battery cell roll, the diaphragm 7 exerts a force on the battery cell roll, causing the tabs 10 of the multiple layers of cathode electrode sheets and anode electrode sheets in the battery cell roll to produce relative displacement, thereby adjusting the misalignment of the tabs of the battery cell roll.

[0041] After the battery cell roll is flipped to the specified position, the diaphragm 7 is cut off by the cutting mechanism, and finally the battery cell roll is cut to complete the production of the battery cell roll. In this way, the cutting process of the cathode and anode plates is omitted during the production of the battery cell roll, thereby making the production of the battery cell roll simpler and more efficient, thereby improving production efficiency.

[0042] In this embodiment, the first membrane unwinding mechanism and the second membrane unwinding mechanism both include a membrane unwinding shaft 5 and a membrane roller 6, and the tension adjustment mechanism 4 is disposed between the membrane roller 6 and the winding needle. Step S1.2 includes: The membrane unwinding shaft 5 outputs the membrane 7, and the membrane 7 is wound on the winding needle after passing through the membrane roller 6 and the tension adjustment mechanism 4 in sequence.

[0043] In this patent, the first membrane unwinding mechanism and the second membrane unwinding mechanism both include a membrane unwinding shaft 5 and a membrane roller 6. A membrane roll of a certain length is placed on the membrane unwinding shaft 5, and the end of the membrane roll on the membrane unwinding shaft 5 is passed out. The tension adjustment mechanism 4 is two respectively arranged between the first membrane unwinding mechanism and the winding needle and between the second membrane unwinding mechanism and the winding needle.

[0044] The end of the diaphragm roll transmitted from the diaphragm unwinding shaft 5 is wound on the winding needle after passing through the diaphragm roller 6 and the tension adjustment mechanism 4 in sequence, so that the diaphragm 7 transmitted from the diaphragm unwinding shaft 5 is wound through the operation of the winding needle. During the winding process of the diaphragm 7, the tension adjustment mechanism 4 adjusts the tension of the diaphragm 7, which can ensure the tension of the diaphragm 7 during normal winding on the one hand, and on the other hand, when the battery cell roll is turned over, the diaphragm 7 applies a force to the battery cell roll, so that the tabs 10 of the multi-layer cathode and anode plates in the battery cell roll are relatively displaced, so as to adjust the misalignment of the tabs of the battery cell roll.

[0045] In this embodiment, the battery cell roll includes an initial battery cell roll 8, and step S2 includes: The winding needle rotates around its own axis to roll together a certain length of cathode electrode sheet, anode electrode sheet and separator 7 to form an initial battery cell roll 8.

[0046] In this patent, a cathode electrode sheet of a certain length is placed on the cathode electrode sheet unwinding mechanism, an anode electrode sheet of a corresponding length is placed on the anode electrode sheet unwinding mechanism, and the length of the diaphragm 7 placed on the first diaphragm unwinding mechanism and the second diaphragm unwinding mechanism exceeds the required diaphragm 7 length.

[0047] When the first diaphragm unwinding mechanism unwinds the first layer of diaphragm 7 onto the winding needle, the cathode electrode sheet unwinding mechanism unwinds the cathode electrode sheet onto the winding needle, the second diaphragm unwinding mechanism unwinds the second layer of diaphragm 7 onto the winding needle, and the anode electrode sheet unwinding mechanism unwinds the anode electrode sheet onto the winding needle, the winding needle rotates around its own axis to wind up the cathode electrode sheet, the anode electrode sheet and the two layers of diaphragm 7 until the cathode electrode sheet on the cathode electrode sheet unwinding mechanism and the anode electrode sheet on the anode electrode sheet unwinding mechanism are unwound. At this time, the diaphragm 7 wound onto the winding needle remains uncut, thereby forming an initial battery cell roll 8 on the winding needle.

[0048] Further, in this embodiment, the battery cell roll also includes a formed battery cell roll 9, the turning mechanism includes a turntable 3, and the winding needle is arranged at a position deviating from the axis of the turntable 3, and step S5 includes: Step S5.1: the turntable 3 rotates around its own axis, driving the winding needle to flip around the axis of the turntable 3, and the winding needle drives the initial battery cell roll 8 to flip around the axis of the turntable 3; Step S5.2: The separator 7 on the initial battery cell roll 8 is cut by a cutting mechanism to form a formed battery cell roll 9.

[0049] As mentioned in the previous embodiment, the winding needle rotates around its own axis to wind the cathode electrode sheet, the anode electrode sheet and the two layers of the separator 7 until the cathode electrode sheet on the cathode electrode sheet unwinding mechanism and the anode electrode sheet on the anode electrode sheet unwinding mechanism are unwound, and the separator 7 wound on the winding needle remains uncut, and at this time an initial battery cell roll 8 is formed on the winding needle.

[0050] In this patent, the turning mechanism includes a turntable 3, and the winding needle is arranged at a position deviating from the axis of the turntable 3. After the tension adjustment mechanism 4 adjusts the tension F of the unwinding of the diaphragm 7 to a specified value, the turntable 3 is first rotated around its own axis to drive the winding needle to turn around the axis of the turntable 3, thereby driving the initial battery cell roll 8 formed on the winding needle to turn synchronously.

[0051] During this process, since the diaphragm 7 wound onto the winding needle remains uncut, the diaphragm 7 will exert a force on the initial battery cell roll 8, causing the tabs 10 of the multi-layer cathode and anode plates in the initial battery cell roll 8 to be relatively displaced, thereby adjusting the misalignment of the tabs of the initial battery cell roll 8.

[0052] When the initial battery cell roll 8 is flipped to the specified position and the tab misalignment is adjusted, the diaphragm 7 is cut at this position by the cutting mechanism, so that the initial battery cell on the winding needle forms a molded battery cell roll 9, and finally the molded battery cell roll 9 on the winding needle is unloaded to complete the production of the battery cell roll.

[0053] In this embodiment, a working position and a material unloading position are provided on the turntable 3, and the winding needle includes a first winding needle 1 and a second winding needle 2. Initially, the first winding needle 1 is located at the working position, and the second winding needle 2 is located at the material unloading position. Step S5.1 includes: The turntable 3 rotates around its own axis, driving the first winding needle 1 and the second winding needle 2 to flip synchronously around the axis of the turntable 3, so that the first winding needle 1 flips from the working position to the unloading position, and the second winding needle 2 flips from the unloading position to the working position, and the first winding needle 1 drives the initial battery cell roll 8 to flip from the working position to the unloading position.

[0054] In this patent, a working position and a material discharge position are provided at a position deviating from the axis on the turntable 3, and the working position and the material discharge position are symmetrically arranged with the axis of the turntable 3 as the center. The winding needle includes a first winding needle 1 and a second winding needle 2. Initially, the first winding needle 1 is arranged at the working position, and the second winding needle 2 is arranged at the material discharge position.

[0055] When making a battery cell roll, the cathode electrode sheet, the anode electrode sheet and the two layers of the separator 7 are unwound onto the first winding needle 1, and the first winding needle 1 is rotated around its own axis to realize the winding of the cathode electrode sheet, the anode electrode sheet and the separator 7, thereby forming an initial battery cell roll 8 on the first winding needle 1.

[0056] In actual implementation, preferably, the working position is set just above the material unloading position. When the turntable 3 rotates around its own axis, it rotates 180° counterclockwise, driving the first winding needle 1 and the second winding needle 2 to synchronously flip 180° around the axis of the turntable 3, so that the first winding needle 1 flips from the working position to the material unloading position, and the second winding needle 2 flips from the material unloading position to the working position.

[0057] When the first winding needle 1 flips, it drives the initial battery cell roll 8 to flip synchronously around the axis of the turntable 3. During this process, the diaphragm 7 applies a force to the initial battery cell roll 8 on the first winding needle 1, causing the tabs 10 of the multi-layer cathode and anode plates in the initial battery cell roll 8 to produce relative displacement, thereby adjusting the misalignment of the tabs.

[0058] Until the first winding needle 1 flips from the unloading position to the working position, driving the initial battery cell roll 8 to flip from the working position to the unloading position, the adjustment of the tab misalignment is completed, so that it is convenient for the cutting mechanism to cut the diaphragm 7 at the unloading position, so that the initial battery cell roll 8 on the first winding needle 1 forms a shaped battery cell roll 9; finally, the shaped battery cell roll 9 on the first winding needle 1 is unloaded at the unloading position through the unloading needle clamping mechanism, thereby completing the production of the battery cell roll.

[0059] The second winding needle 2 flipped to the working position can be used to make the next battery cell roll, that is, the cathode electrode sheet, anode electrode sheet and two layers of separator 7 for making the next battery cell roll are first unwound onto the second winding needle 2, and the second winding needle 2 is rotated around its own axis to realize the winding of the cathode electrode sheet, anode electrode sheet and separator 7, thereby forming the next initial battery cell roll 8 on the second winding needle 2.

[0060] The turntable 3 then continues to rotate 180° counterclockwise around its own axis, driving the first winding needle 1 and the second winding needle 2 to synchronously flip 180° around the axis of the turntable 3, so that the second winding needle 2 flips from the working position to the unloading position, and the first winding needle 1 flips from the unloading position to the working position.

[0061] At this time, the second winding needle 2 drives the next initial battery cell roll 8 to flip from the working position to the unloading position. During this process, the diaphragm 7 exerts a force on the initial battery cell roll 8 on the second winding needle 2, causing the tabs 10 of the multi-layer cathode and anode plates in the initial battery cell roll 8 to produce relative displacement, thereby adjusting the misalignment of the tabs.

[0062] When the next initial battery cell roll 8 reaches the unloading position, the adjustment of the misalignment of its tabs is completed, and then the diaphragm 7 is cut off at the unloading position by the cutting mechanism, so that the initial battery cell roll 8 on the second winding needle 2 is formed into a shaped battery cell roll 9; finally, the unloading needle clamping mechanism is used at the unloading position to unload the shaped battery cell roll 9 on the second winding needle 2, thereby completing the production of the next battery cell roll, thereby making the production of the battery cell roll simpler and more efficient, and improving production efficiency.

[0063] In this embodiment, the blanking clamping needle mechanism includes an inner clamping needle and an outer clamping roller, and step S6 includes: Step S6.1: the inner clamping needle extends into the battery cell roll and stretches the battery cell roll to separate the battery cell roll from the winding needle, and the winding needle is pulled out of the battery cell roll. In the process of the inner clamping needle stretching the battery cell roll, the residual misalignment of the tabs of the cathode and anode plates in the battery cell roll is eliminated; Step S6.2: The outer clamping roller clamps the battery cell roll at the outer side, and the inner clamping needle is pulled away from the battery cell roll.

[0064] When the winding needle drives the initial cell roll 8 to flip to the unloading position, the cutting mechanism cuts off the diaphragm 7 at the unloading position, and the initial cell roll 8 on the winding needle forms a shaped cell roll 9. In this patent, the unloading clamping needle mechanism includes an inner clamping needle. After the initial cell roll 8 on the winding needle forms a shaped cell roll 9, the inner clamping needle extends into the shaped cell roll 9 and applies a force to the shaped cell roll 9 from the inside, thereby stretching the shaped cell roll 9, separating the shaped cell roll 9 from the winding needle, and then facilitating the removal of the winding needle from the shaped cell roll 9.

[0065] In the previous embodiment, it is mentioned that if the misalignment of the tabs of the current battery cell roll is within the range of the standard misalignment, the step of adjusting the unwinding tension of the diaphragm 7 by the tension adjustment mechanism 4 is skipped, and the battery cell roll on the winding needle is directly flipped to the unloading position by the flipping mechanism.

[0066] If the misalignment of the tabs of the current battery cell roll exceeds the range of the standard misalignment, the tension of the unwinding diaphragm 7 is adjusted through the tension adjustment mechanism 4, so that when the flipping mechanism flips the battery cell roll on the winding needle to the unloading position, a force is applied to the battery cell roll through the diaphragm 7, so that the tabs 10 of the multi-layer cathode and anode sheets in the battery cell roll are relatively displaced, and the misalignment of the tabs in the battery cell roll is adjusted to the standard misalignment.

[0067] Therefore, the residual misalignment of the tabs of the formed cell roll 9 at the unloading position is less than or equal to the standard misalignment. The inner clamping needle applies force to the formed cell roll 9 from the inside, and when the formed cell roll 9 is stretched open, the tabs 10 of the multi-layer cathode and anode tabs in the formed cell roll 9 will have a certain degree of relative displacement, thereby eliminating the residual misalignment of the tabs in the formed cell roll 9, making the formed cell roll 9 meet the standard of a qualified cell roll, further improving the winding yield of the cell roll, and reducing production costs.

[0068] In this patent, the unloading clamping needle mechanism also includes an outer clamping roller. After the winding needle is pulled out from the formed battery cell roll 9, the outer clamping roller clamps the formed battery cell roll 9 on the outside, thereby facilitating the inner clamping needle to be pulled out from the formed battery cell roll 9, thereby realizing the unloading of the formed battery cell roll 9 and completing the production of the battery cell roll.

[0069] The contents described above may be implemented individually or in combination in various ways, and these variations are all within the protection scope of the present invention.

[0070] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device comprising the elements.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery cell winding method capable of adjusting the misalignment of the tabs, characterized in that: The following steps are involved: Step S1: unwinding the cathode electrode sheet, the anode electrode sheet and the separator (7) onto a winding needle; Step S2: the coil is wound around the cathode electrode sheet, the anode electrode sheet and the separator (7) to form a battery cell coil, wherein the separator (7) separates the cathode electrode sheet from the anode electrode sheet; Step S3: obtaining the misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll, and comparing the obtained misalignment of the tabs with the standard misalignment; Step S4: according to the comparison result of the tab misalignment amount and the standard misalignment amount, the tension adjustment mechanism (4) adjusts the unwinding tension of the diaphragm (7); Step S5: the turning mechanism operates to drive the winding needle to turn over, and the winding needle drives the battery cell winding to turn over; Step S6: unloading the battery cell roll on the winding needle through the unloading needle clamping mechanism.

2. A battery cell winding method with adjustable tab misalignment as claimed in claim 1, characterized in that: Obtaining the misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll, including: The misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll is measured by a CCD visual detection unit to obtain a numerical value of the misalignment of the tabs.

3. A battery cell winding method with adjustable tab misalignment as claimed in claim 1, characterized in that: The obtained tab misalignment amount is compared with the standard misalignment amount, including: Determine whether the tab misalignment exceeds the standard misalignment. If the tab misalignment exceeds the standard misalignment, execute step S4; if the tab misalignment does not exceed the standard misalignment, skip step S4 and execute step S5.

4. A battery cell winding method with adjustable tab misalignment as claimed in claim 3, characterized in that: The standard misalignment is D1, the tab misalignment is D2, the difference between the tab misalignment and the standard misalignment is △D, △D= D2- D1, step S4 includes: Step S4.1: deriving a relationship between the ΔD and the tension F of the diaphragm (7) during unwinding by means of data fitting; Step S4.2: recording the current value of ΔD, and calculating the value of the tension F of the unwinding of the diaphragm (7) according to the current value of ΔD by using a relational expression; Step S4.3: adjusting the unwinding tension F of the diaphragm (7) to the calculated value through the tension adjustment mechanism (4).

5. A battery cell winding method with adjustable tab misalignment as claimed in claim 1, characterized in that: Step S1 includes: Step S1.1: Unwind the first layer of diaphragm onto the winding needle through the first diaphragm unwinding mechanism Step S1.2: unwinding the cathode electrode sheet onto the winding needle through the cathode electrode sheet unwinding mechanism; Step S1.3: unwinding the second layer of diaphragm onto the winding needle through the second diaphragm unwinding mechanism; Step S1.4: unwinding the anode electrode sheet onto the winding needle through the anode electrode sheet unwinding mechanism.

6. A battery cell winding method with adjustable tab misalignment as claimed in claim 5, characterized in that: The first diaphragm unwinding mechanism and the second diaphragm unwinding mechanism both comprise a diaphragm unwinding shaft (5) and a diaphragm roller (6), the tension adjustment mechanism (4) being arranged between the diaphragm roller (6) and the winding needle, and step S1.2 comprises: The membrane unwinding shaft (5) outputs the membrane (7), and the membrane (7) is wound on the winding needle after passing through the membrane roller (6) and the tension adjustment mechanism (4) in sequence.

7. A battery cell winding method with adjustable tab misalignment as claimed in claim 1, characterized in that: The battery cell roll comprises an initial battery cell roll (8), and step S2 comprises: The winding needle rotates around its own axis to roll together the cathode electrode sheet, the anode electrode sheet and the separator (7) of a certain length to form the initial battery cell roll (8).

8. A battery cell winding method with adjustable tab misalignment as claimed in claim 7, characterized in that: The battery cell roll also includes a shaped battery cell roll (9), the turning mechanism includes a turntable (3), the winding needle is arranged at a position deviating from the axis of the turntable (3), and step S5 includes: Step S5.1: the turntable (3) rotates around its own axis, driving the winding needle to flip around the axis of the turntable (3), and the winding needle drives the initial battery cell roll (8) to flip around the axis of the turntable (3); Step S5.2: cutting the separator (7) on the initial battery cell roll (8) by means of a cutting mechanism to form the formed battery cell roll (9).

9. A battery cell winding method with adjustable tab misalignment as claimed in claim 8, characterized in that: The turntable (3) is provided with a working position and a material discharge position, the winding needle comprises a first winding needle (1) and a second winding needle (2), initially, the first winding needle (1) is located at the working position, and the second winding needle (2) is located at the material discharge position, and step S5.1 comprises: The turntable (3) rotates around its own axis, driving the first winding needle (1) and the second winding needle (2) to turn around the axis of the turntable (3) synchronously, so that the first winding needle (1) turns from the working position to the unloading position, and the second winding needle (2) turns from the unloading position to the working position, and the first winding needle (1) drives the initial battery cell roll (8) to turn from the working position to the unloading position.

10. A battery cell winding method with adjustable tab misalignment as claimed in claim 1, characterized in that: The blanking clamping needle mechanism includes an inner clamping needle and an outer clamping roller, and step S6 includes: Step S6.1: the inner clamping needle extends into the battery cell roll and stretches the battery cell roll to separate the battery cell roll from the winding needle, and the winding needle is pulled out of the battery cell roll. In the process of the inner clamping needle stretching the battery cell roll, the residual misalignment of the tabs of the cathode electrode sheet and the anode electrode sheet in the battery cell roll is eliminated; Step S6.2: The outer clamping roller clamps the battery cell roll at the outer side, and pulls the inner clamping needle away from the battery cell roll.

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