Pole piece caching device, battery cell winding equipment and pole piece length control method

Abstract

The embodiment of the application discloses a kind of pole piece caching device, battery winding equipment and pole piece length control method, pole piece caching device includes: mounting seat, the mounting seat is spaced apart with two first driving mechanisms in Y direction, each the first driving mechanism is connected with at least one first support, the first support is equipped with caching roller, each the first driving mechanism can drive the first support movement along X direction;Detection mechanism, the detection mechanism is used to detect the length of the pole piece wound by two batteries;The first driving mechanism is electrically connected with the detection mechanism, the first driving mechanism drives the first support corresponding to the length of one of the two first supports according to the detection signal of the detection mechanism Pole piece is moved along X direction, so that the caching roller caches the pole piece of short length. The pole piece length consistency of the two batteries can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of battery production equipment, and particularly relates to a pole piece buffering device, a battery cell winding device and a pole piece length control method. BACKGROUND

[0002] In the production and manufacturing process of lithium batteries, pole pieces (for example, cathode pieces and anode pieces) need to be wound to form battery cells. In order to improve production efficiency, there is a way of synchronously winding two battery cells with one winding needle assembly.

[0003] In the implementation of the application, the inventors have found that the prior art at least has the following problems:

[0004] Due to different pole piece thicknesses, different battery cell winding positions and other factors, the lengths of the pole pieces wound by the two battery cells are different, and such inconsistency in the lengths of the pole pieces will lead to inconsistency in the quality of the battery cells. SUMMARY

[0005] An object of an embodiment of the application is to provide a pole piece buffering device, a battery cell winding device and a pole piece length control method, so as to ensure the consistency of the lengths of the pole pieces.

[0006] According to a first aspect of an embodiment of the application, a pole piece buffering device is provided, comprising:

[0007] a mounting seat, two first driving mechanisms are arranged at intervals in the Y direction of the mounting seat, each first driving mechanism is connected with at least one first support, the first support is provided with a buffering roller, and each first driving mechanism can drive the first support to move along the X direction;

[0008] a detection mechanism, the detection mechanism is used for detecting the lengths of the pole pieces wound by the two battery cells;

[0009] the first driving mechanism is electrically connected with the detection mechanism, the first driving mechanism drives the first support corresponding to the pole piece with a shorter length to move along the X direction according to the detection signal of the detection mechanism, and the buffering roller buffers the pole piece with the shorter length.

[0010] Optionally, the buffering length of the buffering roller buffering the pole piece with the shorter length is equal to the length difference of the pole pieces detected by the detection mechanism.

[0011] Optionally, the pole piece buffering device further comprises a second driving mechanism, the second driving mechanism is connected with the mounting seat, and the second driving mechanism can drive the mounting seat to move along the X direction.

[0012] Optionally, the pole piece buffer device further comprises at least two second supports arranged at intervals along the Y direction, each of the second supports is provided with a rotatable first compression roller, the second supports are slidably connected with the mounting seat along the X direction, and the second supports are provided with first springs.

[0013] Optionally, in the pole piece conveying direction, the at least one first compression roller is located downstream of the buffer roller, the first compression roller located downstream of the buffer roller is installed on the second support through a one-way bearing, and in the state that the first compression roller presses the pole piece, the first compression roller only allows the pole piece to be conveyed downstream in the pole piece conveying direction.

[0014] Optionally, in the Z direction, the first support is provided with a second support on each side.

[0015] Optionally, in the X direction, in the non-working state, the distance between the first compression roller and the mounting seat is greater than the distance between the buffer roller and the mounting seat.

[0016] Optionally, the mounting seat is further provided with a third driving mechanism, the third driving mechanism is connected with a cutter mounting seat, the third driving mechanism can drive the cutter mounting seat to move along the X direction, the cutter mounting seat is provided with two cutters arranged at intervals along the Y direction, the cutters are located upstream of the buffer roller in the pole piece conveying direction, and the two cutters are used to cut off two pole pieces at the same time after the buffer roller buffers the pole pieces with short lengths.

[0017] Optionally, the pole piece buffer device further comprises at least two third supports arranged at intervals along the Y direction, each of the third supports is provided with a rotatable second compression roller, the third supports are slidably connected with the cutter mounting seat along the X direction, the third supports are provided with second springs, and the second compression rollers are located upstream of the cutters in the pole piece conveying direction.

[0018] Optionally, the pole piece buffer device further comprises at least two fourth supports arranged at intervals along the Y direction, each of the fourth supports is provided with a rotatable third compression roller, the fourth supports are slidably connected with the mounting seat or the cutter mounting seat along the X direction, the fourth supports are provided with third springs, and in the non-working state, in the X direction, the distance between the third compression roller and the mounting seat is greater than the distance between the cutters and the mounting seat, and the distance between the second compression roller and the mounting seat is greater than the distance between the cutters and the mounting seat.

[0019] Optionally, the second pressing roller is mounted on the third support through a one-way bearing, the third pressing roller is mounted on the fourth support through a one-way bearing, and in the state that the second pressing roller and the third pressing roller press the pole piece, the second pressing roller only allows the pole piece to be conveyed upstream, and the third pressing roller only allows the pole piece to be conveyed downstream.

[0020] According to a second aspect of the embodiment of the present application, an electric core winding device is provided, comprising:

[0021] The pole piece buffering device as claimed in any of the preceding items;

[0022] A turret is installed with a winding needle assembly, the winding needle assembly has two winding needles that rotate synchronously, and each winding needle is used for winding a pole piece to form an electric core;

[0023] The turret can rotate to make the winding needle assembly be in a winding station or an end-taping station;

[0024] The pole piece buffering device buffers the pole piece between the winding station and the end-taping station.

[0025] Optionally, the turret is further installed with a leaning roller assembly, the leaning roller assembly comprises a first leaning roller and a second leaning roller, and in the working state, the buffering roller is located between the first leaning roller and the second leaning roller.

[0026] Optionally, the first leaning roller and the second leaning roller are closer to the end-taping station than the cutter of the pole piece buffering device, and in the working state, at least one first pressing roller located downstream of the buffering roller presses the pole piece to the second leaning roller in the pole piece conveying direction.

[0027] Optionally, the turret is further installed with a connecting plate, and in the working state, the second pressing roller and the third pressing roller of the pole piece buffering device press the pole piece to the connecting plate, and the cutter of the pole piece buffering device is located between the second pressing roller and the third pressing roller.

[0028] According to a third aspect of the embodiment of the present application, a pole piece length control method using the electric core winding device as claimed in any of the preceding items is provided, comprising:

[0029] Detecting the pole piece lengths of two electric cores wound synchronously by the winding needle assembly;

[0030] When it is detected that the pole piece lengths of the two electric cores are inconsistent, buffering the pole piece corresponding to the electric core with the shorter pole piece length between the winding station and the end-taping station;

[0031] Cutting the pole pieces for winding the two electric cores;

[0032] The rotating winding needle assembly winds tail ends.

[0033] One technical effect of the present application is that the mounting seat is provided with two first driving mechanisms in Y direction, each of the first driving mechanisms is connected with at least one first support, the first support is provided with a buffer roller, each second driving mechanism can drive the first support connected therewith to move in X direction, so as to drive the buffer roller to move in X direction, thus, when the detection mechanism detects that the pole piece wound by one of the battery cells is shorter than the pole piece wound by another battery cell, the first driving mechanism corresponding to the battery cell can drive the buffer roller to extend, so as to buffer the pole piece, after the pole piece is cut off, the pole piece buffered by the buffer roller can be wound to the battery cell, so as to improve the consistency of the length of the pole piece wound by the battery cell.

[0034] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments thereof, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings incorporated in and forming a part of the specification illustrate embodiments of the present application and, together with the description, serve to explain the principles of the application.

[0036] Figure 1 A working principle diagram of a winding needle assembly of an embodiment of the present application;

[0037] Figure 2 A perspective view of a pole piece buffering device of a first embodiment of the present application;

[0038] Figure 3 A front view of the pole piece buffering device of the first embodiment of the present application;

[0039] Figure 4 A top view of the pole piece buffering device of the first embodiment of the present application;

[0040] Figure 5 A working principle diagram of a pole piece winding device of the first embodiment of the present application, at this time, the pole piece buffering device is in a first working state;

[0041] Figure 6 A working principle diagram of the pole piece winding device of the first embodiment of the present application, at this time, the pole piece buffering device is in a second working state;

[0042] Figure 7 A working principle diagram of a pole piece winding device of a second embodiment of the present application.

[0043] 100, needle assembly; 101, first shaft; 102, second shaft; 103, first needle; 104, second needle; 105, first electrode; 106, second electrode; 107, transmission member; 108, bracket; 109, second tab; 200, tab buffer device; 201, mounting seat; 202, first driving mechanism; 203, first support; 204, buffer roller; 205, second driving mechanism; 206, mounting plate; 207, second support; 208, first compression roller; 209, first spring; 210, third driving mechanism; 211, cutter mounting seat; 212, cutter; 213, third support; 214, second compression roller; 215, second spring; 216, fourth support; 217, third compression roller; 218, detection mechanism; 300, electrode winding device; 301, turret; 302, winding station; 303, finishing and taping station; 304, blanking station; 305, roller assembly; 3051, first roller; 3052, second roller; 3053, passing roller; 306, connecting plate. DETAILED DESCRIPTION

[0044] Various exemplary embodiments of the present application will now be described in detail with reference to the figures. It should be noted that the relative arrangements, numerical expressions, and values of the components and steps set forth in these embodiments are not limiting to the scope of the present application unless specifically stated otherwise.

[0045] The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the application or its application or uses.

[0046] Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail herein. However, where appropriate, such techniques, methods, and devices can be viewed as part of the specification and may

[0047] In all of the examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments can have different values.

[0048] It should be noted that like reference numerals and letters refer to like items throughout the several views of the drawings, and that discussion of one item in a drawing does not preclude further discussion of that item in subsequent drawings.

[0049] It should be noted that in the following description, the purpose of the pole piece and the battery cell is only to more clearly describe the working process of the pole piece buffer device and the battery cell winding equipment, and should not be considered as part of any mechanism, assembly, device or equipment. In the following description, each driving mechanism can use a cylinder, a motor, etc. as a power source, and use a piston rod, a worm, etc. for transmission. The specific structure and driving mode of the driving mechanism are known, and will not be described in detail herein.

[0050] As shown in Figure 1 , the support 108 is mounted with a power source (not shown), a turret 301 and a transmission member 107. The needle assembly 100 includes a first winding needle 103 and a second winding needle 104, the first shaft 101 drives the first winding needle 103 to rotate, the second shaft 102 drives the second winding needle 104 to rotate, and the transmission member 107 synchronously transmits power from the power source to the first shaft 101 and the second shaft 102, so that the first winding needle 103 and the second winding needle 104 rotate synchronously, the rotational angular velocity of the two winding needles is the same, the first pole piece is wound on the first winding needle 103 to form a first battery cell 105, and the second pole piece is wound on the second winding needle 104 to form a second battery cell 106. The power source can use a motor, an internal combustion engine, etc. known power output device. The thickness of the first pole piece and the second pole piece is not necessarily the same, since the rotational angular velocity of the first winding needle 103 and the second winding needle 104 is the same, according to V=W*R, the thickness of the pole piece is different, resulting in different R in the winding process, V is not the same, then in the case of synchronous rotation, the length of the pole piece wound by the first battery cell 105 and the second battery cell 106 is different. Wherein, V is the linear velocity of the pole piece winding, W is the angular velocity of the first winding needle 103 and the second winding needle 104, and R is the radius of the battery cell in the winding process.

[0051] As shown in Figures 2 to 4 , the pole piece buffer device 200 includes a mounting seat 201, the mounting seat 201 is provided with two first driving mechanisms 202 in the Y direction, each first driving mechanism 202 is connected with at least one first support 203, each first support 203 is mounted with a buffer roller 204, and each first driving mechanism 202 can drive the first support 203 to move along the X direction, and correspondingly, the buffer roller 204 also moves along the X direction. More specifically, in Figure 2 , each first driving mechanism 202 is connected with two first supports 203, so that each first driving mechanism 202 can simultaneously drive two buffer rollers 204 to move along the X direction. The number of the first support 203 and the buffer roller 204 can be increased or decreased as needed, for example, one or more than two buffer rollers 204 are used, and the more the number of the buffer rollers 204, the longer the length of the pole piece that can be buffered. In Figure 2For clarity, only one first drive mechanism 202 and its connected first support 203 are shown in full, while the first support 203 connected to the other first drive mechanism 202 is omitted.

[0052] like Figure 5 As shown, the electrode sheets are conveyed along the direction indicated by the dotted arrow, with the arrow pointing downstream and the opposite direction upstream. The electrode sheet buffer device 200 also includes a detection mechanism 218, which is used to detect, for example... Figure 1 The lengths of the first electrode wound on the first cell 105 and the second electrode wound on the second cell 106 are shown. When the thicknesses of the first and second electrodes are different, the first electrode will be shorter and the second electrode longer, or vice versa. Two first drive mechanisms 202 are electrically connected to a detection mechanism 218. Based on the detection signal from the detection mechanism 218, the first drive mechanism 202 drives the first support 203 corresponding to the shorter electrode to move along the X direction, causing the buffer roller 204 to buffer the shorter electrode. The detection mechanism 218 can be electrically connected to the first drive mechanism 202 via a control mechanism (not shown). Based on the detection signal from the detection mechanism 218, the control mechanism controls the first drive mechanism 202 corresponding to the shorter electrode to move, driving the connected first support 203 to move along the X direction, causing the buffer roller 204 to press against the electrode for buffering. The detection mechanism 218 can employ known length-measuring components, such as calculating the rotation angle of the roller using a rotary encoder to determine the electrode length. Length detection methods are diverse and will not be described in detail here. The control mechanism can be implemented using various hardware structures such as comparison logic circuits, CMOS circuits, and programmable controllers. The technology of comparing two values ​​to output a drive signal is known and will not be elaborated upon here. The control mechanism can be a separate control mechanism or can be implemented using the control circuit of the first drive mechanism 202 itself, for example, by directly connecting the detection mechanism 218 to the controller of the first drive mechanism 202. Optionally, the buffer length is equal to the length difference between the first and second electrodes detected by the detection mechanism 218, ensuring that the lengths of the first and second electrodes are equal, achieving optimal cell consistency.

[0053] like Figures 1 to 5 As shown, the two first drive mechanisms 202, which are spaced apart in the Y direction, respectively correspond to Figure 1The first electrode tab of the first battery cell 105 and the second electrode tab of the second battery cell 106 are wound. When the length A of the first electrode tab wound by the first battery cell 105 is greater than the length B of the second electrode tab wound by the second battery cell 106, the first driving mechanism 202 corresponding to the second electrode tab drives the first support 203 to move along the X direction, so that the buffer roller 204 moves along the X direction, and a length of the second electrode tab is buffered, and the buffering length can be A-B. Therefore, after the first electrode tab and the second electrode tab are cut off, the second electrode tab buffered at the buffer roller 204 can be wound to the second battery cell 106, so as to compensate for the length difference between the second electrode tab and the first electrode tab, thereby improving the consistency of the lengths of the first electrode tab and the second electrode tab wound by the first battery cell 105 and the second battery cell 106. Correspondingly, the performance consistency of the first battery cell 105 and the second battery cell 106 is also guaranteed. Conversely, if A < B, the first driving mechanism 202 corresponding to the first electrode tab drives the first support 203 to move along the X direction.

[0054] As shown in Figure 3 and Figure 4 , the electrode tab buffering device 200 further comprises a second driving mechanism 205 connected with the mounting seat 201. The second driving mechanism 205 can drive the mounting seat 201 to move along the X direction, so that the electrode tab buffering device 200 enters the working position or exits the working position. More specifically, the second driving mechanism 205 is installed on a mounting plate 206, and the mounting plate 206 is in sliding connection with the mounting seat 201. The active end of the second driving mechanism 205, such as a piston rod, is connected with the mounting seat 201. When the piston rod is extended, the mounting seat 201 will slide along the X positive direction. The present application can also use other forms of driving structure to make the mounting seat 201 move along the X direction, which is not limited in the present application.

[0055] As shown in Figures 2 to 4 , the electrode tab buffering device 200 further comprises at least two second supports 207 arranged in the Y direction. In other words, in the Y direction, one second support 207 corresponds to one first support 203. In order to be clear, Figure 2 and Figure 4 , only one set of second supports 207 is shown in the Y direction in Figure 4The second support 207 above the Y-axis is omitted. Each second support 207 is equipped with a rotatable first pressure roller 208. The second support 207 is slidably engaged with the mounting base 201 in the X-axis, for example, through a guide rod or linear guide. A first spring 209 is provided between the second support 207 and the mounting base 201. The function of the first pressure roller 208 is to ensure that the electrode buffered at the buffer roller 204 can be guided to the needle winding assembly 100 after the electrode is cut. In the electrode conveying direction, at least one first pressure roller 208 is located downstream of the buffer roller 204. The first pressure roller 208 located downstream of the buffer roller 204 is mounted to the second support 207 through a one-way bearing, so that the first pressure roller 208 located downstream of the buffer roller 204 can only rotate in one direction. When the first pressure roller 208 is pressing against the electrode sheet, the first pressure roller 208 only allows the electrode sheet to be conveyed downstream. That is, the electrode sheet buffered at the buffer roller 204 can only be conveyed towards the winding needle assembly 100, and cannot drag the electrode sheet wound on the first winding needle 103 or the second winding needle 104 in the reverse direction.

[0056] like Figure 2 and Figure 3 As shown, in the Z direction, a second support 207 is provided on both sides of the first support 203. In other words, a first pressure roller 208 is provided on both sides of the buffer roller 204, which allows the buffered electrode sheet to be better guided to the winding needle assembly 100.

[0057] like Figure 3 As shown, in the X direction, in the non-working state, the distance between the first pressure roller 208 and the mounting base 201 is greater than the distance between the buffer roller 204 and the mounting base 201. In this way, when working, the first pressure roller 208 can abut against the electrode sheet before the buffer roller 204, so that the electrode sheet will not be displaced during the process of the buffer roller 204 pressing against the electrode sheet.

[0058] like Figures 2 to 4As shown, the mounting base 201 is also provided with a third drive mechanism 210, which is connected to the cutter mounting base 211. Therefore, the third drive mechanism 210 can drive the cutter mounting base 211 to move in the X direction. The cutter mounting base 211 has two cutters 212 spaced apart in the Y direction. The two cutters 212 are used to cut the first electrode and the second electrode, respectively. Since both cutters 212 are mounted on the same cutter mounting base 211, when the third drive mechanism 210 drives the cutter mounting base 211 to extend in the X direction, the two cutters 212 can simultaneously cut the first electrode and the second electrode. That is, the electrode wound on the first battery cell 105 and the second battery cell 106 is cut simultaneously, avoiding the inconsistency in length between the first and second electrode during subsequent winding. In the electrode conveying direction, the cutters 212 are located upstream of the buffer roller 204. The two cutters 212 are used to simultaneously cut the first and second electrode after the buffer roller 204 has buffered the shorter electrode.

[0059] like Figures 2 to 4 As shown, the electrode buffer device 200 also includes at least two third supports 213 spaced apart along the Y direction, each third support 213 being equipped with a rotatable second pressure roller 214. The third support 213 and the cutter mounting base 211 are slidably engaged along the X direction, and a second spring 215 is provided between the third support 213 and the cutter mounting base 211. In the electrode conveying direction, the second pressure roller 214 is located upstream of the cutter 212. The sliding engagement between the third support 213 and the cutter mounting base 211 can be achieved by means of guide rods, linear guides, etc., which will not be described in detail here. The function of the third support 213 is that when the cutter 212 needs to cut the electrode, the third support 213 enables the second pressure roller 214 to press against the electrode upstream of the cutter, thereby ensuring that the cutter 212 can accurately cut the electrode without causing deviation in the length of the buffered electrode.

[0060] like Figures 2 to 4 As shown, the electrode buffer device 200 also includes at least two fourth supports 216 spaced apart along the Y direction. For clarity, Figure 2 and Figure 4Only one fourth support 216 is shown. Each fourth support 216 is mounted with a rotatable third pressing roller 217, and the fourth support 216 is slidingly fitted with the mounting seat 201 or the cutter mounting seat 211 in the X direction, and the slidingly fitted manner can be realized by a guide rod, a wire rail, etc. A third spring (not shown) is arranged between the fourth support 216 and the mounting seat 201 or the cutter mounting seat 211. In a non-working state, in the X direction, the distance between the third pressing roller 217 and the mounting seat 201 is greater than the distance between the cutter 212 and the mounting seat 201, and the distance between the second pressing roller 214 and the mounting seat 201 is greater than the distance between the cutter 212 and the mounting seat 201. The third pressing roller 217 and the second pressing roller 214 can press the pole piece in advance of the cutter 212, thereby ensuring that the pole piece has been flattened and pressed when the cutter 212 cuts the pole piece, and avoiding that the cutter 212 pulls the pole piece to affect the length accuracy.

[0061] Alternatively, the second pressing roller 214 is mounted on the third support 213 through a one-way bearing, and the third pressing roller 217 is mounted on the fourth support 216 through a one-way bearing. In the state that the second pressing roller 214 and the third pressing roller 217 press the pole piece, in the pole piece conveying direction, the second pressing roller 214 only allows the pole piece to be conveyed upstream, and the third pressing roller 217 only allows the pole piece to be conveyed downstream, as shown in Figure 3 and Figure 5 The second pressing roller 214 can only rotate counterclockwise, and the third pressing roller 217 can only rotate clockwise. In this way, before the cutter 212 cuts the pole piece, the second pressing roller 214 and the third pressing roller 217 clamp the pole piece therebetween, ensuring the cutting effect, preventing a section of the pole piece from being dragged out from the material roll upstream of the cutter 212, or from the roll needle assembly 100 downstream of the cutter 212. In addition, compared with the scheme of directly pressing the pole piece with a pressing block, the second pressing roller 214 and the third pressing roller 217 mounted with one-way bearings can avoid pole piece loss on the one hand, and the contact area between the pressing roller and the pole piece is small, and on the other hand, can improve the efficiency of the battery cell winding, so that the roll needle assembly 100 can wind the tail material after the cutter 212 cuts the pole piece, without the third pressing roller 217 leaving the pole piece to wind the tail material again.

[0062] As shown in Figure 3 , in the Z direction, from top to bottom, they are the second pressing roller 214, the cutter 212, the third pressing roller 217, one first pressing roller 208, two buffer rollers 204, and another first pressing roller 208. The advantages of this layout will be described in detail in combination with the working principle below.

[0063] The pole piece buffer device 200 further comprises a detection mechanism 218 and a control mechanism (not shown) as shown in Figure 5 The detection mechanism 218 is used to detect whether the pole piece is in the buffer rollers 204 or not, and the control mechanism is used to control the second pressing roller 214 and the third pressing roller 217 to move in the X direction. Figure 1The length of the first tab wound by the first cell 105 and the length of the second tab wound by the second cell 106. The control mechanism controls the first driving mechanism 202 corresponding to the length of the tab to act according to the detection signal of the detection mechanism 218, so as to drive the first support 203 to extend along the X direction, and the buffer roller 204 buffers the tab with short length.

[0064] As shown in Figure 5 and Figure 6 The cell winding device 300 of the embodiment of the present application comprises:

[0065] The tab buffering device 200 as claimed in any one of the preceding claims;

[0066] The turret 301 is provided with the winding needle assembly 100. More specifically, Figure 5 The winding needle assembly 100 shown in Figure 1 has three in common, but the specific number of the winding needle assembly 100 can be increased or decreased as needed. The winding needle assembly 100 has two winding needles rotating synchronously, which are the first winding needle 103 and the second winding needle 104 as shown in

[0067] The turret 301 has three stations, which are the winding station 302, the end sealing station 303 and the discharging station 304. The winding needle assembly 100 at the winding station 302 winds the tab; the winding needle assembly 100 at the end sealing station 303 can seal the free end of the tab after cutting, and fix the free end of the tab on the cell by the adhesive tape; the cell on the winding needle assembly 100 at the discharging station 304 is taken off to enter the next processing procedure. The turret 301 can rotate to make each winding needle assembly 100 be at the winding station 302 or the end sealing station 303. The tab buffering device 200 buffers the tab between the winding station 302 and the end sealing station 303. Still taking the first cell 105 wound by the first tab with the length A greater than the second tab wound by the second cell 106 with the length B as an example, Figure 1 , Figure 5 , Figure 6 It can be seen that the first driving mechanism 202 corresponding to the second tab 109 drives the buffer roller 204 to extend towards the positive direction of X to press the second tab 109 to enter the end sealing station 303 as shown in Figure 6In the state shown, the length of the second pole piece 109 between the winding station 302 and the end-taping station 303 is elongated, and the elongated distance just compensates for the length difference between the first pole piece and the second pole piece 109, so that the lengths of the pole pieces wound by the first battery cell 105 and the second battery cell 106 are equal at the end-taping station 303.

[0068] As shown in Figure 5 , Figure 6 , the turret 301 is also provided with a back roller assembly 305. The back roller assembly 305 includes a first back roller 3051 and a second back roller 3052. In the second working state shown in Figure 6 , the buffer roller 204 is located between the first back roller 3051 and the second back roller 3052, thereby buffering the second pole piece 109. Since there are two buffer rollers 204 in this embodiment, the back roller assembly 305 further includes an over roller 3053 located between the two buffer rollers 204 to increase the buffering length.

[0069] As shown in Figure 6 , the first back roller 3051 and the second back roller 3052 are closer to the end-taping station 303 than the cutter 212 of the pole piece buffering device 200. In the second working state, at least one first pressing roller 208 located downstream of the buffer roller 204 presses the second pole piece 109 against the second back roller 3052 in the pole piece conveying direction, and the at least one first pressing roller 208 is preferably mounted to the second support 207 by a one-way bearing. In this embodiment, there are two first pressing rollers 208, one of which presses the second pole piece 109 against the first back roller 3051, and the other of which presses the second pole piece 109 against the second back roller 3052. After the cutter 212 cuts the second pole piece 109, the first pressing rollers 208, the first back roller 3051, and the second back roller 3052 guide the buffered length of the second pole piece 109, preventing the free end from falling and causing the position of the pole piece to deviate when the winding ends.

[0070] As shown in Figure 5 and Figure 6 , the turret 301 is also provided with a connecting plate 306. In the working state, the second pressing roller 214 and the third pressing roller 217 of the pole piece buffering device 200 press the second pole piece 109 against the connecting plate 306, and the cutter 212 of the pole piece buffering device 200 is located between the second pressing roller 214 and the third pressing roller 217. The second pressing roller 214 and the third pressing roller 217 flatten the second pole piece 109 at the connecting plate 306, preventing the cutter 212 from pulling the second pole piece 109 during cutting and causing length errors.

[0071] Next, the working process of the pole piece winding device 100 will be described in conjunction with Figures 1 to 6The specific working process of the battery cell winding equipment 300 in this embodiment will be further described in detail.

[0072] Still with Figure 1 Taking the case where the length A of the first electrode plate wound on the first battery cell 105 is greater than the length B of the second electrode plate wound on the second battery cell 106 as an example, after the winding needle assembly 100 completes winding at the winding station 302, the turret 301 rotates, and the winding needle assembly 100 reaches the finishing adhesive application station 303. The second drive mechanism 205 drives the mounting base 201 to move in the positive X direction and enter the working station. The two first pressure rollers 208 abut against the second electrode plate 109, pressing the second electrode plate 109 against the first guide roller 3051 and the second guide roller 3052. Similarly, the two first pressure rollers 208 corresponding to the first electrode plate (not shown) abut against the first electrode plate, pressing the first electrode plate against the first guide roller 3051 and the second guide roller 3052. The first spring 209 plays a buffering role in this process and provides pressure on the electrode plate. The third pressure roller 217 presses the first electrode plate and the second electrode plate 109 against the connecting plate 306. At this time, the first working state is as follows. Figure 5 As shown.

[0073] The detection mechanism 218 detects the length of the electrode sheets wound on the first battery cell 105 and the second battery cell 106 respectively and sends the detection signal to the control mechanism. After the control mechanism compares A>B, it controls the first drive mechanism 202 corresponding to the second electrode sheet 109 to drive the first support 203 and its buffer roller 204 to move in the positive X direction. The buffer roller 204 further presses against the second electrode sheet 109. Since the third pressure roller 217 and the first pressure roller 208 are both rotatable, the upstream second electrode sheet 109 can be further conveyed between the winding station 302 and the finishing adhesive application station 303. The second electrode sheet 109 is buffered by the buffer roller 204 for a certain length. Optionally, this buffer length is equal to AB, that is, the buffer length of the electrode sheet buffering device 200 for the electrode sheet between the winding station 302 and the finishing adhesive application station 303 is equal to the difference in electrode sheet length detected by the detection mechanism 218. At this time, the second working state is as follows. Figure 6 As shown. Even if there is a deviation between the buffer length and AB, the presence of the buffer length can still improve the consistency of the battery cells.

[0074] Next, the third drive mechanism 210 drives the cutter mounting base 211 to move along the positive X direction. The second pressure roller 214 and the third pressure roller 217 together flatten the first electrode and the second electrode 109 on the connecting plate 306. The second spring 215 acts as a buffer and provides resistance to the electrode. Then, the cutter 212 simultaneously cuts the first electrode and the second electrode 109. At this time, the distance between the free end of the first electrode and the first cell 105 is less than the distance between the free end of the second electrode 109 and the second cell 106 by a buffer length, which exactly makes up for the length difference between A and B.

[0075] Finally, the winding needle assembly 100 rotates to wind the free end of the pole piece, and the free end of the first pole piece and the free end of the second pole piece are respectively pasted to the first battery cell 105 and the second battery cell 106, at this time, the length of the pole piece wound on the first battery cell 105 and the second battery cell 106 is the same.

[0076] As shown in the second embodiment of the present application, each first driving mechanism 202 only drives one buffer roller 204, and the buffer roller 204 buffers the second pole piece 109 between the first supporting roller 3051 and the second supporting roller 3052. Figure 7

[0077] The embodiment of the present application also provides a pole piece length control method, which comprises:

[0078] Detecting the first pole piece length of the first battery cell 105 and the second pole piece length of the second battery cell 106 synchronously wound by the winding needle assembly 100.

[0079] When it is detected that the first pole piece length is inconsistent with the second pole piece length, buffering the pole piece corresponding to the battery cell with shorter pole piece length between the winding station 302 and the end pasting station 303, and the buffering length is equal to the pole piece length difference between the two battery cells. In the embodiment, the length B of the second pole piece 109 is smaller than the length A of the first pole piece, but if the length A of the first pole piece is smaller than the length B of the second pole piece, the first pole piece will be buffered, so the method is still applicable.

[0080] After the pole piece buffering is completed, the pole pieces wound to form the two battery cells are cut off, and in the embodiment, one cutter mounting seat 211 drives two cutters 212 to synchronously cut off the first pole piece and the second pole piece.

[0081] Finally, the winding needle assembly 100 rotates to wind the tail. More specifically, the free end of the first pole piece and the free end of the second pole piece will be wound, and the buffered part of the second pole piece 109 will also be wound in the process, so as to make up for the length difference with the first pole piece.

[0082] ​For the consistency of the performance of the battery cell, the length of the pole piece has a greater impact, even if the first battery cell 105 and the second battery cell 106 are wound to have the same radius, the difference in the thickness of the pole piece will still cause the length of the pole piece wound by the two battery cells to be different, assuming that the thickness of the first pole piece is twice the thickness of the second pole piece (only an extreme example), when the first winding is completed, the radii R of the two battery cells are already different, the radius R of the first battery cell 105 is greater than the radius R of the second battery cell 106, when the second winding is completed, if the radius of the winding needle itself is ignored, the length of the second pole piece wound by the first battery cell 105 will be close to twice the length of the second pole piece wound by the second battery cell 106, and as the number of windings increases, the difference in the radius will further increase. If only the difference in the radius is compensated, even if the radius of the second battery cell 106 is wound to be the same as the radius of the first battery cell 105, due to the difference in the thickness of the pole piece, the length of the first pole piece and the length of the second pole piece are still different. The embodiments of the present application detect the length of the pole piece as the standard, and finally improve the consistency of the length of the pole piece wound by the two battery cells.

[0083] The above embodiments mainly describe the differences between the various embodiments, and the optimization features different between the various embodiments can be combined to form a better embodiment without contradiction. In view of the brevity of the writing, the above will not be repeated here.

[0084] Although some specific embodiments of the present application have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration and are not intended to limit the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. An electrode core winding apparatus (300) characterized by comprising: The application relates to a pole piece buffer device (200) and a turret (301). The pole piece buffer device (200) comprises: a mounting base (201) provided with two first driving mechanisms (202) at intervals in the Y direction, each first driving mechanism (202) being connected with at least one first support (203), the first support (203) being provided with a buffer roller (204), and each first driving mechanism (202) being capable of driving the first support (203) to move along the X direction; a detection mechanism (218) for detecting the length of pole pieces wound by two electric cores; the first driving mechanism (202) is electrically connected with the detection mechanism (218), and the first driving mechanism (202) drives the first support (203) corresponding to the pole piece with a shorter length to move along the X direction according to the detection signal of the detection mechanism (218), so that the buffer roller (204) buffers the pole piece with a shorter length; at least two second supports (207) are provided at intervals in the Y direction, and each second support (207) is provided with a rotatable first compression roller (208); the turret (301) is provided with a winding needle assembly (100), and the turret (301) can rotate to make the winding needle assembly (100) be in a winding position (302) or an end-taping position (303); the pole piece buffer device (200) buffers the pole pieces between the winding position (302) and the end-taping position (303). The buffer length of the buffer roller (204) buffering the pole piece with a shorter length is equal to the length difference of the pole pieces detected by the detection mechanism (218).

2. The cell winding apparatus according to claim 1, characterized by, The pole piece buffer device further comprises a second driving mechanism (205) connected with the mounting base (201), and the second driving mechanism (205) can drive the mounting base (201) to move along the X direction.

3. The cell winding apparatus according to claim 1, characterized by, The second support (207) is slidably connected with the mounting base (201) in the X direction, and a first spring (209) is arranged between the second support (207) and the mounting base (201).

4. The cell winding apparatus according to claim 1, characterized by, In the pole piece conveying direction, at least one first compression roller (208) is located downstream of the buffer roller (204), the first compression roller (208) located downstream of the buffer roller (204) is installed on the second support (207) through a one-way bearing, and in the state that the first compression roller (208) presses the pole piece, the first compression roller (208) only allows the pole piece to be conveyed downstream in the pole piece conveying direction.

5. The cell winding apparatus according to claim 4, characterized by, In the Z direction, the two sides of the first support (203) are both provided with the second support (207).

6. The cell winding apparatus according to claim 4, characterized by, In the X direction, in the non-working state, the distance between the first compression roller (208) and the mounting base (201) is greater than the distance between the buffer roller (204) and the mounting base (201).

7. The cell winding apparatus according to claim 4, characterized by, ​ 8. The cell winding apparatus according to claim 1, characterized by, The mounting base (201) is further provided with a third driving mechanism (210) connected with a cutter mounting base (211), the third driving mechanism (210) can drive the cutter mounting base (211) to move along the X direction, two cutters (212) are arranged at intervals along the Y direction on the cutter mounting base (211), and the cutters (212) are located upstream of the buffer roller (204) in the conveying direction of the pole piece, and the two cutters (212) are used for cutting two pole pieces at the same time after the buffer roller (204) buffers the pole pieces with short lengths.

9. The cell winding apparatus according to claim 8, characterized by, The pole piece buffer device further comprises at least two third supports (213) arranged at intervals along the Y direction, each of the third supports (213) is provided with a rotatable second compression roller (214), the third supports (213) are in sliding fit along the X direction with the cutter mounting base (211), and the second spring (215) is arranged between the third supports (213) and the cutter mounting base (211), and the second compression roller (214) is located upstream of the cutters (212) in the conveying direction of the pole piece.

10. The cell winding apparatus according to claim 9, characterized by, The pole piece buffer device further comprises at least two fourth supports (216) arranged at intervals along the Y direction, each of the fourth supports (216) is provided with a rotatable third compression roller (217), the fourth supports (216) are in sliding fit along the X direction with the mounting base (201) or the cutter mounting base (211), a third spring is arranged between the fourth supports (216) and the mounting base (201) or the cutter mounting base (211), and in the non-working state, the distance between the third compression roller (217) and the mounting base (201) is greater than the distance between the cutters (212) and the mounting base (201) in the X direction, and the distance between the second compression roller (214) and the mounting base (201) is greater than the distance between the cutters (212) and the mounting base (201) in the X direction.

11. The cell winding apparatus according to claim 10, characterized by, The second compression roller (214) is installed on the third support (213) through a one-way bearing, the third compression roller (217) is installed on the fourth support (216) through a one-way bearing, and in the state that the second compression roller (214) and the third compression roller (217) press the pole piece, the second compression roller (214) only allows the pole piece to be conveyed upstream and the third compression roller (217) only allows the pole piece to be conveyed downstream in the conveying direction of the pole piece.

12. The cell winding apparatus (300) according to claim 1, characterized by, The winding needle assembly (100) has two winding needles rotating synchronously, and each winding needle is used for winding the pole piece to form an electric core.

13. The cell winding apparatus according to claim 1, characterized by, The turret (301) is further provided with a backup roller assembly (305), the backup roller assembly (305) comprises a first backup roller (3051) and a second backup roller (3052), and in the working state, the buffer roller (204) is located between the first backup roller (3051) and the second backup roller (3052).

14. The cell winding apparatus according to claim 13, characterized by, The first and second backup rollers (3051, 3052) are closer to the end taping station (303) than the cutter (212) of the pole piece buffer device (200), and in the working state, at least one first pressing roller (208) downstream of the buffer roller (204) presses the pole piece to the second backup roller (3052) in the pole piece conveying direction.

15. The cell winding apparatus according to claim 13, characterized by, The turret (301) is also provided with a connecting plate (306), and in the working state, the second pressing roller (214) and the third pressing roller (217) of the pole piece buffer device (200) press the pole piece to the connecting plate (306), and the cutter (212) of the pole piece buffer device (200) is located between the second pressing roller (214) and the third pressing roller (217).

16. A method of controlling the length of a tab applied to the jelly-roll apparatus of any one of claims 1 to 15, characterized by, Comprise: Detect the length of the pole piece of the two electric cores synchronously wound by the winding needle assembly (100); When it is detected that the lengths of the pole pieces of the two electric cores are inconsistent, the pole piece corresponding to the electric core with shorter pole piece length is buffered between the winding station (302) and the end taping station (303); Cut off the pole pieces wound to form the two electric cores; The winding needle assembly (100) rotates to wind the tail material, and the buffered part of the pole piece is wound.

Images