CN112467229A

CN112467229A - Battery cell winding device and method

Info

Publication number: CN112467229A
Application number: CN202011181270.9A
Authority: CN
Inventors: 邱毅; 万志永; 刘声强
Original assignee: Suzhou Jieruisi Intelligent Technology Co ltd
Current assignee: Suzhou Jieruisi Intelligent Technology Co ltd
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-03-09

Abstract

The invention discloses a battery cell winding device, which is used for winding a first diaphragm, a negative plate, a second diaphragm and a positive plate which are sequentially arranged into a battery cell. The battery cell winding device comprises a rotating tower rotating around a mandrel, wherein a winding station, a rubberizing station and a discharging station are sequentially arranged on the circumference of the rotating tower with the mandrel as the circle center, an included angle between every two adjacent stations is 120 degrees, and each station is respectively provided with a winding needle set. And the upstream of the winding station is provided with a pole piece feeding mechanism corresponding to the negative pole piece and the positive pole piece respectively, so that the negative pole piece and the positive pole piece can enter a winding needle group of the winding station actively. The invention can effectively reduce the waiting time before the winding of the battery cell and improve the winding efficiency. The invention also discloses a battery cell winding method for the battery cell winding device.

Description

Battery cell winding device and method

Technical Field

The invention relates to the technical field of lithium battery processing, in particular to a winding device and a method for preparing a lithium battery cell.

Background

The existing lithium battery core rolling is mainly completed by a core winder, and the core winder forms the lithium battery core by stacking, winding and gluing a positive pole piece, a negative pole piece and a diaphragm according to a certain order. In order to increase the production speed of the electrical core winding machine, the existing electrical core winding machine generally adopts a three-station winding head.

Chinese utility model patent No. ZL201921466132.8 entitled "to drawing needle formula electric core winding head, coiling mechanism and button-type electric core film-making winder" discloses a winding head is last to be provided with three group's winding needle units that can work independently promptly. The winding needle unit comprises a first winding needle and a second winding needle which are coaxially arranged, and the two winding needles can move in an opposite direction or in an opposite direction so as to clamp the material belt to wind or release the formed battery cell to complete blanking.

After the winding of the pole piece diaphragm is completed by the first winding needle, the first winding needle can rotate to the second station from the first station so as to glue the wound battery cell. When the first winding needle rotates from the first station to the second station, the second winding needle rotates from the third station to the first station to prepare for winding of the next battery cell; and the third winding needle rotates from the second station to the third station to prepare for detaching the battery core on the third winding needle.

Disclosure of Invention

In order to further improve the efficiency of cell winding, the invention provides a cell winding device and a method for winding a cell by using the cell winding mode.

The battery cell winding device is used for winding a first diaphragm, a negative plate, a second diaphragm and a positive plate which are sequentially arranged into a battery cell. The device includes around a rotatory capstan head of dabber, the capstan head use set gradually coiling station, rubberizing station and unloading station on the circumference of dabber as the centre of a circle, and the contained angle between two adjacent stations is 120 degrees, and every station sets up a book needle group respectively, the upper reaches of coiling station corresponds negative pole piece and positive plate set up a pole piece pan feeding mechanism respectively, initiatively realize that negative pole piece and positive plate get into the book needle group of coiling station.

In the electric core winding device, the pole piece feeding mechanism comprises a driving roller driven to rotate and a driven roller arranged opposite to the driving roller, and the driven roller is driven to be close to and far away from the driving roller.

In an embodiment of the present invention, the pole piece feeding mechanism is integrally disposed at an output end of a second driving mechanism, and moves in a width direction of the pole piece through the second driving mechanism.

In another embodiment of the invention, the winding station and the taping station are substantially aligned in the feed direction of the separator.

In another embodiment of the invention, two film combining rollers are oppositely arranged at the upstream of the winding station, and the film combining rollers can be driven to relatively close to and move away from; wherein connect a draw-in groove on the power supply of a membrane roller together, the relative one side of draw-in groove sets up the cutter, draw-in groove and cutter are located between coiling station and the rubberizing station, and are located the both sides of coiling station and rubberizing station line.

The battery cell winding method provided by the invention is characterized in that a battery cell winding device is utilized to wind a material belt consisting of a first diaphragm, a negative plate, a second diaphragm and a positive plate which are sequentially arranged into a battery cell. The battery cell winding device comprises a turret rotating around a mandrel, a winding station, a rubberizing station and a blanking station are sequentially arranged on the circumference of the turret with the mandrel as the circle center, and the included angle between every two adjacent stations is 120 degrees; each station is respectively provided with a winding needle group, and the winding needle group comprises a first winding needle and a second winding needle which are used for clamping the material belt from two sides; the material belt sequentially passes through a winding station, a rubberizing station and a discharging station to realize winding, rubberizing and discharging of the battery cell. The negative plate and the positive plate are driven to enter between the first winding needle and the second winding needle of the winding station.

In the cell winding method, the first diaphragm, the negative plate, the second diaphragm and the positive plate are sequentially arranged above the turret in a clockwise direction; the winding station and the rubberizing station are basically aligned in the feeding direction of the negative plate and the positive plate.

In the cell winding method, the first winding needle and the second winding needle are retracted in opposite directions at the blanking station to release the cell to complete cell blanking, and then one of the first winding needle and the second winding needle completes a first needle discharging operation before being shifted to the winding station, and the first diaphragm and the second diaphragm are attached to each other.

In the cell winding method, the other of the first winding needle and the second winding needle completes the second needle discharging operation after the other of the first winding needle and the second winding needle is switched to the winding station, and the winding needle group clamps the first diaphragm and the second diaphragm.

In the cell winding method, a film combining roller for pressing the diaphragm/pole piece into a material belt is arranged at the upstream of the winding station, the film combining roller is relatively separated in the process of switching the station by a turret so as to release the material belt, and the film combining roller moves oppositely after the station switching is finished so as to realize the attachment of the material belt; the winding needle group is prior to the film combining roller to realize the attachment of the material belt.

In the cell winding method, at least one winding roller is arranged at the winding station to abut against the cell to ensure that the cell is not loosened in the winding process, and the winding roller moves to the front of the rotation direction of the winding needle group and is in contact with the winding needle group while performing the second needle discharging operation.

According to the embodiments of the invention, the efficiency and the quality of the transposition of the turret can be improved by actively feeding the pole pieces and adjusting the relative directions of the winding station, the rubberizing station and the material belt; the film combining is directly realized by adopting the winding needle, so that the waiting time before the electric core is wound can be reduced. In addition, the arrangement of the groove/the cutter can further reduce the cutting time of the diaphragm, so that the winding efficiency of the battery cell is improved.

Drawings

Fig. 1 is a schematic view of a cell winding apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a pole piece feeding structure in the embodiment shown in FIG. 1;

FIG. 3 is a schematic view of the embodiment of FIG. 1 at a taping station.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Referring to fig. 1, the winding apparatus 100 of the present embodiment includes a turret 20 rotating around a mandrel 10, the turret 20 is provided with a winding station 21, a gluing station 22, and a blanking station 23 arranged in a clockwise direction, the three stations are distributed on a circumference centering on the mandrel 10, and an included angle between the two stations is 120 degrees, so that it can be ensured that the turret 20 can be switched to another station every time it rotates by the same angle, which is convenient to control.

A set of needles 24 is vertically disposed at each station. The needle winding group 24 includes a first winding needle 24a and a second winding needle 24b arranged in parallel, and the first and second winding needles 24a/24b can be driven to extend perpendicularly to the surface of the turret 20 at the corresponding stations or retract from the extending state, respectively. When the first and second winding needles 24a/24b are in the extended state, a gap is formed between the two winding needles for a tape to pass through. The winding needle group 24 can clamp the material belt, and when the winding needle group 24 is driven by a power source to rotate, the material belt can be wound into a battery cell. After the winding of the battery cell is completed, the turret 20 rotates clockwise by 120 degrees around the mandrel 10, and the wound battery cell can be shifted to the rubberizing station 22. The rubberizing station 22 mainly performs rubberizing on the battery cell wound at the winding station 21 to prevent the battery cell after winding and forming from scattering. After the processing at the rubberizing station 22 is completed, the turret 20 continues to rotate by 120 degrees, so that the winding needle group 24 at the station carries the battery cell to switch to a blanking station, the battery cell is clamped by a manipulator (not shown), the first winding needle 24a and the second winding needle 24b are respectively retracted in the axial direction by a driving force to release the battery cell, and then the battery cell is taken away and transferred to other devices or processing units. After the battery core is completely blanked, the turret 20 continues to rotate by 120 degrees, the coiling needle group 24 which is completely blanked is switched to the coiling station 21, and the coiling operation is restarted. Such as a loop.

The rotation, needle withdrawing and needle retracting operations of the first and second winding needles 24a/24b can be realized by a direct drive motor, a slip ring motor or a traditional motor driven speed reducing device. As a preferred embodiment, the needle withdrawing operation and the retracting operation are respectively and independently driven so as to improve the response speed and the precision of the actions. The related art is disclosed in the chinese patent application No. 202010256443.2 filed by the applicant, and is not described herein.

As shown in fig. 1, the tape for winding the battery cell includes a first separator 1, a negative electrode sheet 2, a second separator 3, and a positive electrode sheet 4, which are sequentially arranged above a turret 20 in a clockwise direction. Each set of separator and pole pieces is transferred to a winding needle 24 of a winding station 21 under the action of a corresponding feeding roller (not shown) to form a cell. A pair of film combining rollers 40a and 40b are arranged at the upstream of the winding station 21, and the two film combining rollers 40a and 40b face each other under the action of driving force so as to clamp and keep the first diaphragm 1, the negative pole piece 2, the second diaphragm 3 and the positive pole piece 4 aligned to form a material belt, so that the quality of a wound battery core is ensured. When the turntable switches the working positions, the two film combining rollers 40a and 40b are separated relatively, so that the material belt is prevented from being excessively tensioned to generate wrinkles in the transposition process.

The present embodiment suggests that the driving force of the film rolls 40a, 40b is implemented by selecting a motor, and other power sources such as an air cylinder can also achieve the same effect.

Referring to fig. 2, a pole piece feeding mechanism is disposed between the material tray of the negative pole piece 2 and the film combining rollers 40a/40b, and the mechanism includes a driving roller 2a and a driven roller 2b disposed opposite to each other on two sides of the negative pole piece 2. The driven roller 2b is provided to an output end of a first driving mechanism 2d so as to be driven away from the driving roller 2a along the slide rail 2e to allow the negative electrode sheet 2 to pass through a gap between the driving roller 2a and the driven roller 2b, and the driven roller 2b is driven close to the driving roller 2a to pinch the negative electrode sheet 2.

The drive roller 2a is connected to a motor shaft of a servo motor 2c via a transmission belt 2 f. When the negative pole piece 2 is clamped by the driven roller 2b and the driving roller 2a, the servo motor 2c drives the driving roller 2a to rotate, and then the feeding of the pole piece can be actively completed. After the feeding is completed, the servo motor 2c no longer drives the driving roller 2a to rotate, and the negative electrode sheet 2 is delivered to the winding needle group 24 by the winding traction force of the winding station 21.

The whole pole piece feeding mechanism is arranged on a mounting plate 2h, the mounting plate 2h is arranged at the output end of the second driving mechanism 2j, and therefore the pole piece feeding mechanism can be integrally driven to move along the width direction of the pole piece through the second driving mechanism 2j, the cathode piece 2 is adjusted to be aligned with the diaphragms 1 and 3, and the function of deviation correction of the material belt is achieved. The second driving mechanism 2j is arranged on a large plate (not shown) of the winding machine through a mounting plate 2k, and the

mounting plates

2h and 2k realize stable and accurate relative motion through a sliding rail and a drag chain; the mounting plate 2h is also mounted to the large plate of the winder at the end remote from the mounting plate 2k by means of a number of slide rail mechanisms 2m to maintain stable mounting of the feeding mechanism.

The first and second driving mechanisms can be realized by adopting an air cylinder or a motor/screw rod scheme; the servo motor 2c may drive the driving roller 2a through a transmission belt, or may directly drive the driving roller 2a through a transmission device such as a gear or a direct drive motor, and a person skilled in the art may flexibly select an implementation scheme according to specific needs, which is not limited in this embodiment.

The positive plate 4 is also correspondingly provided with the same mechanisms such as a driving roller 4a, a driven roller 4b, a servo motor 4c and the like to realize the operations of feeding, deviation correction and the like, and the description is not repeated.

Still referring to fig. 1, in the present embodiment, a windup roller 30 is disposed adjacent to the winding station 21 of the turret 20. The wind-up roller 30 is connected to the output of a power source so that its position relative to the winding station can be adjusted. The wind-up roll 30 abuts against the outer surface of the winding needle group 24 at the winding station 21, so that the battery cell wound on the winding needle group 24 cannot be loosened in the winding process, and therefore, along with the continuous increase of the radius of the battery cell, the wind-up roll 30 continuously returns to the adjustment position under the driving of a power source thereof. When the winding of the battery cell is completed, the winding roller 30 is away from the winding needle group 24 to leave an indexing space of the turret 20.

Depending on the specific requirements, the turret 20 may provide one or more take-up rollers 30 for the winding station 21 to abut the cells from different angles, maintaining their quality during the winding process. In this embodiment, the power source of the wind-up roll 30 is realized by selecting a cylinder, and the piston rod of the cylinder drives the wind-up roll 30 to realize stable motion along a set of slide rail mechanism. In other embodiments, the screw rod can be driven by a motor. After the winding of the battery cell is completed, the pole pieces 2 and 4 are cut off, the turret 20 rotates clockwise by 120 degrees, and the battery cell is shifted to the rubberizing station 22 to complete the ending winding and rubberizing procedures of the diaphragms 1 and 3.

In this embodiment, the rubberizing station 22 is substantially right below the winding station 21, and the second membrane 3 in the tape is wound on the cell in the vertical direction to the winding station 21, so that the direction of the tape feeding is substantially the same as the winding station 21 and the rubberizing station 22. The arrangement can ensure that the material belt generates as little transverse displacement as possible in the process of station switching, and ensure the material belt to be neatly attached, thereby improving the clamping quality of the material belt by the winding needle group 24 newly transposed to the winding station 21.

The "substantially" same direction is so-called because in the practical design of the turret mechanism, the winding station is usually at a slight angle to the strip of material so that the strip of material abuts against the initial contact surface with the set of winding needles 24.

In the present embodiment, since the rubberizing station 22 is vertically below the winding station 21 and both

stations

21, 22 are on the right side of the mandrel 10, when the cell is switched from the winding station 21 to the rubberizing station 22, the turret 20 rotates in a clockwise direction. To improve the cell winding efficiency, the cell winding of the winding needle set 24 is counterclockwise, opposite to the rotation direction of the turret 20.

In other embodiments, if the stations of the turret 20 are arranged counterclockwise, that is, when the winding station 21 and the rubberizing station 22 are vertically arranged on the left side of the mandrel 10, the indexing direction of the turret 20 is counterclockwise, and the winding direction of the battery cell should be clockwise. In this case, the arrangement positions of the diaphragm and the pole piece are adjusted to meet the product standard.

Referring to fig. 3, a groove/cutter structure is provided between the winding station 21 and the pasting station 22, and the groove 51 is provided on the motor of the film combining roller 40 a. When the battery cell is transposed to the rubberizing station 22, the winding needle group 24 originally located at the blanking station 23 returns to the winding station, and at this time, when the pair of film combining rollers 40a/40b which are relatively separated due to the transposition of the turret 20 move in opposite directions, the motor also drives the groove 51 to move in the same way along with the corresponding film combining roller 40 a. Since the material tape of this embodiment is fed in a vertical direction and the winding station 21 and the taping station 22 are substantially in the same vertical direction as the material tape, the groove 51 abuts the material tape from just one side when the film combining rollers 40a/40b grip the material tape. Because the material belt is already supported tightly by the groove 51 from one side, the cutter 52 can quickly implement cutting operation from the other side of the material belt with high quality, and the defects of diaphragm wire drawing, cutter service life shortening and the like are avoided.

After the cell finishes the procedure of applying the final product at the adhesive applying station 22, the cell is immediately driven by the turret 20 to rotate 120 degrees to enter the blanking station 23. At this station, a manipulator (not shown) holds the cell, and the first winding needle 24a and the second winding needle 24b are retracted from the winding state by the driving force, so that the cell is released from being fixed. The first winding needle 24a and the second winding needle 24b of the embodiment respectively withdraw from the battery core from opposite directions, so that the friction force applied to the winding membrane contacting with the winding needles at the center of the battery core can be kept balanced in opposite directions, and the phenomenon that the membrane is pulled out or crumpled is avoided.

Subsequently, during the process of changing the winding needle group 24 from the blanking station 23 to the winding station 21, the first winding needle 24a on the left side of the blanking station 23 performs needle withdrawing before changing to the winding station 21, which is referred to as a first needle withdrawing operation, and the second winding needle 24b on the right side maintains a retracted state. In the indexing process, the first winding needle 21a first contacts and attaches the first membrane 1 to the second membrane 3 from the left side in the rotation direction of the turret 20, thereby completing the film combining operation. After the two diaphragms 1 and 3 are combined under the action of the first winding needle 21a, the second winding needle 21b finishes the needle discharging rapidly, which is called as a second needle discharging operation. Simultaneously with the second needle-out operation, the winding-up roller 30 is driven by the driving cylinder to move and contact the first winding needle 24a in front of the rotation direction of the winding needle group 24, so that when the winding needle group 24 starts to rotate, the winding-up roller 30 can press the material belt at the first time, and the winding process is started quickly.

At this time, the first and second winding needles 21a and 21b fixedly clamp the material tape formed by the two separators, and the winding roll 30, the negative electrode sheet 2 and the positive electrode sheet 4 actively enter the winding station under the action of the respective feeding driving mechanisms to start a new cell winding operation. The process is also important for improving the winding efficiency, because the traditional pole piece feeding is realized by utilizing the friction force between the diaphragm and the pole piece, the accurate and reliable feeding cannot be ensured, and the winding needle is often required to stop running to check and confirm whether the feeding is successful or not after the negative pole piece and the positive pole piece are respectively fed. The embodiment adopts an active feeding mode to well ensure the feeding reliability.

In the process of merging films by using the winding needle, the merging rollers 40a/40b also merge films in the opposite movement. But because the speed of the winding needle for realizing the film merging is high, the time can be saved compared with the operation of waiting for the film merging roller to be in place and then driving the needle out. During the second needle-out operation, the wind-up roller 30 is also driven in place synchronously to start the winding process as soon as possible, improving efficiency.

The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.

Claims

1. A battery cell winding device is used for winding a first diaphragm, a negative plate, a second diaphragm and a positive plate which are sequentially arranged into a battery cell and comprises a rotating tower rotating around a mandrel, a winding station, an adhesive application station and a blanking station are sequentially arranged on the circumference of the rotating tower with the mandrel as the circle center, the included angle between every two adjacent stations is 120 degrees, and each station is respectively provided with a coil needle group.

2. The cell winding device according to claim 1, wherein the pole piece feeding mechanism includes a driving roller driven to rotate and a driven roller disposed opposite to the driving roller, and the driven roller is driven to move closer to and away from the driving roller.

3. The cell winding device according to claim 2, wherein the pole piece feeding mechanism is integrally disposed at an output end of a second driving mechanism and is moved in a width direction of the pole piece by the second driving mechanism.

4. The cell winding apparatus of claim 1, wherein the winding station and the taping station are substantially aligned in the feed direction of the separator.

5. The cell winding device of claim 4, wherein the laminating rollers are drivable relatively closer and farther; wherein connect a draw-in groove on the power supply of a membrane roller together, the relative one side of draw-in groove sets up the cutter, draw-in groove and cutter are located between coiling station and the rubberizing station, and are located the both sides of coiling station and rubberizing station line.

6. The cell winding device of claim 1, wherein the winding needle set comprises a first winding needle and a second winding needle, and the first winding needle and the second winding needle are retracted from the blanking station in opposite directions to release the wound cells.

7. A battery cell winding method comprises the steps that a battery cell winding device is utilized to wind a material belt consisting of a first diaphragm, a negative plate, a second diaphragm and a positive plate which are sequentially arranged into a battery cell, the battery cell winding device comprises a rotating tower rotating around a core shaft, a winding station, an adhesive application station and a blanking station are sequentially arranged on the circumference of the rotating tower with the core shaft as the circle center, and the included angle between every two adjacent stations is 120 degrees; each station is respectively provided with a winding needle group, and the winding needle group comprises a first winding needle and a second winding needle which are used for clamping the material belt from two sides; the material belt sequentially passes through a winding station, a rubberizing station and a discharging station to realize winding, rubberizing and discharging of the battery cell, and is characterized in that the negative pole piece and the positive pole piece are driven to enter a group of film combining rollers and the first diaphragm and the second diaphragm form the material belt, and the material belt is fed between a first winding needle and a second winding needle of the winding station through the film combining rollers.

8. The cell winding method according to claim 7, wherein the first separator, the negative electrode sheet, the second separator and the positive electrode sheet are sequentially arranged above the turret in a clockwise direction; the winding station and the rubberizing station are basically aligned in the feeding direction of the negative plate and the positive plate.

9. The cell winding method according to claim 7, wherein the first winding needle and the second winding needle are retracted in opposite directions at a blanking station to release the cell to complete blanking of the cell, and then one of the first winding needle and the second winding needle completes a first needle withdrawing operation before being shifted to the winding station, so that the first separator is attached to the second separator; and the other one of the first winding needle and the second winding needle completes second needle discharging operation after the other one of the first winding needle and the second winding needle is transposed to the winding station, and the winding needle group clamps the first diaphragm and the second diaphragm.

10. The cell winding method according to claim 9, wherein the winding station is provided with at least one winding roller to abut against the cell to ensure that the cell is not loosened during the winding process, and the winding roller moves ahead of the rotation direction of the winding needle group and contacts with the winding needle group simultaneously with the second needle discharging operation.