An electrode assembly for a lithium secondary battery

Abstract

The utility model discloses a kind of electric core winding devices, including winding mechanism, insert piece mechanism, unwinding mechanism and winding mechanism. The winding mechanism is used to form the winding of the polar piece and diaphragm layering electric core, insert piece mechanism is set to the upstream of winding mechanism, for the polar piece insertion winding mechanism. The unwinding mechanism is set to the upstream of insert piece mechanism, for the polar piece of film protection membrane output to winding mechanism. The winding mechanism is set between unwinding mechanism and insert piece mechanism, for receiving the protective film on the polar piece. The electric core winding device of the utility model is through optimizing structure layout, setting winding mechanism between unwinding mechanism and insert piece mechanism, realize the automatic peeling and winding of protective film, improve production efficiency and electric core quality.

Description

Technical Field

[0001] This utility model belongs to the field of lithium battery automation equipment, and in particular relates to a cell manufacturing equipment. Background Technology

[0002] In the manufacturing process of lithium metal batteries, the metal anode (such as ultra-thin lithium foil) is highly chemically active and has low mechanical strength, making it extremely susceptible to oxidation or mechanical damage in the air, which can affect battery performance. Therefore, it is usually necessary to attach a temporary protective film (such as PMMA, PET, etc.) to prevent oxidation, mechanical damage or contamination.

[0003] However, the temporary protective film cannot be wound into the cell along with the negative electrode strip. Therefore, the temporary protective film needs to be removed before the negative electrode strip is loaded into the cell manufacturing equipment. But removing the protective film too early can lead to the oxidation of lithium metal, and also carries the risk of introducing impurities and causing damage. Utility Model Content

[0004] To address the technical problems existing in the prior art, this utility model provides a battery cell winding device that can protect the negative electrode strip from damage to the greatest extent.

[0005] To achieve the above objectives, the present invention provides a battery cell winding device comprising:

[0006] An unwinding mechanism for unwinding an electrode sheet, at least one side of which is covered with a protective film;

[0007] A winding mechanism for winding the electrode sheets to form a battery cell;

[0008] An insertion mechanism is provided between the unwinding mechanism and the winding mechanism for inserting the electrode sheet into the winding mechanism;

[0009] A winding mechanism is disposed between the unwinding mechanism and the inserting mechanism for receiving the protective film.

[0010] In one embodiment of the battery cell winding device of this utility model, the winding mechanism is disposed on one side of the unwinding mechanism to directly receive the protective film on the electrode sheet output from the unwinding mechanism.

[0011] In one embodiment of the battery cell winding device of this utility model, the winding mechanism is disposed upstream of the inserting mechanism and is used to receive the protective film before the electrode sheet is conveyed to the inserting mechanism.

[0012] In one embodiment of the battery cell winding device of this utility model, the winding mechanism is disposed on one side of the insert mechanism.

[0013] In one embodiment of the battery cell winding device of this utility model, a spare unwinding mechanism is provided on one side of the unwinding mechanism, and the spare unwinding mechanism and the unwinding mechanism work alternately.

[0014] In one embodiment of the battery cell winding device of this utility model, a connecting mechanism is provided between the unwinding mechanism and the inserting mechanism for connecting the electrode sheet being transported and the electrode sheet released by the standby unwinding mechanism.

[0015] In one embodiment of the battery cell winding device of this utility model, a tension adjustment mechanism is provided between the unwinding mechanism and the inserting mechanism for adjusting the tension of the electrode sheet; and the tension adjustment mechanism is configured as a tension swing rod.

[0016] In one embodiment of the battery cell winding device of this utility model, a belt-carrying monitoring mechanism is provided between the unwinding mechanism and the inserting mechanism for recording the length of the electrode sheet and detecting the tension of the electrode sheet.

[0017] In one embodiment of the battery cell winding device of this utility model, a correction mechanism is provided between the unwinding mechanism and the inserting mechanism to detect the offset of the electrode sheet and correct it; the correction mechanism is configured as a serpentine correction mechanism.

[0018] In one embodiment of the battery cell winding device of this utility model, the winding mechanism includes a rotary motor, a film clamping shaft, and a clamping assembly. The film clamping shaft is connected to the rotary motor, and at least one arc-shaped groove is provided on the outer surface of the film clamping shaft along its axial direction. The clamping assembly is provided with a pin that cooperates with the arc-shaped groove. The pin cooperates with the arc-shaped groove to clamp the starting end of the protective film.

[0019] In summary, this utility model of battery cell winding device optimizes the structural layout by setting a winding mechanism between the unwinding mechanism and the inserting mechanism, thereby achieving automatic peeling and winding of the protective film, improving production efficiency and electrode quality. Attached Figure Description

[0020] Figure 1 This is a structural diagram of Embodiment 1 of the present invention;

[0021] Figure 2 yes Figure 1 Structural diagram of the winding mechanism;

[0022] Figure 3 This is a structural diagram of Embodiment 2 of the present invention;

[0023] In the diagram: 10, protective film; 20, electrode sheet; 30, first diaphragm; 40, positive electrode sheet; 50, second diaphragm; 100, unwinding mechanism; 110, spare unwinding mechanism; 200, inserting mechanism; 210, clamping roller; 220, clamping plate; 300, winding mechanism; 400, rewinding mechanism; 410, rotary motor; 420, film clamping shaft; 421, arc groove; 422, second baffle; 430, clamping assembly; 431, pin; 432, first baffle; 433, handle; 500, tape receiving mechanism; 600, tension adjustment mechanism; 700, tape feeding monitoring mechanism; 710, tension assembly; 720, length counting assembly; 800, correction mechanism. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0025] like Figure 1 As shown in the first embodiment of this utility model, the battery cell winding device is provided with an unwinding mechanism 100, an inserting mechanism 200, and a winding mechanism 300 sequentially along the electrode conveying direction. A winding mechanism 400 is provided on one side of the unwinding mechanism 100. The unwinding mechanism 100 is used to unwind the electrode 20 covered with a protective film 10 to the winding mechanism 300, wherein the protective film 10 is received by the winding mechanism 400, and the electrode 20 with the protective film 10 removed is conveyed to the winding mechanism 300 through a series of rollers to produce a battery cell. The inserting mechanism 200 is used to insert the electrode 20 into the winding needle of the winding mechanism 300. A cutting mechanism (not shown) is also provided between the inserting mechanism 200 and the winding mechanism 300. The cutting mechanism is used to cut the electrode 20 when the length of the electrode wound in a battery cell meets a set standard, so as to complete the preparation of a battery cell. The insertion mechanism 200 is used to feed the cut electrode 20 back into the winding mechanism 300 to start the preparation of a new battery cell. The winding mechanism 300 is used to wind the electrode 20 in layers with the separately provided first separator 30, positive electrode 40, and second separator 50 to form a battery cell.

[0026] A spare unwinding mechanism 110 is provided on one side of the unwinding mechanism 100. The unwinding mechanism 100 and the spare unwinding mechanism 110 work alternately to continuously supply electrode sheets 20 to the winding mechanism 300. When the material roll on the unwinding mechanism 100 is about to be unwound, the spare unwinding mechanism 110 replaces the unwinding mechanism 100 to supply electrode sheets 20 downstream.

[0027] A second winding mechanism 400 is provided on one side of the standby unwinding mechanism 110 to receive the protective film 10 on the electrode 20 released by the standby unwinding mechanism 110. The two winding mechanisms 400 are respectively provided on one side of the unwinding mechanism 100 and the standby unwinding mechanism 110, so that after the electrode 20 is unwound from the unwinding mechanism 100 / standby unwinding mechanism 110, the protective film 10 can be directly wound up by the winding mechanism 400, which facilitates the processing or operation of the electrode 20 by the downstream mechanism, i.e., the winding mechanism 300.

[0028] A tape receiving mechanism 500 is provided downstream of the unwinding mechanism 100 to connect the conveyed electrode 20 with the electrode 20 released by the standby unwinding mechanism 110. Two winding mechanisms 400 are respectively provided on one side of the unwinding mechanism 100 and the standby unwinding mechanism 110, so that the tape receiving mechanism 500 can connect the two sides of the conveyed electrode 20 and the electrode 20 released by the standby unwinding mechanism 110, and the tape can be directly pasted onto the electrode 20, resulting in a more secure adhesion.

[0029] Downstream of the winding mechanism 500 is a tension adjustment mechanism 600, which is a tension swing arm used to adjust the tension of the electrode 20. The tension swing arm can swing to drive the electrode 20 to compensate for tension fluctuations before and after winding, thus ensuring winding quality.

[0030] Downstream of the tension adjustment mechanism 600 is a belt transport monitoring mechanism 700, used to record the length of the electrode 20 and detect the tension of the electrode 20. The belt transport monitoring mechanism 700 includes a tension measuring component 710 and a length measuring component 720.

[0031] The tension measuring component 710 can use a known tension measuring component, such as directly connecting to the tension sensor via a roller. The tension of the electrode 20 is converted into pressure on the roller, and the tension value is directly output to the controller. The controller then controls the rotation of the swing arm of the tension adjustment mechanism 600 based on the tension value.

[0032] The length counting component 720 can use a known length counting component, such as calculating the rotation angle of the roller by a rotary encoder, thereby calculating the length of the electrode sheet.

[0033] The forms of length measurement and tension measurement are varied and will not be elaborated further.

[0034] Downstream of the conveyor belt monitoring mechanism 700 is a correction mechanism 800, which is a serpentine correction mechanism used to detect the offset of the electrode 20 and correct it.

[0035] In this embodiment, the protective film 10 is immediately peeled off the electrode 20 unwound by the unwinding mechanism 100. The electrode 20 is transported from the unwinding mechanism 100 to the winding mechanism 300 via a relatively long path, and the electrode 20 is prone to oxidation. The path of the electrode 20 from the unwinding mechanism 100 to the winding mechanism 300 can be set in a closed space filled with inert gas to prevent the electrode 20 from oxidizing.

[0036] like Figure 2 As shown, the winding mechanism 400 includes a rotary motor 410, a film clamping shaft 420, and a clamping assembly 430. The rotary motor 410 is mounted on the large plate of the equipment, and its rotation shaft is connected to the film clamping shaft 420. The outer surface of the film clamping shaft 420 has at least one arc-shaped groove 421 along its axial direction. The clamping assembly 430 is provided with pins 431 that cooperate with the arc-shaped grooves 421. The pins 431 cooperate with the arc-shaped grooves 421 to clamp the starting end of the protective film 10. In this embodiment, two arc-shaped grooves 421 are provided, symmetrically distributed on the outer surface of the film clamping shaft 420; two pins 431 are also provided, and the two pins 431 are connected to a first baffle 432. The surface of the first baffle 432 facing away from the pins 431 is provided with handles 433, and the two pins 431 extend into the arc-shaped grooves 421 from the axial direction of the film clamping shaft 420.

[0037] When the winding mechanism 400 fixes the starting end of the protective film 10, the operator manually moves the starting end of the protective film 10 around the outer surface of the film clamping shaft 420, through the two arc grooves 421, and inserts the two pins 431 of the clamping assembly 430 into the two arc grooves 421 through the handle 433 to clamp the protective film 10.

[0038] A second baffle 422 is provided at one end of the film clamping shaft 420 near the rotary motor 410. After the clamping assembly 430 is inserted into the film clamping shaft 420, the first baffle 432 and the second baffle 422 are located at both ends of the film clamping shaft 420, which limits the winding of the protective film 10, making the winding of the protective film 10 more neat.

[0039] like Figure 3 As shown, this is the second embodiment of the present invention. The difference between this embodiment and the first embodiment is that a single winding mechanism 400 is provided, located upstream of the inserting mechanism 200. The inserting mechanism 200 typically includes two opposing clamping rollers 210, each connected to a clamping plate 220. A cutting mechanism is located between the clamping plate 220 and the winding mechanism 300. When it is necessary to cut the electrode sheet 20, the two clamping rollers 210 are driven to clamp the electrode sheet 20 to facilitate the cutting operation, while preventing the cut electrode sheet 20 from retracting away from the winding mechanism 300 due to tension. The clamping plate 220 protects the electrode sheet from both sides to prevent it from shaking, so as to facilitate the re-feeding of the electrode sheet 20 into the winding mechanism 300.

[0040] In this embodiment, the winding mechanism 400 is located upstream of the insert mechanism 200, and is positioned as close to the insert mechanism 200 as possible, where layout allows. Figure 3 As shown, the electrode 20 is transported from the unwinding mechanism 100 to the insertion mechanism 200 covered by a protective film 10. When it is transported to the insertion mechanism 200, the protective film 10 is guided by a conveying roller and received by the winding mechanism 400. The wound electrode 20 is then directly transported to the insertion mechanism 200.

[0041] To prevent electrode oxidation, the electrode insertion mechanism 200 can also be placed in a closed space filled with inert gas.

[0042] The winding mechanism 400 is located one station upstream of the inserting mechanism 200. It can effectively protect the electrode 20 during the conveyor belt process and avoid problems such as oxidation, wrinkling, and powder shedding of the electrode 20 during the conveyor belt process.

[0043] In addition, in this embodiment, the winding mechanism 400 is located upstream of the insert mechanism 200. Therefore, the tape-connecting mechanism 500 can connect the electrode 20 with the unpeeled protective film 10 during transmission to the electrode 20 with the unpeeled protective film 10 released by the standby unwinding mechanism 110. Adhesive tape is attached to both the protective film 10 and the electrode 20 at the connection point, allowing the protective film 10 to be smoothly wound up by the winding mechanism 400. Compared to the first embodiment of this utility model, one winding mechanism 400 can be saved, reducing the complexity and cost of the equipment.

[0044] In summary, this utility model of battery cell winding device optimizes the structural layout by setting a winding mechanism between the unwinding mechanism and the inserting mechanism, thereby achieving automatic peeling and winding of the protective film, improving production efficiency and winding quality.

[0045] The above description is only a part or preferred embodiment of this application. Neither the text nor the drawings should limit the scope of protection of this application. All equivalent structural transformations made using the content of this application's specification and drawings under the overall concept of this application, or direct / indirect applications in other related technical fields, are included within the scope of protection of this application.

Claims

1. A battery cell winding device, characterized in that, include: An unwinding mechanism for unwinding an electrode sheet, at least one side of which is covered with a protective film; A winding mechanism for winding the electrode sheets to form a battery cell; An insertion mechanism is provided between the unwinding mechanism and the winding mechanism for inserting the electrode sheet into the winding mechanism; A winding mechanism is disposed between the unwinding mechanism and the inserting mechanism for receiving the protective film.

2. The cell winding device as described in claim 1, characterized in that, The winding mechanism is located on one side of the unwinding mechanism to directly receive the protective film on the electrode sheet output from the unwinding mechanism.

3. The cell winding device as described in claim 1, characterized in that, The winding mechanism is located upstream of the inserting mechanism and is used to receive the protective film before the electrode sheet is conveyed to the inserting mechanism.

4. The cell winding device as described in claim 3, characterized in that, The winding mechanism is located on one side of the insert mechanism.

5. The cell winding device as described in claim 1, characterized in that, A backup unwinding mechanism is provided on one side of the unwinding mechanism, and the backup unwinding mechanism and the unwinding mechanism work alternately.

6. The cell winding apparatus as described in claim 5, characterized in that, A connecting mechanism is provided between the unwinding mechanism and the inserting mechanism to connect the electrode sheet being transported with the electrode sheet released by the standby unwinding mechanism.

7. The cell winding device as described in claim 1, characterized in that, A tension adjustment mechanism is provided between the unwinding mechanism and the inserting mechanism to adjust the tension of the electrode sheet; and the tension adjustment mechanism is configured as a tension lever.

8. The cell winding apparatus as described in claim 1, characterized in that, A belt-carrying monitoring mechanism is provided between the unwinding mechanism and the inserting mechanism to record the length of the electrode and detect the tension of the electrode.

9. The cell winding device as described in claim 1, characterized in that, A correction mechanism is provided between the unwinding mechanism and the inserting mechanism to detect and correct the offset of the electrode sheet; the correction mechanism is configured as a serpentine correction mechanism.

10. The cell winding apparatus as described in claim 1, characterized in that, The winding mechanism includes a rotary motor, a film clamping shaft, and a clamping assembly. The film clamping shaft is connected to the rotary motor. The outer surface of the film clamping shaft is provided with at least one arc-shaped groove along its axial direction. The clamping assembly is provided with a pin that cooperates with the arc-shaped groove. The pin cooperates with the arc-shaped groove to clamp the starting end of the protective film.

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