A lithium battery thermal composite structure
By employing a process in lithium batteries where the positive electrode is thermally bonded to the separator on both sides and stacked with the negative electrode, the problem of high short-circuit rate in existing technologies is solved, achieving the effect of reducing scrap rate and cost.
Patent Information
- Application Number
- CN202520410745.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2026-06-05
- Estimated Expiration
- 2035-03-10
AI Technical Summary
In existing lithium battery thermal bonding processes, the thermal bonding processes of negative electrode and separator or positive and negative electrode and separator have problems such as high short circuit rate, resulting in high scrap rate and increased cost.
The positive electrode sheet is thermally bonded to the separator on both the top and bottom surfaces to form a thermally bonded positive electrode sheet, which is then stacked with the negative electrode sheet. The separator is then cut with a hot cutter to form a single thermally bonded positive electrode sheet. The sheet is processed using a cutting and stacking integrated machine, combined with CCD detection and robotic arm operation to ensure product quality.
This effectively reduced the short-circuit rate of stacked cores, improved the product qualification rate, and reduced production costs.
Smart Images
Figure CN224328721U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of stacking process and equipment, specifically to a thermal composite structure for lithium batteries. Background Technology
[0002] Lithium-ion battery thermal bonding involves first unwinding, cutting, and dust removal of the positive electrode roll (after tab die-cutting), then thermally bonding individual positive electrode sheets with the separator, maintaining a fixed spacing between each positive electrode sheet. The separator is then cut with a hot cutter, ensuring that both sides of the positive electrode sheet are tightly bonded to the separator. This process includes dust removal and static electricity elimination, resulting in a tight bond between the separator and the positive electrode sheet without air bubbles; no powder shedding from the electrode sheet, and no damage to its appearance.
[0003] The existing technology in the industry is a process of thermally bonding the negative electrode sheet and the separator; there is also a process of thermally bonding both the positive and negative electrode sheets with the separator at the same time.
[0004] Both of the above processes result in high short-circuit rates in the stacked cores, leading to high scrap rates and increased manufacturing costs. Utility Model Content
[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a lithium battery thermal recombination structure that can not only achieve the effect of thermal recombination, but also effectively reduce the short circuit rate of stacked cores, improve the yield rate, and reduce costs.
[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: a lithium battery thermal composite structure, including a positive electrode sheet, a negative electrode sheet and a separator, wherein the upper and lower surfaces of the positive electrode sheet are thermally composited with the separator, the positive electrode sheet and the separator form a thermally composite positive electrode sheet, and the thermally composite positive electrode sheet and the negative electrode sheet are stacked.
[0007] Preferably, the thermally composite positive electrode sheet is formed by cutting the separator with a hot cutter to form a single thermally composite positive electrode sheet.
[0008] Preferably, the diaphragm is installed on a cutting and stacking machine.
[0009] The beneficial effects of this utility model are as follows: The structure of this utility model is reasonably designed, which can not only achieve the effect of thermal bonding, but also effectively reduce the short circuit rate of the stacked core, improve the pass rate, and reduce the cost. Attached Figure Description
[0010] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments;
[0011] Figure 1 This is a schematic diagram of the thermal bonding of the upper and lower surfaces of the positive electrode sheet of this utility model;
[0012] Figure 2 This is a schematic diagram of the diaphragm being cut with a hot cutter after thermal bonding according to this utility model;
[0013] Figure 3 This is a schematic diagram of a single thermally composite positive electrode sheet after the diaphragm of this utility model has been cut;
[0014] Figure 4 This is a schematic diagram of the stacking of the thermally composite positive and negative electrode sheets of this utility model. Detailed Implementation
[0015] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.
[0016] Reference Figure 1-4 The specific embodiment adopts the following technical solution: a lithium battery thermal composite structure, including a positive electrode 1, a negative electrode 2 and a separator 3, the upper and lower surfaces of the positive electrode 1 are thermally composited with the separator 3, the positive electrode 1 and the separator 3 form a thermally composite positive electrode 4, and the thermally composite positive electrode 4 is stacked with the negative electrode 2.
[0017] It is worth noting that the thermally composite positive electrode 4 is formed by cutting the separator with a hot cutting knife to form a single thermally composite positive electrode.
[0018] In addition, the diaphragm 3 is installed on the cutting and stacking machine.
[0019] In this specific embodiment, the positive electrode roll (diaphragm) after die-cutting the tabs is installed on the cutting and stacking machine, with one roll at the top and one at the bottom. After unwinding, it is cut into individual sheets. The individual positive electrode sheets are inspected by CCD to remove defective sheets with excessive burrs or poor appearance. The qualified electrode sheets are then fed through a feeding mechanism and a thermal bonding mechanism to thermally bond the diaphragm and the electrode sheet and remove static electricity. Then, the CCD is used to detect the coating size of the diaphragm and the electrode sheet, the electrode sheet spacing, and the insulation resistance. Finally, the diaphragm is cut with a hot cutter. Qualified electrode sheets are processed normally, while NG products are automatically picked out.
[0020] After being cut, the qualified positive electrode sheets are picked up by a robot at one time and stacked with the die-cut negative electrode sheets. The two outermost negative electrode sheets are then wrapped by the separator after stacking. Insulation resistance testing is performed during the process, and unqualified products are picked out. The stacked cores of qualified products enter the hot pressing mechanism for hot pressing, shaping, and insulation resistance testing.
[0021] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A lithium battery thermal composite structure, characterized in that, It includes a positive electrode (1), a negative electrode (2) and a separator (3). The upper and lower surfaces of the positive electrode (1) are thermally bonded to the separator (3). The positive electrode (1) and the separator (3) form a thermally bonded positive electrode (4). The thermally bonded positive electrode (4) is stacked with the negative electrode (2). The thermally bonded positive electrode (4) is formed by cutting the separator with a hot cutter to form a single thermally bonded positive electrode.
2. The lithium battery thermal composite structure according to claim 1, characterized in that, The diaphragm (3) is installed on the cutting and stacking machine.