A structure for preventing battery pole piece from wrinkling

Abstract

This utility model discloses a structure for preventing battery electrode wrinkling, relating to the field of battery manufacturing technology. It includes two battery cells and a top cover. Each battery cell has two sets of tabs connected to it. The top cover has a positive terminal and a negative terminal. The two sets of tabs on each battery cell are welded to the positive and negative terminals respectively. Each tab is L-shaped, consisting of a horizontal section and a vertical section. The horizontal section of the tab connects to either the positive or negative terminal, and the vertical section connects to the battery cell's electrode. This utility model changes the tab shape from rectangular or trapezoidal to an L-shaped structure and adds reinforcing ribs to the tab surface, significantly improving stress concentration at the tab location, thereby effectively reducing electrode wrinkling and improving the battery's appearance quality and internal structural stability.

Description

Technical Field

[0001] This utility model relates to the field of battery manufacturing technology, and in particular to a structure for preventing wrinkling of battery electrode sheets. Background Technology

[0002] To reduce the risk of short circuits and avoid heat concentration, the distance between the positive and negative terminals of a lithium battery needs to be as large as possible. This results in the tabs being close to the radius (R) of the electrode core. During tab welding, the electrode sheets are subjected to stress at the tabs, causing severe wrinkling. Furthermore, with the development of high-rate cells, the tab width has increased, leading to the tabs being even closer to the R angle.

[0003] In existing technologies, the tabs of lithium batteries typically employ a rectangular or trapezoidal structure, such as... Figure 4 As shown, during the welding and assembly process, especially when the tabs are close to the R-angle, the stress concentration of the electrode sheet can easily lead to wrinkling. To avoid wrinkling, it is usually necessary to reduce the distance between the positive and negative tabs. However, this is limited by the positive and negative terminals of the battery top cover. Adjusting the terminal spacing is not only complicated and costly, but also prone to creepage if the terminal spacing is too close. In addition, the temperature at the terminals is generally high during battery operation, and the close distance between the positive and negative terminals can easily lead to heat concentration, which poses a safety risk. Therefore, a structure to prevent battery electrode wrinkling is proposed. Utility Model Content

[0004] The purpose of this invention is to solve the problems mentioned in the background art and to propose a structure to prevent battery electrode wrinkling.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A structure for preventing battery electrode wrinkling includes two battery cells and a top cover. Each battery cell is connected to two sets of tabs, and the top cover is provided with a positive terminal and a negative terminal. The two sets of tabs on each battery cell are respectively connected to the positive terminal and the negative terminal by welding.

[0007] Preferably, each of the tabs is an L-shaped structure, consisting of a horizontal section and a vertical section. The horizontal section of the tab is connected to the positive or negative terminal, and the vertical section of the tab is connected to the electrode plate of the battery cell.

[0008] Preferably, each of the tabs is provided with reinforcing ribs on its surface.

[0009] Preferably, the electrode tab is made of copper or aluminum.

[0010] Preferably, the top cover is made of plastic.

[0011] Compared with the prior art, the advantages of this utility model are:

[0012] 1. This utility model changes the shape of the electrode tab from rectangular or trapezoidal to an L-shaped structure and adds reinforcing ribs to the surface of the electrode tab, which significantly improves the stress concentration of the electrode sheet at the electrode tab, thereby effectively improving the wrinkling phenomenon of the electrode sheet and improving the appearance quality and internal structural stability of the battery.

[0013] 2. Without changing the distance between the positive and negative terminals of the top cover, this utility model increases the usable welding area by increasing the length of the horizontal section of the electrode tab, thereby reducing the internal resistance of the battery and meeting the working requirements of high-power batteries. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model.

[0015] Figure 2 This is a schematic diagram of the connection structure between the battery cell and the electrode in this utility model.

[0016] Figure 3 This is a schematic diagram of the electrode tab in this utility model.

[0017] Figure 4 This is a schematic diagram of a comparative structure in the prior art.

[0018] In the diagram: 1. Battery cell, 2. Top cover, 3. Positive terminal, 4. Negative terminal, 5. Tab, 51. Horizontal section, 52. Vertical section. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0020] Reference Figure 1-2 As shown, a structure for preventing battery electrode wrinkling includes two battery cells 1 and a top cover 2. Each battery cell 1 is connected to two sets of tabs 5. The top cover 2 is provided with a positive electrode post 3 and a negative electrode post 4. The two sets of tabs 5 on each battery cell 1 are respectively connected to the positive electrode post 3 and the negative electrode post 4 by welding.

[0021] Each tab 5 has an L-shaped structure, consisting of a horizontal section 51 and a vertical section 52. The horizontal section 51 of the tab 5 is connected to the positive electrode post 3 or the negative electrode post 4, and the vertical section 52 of the tab 5 is connected to the electrode plate of the cell 1. For the cell 1 with a high rate requirement, the length of the horizontal section 51 of the tab 5 can be increased according to the welding area requirement.

[0022] Each tab 5 has a reinforcing rib on its surface. The height of the reinforcing rib is 0.1-0.3 times the thickness of the tab 5, which reduces the deformation of the tab 5 during the winding process.

[0023] The tab 5 is made of copper or aluminum. The tab 5 connected to the positive electrode post 3 is made of aluminum, and the tab 5 connected to the negative electrode post 4 is made of copper.

[0024] The top cover 2 is made of plastic.

[0025] Working process and its principle:

[0026] In use, an electrode sheet with blank edges is used. An L-shaped tab 5 is formed in the blank area by laser die-cutting. Then, the die-cut positive electrode sheet, die-cut negative electrode sheet, and separator are wound together in a winding machine to obtain the cell 1. Subsequently, the horizontal section 51 of the tab 5 is connected and fixed to the positive electrode post 3 or the negative electrode post 4 by laser welding. With the position of the post remaining unchanged, the tab 5 is away from the R-angle of the cell, thereby reducing the risk of the electrode sheet wrinkling. Finally, the top cover 2 of the battery is welded and sealed to form a complete lithium battery.

[0027] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A structure for preventing wrinkling of battery electrode sheets, characterized in that, It includes two battery cells (1) and a top cover (2). Each battery cell (1) is connected to two sets of tabs (5). The top cover (2) is provided with a positive electrode post (3) and a negative electrode post (4). The two sets of tabs (5) on each battery cell (1) are respectively connected to the positive electrode post (3) and the negative electrode post (4) by welding.

2. The structure for preventing battery electrode wrinkling according to claim 1, characterized in that, Each of the tabs (5) is an L-shaped structure, consisting of a horizontal section (51) and a vertical section (52). The horizontal section (51) of the tab (5) is connected to the positive electrode post (3) or the negative electrode post (4), and the vertical section (52) of the tab (5) is connected to the electrode plate of the cell (1).

3. The structure for preventing battery electrode wrinkling according to claim 1, characterized in that, Each of the tabs (5) has a reinforcing rib on its surface.

4. The structure for preventing battery electrode wrinkling according to claim 1, characterized in that, The tab (5) is made of copper or aluminum.

5. The structure for preventing battery electrode wrinkling according to claim 1, characterized in that, The top cover (2) is made of plastic.

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