Tab structure of laminated battery

Abstract

The utility model relates to a tab structure of a laminated battery, which comprises sequentially laminated foils, a foil tab led out from the foils is provided with a welding area, the welding area comprises a horn mouth area at the leading-out end of the foil tab and a laminated plane area extending from the horn mouth, and a welding protection sheet is arranged on the upper surface of the laminated plane area. The welding protection sheet comprises a protection section and a welding section, the protection section and the welding section are integrally connected in a right-angle shape to form an L-shaped structure, the welding section of the welding protection sheet is arranged on the upper surface of the stacking plane area of the welding area, and the protection section of the welding protection sheet is arranged at the joint of the horn mouth and the stacking plane area. And a lug is arranged on the lower surface of the laminated plane area of the welding area. According to the utility model, the L-shaped welding protection sheet is adopted, so that the protection sheet is not in contact with the welding horn mouth, and the foil tab is not pressed during welding, thereby effectively avoiding the fracture of the foil tab in the welding process, improving the production quality of the battery and prolonging the service life of the battery.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and particularly to a tab structure for a stacked battery. Background Technology

[0002] In battery manufacturing technology, especially in the manufacturing process of stacked batteries, tab welding is a critical step. The quality of tab welding directly affects the battery's performance and lifespan. However, the high temperature and pressure during the welding process can damage the foil tabs and even cause them to break.

[0003] Existing solutions primarily involve improving welding equipment and processes to reduce heat and pressure during welding, while adding a welding protective sheet on the opposite side of the tab to prevent breakage of the foil tab. Patent document CN107671414 B discloses an ultrasonic welding method for lithium-ion battery tabs and a tab welding protection method. A protective sheet is placed on the ultrasonic welding area of ​​the stacked tab foil, and the welding head of the ultrasonic welding device is pressed onto the protective sheet for ultrasonic welding. Patent document CN 113451712 B discloses a tab structure, a battery, a tab welding method, and an apparatus thereof. The tab structure includes tabs, foil, and a protective sheet stacked sequentially. Welding areas are provided in the tabs, foil, and protective sheet, and the welding areas include weld holes, through which the tabs, foil, and protective sheet are connected. In the embodiments of this application, the tab structure includes tabs, foil, and a protective sheet stacked sequentially. The tabs, foil, and protective sheet are provided with soldering zones, which include solder holes, and the tabs, foil, and protective sheet are connected through the solder holes.

[0004] Existing technical solutions still have problems in practical applications. First, these improvements require high equipment costs and complex operating procedures, which undoubtedly increases production costs and management difficulty; second, such as Figure 3 As shown, for high-energy, high-power batteries, there are more electrode layers and the foil is thinner. The edge of the welding protective sheet still exerts additional pressure on the flared position of the foil tab, causing the outer layer of the foil tab to break during welding.

[0005] Therefore, there is an urgent need to develop a foil electrode structure that can fundamentally solve the breakage problem during the welding process. Utility Model Content

[0006] This invention aims to overcome the shortcomings of the prior art by providing a tab structure for a stacked battery. During the welding process, an L-shaped welding protective sheet is used to effectively prevent the foil tabs from breaking.

[0007] To achieve the above objectives, this utility model provides a tab structure for a stacked battery, comprising sequentially stacked foil materials. The foil tabs extending from the foil materials are provided with a welding area. The welding area includes a flared end of the foil tab and a stacked planar area extending from the flared end. A welding protective sheet is placed on the upper surface of the stacked planar area. The welding protective sheet includes a protective section and a welding section, which are integrally connected at right angles to form an L-shaped structure. The welding section of the welding protective sheet is placed on the upper surface of the stacked planar area of ​​the welding area, and the protective section of the welding protective sheet is placed at the junction of the flared end and the stacked planar area. A tab is placed on the lower surface of the stacked planar area of ​​the welding area.

[0008] Preferably, the length of the welding protective sheet is ≤ 2-3 mm of the electrode welding length, the width is > 2 mm of the welding width, and the thickness is 0.1 mm.

[0009] Preferably, the welding protective sheet is made of aluminum or copper.

[0010] Preferably, the length of the protective section of the welding protective sheet is less than the length of the beveled surface of the flared end of the foil electrode lead-out.

[0011] Preferably, after welding, the protective section of the welding protective sheet is smoothed and made into contact with the beveled surface of the flared end of the foil electrode tab.

[0012] Beneficial effects: Compared with the prior art, this utility model adopts an L-shaped welding protective sheet, which makes the protective sheet non-contact with the welding flared mouth, and does not put pressure on the foil tab during welding, thereby effectively avoiding the breakage of the foil tab during the welding process, improving the production quality and service life of the battery; the structure is simple and easy to implement, which can not only improve the production efficiency of the battery, but also reduce the production cost of the battery, and can be used in conjunction with other welding equipment and processes. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the welding protection sheet of this utility model placed at the welding part of the foil electrode tab;

[0014] Figure 2 yes Figure 1 Schematic diagram of the smoothed-out state of the welding protective sheet;

[0015] Figure 3 This is a schematic diagram of the state of foil tabs in the welding process of existing technology.

[0016] In the diagram: 1. Foil material, 2. Foil tab, 3. Welding area, 3-1. Trumpet area, 3-2. Stacked plane area, 3-3. Joint between trumpet and stacked plane areas, 4. Welding protective sheet, 4-1. Protective section, 4-2. Welding section, 5. Tab. Detailed Implementation

[0017] The following detailed description of the specific embodiments provided by the present invention, in conjunction with preferred embodiments, is as follows: Referring to the accompanying drawings, this embodiment provides a tab structure for a stacked battery, comprising sequentially stacked foil materials 1. A foil tab 2 extending from the foil material is provided with a welding area 3. The welding area includes a flared end area 3-1 at the foil tab's lead-out end and a stacked planar area 3-2 extending from the flared end. A welding protective sheet 4 is placed on the upper surface of the stacked planar area. The welding protective sheet includes a protective section 4-1 and a welding section 4-2, which are connected integrally at right angles to form an L-shaped structure. The welding section of the welding protective sheet is placed on the upper surface of the stacked planar area of ​​the welding area, and the protective section of the welding protective sheet is placed at the junction 3-3 of the flared end and the stacked planar area. A tab 5 is placed on the lower surface of the stacked planar area of ​​the welding area.

[0018] In a preferred embodiment, the length of the welding protective sheet is ≤ 2-3 mm of the electrode welding length, the width is > 2 mm of the welding width, and the thickness is 0.1 mm.

[0019] In a preferred embodiment, the welding protective sheet is made of aluminum or copper. In this embodiment, the positive electrode is made of aluminum, and the negative electrode is made of copper.

[0020] In a preferred embodiment, the length of the protective section of the welding protective sheet is less than the length of the beveled surface of the flared end of the foil tab.

[0021] In a preferred embodiment, after welding, the protective section of the welding protective sheet is smoothed and brought into contact with the beveled surface of the flared end of the foil tab. Smoothing the upright protective section prevents the protective sheet from puncturing the packaging.

[0022] The workflow is as follows:

[0023] Step 1: Prepare the materials and equipment required for welding the tabs of the stacked battery cells. This includes L-shaped welding protective sheets, foil tabs (such as copper foil, aluminum foil, etc.), and tab welding equipment (such as laser welding machines, ultrasonic welding machines, etc.).

[0024] Step 2: Place the L-shaped welding protective sheet on the welding part of the upper surface of the foil electrode tab welding area, ensuring that the protective sheet does not contact the welding flared mouth, and place the electrode tab on the lower surface of the foil electrode tab welding area;

[0025] Step 3: Set the welding parameters: welding current 10A, welding time 2 seconds, welding temperature 200℃. These parameters can be adjusted according to actual needs.

[0026] Step 4: Start the welding equipment and weld the foil tabs. During this process, carefully observe the condition of the foil tabs. If any abnormality is found, stop welding immediately and inspect and adjust accordingly.

[0027] Step 5: After welding is completed, check the welding quality of the foil tabs. If there are any problems, they should be repaired in time.

[0028] Step 6: As Figure 2 Smooth the upright protective sheet to prevent it from puncturing the packaging.

[0029] For the welding of tabs in pad-type batteries, the above steps involve using an L-shaped welding protective sheet to ensure that the protective sheet does not come into contact with the foil tab's flared end during the welding process, thereby avoiding the risk of the foil tab at the flared end breaking due to pressure from the edge of the protective sheet during the welding process.

[0030] The detailed description of the tab structure of a stacked battery with reference to the embodiments is illustrative rather than limiting. Several embodiments may be listed according to the defined scope. Therefore, changes and modifications without departing from the overall concept of this utility model should be within the protection scope of this utility model.

Claims

1. A tab structure for a stacked battery, characterized in that: The device comprises stacked foil materials, with foil tabs extending from the foil materials having a welding area. The welding area includes a flared end area at the foil tab's lead-out end and a stacked planar area extending from the flared end. A welding protective sheet is placed on the upper surface of the stacked planar area. The welding protective sheet includes a protective section and a welding section, which are connected integrally at right angles to form an L-shaped structure. The welding section of the welding protective sheet is placed on the upper surface of the stacked planar area of ​​the welding area, and the protective section of the welding protective sheet is placed at the junction of the flared end and the stacked planar area. An electrode tab is placed on the lower surface of the stacked planar area of ​​the welding area.

2. The tab structure of the stacked battery according to claim 1, characterized in that: The length of the welding protective sheet is ≤ 2-3 mm of the electrode welding length, the width is > 2 mm of the welding width, and the thickness is 0.1 mm.

3. The tab structure of the stacked battery according to claim 1 or 2, characterized in that: The welding protective sheet is made of aluminum or copper.

4. The tab structure of the stacked battery according to claim 3, characterized in that: The length of the protective section of the welding protective sheet is less than the length of the beveled surface of the flared end of the foil electrode lead-out.

5. The tab structure of the stacked battery according to claim 4, characterized in that: After welding, the protective section of the welding protective sheet is smoothed and made into contact with the beveled surface of the flared end of the foil electrode tab.

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