Battery tab welding equipment

Abstract

The utility model provides battery tab welding equipment which comprises a vacuum box, a jig used for fixing a tab to be welded is arranged in the vacuum box, a welding hole and an air exhaust hole are formed in the side wall of the vacuum box, a quartz glass cover is assembled on the welding hole, and the air exhaust hole is connected to a vacuum pump. The vacuum box comprises a box body and a box cover, the quartz glass cover is arranged on the box cover, and the box cover and the box body are detachably assembled; the battery tab welding equipment further comprises a galvanometer welding head used for transmitting a laser beam, and the laser beam penetrates through the quartz glass cover to the to-be-welded tab on the jig. According to the utility model, a vacuum environment can be provided for tab welding, no protective gas needs to be added, and the vacuum environment can effectively reduce impurities and gas in a tab welding area space, so that the probability of air holes generated in the welding process is reduced, and meanwhile, gas in a molten pool and a key hole can be quickly discharged; and the probability that air holes exist in the tabs after welding can be greatly reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery tab welding device. Background Technology

[0002] As a crucial component within the battery cell, the tabs serve to conduct current and connect the core. Currently, the commonly used welding method is ultrasonic welding between the tabs and the battery cover adapter plate. However, this method is prone to incomplete welds when dealing with thicker tabs, such as those with more than 60 layers. Furthermore, ultrasonic welding utilizes high-frequency vibrations between the tabs and the adapter plate to bond them together, making the edge areas of the tab weld susceptible to breakage or reduced toughness. Therefore, laser welding is now more commonly used.

[0003] However, traditional fiber laser welding of tabs suffers from problems such as numerous internal pores and poor surface quality. Porosity is one of the most concerning issues in battery cell manufacturing. Since the tabs in the battery cell serve to connect the cover plate and transmit current, if there are too many or too large internal pores after tab welding, it will lead to excessive internal resistance when the battery cell experiences overcurrent, causing overheating; at the same time, the strength of the tabs will be reduced, making the tabs or the base of the tabs prone to breakage. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a battery tab welding machine with a simple structure that facilitates the provision of a vacuum environment for tab welding.

[0005] The embodiments of this utility model are achieved through the following technical solutions:

[0006] A battery tab welding device includes a vacuum chamber, inside which a fixture is provided for fixing the tabs to be welded. The side wall of the vacuum chamber has welding holes and an evacuation port. A quartz glass cover is fitted onto the welding holes, and the evacuation port is connected to a vacuum pump. The vacuum chamber includes a body and a cover, with the quartz glass cover mounted on the cover, and the cover and body are detachably assembled. The battery tab welding device also includes a galvanometer welding head for transmitting a laser beam, which passes through the quartz glass cover to the tab to be welded on the fixture.

[0007] According to a preferred embodiment, the fixture includes a base plate on which a battery support and a welding support are disposed. The battery support is used to support the winding core, and the welding support is used to support the electrode tab to be welded. The fixture also includes a pressure block adjustablely disposed on the base plate. The pressure block corresponds to the welding support and can move closer to or further away from the welding support in the longitudinal direction. A welding notch is provided through the pressure block, and the laser beam passes through the welding notch to the electrode tab to be welded.

[0008] According to a preferred embodiment, a longitudinal plate is mounted on the base plate, a first adapter plate is slidably mounted on the side of the longitudinal plate facing the welding support, a pressure block is mounted on the first adapter plate, and a driving member for driving the first adapter plate to move is disposed on the longitudinal plate.

[0009] According to a preferred embodiment, the driving component is a cylinder, and the first adapter plate is slidably mounted on the cylinder body of the electric cylinder or the cylinder.

[0010] According to a preferred embodiment, a second adapter plate is fixedly installed on the first adapter plate, a limit plate is disposed on the second adapter plate, an adapter block is slidably mounted on one side of the second adapter plate facing the welding support, the pressure block is fixedly installed on the adapter block, a guide shaft is mounted on the adapter block, the guide shaft passes through the limit plate and is slidably connected to it, a buffer spring is sleeved on the guide shaft, and the buffer spring is located between the limit plate and the adapter block.

[0011] According to a preferred embodiment, the pressure block includes a fixing part, an extension part, and a shaping part connected in sequence, wherein the extension part is inclined toward the welding support, the shaping part extends toward the welding support, and the welding notch is provided through the shaping part.

[0012] According to a preferred embodiment, the shaping part has a shaping plane on the side facing the welding support; the welding support has a welding plane, the shaping plane is parallel to the welding plane, the welding plane has a clearance groove, and the welding notch and the clearance groove are longitudinally corresponding.

[0013] According to a preferred embodiment, at least one vent hole is provided on the side wall of the welding support, and the vent hole is connected to the clearance groove.

[0014] According to a preferred embodiment, the laser beam spot is a single-mode annular spot, including an inner spot and an annular spot surrounding the inner spot.

[0015] According to a preferred embodiment, the battery support is provided with a first limiting block and a second limiting block, which are used to limit the winding core on the battery support.

[0016] The technical solution of this utility model embodiment has at least the following advantages and beneficial effects:

[0017] This invention provides a vacuum environment for electrode welding, eliminating the need for protective gas. The vacuum environment effectively reduces impurities and gases in the air, thereby reducing the probability of porosity during welding. At the same time, the gas in the molten pool and keyhole can be quickly discharged, which can greatly reduce the probability of porosity inside the electrode after welding. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the assembly structure of the adapter and semi-finished electrode tab provided in this embodiment of the utility model;

[0020] Figure 2 A three-dimensional structural diagram of the vacuum chamber provided for an embodiment of this utility model;

[0021] Figure 3 An exploded view of the vacuum chamber provided in this embodiment of the present invention;

[0022] Figure 4 This is a three-dimensional structural diagram of the fixture after assembling the core according to an embodiment of the present utility model;

[0023] Figure 5 for Figure 4 A partially enlarged schematic diagram of the structure at point A;

[0024] Figure 6 This is a three-dimensional structural diagram of the pressure block provided in an embodiment of the present utility model;

[0025] Figure 7 This is an assembly diagram of the welding support and the battery support.

[0026] Icons: 1. Core; 10. Electrode to be welded; 11. Semi-finished electrode; 12. Adapter; 2. Vacuum box; 21. Box body; 210. Material inlet; 2101. First sealing ring groove; 2102. Second sealing ring groove; 211. Cover plate; 212. Air extraction hole; 22. Box cover; 221. Quartz glass cover; 23. Fixture; 231. Base plate; 232. Battery support; 2321. First limiting block; 2322. Second limiting block; 233. Welding 2331. Support; 2332. Welding plane; 2333. Clearance groove; 2333. Vent hole; 234. Clamping handle; 235. Clamping block; 2350. Fixing part; 2351. Extension part; 2352. Shaping part; 23520. Welding notch; 236. Longitudinal plate; 2361. First adapter plate; 2362. Driving component; 237. Second adapter plate; 2371. Limiting plate; 2372. Guide shaft; 238. Adapter block; 239. Buffer spring. Detailed Implementation

[0027] To better understand and implement this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0030] Please refer to Figures 1 to 7 A battery tab welding device includes a vacuum chamber 2, inside which a fixture 23 is provided for fixing the tab 10 to be welded. The side wall of the vacuum chamber 2 is provided with welding holes and evacuation holes 212. A quartz glass cover 221 is fitted on the welding hole, and the evacuation hole 212 is connected to a vacuum pump (not shown in the figure). The vacuum chamber 2 includes a chamber body 21 and a cover 22. The quartz glass cover 221 is disposed on the cover 22, and the cover 22 and the chamber body 21 are detachably assembled. The battery tab welding device also includes a galvanometer welding head (not shown in the figure) for transmitting a laser beam. The laser beam passes through the quartz glass cover 221 to the tab 10 to be welded on the fixture 23.

[0031] like Figure 1 As shown, the battery tab is composed of layers of 8μm-12μm aluminum foil. The battery tab is pre-welded into a single semi-finished tab 11 using ultrasonic welding, facilitating the subsequent clamping and welding of the battery tab during laser welding. Figure 2 As shown, the adapter 12 is a battery cover plate 211 adapter piece, including an upper adapter piece and a lower adapter piece, with the semi-finished electrode tab 11 located between the upper and lower adapter pieces. In this embodiment, the upper adapter piece, the lower adapter piece, and the semi-finished electrode tab 11 together constitute the aforementioned electrode tab 10 to be welded, which is welded into a single unit using a laser. In this embodiment, the vacuum chamber 2 provides a vacuum welding environment for the electrode tab mounted on the fixture 23 and ensures its airtightness. Preferably, the minimum pressure of the vacuum environment is 1 Pa. Using laser welding in a vacuum environment eliminates the need for adding shielding gas, and the gas in the molten pool and keyhole can be quickly expelled, greatly reducing the probability of porosity inside the electrode tab after welding.

[0032] like Figure 2 and Figure 3 As shown, the lid 22 is detachably assembled to the box body 21 by bolts or screws. The box body 21 is a square box, with a material inlet 210 on one side and a cover plate 211 for sealing the material inlet 210 on the same side. In this embodiment, a first sealing ring groove 2101 is provided around the material inlet 210 on the box body 21, and a second sealing ring groove 2102 is provided around the opening end on the side of the box body 21 facing the lid 22. In use, sealing rings are installed in both the first sealing ring groove 2101 and the second sealing ring groove 2102 to achieve a seal between the box body 21 and the cover plate 211 and the lid 22.

[0033] In this embodiment, the housing 21 and the cover plate 211 are hinged together and secured with a latch. The evacuation port 212 is connected to the vacuum pump via a pipe (not shown in the figure).

[0034] like Figure 4 As shown, the fixture 23 includes a base plate 231, on which a battery support 232 and a welding support 233 are disposed. The battery support 232 is used to support the core 1, and the welding support 233 is used to support the electrode tab 10 to be welded. The fixture 23 also includes a pressure block 235 that is adjustablely disposed on the base plate 231. The pressure block 235 corresponds to the welding support 233 and can move closer to or further away from the welding support 233 in the longitudinal direction. A welding notch 23520 is provided through the pressure block 235, and the laser beam passes through the welding notch 23520 to the electrode tab 10 to be welded. In use, the core 1 is placed on the battery support 232 and pressed and fixed by the clamping handle 234 installed on the battery support 232. At this time, the electrode tab 10 to be welded overlaps the welding support 233 and is pressed and fixed by the pressure block 235. The laser beam passing through the quartz glass cover 221 passes through the welding notch 23520 and completes the welding of the electrode tab 10 to be welded within the area of ​​the welding notch 23520.

[0035] Specifically, a longitudinal plate 236 is mounted on the base plate 231, and a first adapter plate 2361 is slidably mounted on the side of the longitudinal plate 236 facing the welding support 233. A pressure block 235 is mounted on the first adapter plate 2361, and a driving member 2362 for driving the first adapter plate 2361 is disposed on the longitudinal plate 236. Optionally, the driving member 2362 is an electric cylinder or a pneumatic cylinder. In some embodiments, in order to make the fixture 23 compact, the first adapter plate 2361 is slidably mounted on the cylinder body of the electric cylinder or the pneumatic cylinder.

[0036] Furthermore, a second adapter plate 237 is fixedly installed on the first adapter plate 2361. A limit plate 2371 is disposed on the second adapter plate 237. An adapter block 238 is assembled on the side of the second adapter plate 237 facing the welding support 233 via a slide rail slider assembly. A pressure block 235 is fixedly installed on the adapter block 238. A guide shaft 2372 is assembled on the adapter block 238. The guide shaft 2372 passes through the limit plate 2371 and is slidably connected to it. A buffer spring 239 is sleeved on the guide shaft 2372, and the buffer spring 239 is located between the limit plate 2371 and the adapter block 238. Figure 4 and Figure 5 As shown, the adapter block 238 is located below the limiting plate 2371. In use, the driving component 2362 drives the first adapter plate 2361 to move longitudinally, thereby causing the adapter block 238 mounted on the second adapter plate 237 to move longitudinally. When the pressure block 235 abuts against the adapter 12, the pressure block 235, i.e., the adapter block 238, is subjected to force to compress the buffer spring 239 longitudinally upward, realizing the flexible contact between the pressure block 235 and the adapter 12, and preventing the adapter 12 and the semi-finished electrode tab 11 from being damaged.

[0037] like Figure 5 and Figure 6 As shown, the pressure block 235 includes a fixing part 2350, an extension part 2351, and a shaping part 2352 connected in sequence. The extension part 2351 is inclined towards the welding support 233, the shaping part 2352 extends towards the welding support 233, and a welding notch 23520 penetrates the shaping part 2352. In this embodiment, the fixing part 2350 is installed on the adapter block 238 by bolts or screws, and the inclined arrangement of the extension part 2351 towards the welding support 233 prevents the main body of the pressure block 235 from blocking the transmission of the laser beam.

[0038] like Figure 7 As shown, further, the shaping part 2352 has a shaping plane on the side facing the welding support 233; the welding support 233 has a welding plane 2331, the shaping plane is parallel to the welding plane 2331, the welding plane 2331 has a relief groove 2332, and the welding notch 23520 and the relief groove 2332 are longitudinally corresponding. The shaping plane, in conjunction with the welding plane 2331, flattens and fixes the electrode tab 10 to be welded.

[0039] In this embodiment, at least one vent hole 2333 is provided on the side wall of the welding support 233, and the vent hole 2333 is connected to the relief groove 2332. The vent hole 2333 facilitates the balance of temperature and pressure between the relief groove 2332 and the box 21 during welding, which is beneficial to maintaining the structural stability of the electrode tab 10 part to be welded within the area defined by the relief groove 2332 during the welding process.

[0040] In some embodiments, a first limiting block 2321 and a second limiting block 2322 are disposed on the battery support 232, and the first limiting block 2321 and the second limiting block 2322 are used to limit the winding core 1 on the battery support 232.

[0041] In this embodiment, the laser beam spot is a single-mode annular spot, including an inner spot and an annular spot surrounding the inner spot.

[0042] Specifically, the power of the inner spot is 200W-1000W. Preferably, the power of the inner spot is 200W-400W. The power of the ring spot is 300W-1000W. Preferably, the power of the ring spot is 300W-600W. The welding speed of the laser beam spot on the adapter 12 is 100mm / s-500mm / s. Preferably, the welding speed of the laser beam spot on the adapter 12 is 100mm / s-300mm / s.

[0043] Furthermore, the welding trajectory of the laser beam spot on the electrode tab 10 to be welded is spiral, elliptical, or figure-eight shaped. In this embodiment, preferably, the welding trajectory of the laser beam spot on the adapter 12 is spiral. The oscillation amplitude of the galvanometer is 0.1mm-0.4mm. In this embodiment, the inner spot is used to form a deeper penetration depth to form the central region of the molten pool, while the ring spot is used to reduce the temperature gradient at the edge of the molten pool to reduce spatter. Using the combination of the inner and ring spots for welding, combined with a vacuum welding environment, can ensure penetration depth, reduce welding spatter, reduce porosity inside the electrode tab, and ensure the welding quality of the battery electrode tab.

[0044] The technical means disclosed in this utility model are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications are also considered within the scope of protection of this utility model.

Claims

1. A battery tab welding device, characterized in that, The device includes a vacuum chamber, which contains a fixture for fixing the electrode tabs to be welded. The side wall of the vacuum chamber has welding holes and evacuation holes. A quartz glass cover is fitted onto the welding holes, and the evacuation holes are connected to a vacuum pump. The vacuum chamber includes a chamber body and a chamber lid, the quartz glass cover is disposed on the chamber lid, and the chamber lid and the chamber body are detachably assembled; The battery tab welding equipment also includes a galvanometer welding head for transmitting a laser beam, which passes through the quartz glass cover to the tab to be welded on the fixture.

2. The battery tab welding equipment according to claim 1, characterized in that, The fixture includes a base plate, on which a battery support and a welding support are disposed. The battery support is used to support the winding core, and the welding support is used to support the electrode tab to be welded. The fixture also includes an adjustable pressure block disposed on the base plate. The pressure block corresponds to the welding support and can move closer to or further away from the welding support in the longitudinal direction. A welding notch is provided through the pressure block, and the laser beam passes through the welding notch to the electrode to be welded.

3. The battery tab welding equipment according to claim 2, characterized in that, A longitudinal plate is mounted on the base plate, and a first adapter plate is slidably mounted on the side of the longitudinal plate facing the welding support. A pressure block is mounted on the first adapter plate, and a driving component for driving the first adapter plate to move is disposed on the longitudinal plate.

4. The battery tab welding equipment according to claim 3, characterized in that, The driving component is a cylinder, and the first adapter plate is slidably mounted on the cylinder body of the electric cylinder or the cylinder.

5. The battery tab welding equipment according to claim 3, characterized in that, A second adapter plate is fixedly installed on the first adapter plate. A limit plate is configured on the second adapter plate. An adapter block is slidably mounted on one side of the second adapter plate facing the welding support. The pressure block is fixedly installed on the adapter block. A guide shaft is mounted on the adapter block. The guide shaft passes through the limit plate and is slidably connected to it. A buffer spring is sleeved on the guide shaft. The buffer spring is located between the limit plate and the adapter block.

6. The battery tab welding equipment according to claim 2, characterized in that, The pressure block includes a fixing part, an extension part, and a shaping part connected in sequence. The extension part is inclined toward the welding support, the shaping part extends toward the welding support, and the welding notch is provided through the shaping part.

7. The battery tab welding equipment according to claim 6, characterized in that, The shaping part has a shaping plane on the side facing the welding support; The welding support is provided with a welding plane, the shaping plane is parallel to the welding plane, the welding plane is provided with a clearance groove, and the welding notch and the clearance groove are longitudinally corresponding.

8. The battery tab welding equipment according to claim 7, characterized in that, At least one vent hole is provided on the side wall of the welding support, and the vent hole is connected to the clearance groove.

9. The battery tab welding equipment according to claim 1, characterized in that, The laser beam has a single-mode annular spot, which includes an inner spot and an annular spot surrounding the inner spot.

10. The battery tab welding equipment according to claim 2, characterized in that, The battery support is provided with a first limiting block and a second limiting block, which are used to limit the winding core on the battery support.

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