The application of fiber laser in tab welding in soft-pack batteries mainly includes tab welding and shell welding.
The tabs of soft-pack batteries are generally made of copper and aluminum, with thicknesses ranging from 0.1 to 0.4mm. Due to the series and parallel connection of different numbers of single cells, there will be several types of welding of the same or dissimilar materials. For the same material, whether it is copper or aluminum, we can perform good welding. However, for copper and aluminum dissimilar materials, brittle compounds will be produced during the welding process, which requires minimizing heat input during the welding process to reduce the production of brittle compounds. At the same time, our welding direction should be from aluminum to copper. In addition, ensure that the tabs are tightly pressed together and between the tabs and the Busbar to ensure that the interlayer gap is within the specified range.
Typical weld pattern: Oscillating wavy line
Common splicing materials and thicknesses:
0.4mm Al + 1.5mm Cu
0.4mm Al + 0.4mm Al + 1.5mm Cu
0.4mm Al + 0.3mm Cu + 1.5mm Cu
0.3mm Cu + 1.5mm Cu
0.3mm Cu + 0.3mm Cu + 1.5mm Cu
Key points to ensure welding quality:
1、Ensure that the gap between the tabs and the busbar is within the specified range；
2、Welding methods should be reduced to reduce the generation of brittle compounds during the welding process；
3、Combination of material types and welding methods.
At present, the shell material is mostly 5+6 series aluminum alloy. In this case, generally used high-power multi-mode laser + high-speed galvo scanner head or swing welding head in laser welding process, in both cases, better welding results can be obtained. If 6 series + 6 series or higher grade aluminum alloys are used for strength and other performance considerations, filler wire welding may be used, but filler wire welding not only requires an expensive wire feeding welding head, but also increases the number of welding wires. This consumable not only increases the cost of production and use, but also increases the cost of consumable management. In this case, we can also try to use a Adjustable Mode Beam Lasers to obtain good welding.
IPG Adjustable Mode Beam (AMB) lasers
|
Battery Shell Material |
Laser Power |
Scanner welding head Model |
Welding Strength |
|
5 series & 6 series aluminum |
4000W or 6000W |
LS30.135.348 |
10000N/80mm |
More details, pls feel free to contact to our sales.
