Views: 0 Author: Site Editor Publish Time: 2025-09-23 Origin: Site
The battery pack enclosure, serving as the core of protection, is often made of thin - walled materials such as aluminum alloy and 304 stainless steel (with thickness commonly ranging from 1.0 - 2.5 mm). During welding, it is highly susceptible to deformation such as warping and dents due to uneven heat input and stress concentration, which directly affects the sealability and assembly accuracy. However, deformation can be effectively controlled through proper equipment selection and process optimization.
First and foremost, the right welding equipment must be chosen to reduce heat input from the outset. Traditional spot welders have a large heat - affected zone when performing contact welding, making thin - walled enclosures prone to heat - induced deformation. It is recommended to prioritize laser welders. With high energy density and a small spot size (controllable within 0.2 - 0.5 mm), laser welders have a heat - affected zone that is only 1/3 - 1/5 that of spot welders, significantly reducing the stress caused by uneven heating of the enclosure. For mass production, combining laser welders with robotic systems is even better. The robotic laser welder has a repeat positioning accuracy of ±0.02 mm, ensuring precise weld seam location and preventing local deformation exacerbated by welding deviations.
Next comes the precise control of core process parameters. Welding current/power must be matched with the thickness of the enclosure: for a 1.2 - mm - thick aluminum alloy enclosure, a laser power of 1500W and a welding speed of 1.5 m/min are sufficient. When the thickness increases to 2.0 mm, the power should be adjusted to 2200W and the speed reduced to 0.9 m/min to avoid deformation caused by excess energy. Meanwhile, pulsed welding mode should replace continuous welding. Through the cycle of "pulsed energy + interval cooling," the enclosure is given enough time to dissipate heat and reduce accumulated heat.
The welding sequence and path design are also of great importance. The principle of "symmetrical welding, from the middle to the ends" should be followed: for example, for a rectangular enclosure, weld the diagonal seams first, then the four sides, and each side should be welded in sections from the middle to the ends to allow for even stress release. For enclosures with stiffeners, weld the seams connecting the stiffeners and the shell first to enhance structural rigidity before welding the peripheral seams, reducing the likelihood of deformation.
In addition, auxiliary tooling and subsequent treatment can further control deformation. During welding, use water - cooled tooling fixtures to hold the enclosure in place. The fixture's mating surface should match the shape of the enclosure to quickly remove local heat through cold water circulation. After welding, place the enclosure in an aging furnace for low - temperature annealing (about 120℃ for 2 hours for aluminum alloy) to eliminate residual stress and prevent deformation later on.
To solve the problem of welding deformation of battery pack enclosures, the compatibility of equipment and process is the key. PDKJ's laser welders and robotic laser welders have precise energy control. Combined with customized tooling solutions, they can optimize welding parameters according to the material and thickness of the enclosure, effectively suppress deformation, and ensure welding quality and assembly accuracy.
If you have welding machine requirements, please contact Ms. Zhao
E-Mail: pdkj@gd-pw.com
Phone: +86-13631765713
