PowerPhotonic’s paper on laser beam shaping for EV battery welding performance and safety.
01 August 2024
PowerPhotonic’s newly published white paper, ‘Beam Shaping for Enhancing Electric Vehicle Welding Applications’, shows how the company’s freeform, wafer-scale optics can optimise laser welding machine performance and safety in Lithium-ion, electrical vehicle (EV) battery manufacture. Each lithium-ion cell within the EV battery pack has multiple foils of anodes and cathodes that must be precision welded into electrical terminals and a busbar connection. In addition, the batteries are sealed into a protective casing for safety purposes, using laser welds which must be suitably safe, strong and durable during the EV lifecycle. Lithium-ion is highly combustible, so for safety purposes and to avoid risk of ignition, the weld melt-pool, residual spatter and heat overrun must all be contained within the welding process.
Dr. Stephen Kidd, Head of Sales and Marketing at PowerPhotonic, explains, “Huge growth in EV sales and laser welding manufacture are creating high demand for Lithium-Ion battery welding. PowerPhotonic’s beam shaping optics provide a relatively inexpensive modification to laser welding machines. They adjust the intensity and shape of the laser beam profile for optimal laser welding performance. The weld melt-pool size and thermodynamics are critical - shaping the beam to heat the material pre- and post-weld adjusts the solidification physics reducing brittleness, air pockets and cracks. The weld spot size and penetration depth can also be adjusted for aesthetics and strength, with ‘ring and core’ type profiles shown to reduce spatter and improve EV battery manufacture safety.
“PowerPhotonic uses fused silica for its freeform welding optics. The finished optics are exceptionally smooth with low scatter and absorption, making them ideal for high-power applications like laser welding. By contrast, most existing welding optics are rotationally symmetric, limiting weld profile and intensity adjustments.”
PowerPhotonic’s white paper clearly demonstrates how beam shaping offers significant laser welding performance and safety enhancements for EV battery manufacturers.