New welding techniques and laser sources for battery welding

New processes and lasers are required to optimize and improve processes for laser welding of batteries. Highly reflective materials cause problems due to lack of absorption, stability, spatter and brittle intermetallic phases. We present solutions for battery welding using pulsed green lasers and nanosecond pulsed IR lasers. Green laser improved process stability and spatter formation between 0.1-0.8 mm penetration depth could be avoided. Nanosecond welding process differs from normal keyhole welding and formation of intermetallic phases can be suppressed. Analysis is based on highspeed camera measurements and metallurgical studies, showing significant improvement in the process and weld quality.