Laser Sealing Technique for Fuel Cell Application

Parameter analysis for laser welding, optical measurement tests and tension shear tests are conducted on materials for fuel cell stack bipolar plates, and seven groups of welding parameters are chosen and tested. The optical measurement tests reveal that at the same power and duration time, specimens 1 (20 PPR, 5 mm/s) and 4 (50 PPR, 10 mm/s) obtained greater welding quality with proper welding frequency and velocity. The tension shear tests demonstrate that the bonding strength of both specimen 1 and 4 exceeded 0.4 MPa, the result of which are proper applied to high power fuel cell systems. A new fuel cell stack structure is subsequently designed for this high strength and accuracy modular sealing technique.