Product Code: ICAL06_1302

High Speed Fiber Laser Welding for Fuel Cell Components
Authors:
Stanley Ream, EWI; Columbus OH USA
Presented at ICALEO 2006

As energy independence becomes a more pressing concern in the U.S. and other countries, industry and government fuel cell development efforts have gained momentum. There are several leading fuel cell types and hundreds of specific fuel cell designs. Yet, despite the design diversity, there is a common theme that appears in many systems, specifically the need to join, seal, and/or weld thin, stainless steel components at very high production rates. Fuel cell system components such as bi-polar plates, fuel processors, recuperators, and heat exchangers are all comprised of dozens or hundreds of thin, stamped components that require very high speed assembly. Laser welding for these thin (100-200 um) stainless steel sheet metals has emerged as a leading candidate for fuel cell component assembly, but production rates and welding costs remain large obstacles. EWI has been addressing these challenges through the development of very high speed laser welding technology, using a 600 watt, single-mode, fiber laser. Laser lap welding travel speeds in excess of 100 meters per minute have been achieved, while gap tolerances and "humping" behaviors are still under investigation. In this presentation EWI will describe its most recent progress in establishing new limits for high speed laser welding of thin sheet metals.