Blue high-power laser sources for processing solutions in e-mobility and beyond

Abstract

The laser based processing of copper components with blue lasers with 450nm wavelength gained significance in the last years due to the increasing demand in eMobility applications. The high absorption level allows new process approaches, which were formerly however restricted by the limited power level of blue laser systems. With the availability of multi-kilowatt blue laser systems with 450 nm wavelength, a further step has been achieved to extend the application range for copper components. Process stages from heat conduction welding to keyhole welding can be precisely adjusted. The properties of these process stages however vary from the conventional behavior known from IR laser sources. In this contribution, the properties and differences compared to IR sources are investigated. This is achieved by an evaluation of the process stages by high speed videography and an investigation of the process robustness e.g. gap bridgeability in the example of battery applications. Furthermore, we will review the latest application results regarding blue laser welding for the battery cell manufacturing and the battery module interconnection. This consists of welding results of copper to copper connections and also dissimilar material combinations.