The current rapid growth of the e-mobility sector is driving demand and innovation in the manufacture of batteries. This is particularly evident in the development of laser-based


processes for the manufacture of Li-ion battery cells. There is a great diversity in mechanical designs and in the chemistries used, but all comprise of thin foil anode and cathodes that need to be cut to shape. Traditionally this has been done using mechanical processes such as slitting and stamping, but recent increases in laser powers and a competitive marketplace have made lasers for cutting more appealing, both technically and commercially, to a point where they are now considered the process of choice.





The variety and complexity of battery foil materials, as well as the electrode designs, make it challenging to identify the most appropriate laser technology. Requirements range from the relatively simple slitting or notching of thin bare metal foils to the complex profiling of complete electrodes, where both bare foil and coated material need to be cut in a single process.





The materials break into anodes (copper foil coated with graphite or graphite/silicon) and anodes (aluminum foil coated with active Li+ containing mediums such as NMC or LFP). As with many other laser applications cost and productivity are the prime drivers in this competitive market, but this is underpinned by a strong focus on cut edge quality. Cutting


defects such as burrs can lead to the risk of short circuit leading to catastrophic failure of the battery cells, so need to be minimized. But as ever manufacturers require highest possible processing speeds with the highest possible edge quality which is challenging.





This contribution gives a broad overview of the challenges of laser cutting of battery foils and explores the pros and cons of cw vs ns vs ps for a variety of different materials. The analysis focuses on achievable processing speeds as well as cut edge quality and looks at the influence of various laser parameters as well as spot size, working fields and processing strategies which are also discussed. This work reveals that the choices are not always straight forward, and users are left to balance the need between


COST – QUALITY – PRODUCTIVITY.