High power ultrafast laser processing of electrodes: Up-scaling in roll-to-roll environment

The introduction of laser-generated 3D capillary structures in electrodes of Li-ion cells enables a more homogenized electrolyte wetting, which helps avoiding warm aging and shortens cell storage time prior and after electrochemical formation. In this study, the roll-to-roll (R2R) laser patterning of graphite anode material with a high-power ultrafast laser source was investigated. The governing parameters of laser structuring and their impact on active mass loss, electrode architecture, and electrolyte wetting behavior were analyzed. The trade-off between the quality of the structures and the processing times for an optimized R2R-processing was assessed. The application of a diffractive beam-splitter was evaluated.