Direct Laser Interference Patterning (DLIP) is a laser texturing technique that can be are used to tailor the surface property of a wide range of materials with great speed [1]. The process can modify the topography on a micro/nano scale giving it new or enhanced functions [2]. In this work, the current collectors’ electro-mechanical properties are improved to develop thick film (3D) high power and energy electrodes of Li-ion Battery (LIB). This novel Li-ion cell architecture requires an improved layer adhesion to counter-act the mechanical stress that occurs at the electrode interface during production, drying and electrolyte cycling, diffusion overstress at high charge/discharge rates and during Li-ion insertion/extraction processes. DLIP can increase the interface stability by providing anchoring structures that improve the adhesion strength and additionally improve the electrical property (contact resistance, impedance).

In an effort to bring this technology faster to market and simplify the production, a combination of recent technologies are combined to upscale the DLIP texturing at high-speed in a continuous roll to roll process. For this purpose, an optimized high power ultra-short pulsed laser source is employed. The beam is shaped with a diffractive line top hat and DLIP optical system. The current collectors are scanned using a galvano-scanner in a mark on the fly process on an in-house developed roll-to-roll machine. A pattern of line –like features with a spatial period of 15μm were created using the 220W IR (1064 nm) Edge-wave picosecond laser source. With a repetition frequency of 250 kHz and a pulse energy of 0.9 mJ, the pulse distance was varied from 60 μm to 120 μm to form microstructures with a peak to valley height between 2-3 μm. The textured current collectors are covered with a composite electro (graphite-silicon) and show an improvement of the electro-mechanical performances.

[1] Lang, V., Voisiat, B., & Lasagni, A. F. (2019). High throughput direct laser interference patterning of

aluminum for fabrication of super hydrophobic surfaces. Materials, 12(9). https://doi.org/10.3390/ma12091484

[2] Kunze, T., & Lasagni, A. F. (2017). Direct laser interference patterning : from fundamentals to industrial

applications.