Fast cutting of lithium-ion battery electrodes with a high-power ultrashort pulse laser and temporal pulse tailoring

Laser cutting of electrode foils is an important step in lithium-ion (Li-ion) battery manufacturing, with demanding requirements on both throughput and quality. Quality is critical because defective cuts can ultimately lead to safety hazards over the life of the battery and fast cutting is necessary to meet high-volume production demands. With such requirements, high-power Ultrashort Pulse (USP) lasers are a natural choice. In this work, we present results for laser cutting of Li-ion battery anode and cathode electrode materials. The anode is graphite-coated copper foil, and the cathode is aluminum foil coated with NMC. Both electrodes are double-side coated and ~100 µm thick. Using 200 Watts of infrared (IR) femtosecond pulses, high-speed cutting with excellent quality is achieved. With temporal pulse tailoring, speed is increased by up to 65% compared to a single-pulse process. Notably, NMC cathode cutting speed was found to exceed 2.5 m/s while achieving excellent quality.