Laser cutting of silicon anode for lithium-ion batteries

Lithium-ion batteries (LIBs) are vital in the transportation sector due to their promising technology meeting the future hybrid and electric vehicles requirements. The limited capacities of anode and cathode materials are the obstacle in the current state of LIBs to obtain good performance. Silicon (Si) has the highest capacity compared to the currently used graphite anode. In this study, laser technology was employed to perform cutting of silicon anodes, which previously have not been studied. First, the optical properties of silicon anode are measured, and four types of cutting widths such as top, kerf, clearance, and burr as well as five types of physical cutting phenomena such as excessive fill cutting, proper full cutting, partial cutting, partial melting of the current collector and full ablation of active material were defined and measured. Minimum average cutting power, as well as cutting and energy efficiencies, are established for all parameter groups. The effects of process parameters on the measured cutting widths are studied by developing mathematical models using multivariate regression based on the response surface method (RSM). The process parameters contribution was also analyzed using the analysis of variance (ANOVA). For the formation of kerf width, clearance width, and burr width the cutting speed have the largest contribution with percentages of 53, 55, and 67 respectively. The laser power also has a 65% impact on the formation of the top width.