Laser-induced breakdown spectroscopy as a powerful tool for characterization of laser modified composite materials

Abstract

Laser-Induced Breakdown Spectroscopy (LIBS) was applied in order to investigate the elemental composition in laser modified battery materials. In a first approach, thick film electrodes — all incorporating the same active material (lithium nickel manganese cobalt oxide (Li(Ni1/3Mn1/3Co1/3)O2, NMC)) — were manufactured using the tape-casting technique. In a further approach, femtosecond (fs) laser radiation was used for the generation of three dimensional (3D) micro-structures. 3D micro-grids were successfully implemented into thick film electrodes applying a fs-laser wavelength of 515 nm. The electrochemical performance in lithium-ion cells with untreated and laser-modified NMC electrodes was determined by galvanostatic cycling at high charging- and discharging currents. Finally, LIBS was used as a powerful characterization tool in order to investigate the change in lithium distribution after electrochemical cycling at different State-of-Health. Evaluation of lithium distribution will be used to analyze degradation mechanisms and to find the most appropriate 3D electrode architecture. For this purpose, results of electrochemical cycling and LIBS measurements of untreated and laser-structured NMC thick films have to be correlated.