Transient interference-based spectroscopy for molecular-bond sensitive probe of lithium ion batttery

Abstract

The lack of effective methods to track in-situ lithium-ion distribution and structural evolution remains a bottleneck in battery industry, while yet no techniques currently allow in-operando dynamic detection of vicious Li2O under realistic conditions. Here, a molecular-bond sensitive probe technique is developed leveraging transient interference-based spectroscopy (TIBS).By creating structured plasma channels through nonlinear interference of multiple femtosecond laser filaments, we achieve extreme spatial confinement of laser pulses, enabling peak intensities above 10 14 W/cm 2 . This field directly ruptures molecular bonds through tunneling ionization and triggers Coulomb explosion, disintegrating materials into constituent elements and fragments while preserving molecular signature information. The resulting element-specific emissions provide intrinsic probes of the original chemical states and local environments. When coupled with machine learning algorithms, this technique enables precise identification of lithium concentration changes as low as 0.3%, making it particularly valuable for in-operando monitoring of atomic scale structural changes and distinguishing Li2O side product from active materials.