Spectromicroscopic analysis of lithium intercalation in spinel LiMn 2O4 for lithium-ion battery by 3D nano-ESCA

Abstract

The process of lithium-intercalation in spinel-structured lithium manganese oxide (LiMn2O4) particles was probed by a highly spatially resolved X-ray photoelectron microscopy technique using our "3D nano-ESCA" (three-dimensional nanoscale electron spectroscopy for chemical analysis) equipment. We found the change of the line shape in Li 1s-Mn 3p core-level spectra with lithiation/delithiation of the sample. Moreover, we have succeeded in detecting the photoelectron intensity mapping of chemically lithiated/delithiated Li1±δMn2O4 crystals. It suggests the homogeneous intercalation/deintercalation from the crystal surfaces instead of the crystal edges, and the particle size dependence of the intercalation tendency.