Surface imaging by ABF-STEM: Lithium ions in diffusion channel of LIB electrode materials

Abstract

Lithium ions in LiMn2O4 crystals have been shown observable by using an aberration corrected electron microscope (R005) which has achieved a sub-50 pm resolution. Based on the annular bright-field image of the observed image, surface imaging of a LiMn2O4 crystal is discussed through simulation. The present simulation showed that ABF images with large convergence angles are sensitive to the top surface profile. A vacancy locating at the top surface of the lithium or manganese atomic columns can be observable with contrast reduced by 10-25% from the columns without vacancy. © 2012 The Surface Science Society of Japan.