Direct Observation of Lithium Atoms Using Spherical Aberration Corrected STEM

Abstract

For developement of lithium ion battery, diffusion mechanism of lithium ions in the cathode electrode and at the boudary between the cathode and electolyte has been one of the important issues. Using a 50 pm resolved electron microscope (R005), lithium atomic columns in the materials of spinel structure have been observed in annular bright field (ABF) imaging. In this paper, we will show that the column intensity is proportional to the number of lithium ions in the column and also that the spinel structure is transformed into a defective NaCl-type structure by removing litium ions. In addition, we will describe feature of ABF images.