Advanced Electron Microscopy Characterization of Sodium-Ion Battery Materials

Abstract

Electron microscopy is a key characterization tool in the development of battery materials. Standard scanning electron microscopy can be used to reveal complex microstructures, and transmission electron microscopy (TEM) can provide a higher-resolution insight into the microstructures, coupled with information on crystal structure, disorder, and valence states. This chapter focuses on advanced TEM characterization of sodium-ion battery (NIB) materials, including high-resolution scanning TEM, electron energy loss spectroscopy, and in operando TEM. It focuses on developing techniques that have not yet been used in NIBs; this includes cryo-TEM, 4D-scanning TEM, electron holography, and electron tomography. Aberration-corrected TEMs are becoming more commonplace, which further pushes the imaging resolution through correcting for spherical and/or chromatic aberrations in the electron beam. Such powerful tools can be used with standard TEM techniques such as electron diffraction, conventional imaging, energy dispersive X-ray spectroscopy, and electron energy loss spectroscopy.