Fundamental considerations for lab-based and synchrotron X-ray absorption imaging of electrochemical devices

X-ray absorption imaging, including radiography and computed tomography, is a widely used non-destructive technique to study the morphology of electrochemical device materials and to investigate the transport phenomena within. The goal of this tutorial review is to equip researchers in the field of electrochemistry and beyond with a fundamental and practical understanding of X-ray absorption imaging. First, this tutorial review introduces the principles of X-ray absorption imaging. Then, with a focus on porous electrodes and laboratory-based X-ray systems, the effect of various imaging parameters on the resulting image quality are presented. Typical artifacts observed in X-ray imaging are shown, and methods to resolve them are provided. Furthermore, image processing techniques and common morphological metrics used to describe porous electrodes are reviewed. Finally, considerations specific to synchrotron-based X-ray imaging are discussed, with an emphasis on time-resolved imaging.