In Operando Transmission X-ray Microscopy Illuminated by Synchrotron Radiation for Li-Ion Batteries

Transmission X-ray microscopy has caught lots of attention in recent years because it can give us information on the physical characteristics of absorption contrast and phase contrast of the various materials within the specimen and explores the interior morphology. Furthermore, transmission X-ray microscopy does not require a vacuum experimental environment, and hence, aqueous samples are feasible. This technology makes it possible to investigate the chemistry and material change during lithiation/delithiation that comes to improve the properties of commercial lithium-ion batteries (LIBs). In this Review, we first discuss current understanding of the electrode architecture before and after lithiation/delithiation of LIBs and the present bottleneck in material analysis. Then, we move to synchrotron transmission X-ray microscopy, which is the main technology that we wanted to focus on, and highlight recent progress in electrode material investigation. Finally, we discuss the possible opportunities of this technique for further applications to investigate the electrode materials inside of batteries.