Because lithium-ion batteries have higher energy density than other secondary batteries, it has been possible to make them smaller and lighter. This has enabled them to spread rapidly as power sources for mobile devices such as laptop computers and cellular phones. The demand for lithium-ion batteries keeps growing relentlessly and, in recent years, the electrification of vehicles using secondary batteries has become a worldwide trend toward realizing a low-carbon society. Furthermore, because conventional liquid-state cells using an organic solvent as the electrolyte are flammable, the development of safe, all-solid-state cells using a solid electrolyte is being actively pursued in Japan and the rest of the world.
In this light, many expect the performance of lithium-ion batteries to improve further, together with longer life and better safety. X-ray diffraction (XRD) is considered one of the effective analytical techniques required to evaluate the improved performance of lithium-ion batteries.
To examine the crystallization and phase ID analysis of synthesized battery materials, lab-scale X-ray diffractometers that are readily available for research are frequently used. On the other hand, operando (or in-situ) measurement of the changes in the crystal structure of the positive and negative electrode materials during the charging and discharging processes are frequently conducted at synchrotron facilities where high-intensity X-rays are available. Recently, operando measurement has become possible even with lab-scale X-ray diffractometers due to improved performance of X-ray sources, optical elements, and detectors. This article introduces examples of characterizing lithium-ion battery materials using SmartLab.