Energy storage materials are a topic of continued interest, particularly with regards to elucidating structure-property relationships. This includes not only exploratory work in terms of mapping complex ternary or quaternary phase diagrams but understanding material performance in assembled test cells and devices. X-ray diffraction (XRD) is one of the key analytical techniques used in these studies, providing not only information regarding the unit cell (e.g., expansion or contraction) but also microstructural information that can be attributed to processing or synthetic conditions. The study of electrochemical devices under operating conditions, or in operando, provides access to considerably more information, such as reversibility of phase transitions, development of undesirable secondary phases, and grain growth as a function of cycling.

In this presentation, we discuss instrument geometries and newly developed devices for in operando studies of battery materials. In particular, we highlight a battery cell that can be operated in both reflection and transmission geometries. Diffractometer components will also be discussed, including topics such as beam optics, detector technologies, and integration of potentiostat controls for charge/discharge applications.