Enabling Operando Neutron Diffraction for Solid-State Battery Studies

Operando diffraction measurements are essential for advancing electrochemical energy storage by providing real-time insight into the reaction mechanisms during cycling. In solid-state batteries, these measurements also provide critical information about the solid electrolyte. This paper presents a homemade electrochemical cell explicitly designed for operando neutron powder diffraction (NPD) studies of solid-state batteries. The cell allows for detailed structural characterization of electrode materials via Rietveld refinement during battery operation, including at elevated temperatures. We demonstrate its capabilities by performing operando NPD measurements on a state-of-the-art solid-state battery consisting of a LiNi 0.5 Mn 0.3 Co 0.2 O 2 positive electrode, a Li 0.5 In counterelectrode, and a Li 6 PS 5 Cl solid electrolyte. The results of the experiment highlighted the effectiveness of this operando NPD cell and provided valuable guidance for further research in this field.