Marie GUIGNARD is a CNRS researcher with expertise in solid-state chemistry. Her main interest is the structural studies of inorganic materials of different types (oxides vs sulfides, crystalline powders vs glasses, …). Starting from 2010, she has been working on lithium and sodium layered oxides as positive electrode for lithium and sodium-ion batteries. Her interest is mostly focused on understanding the relationships between their composition, their strutcure and their electrochemical performances. More specifically, she has performed operando powder X-ray diffraction and pair distribution function (PDF) experiments to understand structural mechanisms occurring both at the long- and the short-range order in these materials upon cycling. She has been involved in several research collaborations with industrial partners including Toyota Motor Europe, Umicore or SAFT – Total. She has co-authored 43 peer reviewed papers and 4 patents, and she has given 12 invited talks at international conferences about solid state chemistry or batteries.