CNRS researcher (CR) in MATRMAG team

My research focuses on a better understanding of the limitations of devices for electrochemical energy storage, such as lithium-ion batteries and supercapacitors. The first step is to study the materials with ex situ Nuclear Magnetic Resonance (NMR) spectroscopy. The electrochemical device is stopped at a given state of charge, the different constituants are taken apart in an Argon glovebox and transfered into rotors for magic angle spinning NMR. This approach gives excellent resolution and detailed information on the materials but metastable states and transient phenomena are often missed.

A complementary approach is in situ NMR, for which the NMR measurement is performed on the full electrochemical device while it is charged and discharged. The main issue in this case is the overlap of the signals coming from all the components in the cell: lithiated electrodes, lithium-containing electrolyte. We developped an approach that mixes spectroscopy and imaging (MRI) to overcome this issue.