Thesis

All solid-state lithium batteries based on Pyrochlore solid electrolyte

Physical chemistry and electrochemistry
Electrochemical energy storage incl. batteries for energy transition
Due to the increasing energy demand, developing efficient storage systems, both stationary and portable, is crucial. Among these, lithium-ion batteries stand out as the most advanced, capable of being manufactured using liquid or solid electrolytes. All-solid-state batteries have a bright future thanks to their non-flammable electrolytes and their ability to use metallic lithium to increase energy density. Although research on these batteries is dynamic, their commercialization is not yet a reality. Indeed, two significant obstacles to their development remain: the low intrinsic ionic conductivity of solids and the difficulty of obtaining good solid/solid interfaces within the composite electrodes and the complete system.

This thesis explores the potential of pyrochlore oxyfluoride as a new class of superionic material for all-solid-state batteries, which are more stable in air and have higher ionic conductivity than current solid oxide electrolytes. The electrochemical properties of all-solid-state batteries will be carefully examined using a combination of in situ and operando techniques, such as XRD, Raman, ion beam/synchrotron analysis, solid-state NMR, X-ray tomography, etc.

Keywords :
Solid electrolyte, All-solid battery, Nuclear magnetic resonance, Electrochemistry, Pyrochlore Oxyfluoride, in situ/operando, Spectroscopy, Synchrotron
SL-DRF-25-0442
master (ou équivalent) en science des matériaux
October 1 2025
Paris-Saclay
Sciences Chimiques: Molécules, Matériaux, Instrumentation et Biosystèmes (2MIB)
Saclay
CEA
Direction de la Recherche Fondamentale
Institut rayonnement et matière de Saclay
Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l’Energie
Laboratoire d’étude des éléments légers
CEA
CEA