Descriptif des activités de rechercheNa-ion batteries (NIBs) have recently been developed as an alternate for future sustainable energy storage system in place of the conventional Li-ion batteries (LIBs). Among those which have lately been studied as positive electrode materials for NIBs, Na3V2(PO4)2F3 (NVPF) is the most promising one due to its highly stable poly-anionic framework, and its high theoretical energy density of 507 Wh.kg-1 (128 Ah.kg-1 at an average potential of 3.95 V vs. Na+/Na). Despite the presence of three Na+ per formula unit, only two of which are electroactive. The aim of this PhD work is to enhance the performance and the capacity of the NVPF-structured materials through the extraction of the third Na+ by a cationic / anionic substitution in the host structure. The crystal structure of the obtained materials will be elucidated by a combination of capillary powder X-ray diffraction, neutron diffraction and synchrotron diffraction techniques. Furthermore, the changes in the local environment of the interest ions will be detected by the use of solid-state NMR, which is done in collaboration with Dr. Dany CARLIER (ICMCB, Bordeaux), infrared and X-ray absorption technique. Finally, the electrochemical testing will help to confirm the improvement in the electrochemical performance of the substituted compounds.
- PhD (on-going / 2016 – 2019): Dr. Laurence CROGUENNEC (ICMCB, Bordeaux) and Prof. Christian MASQUELIER (LRCS, Amiens).
New poly-anionic materials for positive electrode in Na-ion batteries.
- Erasmus Mundus M.E.S.C Master (Materials for Energy Storage and Conversion), 2014 – 2016.
S1: Aix-Marseille Université (FR), S2: Warsaw University of Technology (PL), S3: Université de Picardie Jules Verne (FR).
Master thesis: Synthesis and solid-state NMR characterisation of NASICON-structured materials applied in all solid-state Li/Na-ion batteries (University of Cambridge, UK). Supervised by: Dr. Oliver PECHER, Dr. Maria TSIAMTSOURI, and Prof. Clare P. GREY.
Projets en cours
This PhD project is funded by the French research network on electrochemical energy storage (RS2E), 2016 – 2019.