Missions

The growing awareness of the need to adopt cleaner energy storage systems, and the limitations in resources for utilizing Li-ion batteries (LIBs) in several energy storage sectors, has accelerated the development of Na-ion battery (NIB) technology that has entered the marketplace and can be found in power tools with some ingresses in the field of transportation. However, drastic improvements are needed in terms of autonomy for the technology to fully compete with Li-ion LFP. Various strategies, consisting either of using sodium alloys as the negative electrode or assembling a sodium-ion cell without an anode, are currently being studied. Here, we propose moving away from liquid electrolytes and exploring sodium-based solid-state batteries in order to first minimize problems related to sodium dendrites and then develop sodium batteries without an anode. Two approaches will be considered. The first one will consist in identifying suitable positive Na-based electrodes and electrolytes in terms of chemical stability by getting inspiration from the NaCrO2/Na-based halides-hydrides/ Halo/NaxSn battery chemistry already reportedto deviate from liquid electrolyte and explore Na-based solid state batteries to first minimize Na dendrite issues and then realize anode-free Na batteries. Two strategies will be used growth. The first will consist of identifying suitable sodium-based positive electrodes and electrolytes in terms of chemical stability, drawing inspiration from the chemistry of NaCrO2/sodium-based halide-hydride/Halo/NaxSn batteries already reported. The second one will target the development of quasi-solid state battery via insitu polymerization means. Candidates must have in-depth knowledge in the fields of electrochemistry, materials science, and polymer chemistry, as well as a perfect command of English.

Activités

The study will focus on synthesis of electrode and electrolytes for sodium all solid state batteries. The interface chemistry and its stability will be followed by electrochemical and spectroscopic techniques, such as, cyclic voltammetry (both on oxidation, reduction), galvanostatic cycling, change in resistance upon cycling, XPS, XAS etc. Pressure changes and gaseous product evolutions during interface formation and upon cycling will be followed by pressure analyses and mass spectrometry. A multi-disciplinary profile with notions of materials science and electrochemistry would be welcome.

Compétences

Resarcher with 3 or more years of research experience in the Li/ Na-ion battery field is required. Candidates with phd will be preferred. A multi-disciplinary profile with notions of materials science and electrochemistry would be welcome as well as fluency in English.

Contexte de travail

Majority of the work will be carried out in Chimie du solide et énergie at Collège de France, Paris. Few travels to other laboratories in RS2E network is expected based on the requirement.

Contraintes et risques

N/A