In a view to develop electric vehicles, researches on lithium batteries are now focusing on sulfur active material. Indeed, this new system should allow to produce cheap and high energy batteries of about 600 Wh/kg. While being developed for more than 40 years, the limitations of such a system are still quite problematic: elemental sulfur is an electronic insulator, sulfur and intermediate lithium polysulfides are soluble in the electrolyte and final discharge product Li2S is non-soluble and insulating too.
This post-doctoral position will thus aim at improving the performances of the sulfur positive electrode, by combining :
- Carbon nanotubes that will allow to improve the electronic conductivity of the positive electrode, as well as to provide a substrate for sulfur grafting
- Disulfide functions that will be grafted on the nanotubes. Thanks to this chemical grafting of active material, the electrochemical reaction would occur without leading to sulfur and polysulfides dissolution, thus leading to higher capacity and cyclability along with lower self-discharge.