Design and Characterization of Novel sulfur host materials for Lithium/sulfur batteries

Lithium-sulfur (Li-S) battery due to its high theoretical capacity and energy density is considered a promising candidate for the next generation of Li batteries. Nevertheless, the practical application of this system is hindered by several challenges such as low electronic conductivity, volume change, and polysulfides shuttle effect. The work carried out in this thesis focused on the sulfur electrode, with the synthesis and performance evaluation of different sulfur host structures. The performance of these structures was evaluated in terms of sulfur utilization, electrochemical reaction kinetics and capacity retention. The catalytic properties of different class of materials iron, cobalt single atoms, and binary Vanadium manganese oxide structures were evaluated. Absorption properties, morphology and pore structure of the carbonaceous host structure, amount of electrolyte and sulfur loading are key parameters that were evaluated during this work. Indeed, the development of a host material allowing to obtain high performance for low electrolyte amount is an important step towards the commercialization of Li-S batteries. (author)