(592b) Effect of Thickness and Dopant on the Electrochemical Performance of Li3PS4 thin Glass Electrolyte for Solid State Lithium Sulfur Batteries

One of the most promising beyond-Lithium ion technologies is solid state lithium sulfur battery. However, the technical barriers are low ionic conductivity of solid state electrolyte and high interfacial resistance. An amelioration of the room temperature ionic conductivity of Li₃PS₄ glass electrolyte was achieved through thickness reduction and high valency metal doping. These thin ceramic electrolytic films have been found to possess a crystalline structure that enhances ionic hoping of lithium through a lowering of the activation energy and minimizing the hopping distance. Furthermore, doping the Li₃PS₄ electrolyte with high valency vanadium to form Li₃V₃(PS₄)₃ showed an enhancement of ionic transfer which is attributed to a widening of the ionic conductive channels. These thin electrolyte films were grown on top of lithium metal electrodes via dropwise as well as electrophoretic deposition methods to gauge the efficacy of both techniques in growing defect free films with minimal interfacial impedance. We found that lithium sulfur cells fabricated using thin Li₃PS₄ and Li₃V₃(PS₄)₃ membranes exhibited high specific capacity and long cycle life demonstrating the aptness of the fabricated film to work as solid electrolyte for the lithium sulfur system.