Composite Solid-State Sulphur based electrolyte for Lithium-Sulphur system

Abstract

In the present spectrum, the world requires a new generation of energy storage systems with high energy density, lightweight, durability and low cost. The liquid electrolyte currently being used in batteries have safety concerns as these are highly volatile and flammable; loss of active material causes a reduction in discharge capacity and short-circuiting due to dendrite formation. For some time now, solid-state batteries have garnered much attention, given their ability to exhibit high safety, high energy density and better cycling efficiency. But the success of these batteries has been hindered by the low ionic conductivity and poor transfer of ions across electrolyte and electrode interface. To improve these properties, a composite solid electrolyte is synthesised. The ceramic electrolyte provides the system with high conductivity and thermal stability; the polymer matrix improves the interfacial properties for better transfer kinetics. In this work, we have fabricated a CSE with Li6PS5Cl electrolyte dispersed in a PVDF matrix. The pristine electrolyte offered an ionic conductivity of 1.227 X 10-4 S/cm. The cell testing gives a 1st discharge capacity of 436.3 mAh/g. This finding opens up the possibility of making high-capacity solid state batteries for the Lithium-Sulphur system.