Unique starch polymer electrolyte for high capacity all-solid-state lithium sulfur battery

Abstract

Solid polymer electrolyte (SPE)-based lithium sulfur battery offers high energy and safety for new energy vehicles and storage. However, the low room temperature ionic conductivity of the existing SPE limits the battery performance. Herein, a novel SPE film using food grade starch as a host was fabricated. This electrolyte provides exceptional lithium ion transportability with an ionic conductivity of 3.39 × 10⁻⁴ S cm⁻¹ and lithium ion transference number of 0.80 at 25 °C. The application potential of this starch hosted electrolyte was demonstrated by all-solid-state lithium sulfur battery systems presenting the initial discharge capacity of 1442 mA h g⁻¹, an average discharge capacity of 864 ± 16 mA h g⁻¹ at 0.1 C for 100 cycles, 562 ± 118 mA h g⁻¹ at 0.5 C for 1000 cycles at room temperature, and 388 ± 138 mA h g⁻¹ for 2000 cycles at 2 C and 45 °C. This opens a bright route towards realizing energy power and safety with low cost and high sustainability.