Single and multilayer composite electrolytes for enhanced Li-ion conductivity with restricted polysulfide diffusion for lithium-sulfur battery

Lithiumesulfur battery is a promising energy source to achieve high energy density at low cost, but its commercialization has been being impeded by a few huddles associated with Li dendrite growth, polysulfide shuttle, and flammability, due to the utilization of liquid electrolytes. In this study, the single- and multi layered flexible composite electrolytes comprising organic poly(arylene ether sulfone)-g-poly(ethylene glycol) and inorganic Li6PS5Br nanoparticles are designed. Both composite electrolyte membranes exhibit excellent mechanical flexibility and thermal stability up to 200 degrees C. The single-layer composite electrolyte illustrates high ionic conductivity of 2.4. 10(-3) S/cm because of the self-assembled poly(ethylene glycol) domains accommodating large amount of free charge carriers. Even though the multilayer electrolyte membrane shows slightly lower conductivity of 8.7. 10(-4) S/cm, it provides quite high lithium-ion transference number of 0.81 with self-extinguishing ability and effective suppression of Li dendrite growth and polysulfide diffusion because of the highly selective Li6PS5Br layer. Accordingly, the Li/S cell assembled with multilayer composite electrolyte shows outstanding cyclic stability retaining 99.2% after 100 cycles at 0.1 C-rate. Those results demonstrate the application possibility of the prepared solid electrolytes for high safety and high performance lithiumesulfur battery. (c) 2023 Published by Elsevier Ltd.

Automated summary

In this study, single- and multi-layer flexible composite electrolytes were designed using organic poly(arylene ether sulfone)-g-poly(ethylene glycol) and inorganic Li6PS5Br nanoparticles. Both electrolyte membranes exhibited excellent mechanical flexibility and thermal stability. The multi-layer electrolyte showed high cyclic stability and effective suppression of Li dendrite growth and polysulfide diffusion.