Effective Suppression of the Polysulfide Shuttle Effect in Lithium-Sulfur Batteries by Implementing rGO-PEDOT:PSS-Coated Separators via Air-Controlled Electrospray

Abstract

Lithium-sulfur (Li-S) batteries have been earning significant attention because of their high energy density and cost efficiency. Albeit these outstanding qualities, the polysulfide shuttling effect and low electrical conductivity of the sulfur active material in this battery chemistry results in poor cycling performance. In an attempt to overcome these problems, a hybrid structure of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and reduced graphene oxide was developed and coated on the surface of a conventional separator using air-controlled electrospray. Implementing these coated separators in Li-S batteries led to lower polarization and stymied the polysulfide shuttling effect through the combining effects of electrostatic, physical, and chemical interactions. Our results reveal that the capacity and rate capacity are drastically improved via coating the separator, leading to more than twice the capacity of over 800 mA h g-1 after 100 cycles at 0.5 C rate, when it is compared to those with the pristine separator. Overall, this hybrid coating material shows great promise in enhancing the current Li-S battery technology.