Synthesis and electrochemical performance Assessment of sunflower oil-based organosulfur Co-Polymers as the cathode additive for Li-S battery

Abstract

Lithium-Sulfur battery (Li-S) is considered as a promising new generation battery chemistry. Nevertheless, the sulfur based battery chemistry has downsides in terms of the low electronic conductivity, polysulfide shuttle effect, and low active material utilization. Currently, there are several strategies available to suppress LiPS shuttling and thereby enhance cycle life behavior of the Li-S battery. However, there is no existing literature on the use of organosulfur-based copolymer as a cathode additive material in Li-S. Herein, we have investigated the feasibility of organosulfur copolymer synthesized using sulfur, fresh and used cooking (sunflower) oil. The developed polymers were used cathode additives. The results reveal that the copolymer developed by used cooking oil-loaded cathode (poly-S-UCO@SC) delivers high specific discharge capacity of 936mAh/g at 0.05C-rate and the copolymer developed by fresh sunflower oil loaded cathode (poly-S-SF@SC) exhibits 828mAh/g. However, the poly-S-UCO@SC exhibited poor structural stability, continuous cathode degradation and poor electrochemical performances than poly-S-SF@SC. The poly-S-SF@SC showed improved polysulfide conversion, reduced shuttle effect, reversible redox process, 66.5 % capacity retention for 40 cycles with stable cycling stability and shows much potential as a suitable cathode additive material compared to poly-S-UCO. The results demonstrate that utilization of biomass-based components in Li-S batteries may trigger new research pathways in Li-Sulfur battery science and technology.