Long–cycling lithium–sulfur battery enabled by acrylic modified epoxy soybean oil UV–curing binder

Abstract

Lithium–sulfur (Li–S) batteries are considered as the next generation of excellent energy storage systems due to their high energy density (2,600 Wh kg−1), excellent theoretical capacity (1,675 mAh/g), and the environmental friendliness of sulfur. However, the shuttle effect and the volume expansion have been hindered the development of Li–S batteries. Binders serve as an efficacious way to mitigate the shuttle effect and volume expansion. Herein, we prepared an epoxy soybean oil–based UV–curable binder (AESO) that can improve the long–cycling stability of the Li–S batteries. And the AESO binder can effectively anchor polysulfides through physical confinement and reduce volume expansion by the 3D network structure and polar groups. Therefore, the Li–S batteries assembled with the AESO binder (AESO@S) demonstrated superior electrochemical performance, especially long–cycling performance (the initial discharge–specific capacity of 958 mAh/g, 426 mAh/g after 800 charge/discharge cycles, with a capacity decrease of 0.069 % per cycle).The outstanding properties indicate the possibility of using the epoxidized soybean oil–based UV–curing material as a binder for Li–S batteries, which is a reference value for the development of environmentally friendly and efficient new UV–curing based binders