Three-in-one LaNiO3 functionalized separator boosting electrochemical stability and redox kinetics for high-performance Li-S battery

Abstract

The lithium-sulfur (Li-S) battery, as one of the energy storage devices, has been in the limelight due to its high theoretical energy density. However, the poor redox kinetics and the “shuttle effect” of polysulfides severely restrict the use of Li-S batteries in practical applications. Herein, a novel bimetallic LaNiO3 functional material with high electrical conductivity and catalytic property is prepared to act as a high-efficiency polysulfide shuttling stopper. The three LaNiO3 samples with different physical/chemical characteristics are obtained by controlling the calcination temperature. In conjunction with the high electrical conductivity and excellent catalytic properties of the as-prepared materials, the appropriate chemisorption toward polysulfides offers great potential to enhance electrochemical stability for high-performance Li-S batteries. Particularly, the Li-S cell with the separator modified by such functional material gives a specific capacity of 658 mA h g−1 after 500 cycles at a high current density of 2 C. Even with high sulfur loading of 6.05 mg cm−2, the Li-S battery still exhibits an areal specific capacity of 2.81 mA h cm−2 after 150 cycles. This work paves a new avenue for the rational design of materials for separator modification in high-performance Li-S batteries.