Mitigating side reaction for high capacity retention in lithium-sulfur batteries

Li-S batteries have shown great potential as secondary energy batteries.However,the side reaction between Li anodes and polysulfides seriously limited their practical application.Herein,the artificial protective film,which is consisted of Li-Nafion and TiO_(2),was designed and successfully prepared to achieve a corrosion-resistant Li anode in Li-S battery.In the composite protective film,the Li-Nafion could efficiently prevent the contact between Li anodes and polysulfides,and the incorporation of TiO_(2)nanoparticles into the Nafion could significantly increase the ionic conductivity and mechanical strength of the protective film.Li-Li symmetric cells with an optimal artificial protective film exhibited an extended cycle-life of 750 h at a current density of 1 mA/cm^(2)in Li_(2)S_(8)electrolyte.Moreover,the Li-S full battery with an optimal protective Li anode exhibited higher capacity retention of 777.4 mAh/g after 100 cycles at 0.1 C as well as better rate performance than the cell with a pure Li anode.This work provides alternative insights to suppress the side reaction for Li-S batteries with high capacity retention.