Hollow spherical Lanthanum oxide coated separator for high electrochemical performance lithium-sulfur batteries

In order to alleviate the shuttle effects of lithium polysulfides (LiPSs) in Lithium sulfur batteries. Lanthanum oxide (La2O3) with a hollow spherical structure was synthesized by a spray dryer and coated on the routine separator evenly as the main coating material to trap LiPSs and accelerate the electrochemical kinetics of the redox reactions. CV tests and EIS analysis demonstrate that Li-S pattery equipped with this modified separator shows higher discharge potential and faster electrochemical reaction in comparison with the routine separator and super P coated separator samples. Charge/discharge measurements at different current densities show that Li-S cell with the hollow spherical La2O3 coated separator can deliver an initial capacity of 966 mA hg(-1) at 1C and maintains a discharge capacity of 720 mA hg(-1) after 200 cycles. Besides, it presents a high discharge capacity of 820 mA hg(-1) at 2C which demonstrates a promising rate performance. (C) 2017 Published by Elsevier Ltd.