A Novel Approach of Sea Urchin-like Fe-Doped Co3O4 Microspheres for Li-S Battery Enables High Energy Density and Long-Lasting.

Abstract

The poor cycle stability caused by the shuttle effect of polysulfides which have been key scientific issue in the development of high-efficiency lithium-sulfur (Li-S) batteries. In this work, the authors report a Fe-doped Co3O4 (named FCO) that was used as a sulfur-loaded host material for Li-S batteries. We demonstrate the important roles of well-designed Co3O4 particles and Fe atoms in regulating polysulfide conversion due to the strong adsorption of polysulfides by polar Co3O4, whereas Fe atoms and Co3O4 catalyze polysulfide conversion. Therefore, the LiS batteries with FCO-180 (When the hydrothermal temperature is 180 °C) sea urchinlike composites exhibited a high superior energy density (992.7 mAh g-1 at 0.2 C, after 100 cycles) and long-term cyclability (649.4 mAh g-1 at 1 C, 300 cycles) with high sulfur loading (75 wt%). This work confirms that the FCO-180 sea urchinlike increases not only the capacity of high-rate but also a generic and feasible strategy to construct practical Li-S batteries for emerging energy-storage applications.