Amphiphilic Surface Modification of Hollow Carbon Nanofibers for Improved Cycle Life of Lithium Sulfur Batteries

Tremendous effort has been put into developing viable lithium sulfur batteries, due to their high specific energy and relatively low cost. Despite recent progress in addressing the various problems of sulfur cathodes, lithium sulfur batteries still exhibit significant capacity decay over cycling. Herein, we identify a new capacity fading mechanism of the sulfur cathodes, relating to Li(x)S detachment from the carbon surface during the discharge process. This observation is confirmed by ex-situ transmission electron microscopy study and first-principles calculations. We demonstrate that this capacity fading mechanism can be overcome by introducing amphiphilic polymers to modify the carbon surface, rendering…