Edge-functionalized acetylene black anchoring sulfur for high-performance Li–S batteries

Abstract

To date, most of the research on electrodes for lithium sulfur batteries has been focused on the nanostructured sulfur cathodes and achieves significant success. However, from the viewpoint of manufacturers, the nanostructured sulfur cathodes are not so promising, because of the low volumetric energy density and high cost. In this work, we obtained the low-cost, scalable, eco-friendly mass production of edge-functionalized acetylene black-sulfur (FAB-S) composites by high-energy ball-milling technique for lithium sulfur batteries. The as-prepared FAB-S composite can deliver a high initial discharge capacity of 1304mAh/g and still remain a reversible capacity of 814mAh/g after 200 cycles at a charge-discharge rate of 0.2C in the voltage range of 1.7–2.7V. The observed excellent electrochemical properties demonstrate that the cathodes obtained by the facile high-energy ball-milling method as the cathode for rechargeable Li−S batteries are of great potential because it used the sole conductive additive acetylene black (AB). Such improved properties could be attributed to the partially exfoliation of AB, which not only keeps the AB's inherent advantage, but also increases the specific surface area and forms chemical bonds between carbon and sulfur, resulting in the accumulation of the polysulfides intermediate through both the physical and chemical routes.