Rational Design of Cathode Materials for High Performance Lithium-Sulfur Batteries

Abstract

Sulfur, one of most promising cathode candidates for next-generation lithium ion batteries, shows a limited cycling performance due to its shuttling effect, low conductivity, self-discharge and volume expansion during lithiation and delithiation process. According to the operation principles, failure mechanism, and recent progress on lithium-sulfur batteries, here we developed several scalable and rational synthesis methods for high performance cathode materials. We dissolved commercial sulfur to anhydrous ethylenediamine (EDA) to form an EDA-S precursor, and then we reduced the sulfur particles size at conductive carbon black substrate. The 70% theoretical capacity of sulfur cathode battery was obtained. We also melted commercial sulfur into conductive carbon black matrix, the nanosponge carbon sulfur composite was successfully synthesized. Characterization techniques (XRD, SEM, TEM) were used to check the structure and morphology of the received materials. Coin cell battery cyclic voltammetry (CV) and cycling performance were used for electrochemical measurements.