A polymer enhanced sulfur/graphene aerogel as a no-slurry cathode for lithium-sulfur batteries

Abstract

Due to their unique and promising microstructures, sulfur/graphene aerogel composites have become more appealing for research interests than pristine carbon materials to improve the electrochemical performances of cathodes in lithium-sulfur batteries. Herein, we presented a facile no-slurry method to synthesize a three-dimensional polyvinylpyrrolidone-sulfur/graphene aerogel composite, which can be pressed into flexible sheets and directly used as a cathode without any additives. With a superior microstructure and high electrical conductivity, the as prepared cathode enables a high areal sulfur loading of 2.8 mg cm-2, which delivers an initial gravimetric specific capacity of 1192.6 mA h g-1 and an areal specific capacity of 3.34 mA h cm-2 at 0.1C. After the first few cycles and stabilization, the cathode exhibits an excellent capacity retention of 94.6% from the 10th to 50th cycle, together with a great rate capability and cycling stability for 200 cycles at 0.5C. Moreover, this no-slurry method is convenient to be integrated with other composites, which has the potential to further improve the performances of lithium-sulfur batteries and simplify the preparation process.