Hierarchically Porous Carbon Derived from Peanut Shells for High-performance Lithium-sulfur Batteries

Abstract

Lithium-sulfur (Li-S) batteries are considered to be a promising energy storage device because of their high theoretical energy density and relatively low cost. But low rate performance and poor cycle stability arising from the poor electronic conductivity and the shuttling of polysulfide intermediates hamper its practical application. In order to address these shortcomings, hierarchically porous carbon (HPC) derived from peanut shells is employed as a host to accommodate sulfur for the first time. As-prepared HPC possesses a hierarchically porous structure with a relatively high specific surface area of 1775.7 m2 g−1 and a large pore volume of 1.457 cm3 g−1. When as-prepared HPC was employed as cathode hosts for lithium-sulfur batteries, it was found that S/HPC composite displayed an excellent electrochemical performance. The initial discharge capacity of 1659.8 mA h g−1 is reached at 0.5 C and a reversible capacity of 815.7 mA h g−1 can be maintained after 100 cycles. Even if the current density increas...