Exploring How The Carbon-Sulfur Cathode'S Properties In A Lithium-Sulfur Battery System Affect The Cell'S Performance

Abstract

Lithium-sulfur batteries have drawn a lot of attentions due to the high theoretical discharge capacity (1675 mAh/g), natural abundance of sulfur and environmental friendliness. However, elemental sulfur is basically an insulator, resulting in extremely low electrical conductivity. In addition, the highly soluble polysulfides formed during charge and discharge tend to pass through the separator to the lithium anode and form lithium polysulfide, resulting in electrochemical irreversibility and thus poor cyclability. Hierarchical porous carbons were proposed to improve the cyclability by exploring the porous structure to sequester the sulfur. Ice-templating has been shown to successfully synthesize hierarchical porous carbons but their electrical conductivity had not been optimized. In this work, hierarchical porous carbons with improved electrical conductivity were developed by carbonizing the porous carbons at different temperatures and using catalytic graphitization method and their performance as electrodes was evaluated.