Flexible CNT/S-GO composite film without current collector for high-energy density lithium-sulfur batteries

Abstract

Lithium-sulfur batteries are well-known for their higher theoretical energy density, low cost, and environmental friendliness, making them an ideal next-generation energy battery to replace conventional lithium batteries. Here we introduce an easy-to-form composite flexible film of CNT/S-GO with no current collector. The composite film is fabricated by a simple process that is coating slurry on the surface of hydrophobic sapphire. This composite film exhibits excellent flexibility; the electrochemical measurement results show that the modified membrane exhibits an initial discharge specific capacity of 1050 mAh·g−1 at 0.1 C. In addition, at 0.5 C, the specific capacity remains around 800 mAh·g−1, and after 200 cycles, the capacity retention rate is 82.4%. The flexible battery based on the flexible cathode shows well mechanical and electrochemical performance in the folded state, and the electrode exhibits well cycling performance, which highlights the practical application of our carefully designed electrode in the flexible power system. In this paper, a cheap and simple method for high-energy flexible lithium-sulfur batteries has been provided.