Free-standing sulfur cathodes composited with carbon nanorods arrays for Li-S batteries application

• Construct carbon nanorods arrays networks to store sulfur.
• Porous carbon nanorods/S composites show improved properties.
• Realize enhanced cycle stability and rate performance due to integrated arrays.

Sulfur is an attractive active material for lithium batteries in terms of its high specific capacity and energy density. Despite main advantages, lithium sulfur (Li-S) batteries still suffer from great challenges with serious capacity decay and awful rate performance due to severe “shuttle effect” and mass loss of active materials. Herein we report a free-standing carbon-sulfur cathodes by anchoring sulfur into 3D carbon nanorods arrays. Binder-free and integrated characteristics are realized. Sulfur infuses into interspaces among arrays and trapped by the interconnected carbon arrays. The assembled cells exhibit initial discharge specific capacity of 1050 mAh g−1 at 0.2 C and 892 mAh g−1 at 2.0 C, companied by an outstanding coulombic efficiency of 98% after 200 cycles at 0.2 C. The obtained S-C cathode also shows excellent rate capacity with low capacity fade. The proposed new S-C architecture may pave the way toward construction of novel S-Li batteries.

Sulfur is well integrated into interspaces of carbon nanorods arrays networks, forming integrated composite electrode with enhanced electrochemical performance due to integrated high-conductivity hosts and improved binding force.Figure optionsDownload as PowerPoint slide