A stable room-temperature sodium-sulfur battery.
High-energy rechargeable batteries based on earth-abundant materials are important for mobile and stationary storage technologies. Rechargeable sodium-sulfur batteries able to operate stably at room temperature are among the most sought-after platforms because such cells take advantage of a two-electron-redox process to achieve high storage capacity from inexpensive electrode materials. Here we report a room-temperature sodium-sulfur battery that uses a microporous carbon-sulfur composite cathode, and a liquid carbonate electrolyte containing the ionic liquid 1-methyl-3-propylimidazolium-chlorate tethered to SiO2 nanoparticles. We show that these cells can cycle stably at a rate of 0.5 C (1 C=1675, mAh g(-1)) with 600 mAh g(-1) reversible capacity and nearly 100% Coulombic efficiency. By means of spectroscopic and electrochemical analysis, we find that the particles form a sodium-ion conductive film on the anode, which stabilizes deposition of sodium. We also find that sulfur remains interred in the carbon pores and undergo solid-state electrochemical reactions with sodium ions.
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Shuya
S
Wei
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Shaomao
S
Xu
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Akanksha
A
Agrawral
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Snehashis
S
Choudhury
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
Yingying
Y
Lu
Department of Material Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
Zhengyuan
Z
Tu
Department of Material Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
Lin
L
Ma
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Lynden A
LA
Archer