Long-Life, High-Rate Lithium-Sulfur Cells with a Carbon-Free VN Host as an Efficient Polysulfide Adsorbent and Lithium Dendrite Inhibitor

Lithium-sulfur (Li-S) batteries are a promising next-generation energy-storage system, but the polysulfide shuttle and dendritic Li growth seriously hinder their commercial viability. Most of the previous studies have focused on only one of these two issues at a time. To address both the issues simultaneously, presented here is a highly conductive, noncarbon, 3D vanadium nitride (VN) nanowire array as an efficient host for both sulfur cathodes and lithium-metal anodes. With fast electron and ion transport and high porosity and surface area, VN traps the soluble polysulfides, promotes the redox kinetics of sulfur cathodes, facilitates uniform nucleation/growth of lithium metal, and inhibits lithium dendrite growth at an unprecedented high current density of 10 mA cm(-2) over 200 h of repeated plating/stripping. As a result, VN-Li||VN-S full cells constructed with VN as both an anode and cathode host with a negative to positive electrode capacity ratio of only approximate to 2 deliver remarkable electrochemical performance with a high Coulombic efficiency of approximate to 99.6% over 850 cycles at a high 4 C rate and a high areal capacity of 4.6 mA h cm(-2). The strategy presented here offers a viable approach to realize high-energy-density, safe Li-metal-based batteries.