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DOE OSTI · 1976284

Anode-Free Lithium–Sulfur Cells Enabled by Rationally Tuning Lithium Polysulfide Molecules

Ren, Yuxun·Bhargav, Amruth·Shin, Woochul·Sul, Hyunki·Manthiram, Arumugam
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Abstract

The two major barriers of practical lithium–sulfur batteries are the poor reversibility of lithium-metal anode and sluggish kinetics of sulfur cathode. Here, we report a simple yet cogent, molecular tailoring approach for lithium polysulfides, enabling a synergistic enhancement of anode reversibility and cathode kinetics. In this study, we show that SnI 4 coordinates with lithium polysulfides to form soluble complexes, resulting in a Li 2 SnS 3 -rich anode interphase layer. As Li 2 SnS 3 is stable against parasitic reactions and has a lower ionic resistance over cycling, the Li plating/stripping efficiency is greatly improved. In addition, the formation of soluble complexes between SnI 4 and lithium polysulfides play a non-negligible role in suppressing the clustering behavior of lithium polysulfide molecules, resulting in a significant enhancement in sulfur conversion kinetics under lean electrolyte conditions. The synergistic improvement is validated in anode-free, lean-electrolyte pouch cells with a Li 2 S cathode that displays capacity retention of 78 % after 100 cycles.

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25 ENERGY STORAGEanode solid electrolyte interphaseanode-free batteriesanode-free cellsbatteriescathode kineticselectrolyte additivepouch cells

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Ren, Yuxun, Bhargav, Amruth, Shin, Woochul, Sul, Hyunki, Manthiram, Arumugam. 2022-07-07. Anode-Free Lithium–Sulfur Cells Enabled by Rationally Tuning Lithium Polysulfide Molecules. https://doi.org/10.1002/anie.202207907

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