Lithium sulfur (Li-S) redox flow battery (RFB) is a promising candidate for high energy large-scale energy storage application due to good solubility of long-chain polysulfide species and low cost of sulfur. In this report, recent progress and new concepts for Li-S redox flow batteries are discussed with an emphasis on the fundamental understanding and control of lithium polysulfide chemistry to enable the development of liquid phase Li-S redox flow prototype cells. These differ significantly from conventional static Li-S batteries targeting for vehicle electrification. A high solubility of the different lithium polysulfides generated at different depths of discharge and states of charge is required for a flow battery in order to take full advantage of the multiple electron transitions between elemental sulfur and Li2S. A new DMSO-based electrolyte is proposed for Li-S redox flow batteries, which not only enables the high solubility of lithium polysulfide species, especially for the short-chain species, but also results in excellent cycling with a high Coulombic efficiency. The challenges and opportunities for the Li-S redox flow concept have also been discussed in depth.
Revised: July 18, 2016 |
Published: April 27, 2015
Citation
Pan H., X. Wei, W.A. Henderson, Y. Shao, J. Chen, P. Bhattacharya, and J. Xiao, et al. 2015.On the way toward understanding solution chemistry of lithium polysulfides for high energy Li-S redox flow batteries.Advanced Energy Materials 5, no. 16:Article No. 1500113.PNNL-SA-107502.doi:10.1002/aenm.201500113