Sulfur-Based Catholyte Solution with a Glass-Ceramic Membrane for Li-S Batteries

Shuttling of soluble polysulfide species within electrodes is one of the most challenging issues in lithium-sulfur (Li-S) batteries. The resulting deposition of polysulfide species reduces the conductivity of the metallic Li electrode and the quantity of active material. Here, we demonstrate pronounced suppression of polysulfide shuttle using a sulfide-impermeable glass-ceramic membrane, which is employed as separator between the positive and negative electrodes. As a result, highly stable Li-S electrochemistry occurs in the sulfur-dissolving tetrahydrofuran catholyte solution, which provides good capacity retention and Coulombic efficiency for cycling. This demonstration holds promise for practical next-generation batteries with marked reversibility and the possibility to increase the energy density when equipped with a catholyte flow-through mode.