Researchers from Australia's Monash University and CSIRO Manufacturing have designed a permselective membrane based on reduced graphene oxide (rGO) for making practical lithium-sulfur batteries.
The membrane closely mimics a cell plasma membrane, demonstrating selective Li+ transport and the ability to not only retain polysulfides, but also 're-activate' them on the membrane's electrochemically active interface. The team used the membrane to demonstrate high loading and high rate Li-S batteries, also on a pouch cell level.
The team's membrane utilizes conductive reduced graphene oxide as a brick-like framework, with an elastic polymer liquid—rich in ion hopping and lithiophilic sites—as the mortar.
The membrane mimics cell plasma membranes by integrating rapid and permselective Li+ channels alongside catalytic electrochemical reactions.
Using the reactive permselective membranes, the team attained areal capacities of 4.8–8.1 mAh cm−2 with 450 stable cycles in coin cells and 202 Wh kg−1 with over 100 stable cycles in pouch cells. This behavior is achieved with efficient electrolyte/capacity ratios (4.9–5.3 μL mAh−1).