Researchers from Argonne National Laboratory and Oregon State University have developed new cathode architecture for lithium-sulfur batteries. The team, led by ECS member Khalil Amine, incorporated graphene and sulfide nanoparticles to improve electrical conductivity in the promising lithium-sulfur batteries.
Lithium-sulfur batteries hold major promise as researchers explore the range of energy storage technologies. With an extremely high theoretical energy density, these batteries have the potential to store up to five times as much energy as today’s best lithium-ion battery.
But there are barriers preventing that theoretical density from becoming an actual density. Namely, the discharge products of sulfur electrodes and cycling intermediates produced.
This from Nanotech Web:
[Amine’s team] at Argonne has now succeeded in making a new type of Li-S electrode architecture from crystalline Li2S nanoparticle encapsulated in few-layer graphene. The Li2S@graphene nanocapsules formed can accommodate the maximum amount of active sulphur species (as much as 10 mg of Li2S/cm2) and boast superior electrochemical properties. Indeed, the electrodes have a high reversible capacity of 1160 mAh/g and area capacity of 8.1 mAh/cm2.
“Other advantages of the design are that Li2 nanoparticles only form in the presence of co-formed graphene layers, so the graphene framework functions as an overall electrical conduit,” explains team member Jun Lu. “This means that nearly all of the Li2 nanoparticles in the electrode are electrochemically active. The compact graphene shells also have good physical properties and preserve the structural integrity of the composites.”