(327a) Toward Solid-State Lithium–Sulfur Batteries through Solid Electrolyte Engineering

Authors: 
Agrawal, A., The University of Texas at Austin
Helms, B., Lawrence Berkeley National Laboratory
Solid-State lithium–sulfur batteries are attractive for the electrification of
vehicular powertrains, particularly for light- and heavy-duty trucks and
aircraft. Both the lithium anode and sulfur cathode undergo large volume
changes while cycling, which places strict demands for the compliance and
conformal nature of the embodied solid electrolyte. Additional design
considerations regarding the solid electrolyte include ionic conductivity,
charge transfer resistance with both electrodes, and the manufacturability,
given sulfur cathode architectures are highly nanostructured and thus high
surface area. Here, we will describe our recent efforts in designing solid
electrolytes within this design space. A specific focus will be placed on
interface stability on both electrodes, where various electrolyte formulations
meet targets for ionic conductivity (e.g., >1 mS/cm at 20 ÌŠC) but exhibit
surprising yet revealing differences in both interfacial stability and
impedance to charge transfer. We will also discuss how optimized
electrolytes can be used to study sulfur speciation throughout the solid-state
electrochemical conversion reactions incurred while cycling the solid-state
battery, via operando x-ray measurements.