by Erin Cassidy Hendrick
UNIVERSITY PARK, Pa. — Rechargeable lithium metal batteries with increased energy density, performance, and safety may be possible with a newly-developed, solid-electrolyte interphase (SEI), according to Penn State researchers.
As the demand for higher-energy-density lithium metal batteries increases — for electric vehicles, smartphones, and drones — stability of the SEI has been a critical issue halting their advancement because a salt layer on the surface of the battery's lithium electrode insulates it and conducts lithium ions.
"This layer is very important and is naturally formed by the reaction between the lithium and the electrolyte in the battery," said Donghai Wang, professor of mechanical and chemical engineering. "But it doesn't behave very well, which causes a lot of problems."