Solid-state batteries containing a Li anode and a ceramic electrolyte offer a possible route to higher energy density and increased safety, compared with liquid electrolyte Li-ion batteries. Charging at practical rates can lead to the formation of Li dendrites at the anode which penetrate the ceramic electrolyte, leading to short circuit and cell failures. Furthermore, forming solid-state cells free from Li metal initially are attractive but come with problems, including inhomogeneous Li distribution, which can compromise cycling.
In this paper*, Dr Dominic Jolly-Spencer and his colleagues employ operando powder X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy to follow the structural changes in an Ag-graphite composite interlayer as a Li-free cell is charged then discharged. The fundamental understanding of the Ag-graphite composite layer in their experiments provides a path toward the design of interlayers that enable improved solid-state battery performance, with implications not only for the Ag-graphite composite layer, but also for carbon-based interlayers more widely.
*'Structural changes in the silver-carbon composite anode interlayer of solid-state batteries' (Joule, Vol 7 Iss 3 March 2023 pp. 503-514)