Ferric chloride steers lithium away from dendrites to improve safety of lithium-metal batteries
Common chemical additive challenges the assumption that stiffer electrolytes are needed to suppress dendrites
Ferric chloride (FeCl₃) could help solve one of the biggest safety challenges facing solid-state lithium-metal batteries. Researchers found that adding the widely used industrial chemical to polyethylene oxide-based electrolytes promotes the growth of lithium as spherical particles rather than needle-like dendrites. Surprisingly, the additive also softens the electrolyte, challenging the long-held view that strong electrolytes are essential for suppressing dendrite growth during battery cycling.