Lithium dendrites: an extreme manufacturing problem

Lithium dendrites are usually treated as electrochemical instabilities, but recent nanomechanical measurements show that the deposited lithium filaments responsible for battery failure can behave as strong and brittle nanoscale composites. This article discusses how air-free mechanical testing, cryogenic electron microscopy and solid-state battery fracture studies reshape the understanding of lithium penetration, dead lithium formation and interfacial degradation. The emerging picture is that dendrite suppression requires extreme-manufacturing control over the formation, constraint and fracture of lithium at buried interfaces, rather than only higher electrolyte modulus or improved electrochemical stability.