Anodic Behavior of Lithium in Aqueous Electrolytes: I . Transient Passivation

Lithium manifests a transient passivation when it is anodically polarized to ∼ −2.66 NHE in electrolytes. The duration of the passivation ranges from seconds to hours. The occurrence of the passivation is independent of electrolyte concentration, flow velocity, anode‐cathode contact pressure, and of the polarization technique used. The duration of the transient is proportional to electrolyte concentration, the more dilute the solution the shorter the time. The passivation is believed due to the formation of an insulating, but unstable aggregate of which nucleates at active Li sites at the base of the pores in the protective film. The recovery of the surface to the active state is due to the conversion of the to in the presence of water at the Li surface.