PASSIVATING LAYER ON LITHIUM IN LITHIUM TETRACHLOROALUMINATE-SOCl₂ SOLUTIONS.

Results a detailed model describing the electrochemical behavior of alkali and alkaline earth metals in non-aqueous battery systems was presented. According to this mode these metals are always covered by a surface layer at least 15A thick. This layer acts as an interphase between the metal and the solution and has the properties of a solid electrolyte. The properties of this solid electrolyte interphase (SEI) govern the electrochemical behavior of these systems. The goal of this work was to study the properties and the growth rate of the passivating layer on lithium in LiAlCl//4-SOCl//2 solutions. Results show that the lithium electrode is always covered by a passivating film. Its minimum thickness in the case of freshly immersed electrodes or after anodic dissolution was about 20-40A. The overall growth rate of the passivating layer (including the SEI and the large crystals) is governed by two porcesses.