Figure 7 SEM images for (a, c) Li electrode and (b, d) Li-Na alloy electrode with a Na/Li molar ratio of 6 after five stripping/plating cycles in 0.5 M NaCF3SO3/TEGDME or NaCF3SO3/DOL/TEGDME electrolyte. (Reproduced from ref.[85], with permission from Copyright © 2018 The Author(s), under exclusive license to Springer Nature Limited.)
While a more common strategy to form an artificial SEI layer is using Li salts to in-situ react with lithium alloys. It is easy to realize a thin lithium alloy layers on the surface of Li metal by in situ reduction of metal salts as shown in Eqns 1[110]: