Induction/Inhibition Effect on Lithium Dendrite Growth by a Binary Modification Layer on a Separator

In lithium metal batteries (LMB), unrestricted growth of lithium dendrites will pierce the separator and cause an internal short circuit. Therefore, we designed modified separator with an InN thin layer, which could be in situ converted into a binary mixed-modified layer of Li-In alloy and Li₃N during the lithium plating/stripping process. Among them, Li-In alloy induces the lateral growth of lithium dendrites and prevents the separator from being pierced; Li₃N balances ion distribution at the lithium anode/separator interface, which is beneficial to inhibit the growth of lithium dendrites. Under the synergistic effect of the two phases, the performance of LMBs was obviously improved. In addition, the separator modification does not need to be carried out in a protective atmosphere and is suitable for large-scale roll-to-roll processing.