Highly reversible cycling with Dendrite-Free lithium deposition enabled by robust SEI layer with low charge transfer activation energy.

[Display omitted] • Low charge transfer activation energy is realized with the Li 3 N/LiF SEI layer. • Stable cycle performance with dendrite-free Li is abled in Li/Cu and Li/Li cells. • Outstanding cyclability is demonstrated in full cells using LiNi 0.8 Co 0.1 Mn 0.1 O 2. Li dendrite growth and poor Coulombic efficiency still prevent the practical use of Li metal anodes. Here, we report a stable solid electrolyte interphase (SEI) layer consisting of Li 3 N and LiF by employing lithium nitrate (LiNO 3) in carbonate electrolytes for the improved cycle performance with dendrite-free Li deposition for Li metal anodes. We demonstrate that the lower charge transfer activation energy is realized with the Li 3 N-rich SEI layer and LiF-rich SEI layer in carbonate electrolytes. With the Li 3 N and LiF composite SEI layer, outstanding improvements are achieved in that the very low charge transfer activation energy of 46.64 KJ mol−1 and stable electrochemical performances with dendrite-free Li deposition. With those benefits, the Li || Cu cell shows stable cyclability with high Coulombic efficiency of ∼ 97% at a current density of 0.5 mA cm−2 with a capacity of 0.5 mAh cm−2 over 200 cycles, and Li can be densely plated with lower porosity of 10.1 % with a plated Li of 2 mAh cm−2. Finally, the outstanding cyclability is demonstrated in full cells consisting of LiNi 0.8 Co 0.1 Mn 0.1 O 2 as a cathode and thin Li metal electrode with a thickness of 20 μm in lean electrolytes of 8 μL mAh−1. [ABSTRACT FROM AUTHOR]