Fig. 1: Single-ion-conductor-based composite layer.

a Schematic illustration of the effects of the S-CE/B-GE and S-CE/S-GE composite layers on the cycling stability of liquid electrolyte-based LMBs. b Optic and FIB-SEM images of S-CE/S-PE composite layer coated on Li metal electrode. c STEM-EDX mapping of S-CE/S-PE composite. Scale bar: 500 nm. d TEM image and SR-EELS image recorded with scanning across the S-CE/S-PE interface at the Li-K (55–70 eV) and La-N4.5 (100–140 eV) energy loss region. e The corresponding intensity profiles of Li-K and La-N4,5.