(S)TEM: LLZO lamellae for (S)TEM were prepared by FEI Helios NanoLab 600i DualBeam with final polishing at 5kV Ga + beam with a Pt capping layer (200 nm from electron beam induced deposition followed by ~1.5 µm from Ga + beam induced deposition) to protect the surface from Ga beam damage. Then lamellae were transferred to cryogenic dewar and immersed in liquid nitrogen to avoid air reactivity before loading to (S)TEM. For cryo-EM characterization, the lamellae, while still immersed in liquid nitrogen, were loaded into the Gatan side-entry cryo-transfer holder (Gatan model 626), which was then inserted into the (S)TEM column. To maintain the specimen in its native state, a specialized cryo-shutter was employed within the cryo-EM holder, preventing air exposure and ice condensation onto the sample. Once inside the TEM column, the temperature was maintained at approximately -174 ºC to achieve the cryogenic conditions required to minimize beam damage during operation. Cryo-EM