Fig. 2: Operando visual investigation of the lithiation and plating/stripping process by optical cell at different cycling currents.

The timestep numbers stamped on the optical images correspond to the ones in the voltage profile. The field-of-view of the optical microscopy shows the first 400 μm of a total thickness of 2.2 mm (i.e., in-plane horizontal direction). Source data are provided as a Source Data file.