Schematic drawing of the SDC setup: the 3-electrode electrochemical cell with an opening is in contact with a substrate (WE), and a tight sealing is controlled by a force sensor. The electrolyte flow is regulated with a syringe pump. The coordinates of the cell are controlled using high-precision stepper motors. All the abovementioned components are located inside the inert and dry argon glovebox. All the actions of the setup and electrochemical procedures are controlled using a PC and a potentiostat outside of the glovebox (a). The rendering of the scanning droplet cell cut in contact with Au substrate (WE), Li on Pt (CE) and Li on Cu (RE) are placed as close as possible to the tip opening without touching each other; the rendering of homemade lithium, lithium-gold, and commercial silver-ion (222) REs (b). 36 cyclic voltammograms for the reproducibility tests using Fc/Fc + redox couple using Li RE. A half-wave potential is in the middle of oxidation and reduction peaks (c). The half-wave potential Fc/Fc + redox couple over the long-term experiment (up to 48 h) was measured using the various REs. The potential during the first measurement (t = 0) was considered as E0, all other potentials were compared with this value (d).