Electrolyte decomposition and the formation of the solid-electrolyte interface SEI depends critically on the used active materials, electrolytes or electrolyte additives. A better knowledge of the initial steps of SEI formation is thus necessary to cope with new active anode materials or new electrolytes. The initial wetting as well as the further SEI growth are critical for the stability of the applied battery system. Here we present the use of different surface sensitive techniques to address the SEI formation. Next to Synchrotron-based high-energy or hard x-ray XPS (HAXPES) or AFM we belief that studies employing a surface force apparatus (SFA) may play a more prominent role in the future. We report first results on using an electrochemical SFA setup which was modified for addressing battery interfaces. The SFA technique detects changes in layer thickness together with the mechanical behavior of the growing surface films. The potential-induced SEI formation was followed first on Au, but also the initial wetting behavior of a EC/DEC electrolyte on model electrodes such as mica, gold or graphene was studied providing an unprecedented insight in ultrathin wetting layer formation under confined conditions.