Prior to imaging, the substrate was rinsed 3 times with EC:EMC with a ratio of 30:70 wt. % (Elyte, Germany) for 5 min followed by drying inside the argon glovebox for 15 min to remove the dried LiPF6 salt excess. Optical images of a SDC tip, perforated Kapton film and wetted area of the spots on a substrate were captured using Keyence VHX 7000 optical microscope (Keyence, Germany) at 500 x magnification with the Stitching 3D Imaging option in HDR mode. The area analysis was performed using the maximum area measurement function of the microscope software.