Untested design, please report any issues! A holder for a single button cell. It can be adjusted to almost any battery, or multiple cells if you add the height of the cells. Usage: Print and stick two pieces of wire through the holes in the sides. Slide in the button cell. If the fit is too tight, modify the parameters, starting with tolerance. Likewise if the fit is too loose, set tolerance to a smaller value. Example files: CR1225 cell holder: diameter=12mm height=2.5mm tolerance=0.5mm wall thickness=2mm CR2032 cell holder: diameter=20mm height=3.2mm tolerance=0.5mm wall thickness=2mm