Gridfinity 3x5 Ultimate Battery Holder (AA, AAA, AAAA, 2032, LR44, A97, 18650, 9v)by
Designed to interface with Zack Freedman's #Gridfinity system. Dedicated spots for bulk AA, bulk AAA, AAAA, 2032 (CMOS battery), A97/LR44/Other (Calipers, etc.), 18650 and 9-volt batteries. Prints well with 0.4 or 0.6 nozzle.
Supports not necessary unless you're using the magnet holes in the bottom, in which case you'll want supports on "touching buildplate" mode. Tolerances are tight at ~0.5 mm due to the sizes of the batteries and needing to stick to 3-unit-wide model, but this should be achievable with pretty much any printer. For best printing, only adjust horizontal expansion if necessary to fit the batteries since the walls are all modeled to multiples of 0.4mm. Changing horizontal expansion will likely increase print time and reduce quality.