9V batteries are often found in devices that aren’t used very often. If you use a NiCd rechargeable battery you may find it completely discharged by the time you need it. Capacitors on the other ...

All of the common disposable alkaline batteries from AAA to D are single cells. The exception is the 9v battery which actually has six smaller cells inside of it. [Tom] took a look inside three ...

You want the file lego_powered_up_battery_box_v5.stl. Print it with the base flat on the print bed. PLA should be fine, though I used PETG for mine. Print overhangs slowly. See my related blog post ...