18650 Circuit Case

thingiverse

This is a dual 18650 case, originally designed by tekhertz, with modifications made to mount a circuit board on top and include a cover for the circuitry. To make it compatible with the modified design, I increased the height of the end-caps to meet the circuit cover, and added built-in faux supports so they can be printed at 0.2mm layers without support material. After printing, a single layer can easily be punched through with a file or drill. Two versions of the caps are available: one without any holes, and another with a cutout designed for two USB ports side by side. Although the photo shows cutouts in the circuit cover, these were not built into the model as they are specific to my custom circuit design. I recommend cutting out any necessary holes for buttons or switches from the printed model itself instead of modifying the original design if possible. The end caps attach to the core with M3 screws and nuts. To connect the battery posts, I found that pairing M3x8 screws with half a spring from a clicky pen attached to one side worked well. The circuit cover and circuit board mounting holes are designed for use with M2.5x4 screws. Wiring setup: The end caps have a channel cut in them to connect the ends of the batteries together. To run wires from the batteries up to the circuit, I filed two small grooves into one side of the core where wires can pass through. This is the end where I attached the springs to the M3 screws and consider this end permanently attached, only removing the other free end to change the batteries.