Presenting a triple 18650 Cell end cap.

I had a need to fit 3 18650 into this (https://makerworld.com/en/models/2859961-guition-4-esp32-s3-4848s040-cases) excellent case for my Guition ESP32-S3-4848S040 which I wanted to power.

Nothing quite fit my needs, so I came up with this with the help of Google Gemini and OpenSCAD Playground.

Simply put, it allows you to arrange 3 18650 cells, that will fit nicely into the linked case above.

Wiring the end caps up with 22AWG single core is fairly straightforward, just strip about 50mm and feed through each of the smaller holes by the dimples to create a contact for each cell. Tweezers will help. Snip any excess once complete.

There is a centre hole allowing you to run either your positive/negative to either end, or back into the middle of the pack. Be sure to apply some kapton tape to the ends once wired.

Secure with a cable/zip tie, one is sufficient.

Photo is from an earlier iteration that had 12mm depth, this is now 5mm. Scale the Z axis if you want more depth.