December 11, 2022
Description
Use this model to directly wire AA battery electronics to an external power source. The dummy battery is designed to fit in a AA battery slot. Small holes are provided so you can easily slide some 22AWG solid core wire through so electrical contact can be maintained with the battery terminals. This model is designed to maximize the space in a battery slot for other electronics. Small slots are added to place zip ties if you would like to further secure the wires. This model should not require support material if you print with the long side face down. I included the Fusion 360 file if you would like to edit/remix this design further.
The motivation behind this model is to convert Walmart Battery Powered Candles to USB powered since the AA batteries are depleted in less than 3 months on the 6hr daily timer setting. I soldered protoboard featuring a 5V to 3V regulator circuit using an LM338T. You could also use a compact regulator module like the Pololu 3V Step Down Regulator. The entire circuit board fits within the battery slot so that the original battery cover can be used. I ended up drilling a hole in the battery cover so that I could feed the wires out. Other than that minor modification, the candle later can easily be converted back to battery powered by removing the dummy battery adapters.
License:
Creative Commons - Attribution