This is a simple cradle to take a AAA rechargeable battery and allow it to easily fit into an 18650 battery slot.

The Nitecore charger I have doesn't accept the AAA all that well, they need to be held in place just correctly. This cradle is only 20mm long and supports the AAA battery in the middle, allowing it to contact the terminals correctly. 

No more partially charged batteries because they moved a little under the pressure of the terminals.

In the images, the YELLOW part under the orange battery is the cradle.

Printing

Ideally you want to print these on their edge, so they grow upwards. This means you do NOT need any support.

• Nozzle width: 0.4mm
• Layer height: 0.2mm
• Infill: 20%
• Infill type: Anything, there isn't much, they are small
• Skirt

The default orientation needs changing, as I designed it in the wrong plane.

Material

I used PLA, but anything will be fine. The batteries will get warm, but nothing that should worry the material.

Resizing

If you want to make it longer, simply stretch it along the length to increase the size. Though the 20mm of the model should be fine.

Other sizes

If you would like one to convert from AA, please leave a comment and I will upload a suitable model.