This battery holder fits a large number of batteries and allows you to automatically sort your AA and AAA batteries. For me this was key, since my drawers always contain a whole mess of random batteries. Well, no more! The tolerances are quite tight, but it should fit your common AA and AAA batteries. Just let the battery slide down the shaft and watch it automatically go to the right side!

I designed it such that it can be printed in 5 parts without supports. The pegs and holes should align, which means that you won't need any screws to keep the two halves together! But if they don't quite fit, I recommend drilling out the holes with a small bit. Some sanding may be required as layers get a little squished, but hey, that's 3D printing right? I secured it all with a bit of superglue.

I originally made my V1 design for the Printables Battery Box Contest, which ended up getting to the third place! A massive thanks to all of you who voted, I never would have expected this! This new design is taller, but significantly less long, which lends it better to sitting on desks or shelves.

However, the model had a few flaws that made it somewhat unreliable and a bit of a hassle to use, so I took a lot of the feedback in mind and designed a completely overhauled version, which you see here! It took a lot of testing and I'll admit it became a little frustrating going back and forth all the time. Turns out a battery holder can be quite a complex design problem! But I'm very pleased with how this came out, and how well it works! Besides that, watching it work is surprisingly satisfying. Some of the main changes are listed below:

• This version uses a steeper ramp angle and tighter tolerances, which keep the batteries from sliding sideways and getting stuck with about 95% reliability.
• The capacity is now increased and both battery sizes won't interfere with eachother to the point where you would have to take out AA batteries for AAA ones to cycle through.
• The sorting is now based on battery thickness and works 100% reliably and is now done at the very top, which means clogging is no longer an issue (unless you load it up with a ton of batteries and fill it up completely).

The model uses more material than the first iteration, but in my opinion it is well worth it for the added reliability, storage capacity and ease of use. It prints in 5 parts without needing supports, which add up to about 20 hours using a 0.28 mm layer height.