Flexible modular battery holder

Make the combination you want. Single row of modules or double row.
I use it mainly for nearly unused batteries removed from decoration light and similar.

But you can also use this color code
Green: new battries
Yellow. Battries still with power, hardly used.
Red: old batteries, can be thrown out.

They interlock nicely printed on my BambuLab P1S wit original PLA. I have also tested it on Prusa. If you want to move it around with batteries, you'll probably need glue.