I liked the original Stackable Battery Holders but they were missing one piece of information important to me: battery charge level.
So I swapped battery size for self-generated simple icons that show "full" or "empty" as I store rechargeable AA (eneloops) in them.
Note that this Remix only covers AA size, not all available sizes from the original (as I didn't need them).
Print the front face-down and bridge the battery icon inlets. Print the back with its flat side down as well (where holes exist for wall-mounting).
As is the case with most of my Things, I friction-welded the final product together (except for the icons, see below). Might not have been strictly necessary but it's a habit at this point.
The icons were intended to fit right in, but mine didn't.
So I just dumped a ton of hot glue into the recessed part and stuck them on.
I colored them with sharpies.