101% outer scaling for me, PLA outer, 95A TPU inner.

Great design! Thanks for sharing.. Outer component printed in PLA at 102% gives a snug fit but is easily removed if need be.
A little too tight, but still a great idea. Thanks for sharing. I added a logo for identification.
@Mici nice :) - if you dont want it really tight then print the outer case at 102%
Great print! It was pretty tight and I don't think I can get it off without destroying it, but I think that is partly the fault of my printer not being tuned and partly because it is supposed to be tight.
Excellent idée ;-)
Nice clean design! I might need to re-print the outer piece again at 105% scale or so. As is, there is very little tolerance between the two pieces and it will be hard to get them apart when it comes time to change the battery. I printed the inner in Overture TPU and the outer in Overture PETG, so its possible that affected the fit. Good luck in the contest!