The CAD Guy and Airwaves Ted created both nice Battery storage systems. I prefer the more simple version of Ted´s design (doesn´t need an additional bottom to be stackable) but both look great! 

Here I remix the empty box to be printed easier as the original one.

I hope this might help some of you, because the original ideas are very nice :)

Have fun and keep printin and thank you Ted for your design!

PS: This Box ist Designed to be scaled to your needs :)

New: Box 4 18650 Batteries. (This model is prescaled to 80%)

I printed Mine in PLA, 5-10% infill and 130% Speed 0,2 mm