I printed the original to store batteries safer in my tool bag and to make storage in the bag cleaner.
After printing the original battery stacker and inserting two batteries, i realised that the battery clips were under constant tension, which could in turn make the clips fail prematurely.
So i measured the inner part of a tool to find it had a 63mm width and not the 60mm on on the stacker, a quick dip into TinkerCad and a widened clip socket.

All kudos to the original design, its clean and practical,