Sounds like you want the Samsung Galaxy X[0]. If it runs Dex (unclear right now) you'll get desktop Linux in a foldable phone with bluetooth capabilities. I believe the screen is going to be 7.3" but not sure if that's unfolded or folded.
Sounds pretty awesome. I'm keen to see what it ends up being. Not sure why they would need a curved battery. I'm imagining it like a book, with just a normal flat battery each side. Maybe they're thinking like a loosely folded piece of paper before it creases.