Whether you asked for a curved phone or not, they're already a convex reality. One that introduces a few manufacturing twists. A curved screen is one thing, but what about other large components like the battery? Samsung sidestepped this issue in the Round by making it narrow and tall, but there's still a limit to the amount of curve available. A new flexible battery developed at the New Jersey Institute of Technology could solve that. The cell uses carbon nanotubes, and is not only flexible (like other examples we've seen), but entirely scalable -- suitable for tiny or large electronics alike. Not only would this mean roll-up batteries, the researchers claim it could easily be made at home with the right "paste" and a laminating machine.