It will be patented - yes. Sat on at a very high price - I don't think so. Even if you only think about maximizing profits, with a technology like this you would make much more money by creating a new market (mass produced electric cars) with lower margins and very big numbers than with high margins and very little numbers.

On the other hand, if the technology required to mass produce this kind of batteries will be too new, it could take time to scale it and bring costs down. Let's hope it isn't too innovative.