Only if you declare the center as infinitely perfect in every way. If you allow each axis to trade off with the others, then there is no single ideal. Fixed storage would rather have better prices and cycles in exchange for worse density. Mobile devices would rather have better density in exchange for higher prices.
(You can look at it like a path through the solution space. If you keep letting someone pick which attribute to improve, over and over, you eventually hit infinity/infinity/infinity, but different users will take very different paths to get there. At any particular count of improvements, their ideal batteries are significantly different.)
And with regard to kickopotomus's comment, you can get away with a much higher cost if you're targeting the right niche.
