The thing is that li ion batteries bare these 10 years ahead. So to be competitive now, a battery chemistry bmust be either 10times cheaper (rough estimate) or fill in a niche application (high density, very stable). A battery that is just five times as cheap will never catch up to the learnings of li ion manufacturing.
But that calculation is affected by the commodity prices of lithium as well. If demand for batteries increases (i.e. if most people started driving electric cars) then a technology could go from 5 to 10 times as cheap very quickly
