An interesting concept but it seems very unlikely this will be a prefered solution in 30 years as battery technology improves.
One problem with nerds that are living in the age of Moore's Law, is that they end up believing that other technologies enjoy the same sort of exponential improvements as semiconductors. In general, they do not. There will almost certainly be some incremental improvements, but I wouldn't bet on any big breakthrough in battery technology. If you look at the periodic table, there just isn't anything to the left or above lithium, except hydrogen which isn't practical for a number of reasons. It is extremely unlikely that we are going to discover a new alkali metal between lithium and hydrogen.
Of course, someone may invent "Mister Fusion", but that is not a battery.