The problem is that we're hitting the limits of what's feasible with current technology. Without a revolution in material science, we're likely stuck with incremental improvements in batteries.
Fuel cells and hydrogen storage will benefit drastically from increased R&D and economies of scale. Something as simple as thinner membranes and catalyst layers will dramatically reduce cost, but until recently there has been minimal effort in such ideas. Same is true of just having more production facilities.
There are numerous new ideas being explored for hydrogen storage. Only this year has someone figured out how to make a true hydrogen "battery" for you home: https://dlmag.com/lavo-hydrogen-hybrid-battery-stores-electr...
