Again not far. Fuel cells to be used that allow for storing solar reliably, by all means, provide the evidence of the fuel cell industry making this possible not wishful proprietary technologies
Hang on, so, you want fuel cells but dismiss someone building the world's largest battery using redox flow technology?
I take it that you don't know that redox flow batteries are a type of reversible fuel cell? https://en.wikipedia.org/wiki/Flow_battery#Redox
One thing, I take it you don't see lithium scaling. Why is that? There is enough of it.