These guys in the US make a 500kwh version, that can run at 75kw of discharge power across 3 phases, and its a single shipping container: https://essinc.com/energy-warehouse/
It doesn't seem like it would take up that much space to have 200 shipping containers sitting somewhere, i'm pretty sure the Home Depot distrubution center in our town already is close to that in their parking lot (yes, you would want them not on wheels, and farther apart)