Apparently the battery plant Tesla built in Australia only powers 30k homes which is a tiny amount. They are working to 'double' the capacity, which I assume goes from 30k to 60k.

It seems to be making net-positive amount of money and Tesla built it in record time but sourcing that much lithium to build it for millions of people across the country sounds like a tall order, not to mention the 2-5x costs/time any major public works infrastructure project would add based on recent history of all of them in western countries (for ex: both of Obama's clean coal and solar project went bust, before roll out, after billions spent each and many years, so outright failure of even top-down federal-level projects must also be considered).

I'd be curious to hear an expert speculation on the matter for what a practical battery farm deployment would look like. Which would likely need to exist, assuming we're abandoning backup energy sources like nuclear and natural gas.