Why fixate on renewables that need batteries? Inherently safe, next-generation nuclear, preferably MSR, is the way to go, actually.

@User65535, yes, thanks for rounding that out

@juhist yes it is. it's a fact check on an arbitrary statement, giving the most possible generous amount of lithium: all of it, not only the amount that could be mined; the ad extremum is the point, to show that the statement is wildly incorrect (even though I agree with him on other points). If there were enough in the the crust, the answer could be further refined to reflect how much could be mined. Do you see how the simpler, extreme calculation is more powerful, faster, and by definition rules out the more complicated "how much can we mine?" calculation. That is not necessary.

The calculation looks good. Can you expound on your statement that no one would store 4 months of electricity in batteries? Do you mean they would store less (perhaps the difference between total average demand and average supply from renewables during all of Winter, minus the amount of energy obtained elsewhere), or they wouldn't store it at all?

@andyyy I agree re. the flow batteries. I've heard them called liquid metal batteries, and they've been proposed as preferable for grid storage. I agree that there is some solar and wind power in the winter, but not enough to meet average, let alone peak, demand; it has to be supplemented with some kind of base load.