But chemical batteries cost a lot more and don't have lifespans of hundreds or thousands of years in seasonal storage scenarios.

And when electricity is in essence too cheap like with solar and wind it can be, losing half in efficiency actually doesn't matter too much.

> But chemical batteries cost a lot more and don't have lifespans of hundreds or thousands of years in seasonal storage scenarios.

Practically speaking, you're probably not going to get 1000s of years out of any storage method. There's just too much stuff that breaks down.

Heck - a lot of historic dams are in the low hundreds of years old and are experiencing serious problems.

IMO, the shorter lifespan of batteries isn't that big of a downside as long as the "bad" batteries can be mined for raw materials eventually.