That just means you get to scale it independently.

While they both need to scale the amount of DC<>AC inverters based on peak power demand. If you want to discharge over 16 hours you’re using 2% of lithium ion’s peak power output and need a huge mess of wiring to move power from each internal cell to that inverter + complex battery packs with individual electronics cooling etc.

Flow batteries on the other hand can use a single pump (+ redundancy) and fat pipe to supply a huge array of ion-exchange membranes which then sit next to the inverters.

Energy storage is the problem that needs a solution, e.g., storage from summer to winter.

Annual and long-tail storage are both problems that need solving, and fuel cells do look like a possible solution. But it's not clear at all what the winner will be for those applications.

Even hydrogen is competitive here. IMO, more competitive than that battery chemistry on the article.

Fuel cells are a possible solution (especially if one can build a dual mode electrolyzer/fuel cell), but combined cycle power plants burning hydrogen would also work, if only at very large scale (but then economical hydrogen storage likely requires large scale).

Seasonal energy storage is the last thing that needs to be addressed in the storage hierarchy. There are very high-value targets starting on very low time frames.

Seasonal energy storage is the last thing, but that also means it's the last caveat, as far as I can tell. If we figure out seasonal energy storage, that's it. Solar just wins. There's no further need for fossil fuels. We're done.

I guess there's still aircraft.