Where does this market start and stop?
Before any number, we pin down what counts as a solid-state battery, because the label gets stretched a lot.
A cell with a fully solid electrolyte is in. A hybrid design that keeps some liquid is in too, but counted on its own. A regular lithium-ion cell with a new name, or a company that only recycles batteries, is out.
That way, a startup's press release and our charts speak the same language.