Lithium is pretty cheap and abundant; if it becomes a problem we'll just have to figure out how to extract it in less efficient ways (from sea water, perhaps?).

Lithium is pretty cheap and abundant; if it becomes a problem we'll just have to figure out how to extract it in less efficient ways (from sea water, perhaps?). Cobalt is a bigger bottleneck resource. Without details, it's hard to know if this Toyota battery require cobalt (or some other expensive rare-earth mineral). Most lithium-ion chemistries require cobalt, and a lot of the advances and cost improvements in recent years have been around figuring out how to use less. LiFePO4 doesn't use cobalt at all, but has mediocre energy density.