[zippy]

unless someone has a plan to burn and spew the old cells into the atmosphere, causing the earth to heat up, it will never be as big a problem as gas cars.

(that is the worst case, where auto makers just bury the cells in the ground. thankfully, that's not actually the case. they reuse battery packs and are scaling up techniques to recover the rare metals from them. you haven't heard much about this at scale because few packs have actually hit their end of life.)