It is highly dependent on the chemistry of the battery. Batteries can have extremely long lives though, so even when a battery is done in an EV, it can go on to serve as a household solar power storage unit for another decade or more. A gas engine can't really compete with that. Gas engines, and their transmissions, are incredibly complex even just from a metallurgy standpoint. The amount of time and energy that goes into creating and transporting all of those parts is mind blowing.
That said, there have been some relatively recent battery breakthroughs that will, in future, reduce the amount of rare earth metals used in batteries. Telsa has already implemented them in some of their cars. The batteries are smaller and lighter for the same power output and range.
There are two main points to EVs:
1. It makes the method of propulsion fuel agnostic. It doesn't matter if you have coal, natural gas, wind, hydro, solar, rooftop solar, nuclear, or a hamster running on a wheel generating electricity. The car doesn't care. If all of the sudden we can't use coal anymore, there's 5 or 6 more options to switch to and you don't even have to think about it, your power company does that.
2. Even if you charge your EV from a coal plant (which the vast majority don't, coal use has fallen below 20% in this country), it is still cleaner from a CO2 standpoint because EVs are just that much more efficient. Additionally, it is far easier to make sure that a few power plants are burning cleanly than it is to make sure 200 million cars are. You live in NY, so you have emissions checks. Ohio doesn't bother with that, so cars can pollute however much they want and I get to breathe it all.