There's a lot more to the equation that just the battery. In term of over all pollution they're far better than a gas car. (220g CO2e/km vs 21-25g CO2e/km)
Even if you just paid cash for a car and thus that is sunk pollution we are not counting, not more than 3 years to make up the fuel. If you count the car you already did
One thing I like about Reddit/Fediverse and friends is that when someone discoveries or has the answer, they can throw information in these parts for others to find out!
In the best-case scenario - a system like this can feel almost like a tight encyclopedia!