If the maintenance costs are low enough. Replacing battery packs is not going to be cheap. It costs about $3000 USD to replace the battery pack in a Prius (I assume all electric cars will cost more). Generally the pack has to be replaced between 5 and 10 years depending on use.
Not sure why you were downvoted here. This is my exact concern. Batteries don't last forever, and they're expensive to refurbish or (more common, I assume) replace at the sizes necessary for an electric car.
