Like the other commenter, I've never heard of a battery lease. Just bought it outright.

For what it's worth I had the choice to pay a bit more to get a different Leaf that had a new battery (replacement under warranty). Given that I don't drive much (6 mile commute), I figured a slightly healthier battery is probably not going to be as useful to me, and the car/battery will deteriorate from age before mileage is as much a factor.

I outright bought mine. I'd never heard of battery leasing until your comment, it doesn't appear to be an option in Canada.