There's no reason to think that batteries won't last the life of a car. In fact, it's looking more and more like the batteries will outlive the usefulness of the car.
https://www.wired.com/story/what-hap...lasts-the-car/
There's already plans for recycling the batteries as they will be extremely valuable due to their contents. The trouble is, there are no batteries yet to recycle. Volkswagen plans to buy back and recycle their own, Redwood minerals has plans to develop a supply chain of used batteries.
I get that the batteries are warrantied for 100,000 miles, but we don't get replacement engines after the warranty ends either, so I'm not sure why that's relevant.