This is pretty surprising. What it means is that most owners will not need to replace their batteries in the time that they own the car. In my 'total cost of ownership' models, I've assumed a battery replacement at 100,000 miles, but that appears to not be necessary. This changes the calculation considerably. Not to mention that if the drive train can go 400,000 miles without needing major repair, I can keep the car 2x as long as an ICE, further reducing the cost of owning an electric vehicle.