This isn’t terribly surprising to me, as electric vehicle
battery packs are often provided with 8-year warranties, and there is a rule of
thumb that the lifespan of equipment normally exceeds its warranty. (Otherwise,
the manufacturer would end up replacing everyone’s equipment.) Still, it’s good
to hear that someone has tested Tesla Roadster Battery Banks and they are
projected to retain 80–85% of the initial full charge after 100,000 miles, much
better than Tesla initially claimed.