“By 2030 there will be a major automotive vendor offering 15 year warranties on EV batteries.”

The world’s largest vendor in EV batteries, CATL is now offering 10 year warranties. https://batteryindustry.tech/catl-starts-delivery-of-ev-batteries-with-600000-miles-warranty-that-can-last-15-years/. Geotab (https://www.geotab.com/blog/ev-battery-health/) has reported that battery degradation has improved from 2.3 to 1.8% degradation. With existing technology that would provide for 75% battery capacity after 15 years 100 x (1-0.018)^15. The learning curve will further increase this as EV volumes ramp up over the next few years, and CATL has already placed 15 year warranties on their roadmap.