1 year ago I bought a Smart 453 EZ 12/15 with just under 19,000km and a young smart warranty. Today with 24,000km battery is defective. I always switch off start-stop automatic, so it is never used. Is it normal that the battery is defective after just over 3 years? With the Smart, 12km is driven to work 5 times a week and back. I still have a young smart guarantee. Can I hope for culanz? Or should I just get a new battery