How long to batteries last? A quick google search shows that average age of a car in USA is ~12 years... oldtimers and crashed newish cars skew that number awa

How long to batteries last? A quick google search shows that average age of a car in USA is ~12 years... oldtimers and crashed newish cars skew that number away from the median, but generally batteries will lose capacity way sooner than that, and replacement is currently either very expensive or even impossible in some models.