Lots of places will say an average car battery's life is somewhere around 3-5 years. It is highly dependent on weather. Here where there are regularly long span

Lots of places will say an average car battery's life is somewhere around 3-5 years. It is highly dependent on weather. Here where there are regularly long spans of 100F+ days, a battery will have done pretty good to make it five years; many die in 3-4. Same in very cold climates. If you're in a place with good weather all the time they'll last considerably longer.