Circumstantially, the battery can last a very long time; 7 to 9 years is common with a number of earlier (2013)VFs still running original batteries; there will usually only be a surprise warning — when the battery is load tested that it is on the way out. Replacing it then, and not "oh, it'll be fine for a few more months" is better than being stuck in a cold car park late at night. A lot depends not just on the VF's battery charge-discharge management system, but how the car is driven. Repeated short drives in cold weather (winter, especially) where the engine doesn't reach proper and sustained operating temperature; leaving consumers on (radio, a/c, lights etc.) all add up to shortening the battery's service life. Plenty of cars fall into this category of driving unfortunately. My VF recently serviced with 5 year old battery and given excellent health check (AC Delco). Have seen it only once or twice before, tucked cosily away in the back. I regularly run (long!) rings around SW Victoria each and every week (95,000km so far). No wallflower, this car.