How Long Will A Car's 12-Volt Battery Last?

Car batteries have a finite life span, but regular attention and maintenance can help reduce your odds of being stranded without a charge.

Evan McCausland | 

Sep 29, 2022 | 3 min read

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You might be on top of scheduling oil changes or tire rotations, but when’s the last time you thought about your car’s 12-volt battery? Like most other wear items on your vehicle, automotive batteries have a finite lifespan — and ignoring them could leave you stranded when you least expect it.

THREE TO FIVE, WITH GOOD BEHAVIOR

Battery manufacturers suggest the average lifespan of an auto battery falls anywhere between three and five years — and for good reason. Between powering lights, computers, infotainment systems, electrical accessories and your engine’s starter motor (even on most hybrid-electric vehicles), your little ol’ 12-volt battery has its work cut out.

If that isn’t enough, car batteries are subjected to an incredibly toxic work environment. Batteries don’t like heat or vibrations; both can cause internal damage that reduce a battery’s ability to hold an electric charge. Unfortunately, most car batteries are located under hood, immediately adjacent to an engine which produces — you guessed it — both heat and vibration.

SIGNS THE END IS NIGH

So how can you tell it might be time to replace your battery? For starters, look at it — there’s likely a manufacture date stamped on a label or into the casing. If your battery is over the three-year mark, you might want to bite the bullet and buy a new one, especially if you’re just around the corner from a harsh winter, which can further stress your battery.

Secondly, keep an eye on how your vehicle performs. If you notice dimmer headlights, slow power windows, and perhaps most notably a longer crank time needed to start your engine, it could be a sign of a weakened battery. This is especially true if these symptoms return after using a battery charger.

The best way to precisely know your battery’s health is to stress-test it with a load tester. Although these can be added to your toolbox for well under $20, most auto-parts stores have them on hand and will happily test your battery for free. Better yet, they also may be able to test your vehicle’s alternator, which is responsible for maintaining your battery’s voltage while on the road.

BATTERY HEALTH TIPS

If you want to maximize the life of your new battery, or eke a little more time from your current one, there are some tricks you can incorporate into your driving habits.

Avoid frequent short trips, which don’t allow your alternator to fully charge the battery. Also, avoid using the radio or other accessories for prolonged periods with the engine off.

If possible, park your car indoors, where the battery is less likely to be affected by temperature swings. If you plan on letting your vehicle sit idle for extended periods of time, consider connecting a battery tender or trickle charger to maintain the battery’s charge.

Preventative maintenance, including cleaning corrosion off battery posts and terminals, and periodically checking electrolyte levels on non-maintenance-free batteries, can also help maximize your battery’s performance and extend its life span.

Evan McCausland

Car, truck, train, or bus—if a vehicle has wheels, chances are Evan McCausland is interested in it. More importantly, he’s interested in helping others learn more about cars and trucks, especially when it comes time to make a decision on their next vehicle purchase. For nearly two decades, he’s been fortunate to have the opportunity to do just that, writing for major automotive publications, automotive clubs, and automakers alike.