How Long Car Batteries Last & How to Maximize Their Life

• Standard car batteries last around 3–5 years. Electric vehicle batteries have a lifespan of around 12–15 years.
• Heat, repeated short drives, vibrations, and leaving lights on can all drain power from your battery and shorten its lifespan.
• Signs that your battery is going bad are difficulty starting your vehicle, dim lights, and a rotten egg odor.
• ​Maintain your battery by going on drives that are longer than 20 minutes and scrubbing corrosion off the terminals with a wire brush.

Average Battery Lifespan

Car batteries last around 3–5 years. Car batteries are responsible for starting your engine and powering the electrical systems in your vehicle, and every time you run the engine, the battery’s internal components degrade a little bit. While most batteries start losing efficiency after 3 years, their actual lifespan depends on how often you drive and how well you take care of them.

What shortens the life of a car battery?

Heat Warm temperatures speed up the process that generates power inside the battery, but they also make the internal components deteriorate faster. On a hot sunny day, temperatures can get up to 200 °F (93 °C) under your hood and make your battery lose its charge.

Vibrations Normally, batteries sit tightly in a tray under your hood. If your car battery is loose and moves around when you drive, then the vibrations can break down its internal components. Each time the battery shifts or rattles, its lifespan shortens.

Inactivity Your vehicle draws electricity from your battery to keep the clock running, save radio presets, and keep alarms activated even when it’s not running. If you leave your vehicle parked and don’t take it out on a drive, the battery will slowly drain without getting recharged. Without driving, a car battery usually maintains a charge for 3–4 weeks.​​ If you regularly drive your vehicle but it dies after being parked for a few days, there may be a “parasitic draw” in your electrical system, which means there could be crossed wires or a malfunctioning part. Since these issues are tough to diagnose on your own, have a mechanic inspect your vehicle.

Using power without starting the engine When your engine is running, a part called the alternator takes power from your engine to charge your battery. If you turn on your radio, accidentally leave on a dome light, or keep your headlights on without running the engine, the power draws straight from the battery without getting replenished. Even leaving your key in the ignition can drain the charge from your battery.

Repeated short trips When you drive your vehicle for less than 20 minutes, your battery uses more power than it’s able to recharge. If you don’t take a longer trip every so often, your battery will slowly drain and lose its charge.

Overcharging Some after-market battery chargers don’t automatically shut off when the battery is fully charged. If additional power continues running through the battery, it starts to degrade the internal components and shortens the lifespan. A damaged or faulty component in your vehicle’s charging system, such as the regulator or alternator, could also be the culprit for overcharging your battery.

Signs Your Battery is Going Bad

Difficulty starting your vehicle If the engine makes a repeated clicking sound when you turn the key, it may be a sign that the battery doesn’t have enough power to start your engine. If you don’t hear any noise when you turn your key, then your battery already lost all its juice.

Dimmed lights Try turning on both your interior lights and headlights to see how they look. Since your battery powers the light systems, a bad battery will make the lights dimmer than they normally would look. If none of your lights turn on, then your battery has already died.

Corrosion on the battery terminals Find your battery under the hood near one of the front corners of the engine bay. Check the 2 metal terminals on top of your battery to see if they have any white built-up or corrosion around them. Since corrosion prevents the battery from making good contact with the terminal, your vehicle won’t get a proper charge until they’re cleaned.

Rotten egg smell Normally, your battery will run without any odors. If you have an old battery, hydrogen sulfide may leak out and create a foul odor that’s similar to rotten eggs.

Maintaining Your Battery

Drive your car on longer trips. When you drive your car, try to take it out for at least 20 minutes or longer so the battery recharges. It’s still okay if you still make shorter trips occasionally as long as you balance it out with a long drive later on. If you left your car parked for 2–3 weeks without driving it, take it out for an hour-long drive to maintain the battery.

Park in a shaded area. Since heat makes your battery degrade faster, look for a parking spot underneath a tree or covered parking spot. If possible, keep your car in a garage to keep your battery protected from the elements and sudden temperature changes.

Clean your battery terminals. Disconnect your battery from your vehicle and scrape off as much corrosion as you can with a plastic scraper or wire brush. Then, apply a mixture of baking soda and water to the battery terminals to clean them. Corrosion on the terminals may cause problems that are similar to a dead battery. After you clean the terminals, reconnect them to your vehicle to see if it works properly.

Clamp down your battery. If your battery slides around, get a battery clamp for your make and model. Secure the metal bolts in the holes in the sides of the battery tray. Slide the top of the clamp onto the bolts and push it tight against the top of your battery. Then, screw the wingnuts on the top of the bolts to secure the battery clamp. If your battery is the proper size for your vehicle, it will already fit tightly into its tray under the hood.

Connect your battery to a maintainer between drives. A maintainer is an electronic device that recharges your car battery at home. Plug in your maintainer to a wall outlet. Attach the red cord to the positive terminal and the black cord to the negative terminal. Turn on your maintainer so the battery doesn’t degrade. If your battery is already low, use a maintainer that has a stronger charging current to help recharge it.

How long does an electric car battery last?

Electric vehicle (EV) batteries last for about 12–15 years. EV batteries are lithium-ion, so they last longer than standard car batteries. In a moderate climate, the battery in your electric vehicle will function properly for up to 15 years. If you live somewhere with extreme heat or cold, then expect your battery to last around 8–12 years instead. Many EV manufacturers have warranties that their batteries will last at least 8 years or 100,000 mi (160,000 km).