Car Battery Life: Warning Signs and Ways to Get Help

Do you know how old your car battery is? Here’s how to avoid the surprise of a dead battery.

Illustration of car battery on red background

You may not give your car battery enough thought. Until you have battery problems, that is.

Battery trouble is a leading cause of roadside breakdowns, according to AAA research. Yet most people don’t periodically test their car battery or even think about battery replacement until they actually need it. Because you won’t know the exact number of days in your battery lifespan, a battery on the brink of dying rarely warns you before it fails. This is why getting a simple battery test is so important.

Here’s what makes your car battery tick—and how you can get help predicting when your car battery life is nearing its end.

How does a car battery work?

A car battery creates electricity through a chemical reaction. A series of lead plates contained in cells interact with an electrolyte. The resulting chemical reaction generates electrons, which travel through an outside circuit to create an electric current.

When you turn on your car’s ignition, the electrical charge is released to the ignition system to start the engine. Once the car is running, the battery’s job is done and the chemical process reverses, recharging the battery as you drive. This is battery power.

Car battery types

Animated illustration of two hands holding a digital tablet scrolling through web pages of car batteries

Most cars use flooded lead-acid batteries, but newer models with high electrical loads require an enhanced flooded battery or absorbent glass mat design.
Installing the wrong battery type can impact electrical system performance and battery life. That’s why AAA recommends replacing a battery with the same type that came in the vehicle from the factory. As you would for other types of car care, consult your owner’s manual for more information.

How long do car batteries last?

The average car battery has a life expectancy of three to five years. This is why it’s vital to get your battery checked about every six months. Some people have it checked when they get other maintenance done, such as an oil change and tire rotation. Even if you have a new car, it’s important to be aware of battery life.

Volts matter: Why your vehicle’s battery dies

Over time, lead sulfate crystals form on a battery’s lead plates. When the plate coverage reaches its threshold—typically after three to five years of use—the battery can’t produce enough electricity to start the engine.
There are many things that can impact car battery life:

  • Extreme temperatures, especially heat but cold weather and climate can have an impact.
  • Inactivity for long periods and excessive short trips.
  •  Lack of maintenance, such as letting corrosion build up.
  •  Technical problems, such as electrical issues or a faulty charging system.
  •  Human error, such as storing your key fob too close to the vehicle or leaving accessories plugged into always-on power outlets. Driving habits can also make an impact.

Car battery life and warning signs

Illustration of hand holding a clipboard with report on car battery life

Battery capacity varies from vehicle to vehicle. And while most dying batteries don’t show symptoms, the warning signs you’ll soon need jumper cables and a car battery replacement could include:

  • Car slowly cranks when you’re trying to start it.
  • A grinding, clicking or buzzing sound when you turn on the ignition.
  • Dim headlights, especially when your car is idling.
  • The battery warning light is illuminated.
  • Corrosion, cracks or bulges on your battery.

Bottom line: You don’t have a set number of days for your car battery lifespan. If your car battery is more than three years old, test it twice a year. Testing is free for AAA Members at a local AAA Approved Auto Repair Facility.

AAA Mobile Battery Service

All batteries die, but you don’t have to be stranded when it happens. Contact AAA’s Mobile Battery Service and we’ll come to you to perform a battery and electrical system test. And with the increase in popularity of electric vehicles (EVs), AAA can also service electric vehicle batteries at select locations.

Plus, if you purchase a new AAA battery (which includes a nationwide three-year full replacement warranty), you can see the cost with your AAA Member discount using the Instant Battery Quote.

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