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Everything You Need to Know About the Battery in Your Car or Truck

Power - by Bryan Veldboom - updated on 10/25/2021

woman in green shirt driving down a road

An auto battery has a limited number of times it can start your vehicle before it needs to be replaced. Most car batteries will last between 500 and 1,000 charging cycles, which works out to a lifespan of between three and five years, depending on driving and weather conditions. While there's no way to make your car battery last forever, you can prolong its life as long as possible by caring for it properly. Today, we'll be discussing some basic vehicle battery maintenance and how to tell when your battery needs replacing.

What Happens When Your Battery's Charge Gets Too Low?

The single most important thing to understand about your battery is that you need to keep it charged up. If you let the charge drop too low, your battery can become irreparably damaged. So, how low are we talking? A typical 12-volt auto battery will have around 12.6 volts when fully charged. It only needs to drop down to around 10.5 volts to be considered fully discharged. If it drops down below that, the battery will become damaged due to excessive sulfation.

Sulfation refers to the formation of lead sulfate crystals on the surface of the battery's lead plates. During a normal cycle, this build up of crystals is only temporary and is reversed when the battery is recharged. Excessively draining a battery, however, allows the soft lead sulfate to crystallize. Once that happens, any crystallized lead sulfate will remain on the battery's plates, throwing off the chemical balance of the battery. This reduces its overall electrical output and shortens the battery's life. If enough of this crystallization is allowed to occur, the battery will no longer be able to provide the amperage necessary to start your engine and will need to be replaced.

How Do I Keep My Car Battery Charged?

Believe it or not, the best thing you can do for your vehicle is drive it. Your battery uses up a lot of energy in starting up your car and your alternator replaces this lost energy when you drive. This recharging process takes around 30 minutes to complete when you're driving at highway speeds. Now, that doesn't mean you have to drive around for an extra half hour every time you start up your car, but you should try to get in a good 30 minute drive at least once a week. This is especially important if you tend to take lots of short trips in which you're constantly starting and stopping your vehicle.

What Are Some Additional Drains on Your Car Battery?

While your driving habits have a big impact on your battery's lifespan, they're not the only factors at work. Extreme weather, corrosion and even the amount of technology you have in your car all put additional stresses on your battery. Read our article entitled "6 Things That Can Drain Your Car Battery" for additional tips on how to prevent your battery from discharging too low.

What is a Battery Charger and Why Do I Need One?

If you don't do a lot of driving or you have a car that you end up storing for the winter season, you might want to consider picking up a battery charger. A charger is a device that provides your battery with current to help keep its charge from getting too low. Read about several different types of chargers.

Regardless of the type of charger you choose, you need to be sure that you don't overcharge your battery. Providing your battery with too much charge can be just as harmful as providing it with too little. When you overcharge a battery, the excessive current cooks the components inside. This can cause corrosion to form on the battery's terminals, which makes your battery far less effective. Excessive overcharging can also damage the battery's plates, causing the chemicals inside to "gas" or causing melting, swelling or cracking of the battery's exterior. If any of those things happen, your battery is no longer safe to use.

When selecting a charger, be sure that it's compatible with both the chemistry and voltage of your battery. Battery maintainers are a great choice because they will shut off automatically once your battery reaches its ideal charge, preventing it from overcharging.

Do Vehicles with Stop-Start Technology Require Special Batteries?

In vehicles with start-stop technology, the system stops the engine when it becomes idle and starts it back up again when the driver takes their foot off the brake pedal. All this extra stopping and starting requires more energy than an ordinary starter battery can handle. If you have such a vehicle, you need to use an AGM (Absorbed Glass Mat) battery in your car or truck.

AGM batteries are equipped to deal with the large number of cycles required in automatic start-stop systems while still providing a stable level of power needed to run things like lights, radios and air conditioning. Learn more about the differences between AGM and flooded batteries.

How Do You Know When a Car Battery Needs Replacing?

If your battery frequently dies or it takes you multiple attempts to start your engine every morning, there's a good chance it needs replacing. You may also notice that the "Check Engine" light turns on. You can also pop the hood and take a look at the battery itself. If you notice a buildup of corrosion on the terminals, that's another sign that your battery is past its prime.

Get Your Battery Installed at Batteries Plus

If you notice any of the issues above, you can either test the battery's voltage using a multimeter or bring it to any Batteries Plus location. Our experts will test your battery, starter and alternator and let you know if you have a problem. Best of all, the test is free. Browse our selection of replacement car and truck batteries online, then stop by one of our stores and have it installed (on most makes and models at most locations).

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