We wish car batteries could talk and tell us when they're going to die, but sadly they can't. Your car battery is vital and allows your vehicle to start and function. It's important to understand the conditions of your battery and the lifecycle on that battery.
With the advancements in technology we enjoy today, most people will find that there is at least one or two batteries on their person at all times. This familiarity with batteries can be used to eliminate confusion about car batteries and assist in quelling fears of the large battery lurking under the hood. But first, let's define what we are referring to by "car battery".
This article does not address the longevity or operation of any hybrid or electric drive system battery, but most hybrid vehicles still need a 12-volt battery for starting the combustion engine. For clarification, the car battery is a large rectangular battery that sits under the hood, in the trunk, or under a seat, depending on which make and model you are servicing. They are typically rated at 12-volts, and the amperage is listed on the top. They are large because they must generate a large amount of electrical current to start the engine, and they may be red, black, gray, yellow, or white in color, black being the most prominent color used. The battery used in your vehicle may have two metal posts that connect to battery cables, or the battery cables may bolt onto the side of the battery.
Also called the service battery, the car battery supplies electrical power to the vehicle when starting, and provides a short supply of power to the vehicle if there is an interruption in charging while the engine is turned on. It will also allow you to use electronic systems in the vehicle while the engine is not running, but remember, the battery is only charging when the gasoline or diesel engine is running. Lastly, some utility and heavy-duty vehicles, will use up to four batteries, while standard vehicles tend to need only one.
Understanding the life-cycle of a 12-volt battery
The life-cycle of a battery refers to the useful life of a battery, and is affected by a few different variables.
The average distance the car will travel in a trip
How often the vehicle is driven
Amount of power demanded from the battery
Proper battery size for the vehicle
Amount of regular maintenance the starting and charging system receives
If the battery is frequently removed, jump started, or used to jump start other vehicles
Average outside temperature where the vehicle is operated
These all factor into the longevity of a car battery, but batteries do inexplicably fail -even in optimal operating conditions.
On average, it is safe to assume a three or four-year lifespan for your battery, but battery life-cycles increase and decrease with the factors listed above. Most car batteries these days come equipped with a sticker or stamp on the face that will tell you the month and year the battery was made.
Signs of Car Battery Failure
Leaving your car sitting in the garage will deteriorate your car battery just as driving it every single day. Some car batteries will show signs of weakening, such as a slow crank when starting your vehicle, but more modern batteries may show no signs at all.
Many batteries will show no signs of failure and simply die one day, possibly leaving you in a bind. If your battery does show signs of failure, it could range from a slow crank when starting your vehicle to electrical issues with your car.
Battery corrosion or acid leakage is also a sign of failure for car batteries. Take a look at your battery's warranty to get a good idea of life - they usually come with a 1 to 3-year warranty, which is a sign of how long your battery is expected to last by the manufacturer.
Cost and Upkeep of a Car Battery
According to RepairPal, the average battery will run between $149 to $202 on average(including a quality battery and professional installation). We recommend a high-quality battery to ensure a longer life and a safer replacement for the more computerized vehicles on the road. You should keep your battery in good shape and inspect it often to ensure a full life.
Cleaning the battery terminals is a simple DIY anyone can do. It is recommended in your owner's manual how often the battery terminals should be inspected, but keep in mind any time the battery seems low that the battery terminals (where the battery cables connect to the battery) may be corroded. This is extremely common, and has led to many needless battery changes. The best part, battery terminal exterior corrosion is something a simple cleaning can address. Here's how:
Safety first! Remember to wear gloves and goggles.
Carefully disconnect the battery, negative first and then positive, making sure no metallic items are connecting a battery terminal to anything else. Especially the other battery terminal.
Mix a solution of 1 cup of hot water with 1 tablespoon of baking soda. This will neutralize the low Ph of battery acid, and penetrate the built-up corrosion for complete removal.
Dip a toothbrush in the solution and scrub the battery posts, inside the battery terminals, and anywhere which may be covered in white corrosion.
Reattach the battery terminals, and charge the battery if needed.
If the battery is still not performing properly, have it tested and replace as necessary.
About the Author
Kimberlea Buczeke is an automotive expert at RepairPal, the leading online source of auto repair resources and estimates. With many ASE Master certified mechanics on staff who have decades of experience, RepairPal knows all the fine points of car repair.
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