
If you're having trouble starting your car or if it's been several years since you've replaced your vehicle's power source, it may be time to shop for a new car battery. Auto repair purchases can be intimidating, but knowing how to buy a car battery can take the guesswork out of this important automotive decision.
How to Buy a Car Battery in Five Steps
Your car needs its battery in order to operate. In fact, the battery is what powers the car's starter motor and ignition system. The battery also provides the power for lighting and accessories and gives power to the electrical system of your vehicle when the charging system is not operational.
Since your battery is such an important part of your car, buying the right replacement model is essential.
1. Identify Your Battery
Before you go shopping, you need to identify the type of battery that's currently in your car. The easiest way to find this information is by looking in your owner's manual. However, if you've misplaced your manual, you have a few other options:
- Visit the manufacturer's website to see if they have an owner services department where you can download an electronic manual for your vehicles.
- Visit the car dealership. Even if you don't plan to buy the battery there, you can find out exactly what kind of battery you need from someone in the service department.
- Consult an expert at your favorite local auto parts store. Many parts stores employ knowledgeable individuals who can help you identify your car's battery.
- Examine the battery yourself. To do this, lift up your car's hood. The battery is the rectangular part with cables attached to it. Read the group size off of the label, and also look for specifications like "cold cranking amps" and "reserve capacity."
2. Understand the Terminology
Now that you know what you're shopping for, it's tempting to start comparing battery prices. However, you won't know whether you're comparing like models if you don't have a basic understanding of the terminology used with auto batteries.

- Cold cranking amps (CCA) is the measure of a battery's ability to start your vehicle in cold weather conditions. The size of the battery CCA rating should meet or exceed the car's OEM (original equipment manufacturer) cranking rate.
- Reserve capacity is the number of minutes your car might run using the battery alone should your alternator fail.
- Group size refers to the outside dimensions and placement of power terminals on the battery. Vehicle makes have different group sizes, but you should always go with the group size that's recommended for your car.
3. Write It Down
Buying the right battery for your car is important for safety reasons, so write down everything you know about your battery. This should include the following:
- Vehicle make, model, and year
- Age of battery, if known
- Battery group size
- Battery cold cranking amps
- Battery reserve capacity
4. Start Shopping
When it comes to buying a car battery, you have a lot of shopping options. Be sure to check with more than one source, so you can get the best deal on your new battery. You may find that one retailer offers the same battery at a considerably cheaper price.
Locally, you can find car batteries at the following retailers:
- Auto parts stores like AC Delco, NAPA Auto Parts, and AutoZone
- Big box stores like Walmart and Sears
- Tire and auto repair shops like Firestone, Goodyear, and Pep Boys
- Auto dealerships
In addition, you can buy auto batteries online at the following sites:
5. Don't Forget Installation

Installing a new battery can be dangerous, since car batteries contain very strong acids and can discharge large amounts of electricity. If you're not trained in auto mechanics, you may want to leave the installation to the professionals.
Installation prices vary dramatically. Some places, like auto dealerships and some repair shops, may charge you extra for installation. On the other hand, according to CostHelper.com, some auto parts stores will actually install the battery for free if you buy it from that store. Buying a battery online may be more affordable, but you'll have to pay someone to install it. The cost of installation may be something to consider as you compare options.
Helpful Tips
Keep these tips in mind as you shop for your new vehicle battery:
- If you live in a cold climate, it is best to get a car battery with a high CCA rating. This is because a sluggish, chilled engine requires more power to start it up.
- Buy a car battery with the longest reserve capacity possible, since you may need it in emergency situations when your vehicle has stalled or will not start.
- Do not buy a car battery that has been on the store shelf for more than six months. You can check the date by looking at the label printed on the battery. The date is defined by a two-digit code with one number and one letter. For instance, "A" would be January, "B" February, etc. The number following it shows the last digit of the year it was made.
- Check out the battery's warranty. No matter how long the warranty is, be sure to ask about the free replacement period. If the battery fails after this date, you will only get a pro-rated credit towards your new battery.
Do Your Homework
Now that you know how to buy a car battery, you can shop with confidence. As with any car-related purchase, be sure to do your homework and ask lots of questions. As an educated consumer, you're far more likely to get a great deal on the very best battery for your car.