Buying a Car Battery: A Consumer’s Guide

How to Buy a Car Battery Without Overpaying

When it comes to buying a car battery, I don’t mess around. I’ve seen too many people overpay for a battery with a mediocre warranty or, worse, buy the wrong size and have to deal with the hassle of returning it. If you want to get the best deal without getting scammed, here’s exactly what you need to know before you buy a car battery.

Tip 1: Don’t Get Hung Up On Battery Brand

The truth is, the brand of a car battery doesn’t matter as much as the price and warranty. That’s because only three major manufacturers in the U.S. make nearly all car batteries, regardless of the label. Auto parts stores come up with their own brand names, like Duralast (AutoZone), EverStart (Walmart), Duracell, and SureStart (O’Reilly).

• Johnson Controls (Clarios) – Makes batteries for Optima, Duralast, Interstate, EverStart (Walmart), DieHard, and many others.
• East Penn Manufacturing – Produces batteries under the Duracell, Deka, and some Napa brands.
• Exide Technologies – Manufactures Exide-branded batteries and some private-label brands.

Each seller buys car batteries from multiple suppliers. Here’s why: No seller wants to pay to ship 40-lb. lead batteries nationwide. They buy their batteries for each store from the nearest battery manufacturing facility or distribution center.

Johnson Controls (Clarios) has 16 U.S. manufacturing facilities
East Penn has 13 manufacturing facilities
Exide Technologies has three U.S. manufacturing facilities

If you hear that Autozone, for example, buys all its batteries from East Penn, don’t believe it. They’ll buy from multiple supplies, including those with the closest distribution center. They’ll pay each manufacturer to private label the batteries with their proprietary brand.

Step 1: Find Your Car Battery Group Size

Car batteries aren’t one-size-fits-all. Every vehicle requires a specific group size, which dictates the battery’s height, width, depth, and terminal placement. Get this wrong, and you’ll end up with a battery that won’t fit or connect properly.

Most auto parts websites have a battery finder tool, but you can also check your owner’s manual. If you’re still unsure, take a look at the label on your current battery before buying a car battery.

Step 2: Know The Type Of Battery Your Car Requires

When buying a car battery, your first step should include checking your owner’s manual for the battery type and specifications. If you can’t find the specifications there, check with the battery seller. But make sure you install the recommended type

• Most older vehicles require a standard starting, lighting, ignition (SLI) flooded lead acid battery.
• Newer vehicles with start/stop technology will use an Enhanced Flooded Battery (EFB) or an Absorbed Glass Mat (AGM) battery.

Replacing the original battery with the same type is critical. If your vehicle has a start/stop system, you MUST replace the battery with the same type, even if you don’t use the start/stop system. Here’s why: The charging system is designed around the type of battery.

Spiral wound cell versus flat plate technology

EFB and AGM batteries require a different charging routine than SLI batteries. They like to be charged at a lower voltage and longer. So, if you decide to cheap out and install an SLI flooded battery instead of an EFM or AGM, your SLI battery will be dead within a few months because it will be continually undercharged and sulfated.

Likewise, I don’t recommend installing an AGM battery in a vehicle designed for a flooded SLI battery. Older vehicles charge at a higher voltage, which can shorten the life of an AGM battery.

Step 2: Cold Cranking Amps (CCA) Matter

The number one mistake people make when they buy a car battery is ignoring the Cold Cranking Amps (CCA) rating. This number tells you how well the battery will start your car in cold weather.

Check your owner’s manual for the recommended CCA rating. If it’s not listed, look at your current battery’s label. Buying a battery with too low a CCA rating can leave you stranded in winter. On the other hand, going too high won’t give you any extra benefit—it just costs more.

Step 4: The Warranty Matters

When it comes to car battery warranties, the length and terms of the warranty matter. In general, the longer the warranty, the better the battery. Here are the three things to check out:

1) Warranty length— Car batteries used to carry warranties as long as five years. Now, in 2025, the standard warranty length is just three years.

2) Over-the-counter exchange versus pro-rating— Some battery warranties will have stepped coverage where the battery will be replaced free for a certain period of time (usually 1 year). If it fails after that, you’ll get a replacement buy you’ll have to pay a pro-rated amount for the months you’ve used the battery. For example; if the battery has a three year warranty and it fails at the end of the second year, you’ll have to pay 2/3 of the cost of the replacement battery.

Step 5: Where to Buy a Car Battery for the Best Deal

After years of research, I can tell you that the best places to buy a car battery are big-box stores and wholesale clubs. Here’s why:

Costco
Sam’s Club
Walmart

Where NOT to Buy a Car Battery

• Auto Parts Stores—If you want to save money, avoid auto parts stores unless you have an online discount code. They tend to charge way more than big-box retailers, even though they’re selling the exact same batteries made by the same manufacturers.

• Battery Stores— Stores like Batteries Plus tend to charge far more than the big box stores.

What should you look for in a car replacement battery?

Simple: Type (SLI, EFB, or AGM), CCA, Warranty and price.

©, 2022 Rick Muscoplat