The day your car engine stops running is not the best time to buy a new car battery. However, our research shows that most people do exactly that.
Car batteries age and wear out through exposure to heat and repeated charging and discharging, and will probably need to be replaced once or twice in the life of the car. A dead battery is a real headache, especially if you can’t find a jumper cable or have to wait for roadside assistance.
Also, paying attention to the condition and lifespan of the battery will help you know when it is time to replace it before it runs out.
Types of Car Batteries
Immersion Lead Acid Battery
In conventional automotive batteries, lead plates are immersed in an electrolyte to obtain the electrolyte needed for the electrochemical reaction that produces energy. Lead-acid batteries, also called liquid electrolyte batteries, physically immerse lead plates in sulfuric acid. These are the most common and affordable type of car battery. However, there are some disadvantages. The main ones are that they need to be filled with water from time to time, they can only be mounted vertically, and they should not be installed in tight spaces because of the danger of hydrogen loss. It is important to note that cars originally equipped with immersion batteries can usually be converted to AGM, but not vice versa; modern cars with Stop-Start technology are designed to use AGM or EFB batteries.
Absorbent Glass Mat
AGM (absorbent glass mat) batteries are a modified version of lead-acid batteries originally designed for aircraft. Since the main components are lead and electrolyte, the chemical reactions are almost identical. However, the fiberglass mats between the plates carry the electrolyte instead of soaking the lead in liquid. The result is a more efficient, spill-free battery. They are also more resistant to shock and vibration, withstand lower temperatures, and achieve deeper cycles than conventional batteries. The only drawbacks are that they are generally more expensive than other batteries and require a dedicated charger.
Enhanced water-cooled batteries
The enhanced flood battery is another common type. What makes them essentially different from conventional flooded batteries is their improved recharging and deep cycling capabilities. As a unit that fills the gap between flooded lead-acid and AGM batteries, it can be appreciated in many ways: the AGM battery is intended for heavy-duty vehicles, while the latter is often used in smaller vehicles equipped with Stop-Start technology. Nevertheless, in most cases it is possible to switch from an EFB to an AGM battery. However, vehicles designed to run on AGM batteries should not be switched to EFB.
Below are some tips for getting the best battery.
Check under the hood
Be proactive.
By paying attention to battery maintenance and knowing when to replace the battery, you can choose to replace it at your convenience – by doing research and setting a convenient schedule.
Test batteries annually.
Inspections should be part of a homeowner’s routine maintenance, but it is especially important to check before going on a long drive.
According to AAA, car batteries typically last three to five years, ranging from more than 58 months in the northernmost part of the United States to less than 41 months in the southernmost part.
Most car batteries today are “maintenance free,” but it is recommended that you have your battery inspected annually at a mechanic’s shop, usually every two years for those living in warmer climates and four years for those living in colder climates. This test checks the battery’s ability to maintain voltage during use, and the results will inform you when it is time to purchase a new battery.
The age of the battery is also a good indicator to consider replacing it. The date can be found on a sticker on the top or side of the battery; for batteries manufactured in October 2024, the numeric code is 10/21 and the alphanumeric code is K-1.” The “A” represents January, “B” represents February, … (the “I” is omitted).
Batteries must be matched to your car and driving needs
Car batteries come in a variety of sizes. The best performing ones we have tested vary considerably by year and size. Therefore, we cannot simply make recommendations by brand or model. This also means that you should not assume that you will get the same results if you purchase the same model as the battery you are replacing.
Be sure to get the correct size and position terminals (or type) for your vehicle. Refer to the owner’s manual or store fitting guide when making your purchase.
In some cases, replacing the AGM battery with a conventional liquid battery can help it last longer in hot climates, but it is best to consult a mechanic first. To accommodate the increasing number of electrical components, many vehicles are equipped with AGM batteries, and charging systems can be configured specifically for AGM batteries.
Make sure it is a new battery
Batteries lose strength over time, even when stored. For optimal performance, purchase batteries that are less than 6 months old; 3 months is even better. In most cases, you will find the shipping code on the case. Some use letters for the month (“A” for January) and numbers for the year (“1” for 2024), while others use numbers to indicate the date.
Recycle old batteries.
The toxic lead and acid in batteries can be easily recycled, and most retailers will dispose of old batteries. If you store for a new battery, you will probably have to pay a surcharge, which will be refunded if you return the old battery.
Warranty Comparison
It is important to choose the longest possible free battery replacement period. Battery warranties are represented by two numbers: a free replacement period and a proportional period during which only a partial refund is possible. For example, the code 24/84 indicates a free replacement period of 24 months and a proportional warranty of 84 months. However, the refundable amount usually decreases much faster when it comes to the prorated period.
Please note that the warranty may be voided if there are signs of neglect, such as low water levels or poor installation. The same is true for heavy-duty applications such as high-end car audio and marine applications, if the battery is not a recommended battery.
Finding Just the Right Size
Battery sizes vary. It is important to select the appropriate one for fit and adequate power. If the terminals are not properly positioned, the car’s cables may not reach the battery or be properly secured. Refer to the owner’s manual or store installation guide. Many dealers will install the battery for free.
Size 24/24F (top terminal): Fits many Acura, Honda, Infiniti, Lexus, Nissan, and Toyota vehicles.
Size 34/78 (dual terminal): fits many large Chrysler vehicles and many 1996-2000 GM pickups, SUVs, mid-size and large sedans.
Size 35 (upper terminal): fits most Japanese brands, including many late-model Honda, Nissan, Subaru, and Toyota vehicles.
Size 47 (H5) (top terminal): Fits many Buick, Chevrolet, Fiat, and Volkswagen models.
Size 48 (H6) (top terminal): Fits many European and U.S. models of Audi, BMW, Buick, Cadillac, Chevrolet, GMC, Jeep, Mercedes-Benz, Mini, Volkswagen, and Volvo.
Size 49 (H8) (upper terminal): Fits many European and Asian vehicles including Audi, BMW, Hyundai, and Mercedes-Benz.
Size 51R (upper limit): Fits many Japanese cars such as Honda, Mazda, and Nissan.
Size 65 (top terminal): Fits Ford or Mercury large cars, trucks, and sport utility vehicles.
Size 75 (side terminal): Fits General Motors medium cars, compact cars, and some Chrysler vehicles.
Cold Cranking Amperage (CCA) is an indicator of the battery’s ability to start the engine in very cold weather. Using a freezer to replicate winter conditions, the battery is cooled to 0°F and evaluated on its performance. Our CCA test is based on more realistic charge voltage and amperage requirements than typical manufacturer tests, and we believe our results indicate the relative starting power of each battery, regardless of manufacturer claims.
Pack Size
The group size of a battery is the physical size of the battery and the location of its terminals. For example, a 24F pack battery will fit many Honda, Toyota, and Nissan vehicles, but not necessarily American or European vehicles. If you are unsure if your car’s battery compartment will accommodate a certain size bank, you can use an online compatibility checker. You can also check your owner’s manual to see which battery pack size is suitable.
Date of manufacture
Batteries lose power over time, so you want to buy the freshest batteries possible. Some battery manufacturers print a letter and number code on the battery corresponding to the month and year of manufacture, while some brands print the date of manufacture. If possible, check this code before purchasing and try to get a model that was produced within the last six months.
Tips and Tricks
After decades of doing this, you will have a knack for choosing and using the right products. This is the case with us and car batteries. Here is what we have learned so far to help bridge this information gap.
If your car’s electrical system is set up for AGM batteries and you need to replace the original battery, you must use this type of battery.
As before, if the car’s electrical system is set up for a wet battery, the AGM battery will not perform to its full potential.
Use a mixture of baking soda and water on a toothbrush to keep the battery terminals clean. After cleaning, rinse with water and dry thoroughly. Doing so will reduce the rate of corrosion.
If you usually drive on bumpy roads, secure the battery in place. The greater the vibration of the battery, the more likely it is to suffer internal destruction due to short circuits.
Reserve capacity
Reserve capacity is an indication of how long the battery can operate the vehicle in the event of a charging system (alternator, stator, rotor) failure. It is also an indicator of the length of time that the vehicle would not need to be restarted if the vehicle is accidentally started with the lights on. To measure reserve capacity, our engineers measure the time it takes for a fully charged battery to discharge to 10.5 volts, which is considered a complete discharge. At this level, the car will not be able to start without a crash restart; we consider 1.5 hours of power to be average. The highest rated models can provide much more than two hours of power.
Battery life
Battery life is measured by discharging and recharging each battery approximately 3,000 times at a test temperature of approximately 167°F for 15 weeks or until performance reaches acceptable levels. This simulates high temperature conditions in the vehicle during the summer, the hottest time of the year for batteries. Frequent high temperatures are very harsh on batteries, causing the plates to corrode and the electrolyte needed for power to evaporate more quickly. Long life is especially important for frequent short trips with little time to recharge. The higher the score, the longer the battery will remain reliable.
Car Battery Buying Guide 2024 | Video Explanation
Car battery | Infographics
Frequently Asked Questions
You have a question. The reader has the answer.
Q. How much does a car battery usually cost?
A. Car battery prices range from $100 to $350. The amount you pay depends on the brand and type of battery you choose. In most cases, regular lead-acid batteries are closer to the $100 range, while AGM batteries tend to be more expensive.
Q. What should I pay attention to?
A. Two things to keep in mind are the type of battery and the classification group. Older vehicle models require lead-acid batteries, while newer applications often require AGM batteries. We want to match the group number because it has to do with the physical dimensions and determines not only the size, but also the location and type of terminals present.
Q: What is a CCA?
A: CCA stands for “cold crank amperage. This basically indicates the amperage that a battery can supply continuously for 30 seconds at 0 degrees Fahrenheit. Most applications require 650 to 800 CCA, but more than that is rarely a bad thing. Another thing to consider is reserve capacity, which basically indicates how long the battery can power a vehicle without the engine running.
Q: Is it possible to replace a regular battery with an AGM battery?
A: There are many reasons to change to an AGM battery, and you are free to do so. It is always wise to read the application for any nuances that may cause problems, but as long as you choose the correct group number, you can usually replace it right away.
Q: How long do car batteries last?
A: The life of a car battery is usually around 3-4 years. However, if you purchase a reliable car manufacturer’s battery, it may last longer. A good battery typically lasts 5-10 years.
Our Evaluation
We have compiled a list of the best batteries on the market. Reliability, performance, and niche applications are proof of this. Ever Start Batteries have also proven that they can move car owners across the country on a budget.
Let us know what you consider the best battery brand.
Hi, I am David Bailey a dedicated writer from Linden Bridge School with a degree in mechanical engineering and a degree in marketing. I strive to simplify complex subjects and like to explain complex and technical matters in an easy-to-understand manner. Read More Here
