BCI Battery Group Size Chart For Cars: Essential Notes
Some car owners often care about battery performance and price but ignore its size. However, the right dimension is the prerequisite for the device to function correctly and safely.
In other words, understanding the BCI group size or equivalents should be done simultaneously with the different specifications. If you have no idea about this term, scroll down for an explanation.
What Is BCI Car Battery Sizes?
The battery group size consists of a sequence of letters and numbers representing the car battery’s physical dimension.
Meanwhile, BCI stands for Battery Council International, which sets the common standards for battery weight, size, and testing procedures in the US market.
The organization is also responsible for providing guidelines on recycling and storage and encouraging innovation to promote efficiency, safety standards, and sustainable technology. If your items are certified by BCI, feel free to rest assured about their performance.
The BCI battery classification lists more than 130 names for different groups of products.
Based on these data, it is straightforward to consider the suitable vehicles or applications compatible with each battery type. The labels also clarify the terminal positions and assembly format.
How To Choose The Correct Battery?
Essential Factors To Determine The Right Type Of Battery
The two most important factors to consider are the car’s compatibility with the battery in terms of power and the compartment design.
At first, some modern vehicles require more additional amp hours than others, thus working well with high-efficiency and larger battery packs.
The right product should provide enough amperage to start and maintain engines and other modern accessories. If you fail to supply continuous power, the car will not run, especially in colder climates when the engine requires additional force.
Fortunately, it is not difficult to check the specifications. All necessary information is available in the owner’s manual, including recommended battery group and amp hour capacities.
Second, a suitable group should fit the internal construction and the post system. Getting the wrong dimension causes the product to wobble, damaging itself and the vehicle. You may sometimes not connect with battery cables and end up with useless components.
If you cannot find the manual, measure your battery tray to determine the right dimension. Then consult a battery specialist or mechanic to confirm your choice.
Once you have found the BCI group for your vehicle, consider the specifications of each item. Some people mistakenly assume that the physical size affects its amp-hour rate.
That’s not the whole story now! Advanced battery technology has given birth to compact options that operate many times more powerfully than large ones.
What If I Can’t Find The Right Battery For My Group?
In some cases, you may not be able to find the actual size you need for your vehicle because it is out of stock. What should you do in an emergency?
Get a universal holder and tie-down and replace them with your current tray. Then look for a battery that resembles the existing one as much as possible.
Another solution is to learn about recommended equivalents. Though the features are almost the same, you sometimes have to purchase a battery holder as the first solution for a perfect fit.
Regardless of which measure you follow, pay close attention to the specifications and ensure absolute accuracy.
Choose The Best Battery Replacement
Regarding battery replacement, most drivers understand the required specs and FOCUS on comparing battery brands. Durability, performance or price are what matters most.
Nowadays, we have many resources available for good advice. Online customer reviews are the most objective information to reveal real experiences. You may also come across potential problems for your intended products.
Alternatively, you can communicate with experienced mechanics happy to provide good recommendations for your preference.
BCI Equivalents: Cross Reference Battery Size Group Chart With DIN And EN Codes
Passenger Cars
Commercial vehicles make up the majority of battery groups. Its vast range spans many sizes, specifications, and capacities. Some popular options include 24, 27, 34, 35, 49, 65, and 78.
Trucks
Light trucks typically use components in groups 1, 2, 2E, 17HF, and 19L. The choice varies with the number of electronic devices attached to the vehicle.
Heavy trucks are compatible with heavy-duty battery groups like 3, 3EH, 4, 5D, and 7D. These options typically have three cells, while six-cell parts, including 3ET, 4D, 6D, 8D, 2, 29H, and 31, are recommended for vehicles requiring high battery amp-hour capacity.
Motorcycles, Bikes, Or Powersports
Labels for this type of vehicle usually start with CB, GB, YB, Y, G, or C. Some common names for lead-acid batteries include YB14L-A2, 12N24-3, or Y60-N24L.A.
Meanwhile, maintenance-free motorcycles have the initials YTX, GTX, or CTX. You can also refer to gel batteries with categories including YT, CT, GT, GTZ, CTZ, or YTZ.
Hybrid Cars
Electric vehicles often come with three-cell batteries like the CG2H and GC2. Some models may also require 4 or 6 cells, so consider GC8, GC8H, and GC12.
Lawn Mower
U1, U2, or U1R are common in lawnmowers, golf carts, and utility vehicles. You may be surprised to learn that they are considered general-purpose batteries.
Boats, Large RVs
For marine batteries, the group of 24, which are lead-acid parts, come out on top. Some other options worth considering include 4D, 8D, 27, 31, and 34.
Best Car Battery
Will Moore has been driving since he was first allowed behind the wheel of a golf cart. He’s written for several major auto sites including Motor1 since 2020, unraveling the intricacies of auto insurance policies and products for the everyday driver. Will has logged hundreds of hours researching and testing products ranging from child car seats to torque wrenches. After completing a PhD at the University of Missouri, Will moved to North Carolina with his wife, daughter, and two semi-obedient beagles. Will is also Certified by Safe Kids Worldwide as a Child Passenger Safety Technician (#T836339).
New car batteries can cost at least 150, and the best car batteries often run even higher. Many cars will need a battery replacement at some point. Learning about battery maintenance, battery replacement, and the types of car batteries can save time, stress, and money. In the hopes of helping customers find affordable car batteries that stand the test of time, our review team researched some of the most popular options on the market. Whether you need a car battery that performs in cold weather or extreme temperatures, we’ve analyzed a range of high-quality batteries. This guide also offers some tips for battery maintenance and replacement. We did all the research so you don’t have to.
Our Review Standards
To select the car batteries featured in this buyers guide, our team first combed through dozens of resources such as DIY mechanic and auto enthusiast forums, manufacturer and auto battery-specific websites, instruction manuals from manufacturers, and reviews from online retailers. We pay particularly close attention to quality reviews and recommendations that highlight the quality of warranties, customer service support, build quality, materials, and overall reliability. We also factored in the quantity and quality of online retailer reviews from websites such as Amazon, RealTruck, Advance Auto Parts, and more. We looked at factors such as standout customer reviews, prices, meaningful superlatives, and discount shipping eligibility.
Why You Can Trust Us
Since 2020, we have published over 200 auto product reviews in an effort to make shopping for auto products easier. Our team of writers, editors, researchers, and product experts collaborates to thoroughly vet top products. We try to perform in-house testing on real vehicles whenever possible before making our recommendations. When testing is not feasible, however, our aim is to make your life easier by doing all the online research for you and presenting that research in the form of easy-to-read product comparisons and buyers guides, rather than outright recommendations. For more information on our testing methodology and how we evaluate every product, check out our methodology page here.
Best Car Battery: Buyers Guide
Battery Type
There are a number of different car battery technologies out there. Standard lead-acid (SLA) and absorbed glass mat (AGM) batteries are the most common. Lithium-ion batteries are also becoming more common for cars.
- Standard flooded lead acid : This is the most common type of car battery. The battery contains liquid battery acid and will require more maintenance than an AGM or lithium-ion battery. This type of battery is most common in older vehicles (pre-1980).
- Absorbed glass mat : An absorbed glass mat battery is highly vibration-resistant, non-spillable, and maintenance-free. Battery acid is absorbed in fiberglass mats, which prevents leakage or spillage. This type of battery offers a superior lifespan to standard flooded batteries and can handle large power demands. It is the most common type of car battery in modern vehicles.
- Lithium-ion : Lithium-ion batteries can be much smaller and lighter than AGM and SLA batteries. They offer a very fast charging rate and are maintenance-free. This type of battery tends to outlast AGM batteries.
Choose a battery type that matches your existing battery. AGM batteries are the most common type of car battery. If you replace an AGM battery with an SLA battery, your car may not start or function properly.
Group Size
Your car battery rests in a specifically sized battery box. If your replacement battery is too small, it won’t be properly secured. If it is too big, it won’t fit in your vehicle. In addition to battery dimensions (length, width, and height), terminal location is also critical to proper fit.
Fortunately, you won’t need to get out the measuring tape to match battery dimensions. All batteries should have their group size listed somewhere on the label. This is typically a two-digit number. You can also check your owner’s manual, which may list the group size, or try searching Google for your group size based on your vehicle’s make, model, and year.
Below are some common group sizes:
Cold Cranking Amps (CCA)
CCAs refer to a battery’s ability to turn a cold engine. The higher the CCA, the more powerful the battery. As with group size, your current battery’s CCA should be listed somewhere on the battery label.
Each car is engineered with the factory battery CCAs in mind, which is why it’s a good idea to match the CCA of your current battery – rather than attempt to “upgrade” your battery to one with more CCAs, as this can lead to decreased battery life.
Reserve Capacity (RC)
Reserve capacity refers to a battery’s ability to keep essential car accessories powered after a vehicle’s alternator fails. With more and more cars using computers and battery power for essential systems, RC has become an important battery feature.
As with CCA, try to match your new battery’s RC with the original battery. If you choose a new battery with a lower RC, it could fail to properly power your car’s critical systems.
Warranty
Once you’ve found batteries that match the specifications of the one you are replacing, consider batteries with longer warranties. These are guarantees that you won’t have to shell out for a replacement within the warranty period.
Most car batteries come with at least a one-year warranty, but some offer warranties up to three or four years long.
Car Battery Replacement Tips
If you need to replace a dead battery, you can take it to an auto mechanic for diagnosis. A mechanic will have the tools to diagnose and quickly change your car battery. Labor costs for battery replacement can range from about 37 to 47, according to RepairPal. That said, those costs don’t account for the type of battery you’re purchasing.
If you’d prefer to change your own car battery, this is possible for a layperson, though it can be an involved procedure. Specifics may vary from vehicle to vehicle, as battery positioning is not the same for every car. Search for guide videos specific to your vehicle’s make and model or start with our general guide on how to disconnect a car battery.
Whichever type of car you have, there are some tips to keep in mind when performing an at-home car battery replacement.
- Put safety first. Modern AGM and lithium-ion batteries are mostly safe to handle, but SLA batteries can slosh highly corrosive acid that will damage your skin and eyes. Wear proper safety equipment including goggles, long sleeves, and gloves when handling a car battery. It’s also a good idea to keep some baking soda handy, as it can be used to neutralize any spilled battery acid.
- Keep your car’s memory alive. Modern vehicles are highly dependent on computers to operate major and minor systems. When you disconnect your car battery, it can turn off the computer, effectively resetting the onboard computer. This can cause some systems to work improperly until they are reset. Some cars will reset automatically after a few weeks, while others may require hours of diagnostic fiddling to restore. You can prevent this hassle by using a power supply cable to keep your computer powered while you replace the battery.
- Be gentle. Don’t attempt to smash or roughly shove your battery into place. The same goes when attaching the terminal clamps. If your terminal clamps are too tight, use a terminal spreader to widen battery terminals rather than banging on your battery to force them down.
- Recycle. Car battery recycling must be done at specific locations. Check your city website to find guidelines on hazardous waste disposal. Many offer dropoff or pickup services. You can also recycle old batteries at certain stores. Advance Auto Parts and AutoZone both offer battery recycling services. These stores also offer free battery testing.
How Much Should Car Batteries Cost?
Newer car batteries that have higher CCAs and use advanced technology are going to cost more than replacement batteries for older vehicles. While more expensive, these batteries also tend to last much longer, so can be cheaper in the long run.
In general, you can expect to pay anywhere from 150 to 500 for a new car battery. SLA batteries are usually the least expensive, followed by AGM batteries. If you choose a lithium battery, you might pay upward of 450,000.
Depending on the CCA, RC, and group size, the same model battery can vary in price up to 100.
Why Do Car Batteries Go Bad?
Car batteries fail due to multiple factors ranging from neglect to old age. Below are a few examples of what causes batteries to die.
- Temperature : Climate is probably the greatest opponent your car battery will face. Even the best car batteries can struggle to crank in extreme temperatures, so more temperate climates typically mean a battery lasts longer.
- Minimal Use : Having a car sit idle for a few weeks or months will usually result in a dead battery. That’s because it is not utilizing enough of the car’s charging system, which depends on the car running, to recharge.
- Vibrations : If a car battery is not properly secured in the engine bay, vibrations from the vehicle can cause it to deteriorate and shorten battery life.
- Corrosion : Corrosion occurs as chemicals naturally escape from the car battery and mix with air and water in the engine bay. As corrosion accumulates, it can weaken the connection of the battery terminals.
If your car battery failed within two to three years of purchase, check the parts store’s replacement warranty, they may offer a free replacement. For details on how long car batteries last, check out our informational guide.
Shop Group 24 Batteries
A group 27 marine battery measures 11 inches in length, 7.3 inches in width, and 9.3 inches in height. It is slightly larger than a group 24 and is one of the most common AGM marine battery sizes.
The Dakota Lithium 12V 100Ah battery is a more powerful and lightweight replacement for group 27 batteries. Built from lithium iron phosphate technology, the Dakota Lithium 12V 100Ah battery has twice the usable power and half the weight of a group 27 AGM or lead acid battery. The best part is it lasts 5X longer in terms of lifespan, providing exceptional lifetime value. Backed up by a best in class 11 year warranty. This is the original Dakota Lithium battery, battle tested over a decade of adventures in the most extreme of conditions.
If you are looking to cut weight, the ultimate replacement for a group 27 battery is the smaller and more powerful Dakota Lithium Plus 12V 135Ah battery. Even though it is technically a smaller size battery it is a drop in replacement for group 27, 31, or 8D since it has more usable power than even the largest AGM or lead acid marine batteries but in a much smaller case.
The Best Group 31 Marine Battery
A group 31 battery is slightly longer than a battery group size chart 27. Measures 12.8 inches in length, 6.8 inches in width, and 9.3 inches in height. This is the most popular marine battery size for boats that are powering multiple electronics. It is also used widely in the RV industry as a house battery and for solar power.
The ultimate group 31 marine battery is the Dakota Lithium Plus 12V 280Ah battery. With over 6X the usable power of a traditional group 31 AGM battery, the DL 280 is the most energy dense battery available on the market, with 280 Amp Hours of Dakota Lithium energy inside a case designed to hold 100 Ah of lead acid energy. That means a single DL 280 can replace six AGM or lead acid batteries. This incredible energy density allows boats to replace gasoline generators with a smaller and more compact battery bank. It also allows boats to add power hungry upgrades like air conditioning, electric grills, or induction stove tops.
The best part is the DL 280 is a dual purpose battery with both 280 Ah of deep cycle performance PLUS 1,000 CCA of engine cranking power. This gives you the ability to have one battery to both start your engines and run your electronics.
Shop Group 31 Batteries
The Group 34 marine battery is a slightly longer version of the Group 31. It measures 13.5 inches in length, 6.8 inches in width, and 9.3 inches in height. The best lithium upgrade for a group 34 battery is the Dakota Lithium Plus 12V 280Ah battery. This is because of the exceptional energy density. With the power of six group 34 batteries inside a single Dakota Lithium battery.
The Best 8D Marine Battery
8D batteries are the largest marine batteries. They measure 20.75 in in length, 11.13 in in width, and 9.88 in in height. 8D battery group size chart were developed to power large boats, commercial fishing vessels, and RVs and motorhomes. Dakota Lithium first launched an 8D lithium battery as the Dakota Lithium 12V 200Ah battery. With twice the usable power, and 1/2 the weight of an AGM battery. The DL 12V 200Ah became wildly popular for sprinter van builds, RVs, and boats. In 2023 Dakota Lithium launched the DL 12V 280Ah battery, which is 4X the usable power of a 8D lead acid battery in a case that is significantly smaller. This makes the DL 280 the ultimate upgrade with 4X the power, 1/3 the weight, and 5X the lifespan of a traditional 8D battery. Plus 1,000 cold cranking amps of engine starting power.
Tesla Model 3 Battery Replacement Cost
Current Automotive posted the 2020 receipt of one customer’s replacement of a remanufactured 75kWh battery in a Tesla Model 3:
This equates to 180/kWh which is about 31% higher than the Bloomberg cited average of 137/kWh. Since Tesla Model 3s are so new, there is likely very little data on repair costs in the public domain.
However, there is the occasional accident that requires a battery replacement in a Model 3. Based on data we’ve seen for more recent, accident-related replacements, the total amount has come down to 10. 12,000, with 80-90% of that going for the battery itself. However, it is encouraging that the total price has dropped, landing the cost between 133/kWh. 161/kWh. This is more in line with the Bloomberg estimate.
Tesla Model S Battery Replacement Cost
We wrote an article dedicated to Tesla battery replacements, but you can get the summary here.
- In April 2021, FindMyElectric reported that there were a few cases where the price of the batteries cost 12,000 to 15,000.
- A used 2014 Tesla Model S owner reported that a full battery pack replacement would have cost 20,000, including labor, in Dec 2020.
- On Tesla motors club in 2021, there are tworeports of owners of (2012 and 2013) Model S’s being quoted 22k for full battery replacements out of warranty.
VW e-Golf Battery Replacement Cost
A replacement battery for a 2017 to 2018 VW e-Golf is quoted as 23,442.91 by Pignataro VW as of August 2021. Given that the 2017 e-golf battery pack is 35.8 kWh, that equates to 654/kWh, a whopping 477% more expensive than the average 2020 price.
It should not be a surprise that treating your battery nicely can expand its life and delay replacement. Here are some tips on how to give your battery the TLC it needs.
- Avoid extreme high or low battery levels.
- Limit DC fast charging to special occasions.
- Small, frequent charges are better than large, infrequent charges.
- Get your battery to room temperature before charging when possible. Usually this is accomplished by your vehicle automatically once plugged in.
- Park in the shade during warm months to keep your battery cooler.
- A/C and heat use a lot of energy so consider preheating your car while it’s plugged in or using seat warmers.
- Accelerate slowly to increase range.
- Avoid excessive highway speeds.
- Check out your manuals battery maintenance tips.
- Swap your tires for more efficient tires; seasonally appropriate.
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