Choosing between different battery sizes can be confusing. What’s the best choice for your car? Group 27 vs. Group 31 batteries may look alike, but there are key differences to consider when making a selection. Know what you need and find out more about these two power sources with us!
Table of Contents
Group 27 Quick Overview
Group 27 batteries are incredibly versatile and powerful. Measuring 12.1 inches long, 6.8 inches wide, and 8.8 inches tall, they come in a range of 54 to 70 pounds depending upon internal design specifications – with capacities ranging from 66Ah up through 110Ah! These AGM lead-acid options boast CCA readings between 600 – 1000 while providing 140–220 minutes RC (reserve capacity).
Popularized largely by automotive applications that require high power but small size, group 27 batteries can easily be found used for both hybrid/electric vehicles as well as those with performance engines the subtypes Group 27F and Group 27H fall under its umbrella alongside traditional Group 27’s too, making it all even more popular across multiple industries alike!
Group 31 Quick Overview
Group 31 batteries are some of the largest lead-acid, or AGM, varieties out there. Boasting dimensions that can range from 13 inches in length, 6.8 inches wide, and 9.4 inches tall, their weight is an impressive 25 to 85 pounds! Not only that, but they have a capacity of 20 hours, a CCA rating between 750 and 1250, and a RC value up to 250 minutes, making them very powerful too.
The many uses for Group 31 include off grid solar power systems, electric vehicles like golf carts or other personal transport solutions, and reliable UPS back-ups too! Depending on your needs, it may be found in deep cycle designs or dual-purpose designs. Whatever your choice, though, this battery packs a serious punch with ample satisfaction guaranteed every time!
Group 27 vs Group 31 Battery
Group 31 and Group 27 batteries may look similar due to their applications, but they have a few differences that are important.
Comparison chart
| Group 27 | Group 31 | |
|---|---|---|
| Dimensions | 12.1 x 6.8 x 8.8 inches | 13 x 6.8 x 9.4 inches |
| Weight | 54-70 pounds | 25-85 pounds |
| RC | 140 to 220 minutes | 150 to 250 minutes |
| CCA | 600-1000 | 750-1250 |
| Capacity | 18h | 20h |
Dimensions
First, let’s take dimensions: the Group 31 is slightly bigger than the Group 27—by an inch or so in some cases, which could make all the difference if you need your battery to fit snugly.
Weight
Both of these car battery types also weigh quite a bit; typically 25–85 pounds for group 31, whereas group 27 weighs 54–70 pounds on average.
Terminal positions
Not only this, even though both offer terminal positions with positive terminal on the right (if viewed from the front), there can still be variance in placement depending on model choice.
RC Rating
Group 31 and Group 27 are two types of batteries. The RC rating for the former is 150-250 minutes, which makes it able to supply power longer than the latter with its 140-220 minute range. It follows that if you need a battery to provide power consistently over an extended period, then choosing one from Group 31 would be your best option!
CCA Rating
The CCA rating measures the battery’s ability to start an engine in cold weather. Group 31 is still a winner in this category, with a CCA rating of 750–1250, while Group 27 has a CCA rating of 600–1000.
Capacity
Group 31 has greater capacity than Group 27 – an advantage of 20 h, compared to the 18 h that can fit in a battery from Group 27! This is ideal for deep cycle applications as it means more power is stored up and ready just when needed.
Wondering what the differences between deep cycle and starting batteries are? Check out the guide to find out.
Group 27 vs Group 31 - Which Group Size Is Better?
Do you want the best battery performance? Group 31 is your answer! It has greater reserve capacity, cold cranking amps, and overall capacity than Group 27. That means it can give power for longer periods of time and start an engine even in colder weather.
Plus, with its higher charge storage capability—it’s perfect for deep-cycle applications that need ample power supply. But before choosing a group size, consider all requirements as well, so you get exactly what suits your needs to a tee, especially the measurements!
Best Group 27 Battery Models
Optima Batteries 8037-127 D27F YellowTop
The Optima Batteries 8037-127 D27F YellowTop (on Amazon) is our number one pick in Group 27 batteries. This dual-purpose battery works both as a deep-cycle and a starter, providing reliable power output on demand!
Using the patented SpiralCell Technology from Optima, this impressive electrochemical setup offers three times improved rechargeability compared to traditional technology of its kind – thanks again to decreased internal resistance promoting an efficient energy transfer rate during charging cycles. Talk about performance you can trust for years!
Technical Features:
- Dimensions: 12.9 x 6.8 x 9.4 inches.
- Weight: 51.3 pounds.
- Capacity: 66 ampere-hours.
- Reserve capacity: 140 minutes.
- Cold cranking amps: 830.
- Cranking amps: 1025.
- Nominal voltage: 12 volts.
Banshee D27M 8027-127
The Banshee D27M 8027-127 (on Amazon) is highly recommended as one of the best Group 27 batteries for your use. This marine battery offers remarkable recharge capabilities and weathers deep charges with ease. It’s a direct replacement for Optima models, crafted from only the latest raw materials available today to ensure superior performance that won’t let you down! What else does it have? A built-in hydrometer gives you precise details about its current condition – helpful in an emergency scenario or otherwise! From boating trips to everyday errands, this rugged yet powerful battery will be at your side no matter what!
Technical Features:
- Dimensions: 12.2 x 6.8 x 8.9 inches.
- Weight: 49 pounds.
- Capacity: 77 ampere-hours.
- Reserve capacity: 114 minutes.
- Cold cranking amps: 800.
- Cranking amps: 1000.
- Nominal voltage: 12 volts.
Best Group 31 Battery Models
Optima Batteries 8052-161 D31M BlueTop
Our choice is the Optima Batteries 8052-161 D31M BlueTop (on Amazon)! It’s a high-oomph battery, boasting illustrious starting power and tremendous deep cycling ability. The AGM design of this dual purpose product keeps any acid spills at bay, while its pure virgin lead plates boost surface area for ideal recycling every time! Don’t just take our word for it – get your hands on one today to see why we deem this Group 31 model a top choice.
Technical Features:
- Dimensions: 13.8 x 6.9 x 9.4 inches.
- Weight: 77.8 pounds.
- Capacity: 100 ampere-hours.
- Reserve capacity: 200 minutes.
- Cold cranking amps: 1150.
- Cranking amps: 1400.
- Nominal voltage: 12 volts.
Odyssey 31M-PC2150ST-M
Looking for a trusted power source? The Odyssey 31M-PC2150ST-M (on Amazon) is the perfect dual-purpose battery that provides great starting and deep cycle capabilities. This group 31 battery uses SpiralCell technology to provide users with reliable, clean energy as well as an amazingly high reserve capacity, so your power lasts even longer! Its robust design, efficient operation, and long reserves make it top of its class in quality – ideal for boats or RVs needing dependable electricity over extended periods.
Technical Features:
- Dimensions: 12.8 x 6.5 x 9.38 inches.
- Weight: 59.8 pounds.
- Capacity: 100 ampere-hours.
- Reserve capacity: 155 minutes.
- Cold cranking amps: 900.
- Cranking amps: 1100.
- Nominal voltage: 12 volts.
FAQs - Group 27 vs Group 31 Battery
What vehicles use group 31 batteries?
Fire trucks, ambulances – any heavy motorized vehicle really.
What vehicles use group 27 batteries?
SUVs of moderate size are usually running on them – mostly older types such as American cars like GMs and Hondas.
How long will a group 31 deep cycle battery last?
Usually, up to 5 years is stated as its lifespan!
Is a deep cycle battery the same as a marine battery?
Even though they share some similarities in design and purpose (deep cycle batteries are designed for extended discharge/recharge cycles, which makes them apt for marine applications), your typical “Marine” battery has been constructed specifically with harsh open water conditions in mind.
Can you use a marine battery in a car? Follow the link to learn more.
Which is better, group 24 or 27 battery?
Group 24 batteries are commonly utilized in smaller automobiles, whereas group 27 batteries are utilized in larger vehicles. Group 27 batteries will typically have a higher capacity and be more expensive than group 24 batteries.
How many amp-hours is a group 27 battery?
A typical group 27 battery will have between 66 and 110 amp hours.
What is the difference between Group 31 and 34 batteries?
The difference is the capacity, where Group 31 has 96 ah and Group 34 has 64 ah.
What is the difference between a Group 24 and a Group 27 battery?
Group 27 has a higher amp-hour capacity (70-85ah) than Group 24 (50-60ah).
Conclusion: Group 27 vs Group 31 Battery
In the end, it all comes down to your needs and requirements. Group 31 batteries may be more powerful than their smaller counterpart — Group 27 — but you still have to decide which will suit your purpose best before making a decision. Consider every factor carefully when making this important selection so that you can get exactly what works for you!
James is an engineer and a professional blogger. He has gained extensive experience over the years, handling all types of power projects. He loves to share his experiences with all things related to batteries, generators, and other power-related topics.
