Complete Guide to Group 31 Batteries
Everything you need to know about dimensions, specs, costs, and the best options for your vehicle in Orlando
A Group 31 battery is one of the most versatile heavy-duty battery sizes on the market—popular in trucks, buses, RVs, boats, and commercial fleets. If you need higher cold-cranking amps (CCA), longer reserve capacity, and dependable power for accessories, Group 31 often delivers the best mix of performance and value for Orlando drivers.
What Is a Group 31 Battery?
BCI (Battery Council International) standardizes battery "group sizes" so dimensions and fit are predictable. A typical Group 31 battery measures about 13.0″ × 6.8″ × 9.4″ (L×W×H). Exact terminal layout, chemistry (AGM, GEL, flooded), and performance ratings vary by model, so fitment and specs should be confirmed before purchase. If you're unsure, our team at Batteries Inc Orlando can test, size, and install the correct battery for your vehicle or vessel.
Group 31 Battery Dimensions & Standards
Shoppers searching for Group 31 battery dimensions are usually verifying physical fit and terminal orientation. BCI sizing keeps case footprints consistent, while the following can differ by brand: terminal type and position, CCA, reserve capacity (RC), and internal construction. Refer to the Battery Council International group size guide for size coding details, and feel free to ask our techs to confirm clearance and cable reach in your specific application.
Common Group 31 Applications in Orlando
Heavy-Duty Trucks & Fleets
Group 31 provides robust starting power and accessory support for trucks and commercial vehicles. See our Automotive Batteries and ask about fleet support.
Marine Applications
Fishing boats and larger vessels benefit from Group 31's higher RC and deep-cycle options for trolling motors and electronics. Explore our Marine Batteries.
RVs & Off-Grid Power
RV house banks often use Group 31 deep-cycle batteries for sustained loads. Browse RV Batteries.
Industrial & Specialty
Some industrial equipment and standby power systems spec Group 31 for durability and consistent output.
Types of Group 31 Batteries: AGM, GEL & Flooded
- AGM (Absorbed Glass Mat): Sealed, maintenance-free, spill-resistant, strong CCA, great vibration resistance—popular for fleets, trucks, and marine starting.
- GEL: Excellent deep-cycle performance and vibration resistance—well-suited for RV house loads and marine accessories. Requires correct charging profile.
- Flooded lead-acid: Traditional, budget-friendly option. Delivers dependable performance but requires periodic maintenance (fluid checks, venting).
Not sure which chemistry fits your use? Compare options on our AGM & GEL Batteries page or stop by for testing and a recommendation.
Key Specs That Matter (What to Look For)
Cold-Cranking Amps (CCA)
Indicates starting power in cold conditions. Many Group 31 models range from ~800 to 1000 CCA.
Reserve Capacity (RC)
Minutes the battery can deliver a specified load—crucial for accessories and emergencies. Group 31 often provides a higher RC than smaller groups.
Deep-Cycle vs. Starting
Choose deep-cycle for sustained loads (RVs, marine house banks) and starting for engines that need high burst current.
Maintenance Profile
AGM/GEL are sealed and maintenance-free; flooded batteries require occasional checks.
More questions? Our Battery FAQ covers fitment, charging, and care basics.
Group 31 vs. Other Common Battery Sizes (Quick Comparison)
| BCI Group | Typical Use | Approx. Size (L×W×H) | Reserve Capacity | Notes |
|---|---|---|---|---|
| Group 24 | Passenger cars, light marine | 10.2″ × 6.8″ × 8.9″ | Lower | Common OEM size; smaller footprint |
| Group 27 | Cars/light trucks, marine house | 12.1″ × 6.8″ × 8.9″ | Medium | Step-up in capacity vs Group 24 |
| Group 31 | Heavy-duty trucks, RV, marine, fleet | 13.0″ × 6.8″ × 9.4″ | Higher | Best for higher CCA/RC and accessories |
| Group 35 | Compact/midsize cars | 9.1″ × 6.9″ × 8.9″ | Lower | Fits smaller engine bays |
In short: if you're comparing Group 31 vs Group 27 (or Group 24), Group 31 delivers more reserve capacity and typically higher CCA—ideal for larger vehicles, marine, and RV applications.
Group 31 Battery Cost in Orlando
Pricing depends on chemistry, brand, and warranty. Here's a helpful range for shoppers comparing Group 31 battery cost locally:
| Type | Typical Price | Pros | Considerations |
|---|---|---|---|
| Flooded lead-acid | $180–$250 | Lowest upfront cost; widely available | Requires maintenance; less vibration resistant |
| AGM | $230–$350 | Maintenance-free; higher CCA; robust; spill-resistant | Higher initial price vs flooded |
| GEL (deep-cycle) | $240–$360 | Excellent deep-cycle performance | Lower peak CCA vs AGM; must use correct charger profile |
Tip: If you routinely run electronics (trolling motors, inverters, fridges), a deep-cycle AGM or GEL can be the best Group 31 battery for overall lifespan and performance.
Lifespan & Warranty Expectations
| Type | Typical Lifespan* | Typical Warranty | Best For |
|---|---|---|---|
| Flooded | ~3–4 years | 12–24 months | Budget replacements, light duty |
| AGM | ~4–5+ years | 24–36 months | Fleets, trucks, high vibration, strong starting |
| GEL | ~4–6 years | 24–36 months | Deep-cycle marine/RV, sustained accessory loads |
*Real-world life depends on heat, vibration, and charging. Orlando heat increases demand on batteries—use an appropriate charger and schedule yearly load tests.
Charging & Maintenance Tips (Orlando Climate)
- Use the right charger profile for AGM, GEL, or flooded models to avoid under/over-charging. See our chargers & tenders.
- Short trips and parasitic draws cause partial state-of-charge—periodically top up with a smart tender to preserve Group 31 battery lifespan.
- Keep terminals clean, tight, and protected from corrosion. Check grounds on trucks and boats.
- For deep-cycle banks, size charger amperage to ~10% of total Ah capacity to reduce recharge time and sulfation.
Need Help Choosing the Right Group 31 Battery?
Our experts will test your system and recommend the perfect battery for your needs
Get Expert Advice TodayTop Group 31 Options We Stock
We carry standard Group 31 starting batteries for trucks and fleets, AGM Group 31 for high vibration and strong CCA, and GEL deep-cycle Group 31 for marine and RV house loads. For size standards and cross-references, consult the BCI group size guide, then visit us for testing and installation.
Why Orlando Drivers Trust Batteries Inc
Unlike big-box chains, we test your system, verify fitment, and install the correct battery the first time. Whether you're managing a commercial fleet, prepping for a fishing trip, or replacing an RV house bank, our specialists match chemistry, CCA, and RC to your real-world use. Need accessories? We stock chargers and tenders to keep your new battery healthy year-round.
Group 31 Battery FAQs
What are Group 31 battery dimensions?
About 13.0″ × 6.8″ × 9.4″ (L×W×H). Terminal layout and chemistry vary—always confirm fit before purchase.
How long does a Group 31 battery last?
Most last ~3–5 years. AGM and GEL can last longer with proper charging and fewer high-heat cycles.
What's the difference between Group 27 and Group 31?
Group 31 is physically larger with higher reserve capacity and typically higher CCA—better for trucks, RVs, and marine.
How much does a Group 31 battery cost in Orlando?
Generally $180–$350 depending on chemistry and warranty. We provide testing and installation.
Is AGM better than flooded for Group 31?
For fleets and marine, AGM is often worth it for vibration resistance, maintenance-free design, and strong CCA.
To Sum It All Up
For heavy-duty starting and reliable accessory power, a Group 31 battery is a proven upgrade. Visit Batteries Inc Orlando for system testing, the right fit, and a professional install—then maintain peak performance with our smart chargers & tenders.
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