BlueMax Marine Group 31
BlueMax Marine Group 31is backordered and will ship as soon as it is back in stock.
BlueMax Marine Group 31
Exceptional dual-purpose power for starting and deep-cycling all on one battery.
- Dual-Purpose Performance: Deliver a massive 1200 Cold Cranking Amps (CCA) to effortlessly start your marine engines while reserving 160Ah of deep-cycle capacity for house electronics.
- Massive Weight Reduction: Weighing only 38 lbs, this lithium battery shaves substantial weight off your vessel compared to traditional lead-acid equivalents, instantly improving speed and fuel efficiency.
- Intelligent Safety: Built with an Advanced Battery Management System (BMS) equipped with active cell balancing, low-voltage disconnect, and a reliable low-temperature charging cutoff.
- Proven Longevity: Engineered to provide 5,000+ cycles at 80% Depth of Discharge, maximizing your return on investment over years of harsh marine use.
What This Upgrade Fixes
Eliminate the anxiety of a dead starter battery after running trolling motors and electronics all day long. This upgrade ends the routine maintenance, heavy lifting, and frequent replacements associated with traditional lead-acid marine batteries. It also solves the problem of underperforming electronics caused by voltage sag—our LiFePO4 chemistry holds a steady voltage until completely depleted.
What's Included
[FILL: WHAT'S INCLUDED]
Compatibility
This is a universal flat-fit design manufactured in the standard Group 31 form factor, meaning it works as a direct drop-in replacement for existing Group 31 marine or RV battery setups. It operates seamlessly with standard 12V alternators and marine charging systems supporting a 14.2V - 14.6V charging profile. Ideal for marine house power, engine cranking, RV house banks, trolling motors, and solar storage applications.
Installation
Estimated Time: 15–30 minutes
Difficulty: Beginner
Tools Needed: Basic socket set or wrench to disconnect the old battery and torque your existing ring terminals onto the new battery posts.
Key Specs
| Nominal Voltage | 12.8V (12V System) |
| Capacity / Energy | 160Ah / 1980Wh |
| Cold Cranking Amps | 1200 CCA |
| Max Continuous Discharge | 160A |
| Charging Voltage | 14.2V - 14.6V |
| Chemistry | Lithium Iron Phosphate (LiFePO4) |
| Cycle Life | 5,000+ cycles at 80% DoD |
| Form Factor | Group 31 |
| Weight | 38 lbs |
| Operating Temperature | Discharging: -20°C to 60°C | Charging: 0°C to 45°C |
| Durability & Safety | IP67 Rated, Built-in Advanced BMS |
| Certifications | UL 1642, UL 1973, CE, RoHS, UN38.3 |
| Warranty | 8-Year Warranty |
FAQ
Can I use this battery to start my engine and run my trolling motor?
Yes. Unlike standard deep-cycle lithium batteries, this unit pushes 1200 CCA designed specifically for engine cranking, alongside providing 160Ah of true deep-cycle energy storage for motors and electronics.
Will this fit in my existing battery tray?
Yes, this is built precisely to a Group 31 blueprint. As long as your current setup accommodates a standard Group 31 battery, it is a simple drop-in swap.
Will the battery be damaged if I charge it in freezing weather?
No. The integrated BMS includes a low-temperature charging cutoff. If the internal temperature drops below 0°C (32°F), it automatically prevents a charge to protect the lithium cells from permanent damage.
Quick answer: the BlueMax Marine Group 31 from Fleet Lithium has nominal voltage 12.8V, capacity 160 AH, cycle life 5,000+ cycles at 80% Depth of Discharge (DoD), cell chemistry Lithium iron phosphate (LiFePO4), warranty 8 Year Warranty. The complete specification table for this configuration is below.
Electrical & Performance
- Nominal Voltage
- Capacity
- Nominal Energy
- Cold Crank Amps
- Charging Voltage
- Discharge Cutoff Voltage
- Cycle Life
Battery & BMS
- Cell Chemistry
- Battery Type
- BMS Features
- Advanced Battery Management System (BMS) , Active Cell Balancing for Extended Life Cycle
- Safety Features
- Low Temp Charging Cutoff , Over Charge / Discharge Protection , Over Current Protection , Low Voltage Disconnect (LVD)
- Battery Features
- Operating Temperature
- Charging: 0°C to 45°C (32°F to 113°F) , Discharging: -20°C to 60°C (-4°F to 140°F)
Dimensions & Weight
- Dimensions (L x W x H)
- Length
- Width
- Height
- Weight
- 38.0 lb
Warranty & Compliance
- Warranty
- Certifications & Standards
- UL 1642, UL 1973, CE, RoHS, UN 38.3, IP67
- Condition
Product Details
- Classification
- Colour / Finish
- Vendor
- Fleet Lithium
- Product Type
- 12 Volt Lithium
- SKU
- BM12V160
Pair it right
Make sure this pack matches your motor
Trolling motors pull about one amp per pound of thrust. Enter your motor, hours and throttle to confirm this capacity covers your day on the water.
Size your marine pack
—
Estimate based on ~1A per lb of thrust at 12V and 80% usable depth of discharge. Message us with your rig for an exact recommendation.
Match your system
Choose the battery voltage, dimensions and discharge rating required by your equipment.
Plan your capacity
Compare the listed amp-hour capacity with your equipment load and intended runtime. Actual runtime varies with use.
Check charging compatibility
Confirm that your charger and onboard charging system support the selected LiFePO4 battery.
10-year battery warranty
See Fleet Lithium warranty details for coverage and terms. Contact our team for help choosing the right battery.
Other Fleet Lithium marine batteries
BlueMax Marine 12V 195Ah LiFePO4 Deep Cycle Battery (Group 27)
BlueMax Marine 12V 105Ah LiFePO4 Battery (Group 24)
36V 150AH Trolling Motor Battery
- 10-year battery warranty
- Fleet Lithium support
- Match voltage and capacity
- Check charging compatibility
Let customers speak for us
What a fantastic upgrade from my old acid batteries. It was time and I’m so impressed. Shipping came smoothly. Customer service has been fantastic and looking forward to the adventures to come including camping, RV, fishing, boating.
The customer service and the battery itself from Fleet Lithium is unbeatable. One of the best experiences as a customer I have ever had. They stand by their product and help you every step of the way to ensure you are happy in your purchase. The install was easy once you know where everything is supposed to go and the battery has performed flawlessly in my Bad Boy Recoil since installation. It made it a lot lighter and the buggy is obviously quicker now and I was able to ride it around the farm for hours in fast mode the other day and only used 25% of the battery carrying a buddy and myself. It is really amazing.
Cannot thank these guys enough. Our Hunting buggy is a whole new animal of its own! The team did a great job answering questions, shipping took 3 days and i was even able to reach the support team at 4pm on a Saturday during install. Cannot thank them enough! Don't think twice, Fleet is the way to go for your lithium job.
Was a slight hick up with the darn computer bot. Once we got thru that the service and help with my change over was top notch.
Mt Ranger performance is awesome with the Fleet battery
GREAT SERVICE
Awesome kit. We Live in a very cold climate, our ranger gets a ton of use year round and especially during the winter so the cold weather performance was a must for us. We've had the kit installed for about a year now and it's been perfect. Customer service has been super helpful the one or two times we had questions and we've got a couple of neighbors who run the kits as well and they say the same thing. Kevin and his crew are really top notch!
The 12V voltage reducer corrected the unstable behavior that had affected the lights and other accessories. The output has remained steady through regular use.
The 51V replacement charger is easy to keep available as a backup and works without unnecessary controls. The battery reaches a complete charge consistently during normal use.
The Polaris Ranger EV bundle lined up well with the intended mounting area and the connections were easy to identify. Once installed, the vehicle felt smoother and more consistent through normal use.
The 51V replacement charger connected as expected and has charged the compatible battery consistently. The status indicators are easy to follow, and the unit feels solid in regular use.
Easy installation and great technical support.
After installing the Club Car 48V kit, throttle response felt more immediate and the vehicle no longer felt sluggish late in the charge. The cleaner battery compartment is another welcome improvement.
Cabels look great. Will be installing them by the end of the week. Frank
The BlueMax 200Ah marine battery has provided steady power for onboard electronics and normal time on the water. It is easier to handle than the older battery and has required very little attention between trips.
The parts for the EZGO TXT kit were organized clearly and the installation sequence made sense. The finished setup looks tidy and removes the routine upkeep of the old battery bank.
