The Dakota Lithium DL+ 12V 640Ah is a very large LiFePO4 battery made for boats, RVs, solar systems, and off-grid power. It also has enough starting output for many large engines.
This is not a small camping battery. It weighs 121 pounds and stores far more energy than most portable power packs. It makes the most sense in a fixed system where high capacity and fewer batteries are worth the size and cost.
Key DL+ 640Ah Specs
- Capacity: 640Ah
- Nominal voltage: 12.8V
- Rated energy: 7,680Wh
- Starting power: 1,000 CCA
- Weight: 121 pounds
- Communication: CAN bus and NMEA
- Cold-weather feature: internal heating while charging
- Manufacturer warranty: 11 years
Dakota Lithium lists the battery for RVs, large boats, off-grid systems, and solar power. The maker also rates it for up to 5,000 cycles under recommended conditions.
A Correction on Energy Capacity
The older version of this review estimated 8,192Wh by multiplying 12.8V by 640Ah. Dakota Lithium currently lists the battery’s rated energy as 7,680Wh, so that is the figure we use here.
That is still a large amount of stored energy. Real run time depends on the load, inverter losses, temperature, wiring, battery settings, and how much capacity you choose to use.
It Is Built for Starting and Deep-Cycle Use
The DL+ line is dual purpose. The 640Ah model combines a large house-bank capacity with a 1,000 CCA starting rating.
That can reduce the number of batteries in some boats or RVs. It does not mean it is right for every engine or electrical system. Check the engine maker’s battery requirements and the Dakota Lithium manual before using one battery for both jobs.
Internal Heating Helps in Cold Weather
Cold charging is a concern with lithium batteries. This model has internal heating designed to warm the battery while charging in cold conditions.
That can be useful in winter RVs, boats, cabins, and other cold locations. The charging system still needs to match the battery maker’s requirements.
CAN Bus and NMEA Add System Data
CAN bus and NMEA communication can help a compatible system share battery data with displays and other equipment.
This feature is most useful in a planned marine, RV, or off-grid electrical system. Confirm compatibility before buying cables, displays, or controllers.
It Can Replace a Large Lead-Acid Bank
Dakota Lithium says one DL+ 640Ah can replace a bank of up to 12 AGM or flooded lead-acid batteries in some systems. That is a maker claim, not a rule for every installation.
Compare usable energy, voltage, peak current, charging needs, physical space, and required redundancy before removing an existing bank.
Good Fit for Large Boats
A large marine battery can run electronics, pumps, lights, refrigeration, and other house loads. This model can also provide starting power when the engine and installation are compatible.
For time on the water, our guide to finding fishing spots covers maps, structure, wind, water, and a simple scouting plan.
Good Fit for RV and Off-Grid Power
In an RV or cabin, 7,680Wh can support lights, a refrigerator, fans, electronics, pumps, and an inverter. The actual run time depends on your daily energy use.
If your trips are more about simple camps than large electrical systems, our boondocking guide explains water, power, waste, legal camping, and off-grid planning.
Plan Loads in Watt-Hours
Start by listing each device, its power draw, and how many hours it runs each day. Add those watt-hours together.
Do not divide 7,680Wh by an appliance rating and treat the result as a promise. Inverters, wiring, temperature, cycling limits, and changing loads all affect real use.
Charging Equipment Must Match
Do not copy generic lithium charging numbers from another battery. Use the voltage, current, temperature, and charger settings in the current Dakota Lithium instructions for this model.
The same rule applies to alternator charging, solar controllers, shore chargers, and inverter-chargers. A large lithium bank can place heavy demands on charging equipment.
Marine Installations Need Careful Design
Large lithium batteries can deliver very high current. Cable size, overcurrent protection, disconnects, mounting, charger settings, and the rest of the system must be designed for the expected load.
The U.S. Coast Guard boating safety guidance has pointed builders toward the ABYC E-13 lithium-battery standard for recreational boat installations. A qualified marine electrician is a smart choice for a system this large.
Secure 121 Pounds of Battery
At 121 pounds, this battery needs a strong mounting location. Boats and moving vehicles add vibration, turns, bumps, and sudden stops.
Follow the maker’s mounting instructions and make sure the structure can safely support the battery and its restraints.
Simple Camping Needs Less Power
A 640Ah fixed battery is far more than most tent campers need. A headlamp, phone, small fan, or weekend light setup can run from much smaller power sources.
Our camping packing checklist can help you decide what gear you actually need before building a large power system.
Useful Electrical Tools
A digital multimeter is useful for basic voltage checks and troubleshooting. It does not replace proper battery monitoring or safe electrical test procedures.
If you need one for a general tool kit, you can compare Klein Tools digital multimeters on Amazon.
Keep Cables Organized and Protected
Clean cable routing makes inspection easier and helps prevent abrasion. Use parts rated for the environment and the electrical load.
Heat-shrink tubing is useful for many low-voltage wiring jobs when it is the correct type and size. You can compare marine adhesive heat-shrink tubing on Amazon.
Think About the Whole Outdoor System
Battery capacity is only one part of a trip. Water, weather, food, fuel, communication, and backup plans matter too.
For another look at practical outdoor equipment, this guide to solar power for RV use can help frame the way panels, storage, and daily loads work together.
Who Should Consider the DL+ 640Ah?
- Large boats with heavy house loads
- RVs with large inverters or long off-grid stays
- Solar and cabin systems that need a large 12V bank
- Users who value CAN bus or NMEA integration
- Cold-weather systems that can benefit from internal heating
Who Probably Does Not Need It?
- Basic tent campers
- Small kayaks and simple electronics setups
- Users who need a lightweight portable battery
- Systems whose chargers or wiring cannot support a large lithium bank
The Bottom Line
The Dakota Lithium DL+ 12V 640Ah is a high-capacity battery for serious fixed power systems. Its main strengths are 640Ah of capacity, a 7,680Wh rating, 1,000 CCA, internal heating, and CAN bus and NMEA support.
The size of the battery also raises the stakes for installation. Verify the current manufacturer specifications, use compatible charging equipment, protect the wiring correctly, and get qualified help when the system is beyond your electrical experience.