Marine Batteries

Marine Batteries: Choosing a Lithium Deep Cycle Battery for Your Boat

Marine batteries in this collection are LiFePO4 deep cycle units built to run trolling motors, fish finders, cabin lights, a fridge and an inverter on a boat, then charge back up from the alternator, shore power or a solar panel. They replace the factory lead-acid house bank and are rated for 4,000 or more charge cycles, which is several times what you get from agm marine batteries of the same size.

There are 5 products here from Sungold Power, Rich Solar and BigBattery: 12V and 24V house batteries from 100Ah to 200Ah, a two-battery bundle, and a 72V pack for electric drive systems. Prices start at $589 for a 200Ah Sungold Power battery and top out at $2,450 for the 7.68kWh BigBattery RAPTOR 2.

How to choose a lithium marine battery

• Voltage matches the boat. Most runabouts and pontoons run a 12V house system; 24V trolling motors and larger cruisers use 24V. The Sungold Power 12V 200Ah LiFePO4 Deep Cycle Battery and the Sungold Power 24V 100Ah LiFePO4 Deep Cycle Battery store the same 2,560Wh, so pick by voltage, not capacity.
• Amp-hours per day on the water. A trolling motor on a long day, a livewell pump and electronics can drain 100Ah from a 12V bank. The Rich Solar 12V 200Ah ALPHA 2 LITE gives 2,560Wh with individually fused cells and a 4,000+ cycle rating for $730.
• Water protection. The Sungold Power units carry an IP65 rating, and the RAPTOR 2 is IP65 and NEMA 4X, so splash and spray in an open bilge are not a problem.
• Cold-water season. Lithium cells should not be charged below freezing. The Sungold Power batteries include self-heating, so an early spring launch or a late fall trip does not stall the charger.
• One battery or a pair. The 2 x Sungold Power 12V 100Ah LiFePO4 Batteries bundle lets you split weight between two compartments.

Popular picks in this collection

Setup and usage tips

• Check your charger before you swap. Older marine chargers have lead-acid or gel profiles only; a lithium battery needs a charger or a profile that stops at the correct voltage, or it will never reach full capacity.
• Use the Bluetooth app on the Sungold Power units to watch state of charge on the water instead of guessing from a voltmeter.
• Strap the battery down. Lithium is lighter than the lead-acid unit it replaces and moves more in chop unless the tray hardware is adjusted.
• Keep the starting battery separate. These are deep cycle house batteries; leave the engine start on its own battery and isolator.
• Planning to add a solar panel to the T-top or bimini? The Solar Kit Calculator estimates how much panel and battery you need from your electronics list and ZIP code.
• Buying lithium batteries for marine use in the north? Choose the self-heating models so shoreline charging keeps working through cold snaps.

Frequently asked questions

Can I replace marine gel batteries with these one for one? Usually yes, as long as the voltage matches and your charger has a lithium setting. A 12V 200Ah lithium battery delivers more usable capacity than a gel battery of the same label because it can be discharged deeper without damage.

Will a 100Ah lithium battery run a trolling motor all day? It depends on the motor's draw and how hard you run it. For full-day fishing on a 12V motor, the 200Ah Rich Solar or Sungold Power battery, or the two-battery bundle, is the safer choice.

Are these safe in an enclosed compartment? LiFePO4 chemistry does not off-gas during charging the way flooded batteries do, and the IP65 housings shrug off spray. Still keep the compartment ventilated and the terminals covered.

Every battery here ships free to the mainland US from our brand partner warehouses, usually within a few business days, and comes with 30-day returns. Call us with your boat's wiring details and we will confirm the right voltage and capacity before you order.