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Lithium Marine Engine Starter Batteries

Lithium starter Battery with full protection BMS for ALL boats - from 1hp to big diesels ; Caterpiller, Yanmar, Volvo Penta, Cummings, MTU, MAN, Yamaha, Suzuki, Evinrude, Honda, John Deere, Mercury,
12V and 24V......These batteries also for use with bow thruster or windlass motors for high peak amps.

People speak of REpower to install newer more powerful and efficient engines; well, now is the time to REpower your battery with a lighter weight, more powerful lithium marine starter battery !, up to 1400A
Seaquest has batteries with and without bluetooth advanced warning notification.
Older engines out of warranty may not need that capability.


From 5hp to 1000hp Diesels , 12 or 24V, Seaquest can make a starter battery for your engine;
supercapacitor assistance for those operating in freezing temperatures down to - 40F.

diesel engine yacht

Prices are variable depending on clients battery needs, but, fora a standard engine starting battery, the prices are $200 and up.

Example - A $250 battery would weigh about 4 lbs and deliver 600 cranking amps at between 40 and 100 degrees outside.

No special charger needed as the engine will keep battery charged.

3 year mfgr defect warranty

SuperCap Graphene subzero starterboost.jpg

When comparing starter cranking lithium marine batteries: 1st off.. there is no such thing as CCA or cold cranking amps for a lithium battery. That rating is for PbA batteries only.  The only # that matters is MCA / Marine Cranking Amps.
All Seaquest lithium replacement starting  batteries have a full BMS with all the protections you expect plus you can
match the battery to the engine you have, this way you dont buy too much or too little battery.
Look at the other suppliers offerings: Some offer a "dual purpose" 100Ah or so battery, which is simply a relabeled
deep cycle battery.  How can you tell ?? , look at the continuous rating. Deep cycle are all ONE C rated. THATS why they are so cheap.... Of course, I can match them and make the wild claims as well and still beat their prices.

Seaquest uses LiFePO4 high rated cells for starting at a 10C to 30C continuous rating.
Power range is from 12Ah @ 400 MCA   to  60Ah  @ 1800 MCA and  they DO work with ALL marine engines, 12 or 24V.
Seaquest does NOT recommend using the starter battery for any other use other than starting. Do not share the starter battery power with anything else that would drain the battery. Doing so invites a drain and SOC depletion that will result in a weak start and higher voltage drop.

Get a separate starter battery and a separate house / electronics battery.
Be advised that typical gas engines do not need more than 400A to start. ( big diesels excepted) The reason engine mfrs ' advise ' 1000+ cca, ca, whatever, is to minimize the voltage drop upon starting for the elec. ignition system. The lead acid batteries they have tested and approved of DO have a large voltage drop upon starting so, thats why they recommend overly large capacity, cranking amps.... It's all based on the lead acid model.
Please contact us at
seaquestbattery@gmail for further info .   ALL batteries are made to order.
A word about using lithium starter battery with Mercury engines; referencing the service bulletin:
Mercury acknowledges the use of lithiums, doesnt forbid their use, and warns that damage from such a lithium starter battery will not be warrantied, doesnt approve of any particular brand and lets owners decide for themselves.
Any lithium starting battery must have a BMS capable of  NOT disconnecting upon any overvoltage spikes, or short overcharging episodes.  Seaquest starting batteries will work just fine starting your engine.
Seaquest cranking battery weight for smaller engines is 7 to 12Ah and 3 -5 lbs, bigger engines: 18 to 24Ah and  7-10 lbs.
( Seaquest starting batteries have not been tested by any engine mfgr at this time.
OPTIONAL: Auto-jump 2ndStart feature is an available option for no extra charge. This is a wireless activation feature that prevents your battery from ever draining completely down, leaving you with reserve power in an emergency.

Final word on warranties

Battery tray's / brackets to secure battery are available.
Please submit drawing / hole pattern for custom fabrication
Legally, a  manufacturer cannot void the warranty on their product due to an aftermarket part unless they can prove that the aftermarket part caused or contributed to the failure in said product (per the Magnuson Moss Warranty Act (15 U.S.C. 2302(C)).  If your engine manufacturer fails to honor warranty claims, contact EPA at (202) 260-2080  If federal warranty protection is denied, contact the FTC at (202) 326-3128

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