Lithium vs. led battery

[dkoons16]

1998 400 CMY, has (2) 454 7.4l mercury gas engines. Access is very difficult to the last (2) batteries. What are the PRO's & CON's of switching to Lithium batteries? Assuming it can even be done.

All (3) current batteries need/want to be replaced.

Thanks in advance,
D&D

[g36]

Suppose you mean lithium and flooded lead acid. Whats the "last 2 batteries" mean? Starting or house bank? How often are you checking them ? If its that hard to reach can you relocate those 2? I might would consider a agm or sealed lead acid before forking over the cost of the lithium. Either would require no water . The lithium technology would last longer but boy it would really be hard to spend that kind of money for lithium right now prices are better all the time but still.

[dkoons16]

Just bought the boat, trying to figure them out. All (3) were bone dry, refilled with distilled water - but one lost charge rather quickly after only 3-4 hours off shore power. Fell to 11.2, wouldn't start engine. had to switch over to other battery.
Thanks for your quick feedback, appreciated.

[SplashyLady]

If they were dry - they are now toast. Lithium-Ion batteries are impressive - and expensive! I put one on my genset and was amazed. 350 CCA and it weighs about 6 lbs. - and it will take 2000 charging cycles!

But a set of 100 AmpHr main batteries are going to set you back about $750 a pop on Amazon or whatever, compared to $250+ for AGM/hybrid, and $70 for a group 31 flooded lead battery at your local truck parts place. But the Li-ion battery weighs 1/3 what the lead batteries do - that makes a difference.

So it comes down to price vs. weight vs. convenience. A $100 Li-Ion made sense to me for my genny, but I could not get there to go Li-Ion on the mains. Maybe the price will come down n the future. But, as the EPA sticker always says "your mileage may be different."