I am considering Optima Batteries for replacement but was wondering about the onboard charger on my boat, will it be compatible. I know that they sell specific chargers and here are the charging specs:

* Alternator: 13.65 to 15.0 volts, no amperage limit.
* Battery charger: 13.8 to 15.0 volts, 10 amps maximum, 6-12 hours approximate.
* Cyclic Applications: 14.7 volts, no current limit as long as battery temperature remains below 125°F (51.7°C). When current falls below 1 amp, finish with 2 amp constant current for 1 hour for D34M and 3 amp constant current for 1 hour for D31M.
* Rapid Recharge: Maximum voltage 15.6 volts (regulated).
* Maximum current: No limit as long as temperature <125°F (51.7°C).
* Maximum recharge time: Charge until current drops below 1 amp.
* Float charge: 13.2 to 13.8 volts, 1 amp maximum current, time indefinite (at lower voltage).

My guess is not and I sure don't want to burn them up @ $250 ea.

Thats a good question I'm up for new batteries this year too. I run three batteries with a 160amp alternator for six subs and four six by nines with three thousand watt amps apiece. I've thought about them are they worth it? I've went three years on the biggest bats o'riley had for, I think it was less than $300for all three.

I just replaced mine with 2 top of the line Interstate batteries. The Optimas I had in my old boat lasted maybe a year or 2 at the most. I was dissapointed in their performance. The batteries that I replaced lasted almost 4 years. I run 4 subs and 6-6x9 speaker with 2- 1000w amps.

Good to know...

I have 2 Optima blue tops and an onboard charger. Never a problem. 4 10'subs 4 8"subs and 4 amps all kickin.

Is it the stock shore power charger or an aftermarket?

I have four in my boat, they been in there since 03 and i've never had a problem. they run 3 sub's, bunch of smaller speakers and a tv all day, i've never had a dead battery.. even in the spring after sitting all winter i've never even charged them..

im not sure about the shore power part.

The ones I had problems with were yellow tops. I don't know what the difference is, but my buddy had the same problem with those Optima batteries in his boat.

Chargers are specific for leaded, AGM (optimas) or Gel.


The chargers I seen require you to set the charger to the type of battery by DIP switches if the charger is compatible with the non leaded batteries. And no mixing and matching battery types. Don't know if they will do any harm if you use the wrong settings, other than leaded batteries use a higher charge rate. So just maybe you won't get a full charge using the wrong charger. Do a search for your charger brands home page.

I just bought a set of Delco Voyagers for my boat. I have had them before and they had lasted five years in my previous boat. I bought the Delcos to replace the stock Exides that Reggie put in when it was built in 04. They run $139 ea retail and jobber cost is at $83.00. No hassle and no maintenance.