Let's talk marine batteries
 

What do you like and why?

( need to re-do everything this spring) I was thinking of two lifeline 8D's for the house load and 1 group 31 for the starting battery.

I have been leaning to AGM's because they are sealed and will work in any orientation. But I had an AGM go bad on my other boat for some reason after a deep discharge. (pump left on for a few days) and it would not hold the charge very long after. I replaced it with a new one and all was good again.

What do you like and why?

Jim, I have great results with the AGM, one of there biggest plus is the ability to go way down and bounce back. You must have had a lemon. Good luck with the new ride,,,looks really nice.

Those AGM's you had trouble with were not Optima's were they?

No, they were something I purchased from west marine. (Sea Volt brand I think). Over all they were fine for a couple of years but that one time I really discharged it to zero (by accident) the house battery was kaput after that. I bought it back and they tested it, and the machine just said "error" and it was a few weeks after the warranty expired (figures), they were group 27's. I replaced both of them (and sold them with the boat) and I still have the other old one and it is still very strong. One thing I learned that the output from most outboards alternators is not that great unless your running 5000rpm.

I am boning up on my marine electrical. I see a lot of things I want to change/add. I want to change the way the battery wiring /switches are laid out. I don't see the logic in the current layout. If I get in over my head I will bring it to an expert but I think I can straighten it out. I like doing it myself if I can this way I understand the inner workings if (when) something breaks.

A buddy told me once...in general buy batteries by weight: heavier= better. I like the theory behind AGM's I think they make the best sense for boats. However in the past there were two types of batteries: Deep Cycle and Starting. I understand they differences but the new AGMS are " Dual use", Both deep cycle and starting. There must be some advantage one way or the other I would think. Is a classic "starting battery" better than a "dual use" battery for starting and engine?

Isn't that the truth! found that out more than once working w/ the r/v.

We killed one of our group 24 AGM SeaVolts after a severe draw-down too Jim, so it does happen, whatever they do say.

Jim,
Check out the Marine AGM batteries from Sears,these are made by Odessey for Sears and have heard good thing about them and the odessey's,but only come the largest is a group 31 I believe.

DieHard Marine Battery, Platinum PM-1 - Group Size 31M (with exchange)

Mike

I've been running 4D size seavolts for three years now. No problems except that I did ruin one by running it to zero. They can't take being run down that far and bounce back. I have one for each engine and one for the electronics/emergency.

I have two interstate that seem to work ok. Did have a dead battery a couple of times. Wasn't the batterys fault. I had them tested at the ZONE and seemed fine. I will charge them up this winter and use them again

maybe a dumb question, but what's "AGM"?

I have 2 batteries that will now die if left sit for a couple of weeks. Since I like to go off shore, I'm dumping them next spring for a piece of mind.

Look at the Sears link "Wrench" put up,,, $250 Each? Holly S%$#

I knew they where gona cost me, but never would have guessed that.

Maybe guys on those boats with bed sheets stuck to a pole have it right.

Never mind, back to reality,, small price to pay to go anywhere the wind does not blow.

Absorbed Glass Mat

The Odyssey 34M-PC1500 is the top dog in AGM batteries.