Best 6V house batteries

[guitarguy]

Looking for advice on replacing 6V house batteries. Coach came with 6 Lifeline 300AH AGM's. I don't boondock so converting to Li may not be worth the cost but am open to opinions on that. Wondering if there are any better value AGM's out there I should consider. TIA for input....

[shootist]

If that’s all the life you got out of the agms I would just go with lead acid. Trojan builds the big ones like you have. You normally get ten years out of agms.

[l1v3fr33ord1]

guitarguy-

Please define "best" and "better value."

In my opinion, you already own the best-built AGM batteries, so I would recommend exact replacements.

It seems odd that you're looking to replace four-year-old batteries. I sold my coach with six-year-old Lifelines, and expected them to last at least another two years before needing replacement.

[shootist]

Originally Posted by l1v3fr33ord1

guitarguy-

Please define "best" and "better value."

In my opinion, you already own the best-built AGM batteries, so I would recommend exact replacements.

4 years old? They are not a good battery let alone the best. I install big d2’s in solar systems and always see 9 or ten years, no exceptions. Trojan builds agm too but wow are they expensive Trojan Motive J305-AGM 6V 310Ah Deep Cycle Sealed AGM Battery Made in USA

[l1v3fr33ord1]

Originally Posted by shootist

Trojan builds agm too but wow are they expensive

Yes, and Lifelines are expensive, too. The 300Ah GPL-6CT, at the site from which I've bought Lifelines, currently sells for $545 each, not including shipping (and shipping won't be cheap, at 90 pounds each).

[guitarguy]

Originally Posted by l1v3fr33ord1

guitarguy-

Please define "best" and "better value."

In my opinion, you already own the best-built AGM batteries, so I would recommend exact replacements.

It seems odd that you're looking to replace four-year-old batteries. I sold my coach with six-year-old Lifelines, and expected them to last at least another two years before needing replacement.

Thanks Mark, I don't know that they are bad yet. I inadvertantly let them drain to near zero (forgot to plug-in) and now they are taking a loooooong time to charge using my external charger. I'm just trying to plan for the possibility they may be fried.

[guitarguy]

Originally Posted by l1v3fr33ord1

Yes, and Lifelines are expensive, too. The 300Ah GPL-6CT, at the site from which I've bought Lifelines, currently sells for $545 each, not including shipping (and shipping won't be cheap, at 90 pounds each).

Not sure if these guys are legit but they're showing $485.00, ground shipping to Texas included. https://invertersrus.com/product/lifeline-gpl6ct/

[Winemaker2]

I've had very good service from AGM made by East Penn... a large and respected batty mfg. If you don't boondock much I'd consider Duracell 6V GC2 from Sam's Club.
I replaced my 8 FLA GCs w AGMs several yrs ago after refurbishing the batty tray & compartment.
I have 3 East Penn AGM 8Ds in our boat that are going on season #9 now and still doing well. They get stored for winter with no access to power and still holding up well. Lifeline are very well respected but close to 2X the $... I doubt they would run 15-18 yrs to break even or come out ahead$.
Lifelines may be recoverable as I believe they will accept a balancing charge that helps restore some lost capacity from mistreatment.

Sent from my SM-T878U using iRV2 - RV Forum mobile app

[Mnoel]

Originally Posted by guitarguy

Not sure if these guys are legit but they're showing $485.00, ground shipping to Texas included. https://invertersrus.com/product/lifeline-gpl6ct/

I purchased mine from them 2 year ago. Excellent service on the phone and shipped to my door in great condition. I always recommend them.

[jaydee325]

Originally Posted by guitarguy

Thanks Mark, I don't know that they are bad yet. I inadvertantly let them drain to near zero (forgot to plug-in) and now they are taking a loooooong time to charge using my external charger. I'm just trying to plan for the possibility they may be fried.

You have a 900AH battery bank. A standard external battery charger will take a LONG time!

What is the battery charger max output? You really need to be using a charger that has a bulk charge or equalize charge function.

[153stars]

Agree I'm adding up 1800 ah but 900 usable. Most bigger car chargers will do 30 amps max constant or boost per cycle rate. It will take a week at 30 amps. Once the inverter charger sees some voltage from charger it should kick in with my guess about 100amps from it. Try boost on charger see if inverter charger kicks in. I think lifelines accept a equalize charge check info . I would run equalize charge if so . You didn't do them any favors but not necessarily a goner... how long did they sit dead.

[twinboat]

Originally Posted by 153stars

Agree I'm adding up 1800 ah but 900 usable. Most bigger car chargers will do 30 amps max constant or boost per cycle rate. It will take a week at 30 amps. Once the inverter charger sees some voltage from charger it should kick in with my guess about 100amps from it. Try boost on charger see if inverter charger kicks in. I think lifelines accept a equalize charge check info . I would run equalize charge if so . You didn't do them any favors but not necessarily a goner... how long did they sit dead.

Cut your #s in half, they are 6 volt batteries.

[MN_Traveler]

With agms it is not so much about quality of the battery, but how you use them. Regular deep cycling (below 50%) and not recharging fully to float *every* cycle will drastically shorten life. Lifelines however can “come back” better than most if correctly treated … i recommend calling their tech support line and discuss. They might well be able to help you get these batteries back to reasonable working condition.

Lacking that, i would recommend charging to float, discharge slowly to 12 volts, repeat 2-3 times. *then* charge to float, run an eight hour equalization charge, then discharge slowly to 12 volts. Repeat *that* three times or so.

And yes, lifeline batteries *are* designed to accept an equalization charge…

[l1v3fr33ord1]

The Lifeline Battery Technical Manual (link here), page 22, has a section titled: "Deep Discharge Recovery."