Expected Lifespan of Lifeline AGM's

[CaptRory]

I've been cruising along on my house bank of 4 Lifeline 6 volt AGM batteries for 6 years. My starting battery failed while all the batteries were linked up (switch on "all") and killed my charger and ran down the house bank to zip. So...my charger is toast, my starter battery is toast. But... I left the house bank isolated on the solar panels for 5 days and came back to a topped off bank. They have behaved themselves like I expect them too...challenged by rainy days and coming back up in the sunshine. I'm just wondering how long I should expect them to continue to perform. The warrantee is 5 years and they have been cruising along for 6. I expect some of you have been cruising along on them for decades and others cooked them in two. What do ya'll think I should expect from mine?

[robert sailor]

It really depends how well they were looked after and the charging regime that you've followed. I got 8 years out of ours and they still had decent life left but we were doing a crossing and decided to buy new ones. I gave the batteries away and the fellow is still using them but he's a weekend sailor so the batteries are always floating.

[barnakiel]

I have seen claims (from manufacturers) of up to 8/10 (!) years' life. But I have never seen an 8 year warranty. This makes me think.

You may get lucky and live beyond that but imho 5 years is often the point when batteries start to fail at a much accelerated rate, no matter what technology.

b.

[StuM]

Ijmpossible to tell without knowing a lot more about your usage. Are you cruising full time or is the boat mainly docked with shorepower?

How low do they get overnight when cruising? How do you recharge them when cruising? How many Ah and how much solar do you have? etc, etc, etc.

[smac999]

the best test is to do a c20 discharge test. you'll want your charger fixed so you can fully charge them before and after the test.

then you'll know the exact state of them

[john61ct]

Only way to really tell is a standard 20-hour load test once FULLY charged or with special gear by a pro.


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Sorry to be that guy, but I'd like to extract some learning experience here. This scenario is one mentioned by opponents of combining, and the most common rebuttal is that such events are very rare, at least on setups properly installed and managed.

Did that starter battery fail so catastrophically with no prior warning at all?

Or do you keep your banks combined for extended periods as part of the normal routine?

What do you think you will you now be changing about your system's design?

[CaptRory]

Originally Posted by john61ct

Only way to really tell is a standard 20-hour load test once FULLY charged or with special gear by a pro.


----
Sorry to be that guy, but I'd like to extract some learning experience here. This scenario is one mentioned by opponents of combining, and the most common rebuttal is that such events are very rare, at least on setups properly installed and managed.

Did that starter battery fail so catastrophically with no prior warning at all?

Or do you keep your banks combined for extended periods as part of the normal routine?

What do you think you will you now be changing about your system's design?

Ok... It's a 440 AH bank being charged with a 40 amp, three stage smart charger at the dock and a pair of 185 watt solar panels. When I bought the boat, I installed the house bank and kept one of the old group 27's as a starting battery, so I have no idea how old it is. I've got the normal stuff... a refrigerator that draws maybe 4 amps, LED house lights and running lights, a plotter and and autopilot. I have to try pretty hard to run the house bank down...the solar array keeps 'em up. I have been in condo mode at the dock for a year, which is why they were on "ALL" with the charger on and I wasn't paying attention. What I will do different is start the engine with the starting battery and charge it with the engine and otherwise keep it isolated. I'm not going back to isolators or combiners, they always fail on me so I'm keeping it KISS. Even at the dock, I will let the solar panels keep the house bank up unless there is prolonged bad weather. If I'm going to leave the boat for more than a week, I will empty the frig and turn it off, assuring a topped off bank when I return. So now, I'm getting ready to head out into the keys and Bahamas... I don't want to throw away money, but I'm considering replacing what appear to be good batteries based on their age because replacing the starting battery and charger will have the whole system out on the deck...

[a64pilot]

6 years I'd risk it. 8 probably not.
I think I would equalize them though

[Eder]

Mine are almost 9 years old...still going strong.

[Terra Nova]

One client got 10 years out of 3 lifeline 8D's.

[john61ct]

Forgive the apparent levity, I do feel for you. . .

Originally Posted by CaptRory

When I bought the boat, I installed the house bank and kept one of the old group 27's as a starting battery, so I have no idea how old it is.

Strike 1. How much is a brand spanking new auto Starter from Costco?

Keep an eye on its health over time, maybe buy new after 4-5 years even seems fine?

Originally Posted by CaptRory

I have been in condo mode at the dock for a year, which is why they were on "ALL" with the charger on and I wasn't paying attention.

Big strike 2!

I would say make sure your wiring, switch, gadgets setup enable you to completely forget that ALL switch, even better toss it overboard.

Switching loads between banks **for usage** can be a 3-position switch off/1/2, no All.

Combining like ALL switch should ONLY be used when jump starting is necessary AND even then, only after you've checked the problem isn't a FUBAR dangerous bank on the bad side, just normal over-depleted.

Originally Posted by CaptRory

What I will do different is start the engine with the starting battery and charge it with the engine and otherwise keep it isolated.

Personally, I think combining banks for charging should be OK, but **only** if automatic, a little charge requirement like a starter, Xantrex Echo Charge is solid and extra protection of one-way flow only, limited to 15A.

Otherwise you have what 2 Alts? Or enough solar that house doesn't need the alt output? Or solar has two outputs, also keeps starter topped up?

Any of those is fine I guess, long as the ONLY time you are combining "for use", is rarely needed self-jump starting.

Never relying on memory to combine for charging.

Using a proven bulletproof low-amp automated isolator/combiner to let you take advantage of all your available charge sources seems to me a better way to go.

And yes, I'd start over with fresh known good banks, don't forget to break them in properly.

And consider closer (any?) state of health testing every once in a while, proper system includes routine maintenance checklists to prevent such surprises. . .

[Scrimshaw4]

Battery life is realistically measured in terms of charge cycles. Contrary to popular belief AGM's can be "shook". I've had my 6v banks of Lifelines for 7 years and equalize them annually for 8 hrs. with my house charging system and they're practically as strong as new. jmho

[sailorboy1]

[QUOTE=CaptRory;2318240 What do ya'll think I should expect from mine?[/QUOTE]

So how's the voltage in the morning? When my batteries starting being lower in the mornings than I was comfortable with it was the sign to me to replace them. It matters little how much of the original capacity the batteries have, all that matters is whether they meet your needs. I bet lots of boaters keep using their batteries for 1-2 years after they start indicating it is time to replace.

And of course the real answer of how long batteries will last depends on who is in charge, them or you.

[Suijin]

My Lifelines are four years old, live aboard and use them year round, no solar, and were doing great. Winter of 15/16 the boat was hauled and I left it for for four months, and some *$% disconnected the shore power cord and when I returned they were dead. Charged them up and I'd say they're at 75% of original capacity at this point. So I'd say you probably did some damage. You didn't say how long they sat discharged, which is part of the issue. No way to know unless you do a full test.

[john61ct]

Originally Posted by Suijin

My Lifelines are four years old, live aboard and use them year round, no solar, and were doing great. Winter of 15/16 the boat was hauled and I left it for for four months, and some *$% disconnected the shore power cord and when I returned they were dead.

Wow. What arrangements can be made to ensure the caretakers have to take responsibility for that? Like the parking attendant pulling a Ferris Bueller. . .

And are there monitoring/alarm systems that can send out texts?