AGM Battery

[lookoutnw]

I am looking at the following batteries:

They are the AGM that are approx 22"L X 5"W X 13"H
Terminal/lugs on the end

Odyssey PC18oo
North Star Energy 1 NSB 210
MasterVolt 200ah

Does anyone have exerience with them?
I am setting up for long term cruising and need good battery banks.
I have enough room for 5-6 of them
I have 2 ea 135W solar panels, 1 AIRX Windgen, 120ADC Balmar, 5KW Genset

I hate wasteing money....

[deckofficer]

I've had very good experience with Odyssey batteries. I have used them in electric vehicles and other projects. They have a dual personality of being both a rugged deep cycle battery and having more cranking amps per pound of battery weight of anything offered. Lowest self discharge also.

If weight and cycle life is an issue, have you considered LiFePO4 Batteries? They have come down in price to the point if you factor in cycle life, are now cheaper than a high end AGM like the Odyssey.
If you cycle down to 70% DOD, you get >5000 cycles before the battery can only hold 80% of charge, or in other words, many care free years of no battery replacements.

Thundersky Lithium Batteries

Very informative posts on this forum here
http://www.cruisersforum.com/forums/...nks-65069.html

And if you still decide to go with AGM Odyssey, you should pick a case that has the highest production numbers like a group 24, 27, 31, that will have the lowest cost per A/hr.

[Paul L]

I had a very poor experience with the Northstar AGM (premature failure on 2, lousy manufacturer support, great reseller support). Add the Victron AGMs to your list. Had good experience with them.

[hellosailor]

Bob-
"If you cycle down to 70% DOD, you get >5000 cycles before the battery can only hold 80% of charge"
In theory, sure. But if a battery was being really pushed and deep cycled every other day (alternating two banks) those 5000 cycles would take 10000 days, or 27 years. So let's deep cycle that lithium battery EVERY day, it should still last 13-1/2 years.
Well, if that's the claim, how about some battery maker putting their money where their mouth is and putting a TEN YEAR WARRANTY on the product? Nope, no one is doing that.
Why should we believe it when there's no one backing up the claim with their wallet?
Now, I've had AGM's last one year to eight years--same battery, different application and charging, neither perfect. Sure didn't have 80% power left at the end, they were bellyup at that point.
But if the Lithium guys want to be believed, either they'll have to wait ten years, maybe 20 years, for users to start reporting life cycles, or they'll have to play a better game. And stop fighting among themselves as to how expensive and exotic the charge systems do or don't need to be.
Apparently that's too much to ask?

[mbianka]

Originally Posted by hellosailor

Bob-
"If you cycle down to 70% DOD, you get >5000 cycles before the battery can only hold 80% of charge"
In theory, sure. But if a battery was being really pushed and deep cycled every other day (alternating two banks) those 5000 cycles would take 10000 days, or 27 years. So let's deep cycle that lithium battery EVERY day, it should still last 13-1/2 years.
Well, if that's the claim, how about some battery maker putting their money where their mouth is and putting a TEN YEAR WARRANTY on the product? Nope, no one is doing that.
Why should we believe it when there's no one backing up the claim with their wallet?
Now, I've had AGM's last one year to eight years--same battery, different application and charging, neither perfect. Sure didn't have 80% power left at the end, they were bellyup at that point.
But if the Lithium guys want to be believed, either they'll have to wait ten years, maybe 20 years, for users to start reporting life cycles, or they'll have to play a better game. And stop fighting among themselves as to how expensive and exotic the charge systems do or don't need to be.
Apparently that's too much to ask?

A good point. I converted to electric propulsion in 2008 and have 4 AGM 8A4D batteries in series to make 48 volts for the propulsion system. The batteries are all holding up very well. About to start the fifth year with them. When they do finally need to be replaced I'll look around and see what the state of battery technology is. If the the track record for lithium is proved by then and the price point is better I might switch. But, for now I think AGM is the best choice from a price, maintenance and availabilty standpoint.

[deckofficer]

I wonder except for engine starting batteries, if anyone would warrant the cycle life of a product that has to be properly cared for to reach a given life expectancy? Nothing harms the life of a battery more than being run flat and being left that way for days or weeks.

I take good care of batteries, still using the original iphone, started my hot rod with the same Odyssey PC680 for 17 years and now it is used in my garden tractor, and for my EVs, always a good life from the batteries. I have no doubt if the manufacturer claims 5000 cycles if properly cared for, I will attain that life.

[hellosailor]

Mike, that's what I had thought too. But while enjoying the literary brillaince of Deka/East Penn, I found their statements that GEL beats AGM hands down, flat out, for larger number of deep cycles and better at coming back from deep discharges.

The only apparently drawback being that gels want different charging curves, they cook off before AGMs or wet cells. That doesn't seem to be a problem these days, if you are using a "proper" system with a programmable charger to start with, as opposed to an automotive alternator/regulator. (Unless I'm missing something, like gels being physically much larger. Didn't run off to check, not buying any batteries tonight.<G>)

[mbianka]

Originally Posted by hellosailor

Mike, that's what I had thought too. But while enjoying the literary brillaince of Deka/East Penn, I found their statements that GEL beats AGM hands down, flat out, for larger number of deep cycles and better at coming back from deep discharges.

The only apparently drawback being that gels want different charging curves, they cook off before AGMs or wet cells. That doesn't seem to be a problem these days, if you are using a "proper" system with a programmable charger to start with, as opposed to an automotive alternator/regulator. (Unless I'm missing something, like gels being physically much larger. Didn't run off to check, not buying any batteries tonight.<G>)

Actually my house bank is two group 27 Gels. Only reason I bought them was because my Pro Mariner charger only had charging curves for either flooded or Gel baterries. I wonder if a lot of batteries fail for people because they don't pay attention to having the right charging curves on their battery chargers. Both my electric propulsion bank (AGM) and my house (Gel) bank are the same age and both seem to be doing fine after almost five years. But, as Deck officer mentioned it's best to charge em early and often after use. Which I do either with my Honda 2000 generator or my solar panels and wind generator. All charging sources are setup for the type of battery they are charging too.

[hellosailor]

Mike,
Every time I make the mistake of looking at chargers/controllers versus particular batteries...it seems like every battery maker has their own idea of "optimum" and "maximum" and unless you have a fully programmable charger, it never matches the batteries. (OK, plain auto store wet cells sometimes match.<G>)

I suppose as I get more educated in this stuff I'll find SOME vendors with matching specs, or SOME vendors who are just full of rose food, but I'm actually having evil thoughts about circuit design and some of the new terribly intelligent "charge control" ICs that exist today.

I'm just glad the battery guys haven't done like the mattress companies did: Oh, no, if it isn't six inches thicker than your sheets, you'll just never be able to sleep on it. Gee, no, we don't know how you can buy sheets that fit a proper new mattress."

You know? A "plain" mattress has grown from 6" thick to 12" and if you want a GOOD one, well, that's 14-16" thick. As a politically incorrect TV show about a clown used to say "HOMEY DON'T THINK SO!" (WHAP!)

Come, we go to former Soviet Union, buy surplus strontium-pile navigation beacon. Install under keel and water around boat glow pretty blue all night, too. Not to recharge necessary one hundred years. (Honest.)

[mbianka]

Originally Posted by hellosailor

Mike,
Every time I make the mistake of looking at chargers/controllers versus particular batteries...it seems like every battery maker has their own idea of "optimum" and "maximum" and unless you have a fully programmable charger, it never matches the batteries. (OK, plain auto store wet cells sometimes match.<G>)

I suppose as I get more educated in this stuff I'll find SOME vendors with matching specs, or SOME vendors who are just full of rose food, but I'm actually having evil thoughts about circuit design and some of the new terribly intelligent "charge control" ICs that exist today.

I'm just glad the battery guys haven't done like the mattress companies did: Oh, no, if it isn't six inches thicker than your sheets, you'll just never be able to sleep on it. Gee, no, we don't know how you can buy sheets that fit a proper new mattress."

You know? A "plain" mattress has grown from 6" thick to 12" and if you want a GOOD one, well, that's 14-16" thick. As a politically incorrect TV show about a clown used to say "HOMEY DON'T THINK SO!" (WHAP!)

Come, we go to former Soviet Union, buy surplus strontium-pile navigation beacon. Install under keel and water around boat glow pretty blue all night, too. Not to recharge necessary one hundred years. (Honest.)

Yeah, I know what you mean. I went through an expensive learning curve when I installed my electric propulsion system back in 2008. I bought a pretty sophisticated 48 volt charger for the EP battery bank. Programmed at the factory for my 210 amp AGM bank. Worked well and can even drive my boat at 3 knots for hours. Only thing as it finishes charging I would see the battery voltage spike up to 62 volts. Calls to the U.S. distributor were not real helpful if this was normal. I could send it back and pay their flat rate $130 repair fee to have them check it out if I wanted to though. Since the battery bank seemed happy I instead ordered another battery charger for $600. I hooked it up and same damn 62 volts appears near the end of the charge cycle. At least I have a spare battery charger now. The battery bank has been happy for five years so far and nothing seems broken so I'm not about to fix it.

[deckofficer]

At that voltage, an equalizing charge (and then some) is performed every time you perform a full charge.

[mbianka]

Originally Posted by deckofficer

At that voltage, an equalizing charge (and then some) is performed every time you perform a full charge.

Yeah, I found that out eventually. Just wish the distributor could have told me that when I asked about it. Though having a spare battery charger is not such a bad idea anyway.

[Kettlewell]

I found their statements that GEL beats AGM hands down, flat out, for larger number of deep cycles and better at coming back from deep discharges.

Based on nothing other than my own unscientific use of some of the first Sonnenschein batteries I would confirm this. I installed several of these on a catamaran that I then lived aboard continuously for around 12 years and at the end the original batteries were still going strong and they were totally abused. Since I had no engine power to speak of (an outboard) most of the charging came from a small wind generator and some solar panels with no regulation whatsoever. I just kept an eye on an analog volt meter and disconnected things when the voltage started to get too high. Many times I flattened the batteries so far that I couldn't start the motor, and yet they kept coming back for more. Maybe I was just tremendously lucky but I was impressed with gels after that.

[hellosailor]

"Just wish the distributor could have told me that when I asked about it."

Well, an informed customer is sometimes bad for business. In some minds.

OTOH it is slowly getting simpler to get equipment, or set equipment, so it actually matches specs and to confirm what is or isn't going on. Last time I looked into calibrating my meters, it would have meant sending them out. This year, I found precision 10v references, which is arguably good enough to calibrate meters for 12v uses. Now I just need some mini Altoids tins <G> so I can keep one in my tool bag.

The chipsets behind the programmable charge controllers have finally become mainstream, so everything isn't custom designed and some of the stuff is even closer to reasonably priced. Easy, not quite yet. Feasible, oh yeah.

[CarlF]

I have an Odyssey house bank. They are working great but it's only been three years. We'll know in a three more.

I believe that there is an emerging consensus that AGM batteries are not a good choice for cruisers who use the the traditional wet cell system of draining to 50% then charging to 80%. This appears to kill AGM's in less than a year. Gels tolerate it fine.

AGM's are great if fully re-charged. There is no better dedicated engine start battery. They also do just fine if a boat is plugged into a marina frequently.

AGM's may work for you too because you have solar and wind. This is is good for AGM's if you normally get them charged enough with the engine that the wind/solar can continue to float charge them for at least several hours after the batteries are at 100%. This may mean that you need to charge with the engine to 80% and let the solar/wind finish the job.

And a warning. Except in a social gathering of cruisers, nothing will clear out a room faster than launching into a discussion of battery chemistry.

Carl