New to the Forum - Battery Question

[Freed Spirit]

Hi Folks,
East Penn Deka batteries have been strongly recommended to me for my 40' monohull. I am wanting to get 3 new 4D AGM's. The person I spoke to is a very experienced sailor and has had them on his boat for, get this, 12 years! Has anyone else had experience with East Penn Deka's? Are they that good? Price is about half of Lifelines.
Thanks from a newbie!
Gary
Freed Spirit

[NewMoon]

My first house bank of Deka AGM's, 2x 12V group 31's, lasted 11 summers of cruising. No generator, lots of overnight anchoring with no charging system on, and charged mostly by the Balmar alternator and smart regulator. Sure worked well for me.

[Finistere]

Last house bank of 4 Deka group 31 lasted 12 years


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[ranger58sb]

Gary, if these are for your house loads, you might search the forum for info about the virtues of true deep cycle 6V golf cart batteries.


-Chris

[GordMay]

Greetings and welcome aboard the CF, Gary.

[Maine Sail]

Originally Posted by Freed Spirit

Hi Folks,
East Penn Deka batteries have been strongly recommended to me for my 40' monohull. I am wanting to get 3 new 4D AGM's. The person I spoke to is a very experienced sailor and has had them on his boat for, get this, 12 years! Has anyone else had experience with East Penn Deka's? Are they that good? Price is about half of Lifelines.
Thanks from a newbie!
Gary
Freed Spirit

Sounds like he had Deka GEL batteries not their AGM's..... This would not be out of the ordinary for a Deka GEL bank, but would be like winning the lottery for a Deka AGM, could happen but pretty unlikely.

The Deka AGM's are rated for considerably less deep cycles than the Deka GEL batteries, 370 cycles for Deka AGM and 1000 cycles for the Deka GEL...

You also may want to check out the May 2015 issue of Practical Sailor where PSOC (partial state of charge) use was examined in AGM batteries. Not all AGM batteries are built the same, and this article could pay for itself with one poor purchasing decision...

Fighting Sulfation In AGM's - Practical Sailor (LINK)




.

[btrayfors]

I'm betting MaineSail is right: never saw an AGM battery in service last 10-12 years. But, have seen lots of gels do that.

One problem with such reports is that there is no standard for "end of service". ALL LA batteries -- flooded, AGM, gels, etc. -- begin losing capacity shortly after they are manufactured. They continue to do so until the user judges them to be in need of replacement.

OK, when is that? When they have only 90% of original capacity remaining? Or 80%? Or 70%? Or 50%? Or even less??

We tend to use car batteries until they won't start the car any longer. At this point, they may have only a fraction of their original capacity remaining, but the day before when they started the car they were still "good".

Of the three main types of LA batteries, the gels have the longest usable life, flooded batteries next, and AGMs dead last.

For many sailors, and depending on how you use your boat, AGMs are a terrible choice.

Bill

[ranger58sb]

Originally Posted by Maine Sail

You also may want to check out the May 2015 issue of Practical Sailor where PSOC (partial state of charge) use was examined in AGM batteries. Not all AGM batteries are built the same, and this article could pay for itself with one poor purchasing decision...

Fighting Sulfation In AGM's - Practical Sailor (LINK)

Thanks for posting that!

Originally Posted by btrayfors

I'm betting MaineSail is right: never saw an AGM battery in service last 10-12 years. But, have seen lots of gels do that.

Our oldest AGM bank -- 3x Odyssey PC2150s (G31s) -- has just entered its tenth season, and seems to be hanging in there.

OTOH, I don't have a SOC meter... and also we typically recharge on shorepower often (usually daily) or sometimes 2x/day on the genset for a week or two here or there). IOW, our PSOC usage is limited, unlike what more typical cruisers here face

-Chris

[Maine Sail]

Originally Posted by ranger42c

Thanks for posting that!






Our oldest AGM bank -- 3x Odyssey PC2150s (G31s) -- has just entered its tenth season, and seems to be hanging in there.

OTOH, I don't have a SOC meter... and also we typically recharge on shorepower often (usually daily) or sometimes 2x/day on the genset for a week or two here or there). IOW, our PSOC usage is limited, unlike what more typical cruisers here face

-Chris

Not atypical life for what I call UPS / uninterrupted power supply use with a premium AGM battery. If you tie to a dock every day or get back to full regularly any battery can last a long time.. If however you start to deep cycle and do not get back to full regularly then your batteries can sulfate rather quickly. The Odyssey did quite well in the Practical Sailor PSOC testing and was only beat by the Firefly AGM...

I regularly capacity test AGM & GEL batteries from boats that are cruised or mooring sailed. The differences between the PSOC deep cycling AGM's and dock sailed AGM's is like night and day... Solar can dramatically lenghthen life for those who sail off moorings...

[solarsam]

You should get the east penn batteries they will treat you well

[ranger58sb]

Originally Posted by Maine Sail

Not atypical life for what I call UPS / uninterrupted power supply use with a premium AGM battery. If you tie to a dock every day or get back to full regularly any battery can last a long time.. If however you start to deep cycle and do not get back to full regularly then your batteries can sulfate rather quickly. The Odyssey did quite well in the Practical Sailor PSOC testing and was only beat by the Firefly AGM...

That's a very apt description of our situation. And I've been pleased with the Odysseys. Although I'm still mostly planning to replace that bank of 3x G31s with 4x Lifeline GC2s whenever the time comes.

Driven partly by hours of trolling on one engine; at least half that time, it means our electronics suite (on the bank in question) is drawing the batteries waaaaayyyy down. Then also that same bank feeds half our house (including one fridge) so drawdown at anchor should be slightly improved.

Some of the question there was about cranking amps, but a bank of 4x GC2s should easily have enough headroom for that engine. (Double-checked with the Lifeline folks).

The Firefly does read technically nifty. I wonder if a golf cart version would similarly bring PSOC improvements to the table.

-Chris

[bobw100ton]

Lithium may be the future but I will take the FAA's position that thermal runaway is still a real possibility for now. Not all AGM's are equal, Lifeline and Odyssey stand out on performance and longevity, more than any other AGM battery we've worked with, unless you want flooded batteries which we find Rolls and Surrette have been exceptional contenders. Trojan 6vlt seem to be a good value as well. Like most things you get what you pay for. Longevity on a boat plugged into shore power 85% of its life is totally different from a cruiser who cycles their batteries daily. Gel batteries have the highest failure rate in the marine world due to the exceptional number of ways the charge algorithm can get corrupted from alternators, wind, solar, etc.. Unlike the other battery technologies, they have no tolerance for even slight overcharging, they will crystallize internally. This is an empirical opinion based on commissioning over 1500 cruising sailboats and trawlers of the past 25 years, not an analytical one. We are very fortunate to keep many of our customers through several boat iterations and benefit from a full performance review.... and getting the vicarious satisfaction of being part of their cruise....

[senormechanico]

We got ten years out of a Prevailer 8D.
Waiting to see how our LiFePo4's do.
So far 3 years or so and they're GOLDEN.

[Finistere]

Originally Posted by Maine Sail

Sounds like he had Deka GEL batteries not their AGM's..... This would not be out of the ordinary for a Deka GEL bank, but would be like winning the lottery for a Deka AGM, could happen but pretty unlikely.

The Deka AGM's are rated for considerably less deep cycles than the Deka GEL batteries, 370 cycles for Deka AGM and 1000 cycles for the Deka GEL...

You also may want to check out the May 2015 issue of Practical Sailor where PSOC (partial state of charge) use was examined in AGM batteries. Not all AGM batteries are built the same, and this article could pay for itself with one poor purchasing decision...

Fighting Sulfation In AGM's - Practical Sailor (LINK)




.

AGM group 31


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[GrahamHO]

I have had 2 yellow Optima AGM house batteries for 12 years and they are still going strong. My blue Optima starting battery only lasted 10 years and has been replaced with the same again. They are all on solar panels and my 80 amp generator uses a Next Step smart regulator. Other advantages are no fumes and no spill. They are installed under the quarter berths. I don't know the East Penn Deka batteries but I can vouch for AGMs and I guess price is the decider. With all rechargeable batteries it's important to keep them charged properly for long life. I would stay away from LI batteries in a boat. Steve Fossett's record breaking catamaran PlayStation (around 100') had a battery explosion causing a lot of damage while moored in Auckland NZ Viaduct Basin some years ago. I understand it was a LI battery. Saved weight though for the 24 hr speed record. I've had a lot of good experience with lithium ion TV camera batteries and there are very strict regulations about size etc when carrying them on board aircraft due to the possibility of fire.