ACDELCO Batteries, ACDM27DC

[Sonosailor]

I bought three new house batteries, giving up trying to keep a larger bank to make them last longer. No matter what, how babied, how lightly used, how often topped up and equalized, in the tropics, they die after year 4. I purchased them at Budget Marine, and they came with no information. (Choices are still somewhat limited - If you see it and you need it, you buy it)
I have challenged Budget personnel to find this, and have some hope they can.

I searched the Delco sites, found only one that allowed for contacts, and asked these questions. They said they are not authorized to provide the info, and that I should ask my nearest Delco Service Provider. Call me crazy, but I just don't think a Florida car dealership can tell me how to maintain marine deep cycle batteries with solar and wind in the deep, hot Caribbean. I'd rather have the email of the person at Delco they will ultimately have to call.
If you have these answers, please advise:

1.* What is the upper voltage setpoint that external alternator regulators, solar controllers, and windmill controllers should be set*up for for this brand and model?
2.* When the battery is set up for long-term storage (3-7 months), should the battery be disconnected, kept connected at the normal setpoint, or set to be maintained at a lower voltage?* Does the heat / temperature of the storage environment have any impact on these recommendations?
3.* What is the recommended, regular percent of discharge to optimize the lifetime of the battery?* 50%?
4.* If equalization of the battery is recommended from time to time, what are the recommendations; ie: what voltage, how long, and how often?
5.* What other recommendations does the manufacturer have for the new owner?
6.* What is the 21 hour amp-hour rating for this model?

I am currently in Carriacou, having fun; but likely undercharging my batteries due to a lack of information.

[motion30]

First you should know in spite of what it says on the label, a group 27 Delco battery is not a deep cycle battery. This could easily be your problem

[GordMay]

From the AC Delco FAQs page ➥
https://www.acdelco.com/auto-parts/c...--battery.html

MAINTENANCE TIPS
• Recharge battery after each use.
• Use a taper type charger set at 15.0 volts: For best results, a 10-15 amp taper type charger is recommended to recharge ACDelco Voyager models. Taper chargers help avoid overcharge by reducing the charge rate as the battery nears full charge. Follow instructions provided with the charger.
• Determine the charging time that will be required. Check the built-in indicator and charge the battery for at least the number of hours shown in the charging table (located in “Charging Instructions” section). If the green ball is not visible in the indicator after charging, tap lightly on top to dislodge trapped air bubbles that might keep the green ball from floating into view. For the most accurate results allow the battery to rest for 12 hours then measure battery voltage, 12.8 volts is fully charged.
• NOTE: A more definite charging time can be set if an accurate voltmeter is available for reading open circuit voltage
• DO NOT leave a battery connected to a battery charger after the battery is fully charged. Inspect battery every 2 hours when charging.
• Batteries charge more efficiently at 60–80 degrees Fahrenheit. Turn off charger if battery is hot.
• Keep battery in a cool place when storing for long periods (make sure battery is fully charged – a discharged battery’s electrolyte can freeze).
• Keep battery terminals clean and free of corrosion. To remove corrosion from terminals use a terminal brush.
• For maximum battery life where electrical requirements are high, separate starting and running batteries are recommended.

PROPER STORAGE
Fully charged ACDelco Batteries (OCV is ≥12.7) should be stored in an upright position at temperatures between 32°F and 70°F. When a battery is stored, a very slow chemical reaction takes place between the plate materials and the electrolyte, causing a slow discharge. This reaction, called a self-discharge, occurs more rapidly at higher temperatures. If an ACDelco Battery is completely discharged, the electrolyte will freeze when stored below 30°F. To prevent electrolyte freezing and battery damage, do not store ACDelco Batteries below 30°F if their OCV is less than 12.5 volts.

AC Delco Marine/RV Deep Cycle Instruction Sheet ➥ http://images.wrenchead.com/digi/DCL...structions.pdf

[john61ct]

Yes, can't make a silk purse out of a sow's ear.

There is a very short list of respected manufacturers of batteries truly suitable for deep cycling usage, and none are focused on big box retail nor the automotive market.

FLA is better value, more robust and longer lasting if you can go that way.

The best battery value by far is Duracell (actually Deka/East Penn) FLA deep cycle golf cart batteries, 2x6V, around $200 per 200+AH @12V pair from BatteriesPlus or Sam's Club. Deka labeled same batts also sold at Lowes.

Others include Rolls/Surette, Trojan, U.S. Battery, Crown and Superior.

If you truly need AGM, you will also need to spend more per Ah per year.

Odyssey, Northstar & Lifeline are the top makers there.

https://marinehowto.com/what-is-a-deep-cycle-battery

[Trifoiler1]

I replaced my 3 battery Group 27 deep cycle bank with 4 ACDM27DC batteries in parallel.
They have been horrible!

Right away they produced less power than the old 3 battery bank did.
My xantrex Link Pro says that I barely get 40AH out of the bank, from a full 12.8v charge before hitting 12.00V!

I have checked the batteries individually for faults.
I Rechecked all the battery connections with no issues.
Adjusted my charging parameters to 15V to no avail and no change.
Used a Promariner Prosport to fully charge each battery and condition them.

No change - minimal power output at 5-10A max draw at 12V
Not happy.

I am in the middle of nowhere in the Exumas.
How do I do a load test on the bank?
Or any other things I can try?

[Sternwake]

I've gone through many flooded 27's. No matter if they say 'deep cycle on them, they are not.

Getting good life from these is difficult, in deep cycling duty tremendous effort can be expended to learn what the battery needs, and it still will not live a long life when deep cycled regularly.

In my experience they need high absorption voltages, almost in the ridiculous range and the temperature compensating turkey baster style hydrometer will still reveal they are not fully charged, and its annoying as all get out, especially when an automatic charging source cannot easily be restarted and told to hold them at high voltage for longer.

I used to have to charge a group31 USBattery which is a pretty good marine battery, with my Solar setting at 14.9v, then bump my float voltage to 15.3v for the rest of the afternoon to even approach maximum specific gravity when cycled to 65% or less state of charge the night before.

Every 14 deep cycles it would require that same 'full' charge and then 45 minutes held at 16.2v for specific gravity to reattain 1.275+ on all cells. It was not a process I could do via solar alone in one day, but would have to switch all loads to a separate battery for overnight discharge, then let the solar loose at 16.2v on it the next day, then switch loads back to it and then recharge the other battery. Pain in the keester.

it took me a while to figure out the best regiment for this battery in my usage and I wound up getting ~500 deep cycles from it before it just irritated me to the point I refused to expend any more efforts into squeezing more life from it in deep cycle duty. i relegated it to very shallow/ light cycling ion the floor of a workshop, where it was OK for a few more years.

One of your 3 parallelled 27's could have a shorted cell. You might want to separate them and see what voltages they seek. if one battery is ~ 2 volts less than the others remove it from service.

If you are stuck with group 27 size, your only hope of getting a true deep cycle lead acid battery is with an AGM, the 27 flooded marine dual purpose batteries are just not very capable and have extremely poor charge efficiency factors.

Mainesail found one so called 'deep cycle' group 27 had thinner plates, and one less of them, than the starting battery g27 from the same sticker slapper.

Anybody who believes, that a regular car size battery that has a deep cycle sticker on it, is an actual deep cycle battery, should be slapped upside the head with the following link:

https://marinehowto.com/what-is-a-deep-cycle-battery/

Any battery vendor who says a 12v flooded Marine/rv/trolling battery is a true deep cycle battery, should be kicked in their nether regions.

One can deep cycle a starting battery, it does not mean it is a deep cycle battery.

I paid significantly more for G27 and g31 TPPL AGMs but I get incredible service from them and have lots of confidence in their ability to support my needs and desires, And I can charge them properly.

That 'properly' means a charging source that can feed them high amps from their most depleted state, and hold absorption voltage until amps taper to 0.5% of capacity.

[Sonosailor]

Rest of my saga: Budget Grenada was no help, first offering to assist, then responding to no emails. I came to the same conclusion as the assistance given, that the batteries were not deep cycle. I was now in Martinique, and found another sailor who needed a start battery, and traded one of these batteries for some other parts, at a great loss. I then had room to purchase three French 74AH batteries, but with posts, no screws. The work to install these without screws was annoying, and makes me think it is time to simplify the battery wiring plans anyway, as we need to replace these bastards every 4 years. At least I was able to continue to travel for the season.

Finally returning to Grenada, I got a run-around for two days after dropping the batteries off, then got the refund on the third. What a lot of annoyance for mislabeling batteries. It would have been a small thing for those who do not sail far from their home port. Thanks for the info and support.

[Trifoiler1]

Thanks STERNWAKE!

I have bumped up my recharging voltage to ludicrous range and Ill limp home using your 14 day blast em technique.

SONOSAILOR how old were the batteries when you returned them? I am impressed that you got a refund!

[Sonosailor]

Trifoiler1: I purchased at the end of November. Budget's battery stock/price sticker, and my sales receipt said that each was a 100AH battery. I started asking questions of Budget almost immediately, and quizzed Delco by phone and email, with poor results. I, with the assistance if this forum came to the conclusion that they were not deep cycle batteries. I began asking what they intended to do for me, and started to spray their staff with the emails. The manager finally got back to me near the end of January and said first that he'd look into it, then later that he found the error and corrected the listing and battery description. I worked to get continued communication with him, offering to sell these up-island to people who needed start batteries, and asked him what discount he would allow so that I could move them. No responses. I think, in the end, his embarrassment at his poor handling of the case worked for me, when I returned and again started the badgering in mid-March. Hey, he still got full price for the one I traded, even though I lost on it. I also store my boat 200' away, buying chain, pumps, parts, bottom paint, etc., on a regular basis.