My own fault!

[Heron]

. My initial reaction is that when you leave a boat plugged in, you loose water and cook the batteries, no matter what. I plug in when necessary and unplug when not needed. If I am plugged in for any length of time, I will turn the charger off. I would rather monitor the voltage.

One of my future projects is to install digital voltage monitor, maybe a LINK system.
Buddy

Not necessarily with the correct smart charger set to the correcty battery profile. My Sterling 40 amp charges my 4 battery Golf Cart bank at 13V when idling. A number sufficiently low to prevent boiling and keep just above a full charge voltage of 12.7. A friend juat had a charger go awry and cook a 31 case battery . No great loss, but it tuned him into the charger failure.. Having monitoring equipment is very helpful. I can hang for 2 days on the hook and not go below 50% capacity and still keep the beer cold...

 

[Andy G]

As far as batteries go, I would go with lead/acid. Simply put, it's way cheaper. AGM would be 4x's the price.

I am surprised to hear you say that.AGM & wet cell battery prices are much of a muchness over here, and our marine parts prices are almost always more than you pay over stateside. The great things with AGM's is the 'set & forget' feature, that is assuming your charger system is set up properly.

 

[DDW]

You should fill them with water and do an equalize charge on them, then see what you have.

The big claim of Fireflys is their ability to operate at a partial state of charge for long periods without sulfation. This has been verified by many users and a few independent tests. Probably more important on a sailboat than a powerboat.

The company that owns the rights is a peculiar one, and doesn't seem to have the ability to ramp production to match demand. They also have a large capacity 2V/4V version for building large banks. Like LiFePo4, their cost is high but their lifetime cost may be lower than flooded cells.

 

[Molly]

Update.... Had to use 2 gallons of distilled water! WOW!
I would be surprised to get another season out of these. We'll see. For now, they start the boat and that's all I need for now. In October she goes back in and then we will have the real test. At 160 #'s each, that will be fun anyway!

 

[Lou_tribal]

Update.... Had to use 2 gallons of distilled water! WOW!
I would be surprised to get another season out of these. We'll see. For now, they start the boat and that's all I need for now. In October she goes back in and then we will have the real test. At 160 #'s each, that will be fun anyway!

You may be surprised, I use 1 gallon and half in mine and still not too bad.

L

 

[dhays]

Update.... Had to use 2 gallons of distilled water! WOW!
I would be surprised to get another season out of these. We'll see. For now, they start the boat and that's all I need for now. In October she goes back in and then we will have the real test. At 160 #'s each, that will be fun anyway!

I’ve mentioned it before, but when I had wet cells I put the dehumidifier drain hose into a water bottle in the sink. Every time I went aboard I would use that to top off the batteries. It quick and convenient.

Now that my batteries are not in a convenient location, I use AGM.

 

[BandB]

You should fill them with water and do an equalize charge on them, then see what you have.

The big claim of Fireflys is their ability to operate at a partial state of charge for long periods without sulfation. This has been verified by many users and a few independent tests. Probably more important on a sailboat than a powerboat.

The company that owns the rights is a peculiar one, and doesn't seem to have the ability to ramp production to match demand. They also have a large capacity 2V/4V version for building large banks. Like LiFePo4, their cost is high but their lifetime cost may be lower than flooded cells.

And there you've hit upon the two big reasons not to purchase FireFly's. First is cost, but the larger one to me right now is availability. Eventually, they're going to fail and if you need to replace one or four or eight, will you be able to quickly get a replacement? Will it be same day? We haven't encountered a surprise yet on a boat, perhaps because we monitor and we replace before they reach that point, but every car battery I've ever replaced has come as a surprise. Right now I'm concerned about what is going on and whether the company is dying as not one of their regional dealers appears to have any available. Perhaps it's the distributor. I don't know, but lack of product availability reflects some sort of serious problem.

 

[Molly]

Question.
How do you know if your charger is over charging? Allegedly, my charger is at full charge until 80/85% is reached. Then it goes down in charging power until 95% is reached. Then it will hit a trickle charge, There is a battery isolator, which is supposed to make sure the weakest battery is charged first. I think that means, it will switch back and forth to always be charging the weakest battery. I would think, if that trickle charge part is still too powerful, that's when you cook the batteries. There is a digital read out on the charger, not sure what I'm looking at.

 

[dhays]

Question.
How do you know if your charger is over charging? Allegedly, my charger is at full charge until 80/85% is reached. Then it goes down in charging power until 95% is reached. Then it will hit a trickle charge, There is a battery isolator, which is supposed to make sure the weakest battery is charged first. I think that means, it will switch back and forth to always be charging the weakest battery. I would think, if that trickle charge part is still too powerful, that's when you cook the batteries. There is a digital read out on the charger, not sure what I'm looking at.

You need to find the manual for the charger and read it carefully. I don’t understand batteries but my understanding is that your charger should initially bulk change at the max amount of amps that your batteries can handle (based on the battery manufacturer charging instructions). Once the batteries reach the absorb voltage (again specified by the battery manufacturer) the batteries are held at that voltage for either a specified period of time or until the amps required to maintain that voltage drop to to a given value. Then your charger holds the batteries at the batteries float voltage. This float will gradually completely recharge the batteries.

So it isn’t that the % numbers you gave are wrong, but they are secondary to the amps and voltages used for the three stages of charging. Again, find out what the ideal battery charge profile should be and then make sure your charger is programmed to provide that. I wouldn’t necessarily trust that they PO had it setup correctly. I know that I’ve setup chargers incorrectly in the past.

It is easy to check if the charger is holding the batteries at the proper voltage just by using a multimeter at the batteries. So, if your charger is programmed to hold a float voltage of 13.4v for example, you should see 13.4v at the battery. If you see more than that, then there may be a problem with your charger.

Now, if your charger is older and can’t be programmed for your specific battery type or can’t handle three stage charging you may want to consider upgrading the charger at some point as it will save you money on batteries in the long run.

Of course, you should ignore anything I post about batteries as I am really ignorant on the topic.

 

[rolomart3]

I replaced 3 8D batteries with group 24 batteries. Three group 24 batteries fit perfectly inside the 8D battery box and are much lighter than even a group 31. I can change them myself. I manufactured short cables to connect the batteries inside the boxes.



It does add additional cells to check for water level but I can change these batteries myself.

 

[NightCrawler]

Just a thought on good/bad battery experiences. Last summer we replaced our house batteries. 4 6v deep cycle Duracell 'brand.' They looked brand new (no date sticker on them) but were very weak. Battery delivery guy said they had a mountain of them at the shop. Said they think they are counterfeit copies. This is a huge issue in automotive parts and my guess is that -insert brand name- item that was total crap, very likely was a cheap import copy.

 

[Rosborough 35]

I was getting about a 3 to 4 year life out of a set of 2 flooded 8D batteries (West Marine Dual-Purpose, $500 each). About 5 years ago, I decided to try a Lifeline Group 31 AGM battery for my bow thruster. That worked out well, so 3 years ago, I switched from standard flooded 8D batteries to Lifeline AGM 8D batteries (Stored Energy Products, $650 each). The bow thruster battery is still working well after 5 years and the two Lifeline 8D batteries are 3 years old and still performing like new. I don't think I would have gotten a 5 year life out of a flooded battery for the bow thruster. For the $150 per battery difference in price for the 8Ds, I will definitely stick with the Lifeline AGM batteries.

When I installed the new Lifeline batteries, I also switched from a ProMariner ProSport20 Plus charger to a Blue Seas P12 charger. I like the monitoring ability with the Blue Seas charger.

 

[Oldsarge]

My sailboat had a couple of 8Ds in it when I bought it. It was an old sailboat and the
8D's wouldn't accept a charge. I bought several Optima Blue top's, and they are pretty
expensive, but one is still good after 8 years, and one has a bad cell but will still crank
out 100 amps at 9 volts. I have a yellow top deep cycle/cranking that is at least 6 years
old and still good. I kind of mix and match my dual banks and recently had to replace a cheaper deep cycle that had a bad cell, but it was about 5 years old. They get charged by, solar, occasionally by charger and sometimes by engine generator. The solar has a regulator and the engine generator has a Balmar ARS-4 regulator. I use my diesel a lot
on my sailboat, so it is sort of like I have a sailing trawler. What can I say?

 

[Molly]

I will be down there with a voltmeter. All I know is those 160# babies are also inside a box with 6" high sides on them. I dread getting those things outta there! Crowbars, pipes and pulley's. Or a phone call to the marina!

 

[twiisted71]

I went through this a few years ago (Cape Coral with a 34 Mainship MkIII). I used my 2 big 8d batteries as trade-ins and went to the golf cart place on 41 in N Ft Myers and got 4 6 volt golf cart batteries. I think they were called 105s (?). Put them in a nice snazzy new battery box and ran them as house batteries. They are WAAAAY easier to handle. I then put in an Odyssey group 31 or 65 (can't remember exactly anymore!) starting battery. I had a small standard car size battery for my genset starter (but it also had an optional manual crank I could use if everything else was dead and couldn't be shunted to start the main.

*sidenote* does anyone still offer a handstart on an "installed" watercooled genset?

 

[rgano]

Refill the 8Ds and place them on a battery minder /desulfator for a couple of weeks. I love my AGMs with an appropriate charger. Never going back to worrying about watering batts.

 

[Choices]

We just bought 3)8D AGMs and a small 27 for the genset.

I bought from an industrial supplier that supplies batteries for substations, generators, solar farms, and ups systems.

Paid less than $375 for each 8D, and gave two short stocky guys $100 to remove and set them all.

I also made a small voltage display above the lower helm for each battery to give me an idea at a glance of what's happening.

It is on our blog, grandbankschoices.

 

[FF]

For any WLA batt the weight of lead , is the size of the "gas tank".

Sure, most diesels will start with a pair of GP 31 , so there a great choice.

For house service only built deep cycle batts will last and they must be watered.

The amount of water the house batts will require mostly depends on how often and how deeply they are discharged.

Sitting as a dockside cottage requires little water , a daily run down from 90% SOC to 50% SOC will require much more , perhaps weekly watering.

WLA is one example of bigger ( heavier ) IS better