My own fault!

I've been boating for over 30 years. Ronaldous Maximous was president!
Anyway, I've always been into routine maintenance. I believe, it's better to do a little work now and spend a little money now vs. a bunch later.
I just took possession of my boat in May of this year. I did check the oil once a week, at least every 2 weeks. Never checked the water in the batteries. The previous owner stayed plugged in, a sure sign that the batteries need topping off on occasion. Hauled the boat for painting and such last week. Just got around to checking the water in the batteries. Way low! The cells were exposed. Now I have 2, very expensive 8D's that ran for an undetermined amount of time with the cells exposed. I can see batteries in my future. For a 15 minute job to check the water, it's going to cost me big time. Maybe they were already toasted? At least I would have had a shot.
That's a 1 time per month thing for me, usually. It certainly will be from now on!

Sorry to hear that! Heck with the price of 8 Ds.... removing 170lbs per battery concerns me far more. Ya got a few young strong guys hanging around your boat?

They can be durable. Top em up and see. Also why I hate 8ds. I moved them once, never again.

I just replaced 2 4Ds in my boat. Somewhat lighter than 8Ds by about 30 pounds. At least mine are in an easily accessible location. I feel for you.

Hi Molly:

Who are you having paint your boat down there in Punta Gorda?

We researched the heck out of the Firefly batteries before we bought them. Among many other advantages, they have no water levels to check. We have six, and this bank is both our house and starting battery system.

https://www.bruceschwab.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

Just another thing to consider before buying more lead acid batteries.

Pea

I hate 8D, I personally have no use for them.
When are we going to get away from thinking bigger batteries are better batteries.

Group 31 are good for me for starting.
I bought an 8D years ago and it disintegrated in about 2 years. Plates turned into mushy chunks.

One guy says 8D are durable. The other guy calls them mush.

I had 8 of those big boys in a previous boat. They started both Jimmys, both nasty gensets and also provided house power through a 3kW inverter powering stove, fridge, freezer, water heater, etc.

They were old and hugely neglected by the PO. However I topped them up with water and they worked like champs for years.

So my impression is that 8Ds are robust, almost industrial grade. I say just continue to work them hard until absolutely dead, before spending many Boat bucks on new batteries.

PS: there has got to be someone knowledgeable here who can comment on plate thickness or other technical aspects of a typical 8D

There are quality batteries and junk batteries in every group type. I have never seen exposed plates come back no matter how high the battery quality. I use only commercial grade batteries, but that’s easy for me, I drive by Dyno Batteries every week. As for group 31 vs 8d, if you match CCA then there is no issue. Yes 8d’s Are heavy, if you are doing the lifting then you might be better off with g31’s. If you pay to have batteries installed you might be better off with 8d’s.

You have nothing to loose so refill them with demineralized water, charge them and test them. I did the same with my group 31. I was expecting them to be toasted but after refill and recharge, I tested them and they still gives me 20h of autonomy at 50% discharge, less but not so far from when they were new.

L

Just a thought. Make sure you’re not boiling your batteries because of a faulty battery charger. Like I did recently!

8D are not deep cycle, unless they are deliberately designed as deep cycle.
They are nothing special, simply big starting type batteries..
They are big and heavy, so back breakers, you risk your health moving them.
If I had them and they were bad, I would not replace with new 8D.
I personally have no use for them.
The one I bought years ago, I got from Sams Club and it had a Champion sticker on it.
It was very disappointing to see it turn to mush in 2 years.
Opening up the caps and looking inside, the plates had disintegrated.

Molly, I had the same problem when my boat was "new to me". I topped up,added a desulphating potion,and recharged. One did not respond, one lasted a year, another lasted 3 years. You can get a range of results,but it`s worth a try to save them. A simple inexpensive hydrometer is useful for testing them after recharge.

Work smarter
Not harder
If you hurt your back replacing batteries you are out of business for too long.
I Pay My Lawn Service Guy $50.00 to lift the old one out and the new one in.
5 Minutes Work
He’s happy and I don’t have a hurt back. [emoji41]

sdowney717 said:

8D are not deep cycle, unless they are deliberately designed as deep cycle.
They are nothing special, simply big starting type batteries..
They are big and heavy, so back breakers, you risk your health moving them.
If I had them and they were bad, I would not replace with new 8D.
I personally have no use for them.
The one I bought years ago, I got from Sams Club and it had a Champion sticker on it.
It was very disappointing to see it turn to mush in 2 years.
Opening up the caps and looking inside, the plates had disintegrated.

Click to expand...

8D is only a group size. They come as starter batteries or as deep cycle. You can buy cheap crappy 750 CCA versions or you can buy high quality 1275 CCA versions. You might not have a use for them but that doesn’t mean that they are not viable for others.

tiltrider1 said:

8D is only a group size. They come as starter batteries or as deep cycle. You can buy cheap crappy 750 CCA versions or you can buy high quality 1275 CCA versions. You might not have a use for them but that doesn’t mean that they are not viable for others.

Click to expand...

Like I said, if it is was me, I would not buy another one. AS I SAID in my post.
And I never did buy another one.

The group 31's I have are 950 CCA. Way more amps than I need.
Comes in 2 versions
https://shop.advanceautoparts.com/p...battery-group-size-31-950-cca-31p30/2100010-P

https://shop.advanceautoparts.com/p...OaLw8awFykvWR-qWtN8aAkLoEALw_wcB&gclsrc=aw.ds

Miz Trom said:

Hi Molly:

Who are you having paint your boat down there in Punta Gorda?

We researched the heck out of the Firefly batteries before we bought them. Among many other advantages, they have no water levels to check. We have six, and this bank is both our house and starting battery system.

https://www.bruceschwab.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

Just another thing to consider before buying more lead acid batteries.

Pea

Click to expand...

Who did you purchase yours through? Their so-called dealers sure aren't promoting them much and at least one dealer claims they're on backorder and he doesn't have any.

I use these to reduce battery watering needs. I watch them closely but only have to add water half as much.

Nice tip, Al!

I have Water Miser Caps on one 8D. Not quite as miserly as me, but helpful. There are bayonet adapters to fit certain batts, incl mine which is a Century/Yuasa. I had to raise the height of the cover over the batt box to accommodate cap and bayonet.

Why not use an AGM battery? I have had mine in for 9 years now, replacing two year old wet cell 8D's. Price were comparable.

Molly said:

I've been boating for over 30 years. Ronaldous Maximous was president!
Anyway, I've always been into routine maintenance. I believe, it's better to do a little work now and spend a little money now vs. a bunch later.
I just took possession of my boat in May of this year. I did check the oil once a week, at least every 2 weeks. Never checked the water in the batteries. The previous owner stayed plugged in, a sure sign that the batteries need topping off on occasion. Hauled the boat for painting and such last week. Just got around to checking the water in the batteries. Way low! The cells were exposed. Now I have 2, very expensive 8D's that ran for an undetermined amount of time with the cells exposed. I can see batteries in my future. For a 15 minute job to check the water, it's going to cost me big time. Maybe they were already toasted? At least I would have had a shot.
That's a 1 time per month thing for me, usually. It certainly will be from now on!

Click to expand...

Whatever state the batteries are in, it did not happen in the last two months.

Fill them up, charge and hope for the best.

Firefly Batteries

Miz Trom said:

Hi Molly:

Who are you having paint your boat down there in Punta Gorda?

We researched the heck out of the Firefly batteries before we bought them. Among many other advantages, they have no water levels to check. We have six, and this bank is both our house and starting battery system.

https://www.bruceschwab.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

Just another thing to consider before buying more lead acid batteries.

Pea

Click to expand...

I'd love to hear your experience with Firefly batteries so far.
Maybe even anew thread??

Richard

NAPA frequently has 8D on sale , 5 years at least with modest care.

I would adjust the float voltae from the 12v charger , it would seem to be set too high.

Most batt water needs come from hard charging with a big alt.

Dockside 120v charging ,every month should easily be enough checking.

One problem I have found with older , dumber chargers is they will sense a discharge , toilet or fridge ,whatever, and then switch from float to full charge to remake the 100% full.. This cycle a few times a day eats water.

A digital Volt meter is frequently free at discount sellers , certainly always under $10.. You might monitor the shore charge during the day,

Top them off....as others have said, don't condemn them on principal.



Conall

Thanx for all the responses.
My thoughts are sort of obvious. Top them off and wait and see. I may get another season or two out of them. I spend a lot of time on the hook, so I'll find out relatively quick. With the fridge and lights, TV and the like. I will have to run the genny anyway, for some reason power boats usually have electric stoves. I will charge the batteries at least once a day.

As far as batteries go, I would go with lead/acid. Simply put, it's way cheaper. AGM would be 4x's the price. Firefly, foam carbon, only comes in size 31 and 110 AH for $500. I would need 8 - 10 to match the AH's I have. Way too much! I need around 800 AH for a boat my size. Lead/Acid are cheap and reliable. If you go up a few levels from COSCO, a typical lead/acid battery will last 7 years. Of course, checking the water level is key.

I do agree with one of the earlier posts. Since it is a new boat for me, I should check the charger and make sure it's not cooking my batteries. 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. Plus a couple of solar panels. Had it my last boat. I could spend 48 hrs on the hook, with fridge, lights, TV and stuff without running the genny. Had a propane stove though. Maybe that's another project?

Aren't boats wonderful? You spend way too much money for the boat, then continue the spending until you sell it. Then start all over again when you get the next boat.

Buddy

Who did you purchase yours (Firefly batteries) through? Their so-called dealers sure aren't promoting them much and at least one dealer claims they're on backorder and he doesn't have any. - BandB

Click to expand...

Hi BandB:

We bought the first six from Fisheries Supply in 2017, had them delivered to our home, and then drove them up to Gainesville, FL to have them installed on our new boat. They were all tested and in pristine condition when we delivered them. (www.fisheriessupply.com)

A year later, the casing of one of the batteries was cracked when our surveyor inspected the boat. From its appearance, we think it was dropped before installation. The one with the broken casing was still functioning during the lake test of the new boat, but on the recommendation of our surveyor and marine electrician we decided to replace it.

We bought a replacement Firefly from Coastal Climate Control www.coastalclimatecontrol.com) last month. We have not installed it yet, but the boat is not yet in use and installing the new one is on our to-do list.

Both websites show they are currently out-of-stock/unavailable. I think they are becoming popular because it takes time to find them. The key is to check weekly on the websites of sellers, and order immediately when you see that they are available.

We are hoping that they live up to their specifications, which are remarkable when compared to LA and AGM batteries. A few cruisers have been using them now for a couple of years but we have only seen one report over on Cruisers Forum, and this report primarily discusses a Balmar smartgauge...
Interesting behavior - Firefly batteries, Balmar Smartgauge, small solar panel - Cruisers & Sailing Forums

Regards,
Pea

Miz Trom said:

Hi BandB:

We bought the first six from Fisheries Supply in 2017, had them delivered to our home, and then drove them up to Gainesville, FL to have them installed on our new boat. They were all tested and in pristine condition when we delivered them. (www.fisheriessupply.com)

A year later, the casing of one of the batteries was cracked when our surveyor inspected the boat. From its appearance, we think it was dropped before installation. The one with the broken casing was still functioning during the lake test of the new boat, but on the recommendation of our surveyor and marine electrician we decided to replace it.

We bought a replacement Firefly from Coastal Climate Control www.coastalclimatecontrol.com) last month. We have not installed it yet, but the boat is not yet in use and installing the new one is on our to-do list.

Both websites show they are currently out-of-stock/unavailable. I think they are becoming popular because it takes time to find them. The key is to check weekly on the websites of sellers, and order immediately when you see that they are available.

We are hoping that they live up to their specifications, which are remarkable when compared to LA and AGM batteries. A few cruisers have been using them now for a couple of years but we have only seen one report over on Cruisers Forum, and this report primarily discusses a Balmar smartgauge...
Interesting behavior - Firefly batteries, Balmar Smartgauge, small solar panel - Cruisers & Sailing Forums

Regards,
Pea

Click to expand...

I find it very curious that all of their dealers have none available right now.

I was in fisheries supply on Sunday. They had two of the firefly sitting on the show room floor. Don’t know if they are spoken for.

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

Voltage doesn't tell much but a Link, or any brand of SOC , state of charge , is probably the best $150 you can spend.

I prefer the Bogart , but there are lots of brands.

​

Bogart TM 2030A TriMetric AH/Volt Meter
$143.97
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TriMetric Model Descriptions - Bogart Engineering

TriMetric Model Descriptions - Bogart Engineering

Measures battery % full, based on amp hour measurements for accurate information on state of charge (SOC). This method is more accurate than monitors that ...
Bogart Engineering Trimetric Battery Meter Kit | Backwoods Solar

Bogart Engineering Trimetric Battery Meter Kit | Backwoods Solar


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