What type of battery is this?>

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SILENTKNIGHT

Senior Member
Joined
Oct 19, 2018
Messages
192
Location
United States
Vessel Name
STELLA DI MARE
Vessel Make
2006 MAINSHIP 34T
Can someone tell me if this is a sealed battery or a flooded? I see no cap covers to open and check water levels. The battery is used for my generator and the sides are warm and bulbing out, so i disconnected it. I thik it should be replaced. ?:confused:
The battery date is Feb 2018
24M series
 

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Looks like a sealed lead acid Group 24 battery. These are usually 3 year non serviceable batteries. They are made cheap and considered disposable. They don’t like being on battery maintainers.
 
It's past it's use by date. I'd never use a sealed battery in a boat, you need to be able to check and add water. Ok for cars though. If your want to stay with lead acid, make sure the new one has caps. And if it's hard to get to check, look at a watering system like the Flo-rite. Makes adding water simple, just squeeze a bulb like an outboard motor fuel line.
 
There are many boats using sealed batteries. AGMs are lead acid by design too, sealed at that. We've got three different groups of sealed batteries, no issues. Tens of millions of sealed batteries are made every year and if treated right last a long time.

Without knowing about the conditions under which this cited battery tried to survive, a good review of the charging system, routine checks and accessibility for maintenance may be warranted.
 
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If the battery is HOT bulging that is all you need to know. Replace the battery. I have a sealed group 31 for my start battery that feeds my genset and motor. They are connected with an ACR and monitored through my DC panel that has three inputs for voltage sensing.
 
I detected a strange smell in our house. Thought it was a dead mouse. Couldn’t find it. Wife could not smell it. Next day it was worse and I began my hunt again. By 11PM I was frustrated enough to call the fire department and ask what to do. They said they would “send a man” to investigate. At 11:15PM, sirens blaring, lights flashing, arrived two fire trucks, two police cars and an ambulance! After waking the entire neighborhood they located the source. It was a computer backup battery overheated and swollen. They picked up with fireproof gloves, tossed it on the front lawn and gave it a foam bath. Don’t think twice about discarding a hot battery.
 
Hot batteries can be a big deal

In Vancouver B.C. there have been a couple of fires started by Ebike batteries. In some of these fires there have been loss of life. So ya, batteries can be a big deal, especially if the boat is unattended and the battery goes on fire in the engine room. You can think of all the bad things that can happen with an unattended fire that happens in the engine room. Throw the battery out.
 
Can someone tell me if this is a sealed battery or a flooded? I see no cap covers to open and check water levels. The battery is used for my generator and the sides are warm and bulbing out, so i disconnected it. I thik it should be replaced. ?:confused:
The battery date is Feb 2018
24M series

It has a part number right there on it. Search on that part number.
https://duckduckgo.com/?q=SLI24MHP

Honestly, the first thing worth doing when trying to debug issues is a SIMPLE SEARCH ONLINE with whatever part or model numbers you can find.
 
That battery is toast. Toss it.

Just by chance I happened to have another battery issue this past weekend and I made a short video. One of the best tools I have purchased recently has been a Thermal Camera. The one in this video is a Hikmicro B1L. $399 on Amazon. Its already uncovered 3 serious issues and about 5 more issues that need to be addressed. All electrical.

In the video you can see an odd hotspot right through the case.



https://youtu.be/gQKYiHhxBos
 
The group 24 batteries are somewhat inexpensive for AGM type. Just plan on replacing it every 3-4 years and you will be in good shape.
 
When you run the battery part number on GOOGLE, it shows up as "SLI24MHP Duracell Ultra BCI Group 24M 12V 800CCA Flooded Starting Marine & RV Battery".

Computer search engines can solve a lot of questions.
 
Lots of batteries die without getting hot and bulgie. I think you need to do some more trouble shooting before you replace the battery and have the new one go hot and bulgie. My first guess would be a charging problem; and within that category I’d be suspicious of the generator’s alternator…..specifically the regulator. Sounds like it may have failed causing the alternator to run-away and cook the battery.
 
In the video, there seems to be an exhaust pipe running right the hot battery. The battery has a major hot spot across from the hot spot on the exhaust pipe Can mounting an electrical device with a plastic case next to an exhaust pipe be optimal?

But I do like the camera. I wonder if they make a USB version.
 
In the video, there seems to be an exhaust pipe running right the hot battery. The battery has a major hot spot across from the hot spot on the exhaust pipe Can mounting an electrical device with a plastic case next to an exhaust pipe be optimal?

But I do like the camera. I wonder if they make a USB version.

The exhaust location for the generator and batteries are definitely not ideal. However the exhaust tube temp is usually just above ambient and only slightly warm. Its a small 2 cylinder Westerbeke with quite a bit of water flow. When I redo the batteries the house bank will likely be moved and a few things rearranged.

The batteries that failed were from 2016 so I really cant complain too much and I dont think they failed prematurely. The thing I never liked about the tightly wound spiral cell Optima batteries is how they fail. When they go they seem to nearly melt down.

They do make a Thermal Camera that attaches to your cell phone. I actually have one. Its a huge power hog on your phone and the picture isnt quite as good. But its still quite useful.
 
https://www.batteriesplus.com/productdetails/battery/marine-and-boat/deep-cycle/sli31mdp

SLI31MDP Duracell Ultra BCI Group 31M 12V 700CCA LA Flooded Deep Cycle Marine & RV Battery - $144.99 minus 10% discount nearly always available. $27.00 Core Deposit refund. Net cost $130.59 ea. + tax

I carry 4 in parallel for house bank. Also, they're hooked into starters on twin engines.

Have a 24 LA starter batt hooked onto genset.

27 LA isolated starter batt for emergency in separate black box, 100% charged.

Inexpensive, last for years, easy to care for, replacements always available, not too heavy, reasonable power supply.
 
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https://www.batteriesplus.com/productdetails/battery/marine-and-boat/deep-cycle/sli31mdp

SLI31MDP Duracell Ultra BCI Group 31M 12V 700CCA LA Flooded Deep Cycle Marine & RV Battery - $144.99 minus 10% discount nearly always available. $27.00 Core Deposit refund. Net cost $130.59 ea. + tax

I carry 4 in parallel for house bank. Also, they're hooked into starters on twin engines.

Have a 24 LA starter batt hooked onto genset.

27 LA isolated starter batt for emergency in separate black box, 100% charged.

Inexpensive, last for years, easy to care for, replacements always available, not too heavy, reasonable power supply.
Just to be clear to those who might care, this Duracell battery is not a true deep-cycle battery. It is a dual purpose battery. It is primarily a starting battery that can be used as a house battery. These batteries serve some boaters' use cases well but a bank of true deep-cycle batteries can start any engine all day long.
 
Just to be clear to those who might care, this Duracell battery is not a true deep-cycle battery. It is a dual purpose battery. It is primarily a starting battery that can be used as a house battery. These batteries serve some boaters' use cases well but a bank of true deep-cycle batteries can start any engine all day long.

Thanks Jack. That is correct! In that, there are some much more rugged, larger sized, considerably added weight, greatly increased power storage "Deep Cycle" battery makes, types and charging/use-systems to chose from. At comparatively greatly elevated costs.

However, that cost-rise may be triple, quintuple or even much higher by taking into account the numerous additional added costs for high tech batteries requiring sophisticated charging apparatus and complicated use-systems. Although there are some notably more expensive deep cycle, house-bank battery setups that seem anecdotally to last long durations, there is also too often anecdotal reports on setups [of many different expensive battery types, charger configurations and DC power use-systems] that do not last any longer than my inexpensive type 31, LA, distilled water, wet-batt house bank set up. Life span on my batt set up goes from a low of of six years to a high of ten... before I need to replace only all four of the house bank batts. 14 years ago my cost was well under $500. Next replacement [7 +/- years since last replacement] the cost should still be under $700. Takes me about four hours to accomplish total replacement]. Boat house bank batt cost per annum: $100 +/- !!

For further clarity... Due to my many decades [1950's, 60's onward] of anchor out pleasure-boat-play/cruising to points of interest and short term liveaboard while at anchor or mooring: I am enormously conservative in use of DC power while away from dock AC power. So much so... that while staying aboard with no battery charging applied my house bank power storage in this simple and inexpensive house bank set up can last up to 72 hours before hitting the 50% charge level; that IMO demands a full charge level to be regained [I actually like to recharge when batts hit the 60% level]. On my boats, while away from dock, house bank recharging is achieved by either flipping on the charger breaker while running the gen set [to cook, cool the fridge and/or watch TV as well as charging phones/computers], charging also automatically happens while cruising [or running the starboard engine solo]. Also have small solar panel hooked into gen set starter batt to make sure that stays 100% charged.

So... the point I'm trying to get across to all levels of boaters [especially the pleasure boaters who are weekend warriors with occasional multi week or (even multi month) stay aboard cruises:

It is not absolutely necessary to spend thousand$$ of dollars to install or to get upgraded into the most advertised new-age, high tech DC battery and charger galore, use-complicated house bank, deep cycle battery $y$tem on your boat. Unless of cour$e you feel like doing $o!

In New England waters during the 1950's 60's mentioned above my family of five would cruise for weeks on end with just a few large LA wet batts keeping us well powered for DC electric needs. Much fun was had by all! Only notable difference aboard our boats, in comparison to yester year, is that now we have a genset and solar panel at our avail.

I don't want anyone to get me wrong... If several thousand$$$ are spent to install the most advanced battery package on a boat - then living aboard can be made to seem DC powered enough to resemble the nearly unlimited electric comforts of home. However, that's not my game plan for pleasure boating and for the relaxation offered by inexpensive, easy to deal with battery and charger systems.

Simple is as Simple Does!! :thumb: :dance: :speed boat:
 

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Thanks Jack. That is correct! In that, there are some much more rugged, larger sized, considerably added weight, greatly increased power storage "Deep Cycle" battery makes, types and charging/use-systems to chose from. At comparatively greatly elevated costs.



However, that cost-rise may be triple, quintuple or even much higher by taking into account the numerous additional added costs for high tech batteries requiring sophisticated charging apparatus and complicated use-systems. Although there are some notably more expensive deep cycle, house-bank battery setups that seem anecdotally to last long durations, there is also too often anecdotal reports on setups [of many different expensive battery types, charger configurations and DC power use-systems] that do not last any longer than my inexpensive type 31, LA, distilled water, wet-batt house bank set up. Life span on my batt set up goes from a low of of six years to a high of ten... before I need to replace only all four of the house bank batts. 14 years ago my cost was well under $500. Next replacement [7 +/- years since last replacement] the cost should still be under $700. Takes me about four hours to accomplish total replacement]. Boat house bank batt cost per annum: $100 +/- !!



For further clarity... Due to my many decades [1950's, 60's onward] of anchor out pleasure-boat-play/cruising to points of interest and short term liveaboard while at anchor or mooring: I am enormously conservative in use of DC power while away from dock AC power. So much so... that while staying aboard with no battery charging applied my house bank power storage in this simple and inexpensive house bank set up can last up to 72 hours before hitting the 50% charge level; that IMO demands a full charge level to be regained [I actually like to recharge when batts hit the 60% level]. On my boats, while away from dock, house bank recharging is achieved by either flipping on the charger breaker while running the gen set [to cook, cool the fridge and/or watch TV as well as charging phones/computers], charging also automatically happens while cruising [or running the starboard engine solo]. Also have small solar panel hooked into gen set starter batt to make sure that stays 100% charged.



So... the point I'm trying to get across to all levels of boaters [especially the pleasure boaters who are weekend warriors with occasional multi week or (even multi month) stay aboard cruises:



It is not absolutely necessary to spend thousand$$ of dollars to install or to get upgraded into the most advertised new-age, high tech DC battery and charger galore, use-complicated house bank, deep cycle battery $y$tem on your boat. Unless of cour$e you feel like doing $o!



In New England waters during the 1950's 60's mentioned above my family of five would cruise for weeks on end with just a few large LA wet batts keeping us well powered for DC electric needs. Much fun was had by all! Only notable difference aboard our boats, in comparison to yester year, is that now we have a genset and solar panel at our avail.



I don't want anyone to get me wrong... If several thousand$$$ are spent to install the most advanced battery package on a boat - then living aboard can be made to seem DC powered enough to resemble the nearly unlimited electric comforts of home. However, that's not my game plan for pleasure boating and for the relaxation offered by inexpensive, easy to deal with battery and charger systems.



Simple is as Simple Does!! :thumb: :dance: :speed boat:
Just to be clear, I have a bank of FLA eight golf car batteries that give me all the juice I need. I am not a fan of lithium - expensive and long-lasting with a payback period such that I will long be dead before reaching break-even and that doesn't even consider the time value of money which, if considered, almost doubles the payback period. My present 5yo bank tests to 97% of original capacity. They will last at least four more years whereupon I can replace them with the Trojan brand for about $1,300. Last I knew the electrons coming out of FLA batteries are the same as those from lithium.
 
The group 24 batteries are somewhat inexpensive for AGM type. Just plan on replacing it every 3-4 years and you will be in good shape.


Why? Properly maintained an on a float charge they can last 8 years. I use 2 to start the main. I will replace them shortly but they start the main promptly. I have another for the Genny and it’s on its own Prosport charger and is 10 years old.

Jim
 
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