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Replacement Batteries

BOARF16

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2018 212X
This last summer the batteries stopped holding a charge and stated causing some issues with the motor. The boat sits in the water all summer with sometimes 2-4 weeks without use. I was hoping to replace the batteries with some deep cell AGM batteries that had a little more capacity, but go figure you can’t squeeze 2 of anything bigger than the 27 in the battery tray. When I spoke to someone a the boat shop, they said they didn’t recommend AGM batteries because they get too hot.

Anyone have any issues with AGM batteries overheating in the tray?
Any one find a combo of various groups that still fit into the battery tray?
Than
 

212s

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Never heard of AGM getting too hot, unless doing something crazy like charging at full C. That wouldn't happen in your boat as the charging system has a max output, or if you're using regular sized on-board chargers.

How about a regular start battery as they should last for years if taken care of properly - they work just like a car battery and no need for deep cycle unless you're combing. And then an AGM or LiFePo4 lithium battery for the house?

If total capacity is your goal, then add a third battery.
 

84rzv500r

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I just switched to a Group 24 size LiFePO4 60 Ah start battery and a pair of 100Ah Group 29 size house batteries... we'll se how it goes... to start with they are 200Lbs lighter than the Deepcycles I was running before...

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FSH 210 Sport

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2018 212X
This last summer the batteries stopped holding a charge and stated causing some issues with the motor. The boat sits in the water all summer with sometimes 2-4 weeks without use. I was hoping to replace the batteries with some deep cell AGM batteries that had a little more capacity, but go figure you can’t squeeze 2 of anything bigger than the 27 in the battery tray. When I spoke to someone a the boat shop, they said they didn’t recommend AGM batteries because they get too hot.

Anyone have any issues with AGM batteries overheating in the tray?
Any one find a combo of various groups that still fit into the battery tray?
Than
So, do you have 120 vac power at your slip? On board chargers?

What group size are the OEM batteries? Are these batteries in your boat the ones that came with it?

If you are not keeping those batteries on a charger while it’s sitting for a month at a time the engines are not going to charge the batteries back up properly and are sulphating. Your best bet for batteries that will tolerate sitting for a month a time with no charger and no ill effects are LiFePO4 batteries.

Never heard of AGM batteries getting hot…
 

BOARF16

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So, do you have 120 vac power at your slip? On board chargers?

What group size are the OEM batteries? Are these batteries in your boat the ones that came with it?

If you are not keeping those batteries on a charger while it’s sitting for a month at a time the engines are not going to charge the batteries back up properly and are sulphating. Your best bet for batteries that will tolerate sitting for a month a time with no charger and no ill effects are LiFePO4 batteries.

Never heard of AGM batteries getting hot…
The ones that came with the boat at Group 27 Interstate batteries. I do not have a 120V plug in, but I am going to hook them up to some solar battery tenders. I also haven't heard anything about AGM batteries getting hot, but figured I would ask others with similar boats and similar battery location configs. Maybe they guy who said AGMs get hot are only in his boat which I think is more on the Nautique boats.

Thanks for the help!
 

Inthrustwetrust

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The ones that came with the boat at Group 27 Interstate batteries. I do not have a 120V plug in, but I am going to hook them up to some solar battery tenders. I also haven't heard anything about AGM batteries getting hot, but figured I would ask others with similar boats and similar battery location configs. Maybe they guy who said AGMs get hot are only in his boat which I think is more on the Nautique boats.

Thanks for the help!
I’m running the stock start battery. Put in a 200ah AGM battery for the upgraded sound system. I haven’t noticed any heat. You can get a bigger battery tray on Amazon for $10-$20.
 

marcham

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I just switched to a Group 24 size LiFePO4 60 Ah start battery and a pair of 100Ah Group 29 size house batteries... we'll se how it goes... to start with they are 200Lbs lighter than the Deepcycles I was running before...

View attachment 172607View attachment 172610
I'm curious about this. On sailboats, lifepo4 are used as house batteries, with a dc-dc charger to recharge them from the flooded start battery / alternator.

How does your system account for the different charge properties of a lifepo4 compared to a flooded battery for which the stator is designed? What are the temp and voltage parameters of the BMS? If the BMS disconnects the battery, can it be re enabled without an external charger?

Any issues with the BMS discharge current protection affecting engine start?
 
Last edited:

FSH 210 Sport

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The ones that came with the boat at Group 27 Interstate batteries. I do not have a 120V plug in, but I am going to hook them up to some solar battery tenders. I also haven't heard anything about AGM batteries getting hot, but figured I would ask others with similar boats and similar battery location configs. Maybe they guy who said AGMs get hot are only in his boat which I think is more on the Nautique boats.

Thanks for the help!
The solar chargers will help, but they do not produce enough amps to properly charge lead acid batteries. For example, a 40 watt panel is only going to produce 2.85 amps maximum, you need a minimum of 10 amps to properly charge a lead acid batter. Again, the solar chargers will help, but ultimately the plates will sulphate and the electrolyte will stratify without the proper amount of amperage to clean the plates and mix the electrolyte.
 
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