Winter battery storage

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flatheadsteve

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Location
Berkeley springs WV
LOCATION
Berkeley springs wv
It's getting close to the point where the boat won't be getting used as much soon. December-Feb it rarely if ever sees use. I have 4 agm batteries and I'm debating on just leaving them connected to the onboarder chargers in the boat all winter vs bringing them Inside and putting them on a charger all winter. The boat stays under cover in one of those tent type garages. The 3 inside the center console are a bear to get in and out and if we get a warm spell mid winter I don't want to be wrestling batteries for hrs when I could be fishing. Anybody here leave batteries in the cold all winter? My boats in the past I always brought them in but it was an easy task as the batteries were easy to access.
 
Not too cold and not too hot with minimal temperature change

Remove at least one connection

clean the top of the battery well so as to leave no liquid or crud

I prefer a low amperage trickle charger.

what is an agm?

I am only discussing lead acid battery storage
 
Not too cold and not too hot with minimal temperature change

Remove at least one connection

clean the top of the battery well so as to leave no liquid or crud

I prefer a low amperage trickle charger.

what is an agm?

I am only discussing lead acid battery storage
Absorbent Glass Matt
I have noco and minnkota chargers. Both are "smart" chargers so they will trickle or condition the battery as needed.
 
I use to remove them. For the last 5-6 years have left them in. I fully charge when I put them to sleep, and charge again mid-winter, and again in spring wake-up. I haven't seen any longevity differences All are LA batteries. I don't like leaving chargers on long term. Voltage spikes/brown outs/lightning etc,, is the main reason.
 
I use to remove them. For the last 5-6 years have left them in. I fully charge when I put them to sleep, and charge again mid-winter, and again in spring wake-up. I haven't seen any longevity differences All are LA batteries. I don't like leaving chargers on long term. Voltage spikes/brown outs/lightning etc,, is the main reason.
I think I may go this route. I'm thinking once a month connect the chargers to keep them charged up and they should be fine.
 
Absorbent Glass Matt
I have noco and minnkota chargers. Both are "smart" chargers so they will trickle or condition the battery as needed.
If your chargers have the battery maintenence feature, just leave them connected, best for the battery !! Cold is only harmfull if battery has a chance of dropping to a low charge. Maintenence chargers do add life to a battery !!
 
A friend just went through this, expressly for frigid Northern New England Winters, and while the chargers are capable of low temps there are cautions about the battery chemistry itself at low temps to freezing or below. He even called the 'Genius' battery charger maker and they said, "Yes, the charger will be fine. but maybe not the batteries."

Also, due to the risk of electrical issues, I sure wouldn't advise it as I know a guy that lost his boat, garage and half his house to a fire - caused by the battery charger fritzing out. I also don't leaving any battery on a trickle charger and have observed 'cooked' batteries, but again I'm in a locale where it could be to freezing or below for days on end.

If leaving them on board, remember ... batteries have to outgas various gases to charge, that is hydrogen and constituent gases thereof ... which are heavier than air and will collect in the boat, are highly combustible, will burn in presence of oxygen explosively, and will ignite with a slight source of heat. Make darn sure the compartment and boat cover are WELL ventilated!
 
A friend just went through this, expressly for frigid Northern New England Winters, and while the chargers are capable of low temps there are cautions about the battery chemistry itself at low temps to freezing or below. He even called the 'Genius' battery charger maker and they said, "Yes, the charger will be fine. but maybe not the batteries."

Also, due to the risk of electrical issues, I sure wouldn't advise it as I know a guy that lost his boat, garage and half his house to a fire - caused by the battery charger fritzing out. I also don't leaving any battery on a trickle charger and have observed 'cooked' batteries, but again I'm in a locale where it could be to freezing or below for days on end.

If leaving them on board, remember ... batteries have to outgas various gases to charge, that is hydrogen and constituent gases thereof ... which are heavier than air and will collect in the boat, are highly combustible, will burn in presence of oxygen explosively, and will ignite with a slight source of heat. Make darn sure the compartment and boat cover are WELL ventilated!
And the Gov't is trying to sell us on electric..battery powered vehicles !!
 
I'd hate to have to pull batteries at my age and haul them inside for a trickle. I know guys that leave their boats on a lift all winter and run a solar trickle charger to them. Never seen nor heard of a problem. However, if the battery manufacture doesn't recommend leaving them out all winter, maybe you'd better not.
 
I use to remove them. For the last 5-6 years have left them in. I fully charge when I put them to sleep, and charge again mid-winter, and again in spring wake-up. I haven't seen any longevity differences All are LA batteries. I don't like leaving chargers on long term. Voltage spikes/brown outs/lightning etc,, is the main reason.

Ditto. Those chargers aren't cheap and I think it's a mistake to leave them plugged in all the time.

I'd isolate the batteries (disconnect your electronics or cut your main power switch if you have one), leaving only the charger connected and plug it in periodically.

Self discharge drops to almost nothing in cold weather, and a charged battery won't freeze so there's really no reason to take them out.
 
I don't use my built in chargers, but I do have a number of the " battery tender" maintence chargers. I add one to every battery on my toys and leave them in all winter. For only pennies in electricity my batteries stay charged and do not have sulfation issues. Also longer life expectency!!
 
I was just lending a moments thought to this, I have a custom/classic car that I don't drive during winter. I have a tender hooked up from Nov -March or April. I do start her once a month or so during winter to lube the gaskets and shift the transmission FNR. But other then that she's in the garage but it's not heated.
 
A friend just went through this, expressly for frigid Northern New England Winters, and while the chargers are capable of low temps there are cautions about the battery chemistry itself at low temps to freezing or below. He even called the 'Genius' battery charger maker and they said, "Yes, the charger will be fine. but maybe not the batteries."

Also, due to the risk of electrical issues, I sure wouldn't advise it as I know a guy that lost his boat, garage and half his house to a fire - caused by the battery charger fritzing out. I also don't leaving any battery on a trickle charger and have observed 'cooked' batteries, but again I'm in a locale where it could be to freezing or below for days on end.

If leaving them on board, remember ... batteries have to outgas various gases to charge, that is hydrogen and constituent gases thereof ... which are heavier than air and will collect in the boat, are highly combustible, will burn in presence of oxygen explosively, and will ignite with a slight source of heat. Make darn sure the compartment and boat cover are WELL ventilated!
Hydrogen is lighter than air. Remember the Zepplin? :) All you need to do is open the compartment holding batteries and chargers and any hydrogen will float away.

I wouldn’t recommend keeping LifePO batteries on a charger. They like to be stored about 1/2 discharged.

As far as lead acid, AGM, etc. they will self discharge faster when it cold. Better than leaving the onboard charger on trickle all winter, put them on a timer so the charger runs just a few hours per week. Deep cycle batteries don’t like to be trickle charged for long periods.
 
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I was just lending a moments thought to this, I have a custom/classic car that I don't drive during winter. I have a tender hooked up from Nov -March or April. I do start her once a month or so during winter to lube the gaskets and shift the transmission FNR. But other then that she's in the garage but it's not heated.
When I had my motorhome, I did that same thing...worked well !!
 
Hydrogen is lighter than air. Remember the Zepplin?. All you need to do is open the compartment holding batteries and chargers and any hydrogen will float away.

I wouldn’t recommend keeping LifePO batteries on a charger. They like to be stored about 1/2 discharged.

As far as lead acid, AGM, etc. they will self discharge faster when it cold. Better than leaving the onboard charger on trickle all winter, put them on a timer so the charger runs just a few hours per week. Deep cycle batteries don’t like to be trickle charged for long periods.
According to my battery specs, they do like to be left on a maintainer over long storage, as long as the battery is fully charged to start with. Trickle charging a battery with a low charge to start is bad for them...
 
According to my battery specs, they do like to be left on a maintainer over long storage, as long as the battery is fully charged to start with. Trickle charging a battery with a low charge to start is bad for them...

Well, it didn’t work so well for me last winter. I’m pretty sure that I killed a pair of 110 Ah AGMs leaving them on the onboard charger’s trickle mode for six months.

When you consider commercial applications like a computer server UPS, they will do a maintenance charge every 30 days or so.
 
OK, this had me scratching my head. I get curious and start reading stuff. What I read is that the gas off put from overcharging a battery is hydrogen sulfide. Unlike hydrogen gas, hydrogen sulfide is heavier than air. If you smell rotten eggs, then you might have an explosive mixture. Seems like there is always something waiting around they corner to bite us if we aren't careful.
 
I didn’t question that it was hydrogen sulfide rather than hydrogen. It makes sense that hydrogen sulfide is heavier.

I don’t think most modern high quality chargers with bulk, absorption and float or trickle modes necessary overcharge batteries. It’s just that long term trickle charging isn’t ideal for AGM batteries.
 
Hooked up or Not > When charging, I use "solar' have a couple panels on my shed roof running wire's inside, they sit up on a shelf around 4 inches away from each other, Never had an issue with them and lasted, heck some lasted longer than life expectancy. Believe it or not I still have a backup battery I use when trolling with my pelican I use one for lights and one fort trollin & I have had this battery well going on 15 yrs. Solar charging panels their cheap buy em from EBAY> heck it's handy enough & small enough to bring along and throw on the battery while I am resting having lunch or dinner or just taking a break , before continuing fishing . another good thing about the solar panel is anything that is usb can be charged has pin multi port system if you wish a handy item!
 
Hydrogen is lighter than air. Remember the Zepplin? :)
Yeah, yeah, i know all about Led Zepplie, LOL ... but you're forgetting about the OTHER hydrogen mix gases generated ...

Hydrogen sulfide being just one, it is heavier than air, highly toxic, and extremely flammable.

Whatever, people are free to do what they want.
 

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