Keeping batteries fresh in winter months

[zippy83]

Hi all,

What is the best way to keep batteries fresh in the off season. Like many of you I have two deep cycle batteries on my boat. The boat is garaged and I have two chargers with maintainer built in that I keep on throughout the winter. Is that enough or should I look for some better solution?

Thanks
Zipp

 

[alldodge]

IMO Keep a 3-stage maintainer attached to the battery, disconnected or connected to the boat

 

[robert graham]

I remove my battery from boat and set it in my garage, put it on a 2 amp charge every few weeks to keep it topped off....I've always heard a battery maintained with a full charge will last longer and be more dependable with long life....sorta makes sense!...

 

[gm280]

zippy, back in my R/C airplane flying days they sold a little circuit that you would connect the battery charger(s) to and plug into a standard outlet. It would allow the charger to turn on for a few seconds and then turn off for a few more seconds. And you could leave the batteries connected forever without worry of overcharging and it kept the batteries fully charger until you needed them again. That would work for your setup. But if you already have chargers with built in long maintenance capabilities, I see no problem letting them connected as well. JMHO!

 

[Scott Danforth]

I use a solargizer brand maintainer ( I have both solar and AC power supplies) The pulsing prevents battery plate sulfation

 

[bruceb58]

IMO Keep a 3-stage maintainer attached to the battery, disconnected or connected to the boat

++++1 That is what I do too

The more a battery is left discharged, the more it will sulfate. Even if the battery only discharges 20% over winter, that is detrimental to the battery.

 

[NYBo]

What you are doing is just fine. Disconnecting the batteries would be a good idea. This ensures there is no load on them, and forces you to look at the connections come Spring so you can make sure they are clean and tight.

 

[fhhuber]

Partly depends where you are...

Here... rarely below freezing even in winter. so keeping it on a maintainer in the boat is fine.

Someplace where it hits 40 below zero (F or C doesn't matter... that's about where they cross) I'd pull the battery and keep it someplace a little warmer... but still on a maintainer.

 

[bruceb58]

A fully charged battery doesn't freeze until -76 degrees.

 

[flyingscott]

Keep the charger plugged in and don't look at them again till you are ready to take the boat out again. You can double and triple the life of the battery by keeping it charged over long storage periods. Especially important if you have a FI or DFI as those computers always have a drain on the battery.

 

[bruceb58]

Especially important if you have a FI or DFI as those computers always have a drain on the battery.

Hopefully, most people have battery switches on their boats so there shouldn't be a drain but I do agree on keeping them fully charged.

 

[H20Rat]

Every one of my off-season batteries gets at least a couple weeks on the desulfator... Just make sure you have NOTHING else connected, especially not a smart charger. Desulfators work by storing a little bit of charge and then releasing a high voltage blast into the battery, hundreds of times per minute. That voltage blast can and will fry other electronics.

 

[Scott Danforth]

they have self energizing desulfators (pulsers). they are intended for stand-alone gensets that go thru a weekly self test (30 minute run). anything longer than 3 months and the battery will have discharged due to the small consumption of the pulser. However many maintain chargers also pulse.

 

[zippy83]

Thank you all for the responses. I live in Missouri so it's not crazy cold in the winter. Both batteries on the boat are disconnected and hooked up to a charger with a built in maintainer. Both batteries were purchased in Spring of last year. I guess I am not douing anything wrong here.

Thanks again
Zipp

 

[JoLin]

A fully charged battery doesn't freeze until -76 degrees.

The boat sits in my driveway all winter. Batteries stay aboard, disconnected and terminals cleaned. I use a portable smart charger to desulfate and fully charge them before the boat gets wrapped. Last Spring they still showed 12.4 volts or thereabout. I recharged them and was good to go.

My opinion is this... If the battery won't maintain its charge over the winter, it has a problem. I'd rather find that out before I splash than have one of them fail later when I'm away from the dock.

My .02

 

[bruceb58]

Last Spring they still showed 12.4 volts or thereabout. I recharged them and was good to go.

By the time they get to 12.4, they have discharged down to the 80% level. Why not keep them at 100% with a maintainer and load test them in the spring? You will have a lot less sulfation happening by doing that. On every boat that I own, I have a mounted 3 stage charger that is plugged in 24/7 when the boat is stored.

 

[Grub54891]

I simply charge them when laid up for the winter,unhook, and walk away. Come spring I hook them up, start the boat and have fun. If it won't start, they were on their way out anyway. Usually get a good 5-6 years out of them.

 

[JoLin]

By the time they get to 12.4, they have discharged down to the 80% level. Why not keep them at 100% with a maintainer and load test them in the spring? You will have a lot less sulfation happening by doing that. On every boat that I own, I have a mounted 3 stage charger that is plugged in 24/7 when the boat is stored.

You may be right, but IMO my smart charger will take care of any sulfation that occurs over the winter without any ill effect to the battery. Most years I leave the boat for several months while I'm snowbirding in FL. I don't trust maintainers or anything else plugged in and left unattended. When the time comes that the battery has a major discharge over the winter, or the desulfation fails, or the load test fails, it'll be time to replace it.

My .02