[stuart11]

Have a regular 12v battery, what do I need to do (if anything) to winterize.

I'm storing it in our basement, which does get cold in MA winters.

Have a small solar panel I used during the season to keep it topped off.

Thanks in advance for advice.

sw

 

[kwaltersmi]

Here's what I do:

- Check electrolyte levels and top off with distilled water if necessary.
- Make sure the batteries are fully charged
- Disconnect the batteries, clean/dry top of battery and connections

FYI - I keep mine onboard during winter storage.

 

[stuart11]

Thank you kwaltersmi!

 

[Donna_F]

We do the same as Kwalltersmi but we bring them home and attach to a charger in the garage. Over the winter we rotate which battery is attached. With larger boats and larger battery banks that becomes a pain if it's even possible, but for now we can easily remove the batteries.

 

[stuart11]

Thank you, DRFerron

 

[Barquito]

For years, I took mine out and charged in the basement. Last year, I left them onboard. We get pretty cold here in Wisconsin. They hardly lost any charge at all.

 

[mbianka]

I have two battery banks on board. The house bank is two group 27 Gels, The propulsion bank is four 8A4D batteries in series making it a 48 volt bank. They have been on board since they were installed seven years ago. They remain connected through the winter. Both have solar panels connected through Morningstar controllers keeping them topped up. The 48 volt bank also has a 48 volt wind turbine connected to the bank. For the most part the solar panels keep things topped up in both cases. But, I do check on the boat at least once a month (often more if the weather is nice) and power up the 120 volt battery chargers when on board. Not that is really needed. Seven years and both banks are still going strong.

 

[stuart11]

Good to know mbianka!

Thank you

 

[Gary M]

I leave mine on board but charge them about the first of the year. If am always concerned that if they get too run down, the acid concentration will be low enough that they might freeze and crack.

 

[Don L]

I fully charge them and even equalize for a few hours, disconnect them, and leave them on the boat. This spring when I hooked them back up they were still at 12.5V.

 

[Dfok]

Batteries need to be toughened up, not coddled. Bringing them indoors makes them lose electrons ( I'm Positive) which renders them fat and lazy, like your neighbor's pampered dog or an errant relative's stepson.
No amount of beating or cussing on a group 24, 27 or varieties such as 4's, 8's, 16's or the Orwellian mutant LiOns will revive a recalcitrant battery from a stupified state.
Many modern batteries seem to simply enjoy burning a light, starting a tractor or snow blower now and then. Most ( especially older) left to there own devices prefer to hibernate and like bears are best avoided while asleep in their accustomed battery lair.
Virgin, hopeful, new or especially stupid (and terribly, awfully old) batteries may be given a bit of juice now and then - solar, wind, diesel, gas or pedal power, the electron storage device cares not - a wink is as good as a nod to a blind horse or a lead enfeebled battery.
Our generally faithful power pod abides no season. Is there "ert" while our lead acid friend lies inert? - is it just us inert while our batteries wait for action?.
Hmmm?

 

[T37Chef]

Page 16 of linked reference http://www.trojanbattery.com/pdf/TRJN0109_UsersGuide.pdf

If I am storing the boat in the water as I often do during the winter months I just keep the battery charger on using shore power, next year I hope to have solar set up as I should be on a mooring. If storing the boat on land, keeping shore power on is often not allowed for insurance reasons or yard rules, so either solar or fully charged as reference in the link above.

Cheers

 

[stuart11]

Thank you Don0190

 

[Minnewaska]

How's a solar panel going to work in the basement?

Why not leave them aboard and use the solar panel there? If you do, it's always best to disconnect everything from the batts. Parasitic load can drain the battery, even when nothing is turned on.

A fully charged battery will not freeze and the cold weather slows any self discharge. Your solar should see to it that this is a non-issue anyway.

We leave all ours aboard and simply top up the charge about every 6 weeks.

 

[Maine Sail]

Winter Storage - Effect of Cold on Self Discharge

 

[hellosailor]

Simple and not altogether unreasonable solution would be to get a Deltran Battery Tender or similar gizmo, which plugs into the wall and keeps a small charge on your battery during "storage".

Wet lead batteries self-discharge all the time, and if they sit without any charging to compensate for that, they will take internal damager from sulphiting, with a permanent loss of capacity.

So, by all means question which gizmo works best or properly, but any one of them should beat nothing at all.

 

[Don L]

So, by all means question which gizmo works best or properly, but any one of them should beat nothing at all.

Why? Charging them up at the start of layup and disconnecting them (ie doing nothing) works fine and in the Spring the batteries are at 90+% SOC.

Doing nothing works pretty darn good.

 

[hellosailor]

"Why?"

Because you can't SEE the damage and the odds are you don't have access to the equipment to do any real meaningful SOC testing. The folks who do have that and use that, the battery makers, all have an interest in selling you new batteries as often as they can.

And yet, they ALL will say what I just said. Thirty days, and you've probably damaged the batteries. 90 days, and you've definitely damaged the batteries.

You think doing nothing works well enough? OK, do nothing. They'll be happy to sell you new batteries every three years instead of every six or eight years.

Not my opinion. Objective fact, repeated and confirmed by every business that's in the business of making batteries.

 

[Maine Sail]

"Why?"

Because you can't SEE the damage and the odds are you don't have access to the equipment to do any real meaningful SOC testing.

I do have the test equipment, about $5000.00 worth, I am also one of the only marine electrical systems techs offering physical capacity testing. I am one of the few who has ponied up for the equipment to do that.

I also work directly with battery manufacturers and am currently in the middle of some long term PSOC testing for one of them right now. This is a new AGM variant that looks very, very promising. I compile data, run testing and send the data off to the manufacturer.. This testing has been geared specifically at marine use and how to best develop a battery that can survive this type of abuse. This company understands not everyone will move to LiFePO4 or other chemistries so is working hard to build a sulfation resistant lead acid battery. This gives me excellent access to some of the best engineers in the business, and still, I leave my LA batteries on board all winter......

Yep, I leave my batteries on-board 100% disconnected but charged/equalized before disconnecting. I can do physical capacity tests to see exactly the impact it has. I have done this multiple times. (capacitance, pulsed load and carbon pile testing is a joke compared to a physical 20 hour capacity test) It has not lead to shorter life and in fact the batteries I service last a good long serviceable life nowhere close to 3 years..

Heck even my AGM reserve battery, that winters on-board, is not on a charge all winter and my boat is 4' from my house. I use one of the smartest chargers made yet I still won't leave it unattended because there is simply no need to do that in the winter... I simply won't do that to my battery when there is less than zero need to.....

And yet, they ALL will say what I just said. Thirty days, and you've probably damaged the batteries. 90 days, and you've definitely damaged the batteries.

And because you don't have the equipment you believe them, then connect to a charger and leave it there thinking it will do good. Remember these are the folks trying to sell you lead who are telling you to leave a battery on constant charge....

Most of these chargers are certified pieces of $hit and are far from anything even resembling smart. They do nothing to prevent stratification during winter storage and all they do is hold the voltage slightly above resting with mA level current that serves no real purpose in cold weather because there is little to no self discharge going on..

My now 8 year old Wal*Mart batteries have outlasted many sets of Trojan's left on charge but yet they were left on-board every winter not on charge. Can't be? Cold weather slows all the chemical process dramatically including sulfation and self discharge. This is chemistry 101..

You think doing nothing works well enough? OK, do nothing. They'll be happy to sell you new batteries every three years instead of every six or eight years.

I had a set of 12 year old GEL's on my bench two weeks ago for capacity testing. They have been on-board for 12 years and not charged in the off season... I have many customers well beyond 8 years with typical wet cells all stored on-board & disconnected. As long as the batteries are put away properly the only real effect you have is stratification but a constant float charger will not prevent that either. Oh the marketers will have you believe their charger is as smart as Einstein they do still do not prevent stratification.It is is pure hog wash that a constant float voltage prevents stratification. You need to roll the electrolyte to do that and this requires voltages above gassing... So now you have stratification WITH additional charge current. Think about it, I do, and this is one of many reasons I will not leave a battery in cold storage on constant float.....

I would personally rather see an owner hit them with 14.6V - 15.5V once or twice per winter, a good gassing voltage, than risk burning their boat down with a crappy "smart" charger. Most yards disallow any sort of charging during the winter for just this reason..

Not my opinion. Objective fact, repeated and confirmed by every business that's in the business of making batteries.

Your facts are simply opinion when it comes to winter storage.

 

[hellosailor]

Maine-
Gels are nothing like wet lead acid when it comes to long term and sulphating. You know that as well as I do.
And obvisouly, all chargers and maintainers aren't built to the same quality.

But what? Do you think the battery companies are all telling the same lie, that the batteries will sulfate and lose capacity? All lying because, what, they get paid back by the battery "tending" makers?

I don't doubt your equipment, your tests, or your veracity, but I also don't think the entire battery industry is engaged in some grand conspiracy to misinform the public about how batteries should be treated in storage. Not that it isn't possible, just that it is more likely there's some other reason that your observations don't match their statements.