Winter storage procedure for batteries. What do you do?

[Sandman251]

Sorry to say, but the Boating season is winding to an end here in Michigan. Wondering what everybody does with their batteries in cold climates. After reading almost everything there is to read on the topic, I think I've decided to top off my battery and just leave it in the boat all winter with the negative terminal disconnected. With no parasitic drain, there should be almost no voltage drop during the freezing winter months. I know many people pull the batteries and put them in the garage on a piece of plywood with a maintenance charger. It sounds like any benefit to this procedure is largely a wives tale. I'm all ears though.

 

[drjack]

It really depends on the age of the battery. As it ages, the plates will be sulphated and unable to hold a sufficient charge for the duration.
When a battery losses it's charge during the winter, that's when a battery is capable of freezing. A sign of freezing is a notable bulging of the battery case.
I owned a sailboat equipped with 3 deep cell "house" batteries for over night anchorages. I always left them on board for the winter after one good final charge, and this was the Georgian Bay region. It gets nasty cold up there.
I noticed one year that 2 of them bulged and unable to charge but they were 7+ years old by then.
One fellow boater had a battery that split over the winter. That turned out to be a disastrous problem as battery acid flooded the bilge, and ate the bilge pump, plus several fittings. It took hours of cleanup and a costly repair bill of the damage.
The plywood base is a myth. Proven several times that there's no benefit.

 

[ORION '95 Speedster]

Run an extension cord out to the boat and put the batteries on a floating trickle charger. If its more convenient, you can hook them up to a solar powered battery tender. That will keep the voltage up, prevent freezing, and give you the maximum battery life overall.

 

[Mask1]

Well I will give you my 2 cents ... I used to pull the battery and charge it and keep in my heated basement then charge again in the spring ...and I would get 4 or 5 years from my batteries.
My buddy worked at one of the 2 battery manufacturers in North America (there are only 2 main battery makers) he told me to do the following and have batteries that have lasted over 10 years now.
1 - end of season remove all draws from the battery posts and fully charge ...leave it in the cold ... do not take into the heat(inside the house). Believe it or not I am in Canada gets as cold as -40 and I leave the batteries outside.
#2- charge again in the spring before use and bingo your good to go that simple
There are lots of wives tails with batteries . Eg. Don't put on concrete ... don't let it get cold ... all BS .
The reasoning behind this is when a battery is in heat the cells are active and always killing themselves slowly. When you leave it in the cold the battery is almost dormant .. adding lots and lits of lifetime for seasonal sports ...therefore ... in Winnipeg anyways my battery is active only 6 months of the year now. And I have some that are going on 12-14 years now with this procedure. Very very important to remove any draws and charge 100% before winter and 100% charge again in spring.

Good Luck !!!!

 

[ORION '95 Speedster]

So your saying to charge before storage and charge after storage, but keep them cold rather than warm. Seems like putting them in the freezer might be a good idea then.

 

[Mask1]

Well if you're not in a cold environment then go ahead ... tried tested and true. I leave them all in an unheated garage all winter from Oct - may with only the one charge . Every person I have shared this with has had the same results . Look it up . Like night and day the activity in a battery from cold to hot.

 

[Mask1]

So your saying to charge before storage and charge after storage, but keep them cold rather than warm. Seems like putting them in the freezer might be a good idea then.

Believe it or not after you mentioned the freezer I know many people who store their AA and AAA batteries in the freezer for longer life ...lol

 

[mrlmd1]

Batteries do not like to be discharged, it shortens their life. While you may get away with what you are doing, the best practice is to keep them fully charged, like on a solar or other trickle charger when stored. It doesn't have to be anything fancy, even those little boxy 120V-12V adapters will do, anything to supply 1/4-1/2 Amp to keep the battery from discharging over time. And if you have a non-sealed lead acid battery, make sure the electrolyte level is topped off to the correct level (with CLEAN or distilled water, not acid).

 

[Seadoosam]

We leave ours in the basement (heated) and put it on a cheap Harbor Freight maintainer. I have heard not to store on concrete also