On Board Charger Below Zero

[wllye]

Just wondering if you keep your on board charger plugged in during cold snaps below zero if it helps the batteries in anyway. I know i should take them out. Just wondering if it helps them charging

[Minnesota Tiller]

Just wondering if you keep your on board charger plugged in during cold snaps below zero if it helps the batteries in anyway. I know i should take them out. Just wondering if it helps them charging

It won't hurt your batteries at all to leave them out in your boat. As long as there is no draw they are fine. Make sure your batteries ground is unhooked and you will be fine. Batteries only freeze when there is a draw that makes the charge bad or "dead" then they will freeze like water does in a plastic container. The sides will buge out and the cores go bad. Very dangerous to try and charge or jump. If you do unhook you charger just make sure they are charged up and like I said above and as important unhook your ground. Leaving your on board charge is fine and probably the best scenario. I just talked to a Battery Factory Rep a couple of weeks ago he said the best thing for a battery is to charge it put in a plastic container and put in the freezer when not in use for long times. Not something I would do with a bunch of marine batteries but this guy has been in the business for over 30 years.

Hope this helps.
Mike M

[Dipstick]

Minus 31 C outside for the whole week in Winnipeg. Windchill at -45. Is this the same as putting them in a chest freezer???? LOL

I take my batteries out of the boat and store them in the garage (in the battery cases). Boat is in inside storage at another location. Once every 3-4 weeks I put a charger on them and take them up to full charge. I have also, in the past, kept them on an automatic "trickle charger" for the winter. Hasn't been a problem.

If I had an on-board charger, I would leave them hooked up and just plug in the charger every so often.

[wllye]

thanks guys for the input. Pretty chilly here in Montana

[Minnesota Tiller]

thanks guys for the input. Pretty chilly here in Montana
Over a long storage time leaving your batteries hooked up will ruin the life of them. Not so much on life line but how long they will hold a charge. Unhook them and leave your onboard charger plugged in all the time. It is made to give them a maintenace charge.

[steve l]

I leave my batteries in the boat, all hooked up and leave the on-board charger running. This will be the third set of batteries in over 10 years always "stored" this way and so far so good. The rep at Exide Batteries told to charge/maintain batteries this way over ten years ago so I guess he knows his business.

[JiMinneye]

I keep my 3 batteries plugged in to my on board charger throughout the year. This will be the 3rd winter leaving them plugged in and in the boat. Before I had the on board charger I would take them out of the boat fully charged and put them in the basement for the winter and charge them once a month, with the charger there is no need to do that anymore. Batteries are still in great shape and they are all 8 years old.
Jim

[rebs]

I leave mine in the boat and the onboard charger pluged in, my boat is in my garage. I use my boat all winter as the river does not freeze

[Triton HWA]

I leave mine on the onboard charger year around that is what the charge and maintennace feature of the better chargers is for. I usually get 5-6 years out of the batteries. I always change the Trolling batteries as a set, never have one better than the others, I also run Dual batteries on the Main engine due to the Optimax starting difficulties on low voltage. Cycling the batteries i.e. letting them discharge and recharge is what wears them S0o i keep mine full charge year around and use the duty cycles on the water:grin:

[boat nut]

A fully charged battery freezes at about 90 below F. For most of the last 14 years (and two boats), I charged my batteries and left them in my unheated garage, and it gets cold in Saskatchewan. The reason I did this was because I tilted the boat/trailer up, thinking it would shed snow better, and I didn't want to have leakage or expose plates to air. Well it didn't so I now store my boat level in my back yard, and the batteries are in it, but disconnected. I replaced my cranking battery in my 99 Prosport in spring of 2007. Not bad. I have been using one of my two Trojans for 7 years now, and the other for 4. I just replaced the battery in my '99 F-150 last week; 9 and 1/2 years for that one. Batteries will last a long time if you do regular maintenance.

[Dipstick]

Don't forget to top up the electrolytes before putting them away. If charger is on continuously, check the levels half way through the winter.

Merry Christmas to all.

[Grampa_Joe]

I winterize a ton of boats, and yes batteries can freeze. Like someone said earlier, I check to see the fluid levels are just above the plates, charge them completely, then I load test the battery to see that it's in good shape. After that, I clean up both sets of terminals, run a cable tie through all of the ground ring terminals and tie them to the battery strap. I can't imagine leaving a charger plugged in all winter, I've witnessed too many of them fail for one thing, and some have even started on fire.. The other problem is that a deep cycle battery is made to be drawn down and then fully charged, not continually charged. I don't know why someone would need to remove a battery from a boat. There is a natural discharge that will occur in a battery even without anything hooked up to it, but it's so minimal it will not have an affect in the time period we store our boats for the winter.
When a battery is fully charged the acid is present in the electrolyte (water) and as it discharges the acid draws into the plates leaving... plain water. Charged batteries don't freeze, discharged batteries freeze. I'm amazed every spring at the people bringing me batteries shaped like footballs or that even have the end blown off of it from freezing that say "I didn't do anything, the battery is bad". They are right, they didn't do anything, but should have properly winterized their batteries.
I've never had a single customer who's boat I've winterized have a battery problem in the spring. Not one.

Joe Carlson