For the guys that keep their boat outside or in a carport through winter...

[NY29T]

Just built an enclosed carport for my boat. Do you guys take all the batteries out for the winter? And I’m talking the north east area where it gets down to -5 sometimes. Not sure if some guys just hook up a trickle charger and leave em.

also anyone try mint extract to keep the mice out. Trapping as many as I can right now .thanks guys

[Grizzly]

I used to keep mine outside with no carport here in NJ with just a cover on it. I have on-board chargers and would just leave them plugged in and never had an issue. Make sure you tilt the motor all the way down to drain all the water after every use. I just read using Irish Spring soap will help keep the mice away, they don't like the smell.

[n2ratfishin]

Disconnect the speedometer if it’s a pitot type.

[ChampioNman]

And water pressure gauge hose.

[Dave A]

Disconnect the speedometer if it’s a pitot type.

And water pressure gauge, I lost 2 before I had a t put in the line so I could drain it.

[Dave A]

Sorry Champ, you beat me to it.

[Aruss1984]

100% take your batteries out. I'm in southern Ontario mind you, but I wouldnt take the chance of ruining my batteries by leaving them on-board in a car port over the winter. If you can even put them in a basement off the concrete floor connected to a trickle charger you're better off. I've ruined batteries even leaving them in my insulated garage. I wouldnt take the chance of leaving them outside in a car port. Just my 2 cents.

[paulrodbender]

I have always taken the batteries out and keep them somewhere warm and where I can throw a charger on them a couple of times during the off season. I have never liked to charge batteries with the rear compartment lid completely closed and have never liked to keep the batteries hooked up over the winter.

[Jaydbee]

I live in Jersey and kept my boats outside (20+ years) all that time. Wish I had a garage. I keep the batteries in the boat on the charger. I keep unplugged except for a day or 2 each month so charger can get the batteries into maintenance mode. Seems to work for me.

[v_fourmax]

If you can even put them in a basement off the concrete floor

Needing to store batteries off the concrete floor ended decades ago and with modern batteries it is totally a myth and not necessary although that rumor fails to die.

Leaving a car battery on a concrete floor won't do anything abnormal to affect the charge.
The belief stems from an outdated set of circumstances that no longer exist. Once upon a time, battery casings were made from more porous materials - tarred wood, rubber, etc. - which were susceptible to degrading after exposure to the moisture coming from unsealed concrete. As the casing degraded, battery acid could leak out and water could enter the battery, causing the battery capacity to drop.
With modern, plastic-encased batteries, the moisture-related degradation isn't really an issue on any meaningful time scales.
The reality is that a concrete floor is actually the best place to store a battery because the floor is normally cooler and batteries discharge at a slower rate when they are cool!

[Aruss1984]

thanks for clearing that up!

Needing to store batteries off the concrete floor ended decades ago and with modern batteries it is totally a myth and not necessary although that rumor fails to die.

Leaving a car battery on a concrete floor won't do anything abnormal to affect the charge.
The belief stems from an outdated set of circumstances that no longer exist. Once upon a time, battery casings were made from more porous materials - tarred wood, rubber, etc. - which were susceptible to degrading after exposure to the moisture coming from unsealed concrete. As the casing degraded, battery acid could leak out and water could enter the battery, causing the battery capacity to drop.
With modern, plastic-encased batteries, the moisture-related degradation isn't really an issue on any meaningful time scales.
The reality is that a concrete floor is actually the best place to store a battery because the floor is normally cooler and batteries discharge at a slower rate when they are cool!

[NY29T]

Any other thoughts

[depdog60]

I don't have any personal experience with mice repellents but a web search says that peppermint oil is best. In fact since we have it, I'm going to try it myself.
I've always stored my boat in a pole barn covered with the batteries in, onboard charger plugged in. I haven't had any issues.
I do take my tackle out though.

[Meleagris1]

Charged batteries will not freeze, you can leave them in the boat. I would make sure you drain all pumps, bilge and livewell pumps and unplug water pressure gauge line.

[Joe4d]

well anything can freeze.. A little google foo says, a fully charged battery will freeze at -76 degrees.. while a discharged on can freeze at 32... So as long as its full charged, ur good. Problem is it drops a few tenths of a volt and the freeze point changes quick. Couple years ago my tractor battery (marine cranking) froze solid.. Jumped it ran it to plow driveway,,,then put it on a trickle charger.. Surprisingly the battery was fine and lasted another year, although I replaced it before the next winter just because.

Oh and to add to the above, even after draining, I would add some RV antifreeze to the bilge, can ddilute any small amounts of water and keep it from freezing and cracking something like a bilge pump.

[Meleagris1]

This chart has some good info from one of the best battery makers out there. They say -92, but either way you are pretty safe in North American with a full charge. If it’s so cold you need to bring your charged boat batteries in you should bring your car battery in also.

https://www.trojanbattery.com/pdf/WP_DeepCycleBatteryStorage_0512.pdf

[DrewFlu33]

Charged batteries will not freeze, you can leave them in the boat. I would make sure you drain all pumps, bilge and livewell pumps and unplug water pressure gauge line.

This is the right answer!

Cold batteries store better than warm ones, or maybe put a better way, batteries store better in the cold than in the warm. This is because they lose their charge EXTREMELY slowly when it's cold. I thought this was nuts when the guy who stores my boat suggested and it went against everything I thought I knew until I started researching. See this chart from the Battery University:



Notice that even at 32 degrees (and the average temps are a lot colder than that over the winter where a lot of us store boats) it would take more than 18 months for a battery to discharge down to 75%. And based on this, average temps would have to be above 68 degrees for a 6 month storage before the charge would drop below a point to where it damages a battery.

As such, I always unhook my batteries, make sure they're topped off, and store them in my boat *unheated* over the winter. Unhooking is huge, because anything hooked up could drain power. As long as they're fully charged and not hooked up to anything, they'll maintain their charge all winter. I actually checked my batteries' voltage before and after storage this past winter, and it was an unusually long one here in the Twin Cities. When I put the boat into storage on November 4th, I had 12.91 volts + or - 0.01 on each of my 4 batteries. When I got it out of storage on May 5th - after a couple thaws during the winter and a couple weeks of warm temps leading up to that May 5th date - each of the batteries was sitting around 12.81 volts, again + or - a hundredth or two.

The way I see it, there's a much bigger risk of something going wrong with an onboard charger over the winter than there is with something happening to charged batteries that aren't hooked up to anything. Even if that's just the onboard charger dying, it will act as a parasitic draw for the rest of the winter as it sits dead. That's not even mentioning all the hassle of storing batteries somewhere or fiddling with them over the winter.

[illinifish]

Run some RV anti freeze through your pumps. The control switch can retain a small amount of water and crack when it freezes.
I have never been successful keeping mice out when I stored mine in the winter in a barn I have tried every method and combinations of. I just leave mine in the garage now and my truck sits out.

[191 champ]

I put the boat into storage on November 4th, I had 12.91 volts + or - 0.01 on each of my 4 batteries. When I got it out of storage on May 5th.

I have often wondered why or how humans inhabited such a place. No offense.

[twitch]

I've stored my boat outside for over 25 years and never taken a battery out charge them up and then once or twice I put a charger on them and there fine,it gets real cold here in the northeast and plenty of snow never a problem I double cover her and use a tarp on top of that .