This is my first winter storage for my 2002 Beneteau 411 that I purchased at the beginning of this year. I would like to leave the batteries on the boat for the winter with periodically charging them for a few hours a month. Does anyone have any information or experience with storing the batteries a hard?
Storing my batteries for the winter
- Thread starter natep
- Start date
I've done the same thing for many years - batteries only lose a couple of percent/month in cold storage and that's fine. I added a small solar panel last year to keep the batteries topped up and they were fine.
BTW, my marina charges $100/battery to store for the winter - I asked what they did; they charge the battery fully and then leave them on a pallet, outside under a tarp.....
BTW, my marina charges $100/battery to store for the winter - I asked what they did; they charge the battery fully and then leave them on a pallet, outside under a tarp.....
I have always left my batteries in the boat, no problem. I simply fully charge and disconnect both positive and negative (really don’t think disconnecting negative is necessary). I have no access to power for a trickle charger, so they go all winter without. The boat is in northern Michigan so consecutive subzero winter days are no uncommon.
The boat remained on the hard from September 2015 until May 2017 due to extenuating circumstances. When we recommissioned and launched without recharging those batteries they still indicated 12.5 volts, and the engine started immediately. The marina techs told me that they have never had a problem restarting my boat in the spring.
The boat remained on the hard from September 2015 until May 2017 due to extenuating circumstances. When we recommissioned and launched without recharging those batteries they still indicated 12.5 volts, and the engine started immediately. The marina techs told me that they have never had a problem restarting my boat in the spring.
I too disconnect my fully charged batteries. My first winter I left them connected, and by the time Spring came around they were dead as a dodo. That was an expensive mistake. Ever since I disconnect them completely, but leave them in place on the boat. I don't bother hooking them up to a charger at all during the 5 months away, but I DO go up a few times (2+ hour drive) to check the batteries. I just went up the weekend before last and all the batteries still show more than 12.6, that's after the boat was hauled out on Oct. 6. I'll go up again in a month or two, and if history is any indicator the battery levels may drop from 12.87 to 12.83-ish.
You can leave them onboard if the yard has nearby power. Either use your standard 30 shore power cable, or buy a standard plug adaptor for it that allows you to plug it into a 15amp receptacle. Then you can use your vessel battery charger.
Hey guys, thanks. I am going to fully charge the batteries and then disconnected them!! Thank you all very much.
Nate
Nate
I pulled one battery from boat number one. My truck battery died in the home Depot parking lot while working on my trailer lights. I pulled two batteries from boat number 2. Then I picked up two more slightly used batteries. Now I have six batteries laying around and just found out today I could've left them in the boat 
I was afraid I was the only one that left the cables on over the winter.
My cables to the switches are short and there is nothing attached until after the switch. I try to eliminate things to do in the fall and spring.
It depends on your set-up. You can have parasitic loads on bilge pump sensor, solar panel controller, potentially radio. If you disconnect the batteries, there is no parasitic load, for sure.
If you are sure that there is nothing between the battery and the switch, your batteries will be fine when you turn that switch off.
My boat has blue sky solar panel controller which gets and turns on with solar power not battery.It's not good to power anything before switches and does not meet abyc.
I leave switches on for bilge pump and sensor
I have done it both ways, but feel more comfortable that I can leave the boat and batts alone all winter and not drain the batteries.
I can’t charge using the charger when hauled out, so if I want to charge, I have to open the battery compartment, remove the box covers and hook up to each battery...
Greg
Our Beneteau came from the factory with about 30 mA of parasitic loads when the switches are off. The bilge pump, coutesy light radio receiver, stereo memory circuit, and high water alarm are all individually fused before the switches. If I just turn the switches those will cause over 20aH per month of drain. Leaving the batteries sitting at that reduced SOC for the winter wouldn't be good for them.
DavidSailor26
We live in Michigan and have left our batteries on our boat for the past 20 years with no issues. We took out the first year and it is not a fun process. We disconnect the cables from the terminals and the batteries are fine in the spring. As someone mentioned to me, "you would not think of taking your batteries out of your car in the dead of winter even if your car sat outside for a month...."
No, but if your boat sits outside for 4 months you might want to check SOC and put a maintenance charge on them as needed. At minimum expect 5% discharge every month, even if they are disconnected. More if the weather is warm.
https://www.trojanbattery.com/tech-support/battery-maintenance/
Completely agree that there's no need to carry them away, especially if you have a way to give them one or two mid-winter charges. I'm not suggesting to remove them, just to disconnect them so they're not vulnerable to parasitic loads.