Battery storage during winter

Post your technical questions or solutions about your boat's electrical systems or electronics here.

Moderator: KenKrawford

Post Reply
JMorgan
Posts: 6
Joined: Tue Apr 18, 2006 4:17 pm
Location: Greenwich Bay, RI

Battery storage during winter

Post by JMorgan »

Last winter, when faced with the prospect of removing my two D4 batteries (at about 125 lbs. per battery), I decided to purchase a good trickle charger and leave them aboard during the winter. The charger worked great, and the batteries remained fully charged and came through unscathed.

However, for this winter the yard has ruled that charging without the owner present is prohibited (i.e., no overnight charging). So once again I'm pondering battery removal vs. leaving them aboard and charging with a solar panel system (which is permitted).

How do you folks store your batteries during the winter? Do you remove them, or do they remain aboard? If you leave them aboard, what sort of charging system (if any) do you use?
Last edited by JMorgan on Wed Sep 26, 2007 8:19 am, edited 1 time in total.
John Morgan
Nunki #379
Greenwich Bay, RI
R.B.
Posts: 222
Joined: Fri Jan 20, 2006 2:04 pm
Location: Ontario, Canada

Leave them

Post by R.B. »

Last winter I fully charged them, made sure each cell was topped up and removed the wires from the terminals. In the spring, I attached the wires and charged the batteries and all was fine.
Ralph

WOLFHELM
C350 #342
JMorgan
Posts: 6
Joined: Tue Apr 18, 2006 4:17 pm
Location: Greenwich Bay, RI

Post by JMorgan »

WOW! No charging all winter??!! And you're in Ontario, so you certainly see some cold weather!

I always thought that they would freeze if a full charge wasn't maintained... apparently that's not the case.

Thanks for the reply.
John Morgan
Nunki #379
Greenwich Bay, RI
R.B.
Posts: 222
Joined: Fri Jan 20, 2006 2:04 pm
Location: Ontario, Canada

important

Post by R.B. »

Yes, the key is to have a healthy battery. So long as it is topped up and fully charged, it will not freeze in the winter. However a dead battery will freeze.
Ralph

WOLFHELM
C350 #342
Bob MacWright
Posts: 15
Joined: Mon Aug 06, 2007 11:30 pm

I'm going solar

Post by Bob MacWright »

I replaced my 4D batteries after only two seasons (and two winters), because I wasn't getting half the amp hours they were rated. I think two winters without charging sulfated them up.

I replaced them with 4 220AH golf cart batteries (from Sam's club, great deal). I also added a separate starter battery with a Blue Sea combiner, which I HIGHLY recommend. I can now use both deep cycle banks, where I used to have to save one for starting.

But I don't want to have these batteries go sour over the winter, so I considered all the alternatives. I could go down and put the charger on them for an afternoon every month, IF I can find an open outlet in the storage yard. But instead, I decided to go solar.

I just got my 40W Kyocera panel (20" x 24", 10 lbs), rail mounting brackets, a Solarguard 6 charge controller, 35' of #10 round cable, and a Blue Sea cable clam to pass the cable into the boat. I'm planning on mounting the panel on the stern rail, probably after removing the bimini frame. I should be able to point the panel south from whatever direction the yard puts the boat (I'll leave the cable real long, just in case I have to mount it somewhere else in future years.)

Why did I pick the equipment I did? I did LOTS of research on the web, and learned a heck of a lot. Then I called e-Marine, which specializes in marine solar, and they told me just what I had learned - that you need a 40W panel to keep 440AH of batteries topped up over the winter. (
As for the starting battery, I plan to take that one home.) I bought the gear from them.

Total cost, about $450. It should last virtually forever, and pay for itself in not having to replace the batteries - and not losing battery capacity, either. As a side benefit, the Sunguard controller also de-sulfates batteries, so if there is any sulfation on my batteries by time I haul out, it should be gone by spring.
DuncanMcMillan
Posts: 49
Joined: Mon Mar 20, 2006 9:44 pm
Location: Nanaimo, BC

Re: Battery storage during winter

Post by DuncanMcMillan »

Our boat will remain in the water for the winter with cabin heated, shore power and battery charger on.
Outside temp could get down to about 32F. Engine will be winterized and not available to run.
In reading the thread and provided I check battery level and SG periodically I think we should be good. Batteries are new.

Any concerns or recommendations?
Duncan #248
Para Handy
wolfe10
Posts: 464
Joined: Mon Dec 11, 2006 2:58 pm
Location: League City, Texas

Re: Battery storage during winter

Post by wolfe10 »

Even good, fully charged batteries will self discharge over the winter.

Do you have shore power where the boat will be-- if so use that to charge them up/or leave it plugged in with smart charger on.

If not, consider either a solar panel or take over a small generator a couple of times to power either the built in charger or a good portable one.

Brett
Brett Wolfe
C350 #180
"Vindaloo"
League City, TX
DuncanMcMillan
Posts: 49
Joined: Mon Mar 20, 2006 9:44 pm
Location: Nanaimo, BC

Re: Battery storage during winter

Post by DuncanMcMillan »

Thanks Brett,

Shore power will be on all winter with smart charger.
Duncan #248
Para Handy
KenKrawford
Posts: 486
Joined: Wed Nov 02, 2005 8:54 pm
Location: Atlanta, GA

Re: Battery storage during winter

Post by KenKrawford »

I left my so called "smart charger" on last winter and was greeted with the tops of all the cells in all 4 golf cart batteries exposed and dry. This year my charger will be off.
Ken Krawford
Message Board Moderator
C350 # 351
Lake Lanier, GA
DuncanMcMillan
Posts: 49
Joined: Mon Mar 20, 2006 9:44 pm
Location: Nanaimo, BC

Re: Battery storage during winter

Post by DuncanMcMillan »

Good point Ken. Aside from Feb I should be on the boat once a week and able to check battery level and SG.
Duncan #248
Para Handy
R.B.
Posts: 222
Joined: Fri Jan 20, 2006 2:04 pm
Location: Ontario, Canada

Re: Battery storage during winter

Post by R.B. »

Just as an example, your mileage may vary, I replaced my 2004 dated batteries this past summer 2013. I topped up and fully charged in the fall (Oct), unplugged them and charged them again in April when I went to open the boat in the spring. I also maintained my batteries during the summer season, topping them up when necessary and trying not to let them get below a 50% charge while cruising. I used them as my start and house bank batteries.
Ralph

WOLFHELM
C350 #342
wolfe10
Posts: 464
Joined: Mon Dec 11, 2006 2:58 pm
Location: League City, Texas

Re: Battery storage during winter

Post by wolfe10 »

Ralph,

You are very fortunate that the batteries still had a charge after that many months. All batteries self discharge, even with no load on them.

Any idea what the voltage was in the spring?
Brett Wolfe
C350 #180
"Vindaloo"
League City, TX
R.B.
Posts: 222
Joined: Fri Jan 20, 2006 2:04 pm
Location: Ontario, Canada

Re: Battery storage during winter

Post by R.B. »

HI Brett,

I don't remember the voltage, but the battery meter was usually around 70-75% for both. I installed a Victron Battery monitor this year with the new batteries (I replaced the 4Ds with 6V Golf cart batteries). So I should have a more accurate state of battery in the spring.

-Ralph
Ralph

WOLFHELM
C350 #342
wolfe10
Posts: 464
Joined: Mon Dec 11, 2006 2:58 pm
Location: League City, Texas

Re: Battery storage during winter

Post by wolfe10 »

Ralph,

Sure wouldn't hurt them (actually it would lower their freeze point and help with longevity) to go over a time or two with a portable generator to either power your on-board charger or a good high-amp portable battery charger.

Brett
Brett Wolfe
C350 #180
"Vindaloo"
League City, TX
Post Reply