What to do with batteries over winter??

[Picks]

I'm seeking advice on what to do with the batteries. I have 2 120aH batteries on board which are supplied by a solar panel. My query is should i remove the batteries completely and take home to trickle charge, disconnect them but leave on the boat or leave as they are and let the winter sun keep them topped up? The boat is now on the hard so can't run alternator to charge.

Thank you.

 

[sailorman]

I'm seeking advice on what to do with the batteries. I have 2 120aH batteries on board which are supplied by a solar panel. My query is should i remove the batteries completely and take home to trickle charge, disconnect them but leave on the boat or leave as they are and let the winter sun keep them topped up? The boat is now on the hard so can't run alternator to charge.

Thank you.

leave them as they are the panels will keep them good

 

[Picks]

That was quick sailorman. Thanks for prompt reply. Thought ( and hoped ) that was the answer. One less thing to get in the car next week!!

 

[sailorman]

That was quick sailorman. Thanks for prompt reply. Thought ( and hoped ) that was the answer. One less thing to get in the car next week!!

we have a wind gen & the variable trickle charge they get, safer than battery chargers

 

[sarabande]

have you got a regulator in the system ? There's a faint chance the batteries may be fully charged, and then without a regulator, overcharged. And also a risk of fire...

I'd take them home, put them somewhere cool (not freezing) on a small raised platform, and charge them from time to time. They really don't like freezing conditions, and if the boat doesn't have background heating, a frozen batt is a damaged one.

 

[VicS]

have you got a regulator in the system ? There's a faint chance the batteries may be fully charged, and then without a regulator, overcharged. And also a risk of fire...

I'd take them home, put them somewhere cool (not freezing) on a small raised platform, and charge them from time to time. They really don't like freezing conditions, and if the boat doesn't have background heating, a frozen batt is a damaged one.

But it will have to get very cold to freeze the acid in a charged battery. It can freeze if discharged though. (Wikipedia gives the exact Fpt of battery acid .. Ive looked it up before)
People all over leave their car batteries outside in their cars.

But I do as you suggest. I bring my boat battery home and charge it now and then over the winter.

I find the solar panel is not effective during the winter ........ 'cos the boat is covered!

BTW it is often said that batteries should not be stored on a cold concrete floor.

 

[Jcorstorphine]

Perhaps cycle them.

But it will have to get very cold to freeze the acid in a charged battery. It can freeze if discharged though. (Wikipedia gives the exact Fpt of battery acid .. Ive looked it up before)
People all over leave their car batteries outside in their cars.

But I do as you suggest. I bring my boat battery home and charge it now and then over the winter.

I find the solar panel is not effective during the winter ........ 'cos the boat is covered!

BTW it is often said that batteries should not be stored on a cold concrete floor.

A lifetime ago, my father used to bring home the battery from the boat and connect a 24 watt headlamp bulb (it was a long time ago) to partially drain the batery down to about 10 / 11 ish volts and then recharge it with a trickle charger, leave for a month or so and then repeat a number of times. From memory that battery was still as good as new 10 years later when the boat was sold.

 

[sailorman]

A lifetime ago, my father used to bring home the battery from the boat and connect a 24 watt headlamp bulb (it was a long time ago) to partially drain the batery down to about 10 / 11 ish volts and then recharge it with a trickle charger, leave for a month or so and then repeat a number of times. From memory that battery was still as good as new 10 years later when the boat was sold.

my last set of batteries lasted 9 yrs o/b.
one was scrapped the others were then in service in a beach hut & probably still there some 14 yrs old

 

[Skylark]

I used to remove the batteries and take them home. Now I think it's pretty much a waste of time, certainly not worth the effort.

My boat sits in its cradle over winter. I live 120 miles from the boat so don't visit regularly while she's hibernating. When I do go, if I'm there for more than a few hours I'll plug in the 240v and charge the batteries. Probably no more than once or twice over the winter season.

Maybe I've been lucky but I haven't removed the batteries for several years. They are now 6-7 seasons old and if they fail tomorrow, they don't owe me anything. Perhaps the purists would argue differently but my advice would be "do nothing".

 

[ghostlymoron]

A lifetime ago, my father used to bring home the battery from the boat and connect a 24 watt headlamp bulb (it was a long time ago) to partially drain the batery down to about 10 / 11 ish volts and then recharge it with a trickle charger, leave for a month or so and then repeat a number of times. From memory that battery was still as good as new 10 years later when the boat was sold.

When I first had a boat I read that the best thing to do was COMPLETELY discharge them and then re-charge a few times during the winter. I did this using a car side light bulb and battery charger. In the spring, i re-installed the batteries and the were completely wrecked.
The next winter I left it (I decided I didn't need 2 leisure batteries - not at £100 each anyway) and left a Halfords automatic charger permanently connected. In the spring, the battery was again wrecked.
Subsequently I have left the house battery alone connected to a 20w solar panel with regulator and it has been fine.

 

[reeac]

My present batteries [Elecsol, ca. 5-6 years old] have never been disconnected or removed from the boat. I give them a 24 hour charge in December and again in April via the boatyard mains and the Sterling 20A. charger which takes maybe 2-3 kWh of mains power each time. This suggests to me that they've lost very little charge - maybe 5% per month - whilst sitting idle.

 

[guernseyman]

My two 10-year old batteries lose very little charge, but I charge them once a month and leave them on the boat so that the electronic stuff can be switched on and dried.

 

[BAtoo]

In the past with access to mains electricity I have left batteries connected over winter to a working "smart charger" with no problems.
Last winter with no mains access I left the 140AH battery connected to a 20W solar panel (mounted horizontally with clear view of the sky) with an on-off regulator and it was fine this spring.

 

[Boathook]

I leave mine on board and charge using mains when I go down. They're about 8 years old and still seem ok. I haver always done this and it does allow use of the 12 volt systems when I go down for the day.