What to do with boat batteries during winter storage?

Winnipesaukee Divers · 01-17-2006, 08:54 AM

Here's a story I found on another boating site... Boat batteries, who would have thought?

Posted By: Jud - s/v Sputnik
Date: 1/13/06 1:19p.m.

"Have just learned that a friend's house burned down last night --fire likely started by boat batteries in the basement that were being charged, though I don't have all the details yet. The woman is a keen Cal 20 racer and apparently had some batts trickle charging in the basement of her house. Fire started late last night; smoke alarm eventually went off, but she wasn't able to put out the blaze with a fire extinguisher b/c it was too big by the time she got to it. The house has essentially burned to the ground...all of her belongings gone, but her dog was saved. She still --alas--has her beloved boat, although it's to small to live on temporarily.

The follows immediately after my own shore power outlet/cable probably near miss with onboard fire...don't screw with electricity...and be goddamn careful if you have boat batts charging at home."

Follow up post:

"I crawled through the burnt out house yesterday helping my friends salvage whatever they could (not a whole lot) and I saw where the fire started, in a closet. It turns out that the batteries were not then being charged --it was a deep cycle batt that was being stored for a few months. So, gassing hydrogen from the battery likely wasn't the cause.

A thin wire metal storage shelf, the kind you buy at Ikea and screw into the wall in a closet for extra storage space, fell off the wall directly onto the battery --who knows whether or not the screws for the light shelf had wall anchors and fell, or if the shelf was overloaded and fell. Maybe both. Anyway, it clearly fell right onto the battery terminals, creating a dead short; the battery obviously got very hot and ignited things around it. There was no wiring or gas lines around where the fire started; and the shelf was fused/melted to the top of the battery, so this was the immediate conclusion I came too.

In short, don't put boat/car batteries inside your house... "

Well, I guess this makes my case when I say, "Just leave them in the boat, you'll do more harm to them by taking them out. Besides, batteries only last just a few years in a boat anyways."

jrc · 01-17-2006, 09:50 AM

Sounds like a tragic, but freak accident.

If you're going to store your batteries outside or on an unheated boat, make sure they stay charged. A fully charge battery will not freeze until about minus 90F but a 60% discharged battery will freeze at 0F. A fully discharged battery will freeze around 30F, its pretty much plain water at that point.

Kamper · 01-17-2006, 11:57 AM

Tragic but considerring the number of people who store batteries indoors (myself included) without incident, it's an extremely low-risk. Charging of course should only be done outside or in a properly ventilated area.

What site did this item come from?

Mee-n-Mac · 01-17-2006, 10:01 PM

jrc makes a good point about keeping your batt's charged up. I'll try to add something useful and say be careful what charger you use to do it. I have an old 2 stage charger that has a quickie charge up as well as a low current (? trickle ?) charge. However it says not to keep a battery on the "trickle" charge cycle for long periods of time as this will hurt the batt. The reason why is found in the link below. If you're going to leave the batt on a charger continually, it needs to be a "smart" charger.

http://www.batterystuff.com/tutorial_battery.html

Cal · 01-17-2006, 11:10 PM

I've left my batteries in the boat for years now by charging then the first weekend of each month wih the on board charger. Three years ago I discovered "battery tenders" , which do not charge the batteries but just replace what they need. Each one has an LED on it to indicate a charge. Kept my eye on it the first year and found about a 5 second charge every 15 minutes and that was only a few miliamps. It's not a timed process but rather monitors the battery for 12.7 volts. Turn anything on in the boat (like raise the power engine hatch and the battery that is turned on will stay lit a while.
This way there is virtually no explosive fumes and no boiling out of the electolyte and in the spring the ponies roar to life again.

01-17-2006, 08:54 AM	#1
Winnipesaukee Divers Senior Member Join Date: Apr 2004 Location: Exeter, NH or @ WCYC on weekends Posts: 250 Thanks: 7 Thanked 46 Times in 28 Posts	What to do with boat batteries during winter storage? Here's a story I found on another boating site... Boat batteries, who would have thought? Posted By: Jud - s/v Sputnik Date: 1/13/06 1:19p.m. "Have just learned that a friend's house burned down last night --fire likely started by boat batteries in the basement that were being charged, though I don't have all the details yet. The woman is a keen Cal 20 racer and apparently had some batts trickle charging in the basement of her house. Fire started late last night; smoke alarm eventually went off, but she wasn't able to put out the blaze with a fire extinguisher b/c it was too big by the time she got to it. The house has essentially burned to the ground...all of her belongings gone, but her dog was saved. She still --alas--has her beloved boat, although it's to small to live on temporarily. The follows immediately after my own shore power outlet/cable probably near miss with onboard fire...don't screw with electricity...and be goddamn careful if you have boat batts charging at home." Follow up post: "I crawled through the burnt out house yesterday helping my friends salvage whatever they could (not a whole lot) and I saw where the fire started, in a closet. It turns out that the batteries were not then being charged --it was a deep cycle batt that was being stored for a few months. So, gassing hydrogen from the battery likely wasn't the cause. A thin wire metal storage shelf, the kind you buy at Ikea and screw into the wall in a closet for extra storage space, fell off the wall directly onto the battery --who knows whether or not the screws for the light shelf had wall anchors and fell, or if the shelf was overloaded and fell. Maybe both. Anyway, it clearly fell right onto the battery terminals, creating a dead short; the battery obviously got very hot and ignited things around it. There was no wiring or gas lines around where the fire started; and the shelf was fused/melted to the top of the battery, so this was the immediate conclusion I came too. In short, don't put boat/car batteries inside your house... " Well, I guess this makes my case when I say, "Just leave them in the boat, you'll do more harm to them by taking them out. Besides, batteries only last just a few years in a boat anyways."

01-17-2006, 11:57 AM	#3
Kamper Senior Member Join Date: Jul 2005 Location: Thornton's Ferry Posts: 1,296 Thanks: 67 Thanked 166 Times in 126 Posts	Not even safe to hide in a closet these days? Tragic but considerring the number of people who store batteries indoors (myself included) without incident, it's an extremely low-risk. Charging of course should only be done outside or in a properly ventilated area. What site did this item come from?

01-17-2006, 10:01 PM	#4
Mee-n-Mac Senior Member Join Date: Sep 2003 Posts: 1,943 Thanks: 23 Thanked 111 Times in 51 Posts	Charging batteries jrc makes a good point about keeping your batt's charged up. I'll try to add something useful and say be careful what charger you use to do it. I have an old 2 stage charger that has a quickie charge up as well as a low current (? trickle ?) charge. However it says not to keep a battery on the "trickle" charge cycle for long periods of time as this will hurt the batt. The reason why is found in the link below. If you're going to leave the batt on a charger continually, it needs to be a "smart" charger. http://www.batterystuff.com/tutorial_battery.html __________________ Mee'n'Mac "Never attribute to malice that which can be explained by simple stupidity or ignorance. The latter are a lot more common than the former." - RAH

01-17-2006, 11:10 PM	#5
Cal Senior Member Join Date: Apr 2004 Location: Pitman , NJ Posts: 627 Thanks: 40 Thanked 21 Times in 12 Posts	I've left my batteries in the boat for years now by charging then the first weekend of each month wih the on board charger. Three years ago I discovered "battery tenders" , which do not charge the batteries but just replace what they need. Each one has an LED on it to indicate a charge. Kept my eye on it the first year and found about a 5 second charge every 15 minutes and that was only a few miliamps. It's not a timed process but rather monitors the battery for 12.7 volts. Turn anything on in the boat (like raise the power engine hatch and the battery that is turned on will stay lit a while. This way there is virtually no explosive fumes and no boiling out of the electolyte and in the spring the ponies roar to life again. __________________ Paddle faster , I think I here banjos Last edited by Cal; 01-19-2006 at 09:32 AM.

01-17-2006, 09:50 AM	#2
jrc Senior Member Join Date: Apr 2004 Location: NH Posts: 2,689 Thanks: 33 Thanked 439 Times in 249 Posts	Sounds like a tragic, but freak accident. If you're going to store your batteries outside or on an unheated boat, make sure they stay charged. A fully charge battery will not freeze until about minus 90F but a 60% discharged battery will freeze at 0F. A fully discharged battery will freeze around 30F, its pretty much plain water at that point.