Shop fires from Bat chargers and extension cords

[Domenic T.]

First one was a 12V battery I washed and put out side to dry. All connections were CORRECT and the selector was set at 12V. About 1 hour the area filled with smoke and I unplugged the cord. Bat was not reverse pollarity when I started.
2nd was the same, Suburban hatch was open and bat got low. @ hours into the charge same thin wit the same kind of charger.
Next one was a extension cord that caught fire about 5" from the car cover on my 67 vette. That was inside the shop and the cord must have been damaged and I was there to put the fire out.
Now I only charge outside or when I am there to keep a eye out.

Dom

[Terry M.]

Re: Shop fires from Bat chargers and extension cords

First one was a 12V battery I washed and put out side to dry. All connections were CORRECT and the selector was set at 12V. About 1 hour the area filled with smoke and I unplugged the cord. Bat was not reverse pollarity when I started.
2nd was the same, Suburban hatch was open and bat got low. @ hours into the charge same thin wit the same kind of charger.
Next one was a extension cord that caught fire about 5" from the car cover on my 67 vette. That was inside the shop and the cord must have been damaged and I was there to put the fire out.
Now I only charge outside or when I am there to keep a eye out.

Dom

I have heard from Insurance Adjuster (who doesn't wish to be quoted) that the first thing they look for in garage fires is battery chargers. Not just automotive batteries, but portable hand tools as well.

Unfortunately most (all) of these chargers are made in countries with poor quality controls.

[Dick W.]

Re: Shop fires from Bat chargers and extension cords

I have heard from Insurance Adjuster (who doesn't wish to be quoted) that the first thing they look for in garage fires is battery chargers. Not just automotive batteries, but portable hand tools as well.

Unfortunately most (all) of these chargers are made in countries with poor quality controls.

The very reason all my portable tool chargers are on a metal shelf with no flammables within 18". I mount trickle chargers on metal as far away from combustibles as possible. When I did fire investigations for my county I saw a couple of fires that could be attributed to batteries/chargers

[James B.]

Re: Shop fires from Bat chargers and extension cords

For this reason, I even keep a close eye on my float charger and disconnect it when finished charging.

[Domenic T.]

Re: Shop fires from Bat chargers and extension cords

Dick,
I fly RC airplanes with re-charge batteries and also charge hand tool Batteries. I also do your method of keeping them away from any thing that can burn. I charge some in used 5 gallon metal buckets. Most of my shop is not insured and I need to eliminate any hazard.

Dom

[Gary R.]

Re: Shop fires from Bat chargers and extension cords

Good info, I only recharge my cordless tools while I am in the shop and unplug them when leaving. I do leave my battery tender plugged in 24/7 and have for years without a problem. Rarely use extension cords and only when in control of the area. Scary when extension cords are used with electric heaters, beware of over heated conductors.

[Stephen R.]

Re: Shop fires from Bat chargers and extension cords

Had a battery in the basement on a "maintainer" that i used when I needed a 12V source. blew up, blew out the side. That was a fun clean up/ Tons of baking soda/

[Jeffrey S.]

Re: Shop fires from Bat chargers and extension cords

Dick,
I fly RC airplanes with re-charge batteries and also charge hand tool Batteries. I also do your method of keeping them away from any thing that can burn. I charge some in used 5 gallon metal buckets. Most of my shop is not insured and I need to eliminate any hazard.

Dom

I also have rechargeable batteries for my u-control model planes and charge them inside a metal cash box just in case. I have had a multiple connector charger "explode" shooting flames. Scary. I have several cars in my shop on Battery Tenders/Minders and all are far away from combustibles.
Jeff

[Philip C.]

Re: Shop fires from Bat chargers and extension cords

. Some good advice above, every battery should have a switch on the positive post. Please don't leave you battery connected to your car at ANY time unless your driving it. Take it to church, turn off that switch , in transport, in storage turn off that switch. TELL the transporter to turn that switch OFF also. I can't tell you how many times at car shows I've seen that the battery were connected during transport. Mice can get in your car at any time and they need to chew and electrical wire they like to chew. Also never leave those battery tender type chargers on when your not there. A friend of mine lost his car and half his house from a electrical spike that fried his battery charger that was connected to his car. I tell all my car friends esp the ones that are not too handy, to put white cardboard under their car(s) and to check it often. Phil

[Mark E.]

Re: Shop fires from Bat chargers and extension cords

White cardboard?

[Philip C.]

Re: Shop fires from Bat chargers and extension cords

Hi Mark It's real easy to spot leaks of any kind with white card board. (sorry I guess I should have expanded on it above) Phil

White cardboard?

[Frank D.]

Re: Shop fires from Bat chargers and extension cords

. Some good advice above, every battery should have a switch on the positive post. Please don't leave you battery connected to your car at ANY time unless your driving it. Take it to church, turn off that switch , in transport, in storage turn off that switch. TELL the transporter to turn that switch OFF also. I can't tell you how many times at car shows I've seen that the battery were connected during transport. Mice can get in your car at any time and they need to chew and electrical wire they like to chew. Also never leave those battery tender type chargers on when your not there. A friend of mine lost his car and half his house from a electrical spike that fried his battery charger that was connected to his car. I tell all my car friends esp the ones that are not too handy, to put white cardboard under their car(s) and to check it often. Phil

That would be on the "negative" post; John Hinckley has posted the reasoning many times here and elsewhere...

[Terry M.]

Re: Shop fires from Bat chargers and extension cords

That would be on the "negative" post; John Hinckley has posted the reasoning many times here and elsewhere...

I know and respect John, but I have worked in the electrical distribution field for almost 50 years. I could explain why John believes negative disconnects are better, but it really doesn't make any difference from an electrical point of view which polarity is disconnected. Once a circuit is opened, it is no longer a circuit.

One should use whichever pole is easiest to install and/or disconnect. The ease of mechanical operation is much more significant than which pole is disconnected.

[Frank D.]

Re: Shop fires from Bat chargers and extension cords

I know and respect John, but I have worked in the electrical distribution field for almost 50 years. I could explain why John believes negative disconnects are better, but it really doesn't make any difference from an electrical point of view which polarity is disconnected. Once a circuit is opened, it is no longer a circuit.

One should use whichever pole is easiest to install and/or disconnect. The ease of mechanical operation is much more significant than which pole is disconnected.

I don't disagree (entirely) but most disconnects are sized to go on the negative battery terminal...
I have maintenance chargers on my classic cars, a jet ski and a boat and its never been a problem...
I've had two fail over the decades but never in a catastrophic manner..

Most home burglar alarms have a battery backup (a motorcycle style battery in many cases) that is charged via similar circuitry and if folks are that paranoid those should pose a problem for them I would think

[Domenic T.]

Re: Shop fires from Bat chargers and extension cords

Frank,
I guess things happen. I had a shop alarm up high so it could not be reached without a ladder. It was in a metal box. Truthfully I had 2 blow up one in my face that put me in the hospital which (i think) caused more damage on a 15 min eye flush than the acid. 3 blow up in airplanes. and 1 in a motorcycle in the last 40 years. I am careful where I put them.
My friend was taking one out of his airplane and it blew, no acid, it was a sealed battery and Concord replaced their battery. I called Concord and said their battery did not have acid in it, and they said they do not put acid in lead acid batteries any more and discontinued batteries that had caps on them. They have special fibre that keeps a acid film on the plates.
The ni-cad batteries were required to have temp sensors on them which had 2 warning lights one @ 140 and the other @ 180. The alumination ment instant action. They were in SS sealed boxes and a thermal runaway was supposed to be contained in the box with a vent to the outside. I read where one blew the box and caused a fatal crash.
The one that got me in the face was a post failure inside the battery that caused a spark when I tightened the side post.
But, the stool in the kitchen hurts more people than batteries!

Dom