A local family here in NJ lost their house to a fire this past week. Heard from a local he had a dodge viper in the garage on a battery tender. The fire started there and they think it was the battery tender.
How can I maintain my tender? Buy a new one every couple years? Make sure its a reputable brand or are they all made in the same factory.
Pics of the fire from fire department
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With modern battery technology (i.e. that which would be in a Viper) and modern battery tenders, this is a freak accident. Our neighbor's house burned to the ground attributed to the mini dorm fridge they kept out by the pool.
I don't see how you can proactively prevent something like this. I have a car in the garage on a tender and not giving it a second thought.
I bet it had less to do with the actual battery tender. Something probably got shorted between the battery terminals. If you orient the clamps on my tender leads incorrectly, you could actually make them touch. I could see the thin rubber coating getting scratched or wearing off, thin enough to melt, the clamps short together, maybe a little weld splatter action, and it drips onto an oil spot or cardboard or piece of carpet (fancy looking garage from the photos).
Looks similar to what happened to one of my BIL's friends. He was charging his drone batteries in his garage when one of them shorted out and started a fire. I think it's one of those deals where any place there's electricity, there's the possibility of fire.
IMO, if you inspect the wiring and make sure you have good, solid connections, you have nothing to worry about.
All makes sense. Just heard it could happen over the years and with my family, thought I'd look into it more. Luckily everyone made it out alive but if it happened at night, its a scary thought.
I use a ctec and a battery tender brand. I tend to replace when they get haggered.
I think a quick disconnect battery terminal is a much better option. Sure the battery will still eventually lose its charge, but that's more of an issue for non-op vehicles. You could still trickle-charge those batteries periodically though, just to keep them from fully discharging.
Pete Gossett (Forum Supporter) said:
I think a quick disconnect battery terminal is a much better option. Sure the battery will still eventually lose its charge, but that's more of an issue for non-op vehicles. You could still trickle-charge those batteries periodically though, just to keep them from fully discharging.
If it's a modern-ish car, there are plenty of electronics related reasons not to disconnect the battery all the time, however. ECU loses its memory, plus potential convenience features.
I generally don't worry too much about battery tenders, but I do give them a touch to confirm normal temperature, etc. any time I'm in the garage. And I do occasionally check battery temperature on any vehicles that are hooked up to make sure they're not suffering a battery failure that could turn into a meltdown.
How about something like this to stop the fire if it starts.
BlazeCut
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I lost a toterhome to a mouse chewing the wire to a small ceramic heater. You could see the spot of origin on the carpet where the wire was chewed.
My first battery tender was the motorcycle model with the SAE connector. This allows permanent install of a connector so you never can have clamps accidentally short out. It makes things easier in addition to being safer if someone trips over the leads.
matthewmcl (Forum Supporter) said:
My first battery tender was the motorcycle model with the SAE connector. This allows permanent install of a connector so you never can have clamps accidentally short out. It makes things easier in addition to being safer if someone trips over the leads.
Good point. The Battery Minder units I've got currently came with leads like this. I installed a set on each of my cars and the snowblower, so I can just plug in whatever I need to without fussing with clamps. The units I've got are also temperature compensated, so they'll charge better in the cold and less risk of cooking a battery (or blowing one up from cooking off the electrolyte) in hot weather.
matthewmcl (Forum Supporter) said:
My first battery tender was the motorcycle model with the SAE connector. This allows permanent install of a connector so you never can have clamps accidentally short out. It makes things easier in addition to being safer if someone trips over the leads.
Agreed. All my motorcycles and most of the not-for-daily-use cars I have have the pigtail hardwired to the battery. I pretty much only use the clamps in an emergency.
kb58
SuperDork
12/29/20 10:26 a.m.
To the OP, if you still don't trust the tender itself, just put it in a coffee can, which will control any flameage.
kb58 said:
To the OP, if you still don't trust the tender itself, just put it in a coffee can, which will control any flameage.
I would recommend against this. Any flame can melt insulation and then short out through the can. Try a small ceramic flowerpot for jobs like this.
I have heard of a few other exotic cars getting toasted with a battery tender fire ,
I would be even more worried about a cheap tender from Harbor Freight or some no name Ebay seller.
but is it the Tender that overheats and catchs fire , or the 12v battery that shorts because Tender did not turn off ?
In reply to californiamilleghia :
You don't short because it doesn't turn off (I don't think) and if you did short internally you bypass the power generating reaction and just go to a brick (plates shorted together). Charging (and overcharging) do generate hydrogen gas. To actually catch something on fire, though, seems like it would take an extended heat input, rather than a flash, so I doubt the hydrogen could do it.
matthewmcl (Forum Supporter) said:
In reply to californiamilleghia :
You don't short because it doesn't turn off (I don't think) and if you did short internally you bypass the power generating reaction and just go to a brick (plates shorted together). Charging (and overcharging) do generate hydrogen gas. To actually catch something on fire, though, seems like it would take an extended heat input, rather than a flash, so I doubt the hydrogen could do it.
The issue isn't directly the hydrogen released from charging. If you cook off too much electrolyte, you can get a large pocket of hydrogen in the battery casing and have it actually explode while charging.
In reply to rslifkin :
Clearly that would make a huge mess and I might need new underwear if I was near it, the acid is dangerous being flung around, but would there really be enough heat to start an underhood fire? Seems like a newish car would not have fuel leaking. Exploding battery breaks a fuel line? A direct short somewhere just requires fewer faults.
I use the Optima charger. This thing will auto click off it senses anything crazy. It also has the permanent install style connectors. This is also something that we should not set and forget. When I have my Miata on the charger I check the connectors and everything daily
11GTCS
HalfDork
12/29/20 12:18 p.m.
matthewmcl (Forum Supporter) said:
My first battery tender was the motorcycle model with the SAE connector. This allows permanent install of a connector so you never can have clamps accidentally short out. It makes things easier in addition to being safer if someone trips over the leads.
This, no alligator clamps. The one in my Mustang is permanently wired to the battery terminals and has a polarized quick connect plug with cap and a fuse in the line.
matthewmcl (Forum Supporter) said:
In reply to rslifkin :
Clearly that would make a huge mess and I might need new underwear if I was near it, the acid is dangerous being flung around, but would there really be enough heat to start an underhood fire? Seems like a newish car would not have fuel leaking. Exploding battery breaks a fuel line? A direct short somewhere just requires fewer faults.
I had one of my RV house batteries (very large deep cycle type) explode and you're right, it makes a hell of a mess. There are actually two batteries in parallel. Only one blew. I had never experienced anything like it. Fortunately I was not nearby, and actually did not know it had blown. I was in my shop about 100 yards away and I HEARD it blow, but didn't know what the sound was. The closest thing I had heard to the sound was firing my .270 rifle, which is LOUD. I live in the woods and thought I had a trespasser. Anyway, I later discovered the battery had blown when I saw chunks of the casing and a puddle of acid under the RV. It didn't start a fire, but I can see where it could have if there had been more flammable material in close proximity. It was not on a charger at the time although I usually keep it in a Minder. Not sure what set it off but I'll never forget it.