Don't Stab A Phone Battery With A Knife

Ooooh, makeshift incendiary devices! I wonder if it's hot enough to ignite thermite. :D
 
You think that is bad, google "lipo fire" and watch some youtube videos.

BTW, not all phone batteries will do this. It depends on the specific chemistry. Lipo may or may not smoke and/or explode. Li-Ion generally won't do much at all. I've been into RC cars for a long time and we always have to be careful with our Lipos. Even discharging them too much can cause a violent reaction/fire.
 
Its the short circuit that does it, not the exposure to air. It actually contains its own oxidizer as I recall when I was doing some research for a class project. You can't put out Li Ion fires with a fire extinguisher, you certainly don't want to put it in water, you gotta bury it in sand.
 
Also, first person to do this on a commercial airplane wins the award of making everyone forever after have to turn in their phones, tablets, and laptops to a central bin for the flight. Everyone has a phone with Li Ion batteries and keys are sharp enough, it just takes one crazy person to actually do it on a flight.
 
EODetroit said:
Also, first person to do this on a commercial airplane wins the award of making everyone forever after have to turn in their phones, tablets, and laptops to a central bin for the flight. Everyone has a phone with Li Ion batteries and keys are sharp enough, it just takes one crazy person to actually do it on a flight.
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Yeah, this has certainly isn't an unknown but if you took people's gadgets away on a plane you might be facing a greater threat.
 
EODetroit said:
Its the short circuit that does it, not the exposure to air. It actually contains its own oxidizer as I recall when I was doing some research for a class project. You can't put out Li Ion fires with a fire extinguisher, you certainly don't want to put it in water, you gotta bury it in sand.
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what happens when you put it in water? Or do you mean, that won't do anything because it'll burn in water as well, since I'm almost sure it will.

Wouldn't it glassify the sand?
 
pothb said:
what happens when you put it in water? Or do you mean, that won't do anything because it'll burn in water as well, since I'm almost sure it will.

Wouldn't it glassify the sand?
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Lithium reacts extremely violently with water.

The sand/glass, if it's hot enough to make glass, would cut off oxygen to the fire.
 
Laureolus said:
Lithium reacts extremely violently with water.

The sand/glass, if it's hot enough to make glass, would cut off oxygen to the fire.
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Didn't know it reacts badly to water.


And I guess I overestimated lithium's heat.
 
I never tried anything with a cell phone battery but I've taken a propane torch to coin lithium batterys before. It's fun but eye/hand protection is a must.
 
I'm now reminded of that poor girl that had her Galaxy S III in her pocket when the battery exploded.
sclatter.jpg

Fanny-galaxy-s3-verbrennungen.jpg
 
Ouch :(.

I had my phone shutdown while I had it charging in my car in the summer.....I was afraid to have the phone in my pocket and order a new one the same day.
 
Hmm my iPhone's been doing some weird shit lately like powering down at 18% and not turning back on until I plug it in. Maybe it will explode in my pocket and I can get some time off.
 
Laureolus said:
Lithium reacts extremely violently with water.

The sand/glass, if it's hot enough to make glass, would cut off oxygen to the fire.
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There is a bigger problem with lithium based batteries in water, and that is the chance of a dead short which well DEFINITELY cause smoke/fire/explosion. I know that water isn't terribly conductive on its own but even moderately minerilized tap water, if it gets inside the battery where the + and - may only be separated by a millimeter can cause some serious shit for sure.

That being said I have run lipo batteries fully submerged in river water with nothing more than some liquid tape protecting the non-heat shrunk parts of the battery and never had a problem.
 
Can't edit: I am talking about a 6s (22.2v nominal voltage, 25.2v full charge) for the dunking in water.
 
That explosion is just the result of the freeing of hundreds of sweatshop kids' souls. Modern cellphones run on them.
 
ramrod126 said:
You think that is bad, google "lipo fire" and watch some youtube videos.

BTW, not all phone batteries will do this. It depends on the specific chemistry. Lipo may or may not smoke and/or explode. Li-Ion generally won't do much at all. I've been into RC cars for a long time and we always have to be careful with our Lipos. Even discharging them too much can cause a violent reaction/fire.
Click to expand...

We punctured a couple of 2S lipo packs and we just got a lot of smoke and no fire.
But I have seen some vids on youtube of lipos catching fire after crashes.
 
Zepher said:
We punctured a couple of 2S lipo packs and we just got a lot of smoke and no fire.
But I have seen some vids on youtube of lipos catching fire after crashes.
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The massive fires are usually caused by purposeful overcharging. Some folks even put full 110 mains power into them. The truth is that as long as you are even moderately careful you won't have a problem...unless you get a bad pack from the manufacturer. In 12 years of RCing I have never had a lipo go unless I made it go.

I have, however, had a couple NiCad packs get so hot they melted some plastic on the chassis of the RC.
 
Most of the time its not that easy to get a lipo to flame ( i once crashed a plane with 4S (16V) 4000MAH that was nearly full and we just couldn't get it to really do more than subtle smoke.

The point of this video is really just that Lithium and especially LiPo batteries are high energy density and relatively sensitive and should be treated with respect.
 
Actually it is very well known in the aviation world. Sometimes planes carry cargo full of lithium ion batteries, which can be pretty dangerous. I actually think I read that that Malaysian airline was carrying cargo containing them. I'd have to double check that though.
 
Who even ponders stabbing a battery with a knife intentionally? :eek: That's not something that just pops into a normal person's mind. Like they're sitting around looking at a battery thinking, "Hey, I have an urge to get a knife and stick it into that thing." You'd have to be sort of warped to begin with and are kinda likely to be featured in a Darwin award someplace.
 
So much for my "Recycled Cell Phone Batteries for Prison Guards Anti-Shank Vests campaign.
 
I imagine that the Tesla vehicle batteries when punctured do the same thing? :eek:
 
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