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Lithium-Ion Batteries Linked to Airplane Fires
Posted by
timothy
on Mon Jul 17, 2006 03:48 PM
from the mine-keep-not-exploding dept.
from the mine-keep-not-exploding dept.
smellsofbikes writes "The National Safety Transportation Board thinks it's possible that lithium-ion batteries caused a fire that destroyed a United Parcel Service airplane on Feb 8, 2006. The FAA already bans non-rechargeable lithium batteries from air shipment because aircraft don't carry fire suppression equipment capable of extinguishing lithium fires. The interesting thing is: these batteries aren't being used or charged, they're just being shipped: spontaneous battery combustion. Is this something that happens in the back of computer stores, or just on airplanes?"
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squished? (Score:2, Interesting)
Re:squished? (Score:2, Interesting)
Re:squished? (Score:5, Interesting)
Parent
Re:squished? (Score:5, Informative)
Parent
Re:squished? (Score:3, Informative)
The problem is that already-charged lithium batteries contain a lot of energy, and if they short out, they will heat up fast.
A new, uncharged rechargeable battery, on the other hand, is basically a dead battery. Short it out and nothing happens.
Here's something you can try at home if you're a total skeptic: charge up your cell-phone battery, remove it from your phone and drop it in your pocket along with some change or a set of keys, and go for a walk. You'll KNOW when the battery shorts ut.
Re:squished? (Score:3, Interesting)
Re:squished? (Score:4, Informative)
The article pointed out thes are non-rechargeable lithium batteries - the disposable type you put in cameras, etc. They're fully charged when manufactured, so there's no way to ship them in even a partially-discharged state. When a new one goes, either from design defect, poor quality control, or mishandling, it REALLY goes.
Also, you CAN completely discharge a rechargeable lithium battery and then recharge it. (How do I know it was completely discharged? Stupid me put it in my pocket with change and keys - so you KNOW that it got shorted out at some point - but it was totally dead, so no harm done). The recharging circuitry isn't supposed to let you recharge a completely dead battery (the battery will get REALLY warm, for example), but I've done it. That particular cell phone battery is now 5 years old, been through well over its rated maximum charge/discharge cycles - 500, and still keeps a 50% or greater charge (though for a while it would keep hardly any charge at all).
Parent
Re:squished? (Score:4, Insightful)
Assuming you're talking about a fairly modern battery, it probably wasn't completely discharged. Most modern Li-Ion batteries contain a voltage regulator and a low-voltage cutoff. If the voltage drops below a certain point, they cut off power flow out of the battery to prevent you from destroying it by fully discharging it.
Parent
Re:squished? (Score:5, Interesting)
Parent
Re:squished? (Score:3, Funny)
Re:squished? (Score:4, Informative)
I doubt the liio batteries are catching fire due to taking on water. They WILL however explode if placed in a fire, as all rechargeable batteries have a warning label on them to not dispose of in fire and that is why. If the pack is badly designed and somehow several of the cells are allowed to short, such as if the recharge control chip shorts out, this can lead to the batteries dead shorting. (this is only an issue if the cells are charged, which as I mentioned is pretty much assured) Any rechargeable battery (liio, nimh, or nicd) will get extremely hot when dead shorted while charged, as all the energy of its charge is rapidly released. (most laptop batteries are around 50 watts normal discharge, which can translate easily into 200-300 watt discharges when shorted) Liio carries the additional penalty of being more prone to explosion when superheated, and this can lead to them exploding if shorted.
Though in this article it does not sound like explosion was an issue, more fire. This probably means a pack shorted out (defective, failed) and overheated, catching its battery case on fire due to heat. The burning case eventually helped raise the battery temperature enough to lead to the ignition of the battery electrolyte. (the lithium itself) Once a pallet of liio batteries starts on fire, fire suppression really doesn't matter any more. When the fire department has to deal with things like that they don't try to put it out - they just get everything flammable away from it and cover it with water to suppress the heat until it burns itself out. Once the lithium goes from merely hot to actually burning, you cannot smother it with water, it will rip the oxygen right off the water molicules to continue to burn. So the plane's fire suppression system would have actually fed such a fire. Foam (or something solid) is about the only thing that has a chance of suppressing a lithium fire, and even that is not very effective due to the intense heat of burning lithium vaporizing the foam. (it takes a lot of foam)
Parent
Re:litte kid asks.. "how did you loose your leg" (Score:3, Funny)
I figure anyone who actually tries it deserves one of these [darwinawards.com]
Kind of like the oakie who went to the doctor for a vasectomy:
Re:squished? (Score:3, Insightful)
Whatever for?
If it wasn't for the Society, there would be nobody to get "First Post"!
Re:squished? (Score:2)
Re:squished? (Score:3, Interesting)
I've taken apart a few lithium coin batteries. They have a soft metalic square of what I believe lithium on one of the plates. The metal is soft, can be easily cut and oxidizes from its shiny appearance to a dull grey in seconds. It can be easily ignited into a very bright light which seems brighter than the sun. Also, it can be dropped into a cup of water and it skeeters around lik
Environmental stress (Score:5, Informative)
Re:Environmental stress (Score:5, Informative)
Parent
Nope, it happens in plenty of places (Score:5, Informative)
http://www.candlepowerforums.com/vb/showthread.ph
http://www.candlepowerforums.com/vb/showthread.ph
There have been several documented "venting with flames" of primary CR123A batteries. Rechargeables seem to be a lot more stable, occasional Dell laptop conflagarations notwithstanding.
Re:Nope, it happens in plenty of places (Score:5, Informative)
Lithium primary cells generally do not have construction compatible with fast discharge. Often it can be gotten away with if the discharge is under 0.6C or is of a pulsed nature. Continuous discharge will kill them tho, a flaming, explosive kill.
Batteries have ever-increasing power densities, and deserve respect from designers. Just tossing 123s in is a BAD idea IMO. I was an engineer on a project where someone did just slap one in without consideration. When we put the test unit through its paces, blammo. Pulling 2A out of a 1.5A battery for 7 seconds is OK in NiCads and NiMH cells and even rechargable LiPoly prismatics if you know what you're doing. This was a dime store photo battery, and it went off like a small cannon after a few seconds.
People don't think about the design envelope for batteries as much as they should any more. It's unfortunate.
My US$0.02 as an engineer.
Parent
Re:Nope, it happens in plenty of places (Score:4, Funny)
Where on the geek scale does *that* fit?"
Oh, they're some of the brightest geeks you'll find.
Parent
Re:Nope, it happens in plenty of places (Score:3, Informative)
The question I'm more interested in is.... (Score:3, Interesting)
Re:The question I'm more interested in is.... (Score:4, Interesting)
False sense of security? Hell yes.
Parent
UPS = Ooops (Score:5, Interesting)
Given how some of my UPS packages arrive looking like they were dragged to my house behind the truck, I would say that it is pretty likely that UPS is doing things to the batteries that my computer store doesn't.
Re:UPS = Ooops (Score:4, Informative)
To make a long story short, we were not particularly gentle with the packages. In fact if you saw the way the trucks were loaded, you'd be surprised at what good conditions your packages are in. I still use UPS, but I always make sure that things are packed very, very well.
Parent
Re:UPS = Ooops (Score:4, Interesting)
And for those who are wondering what this guy means, what he means is that the back of the truck gets loaded, with boxes stacked. Then the front of the truck gets loaded, by throwing boxes over the top of the boxes right in the back of the truck.
One of my buddies used to work for UPS in Santa Cruz, CA. They had a chute that the packages came down, about ten feet long, and crashed onto the conveyor belt, from which point they threw them at the trucks. The chute had a big nasty bolt sticking down in the top of it, and occasionally large packages would get stuck on the bolt, gouging big holes in 'em. Someone would have to climb up the shaft, and unclog it.
Parent
It may not be UPS (Score:3, Interesting)
Some things only happen on airplane crashes.
Pressure? (Score:3, Interesting)
Now, when you're on a commercial flight cruising along at 33,000ft, you may only be pressurised to 9,000ft and this, of course, includes your hand luggage.
Is it possible that the depressurisation to 9,000ft alt and the repressurisation on landing resultant expansion and compression cycle of the lithium batteries and causing them to somehow fail?
Close Call... (Score:3, Funny)
Warning... (Score:5, Funny)
They are charged (Score:2)
Spontaneous Lithium Battery Fires (Score:4, Informative)
I've seen it with my own eyes. I wrote the embedded software (8051 C) for a robotic bone lengthener / deformity corrector in the early 90's, it was powered by Lithium batteries that ran the motors and provided 5V for all the electronics. On more than one occasion (during development) we had Lithium batteries just go up in fire and smoke, for no apparent reason. It caused us a lot of worry to say the least, especially since any bad and ready to blow cells were packed into packs with surrounding cells.. to add to the fire. This was 12 years ago, so I am sure Lithium batteries are better than ever, but it doesn't suprise me to hear about them going up in flames.
Re:Spontaneous Lithium Battery Fires (Score:3, Interesting)
Now, as I said, I don't know much about lithium batteries, but batteries in general use chemical processes to
Fragile (Score:5, Funny)
Fragile (fra-gil-lay) from early French n. To toss about with reckless abandon.
I smell a fire^w new movie plot (Score:3, Funny)
"Li-ons on planes"
lipo fires (Score:4, Informative)
Here is an informational thread about lipo batteries:
http://www.rcgroups.com/forums/showthread.php?t=2
Uh... "Vent with Flame" anyone? (Score:5, Informative)
Li-Ion batteries are extremely volatile and sensitive, which is why good batteries have a variety of protective circuits on them (or can have) - e.g., physical distortion (detects if the battery balloons), over temperature (charging/discharge), over current, unsafe low voltage (if the battery voltage falls too low, you can't charge it safely), and many more. That's also why their charge regimen is so complex (charge at constant current to ~90% capacity, then constant voltage charge to 100%. Then stop all charging until capacity is around 90% again, then restart CV charge - this is why the first 80% can happen relatively quickly, while the last 20% can often take as long as it took to get to 80% in the first place) since they need charge controllers and "smart chips" to monitor the state of the battery.
Usually these events happen when the battery is actually used, but there isn't anything to say that it can happen otherwise. Those protective circuits require power, and they get their power from the battery while outside the device. And since you cannot store Li-Ion batteries discharged very well, they are often charged at the factory, during assembly and final sale. A nice short somewhere along the line and battery will vent with flame.
There's a reason why most LiIon batteries have hard to get at terminals or come with protective covers. It's not for convenience, but more for during storage/shipping, so the terminals don't get shorted.
Oh yeah, those protective circuits are optional - not all batteries have every one (some may not need it or find a way to protect it in another way - battery distortion can be handled by having the battery having to fit in a slot - if it can't fit, well...). Third party ultra cheap batteries may have *no* protective circuits at all (hence those "Nokia Exploding Batteries").
Re:Uh... "Vent with Flame" anyone? (Score:4, Informative)
R/C circles probably have the largest percentage of failed Lithium Polymer batteries, because they are discharged at pretty high rates, and the protective circuits on most consumer lithium batteries are removed. Most failures are caused by the following:
- Overcharging due to the use of a bad charger or using the wrong settings on a Lithium-Polymer-capable charger.
- One cell of a multicell pack overcharging due to being at a higher initial voltage than the other cells in the pack. This is being mitigated with the use of "balancers" which connect to each cell and maintain equal voltages across the pack.
- Physical damage due to crashes.
- Shorting out the battery.
- Allowing the voltage of a cell to drop below 3.0V.
Many of these have been ameliorated due to technological improvements in the last two years - for example the aircraft-side electronics now cut off the motor at a point where the battery voltage is still safe, chargers have been much improved, and battery packs now come with special connections to allow checking and adjusting voltages on a cell-by-cell basis.
R/C enthusiasts tend to treat Lithium-Polymer batteries with quite a bit of respect as far as storage and charging is concerned. Many will set up a cinderblock on a concrete floor, place the battery in one of the holes of the cinderblock (the holes in the block are set vertically) and cover the top of the hole with a plastic bag full of sand. In case of a "vent with flame", the heat will melt the plastic allowing the sand to cover the battery and put out the fire. Compared to a couple of years ago, however, the incidence of Lithium-Polymer fires has greatly decreased even as use of Lithium-Polymer batteries has increased.
This forum thread [rcgroups.com] has a lot of information about dangers and safe handling guidelines for Lithium-Polymer batteries.
Parent
More on the destructive power of Lithium.... (Score:5, Informative)
In related news... (Score:3, Funny)
1st, damage/etc in shipping process, THEN fire (Score:3, Insightful)
This is also why there aren't lots of fires in the backrooms of computer stores. All those laptops not only don't have charged batteries but they've probably already been inspected for damaged packaging.
Atleast that's my theory.
LoB
So what's the altitude/temperature tradeoff? (Score:3, Interesting)
With all that said, it's unsettling that a battery has *anything* going on in it when it's just sitting there in a brown paper box. Do Li-ion batteries have vents, like old lead-acid batteries? Can they evolve gas? (If so, what happens to their chemistry afterwards? it's not like they can recapture hydrogen offgassed: do they lose efficiency over time from this?)
I know much less about batteries than I thought I did.
Re:It's not the pressure (Score:3, Insightful)
I don't know if I'd categorize that as a "modest" drop. That's 1/3 of an atmosphere. That's low enough pressure to manifest measurable, visible symptoms of hypoxia in humans not accustomed to the high altitude. Airplanes are forbidden from flying above 10,500 MSL for more than 30 minutes without carrying oxygen. Living at 11,000 full time would definitely affect sea-level folk, and I don'
Totally Possible... (Score:3, Interesting)
They are great batteries that are light with lots of power, but they are quite finicky. I always charge as slow as possible and use a temp probe to shut everything down if it gets too hot.
All that being said, I wonder how they could ignite if they are not in a charge or discharge (besides normal dishcharge as they sit unused) while in a cargo hold. I would think (no, I did not RTFA but hey this is Slashdot) they would need to be mutilated or highly disturbed in some way to catch fire.
With fires like these, (Score:3, Insightful)
Exploding digital cameras (Score:3, Interesting)
Back around 1992, I used to work for a Kodak dealer who sold the Kodak DSC200 series digital cameras. They were a Nikon 35mm camera body with a digital film back and Li based rechargable battery pack.
My boss was on a client site setting up to run a demo, these cameras cost AU$30k each, it was sitting on a counter waiting to be hooked up when it burst into flames.
While I wasn't present for the actual fire, I did see the melted unit afterward when packing it to be sent back to Rochester for tests.
This has been a *known* issue for a very long time.
Re:Too slow? (Score:5, Informative)
Parent
Better yet, banned from cargo. (Score:2)
Re:Incapable of extinguishing? (Score:4, Informative)
* For small fires involving the battery [extinguishing] media such as Lith-X or copper powder may be used, but should be applied with a long handled tool. Do not use CO2 or Halon directly on a battery fire as the exposed surface of the contained lithium may react with these materials.
* For larger fires involving lithium batteries, copious amounts of water may be applied, from a safe distance, to control the fire and protect adjacent materials and facilities.
Simply put, water won't do the trick. It may contain the fire (by dousing the flames / removing its heat from the equation), but it won't extinguish it. Also, dumping water onto a battery fire just causes a lot of steam. Depending on the size of fire and the amount of water (since the key term used above is copious), you could turn a sealed airplane into a pressure cooker in just a few minutes, and no one is going to be happy about that.
Parent
Re:Incapable of extinguishing? (Score:4, Informative)
Not in the volumes needed to extinguish a burning battery:
As it says, water is not effective if the battery itself is burning.
Airplane fire extinguishers are almost universally halon-based, as halons don't corrode aircraft components, and they work at low concentrations: you can do things like discharge an extingusher into a running engine, or put out a fire in the cockpit without suffocating the pilots.
Here, "copious amounts of water" means the sort of water flow that a pumper truck attached to a hydrant can provide.
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