Light My Fire

December 1, 2011 6:31 AM

iPhones, laptops, the Chevy Volt, and airplanes all have something in common - fires caused by lithium batteries.

Why do lithium batteries pose such a risk compared to other battery types? Metallic lithium is fairly reactive on its own and forms the anode of disposable ("primary") lithium batteries. Secondary, or rechargeable, batteries use a lithium compound as the cathode with an electrolyte that includes lithium salts - no metallic lithium is used, but these compounds are still very flammable. Batteries containing lithium usually fail due to internal short-circuiting caused by external damage - manufacturing defects, overcharging, mishandling, excessive temperatures, or physical shock. The short circuit causes a thermal runaway condition where the exothermic reaction in the battery feeds back on itself to cause more damage.

There has been quite a lot of research lately on the safety of carrying lithium batteries in cargo aircraft after several aircraft have been damaged or destroyed by cargo fires:
-FedEx Flight 0004, Memphis, TN, 2004 (property damage, no damage to the aircraft or injuries)
-UPS Flight 1307, Philadelphia, PA, 2006 (total hull loss, no major injuries)
-UPS Flight 0006, Dubai, UAE, 2010 (complete hull loss and death of both crew members)

Research into aircraft flammability issues have been carried out at the Hughes Technical Center in Atlantic City, NJ. Testing on battery ignition has been performed on primary, secondary, and polymer-based battery cells (all pdfs). The takeaways from this research are that:
-it doesn't take much to ignite lithium batteries
-Halon fire extinguishers, common on commercial aircraft, are ineffective at fighting metallic lithium fires (but it seems to work on lithium-ion batteries)
-because metallic lithium is highly reactive in water, water-based fire extinguishers only make things worse
-exploding batteries create enough pressure differential to potentially destroy Unit Load Devices

Because of the history of fires and the FAA research, the International Air Transport Association has come up with a set of guidelines (pdf) that mostly restrict carrying primary lithium batteries on aircraft as cargo. The NTSB has also issued safety recommendations regarding the use of oxygen masks in the cockpit.

Passenger-carrying flights don't carry batteries as cargo. But what happens when your neighbor's iPhone autoignites on your flight? This FAA video (wmv, 85 MB) shows the effectivity of various methods of extinguishing battery fires in the cabin. Long story short - skip the fire extinguisher, head for the drinks cart. This video (wmv, 204 MB) shows more generally how to fight fires in an airplane, and is geared towards the flight crew.

Happy flying!

posted by backseatpilot (39 comments total)

Thank God gasoline powered vehicles never burn after crashing.
posted by nathancaswell at 6:35 AM on December 1, 2011 [9 favorites]

Here are some "fun facts" I learned from all this (fun because I'm an engineer and failure modes are fun so shut up):

-The batteries in the Volt caught on fire several days after the crash tests. Just because it looks fine now doesn't mean it will be later.
-Batteries have a bunch of safety devices built in to them to prevent these sorts of failures. Notably, there are fuses that are supposed to vent the battery if it builds up too much pressure. However, if the pressure rise happens to quickly they won't work. Also, they have a tendency to spew the (flammable) electrolyte mixture directly in to the fire that's causing the pressure buildup.
-Lithium metal fires are almost impossible to put out. The best course of action is to just let them burn themselves up. Of course, it's a bit difficult to let a fire burn itself out while you're at 30,000 feet because it has a tendency to cause a catastrophic event.
posted by backseatpilot at 6:43 AM on December 1, 2011 [2 favorites]

nathan, the article is very explicit that all involved consider it an uncommon risk unlikely to impact drivers. That a car could catch on fire a week later is surprising, though maybe it shouldn't be. The real question is how much damage you have to do to trigger one of these slow-motion failures and if the internal diagnostics can detect it early. You'd rather not throw away the whole battery / car after a minor impact.
posted by a robot made out of meat at 6:55 AM on December 1, 2011 [1 favorite]

I was just on a flight to the US last month that had to turn back over the Atlantic and land in Ireland due to a very small cabin fire.

The cause?

The wiring for the on-board ovens.

Airline food can kill you.
posted by srboisvert at 7:07 AM on December 1, 2011 [1 favorite]

nathan, the article is very explicit that all involved consider it an uncommon risk unlikely to impact drivers.

The sound bite news outlets won't/don't make that distinction. Wired's headline doesn't even imply the rareness or low risk and impact of the two post crash fires.
posted by Mitheral at 7:17 AM on December 1, 2011

The availability of Lithium Polymer batteries has revolutionized the RC model airplane hobby. Electric powered models are taking over from the gas powered ones that dominated the hobby for decades.

LiPo batteries are safe as long as you treat them nicely. However if they're mistreated badly they turn into nasty little firebombs.

I know of at least one RC pilot who lost his house due to a fire caused by an improperly charged LiPo battery.

When I am charging batteries I always charge them on my brick patio in the backyard where if something went wrong there is nothing that can catch on fire. I never charge LiPo battery packs indoors, with the exception of the little 1s packs that I put in micro models.
posted by smoothvirus at 7:17 AM on December 1, 2011

In one of our classes in college a few years ago we were using LiPo batteries and we needed to put new connectors on each one. We knew you had to make sure you didn't short them accidentally, but the TA snipped both wires at the same time and the wire cutters provided a brief short. The pack heated up and became very swollen. It eventually burst and decompressed, but never caught fire. We instantly understood the quirkiness of LiPo's compared to regular hobby batteries.
posted by Phantomx at 7:36 AM on December 1, 2011

It's fashionable now to brand Bolivia "the next Saudi Arabia". I think they will manage their growth better, however.
posted by Burhanistan at 7:38 AM on December 1, 2011

Only iPhones? What do Android phones use for batteries, alkalines?
posted by entropicamericana at 7:41 AM on December 1, 2011

So... fire bad?
posted by grubi at 7:43 AM on December 1, 2011 [4 favorites]

Something thing to keep in mind about the Chevy Volt incident: A gasoline automobile in the same test would have had it's fuel drained prior to testing. In fact, the car wouldn't even have it's 12 volt battery.
posted by sideshow at 7:43 AM on December 1, 2011 [2 favorites]

Or, its 12 volt battery even.
posted by sideshow at 7:43 AM on December 1, 2011

Thank God gasoline powered vehicles never burn after crashing.

I'm a volunteer firefighter and I've seen hundreds of crashes and very, very few fires as a result of those crashes. The two I've seen in all my years were both single car crashes into large trees at night that resulted in the death of the occupants. There just aren't enough electric/hybrid vehicles in my area yet to get a good idea of how they behave in crashes. I have seen examples of lithium batteries on fire in a truck and let's just say it wasn't a truck any longer once the fire was out.
posted by tommasz at 7:49 AM on December 1, 2011

> Only iPhones? What do Android phones use for batteries, alkalines?

Mine runs on ghee, but you can substitute plain butter in a pinch. Seriously, though. When iPhones are mentioned in these kinds of MSM things it's not because people want to repress and demonize poor Apple, it's because it's a signature and recognizable brand.
posted by Burhanistan at 7:52 AM on December 1, 2011 [3 favorites]

Yes, and it's lazy "journalism."
posted by entropicamericana at 7:56 AM on December 1, 2011

Other possible reasons only Apple gets mentioned:

* Two particular iPhones actually caught on fire.

* Because of the Kindle Fire, it is impossible to determine via Google whether this has ever happened to an Android device.

* Possibly there are more iPhones than high-performance Android phones that use batteries with this kind of energy density, and it's an extraordinarily rare event, so it may well have only happened to iPhones so far? /no idea what I'm talking about on this one

* iPhones are awesome and iPhones bursting with an unquenchable internal flame are just incredibly awesome. This is probably the real reason.
posted by Honorable John at 8:03 AM on December 1, 2011 [6 favorites]

Apple also just had a recall for the first generation iPod nano from 2005-2006 for battery overheating issues.
posted by smackfu at 8:28 AM on December 1, 2011

If you need to charge a lithium polymer battery, you should do it inside a fire retardant bag. "Lipo sack" is what I see is popular.
posted by gen at 8:40 AM on December 1, 2011

Lithium isn't like oil. You can recycle it. It is also pretty common. There are not many mones because it hasnt been very profitable to mine. Bolivia will not have the market control that Saudi has over crude.
posted by humanfont at 8:41 AM on December 1, 2011

My electric scooter has LiON batteries, about 40 Ah worth. If some car driver ever does succeed in their seemingly universal attempts to run me down, you will see me running (or crawling) away from the wreck very quickly.
posted by nomisxid at 8:46 AM on December 1, 2011

Just pulled the battery on my Android phone to check and it says Li-ion on the back. So at least HTC Incredible 2s have this issue, I'd assume that most other Android phones have similar batteries.
posted by octothorpe at 8:52 AM on December 1, 2011

Just pulled the battery on my Android phone to check and it says Li-ion on the back. So at least HTC Incredible 2s have this issue, I'd assume that most other Android phones have similar batteries.

Every cell phone and laptop has a li-ion (or li-ion-polymer) battery in it, because your only alternative is NiMH, which has significantly lower power density.

With the ubiquity of these batteries, it's really only a shock that these incidents don't happen more often.
posted by neckro23 at 9:01 AM on December 1, 2011 [2 favorites]

I know of at least one RC pilot who lost his house due to a fire caused by an improperly charged LiPo battery.

The passive voice really makes that sentence, doesn't it? Let's fix it. You know of at least one RC pilot who burned his house down when he improperly charged a LiPo battery.
posted by The World Famous at 9:17 AM on December 1, 2011 [2 favorites]

It drives me nuts that so many devices with lithium batteries are allowed on planes, while Segways with lithium batteries (which aren't prone to thermal runaway) are not allowed. I believe this is because FAA regulations specify a maximum amount of lithium content, and don't bother with the minutiae of various battery chemistries under the 'lithium ion' umbrella.
posted by hellphish at 9:24 AM on December 1, 2011

Aren't the aisles a little tight for a segway?
posted by smackfu at 9:31 AM on December 1, 2011 [3 favorites]

Aren't the aisles a little tight for a segway?

Like the man in a $3000 suit is going to _walk_ to the airplane lavatory?

COME ON!
posted by running order squabble fest at 9:37 AM on December 1, 2011 [12 favorites]

Just for curiosities sake, could lithium batteries be intentionally rigged to explode, as a sort of higher-tech molotov cocktail/car bomb?

I mean, the potential to act as ignition sources is obvious, but I've never heard of them actually going *boom*.
posted by Orange Pamplemousse at 9:53 AM on December 1, 2011

Add submarines to the list. I was on board for the photo in the article, but not for the fire, thankfully.
posted by ctmf at 10:03 AM on December 1, 2011

Damn, this could really harm the market for electric cars. Who's going to want to be driving around carrying fuel that could just like, burst into flames?
posted by Flashman at 10:22 AM on December 1, 2011 [3 favorites]

I guess the iPhone really is the hot Christmas gift this year.
posted by MikeKD at 11:51 AM on December 1, 2011

The stories mention iPhones because it was iPhones that caught on fire. When I google for android phones or windows phones or blackberries catching on fire, I get more 'iPhone catching on fire' links and that's it. Sometimes the news is just the news and there isn't a conspiracy.
posted by Kwine at 12:12 PM on December 1, 2011

Just for curiosities sake, could lithium batteries be intentionally rigged to explode, as a sort of higher-tech molotov cocktail/car bomb?

I'm imagining a very widely-distributed battery vulnerable to fire at higher drain rates than will ever be encountered in practice because of software failsafes, and then a virus that turns off the failsafes and initiates maximum drain-- one month to the minute after the virus is released into the wild.
posted by jamjam at 1:04 PM on December 1, 2011

Aren't the aisles a little tight for a segway?

I know you're joking, but many disabled people use the Segway as their legs. They should be able to travel too.
posted by hellphish at 4:49 PM on December 1, 2011

I know you're joking, but many disabled people use the Segway as their legs. They should be able to travel too.

I've made a huge mistake.
posted by The World Famous at 5:08 PM on December 1, 2011 [2 favorites]

Only iPhones? What do Android phones use for batteries, alkalines?

Only a mention of Android phones? What do WP7, Symbian, RIM, MeeGo, and other phones use for batteries, steam?
posted by juiceCake at 6:49 PM on December 1, 2011

This is one thing I always think about when I read about promised advances in battery technology-- revolutionary design has 10x the energy density! and all that.

Batteries are supposed to have the highest energy density possible, and they're supposed to be able to deliver it pretty fast. In other words, this sort of thing is almost inevitable, and will probably only become more common and more powerful.
posted by alexei at 6:51 PM on December 1, 2011

I dunno; maybe this is getting a bit Ford Pinto-ish. Oh noes, your treehugging car will turn against you and burn you and the kiddies to death while you sleep!!!!1!! fearfearfear "This would not have happened if you had bought a proper American car that burns Gasoline like God intended, like the Ford F-150."
posted by scruss at 7:56 PM on December 1, 2011

Oh, quite the contrary. Spontaneous car fires are the sort of thing usually reserved for Italian supercars. This is a publicity campaign designed to make your Prius more desirable. Now you can have something in common with a Ferrari owner! Other than both thinking your cars make you better than other people
posted by The World Famous at 8:37 PM on December 1, 2011

I guess I better take things more serious when charging helicopter batteries. Fortunately, my floors are granite, everywhere but the bedrooms. And the concrete-and-steel building isn't going to burn down, either. But no more charging LiOn batteries on the Ikea shelves!
posted by Goofyy at 1:42 AM on December 3, 2011