Flaming Cellphones 288
phorm writes "Many of us have heard the urban legend of cellphones causing fires at the gas pump, but how about the hazards of replacement batteries? Reuters is carrying a story about a woman whose cellphone burst into flame, causing her superficial burn injuries. According to Nokia, the problem has occured before, and is related to non-brand replacement batteries. For various reasons, these batteries may overheat and catch fire, or even explode! So far I haven't found much info on whether this has happened with other brands of phone, though I do know that my little flip-phone gets very hot when running in analog mode. Perhaps some slashdot readers have had a similar experience?"
Other brands of phone - Siemens (Score:5, Informative)
A spokeswoman for Siemens said a GSM (cellphone) of the Siemens brand exploded last year in Germany. It concerned a phone that was placed in a carkit. During recharging, the phone had overheated and exploded. Nobody was injured in that incident. The user of the phone had bought the battery at a fleamarket.
* http://nu.nl/news.jsp?n=193292&c=51 [nu.nl]
Re:My Cellphone is Cool....no really. (Score:4, Informative)
With NiCad batteries, this means several amps of current through a wire mean to handle perhaps
That means heat.
It doesn't mean the cellphone will spontaneously set on fire. It will only happen if the phone is damaged to the point the battery is shorted.
Full power! (Score:5, Informative)
Re:My Cellphone is Cool....no really. (Score:4, Informative)
Lithium Ion batteries and overcurrent protection (Score:5, Informative)
The reason the overcurrent protection is built in is because Lithium Ion batteries will reach the flash temperature of plastic if current is drawn from them too fast.
So... don't rip the plastic off the pack and short them out except by remote control.
Thankyou.
LiIon can easily thermal-runaway (Score:5, Informative)
Lithium Ion batteries will do this very readily when drained or charged too fast...or if overheated past a certain point under what would otherwise be normal current draw...and it's one of the reasons, for example, Panasonic won't sell me the cells I need to fix my Powerbook G3 Lombard's battery(almost all laptop+camcorder batteries, save the newest, are simply AA-sized LiIon cells in various series+parallel configurations).
Panasonic won't sell to anyone except a 'certified systems designer' who has signed agreements saying they'll design proper charging and current/temperature limiting circuitry. God forbid you should simply want to fix a battery pack which is no longer made. I suspect they do it mostly to keep battery pack repair impossible and force everyone to simply run right out and drop $50(cell phones) to $300(some laptop batteries). Sound conspiracy-theory ripe? :-)
LiIon is actually a pretty crappy technology, at least as far as consumers are concerned. Nobody told consumers that for the extra talk minutes they got, their battery will be damn near worthless in a few months if they use their phone a lot...because LiIon looses a staggering amount of its capacity with every charge/discharge cycle- and the deeper the discharge, the more capacity is lost with each cycle. NiMH batteries don't have this problem. Funny thing, eh?
Even worse, the batteries never get recycled(you think the consumer drives to the town dump and puts the battery in the battery recyling box? Nooooooo), they simply get chucked. There are some really nasty chemicals in LiIon batteries(like just about any battery technology today.)
By the way, speaking of batteries and the environment, a lot of people have trouble with car batteries and simply buy new ones instead of taking care of their car battery better(granted, car batteries are usually recycled better, because it's easier, and there's a lot of material, but still...) This site covers just about anything you ever wanted to know about lead-acid batteries and how to properly care for them: http://uuhome.de/william.darden/
Re:Full power! (Score:5, Informative)
Handheld cell phones are limited to somewhere around 0.6 watts. Typically, the newer digital phones (at least from about 3 years ago) would typically have max analog power near 0.5 watts. In digital mode they often can go lower, with CDMA phones transmitting lower still (in theory).
In this case it would appear the phone was dropped. When the phone was turned back on it suddenly ignited. This would seem to indicate a severe short somewhere, and no safety circuit to cut power in case of short, if any such circuits exist on any batteries to begin with.
Typically you hear about two kinds of damage to cell phones. The most common I've heard of is batteries catching fire or exploding during the recharge process. And this is perfectly understandable -- feel a battery while it is getting recharged, they can get pretty warm. Some phone batteries would get so warm while inside the phone on the recharger or plugged into a cig. adapter that they would melt the plastic case of phone itself. I know some "rapid" car cig. adapter chargers from phone vendors have special circuits to control the charging, and the generic cheap adapters don't have the same circuit (if at all).
The other heat related problems I've heard of with cell phones is from extremely long transmissions. Say a handheld phone plugged into a cig adapter and used for 200+ minutes. The transmitter can get pretty warm, and I've heard of some of the smaller/thinner plastic phones (early MicroTAC? don't remember for sure) had plastic melt.
I've never heard of a phone bursting into flames, melting the case, or otherwise get hot when it was not directly related to recharging or extended use. At least not until now.
Something had to be pretty severely damaged or there was no safety cut off circuit somewhere to allow a cold phone to burst into flames like that. Sometimes those bargain batteries and accessories aren't such a bargain after all.
Here's my question. Did she get the battery used in this phone from the same store she got her phone from? I've bought several phones over the years, and the last few years you just about could not find OEM parts, the carrier stores had the cheap stuff there in packaging with their carrier names on it. So, if she bought her phone from a carrier store, and they gave her the battery, then would that carrier assume the liability for this happening, since it was not a Nokia battery involved?
Re:Other brands of phone - Siemens (Score:5, Informative)
Heise has had an article [heise.de] on this as well. Translation follows.
Normally, one would only see this kind of stuff happening in rather bad secret agent movies, but now it happened to a woman in Amsterdam: Her cell phone exploded. These news about the exploded mobile phone are likely to disturb many cell phone owners: "Could this happen with my phone too?" In the Netherlands city, the woman's phone had first fallen to the ground. When she turned it on again and held it to her ear, the device exploded and caught fire. The woman suffered minor injuries. Experts, however, see no reason to be concerned: Cell phones explode extremely rarely, according to Bernd Schwencke, head of the cellular phone testing department of the German Quality Testing agency, Stiftung Warentest, in Berlin.
"Up to now, no such case was known to me," Schwencke notes. According to him, what's unusual about this event in the Netherlands is that the phone did not catch fire during recharging as in previously known cases, but while using the phone. In previous cases where the rare case of a mobile phone catching fire occured, forged batteries were spotted as the cause. This was also the cause when a Siemens phone caught fire during recharging in a car kit. The phone manufacturer was not responsible -- the device was equipped with a bogus battery that was not properly working. "The accumulator had no overcharging protection and simply burst like a balloon filled with too much air," says Stefan Muller, spokesperson for the Siemens mobile phone division in Munich. Unfortunately, the plagiarized products mostly originating from Asia are still a problem, according to Muller. To prevent the use of such "time bombs" in cell phones, the experts advise to only buy batteries in specialized stores instead of flea markets -- even if a manufacturer's logo is on the battery.
Re:Nokia says... (Score:1, Informative)
Norway, November 2002 (3310 exploded in classroom)
Belgium, January 2003 (3310 exploded at home)
No injuries in both cases.
http://www.gva.be/dossiers/-g/gsm/binnen22.asp
Is There Any Way... (Score:4, Informative)
I do commercial radio repairs for a living so I may have a little insight here.
First, let me say that the heat generated by the phones while transmitting in analog mode is due to heat generated by the RF power amplifier IC Module in the phone. It is the most power-consuming part of the phone, followed by battery recharging and backlight hi-voltage power supplies. Hand held cell handsets are usually power limited to 300 mW max. The old Motorola Shoe Phones used to put out 3W of power max. (!) before the cell tower infrastructure was sufficiently built up to not need those levels of power.
But anyway, the battery only gets hot while charging. If it gets hot during discharge, it's under a serious over-current situation that is a "Bad Thing" and would never be designed as such. The only situation like that I've ever heard of is with some R/C racing cars that have special hi-temperature battery packs that are specifically designed to deliver high current into a near-short circuit condition. And they don't last very long in that sort of service!
Finally, about the urban legend - there actually may be something to it. I know that Motorola Handie-Talkies are sold in what the call "Intrinsically Safe" versions, that are for use in mines, and explosive atmospheres (chemical spills, fires, etc.)
All of the contacts and switches inside the radio are not hermetically sealed, and even the tiny arcs they make at 5-7 volts are enough to detonate an explosive atmosphere. So they make the radios with something like a tire valve at the bottom, and positively pressurize the radio to +1 atmosphere with nitrogen. These radios and their batteries are marked with green dots, and have an MSA (Mine Safety Associates) approval sticker on them.
To the extent that gas fumes are explosive in the air while refueling a vehicle, if the radio isn't an intrinsically safe one, the possibilty of detonation exists. Probably it would only happen from switch contact closure, if you were talking and not dialing or opening/closing the phone by the pump, then nothing would be likely to happen.
dell laptop batteries have done the same thing (Score:2, Informative)
U.S. Navy (Score:3, Informative)
Um, no. (Score:3, Informative)
-Mark
Gas Pump - Drop phone - spark - boom - (Score:2, Informative)
It can happen (Score:2, Informative)
Re:Gas stations and lithium ... (Score:2, Informative)
I know of lithium batteries, and yes they have been around for cameras, etc. since the 70's.
As for the self-discharge, I think _you're_ confused - you must be thinking of Nickel Metal Hydride (NiMH) batteries, which self-discharge up to 10% per day. Li-ion is more like 5% the 1st day, then 1-2% per day thereafter. I think the spec you are mis-quoting is a self-discharge of 10% _per month_ with Li-Ion.
Finally, any self-discharge is irrelevant. The rechargeable lamps and radios they carry are sitting in rapid charging adapters in their tents or tanks until they are pulled for use (like police radios) and are thus always "topped off".
Not only that, but the energy density of the Li-Ion cells allows for the batteries to be made with more overall power capacity (by whatever factor is desired) to compensate for any possible increased losses.
Physics of Shorted Batteries. (Score:4, Informative)
The mechanism for the exploding cell-phone batteries is most likely the same mechanism for exploding car batteries. Namely, electricity can cause the oxygen and hydrogen in water to dissociate. When this happens, if they hydrogen and oxygen mixture cannot escape, the pressure and the stored energy in the gases builds up. Eventually, there is a spark, or a pop (and then maybe a spark) which causes the battery to explode and then the hydrogen/oxygen mixture burns.
I think you're overcomplicating things.
Take a piece of wire. Wrap it in plastic. Use it to short out a freshly-charged Ni-Cd, NiMH, lead-acid or Li-ion battery. Flames.
Any power source - battery, power supply, whatever - capable of good current can heat a piece of wire enough to cause ignition. Think of the wires in your toaster.
This is not like the old carbon-zinc Eveready "cat of 9 lives" batteries you'd short out when you were a kid. These actually have lots of stored energy and very little internal resistance to limit the short circuit current.
The problem now is that modern battery technology which gives us long cellphone and PDA charge times also means that we're carrying around a lot of chemical energy in our pockets, and any failure which results in a short circuit across the batteries will generate a lot of heat and potentially ignite plastic housings.
Never mind that as you increase the energy density of a battery, you must - by the very nature of electrochemical cells - be increasing the reactiveness (ie. toxicity and danger) of the chemicals used to make the battery.
If you think this is fun, just wait until we have electric cars! Think gasoline is nasty stuff? (I can't wait to say, "I told you so!".)
Bad design hits wallet too... (Score:2, Informative)
But do you think they put millions into battery design? Maybe they should...
Interestingly the documents p.23 of 35 in pdf [dell.com] seem to show Dell shelling out a $30 coupon to each owner of the flaming laptop batteries and more to the flaming lawyers... Perhaps this explains Panasonic's reluctance to sell dangerous batteries to "just anyone"...
Ni MH Batteries also overheat whilst charging. (Score:2, Informative)
When NiMH batteries first apeared we who used them commercially had to purchase all new chargers for them. The batteries have a nasty habit of overheating whilst charging, the chargers have a built in thermistor system to cut off the charging current if this occures.
As someone pointed out in an earlier post, if aftermarket manufacturers want to save a few cents then............