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Warning: Exploding Batteries
batlike writes "It seems I have been quite lucky up to this point as I habitually leave my laptop in the trunk of my car - which is just over the gas tank (duh!) . See this article in InfoWorld by Ephraim Schwartz for details. You may want to give it a once over if you currently use lithium-ion batteries."
Of course they don't really explode into a fire ball but rather short circuit, heat up, melt, and leak acid everywhere.
There is or can be built a machine that can simulate any physical object. -Church-Turing principle
My laptop gets left countless places unattended, many of them could get quite quite hot if the air conditioning quits. So what can you use as a safety? (Other than removing the battery).
So if you buy something where you can't change the battery, expect a finite life out of it!
It's not wasting time, I'm educating myself.
Article was not much more than an advertisement for Valence and their new Battery Technology.
(sigh)Lucky for us they didn't require us to pay for that crap.
Visit CryptoGnome in his home.
I don't know why the worst of these, the Prismatic lithium ion polymer battery, isn't banned. There's so much packed into them that a slight overcharge can lead DIRECTLY to thermal runaway, and they're becoming more and more popular in laptops. What's worse?
The battery's charging system is under the control of firmware. One dodgy firmware update and you could have a battery on your lap, in your home, on your desk, in your car, suddenly "expire with flame". a subtle way of saying "spray red hot lithium metal all over your legs and genitalia".
I smell a large, very expensive class action for all manufacturers using these, and unfortunately not until many, many more people are injured or killed.
Did they pay the author to 'brand-build' at the end of that article? NEC Corp has done and is doing more to advance battery tech in terms of both innovation and safety than either of those two combined. I guess they count as the "others"?
It seems I have been quite lucky up to this point as I habitually leave my laptop in the trunk of my car - which is just over the gas tank (duh!) .
;)
You may want to give it a once over if you currently use lithium-ion batteries."
Considering that I usually keep my laptop in my trunk, i can rest knowing that I can pull it out and replace it with some safer items like a gasoline canister, some fireworks, my blowtorch and some booze (it is new years eve, after all
Join the TWIT army now!
Considering the number of people that use these batteries and number of people that overcharge, I don't see a trend at all, just people that don't know how to use a device properly
so i go to read the story and...
"Because Valence claims to offer a safer alternative"
"Currently, Valence is shipping outboard devices -- N-Charge, weighing just under three pounds"
"The next generation from Valence will be small enough to use as a direct replacement for your current laptop battery and will be available next year."
come on slashdot, infoworld, this isn't news, this is a PRESS RELEASE
replacing it with NEW Folger's Crystals! (lets see if they notice the difference)
The article didnt give any particulary useful information, just stating the obvious. It was nothing more than a small plug for the new types of batteries that are due to be launched. And anyway, it's common sense not to leave batteries unattended in hot conditions, etc. Argh, but saying that, my NEC laptop's battery does get extremely hot during use, usually by conducted heat from the whole laptop. So did my old vaios' too.
Well, any kind of high energy battary poses a kind of danger. The energy density of modern batteries approaches that of nuclear reactors. Any kind of physical damange (also heat) may release the stored energy in a quick fashion. Naturally it will be converted to enormous amounts of heat..
and are a "tiget in a cage." His company is marketing a competitor to Lithium-Ion!
Well, it's the middle of winter here and even my flat is cold, so no danger here!
I mean, who leaves a laptop in the trunk?
Or are you just going to sit there spewing Digital fanboy ejaculations?
But when I read three stories, all in reputable news outlets, well, that's a trend.
Okay, chicken little. Whatever you say. Three stories in reputable news outlets is a trend. Let's see. If .05% of the 290M+ population of the U.S. owns a laptop, that means what, 2.06 x 10^-6 % of all the notebook owners in the U.S. experienced that in the past several months (someone might want to check my math.. it's really early)? That's a trend? If that's the case, aren't you far more likely to win the lottery several times than have your laptop battery explode?
Imbecile. There's an enormous difference between something being a possibility and being even remotely likely. Sounds like those idiotic news reports networks show to get stupid people to watch ("WILL YELLOW STICKY NOTES KILL YOU? FIND OUT HOW YOU CAN PROTECT YOU AND YOUR FAMILY AT SIX!!!!")
Alito: A vote for Alito is a punch in the eye to put that bitch back in her place!
They're "venting with flame". (Kudos for the link to the site go to Steve Cowan)
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
So if you buy something with a battery, expect that you will get a finite life about it, and think about how or where you will get a replacement before you buy the product.
T Money
World Domination with a plastic spoon since 1984
when I read three stories, all in reputable news outlets, well, that's a trend.
This reminds me of the shark attack reputable news outlets suffered a few years ago. Nothing much was happening, so they covered the ongoing tragedy of swimmers who are attacked by sharks. Yes, this may happen but I'm no more worried about my cell phone or laptop exploding than I am about being eaten by a shark.
Friends don't help friends install M$ junk.
Don't you mean power density (watts per cubic inch)? I would love to have a battery with the energy density of a nuclear reactor.
Of course Batteries have not doubled in capacity every year, but that doesn't mean that thier growth and development is coming to an end. At the end of this article the author claims that in 5 years we will not longer be able to improve on batteries. Though we may not be able to improve capacity or discharge, which I still feel is underestimating our ingeniouity, we will be able to further improve on batteries by finding new sources, find new ways of recycling batteries, or making batteries last longer(in lifetime).
There is or can be built a machine that can simulate any physical object. -Church-Turing principle
More worried about losing his car than his laptop exploding and taking his manhood... sheesh.
"When you heat this material up, it [can] reach an onset temperature that begins to self-heat and progresses into fire and explosion."
You really can't go replacing important words like that. Who knows if the word "can" was to replace something like "has the small possibility to" or "can under extreme and rare conditions"...
Filling in the blank with the word "can" has the possibility of throwing the perspective out of proportion. Even later in the article it states that "explosions and fire happen 'rarely'".
And what really got me...
Long-term fuel cells that convert hydrogen and oxygen to electricity -- don't ask me how -- are a promising alternative.
So replace lithium ion batteries with a HIGHLY combustable mixture... good alternative...
NEC Corp has done and is doing more to advance battery tech in terms of both innovation and safety
You missed his point entirely. He mention the two semicon manufacturers as a way of pointing out that the "best" solution may be to make devices use less power, vs getting more power/life out of batteries. I disagree as some "power hungry" folk will always need more oomph from their systems and therefore their batteries, and having the cpu sleep to count on getting better life isn't always a viable alternative.
This should come as no surprise to anyone that's ever used a laptop that got "hot". The first time I put a "hot" laptop on my lap, I freaked out at how hot it actually was. I can't believe that more laptops don't just melt from their own heat anyways, much less the battery exploding, catching fire, or whatever's "really" happening here.
stuff |
At least you knew where you were with good old coal...
"is it on yet?"
"yup!"
Isn't this akin to reporting the dangers of using a hairdryer while showering?
Wasn't this the cause of all the PowerBook 5300's catching fire and exploding back in '95 when they came out? Or perhaps that was just a charging issue.... I must agree though that article was very clever in its promotion of the Valance Saphion technology.....Bringing in quotes but no actual numbers(probability) of current batteries actually exploding... I know my iBook battery sure gets toasty, heck the whole laptop and charging unit warm up to well over 100F. But I've never heard of a iBook battery(Lithium ion) exploding.....Maybe they're talking about operating these things inside a furnace, or perhaps on Mercury, or even the face of the sun....
-sonic
...not the trunk. Don't believe me? Stick yer head under the car and follow the fuel fill pipe. Tell me where it goes. ;-)
If you you were in the U.S. Army sometime before 1990, you probably know what that means. These were the standard field radios before the new SINCGARS encrypted/frequency-hopping radios came into use. The old "prick 77" radios that we carried around on our backs used a lithium battery. The radio had a vent on the battery compartment to let out explosive gases (and water if you were dumb enough to get your radio wet). If the vent became blocked the battery could explode! Ouch! Never happened to me personally, but it was legendary among RATELOs.
But I don't watch a lot of TV news... maybe I've missed these stories:
The UK TV show Brainiac put the whole cellphone-at-a-gas-station theory to the test - they doused the innards of a caravan with petrol, and chucked a load of different mobiles in there all over the place. They then rang the mobiles to see what would happen.
Nothing happened.
So, they ran a wire to the caravan from a big bucket
Some loony dressed in some nylon clothes, stood in the bucket, 'rubbed himself', then touched the wire.
Boom.
Why don't we see "no dancing nylon loonies" signs at petrol stations?
You'll want to add some firearms and ammunition to your party supplies.
Guns, cars, and booze are an American holiday tradition, although I must admit that the Arabs and their AK-47 tributes are pretty impressive. Except don't a few dozen people die every time there's a big hoopla involving firing AKs into the air?
Automotive batteries can vent explosive gases too.
That's why the experts have you make a "jumper cable circuit" by attaching the last ground connection away from the battery. In theory, the spark could ignite gases venting from the battery, resulting in an explosion.
I've never experienced such an explosion.
Most AC adapters max out at something like 400 mW. They'll shut off if they're asked for any more than that. Most laptop ones will only give out 2 or 3 amps at 18 V or a max of 54 W. Not 1.8kW, but pretty scary nonetheless.
-Your friendly neighborhood EE
The previous sig has been removed due to
I habitually leave my laptop in the trunk of my car - which is just over the gas tank (duh!) .
Sir, I don't know the make of your laptop, but I'm pretty sure that if you'll read the user's manual that came with it, you'll find a passage like "do not leave it in locations where the temperature can become unpredictable or extreme - like a car trunk". Such a passage is in mine. I'd say that your horror story boils down do "if you habitually neglect the recommendations of your user's manual, bad things can happen".
LiIon manufacturers know what they're working with and so do their customers. There is nothing about a prismatic cell that makes it inherently a timebomb waiting to burn your genitals. Cell size is limited on the open market. Larger batteries are co-developed between cell manufacturers and their customers to insure safety.
Engineers are well aware of the need to charge the cells carefully. That's not an inherently dangerous task either. Firmware that controls charging circuits runs on a dedicated processor, not the main system processor. It's highly unlikely that a firmware update would cause a charging problem since that portion of the firmware will likely be unchanged throughout a product's shipping lifecycle. A company would be seriously negligent to allow a bug of that nature to slip though to the customer. Companies are quite sensitive to having their products explode in the field.
maybe he has a pickup?
Comment was not much more than an advertisement for CryptoGnome and his website.
Seriousy, though, I got a $50 CompUSA gift card from my in-laws for xmas, and yesterday blew it all on rechargeable batteries (NiMH) and a charger. It's my first set of rechargeables since the 80s, so I did a lot of reading about batteries over the weekend. One of the most interesting things I read was that Li-ion cells have a non-insignificant percentage of the power of dynamite.
At first I thought I'd be getting some high-tech toy with the gift card, but the rechargeable batteries idea grew on me and just made so much sense- economically and ecologically. And in one of those odd coincidences, when my wife came home last night, she said she was wondering on her drive home what MP3 players/digicams/cell phones would be powered with 5-10 years from now. I told her I thought fuel cells would be advanced enough to be widespread by then, and by that time the rechargeable batteries I'd just bought would be at the end of their useful lifespan.
pax,
fred
One way to avoid problems is to only buy batteries that have been tested and approved by the device's manufacturer. Many of the reported problems with catastrophic battery failure can be traced back to no-name or counterfeit batteries that are missing crucial protective circuits and features.
Mea navis aericumbens anguillis abundat
and McDonald's coffee
So that's how the terrorists do it...
the article is a blatant advertisement. nice one though.
When is Slashdot going to start allowing us to mod entire stories down ??
Ok. Those batteries you have there are unsafe. They could catch on fire or even explode!
Fear not, I have the solution.
Buy my safe batteries, free of pesky thermal runaway, free of fire, and annoying explosions.
I was using a rather ancient Thinkpad (P233 - excellent screen and keyboard though!) whose battery life had progressively gotten worse. Once I was sitting there using it and the laptop went POP! I ripped out the battery as fast as I could. I didn't see any external leakage, so I just threw the battery away (oops, I know that's bad) and continue to use the computer sans battery.
...is not found in its energy density. I doubt that's what you mean, either.
Energy density is not solely responsible for the explosion risk of LiIon either.
The rate at which fuel cells react is limited. Fuel cells do not contain "a HIGHLY combustable mixture".
defibrillator
Lithium primary batteries are not the same as LiIon rechargables. They can be a serious explosion risk though. PC's contained them for many years, and the PC ones would explode if you wired them backwards. In many cases the connectors of these batteries were not polarized either. This problem has nothing to do with the topic at hand.
This is old news lithium-ion batteries require special chargers and cannot be charged at a high rate. You also cannot discharge them quickly. the first people to attempt to use them in electric rc airplanes found this out.
You can't, it's often integral to the cell, so a fair amount of surgery is involved.
Nearly perfect bomb and perfectly legal to bring onboard passing all security checks with flying colours.
Oh for chrissakes...no, something that would get really hot, start smoking, and then catch fire. Ever since(and in fact before) the Valuejet incident, planes have smoke detectors and fire suppression systems in their cargo holds, so it's a moot point if it ends up in cargo vs. carry-on. The issue of toxicity is moot because that's why planes have oxygen systems that the pilot can deploy. The mask systems in the cockpits are also usually much better than the paper-cup jobbies the Cattle get.
People- Calm. The. Fuck. Down. Planes don't explode because something inside them catches fire, they don't start crashing because someone shoots a gun, yadda yadda. Cars don't explode because a battery overheats in the trunk. Stop watching so many action movies...
Please help metamoderate.
Mmmm, fizzy.
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
The original model didn't have a vent. Explosive gases would accumulate until a spark caused an explosion. They added the vent after a number of people were seriously injured.
Mea navis aericumbens anguillis abundat
I often read about how much "Bang-for-the-Buck" that you get from CPUs, Video cards, etc. I think that this might lead to a new system for rating laptops!
If "disco" means "I learn" in Latin, does "discothèque" mean "I learn technology"?
You just plain can change the battery on the iPod. $99 and Apple will do it for you. $59 to do it yourself. Obviously on Apple's laptops you can also change the battery. So the "hear this, Apple" line implies something totally untrue.
full report (source of the referenced voltaic page) is at the cdc site, http://www.cdc.gov/niosh/face9939.html
[this sig has been trunca
In the USA, 3 stories is grounds for a class action suit.
Clear, Dark Skies
From this article:
Macworld : More PowerBook 5300 woes: battery, power, and circuitry flaws. (Product Support) : Lu, Cary
More than any previous PowerBooks, Apple's most recent high-end model has been plagued with a host of troubles. First, Apple replaced the lithium-ion (LiIon) batteries it had begun to ship with 5300-series PowerBooks (see News, December 1995) because two of the Sony-made batteries had caught fire. Now , ironically , Sony's LiIon battery-producing plant in Koriyama , Japan , has itself been destroyed by fire. The Koriyama facility produced 3 million LiIon batteries a month (about three-quarters of the world's supply) , and Sony's second LiIon plant , in Tochigi , Japan , won't be operational until the spring. Thus , even if Sony figures out what went wrong with the LiIon batteries , no new ones will be available until at least mid-year. So Apple will have no choice but to continue shipping 5300-series PowerBooks with nickel-metal- hydride (NIMH) batteries , which it began doing when it resumed PowerBook shipments.
Funny how certain stories will catch fire (ahem) every once in a while. If only sharks were to catch brain tumors after having used cell phones habitually, then we'd have a "trend" on our hands. Whoo-boy.
And the trend would be "People develop irrational fears over stuff they don't understand, and once they're in the grip of fear they'll perpetuate it instead of even trying to understand..." Welcome to my Southern Baptist relations' world view.
Incidentally, bull sharks do tend to be involved in more attacks every several years. Something will change about where and when they're mating, apparently. That's when the attacks tend to occur. They're the only big shark that heads into shallow, briny- (or even fresh-)water areas to mate, and people aren't used to watching out for them. The famous New Jersey attacks that inspired Jaws were an example of that. Our big shark stories from a while back didn't even bother telling us that, though. And you're right, the number of attacks that year wasn't particularly high. Sharks just caught the news industry's fancy.
In this case it's just the usual PR release that some lazy reporters and editors passed on to the public. If the shark stories had been shilling repellent devices, that'd be comparable. Personally my elephant repellent business hasn't been doing so well; I'm thinking of writing a press release.
"Fundamentalism" isn't about divine morality. It's about human authority.
This story was posted here a couple of years ago, I think it was IBM laptops that were exploding. In the end they tracked it down to the users all using cheaper clone batteries. Serves them right.
Powerbook explose
It's a good thing the Toyota Hybred car does not use these batteries. A 100+ Lb battery pack would not be fun to have melt down in the trunk.
FYI they use Ni-Metal Hydride batteries.
The truth shall set you free!
When the huge torrent of Mad Cow news hit CNN all day yesterday, I went to look up some statistics on deaths in the US. - 700,000 people die of heart disease every year - 43,000 people die in car wrecks - 28,000 die by firearms - 553,000 people die of cancer - 0 people have died of Mad Cow in the US - 774 people have died of SARS globally - 143 people have ever died of Mad Cow in the US - There have been no reported deaths of exploding batteries. Statistics are mostly 2002 taken from the National Center for Health Statistics. http://www.cdc.gov/nchs/fastats/default.htm Keep the cell phone and laptop and use them however you want. Put the bacon cheeseburger down instead.
Mike Shea
mike@mikeshea.net
http://mikeshea.net/about/
Colson-Inam advises users not to leave a laptop or cell phone in the trunk of a car
My insurance only covers theft if the objects are stolen from the trunk of my car. So I guess I should always take my notebook with me when I leave the car since I can't place it in the trunk.
Not that I want to take a risk of my laptop blowing up, but a replacement battery for a laptop like my Thinkpad is :
;-)
That's a lot to pay every 2 years to prevent a fire no?
I'll most likely still do it, but that hurts. Now when do fuel cell batteries come and save my day? I wouldn't mind popping one of those wonders in this clunky power eating thinkpad.
PS: I need a G4 powerbook! That would be sweet
This is the required post reiterating that honorable Senator Jake Garn approves of any and all technologies that involves exploding computers. As for the exploding laptop causing a car to explode, causing a gas station to explode and causing a small city to burn to the ground...this is a good reason why you should buy a monster truck...as there is nothing more exciting than an exploding monster truck.
The video campaign may not have influenced Apple to lower their outrageous $255 fee to $100 (plus shipping) but I'll bet a lot of irate customers swearing at hapless Apple tech support reps did. I'll bet the calls got even hotter when the reps suggested just buying a new iPod instead of forking over the $255.
What Apple has done for those early customers?
Jeez, this guy writes like someone in Ann Coulter's Baby Gestapo or something.
Hmmm... or more accurately, many manufacturers would like you to believe that the less expensive batteries sold by other companies are somehow hazardous to your health.
Sure I'm not going to buy a battery from a guy on a street corner, but neither do I believe that an aftermarket item is necessarily inferior to the manufacturer's version. Often they come out of the same factory.
Three Squirrels
This run-away reaction they're warning us about starts at 140F... that's pretty warm to the touch, and if your devices get that warm when you're using or charging them, you really should contemplate the safety engineering of the device in question. e.g. I have a Siemens cell phone with a li-ion battery, and it *never* gets warm, even if I run the battery down from a full charge to completely flat (over two hours on the phone). My girlfriend's Samsung phone, also using a li-ion battery, is warm to the touch after 5 minutes of talk time. If the gas tank on one (or more) manufacturers cars reached ignition temperature during operation, would we blame the characteristics of gasoline for the fires? Caveat Emptor.
No, a better measure of the energy the battery is capable of storing is the mAh rating. If the battery says it's rated for 1000mAh, it can supply 1000mA for 1 hour, or 500mA for 2 hours, or 10mA for 100 hours. etc.
Note that you simply cannot look at the wattage (power) available from the battery, since power is a measure of work over time. And besides, you want to know what the total energy stored in a given battery is, since that's the total energy available for release in a catastrophic failure (ie, how hot will your kids' asses get when the wires between the motor and backseat Li-ion battery of your Civic Hybrid are frayed and shorted in an accident?)
So, how many joules of evergy are in that 1700mAh AA Ni-MH battery?
Well, work = power / time, where time is in seconds, power is in watts, and work (energy, potential or kinetic) is in joules. 1 hour has 3600 seconds. Therefore, 1700mAh = (1700*3600)mAs = 6,120,000mAs. Yeah, your lowly little AA rechargable would happily dump 6,120A in 1 second if the short circuit had small enough resistance.
Now, since we're going to employ a cancellation trick here, that work from the battery, for one second, is (6,120As * 1.2V) = (7,344 watts)*1s. Note again that this is 7,344 watts for one second. Note also that since work = power / time and time is taken to be one second, work = (7,344 watts * 1 s) / (1 s). We can now cancel time units and the division is effectively done, so the answer is expressed in joules: 7,344 joules.
7.3kJ released in my pocket if the battery fails catastrophically? No thank you.
I'd love to know the Ah specification for the battery in the back seat of the Honda Hybrids. It absolutely terrifies me to know that idiots are buying them and driving around.
(I love electricity enough to study it for four years of university hell. I say this, therefore, with some educational basis and reluctance at knocking my favorite energy: electric/hybrid cars are stupid. The batteries are time bombs, hazardous waste and chemical burn nightmares. The charging process is inefficient at best (<50%). How many new coal and nuclear power plants are gonna have to be built when 10,000,000 Los Angeles commuters start plugging in their electric cars every night?)
Fire and Meat. Yummy.
Yeah, um, wasn't this the whole deal with the Ford Pinto? The gas tank was under the trunk, and it kept exploding whenever rear-ended. Hell, everyone knows about the Pinto, except seemingly the submitter. I realize the issues weren't *solely* due to the trunk-mounted tank, but this is almost the most famous automotive design issue in history.
:)
If you're going to believe chicken little stories about batteries that there are a whole 3 (!!!!!!!!) cases of explosion listed, and drive a car with the gas tank under the trunk, you're either really young, or just really stupid
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
Here's my munged link:
http://www.fordpinto.com/blowup.htm
Preview, damnit, preview next time!
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
Upon visiting Sony's support site recently, they had an alert out for just this sort of problem - but they claimed that it would only happen with third-party batteries, not the much more expensive Sony certified batteries. FUD, or is there a real difference between the two types that makes the third-party batteries more dangerous?
--- Bwah?
I agree with most of your sentiments, except one. The gun one. Would you be willing to sitting in the window seat, as a gun gets fired into the body of the aircraft right next to you, while the plane is between JFK and CDG?
I think it would be very cold and windy...
I'd worry more about the bullet going through a fuselage skin. The puncture shouldn't tear, but shit does happen. (Remember Aloha Airlines Flight 243 and the ill-fated DeHavilland Comet...)
Fire and Meat. Yummy.
This isn't anything new, I've known about this danger since the advent of Li Ion batterys. This is why they require a special charger, normal charging methods used on NiCad and NiMH would cause them to explode.
Don't forget that when Motorola released their Micro-Tac Elite (then the world's smallest and lightest thanks to it's Li Ion battery) cellular phone, that they had to switch to NiMH batterys for a while shortly after they went on sale because the only battery plant producing Li Ion cells at the time blew up!
Remember the Flaming Pop Tarts of Doom? How about the "Roller Blade Barbie", Pampers and hair spray experiment?
When Dave "Mr. Average Consumer" Barry takes a few Li-ion batteries, a bottle of Everclear and a hatchet out to his driveway for a controlled test, that's when we'll know the threat is real.So will his neighbors.
You were 80% angel, 10% demon. The rest was hard to explain. - Over The Rhine
"Math in a song is good."-Linford
I wish it were toxic, my ex takes it...
These don't seem to have the problem of fuel cells and would be difficult to make explode.
0 0, 00.html
http://www.wired.com/news/technology/0,1282,484
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
No, wait! I don't really want to know, do I?
I'd rather you do it wrong, than for me to have to do it at all.
if there were a SINGLE event of "explosion" it would be big news. shades of cell phone gas station scare.
I now have the sudden urge to go and buy a crap-load of laptop batteries.
Is this a good thing?
-[EPSILON]-
There's no way one of today's AA batteries could deliver that kind of amperage, even for a second. All cells have some internal resistance which limits the current they're capable of delivering, even under a "short circuit."
Now the battries used in an electric/hybrid vehicle can supply quite a bit of amperage, but are still limited by their own internal resistance.
In short, no cell can possibly deliver all it's stored energy in a single second.
True, shit does happen. But I think my immediate worry would be getting accidentaly shot rather than a series of failures leading from a hole that's maybe the size of my thumb (that's assuming a big handgun), to me and my chair getting sucked out of the plane. A hole in me is much more likely to lead to fatality than a hole in the plane.
If you leave anything in a car in Florida in the middle of summer it's likely to either melt, explode or both. In the case of a laptop, melt, that battery will rupture or some kid'll steal it :-)
This is just a crappy P&R feed for this guy's "new and revolutionary" process.
As a matter of fact, yes, the cell itself can explode, if you try really hard and heat it a lot (much more than 140F). Modern cells in a reasonable ambient temperature will not ignite even when shorted (I was really disappointed when I tried that with Sony and Molicell elements, no fireworks for me).
However, all consumer battery packs have substantial electronics in between the cells themselves and the pack terminals. All of them have mosfet switches that turn off when they detect a shortcircuit (or merely an overcurrent) or if the charger goes crazy and tries to overcharge the cells or if the cells' temperature exceeds a certain value - typical 55*C for charging and 60*C for discharging.
They also have a one-time fuse "detonated" by a separate chip that senses when the cells are about to go. From this p.o.v. there are two or 3 levels of redundant protection in every LiIon/LiPoly pack sold.
The chargers also are specially designed for each kind of battery pack. They are I/V limited chargers, with the I dictated by the current rating of the cell (a 4000mAh pack is charged with 3 to 5A) and the V determined by the cell configuration: one cell (like in cellphones) needs 4.2V, three-cells (the 10.8V packs) need 3*4.2V and so on.
There are also extensive (fanatic actually) reliability tests done when qualifying the packs. Paper clip shorting, ESD zapping, puncturing, submersing, everything is tried. There is a rigorous TUV standard for these tests - look for the TUV logo on your pack and you'll know it passed the test.
I believe that you can explode a LiIon cell only if you throw it directly in the fire. But an equally bad BOOM! happens if you throw in the fire a pressurized aluminium can and nobody goes crazy when handling a RAID cockroach spray.
Serban
some cheap third party batteries leave out short circuit prevention circuitry. If you short one of these batteries out and it doesnt have that circuitry, it will rapidly overheat and likely blow.
There could be other risks involved with different chemical formulas as well. Recall the blown capacitor debacle a year ago or so where the one cheap taiwanese company left out the ingredients to make the electrolyte in capacitors not create hydrogen gas. Gas build-ups blew out capacitors on many devices and motherboards (including a Soltek I owned at the time).
-
I've opened all the side panels and bottom panels and none of them leads to a hard drive. As best I can tell, the hard drive is near the front of the laptop under the touchpad, but I haven't been able to access it yet, even after unscrewing all the screws on the case and opening the laptop as far as I dared.
If you know how to replace the hard drive on a compaq presario 2100us, I'd love to hear from you.
As for the question of whether to leave the battery in, I usually take it out for long term storage because the buchmann battery faq says li-ion batteries store best at 40% charge level and cold temperatures. While I don't go so far as to refrigerate my batteries, I can't help but think that storing them at 40% charge, 25 degC is better than storing them in my laptop where they would be at 100% charge, 40 degC. So far my oldest battery (1 year old) is at about 88% of original charge, which is in line with the figures given on the web page considering that it has seen more usage than just sitting in storage.
I had a deep cycle RV battery explode while charging. Sounded like a shotgun blast, set off the alarm on my car located 50 feet and around the corner from the blast, and brought several neighbors out into the streets.
Incidentally, this was the same day I received a summary judgement against a shady character who ran me off the road a month earlier. When I heard the blast and my car alarm went off, my first thought was that he was out there with a shotgun finishing my car off.
-Ryan, with the unoriginal sig
I have. I was standing outside about 30 feet from a friend's car when he started it and the battery exploded. There was acid all over the inside of the engine compartment and I saw a very small amount of flame escape from under the hood. The top was blown off the battery, and he replaced the battery and drove on his merry way. I hosed off the driveway to dilute the acid so it didn't kill all the grass along my driveway.
For an explosion (or "venting with flame") is was relatively uninteresting.
Learn to love Alaska
...then I better start calling my Nomad "No Nads" since it usually rests oh-so nicely in my lap.
Silly e-Death.
An old roommate of mine was president of the KSU solar car team. He was telling me how the batteries are among the heaviest components of the car. Lithium ion i think they use now, but the had to have a student spend his Masters work on building a power management system so that the batteries charged without exploding.
Apparently the result of a battery explosion is a large cloud of gaseous material. Supposedly not very flammable but extremely reactive with things like car materials and people. Battery technology hasn't really moved a whole ton in the consumer market lately, but there are a few interesting new ideas. One involves a wrapped cylindrical design, sort of like a fruit rollup, if you were a child of the 80s. Not sure about the benefits outside of a lighter battery, though.
I Browse at +4 Flamebait
Open Source Sysadmin
"Gas tank is under the *back seat* of most cars..."
that's nice. does this have anything to do with *his* tank being under the trunk? which is where "most" cars used to have it, and a hell of a lot still do.
if you're going to be tedious, at least don't be instantly dismissable. sit down, and take the moderator who gave you an informative rating with you.
Did you guys see Terminator 3? The robot used his batteries as bombs.
I doubt that the supposed violent explosion of cobalt oxide above 140F is violent enough to cause anything more than serious damage to the battery (duh! it don't work no more) and some minor damage requiring some duct tape to whatever the battery is attached to. From what I've read, it sounds like this:
Cobalt oxide is in Li-Ion batteries. Above 140F, cobalt oxide becomes cobalt and gaseous oxygen, and starts an exothermic reaction. The exothermic reaction causes itself to continue to get hotter and hotter, causing the oxygen to detach from the cobalt more and more rapidly into the sealed part of the battery that it's held in. At some point, the pressure builds to the point of violently breaking open the battery casing. You hear a loud pop and think "Holy crap! I could have died!"
This also sparks some curiousity towards the old Li-Ion battery from a cellular phone of mine that died a year ago. >:D
its under the boot in my car but perhaps that has something to do with the country i live in, where all cars have the tank under the boot
People- Calm. The. Fuck. Down. Planes don't explode because something inside them catches fire, they don't start crashing because someone shoots a gun, yadda yadda. Cars don't explode because a battery overheats in the trunk.
You simply don't know what you are talking about.
First, oxygen systems are NOT on planes to protect passengers from toxic gases and fumes. O2 systems are designed to provide oxygen for the short time it takes to get passengers from high altitude without brain-damage or death. More people die from exposure to toxic gases in aircraft fires than die from the fire or any fire-related impact.
Second, according to an April 2000 Flight Safety Week article [google it: in-flight fire safety week], the US airline industry faces three potential in-flight fire occurances every day. In 1998, well after your 1996 Valuejet "turning point", Swissair Flight 111 went down off New York with the loss of all passengers and crew as a result of an out of control electrical fire, in spite of fire-suppression and smoke alarms. TWA 800 exploded in mid-air because of an electrical short in a center fuel tank. In 1999 more than 960 smoke and in-flight fire events were recorded, resulting in 350 unscheduled landings of commerical airliners in the US and Canada alone. The majority are electrical fires, (but wouldn't a laptop battery fire be electrical?) although there are plenty of instances of non-electrical fires too - read on...
From the article:
* A very high number of smoke or fire events occur on transport aircraft in the US and Canada - 964 over 10 months.
* 478 were high-temperature events... [instarx comment: as opposed to smoke events. These were real events - all false alarms were exluded from the study.]
* A detailed look at 392 high temperature events showed that 80 percent involved electrical systems and components. [instarx comment: which means 20% were not electrical and resulted from items overheating on-board or from cargo. This translates into about 80 in-flight fires caused by items carried as part of or on commercial flights in 1999]
* In the overwhelming number of cases, the crew had limited ability to recognize, gain access to, or to control the malfunction.
* The resetting of tripped circuit breakers with internal or external short circuits generally made things worse.
* There is an average of more than one unscheduled landing a day due to smoke or fire based only on Service Difficulty Report (SDR) data.
* The SDR database under-reports the significance of the problem.
Your track record with the fire thing was so bad I didn't even start to investigate your other unfounded claims about guns fired not bringing planes down, or batteries in cars not causing fires.