Apple iPhone spontaneously combusts aboard flight in Australia
bgr.com
bgr.com
Shorting any battery will cause it to heat up, but lithium is a potent alkali metal. It reacts violently (as in fire and possible explosion) with water. The moisture in your skin will do just fine. Contrast this with other battery chemistries such as nickel-cadmium, which are practically benign by comparison.
Here's a great video illustrating the results of dropping bits of various alkali metals in to a bathtub full of water:
It does appear that Lithium's reactivity with water is has much more energy release potential than the battery itself does, but from a bit of reading around on the all-knowing internet, this reaction is supposedly fairly gentle. "Lithium's density is only about half that of water so it floats on the surface, gently fizzing and giving off hydrogen. It gradually reacts and disappears, forming a colourless solution of lithium hydroxide."
Seems to me that if you physically abuse a battery, it's going to release the energy that it has stored. The only way to really avoid that is to not store so much energy. Or are there battery chemistries that can take abuse without releasing their energy?
It's the runaway reaction that makes Lithium ion batteries less safe. They require pressure vents and special circuitry to make them safe as they short out if fully discharged after which attempting to charge them is unsafe.
The thing with batteries isn't just the amount of energy that they contain, but that it comes entirely pre-mixed and ready for instantaneous release.
As far as normal batteries withstanding physical abuse, I don't know. I certainly wouldn't try puncturing or badly overheating a regular battery, and wouldn't be surprised if such treatment caused it to release what it has. I could, of course, be wrong.
Here's an article about it happening:
http://www.wthr.com/story/15008952/13-investigates-exploding...
Considering how much more common standard batteries are, you can assume it is indeed pretty rare.
As for the energy density of sugar you're right that they're not really directly comparable but yeah I think it is more energy dense. Actually, wikipedia has a nice table for it:
http://en.wikipedia.org/wiki/Energy_density
I think we're actually in agreement here. My whole point was that the chemistry of how the energy is released is more important than the energy density.
http://www.badscience.net/2006/07/brainiac-fake-experiments-...
At this point rechargeable lithium-based batteries are a more effective bomb than 90% of the things the TSA has banned - but I suspect we won't see them trying to take away laptops and phones anytime soon.
"Fliers Must Turn Off Devices, but It’s Not Clear Why" https://news.ycombinator.com/item?id=3283768
Edit: Not implying anything about a relation to phone use during takeoff and landing (BGR and Australian press release are vague), but I just found it curious.
The original reason why the "no electronics during takeoff or landing" regulation was adopted reaches back to the assumption that you can cause an airliner's nav system to go out of whack with radio signals emitted from consumer electronics.
As far as I know this argument has turned out to be pure FUD. However, once a law or regulation is in effect, it is unlikely to ever be rolled back again - this is probably the reason why they simply switched out the rationalization for it to something else: they now say that electronic devices could turn into deadly shrapnel during takeoff and landing.
Like so many "security" and "safety" related things today, the fact that they make you switch off your iPod but don't actually force you to pack it away safely requires a certain amount of cognitive dissonance of all parties involved.
Our own lucasjung, who works in developmental flight testing, discussed this in the linked thread at https://news.ycombinator.com/item?id=3285481 and following.
It had something to do with FCC regulations and how you could somehow bypass some system and get free calls, or calls could not be billed correctly, perhaps it was data, but it certainly was cellular related.
I can't seem to locate the information now.
At any rate, it does seem strange, as they cell towers themselves are not being asked to shut down, and they certainly broadcast much greater signals than the actual cell phone. This signal is rained over the entire aircraft 24/7.
The concern being that should we start filling the floors of hybrid vehicles with these, that we are essentially deploying fast moving bombs on our streets, roads and highways, and all we're going to rely on is faith that someone isn't going to put a switched connection between two terminals and wait till they're parked outside a police station, abortion clinic or elementary school and just flip the switch.
Source: http://www.boeing.com/commercial/cabinair/facts.html
I do agree that the bite looks like a head, but it doesn't look the same as the one in the link above, especially when you take into account the missing "Steve Jobs" and "1955-2011".
I'd put it down to a freakish break line causing fragmentation around the bite. Backplate looks identical to mine (minus the damage).
We live in an era where a few brown-skinned men praying on an airplane is enough to trigger passenger panic and the involvement of the FBI. Do you really think that, if the above happened and the passenger was unfortunately of the wrong race, that passengers would not immediately jump to the "terrorism" conclusion? In the last few years passengers have jumped to that conclusion for way less.
[edit] I'm not saying this would've meant throwing someone into Gitmo and throwing away the key. But you have to admit, if this happened to anyone of Middle Eastern descent, there's not a chance he wouldn't have been detained and subject to a barrage of investigations.
Do I think racism is alive and well all around this country? How about, just guess, and then we can keep the discussion off HN. A few years ago, this might have been a thread about battery chemistry. Now it's about the TSA. I have to believe you think that's sad too.
[1] http://travel.usatoday.com/flights/post/2011/11/locked-in-la...
These kind of events can and routinely escalate just due to fear alone.
It is also often at the expense of specific colored individuals.
Is it really any surprise that the bulk of the discussion is applying to meatier, more interesting/controversial tangents?
In any case, my OP is not really meant to be a lightning rod for Yet Another TSA Bash(tm), but rather just an exasperated, cynical quip.
Anyways, I'm not trying to bag on you. My problem is with the whole site.
My time is valuable and the comment scores, albeit a flawed metric, served a good purpose to filter out some of the less useful/insightful comments, I wish there was a toggle in the preferences that would allow people to turn it on per user.
With the karma removed from comments, though, "witty joke with 7 upvotes" is now completely indistinguishable at a glance from "extreme insight with 100 upvotes".
I don't think it's realistic to expect people to stop joking about topic X, or making short quips about things... logically it makes sense to bring back some kind of way to differentiate these posts.
Don't be surprised though when the intelligent, compassionate people you're conversing with start noticing and commenting on the big bad police state that's been descending upon them.
I mean, sure you can offer the odd complaint now and then and hope others are with you or you can organize others around a complaint to see where that gets you. You could go directly to the controllers of the board and complain.
The path of least resistance is always there though. If you don't like where you're at and you have no effective way of dealing with it, the best thing to do is to relocate.
Anyway, I should not have been gruff about it earlier. It could have been said more politely. So I do apologize for that.
My theory is that it was already compromised somehow (maybe defective), and the pressure decrease popped the container(s). And to people claiming OMG CASE MOD, look more closely. A crack goes right through the line that would form the glasses. It could be a mod, but I highly doubt it.