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What's Wrong With Lithium Ion Batteries?
An anonymous Coward writes "Lithium ion batteries short-circuit. They overheat. They burst into flames. The reasons behind the recent spate of problems with a technology invented by Sony more than a decade ago are complex and varied, making for one big engineering headache."
Yeah, but they're great for bipolar disorders.
And isn't that what a battery per definition has?
http://www.theinquirer.net/?article=14417
I wrote that before batteries going boom was the latest fashion trend. The problem is simple, you have a lot of energy in a small area and people crying out for higher densities. If _ANYTHING_ goes wrong, you have a high likelihood for a lot of energy released in a short amount of time.
Couple this with reactive/flamable substance that make up batteries, and you have a lightshow. There is no magic to it all, simple physics. Lots of energy released around reactive things, you need both for a modern battery.
Some designs minimize the risk, none remove it. As always, nothing new under the sun.
-Charlie
Fortunately, we have supercapacitors. While they're not there yet for energy density (still about 10x too little) they're rapidly improving. 10x isn't much at the rate these things have been improving, and there are plenty of labs with pieces that are much better than currently available commercial offerings, but that still need development work. If I had to guess, I'd say it's 5 years until the first supercaps appear in serious commercial use, and less than 10 until LiIon has gone the way of NiMH.
Of course, if you believe the rumors then it might be even faster than that -- we might be seeing serious applications in a year or so.
I, for one, will be glad to give LiIon a proper burial. But until then, we work with what's available.
http://www.electronicsweekly.com/blogs/engineerin
Even better there's a link to that article in the writeup! Pretty handy.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Acually, if you actually RTFA, it raises exactly the same problems you write about, so I'm curious how you could call it moronic without, you know, calling yourself a moron ;)
That said, I still have to wonder about some tradeoffs. Essentially, the way I read the article:
1. A lot (if not most) of the increasing risk was in the name of cutting costs as such, or cost per capacity. E.g., the original Cobalt, which was expensive but apparently safe, got then replaced with Nickel, then with even cheaper Nickel-Manganese alloy. I'm not sure how that can be a problem, but _something_ (this or something else) along the way apparently turned a safe battery design into a potential time bomb.
2. (Or maybe 1a.) They seem to be blaming the factory in China where everyone outsourced the actual manufacturing to. Again in the name of cutting costs. Maybe it's just blame-shifting and finger pointing, but it raises a valid theoretical concern. It's not easy to know, once a battery is assembled and sealed, what really is inside. If, theoretically, they shafted you for an extra buck, how would you know? You can put all sorts of checks in place in your own factory, but once you've outsourced it, it's out of your control.
It even gives you an example of what can go wrong in that scenario. If the separating membrane doesn't soften and collapse at a given temperature, the battery essentially just lost the designed protection against catching fire. What if someone replaces that foil with something cheaper, but which doesn't work that way?
3. (Or maybe 1b.) Apparently at least one batch is suspected to have been manufactured with counterfeit materials. I have to wonder if this wasn't just because they were cheaper. I.e., cost cutting again.
4. Not cost cutting, but competitive advantage again, apparently some laptop manufacturers recharge their batteries more "aggressively" (read: exceed the rated recharge current) so they can get a minor competitive edge there. It apparently (according to TFA) causes the battery to vibrate, and might cause particles to impale the membrane and shortcircuit the battery.
So while I'm not against capitalism or anything, it makes me, you know, wonder. Maybe the drive to cut costs can be taken to dangerous extremes? Just a thought.
Yes, it should fix itself, companies would in an ideal world avoid loss of reputation due to faulty products, etc. But sometimes it's too late. E.g., it's already suspected that a plane crash was due to a laptop igniting in the hold. E.g, an even worse case was when in 1937 a pharma company offered a liquid antibiotic where the actual antibiotic wasn't solluble in water, but someone found out it was solluble in diethylene glycol, a deadly poison. It was what prompted the FDA to mandate extensive testing for medicine. (And speaking of diethylene glycol, it seems to keep reappearing recently in Chinese-manufactured toothpaste. No doubt because it's cheaper than something less toxic.) Etc.
Do I have a solution? Nope. It makes me wonder, though.
A polar bear is a cartesian bear after a coordinate transform.
The batteries that are causing troubles now are all Lithium polymer batteries. The electrolyte-fluid in them has been replaced with a polymer that amongst other things made it possible to replace the heavy metal cylinder with aluminium/plastic packaging and make the battery in all kinds of forms.
Unfortunately, at the same time the chemistry of the cells was changed such that if a thermal runaway ever happened, the venting gasses would ignite with oxygen and would ignite the cells next to it too. That is exactly what is happening.
I am rather supprised that no one yet has mentioned A123 systems. They make/market a new type of lithium-(nano)phosphate cell, that has none of the drawbacks of lithium-polymer batteries. They will not catch fire in a thermal runaway or when pierced, can be much more abused than LiPos and have a much longer lifespan to boot (2000 cycles instead of 500). It's no wonder that these batteries will be in the next generation of hybrid cars, as they weigh half as much as the NiMH batteries used now (LiPo would be too dangerous in a collision) and can generate much more current too. (~10C for NiMH, ~40C for A123).
So there is hope one the battery technology front, it's just that the current best option is a bit dangerous.
This space is intentionally staring blankly at you
I saw Fight Club too
It's inherently dangerous because very high energy-densities nessecarily mean that there's a lot of energy there to be released. Also, everything for that reaction to occur, must be contained inside the battery. (well, if you exclude air-breathing batteries)
It can be made more or less safe, but normally at a cost of reduced energy/pound. This ain't just so for batteries, but for literally *anything* storing large amounts of energy.
Natural gas has certain failure-modes that are ahem, unpleasant. The failure-modes become more likely as you increase the pressure and/or decrease the mass of the container used to hold the gas.
A flywheel used to store a large amount of energy would be unpleasant if it where to ever disintegrate, get out of balance, or somehow drop out of the bearings. All of which become more likely the higher the energy stored and the less material used for securing against these possibilities.
And yeah, batteries, especially those with high energy-densities, have unpleasant failure-modes. If you where willing to accept a twice-as-heavy battery with the same energy-content, these could be made less likely. Hell, even if you where willing to pay more for an equal-capacity battery, the failures could be made less likely. Still, they're always gonna be there.
Dear moderators.
There IS NO -1 Unfunny.
You can not and should not use -1 Overrated or -1 Offtopic as a substitute if you don't find something funny. The reason being that the poster does not get karma for the +1 Funny, but you will burn his karma when you mod him down.
+4 Funny
-2 Overrated
Net effect:
+2 Funny, but with a -2 karma penalty.
If you don't find something funny, leave it alone and don't moderate it!
If anything, every +1 Funny is a penalty in itself, as they prevent moderators from adding more +1 Insightful/Informative points once it hits the ceiling.
And no, this post is not -1 Offtopic, as it is directly relevant to the parent. Thread drift is to be expected, and should not trigger Offtopic moderation. Thread jumps should be penalized, when they occur, but the children of a post are not -1 Offtopic if they address anything written in that post. If every post were to relate to the original article and not the post you actually reply to, there would be no need for a thread system. Since there is one, expect and accept thread drift and topic drift.