Slashdot Log In
What's Wrong With Lithium Ion Batteries?
Posted by
samzenpus
on Thu Sep 06, 2007 04:15 AM
from the too-hot-to-handle dept.
from the too-hot-to-handle dept.
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."
Related Stories
[+]
Battery Powered Tram Charges in 60 Seconds 176 comments
SK writes to tell us that a new streetcar, powered by lithium battery, has been invented by the Railway Technical Research Institute in Kokubunji, Tokyo. The new transport is capable of speeds of 40 kph for 15 kilometers and can convert 70 percent of its deceleration energy into electricity which is then sent back to the battery which can recharge in under one minute.
[+]
Nanowires Boost Laptop Battery Life to 20 Hours 238 comments
brianmed writes to tell us that Stanford researchers have created a new use for silicon nanowires that promise to reinvent lithium-ion batteries. "The new version, developed through research led by Yi Cui, assistant professor of materials science and engineering, produces 10 times the amount of electricity of existing lithium-ion, known as Li-ion, batteries. A laptop that now runs on battery for two hours could operate for 20 hours, a boon to ocean-hopping business travelers. [...] The lithium is stored in a forest of tiny silicon nanowires, each with a diameter one-thousandth the thickness of a sheet of paper. The nanowires inflate four times their normal size as they soak up lithium. But, unlike other silicon shapes, they do not fracture."
This discussion has been archived.
No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
Full
Abbreviated
Hidden
Loading... please wait.
Lithium Ions (Score:5, Funny)
And isn't that what a battery per definition has?
Re:Lithium Ions (Score:5, Funny)
Well, many designs feature a salt and battery; personally, though, I always thought that just because you have bipolar to point at doesn't mean you get off without a charge. From where I sit, the whole bunch of them belong in cells.
Parent
Re:Lithium Ions (Score:5, Funny)
Parent
Re:Lithium Ions (Score:5, Informative)
Parent
Dear moderators (Score:5, Insightful)
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.
Parent
What a moronic post (Score:4, Insightful)
Actually, if you RTFA, it's not moronic (Score:5, Insightful)
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 [fda.gov], 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.
Parent
Re:Actually, if you RTFA, it's not moronic (Score:5, Insightful)
You have this process of designing, manufacturing, and assembling a product that has worked well for a number of years. You can outsource the assembly to China, and you should get the same results as you did with your Japanese plant. Your Chinese partners are supposed to set up an identical assembly line, train the workers exactly the same way, etc.
On paper, you seem to have the same process, only cheaper. On the other hand, you don't know if the Chinese workers hired will be as good as your Japanese workers, even if you train them identically. You don't know if your Chinese partner, who is making his profit out of the difference between his costs and your costs to do the same thing, isn't cutting some corners. You don't know if the lax Chinese regulatory process will affect how the work is done or the performance or attitude of the workers.
On the other hand, if you don't do it, you don't know if your competitors will do it and undercut your prices.
We talk a lot about taking risks in capitalism, but sometimes we talk as if risks always pay off. They don't. Part of the process of capitalism are businesses trying strategy B, which should be equivalent to strategy A, and finding out that it isn't. Maybe you go back to A, or you try to tweak B to get the same results as A. Big trends like the dot com bubble or outsourcing to India or China sweep a lot of people along who aren't really ready to assume to risk or prepared to make things work. By in large the answer tends to be it sort of works, but not quite as well as you would hope, and you have to master the differences.
Parent
Re:Actually, if you RTFA, it's not moronic (Score:5, Insightful)
Parent
Re:What a moronic post (Score:5, Insightful)
Parent
Re:What a moronic post (Score:5, Insightful)
Parent
Re:What a moronic post (Score:5, Funny)
Parent
Re:What a moronic post (Score:5, Insightful)
Parent
Stone tools? (Score:5, Funny)
Parent
Re:What a moronic post (Score:5, Insightful)
Needn't be bankrupcy, btw. Waving the "if we gotta pay, we gotta cut costs and that means we gotta lay off" flag is often enough of a warning to get you off the hook cheaply.
Parent
Some stuf I wrote on this a while ago (Score:5, Interesting)
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
Re:Some stuf I wrote on this a while ago (Score:5, Informative)
This is (lately) misinformation. It's basically true of any conventional LiIon battery type. But unlike the LiIon chemistry in common use today in laptop batteries, the newer lithium phosphate (LiFePO4) LiIon chemistry is inherently non-flammable and non-explosive. It's also considerably less energy dense than standard LiIon chemistries and more expensive to manufacture, thus big business' near-total lack of interest in rushing to develop it for consumer devices over the past several years. But it is now used in a few high current drain applications where conventional LiIon would be a poor choice, e.g. in some DeWalt power tools. When the cost comes down enough, you'll see lots more of these batteries, notably in electric vehicles, where they effectively eliminate laptop-type LiIon's barely-restrained violent urge to turn vehicles into smoldering heaps of rubble.
See http://en.wikipedia.org/wiki/Lithium_iron_phospha
Parent
Fortunately (Score:5, Interesting)
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 [arstechnica.com] 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.
that won't solve problems (Score:5, Insightful)
Existing capacitors in your computer can make quite a boom...
Parent
OMG! Invented by Sony! (Score:5, Funny)
Lithium polymer, not all lithium batteries (Score:5, Informative)
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.
Re:Lithium polymer, not all lithium batteries (Score:5, Informative)
The got a big writeup in the September issue of IEEE Spectrum: http://spectrum.ieee.org/sep07/5490 [ieee.org]
Parent
The reason behind the problem is simple (Score:5, Interesting)
No, the reasons are not ambiguous, they are clearly outlined. There is nothing wrong with the technology, the entire problem is the lack of quality control in battery factories in China. Sony is not the only one to get screwed by poor QC in Chinese factories, so has Mattell who are scrambling to recall ~20 million toys painted with lead paint [www.ctv.ca], and J&J, who are scrambling to recall 10 million fake diabetes kits [bloomberg.com]
In the article itself, fingers are clearly pointed
I don't think anybody realizes just how shoddy quality control is in China. Just as there is absolutely no respect for intellectual property, the Chinese, being new to capitalism, don't understand the value of quality control. They've never had to suffer the consequences of legal action.
The culture just does not exist. Some argue that this is a good sign, a necessary phase in capitalism that China is passing through that the USA passed through once before [boston.com].
I'm not trying to be a troll. China I'm sure will improve and their industry is surely chastened by the huge hue and cry around the world. But until things get better, watch out, and for more than just exploding batteries:
Just setting the record straight
Re:They only started doing this recently (Score:5, Interesting)
http://www.electronicsweekly.com/blogs/engineerin
Even better there's a link to that article in the writeup! Pretty handy.
Parent
Re:What's wrong? They store to much energy! (Score:5, Interesting)
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.
Parent