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Power Technology

What's Wrong With Lithium Ion Batteries? 289

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."
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What's Wrong With Lithium Ion Batteries?

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  • by joto ( 134244 ) on Thursday September 06, 2007 @04:30AM (#20491685)

    Anything that contains lots of energy in a small and compact volume, is dangerous. Explosives, and modern batteries, are really not that different. Both contain a huge amount of energy, in a comparatively small area. As battery technology improves, batteries will become even more dangerous.

    With old heavy duty, or alkaline batteries, the worst that could happen was usually a leak. While annoying, it usually didn't pose any dangers. Modern batteries catch fire and explode. Eventually, we'll probably have a nuclear powerplant inside our mp3-players, at which time, they will hopefully include some additional safeguards, such as a fuse. But all modern batteries (lithium, lithium-ion, lithium-polymer) will explode or catch fire, if there's a serious enough malfunction.

  • by sslo ( 1143755 ) on Thursday September 06, 2007 @05:07AM (#20491891)
    "Couple this with reactive/flamable substance that make up batteries, and you have a lightshow. ... Some designs minimize the risk, none remove it."

    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 e_battery/ []
  • by nietsch ( 112711 ) on Thursday September 06, 2007 @05:53AM (#20492101) Homepage Journal
    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.
  • Re:Lithium Ions (Score:5, Informative)

    by 2.7182 ( 819680 ) on Thursday September 06, 2007 @06:31AM (#20492267)
    The joke - Lithium has been a standard treatment for bipolar disorders since the late 50's. It can work remarkably well. Funny thing is that it was discovered by giving it to rats. The rats calmed down though because it made them sick, and this was misinterpreted. But it works well in humans by coincidence.
  • by enrevanche ( 953125 ) on Thursday September 06, 2007 @06:40AM (#20492313)
    They were first released commercially by Sony, they were not invented by Sony.
  • by dgun ( 1056422 ) on Thursday September 06, 2007 @06:44AM (#20492337) Homepage

    Engineers face difficult challenges all the time....

    Safety is routinely traded against cost and size.

    And if safety, cost, and size were not "specified", batteries would be huge, cost $25,000 a piece, and would explode when dropped.

  • by 1u3hr ( 530656 ) on Thursday September 06, 2007 @07:36AM (#20492623)
    There's nothing preventing a battery pack composed of individual smaller batteries, combining to almost any shape you want. As long as you could change the individual cells that'd be fine.

    That's the situation now actually. There are shops here (in Hong Kong) that will sell you a third-party laptop battery; or they'll crack open your old one and rebuild it with standard LiOn cells. Similar ro laser toner refillers. Don't they have this elsewhere? Perhaps liability concerns prevent it in the US.

  • by sslo ( 1143755 ) on Thursday September 06, 2007 @07:45AM (#20492673)
    The Wikipedia lithium phosphate battery link with better formatting: e_battery/ [] The Energy Blog is a source of some good up to date information about automotive power developments using safer lithium phosphate LiFePO4 batteries: The Energy Blog, at s/ [] It talks about the upcoming GM Volt car, airship batteries, A123 Systems batteries (used for several years now in power tools) moving into automotive use, Altair NanoSafe batteries being used in electric pickup trucks, Mitsubishi's investment in a LiFePO4 battery manufacturing plant expected to produce vehicle batteries in 2008, and Nissan and NEC combining to invest in a safe automotive lithium ion battery manufacturing plant with products expected in 2009. In response to the many sweepingly inaccurate comments above about high energy density batteries being inherently unsafe, energy density alone does not make a chemical battery spectacularly dangerous. The LiFePO4 batteries appear to be roughly as safe as alkaline or NiMH cells (which have a broadly similar energy density per volume, but aren't as energy dense by weight). Lithium primary (disposable) 3.0v cells are not nearly as safe as alkaline and NiMH, despite being approximately as energy dense. When made with good quality control, they're reasonably OK to use in devices that use only one lithium cell. Even then, when poorly manufactured, they can overheat and burn or explode. They are not really reasonably safe to use in devices that use two or more cells in series. LiIon batteries of the conventional kind are also notably more unsafe when two or more such cells are used in series.
  • by Televiper2000 ( 1145415 ) on Thursday September 06, 2007 @07:57AM (#20492751)
    It's all about size, weight, and the abusive charge cycle that laptops and cellphones are required to go through. From what I've read, the thing that really stands out for lithium batteries is the lack of cell memory. Here's a link comparing 4 battery types: []
  • by Rob the Bold ( 788862 ) on Thursday September 06, 2007 @08:15AM (#20492891)

    I am rather supprised that no one yet has mentioned A123 systems.

    The got a big writeup in the September issue of IEEE Spectrum: []

  • Re:Lithium Ions (Score:4, Informative)

    by jimstapleton ( 999106 ) on Thursday September 06, 2007 @08:21AM (#20492931) Journal
    I thought it was something different.

    The goal was a treatment for personality disorders, but they were studying ammonia (or something similarly revolting sounding), and they had to put it with a co-molecule/atom to give it the right properties. They tried with several different associate atoms/moleculres. Anyway, the results showed no effect whatsoever, except with the co-molecule being lithium. They concluded the lithium was what they wanted, not the ammonia.
  • by TheRaven64 ( 641858 ) on Thursday September 06, 2007 @08:25AM (#20492945) Journal
    The first laptop I owned (386) had a proprietary battery. On closer inspection, it turned out that this was a simple enclosure containing 9 (or maybe 12) C cells wired together. Cracking it open, replacing the cells, and duck taping it back together was a lot cheaper than buying a new one from the manufacturer.

    I'm a lot more wary of third party battery replacements with Lithium-based cells. Once you get to this kind of energy density, you basically have a bomb and a small circuit trying to persuade it not to explode. In this situation, I'd much rather I knew exactly who to hold responsible if the circuit failed. Last time I checked, third party batteries for my current laptop were only 10% cheaper than original ones, so it's not worth the risk (especially since it is likely to invalidate the warranty on the rest of the machine should the battery damage it, and the computer is worth much more than the battery).

    One thing I've noticed in recent years is that it's become a lot harder to charge batteries outside the laptop. It used to be that you could have two batteries, one charging and one in use, and just pop inside to swap them periodically. Now, most laptops seem to only be chargeable inside the laptop, dramatically reducing the usefulness of the second battery.

  • Re:Lithium Ions (Score:0, Informative)

    by Anonymous Coward on Thursday September 06, 2007 @08:39AM (#20493055)
    I'm pretty sure it was discovered because there were springs which people sent mentally ill people to because they noticed they found relief. Later, it was discovered that those springs contained higher than usual concentrations of lithium ions.
  • by timster ( 32400 ) on Thursday September 06, 2007 @08:57AM (#20493201)
    Chemistry is Physics without all the crap about gravity. Which is why chemists are able to get real work done while physicists have spent the last 100 years on little more than the problem of how to get gravity right.
  • Re:Lithium Ions (Score:1, Informative)

    by Anonymous Coward on Thursday September 06, 2007 @10:11AM (#20493985)
    Jesus Christ, some duchebag moderator went through every post under the parent modding it as -1: Off-topic. Lighten up people!

10.0 times 0.1 is hardly ever 1.0.