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What's Wrong With Lithium Ion Batteries?

Posted by samzenpus on 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."

6 of 289 comments (clear)

  1. Some stuf I wrote on this a while ago by Groo+Wanderer · · Score: 5, Interesting

    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

    1. Re:Some stuf I wrote on this a while ago by Anonymous Coward · · Score: 4, Interesting

      You cannot derive physical laws from mathematical theorems


      This is a fairly recent (i.e. C19) viewpoint, reflecting changing understanding of what mathematics is. Neoplatonists such as Galileo and Kepler, and synthetic geometers adopting the classical style, would have been happy to tell you that mathematics is a perfect way of describing nature.

      Then the axiomatisers, perhaps heralded by Leibniz (whose more philosophical discussions on notation etc were of less immediate influence than his calculus, even though one begat the other), decided that mathematics was nothing more than a set of rules for symbol manipulation. Hence, for example, the arguments over Euclid's parallel postulate being initially connected with the question of whether geometry is "true" in the sense that it represents physical space.

      In essence, you are vacuously correct, because today, mathematics without choosing some axiom system cannot do anything - it is merely an acceptance of "logic" without any definitions or rules to work from. But if we choose our axiom system to incorporate sufficient fundamental laws of physics, then physics becomes a branch of mathematics; just as if we choose our axiom system to be Euclid's definitions and postulates, Euclidean geometry becomes a branch of mathematics.
  2. Fortunately by evanbd · · 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 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.

  3. Re:They only started doing this recently by Hal_Porter · · Score: 5, Interesting
    I found an interesting article that supports that theory -

    http://www.electronicsweekly.com/blogs/engineering -design-problems/2007/09/whats-wrong-with-lithiumi on-ba-1.html

    But Don Sadoway, a professor of Materials Chemistry at MIT who is an expert in advanced battery technologies, worries about off-shoring of a chemistry he asserts "needs to be treated with respect."

    "I have 100% confidence in the Japanese battery manufacturers," he says. "And my guess is that they never had the problems theyre seeing now when the same batteries were manufactured from start to finish in Japan."

    He notes that one of the challenges with Li-ion batteries in particular is that it is very difficult to verify that the manufacturing and assembly is being performed according to specifications. Thats because once its assembled into a battery pack, the device cannot be inspected from the outside nor can it be easily tested.

    Sadoway points to the separator material between the electrodes as an example. Acting like a kind of fuse, it is designed to soften and collapse at a specific temperature, causing the battery to essentially go into an open circuit condition and die.

    In fact, he wonders why that didnt happen in the case of the Dell laptop that burst into flames last year.

    "You could think you are specifying a porous polypropylene material for the separator, but once the thing is packaged up you would have no way of knowing what you actually got. Even under the best of circumstances, you can get screwed by your own job shop. What if the workers took a short cut and substituted the original material with cardboard?"

    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;
  4. The reason behind the problem is simple by harlemjoe · · Score: 4, Interesting
    The Coward who posted this writes:

    The reasons behind the recent spate of problems with a technology invented by Sony more than a decade ago are complex and varied,

    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, and J&J, who are scrambling to recall 10 million fake diabetes kits

    In the article itself, fingers are clearly pointed

    But Don Sadoway, a professor of Materials Chemistry at MIT who is an expert in advanced battery technologies, worries about off-shoring of a chemistry he asserts "needs to be treated with respect."

    "I have 100% confidence in the Japanese battery manufacturers," he says. "And my guess is that they never had the problems they're seeing now when the same batteries were manufactured from start to finish in Japan."

    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.

    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 ...
    --
    shooting is not too good for my enemies
  5. Re:What's wrong? They store to much energy! by Eivind · · Score: 5, Interesting

    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.