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Dell's Exploding Laptop Autopsy

Posted by ryuzaki0 on from the determining-the-cause-of-aaaughh dept.

An anonymous reader writes "Dell has gone to the Consumer Product Safety Commission looking for help determining the cause of death for its exploding laptop. Dell has been blaming the lithium ion battery; the commission seems to have had a few problems with those batteries in the past."

6 of 141 comments (clear)

  1. Li-Po use in RC by Spiked_Three · · Score: 5, Interesting

    I play with a lot of R/C stuff - planes, helicopters etc. And the warnings about Li-Po batteries are pretty explicit. If you where to crash a plane with a Li-PO you need to set the battery in a fire proof container and keep an eye on it for an hour or so. Also never charge Li-Po un-attended - people have burned down houses because of it.

    I suspect the laptop had a hard drop sometime in the not to distant past, got picked up, put on charge and kaboom.

    The question is what is the right thing to do? Ban the batteries or make better efforts in consumer education? In the R/C hobby we are smart enough (well the majority anyhow) to treat Li-Pos with respect - but consumer laptops, that's somewhat scary.

    http://www.laureanno.com/RC/fire-pics.htm

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  2. It's the charger stupid.... by khb · · Score: 5, Interesting

    That batteries can explode is no secret. Managing the charging correctly is critical ... and a battery which is on the road to exploding has lots of "markers" (fast heat rise, wrong charging profile, etc.).

    It seems to me that low margins are the root cause ... for the battery vendor to have QA practices that allow marginal batteries, and for Dell (since they are the ones being fingered, not because I know anything about their practices) to skip additional safety logic beyond whatever minimal standards the battery vendor has specified.

  3. Plugged in? by shabushabu · · Score: 5, Interesting
    I searched TFA but couldnt find the answer to what I believe is a critical question. Was the laptop plugged into an AC outlet when it exploded? If so, even a short could cause an explosion.

    On the other hand, if the battery exploded entirely by itself, a major recall is due...

  4. actually, I've seen the reverse.. by YesIAmAScript · · Score: 3, Interesting

    I work with Lion and Li-Poly batteries at work and in R/C.

    I find the RC folks are reckless when it comes to Li batteries. At work, the device that uses the battery has an overvoltage, over temp and undervoltage cutout in hardware in addition to overvoltage, over temp and undervoltage cutouts in software. The battery also has a hardware overcurrent and undervoltage cutout on the cell. This is because the device maker cannot afford to trust the battery and the battery maker cannot afford to trust the device maker, because LIons are just too sensitive to temp, voltage and current.

    RC folks meanwhile typically have software undervoltage cutouts but no hardware cutouts on the device. They remove the hardware cutouts on the cell. They use separate chargers that have software overvoltage and overcurrent cutouts and no temp cutouts.

    They are many many more times at risk than a consumer device. They get away with it by being careful themselves and because there are 1/100000th as many RC devices as consumer devices.

    As to your thing that batteries can blow up after having been in a crash, I don't know where that comes from. Unless the integrity of the pack is compromised, this won't happen. They don't turn into bombs merely by being shaken. If they did, you'd have exploding cell phones everywhere.

    Your charger should monitor the temp, current and voltage during charging. If a pack has developed an internal short due to physical damage, it should stop charging. But again, RC chargers seem to be less careful.

    (I have an Orbit Microlader. Earlier units were even more primitive!)

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    1. Re:actually, I've seen the reverse.. by Fishead · · Score: 3, Interesting

      "As to your thing that batteries can blow up after having been in a crash, I don't know where that comes from. Unless the integrity of the pack is compromised, this won't happen. They don't turn into bombs merely by being shaken. If they did, you'd have exploding cell phones everywhere."

      If the cell dents, there is a possibility that the Anode can short to the Cathode through the thin insulative seperator. This will cause a short that the pack/device has no control over and you get fireworks.

      Or, the guts of the cell can shift and press into the bottom and short.

      Or (much less likely) if there is some impurity in the mix, it can cause it to shift and puncture the thin seperator.

      The cells are actually designed to permanently disconnect inside under certain circumstances to prevent (or at least minimize) crashing airplanes and killing children.

  5. Re:So there are two cases now? by Traiklin · · Score: 3, Interesting
    Blaming the battery is laughable. I guess what Dell is trying to say is that they [Dell] don't add any value to the parts the sell!?
    and what happens if it is the battery that is to blame? Like the summery says this isn't the first time Lithium Ion batteries have caused problems.

    I dislike dell as much as the next guy (mainly I am tired of all prebuilt PC's anymore, they are so locked down and full of useless shit that I can't properly upgrade them) but when something isn't a company's fault then they shouldn't get the blame for it.

    I remember cell phones were blowing up in peoples pockets and when they were using them, was it the cell phone makers fault? no cause they said it was the batteries and it was proven to be the batteries, Was it laughable that they were blaming batteries instead of taking the blame for making a phone out of lower value parts?