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Power Technology Hardware

Engineers Explain Why the Galaxy Note 7 Caught Fire (digitaltrends.com) 289

Engineers with manufacturing technology company Instrumental tore apart a Galaxy Note 7 to try and figure out what may have caused some devices to overheat and explode, causing Samsung to recall and eventually cancel all Galaxy Note 7 devices. In their damning new report, the engineers discovered the root of the problem appears to be that the battery is too tightly packed inside the body of the Note 7. Digital Trends reports: They discovered the battery was so tightly packed inside the Galaxy Note 7's body that any pressure from battery expansion, or stress on the body itself, may squeeze together layers inside the battery that are never supposed to touch -- with explosive results. Batteries swell up under normal use, and we place stress on a phone's body by putting it our pocket and sitting down, or if it's dropped. Tolerances for battery expansion are built into a smartphone during design, and Instrumental notes Samsung used "a super-aggressive manufacturing process to maximize capacity." In other words, the Galaxy Note 7 was designed to be as thin and sleek as possible, while containing the maximum battery capacity for long use, thereby better competing against rival devices such as the iPhone 7 Plus and improving on previous Note models. The report speculates that any pressure placed on the battery in its confined space may have squeezed together positive and negative layers inside the cell itself, which were thinner than usual in the Note 7's battery already, causing them to touch, heat up, and eventually in some cases, catch fire. Delving deeper into the design, the engineers say the space above a battery inside a device needs a "ceiling" that equates to approximately 10 percent of the overall thickness. The Galaxy Note 7 should have had a 0.5mm ceiling; it had none.
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Engineers Explain Why the Galaxy Note 7 Caught Fire

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  • by OneHundredAndTen ( 1523865 ) on Monday December 05, 2016 @06:06PM (#53428093)
    This is bad. Very bad. If substantiated, the lawsuits against Samsung are going to be epic.
    • by delt0r ( 999393 )
      Only in America. The lawyers are laughing all the way to bank.
    • Samsung is already on the hook according to the legal doctrine of res ipsa loquitor. Mobile phones aren't supposed to catch fire in you pocket. If they do, especially if lots of them do, the rebuttable presumption is that it's the manufacturer's or designer's fault. While there may be finger pointing between manufacturer and designer, California product liability law allows you to go after any link in the chain of commerce that is most convenient for you. In other states or countries, YMMV.
      • by mkoenecke ( 249261 ) on Monday December 05, 2016 @06:48PM (#53428411) Homepage
        Different concept. Res ipsa loquitur means "the thing speaks for itself." It means no interpretation of a fact or piece of evidence is necessary. You're thinking of the concept of "strict product liability:" when a product causes damages, one does not need to prove actual negligence, just that the product caused the damage.
        • Different concept. Res ipsa loquitur means "the thing speaks for itself."

          But Thing never spoke for itself. It was Cousin Itt who spoke for itself. Thing could only knock. Geeze, don't you know nothin'?

        • by Chmarr ( 18662 ) on Monday December 05, 2016 @10:10PM (#53429625)

          Yes, that's the translation of the latin, but it's use in law is correct as to "accident implies negligence". Please read beyond the first sentence in Wikipedia.

          • by MrKaos ( 858439 )

            Yes, that's the translation of the latin, but it's use in law is correct as to "accident implies negligence". Please read beyond the first sentence in Wikipedia.

            You don't get modded up for deeper knowledge, only the perception of it.

    • The important takeaway here, if we're keeping things in perspective, is Thank Goodness! quality and safety are hardly ever compromised by manufacturers for fun and profit.
  • Why are there not physical insulators between the "risky" parts instead of merely air gaps? I'm not a psychical* engineer, so am I missing something? Do physical protection layers reduce cooling or something?

    * I don't mean I'm virtual, but that I don't engineer physical stuff. Software.

    • by Tablizer ( 95088 ) on Monday December 05, 2016 @06:12PM (#53428141) Journal

      Correction, I meant "physical engineer". But if you were a psychical engineer, you'd know that already.

      • by AmiMoJo ( 196126 )

        It had to be 0.01mm thinner than the last model, so no room for the battery to expand into.

      • by Jeremi ( 14640 )

        Eh, I think you meant "mechanical engineer"(*)

        (*) I don't mean a robot who is trained in engineering, I mean a human being who designs physical objects ;)

    • Physical separation adds weight and cost. There is no need for the extra material if you ensure an adequate gap, so why include it all? It's wasteful.

      I doubt the battery company only sells to Samsung, so other products are presumably using the same components safely. Samsung did the risky/bad engineering by shrinking the battery compartment as much as they did.

      Even with physical separation, the battery still needs room to expand. Perhaps your failure mode would be strained PCBs and cracked soldering instead

    • by Altrag ( 195300 )

      Air _is_ an insulator. Its the same idea as double pane windows.

      • Re:Why air gaps? (Score:4, Informative)

        by newcastlejon ( 1483695 ) on Monday December 05, 2016 @07:08PM (#53428587)

        Air _is_ an insulator. Its the same idea as double pane windows.

        Double glazed windows have a vacuum (or sometimes a noble gas) between the panes. If air gets in between the panes condensation starts to appear in cold weather. If that happens the window has to be replaced; they can't be repaired economically.

        • Re:Why air gaps? (Score:4, Insightful)

          by swillden ( 191260 ) <shawn-ds@willden.org> on Monday December 05, 2016 @09:13PM (#53429315) Journal

          Double glazed windows have a vacuum (or sometimes a noble gas) between the panes.

          Or dry air. There's no need to use anything other than air to avoid condensation. You just need to make sure the air is dry and the windows are sealed so humid air can't get in. I doubt many windows are vacuum-filled; that's just begging for trouble, and would also limit the size of panes. 15 pounds per square inch adds up to a lot of pressure very quickly.

          • Re:Why air gaps? (Score:5, Informative)

            by Streetlight ( 1102081 ) on Tuesday December 06, 2016 @12:54AM (#53430379) Journal
            Double or triple pane windows usually have argon as the fill gas as both its higher molar mass and smaller molecular size than the diatomic major molecules in air increase its insulation ability because of reduced thermal conductivity. It's also naturally water free if provided from liquid argon which is generally available. FYI, the thermal conductivity of a gas is proportional to the square root of molar mass and inversely proportional to the square of the molecule's diameter. At least that's true for real gases at atmospheric pressure which behave nearly like ideal gases
        • by ELCouz ( 1338259 )
          It's the desiccant stored in the glazed window internal frame that keep the moisture out.
          Once it leaks air the desiccant is saturated and moisture appear on the pane.
          Argon or other noble gas is just a gimmick...like filling your tires with nitrogen.

          Disclaimer: I work in the glass industry.
  • by JoeyRox ( 2711699 ) on Monday December 05, 2016 @06:08PM (#53428111)
    Theory sounds plausible but doesn't carry much weight without experiments that demonstrate the internal battery components actually making contact as a result of the factors they describe.
    • by delt0r ( 999393 )
      the TFA says "engineers" so it must be true.
      • by sexconker ( 1179573 ) on Monday December 05, 2016 @07:49PM (#53428823)

        Software "engineers" at best.
        This is the company in question. https://www.instrumental.ai/te... [instrumental.ai]

        It's a small startup of 9 people with no history. None of the people are even listed as mechanical engineers. They're all software engineers (which isn't a recognized profession, by the way) and business people. Not a one among them has the authority to make any claims about the Note 7. None of them have the actual experience with the Note 7 to do so either - they had a single sample that they couldn't actually do anything with other than write the blog post and fish it out to tech sites for hits and to get their name out there.

        • They're all software engineers (which isn't a recognized profession, by the way)

          Thanks but I won't take your word for that. Please show your reasoning.

          If a software professional can be a member of a recognised professional engineering body - they can be a "Certified Practicing Engineer" just like any other engineer - then I would say that they are by definition a recognised profession.

        • by lgw ( 121541 )

          They're all software engineers (which isn't a recognized profession, by the way)

          You're not a real engineer unless you roll the petard up to the castle gate! These new-fangled train drivers aren't real engineers at all!

  • ....and this was not caught during testing because?
    • Re:Interesting (Score:5, Insightful)

      by Yvan256 ( 722131 ) on Monday December 05, 2016 @06:11PM (#53428133) Homepage Journal

      1. Design ultra-thin phone
      2. Disregard warnings from engineers
      3. Profits!

      • Re:Interesting (Score:4, Interesting)

        by Darinbob ( 1142669 ) on Tuesday December 06, 2016 @03:36AM (#53430785)

        Engineers are basically people who keep saying "it can't be done in under budget and on time!" Which is why most companies now have products designed by marketing and sales. CEOs don't like workers who keep telling the truth.

    • ....and this was not caught during testing because?

      But, it was caught during testing. We bought it and tested it out and it seems to catch fire and burn, so end of story.

      Didn't you know end users are testers now?

    • Re: (Score:3, Funny)

      by sit1963nz ( 934837 )
      They were tested using Android Lollypop, its only when they installed Marshmallow that it became an issue.
    • These idiots have no idea what caused the fires. They haven't shown a single case where they can identify that the pressure on the battery causes thermal runaway. Remember that several phones failed while idle (not charging) and one failed while turned off (the guy on the plane). This "explanation" is just a couple of guys trying to Monday morning quarterback.

      • by dgatwood ( 11270 )

        Much like testing for certain medical diseases, sometimes you can only determine a cause by exclusion.

        • A phone that is turned off is consuming no power, so the failure cannot plausibly be caused by an excessive rate of discharge or by external heat (e.g. being too close to a hot GPU).
        • A phone that is not charging is adding no power to the pack, so the failure is probably not caused by an excessive rate of charge or by overcharging.
        • Multiple battery manufacturers use different battery chemistry and differen
    • Re:Interesting (Score:4, Insightful)

      by Moof123 ( 1292134 ) on Monday December 05, 2016 @07:32PM (#53428725)

      Having sat through management/engineer meetings it went like this:

      Manager: Why are you wasting 10% there?
      Engineer: We need design margin for tolerance stackup and thermal expansion.
      Manager: But we'll lose sales! (in his head: "I'll lose my bonus!")
      Engineer: We need design margin or there is a chance that some of the batteries could catch on fire.
      Manager: So only a chance? Make the battery 10% bigger and stop complaining.

      Engineers are measured and cautious in their statements. They talk in statistics, numbers, and probabilities, all of which have been lobotomized out of mid-level managers.

      • by gweihir ( 88907 )

        Engineers are also often unable to get the message across or do not even notice that it has not gotten across. As a technology consultant, this skill is about as important, if not more, than your engineering skills. I once heard a talk by a lobbyist on how to talk to politicians (a real eye-opener). The same applies here: Do not say it "could have a thermal runaway event", say "it will explode". Do not say "this could create a vulnerability", say "if you do that, somebody will attack you successfully, and i

  • Explode? (Score:5, Insightful)

    by markdavis ( 642305 ) on Monday December 05, 2016 @06:14PM (#53428163)

    >"...what may have caused some devices to overheat and explode,..."

    To my knowledge, NONE of them "exploded". Those that had actual problems had overheating which led to a fire. That is not an "explosion". That word was used by the media to stir up tons of inaccurate hype.

    >"...causing them to touch, heat up, and eventually in some cases, catch fire."

    Exactly.

  • by Waffle Iron ( 339739 ) on Monday December 05, 2016 @06:21PM (#53428207)

    If only Samsung had brought in Mr. Whipple to help educate the public.

  • Instead of being activated at users request it activates at random.

  • by Joe_Dragon ( 2206452 ) on Monday December 05, 2016 @06:27PM (#53428255)

    What about stop making stuff super thin?

    • by mlts ( 1038732 ) on Monday December 05, 2016 @06:35PM (#53428323)

      This. I have my old HTC Wizard from over ten years ago in a drawer. It isn't thin... but it had a week's battery life, and that is with the TI OMAP CPU overclocked as fast as possible.

      I'd rather have a fatter phone that has a better battery life, perhaps a slider phone, so I can use a real physical keyboard as opposed to typing and hoping autocorrect doesn't cause issues.

      Why does every phone maker want to beat Apple at Apple's game? Instead, why can't they create their own games with their own rules? There is definitely room for slider phones shaped like the Droid.

      • by Pulzar ( 81031 ) on Monday December 05, 2016 @06:55PM (#53428491)

        Why does every phone maker want to beat Apple at Apple's game? Instead, why can't they create their own games with their own rules? There is definitely room for slider phones shaped like the Droid.

        You make it sound easy to come up with a phone design that's radically different from iPhone, but also very desirable.

        Slider phones just don't sell well, and big thick phones don't sell well. So, that's not going to do it. I guess Motorola tried something with modular add-ons, but that doesn't seem to be working, either.

        Why can't they create their own game? Because it's damn hard.

        • by PsychoSlashDot ( 207849 ) on Monday December 05, 2016 @07:52PM (#53428841)

          big thick phones don't sell well.

          We don't know that. Every time there's a new chipset or screen that increases efficiency, the manufacturers reduce thickness and battery life at the same time. We stay at maybe four-hours of full-power usage. Nobody's made a phone that gets a next-generation efficient SoC but keeps its thickness and markets it as "last year this was thin enough, only now we've got 16 hours of battery life!"

        • To support your point, remember what Samsung designs looked like before the iPhone?

          Here's a photo reminder:
          http://photos2.appleinsider.co... [appleinsider.com]

    • Occasionally, it has to fit in a small portman's [yahoo.com] pocket, my good man.
    • I feel like the "tech mobile consumer electronics" industry as a whole is so far up each other's assholes they haven't bothered to ask normal people if they want phones that are thinner. Every time I search for an upcoming phone to see if I should buy it (about every 2 years) all I can find are articles written by people who sound like they masturbate using the newest version of the iphone while thinking about how many more pixels next month's iphone might have.

      Asking anyone I know IRL what phone they h
      • by wickerprints ( 1094741 ) on Monday December 05, 2016 @07:55PM (#53428859)

        The obsession with thinness is all the more ironic considering that for many of these devices, the very first thing that the user does is cradle it in a thick plastic or silicone case to protect its exquisitely sleek and fragile surface.

        I totally understand that people want to be able to protect and personalize their phones through cases, but it really proves how consumers don't actually NEED each successive generation of devices to be increasingly thinner. They want durability, they want grip, and they want better battery life, none of which is served by making devices so thin they will bend or explode with the slightest force.

        Don't make something thin unless you intend for it to also bend.

        I'm old enough to remember the "small" phone craze that happened decades ago. Mobile phones were on this progressive death spiral toward tinier and tinier form factors (this was even parodied in Zoolander). Now it's the same thing, just with thinness. It's a sign that the industry has gotten too comfortable with itself. Something will need to come along that really innovates, much in the way that the original smartphones broke the tiny phone trend.

    • Pff, whatever, if it was half a millimeter thicker, it would've ruined the entire aesthetics of the device and everyone would've just called it fatty-fat-fone. I'd rather have it exploding and burning me than walk around with fatty-fat-fone.
      Americans and have no idea what a millimeter is and will believe this. Muah ha ha ha!

  • by Harlequin80 ( 1671040 ) on Monday December 05, 2016 @06:28PM (#53428275)

    If this was the case then a slightly physically smaller battery would have solved the problem. They could have achieved this quite easily, even if it meant sacrificing capacity. And given they started by recalling the phones and replacing the batteries but there were still problems I would suggest they are wrong.

    • If this was the case then a slightly physically smaller battery would have solved the problem. They could have achieved this quite easily, even if it meant sacrificing capacity. And given they started by recalling the phones and replacing the batteries but there were still problems I would suggest they are wrong.

      Did you even look at the linked report? These engineers have the benefit of hindsight. They knew that the initial attempts to fix the problem failed; it's mentioned in the very first paragraph of the linked report. They said that sources from within Samsung had various theories as to the cause, so whatever fix that Samsung did it was the wrong theory. Just because Samsung got it wrong (twice) doesn't mean that these engineers were wrong.

      Your post mirrors what was in the second paragraph of the report:

      But,

    • You could be right. To me it sounds like both the battery design was too aggressive for current technology as well as the space allowed for the battery to do its thing was insufficient. If they replaced the battery, it would have to be less aggressive, lower capacity design plus a reduction in the battery's physical size.

      The resulting battery may have been insufficient for the phone in a way that was unacceptable to the marketing guys. If the phone only has 1 to 2 hours of power with the fix, the hit to the

      • by fnj ( 64210 )

        the battery design was too aggressive for current technology

        Battery "design"? The phone company doesn't "design" the battery. They just call up the Ching Chong Very Fine Battery Company and say "we want 10 million LiPoly state of the art batteries x by y by z mm". All the manufacturers call up the same battery company. There's nothing "special" about the batteries any of them use.

        That said, you may be right that these batteries are all ticking time bombs. We know that all models of all brands of cell phones

    • by janoc ( 699997 )

      They were replacing the faulty batteries with the same type (= same dimensions & capacity), only from a more recent batch, because the original suspicion was a battery manufacturing problem, not a design issue with the phone itself. Remember the Sony laptops catching fire few years ago because of defective batteries?

      So the conclusion is still plausible, because the replacement batteries have never fixed the underlying design issue - essentially equivalent of the iPhone's "bendgate", unfortunately with m

      • It's not Slashdot "catching wind" of this. It's the startup company Instrumental writing a blog post and shopping it around to all the tech sites to get people to go find out what the company Instrumental is and does.

        From their website http://www.instrumental.ai/ [instrumental.ai] , it looks like they sell services to companies that manufacture things.

        Their case study with Pearl Auto seems like they landed the gig because Pearl Auto is a startup run by a friend.

        And as far as I can tell the most work they actually do is put

      • This actually contributes to the theory of this story. One battery manufacturer used slightly better / thicker insulators between the layers in the battery, thus they better withstood the design flaw that resulted in excessive pressure on the battery. However that just reduced the frequency of failure, but still didn't prevent it entirely.

    • IF the manufacturer knew this was *the* cause of the problem, the only cause, and they had confidence in that assessment, then yes they could have fixed it. Or avoided it.

      Come to think of it, no matter what the cause(s) is/are, the manufacturer could have avoided the problem in the first place, if they knew all of the above. Obviously they don't magically know all these things.

    • If they got replacements with different batteries it would have created an incompatibility with the previous ones, i bet they decided against that. Also, they may have not known until too late

  • by Anonymous Coward on Monday December 05, 2016 @06:29PM (#53428279)

    Hopefully this provides some motivation to stop equating thin with better.

    Nah, who am I kidding, people are stupid.

  • by Nunya666 ( 4446709 ) on Monday December 05, 2016 @06:37PM (#53428341)
    As in most cases, going to extremes is rarely a good thing.
  • by aevan ( 903814 ) on Monday December 05, 2016 @07:03PM (#53428547)
    So it's not a design flaw, merely people have been handling them wrong. Well, all's forgiven then, we have precedent that bad gripping by users is user fault, not company. Time to dismiss this as non-news.
  • by Overzeetop ( 214511 ) on Monday December 05, 2016 @07:21PM (#53428653) Journal

    If they found the problem, it means that they can reproduce it. They were entirely unable to make their test unit fail due to the tight fit, nor were they able to observe that an increase in pressure of a phone in the off condition (under which at least one of the fires occurred in the v2 Note 7) *led to* a runaway thermal condition.

    They're basically just speculating because they are looking for some clicks. This is about as conclusive proof as Trump has of 3 million illegals voting in California.

  • The "manufacturing technology company" is a small startup with no experience, expertise, or credentials.
    Further, they had a single unit to work with. Their testing revealed nothing conclusive and they weren't able to actually discern anything.

    All they did was look at it and say it's a very tight fit. Everything else is speculation.

  • Hold it.. (Score:4, Informative)

    by XSportSeeker ( 4641865 ) on Monday December 05, 2016 @08:07PM (#53428941)

    People should bare in mind that this is at most an educated guess made by disassembling a single unit and speculating about limits of current tech battery design.
    They were not hired by Samsung, they are not an official body of investigation, and they didn't have access to anything in the design in manufacturing process.

    It's quite possible that they are right, but they are not explaining anything there, just speculating.

    Now, it'd be extremely sad if the Note 7 was killed because of such a design oversight, because quite honestly, that's borderline amateurish. It could happen, as similar problems happen in most brands. Just that Samsung made the omission in the worst component possible.

    We have examples of problems in antennas, cameras, lenses, connectors, shoddy speakers, crappy GPS chips, poor materials used in bits and pieces, among several other stuff... the difference is that if you have something wrong with battery, the consequences might not be only working poorly, ending up in glitches and whatnot. The consequence might be an explosion. Which is probably the worst thing hardware can do. :P

    Anyways, the device is as dead as it can be. Which is plenty bad, because it'd probably be a best seller otherwise. Hopefully though, the lesson is learned by all manufacturers. It simply isn't worth sacrificing battery security to make the device thinner, or to shove extra mAh in there.
    The worst part is that I can bet all you want that fans of the Note line would definitely not be bothered much with having a smaller battery or a slightly thicker phone. It's all about the stylus and screen size.

    Back to the topic, I'd wait for further investigation for a final conclusion. Disassembling a single device and taking guesses is not that much better from theories that have been thrown around so far.

  • by ctrl-alt-canc ( 977108 ) on Monday December 05, 2016 @08:12PM (#53428973)
    ...Dilbert quote [dilbert.com].
  • by sabbede ( 2678435 ) on Tuesday December 06, 2016 @08:48AM (#53431633)
    Sounds disgustingly bulky to me. I'd rather burst into flames then have that gross nonsense packing my pocket. Ick!

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