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Engineers Explain Why the Galaxy Note 7 Caught Fire (digitaltrends.com)
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.
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.
TANSTAAFL
Software "engineers" at best.
This is the company in question. https://www.instrumental.ai/te...
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.
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.
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
In a time of universal deceit, telling the truth is a revolutionary act. George Orwell
On the other hand, you have EEs like me.
Engineering runs a spectrum. From near cookbook, long practiced, design processes owned by PEs to prototypes hacked up with three opamps, a FPGA, a breadboard and a coat hanger.
Design of consumer product batteries is 'near cookbook long practiced'.
Even I could do it. Samsung wouldn't have given me the authority to tell the PHB they _needed_ volume Y for X mWh. I guarantee there was an Engineer or ten that knew this was a bad idea, but couldn't penetrate the layers of management between him and the person dictating required features.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'