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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.
This is bad. Very bad. If substantiated, the lawsuits against Samsung are going to be epic.
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.
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.
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.
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.
People perceive high-density products as high-quality, and low-density products as cheap plastic crap. Numerous products have included weights for this reason... take a look inside your mouse. People want their phones and laptops to be light so they don't have a brick in their pocket or backpack. Light * high density = low volume. They don't want to reduce the screen size, and bezels are already minimized, so the only option to reduce volume is to make it thin. Of course, once they make it thinner the advertising department will hype that feature, but the real driver is density.