Galaxy Note 7 broke basic engineering rules, says damning new report

A teardown of the Galaxy Note 7 may have provided insight into why the infamous smartphone was prone to explosions, causing Samsung to recall and eventually cancel the device entirely. While it’s obvious the battery was a key reason for the device’s failure, a damning new report from a third-party shows what may be the underlying cause.

After acquiring a Galaxy Note 7 — no easy feat once the phones were recalled — engineers with manufacturing technology company Instrumental stripped the phone down to see what was going on inside (and yes, they had a fire extinguisher nearby, just in case). 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.

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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.