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One of the biggest mysteries of 2016 will come to an end sometime this month. Samsung will make public the results of its months-long investigation into what caused several Galaxy Note 7 smartphones to turn into flames later this month, according to a report on Reuters. From the report: The South Korean firm said in October it was examining all aspects of the phone, suggesting there may be a combination of factors that contributed to one of the costliest product safety failures in tech history. Samsung has also previously noted that it was working with several third-party sources and experts to figure out what could have caused the error. A popular theory among many is that Samsung attempted to further slim the form factor of the Galaxy Note 7, which resulted in the battery to be held too tightly within the device -- which in turn, caused the layers of lithium cobalt oxide and graphite to touch.

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.