Issues that lead to the permanent discontinuation of the Samsung Galaxy Note 7 have long been linked to its battery. However, a new report from the teardown publication Instrumental has concluded the Galaxy Note 7 battery was in fact too large for its chassis. A rapid development cycle and a push for innovation ultimately led to the missteps that caused several Galaxy Note 7 handsets to spontaneously explode.
There was nothing fundamentally wrong with the 3,500mAh batteries used in Galaxy Note 7 handsets. However, the compartment for the cell was as deep was the battery was thick, at 5.2 mm, making for a tight fit, according to Instrumental. Furthermore, there was little room left within the Galaxy Note 7 to accommodate the natural expansion of batteries over time. The space between the battery compartment’s X and Y axes and the rest of the handset were as 0.1 mm and 0.5 mm respectively.
The blog noted Samsung should have left at least an extra 0.5 mm of space around the battery compartment to allow the cell to expand with use. It is possible even if the Galaxy Note 7 did not suffer from spontaneous explosions, battery expansion would have caused the handsets to break apart over time.
Instrumental described the Galaxy Note 7 battery as a “flattened “jelly-roll” consisting of a positive layer made of lithium cobalt oxide, a negative layer made of graphite, and two electrolyte-soaked separator layers made of polymer. The positive and negative layers in the battery are never to touch because of volatile reactions that could occur. However, the pressure under which the Galaxy Note 7 battery was housed caused these layers to come too close together and lead to handset explosions.
The Galaxy Note 7 notably has a smaller battery than Galaxy S7 Edge, which houses a 3,600mAh battery. The early-year Samsung smartphone, which has not suffered from extensive explosions has a similar design to the Galaxy Note 7, while still being a smaller device. However, Samsung representatives told iDigitalTimes prior to the Galaxy Note 7 launch that the device’s battery was made smaller to make room for the signature S-Pen stylus.
Several other investigations have come to similar conclusions. Bloomberg reported in October that the component sizing issues within the Galaxy Note 7 caused volatile reactions within the battery. The Wall Street Journal claimed that a rush to beat Apple’s iPhone 7 to market prompted Samsung to introduce a more rapid development cycle, which may have caused the company’s engineers to overlook design flaws in the smartphone.
Samsung recently stated it will release the conclusion from its own internal investigation by the end of the year, according to the Korea Herald.
