An investigation into the Note7 fiasco has found that its batteries were a fire hazard due to poor manufacturing.
(CCM) — Samsung has finally opened the chest on its investigation into its infamous exploding Galaxy Note7 device and revealed the causes of the spontaneous combustion episodes. Dong-jin Koh, Samung's head of mobile business, revealed in a press conference on Tuesday that two different manufacturing defects in its batteries were the causes of the explosions, Tech Times reports. Seven hundred Samsung engineers examined 200,000 Note7 devices and 30,000 of the device's batteries to produce the report. The company also received input from external investigators from TUV Rheinland, Exponent, and UL, according to the report.
Samsung's investigation discovered that the original batch of Note7 batteries, which were made by Samsung, had defects in the upper right hand corner and negative electrodes that were positioned incorrectly. This increased the changes of the negative and positive layers of the batteries touching, causing a short circuit and — in some cases — a rapid release of energy in the form of an explosion. The replacement batteries made by Amperex used in the supposedly-safe replacement Note7 devices had traces of copper near the negative electrodes due to poor welding, although it is not clear if this was caused by rushed manufacturing to produce the replacement phones. This defect also had the effect of increasing the risk that two layers of the battery would touch, causing a short circuit.
Image: © Samsung.