The company says that its preliminary findings reveal that there was a manufacturing flaw which placed pressure on plates inside the battery cells. This is what caused the negative and positive poles in the battery to come into contact and trigger excessive heat which ends up burning the device itself. Samsung says that it continues to investigate this battery issue with its battery manufacturers and that it's going to carry out thorough analysis to find out “the exact cause” of this issue.
Samsung SDI is widely believed to have supplied these faulty batteries for the Galaxy Note 7. Recent reports suggest that Samsung will now be sourcing batteries for the Galaxy Note 7 from China's ATL exclusively, at least until such time when battery cells created by its battery-making division for the Galaxy Note 7 are not a fire hazard.
Update: A recent Bloomberg report reveals the following about the Galaxy Note 7's penchant for overheating and burning:
“The batteries failed because a separator within the cells was too thin and electrodes weren’t properly insulated, according to a government quality inspection agency in China.” Once again, Samsung SDI has been named as the supplier responsible for this debacle.
