In a new report, The Wall Street Journal says that Samsung’s official investigation into the Galaxy Note 7 fires has discovered that irregularly-sized batteries and a manufacturing issue are responsible. Samsung has declined to comment on the report and is holding an event on Sunday night (EST) to reveal its findings.
The report says that the initial problem came with batteries from Samsung SDI, which were irregularly-sized and didn’t fit properly into the tight parameters of the Note 7. This improper fit led to issues with overheating and subsequent fires.
After Samsung stopped production of batteries from Samsung SDI, it increased production of batteries at Amperex Technology Ltd, a Hong Kong-based manufacturer whose batteries had no record of overheating. However, an undisclosed manufacturing issue arose in the rapid increase in production, leading to further overheating in new batteries from ATL. This issue resulted in Samsung cancelling production of the Galaxy Note 7 and recalling all devices.
Though this report hasn’t yet been confirmed by Samsung, it seems highly plausible, and lines up with a previous third-party finding from Instrumental, which proposed that the overheating issues were caused by a tight design that compressed batteries.
Stay tuned for more coverage as Samsung prepares to officially announce the results of its investigation.