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According to unverified report from Reuters the cause of the Note 7 explosions, might be some breathing space problem for the batteries.
Yes, the batteries from its sister company (SDI) could be the culprit.
Meanwhile, an independent group suggested that the issue was with the design of the phone. They claim that Samsung didn’t give the battery enough room to swell as it charged and discharged and that the clearances around the battery were too slim.
The second explanation sounds reasonable, considering that Samsung is still going to use SDI batteries for the Galaxy S8.
Whatever it is, we would have to wait until the 23rd of January to find out from Samsung directly.