https://www.theverge.com/2017/10/6/16437790/iphone-8-swollen-battery-issue-apple-investigating

Apple seems to have an iPhone 8 battery problem on its hands, and it’s not clear yet whether it’s occurring in just a handful of edge cases or in a larger batch of phones.

Over the past week, reports have been coming out about iPhone 8s that have split apart either on arrival or after several days of use. What appears to be happening is that the battery inside the phone is swelling, bending the front of the phone and separating it from the body of the device. So far, there haven’t been any fires — just ruined phones.