swollen battery? Problem with iphone 8 plus back glass

[MysterySteryEry]

Hello I bought my iphone 8 plus on premier date all time my phone was in case when I taked off case I see the frame in glass i broken? and there is dust everywhere but on the other side the frame look great Someone said I have swollen battery Can someone help me?
Photos:
https://imgur.com/4VJBgoL
https://imgur.com/k1dknLr
https://imgur.com/4eNErdF

 

[JPack]

It's unlikely to be the battery because it's on the wrong side of the phone. The battery on the same side as the volume buttons. Also, the mid-frame of the phone prevents swollen batteries from expanding through the back.

 

[MysterySteryEry]

It's unlikely to be the battery because it's on the wrong side of the phone. The battery on the same side as the volume buttons. Also, the mid-frame of the phone prevents swollen batteries from expanding through the back.

Okay thanks butyou do not know how it could happen?

 

[chscag]

Looking at the images you posted, it does appear that battery swelling caused the crack in the glass frame. If the phone had been dropped or hit hard the glass would be cracked differently. Since you had it in a case I can't think of anything else that could cause the frame to separate like that.