Well This is According to a Nigerian Guy Marcelliot who shared the story on Nairaland;
My power bank drains rapidly. Charging it takes up to 6 hours, but reverse is the case when using it. Doesn’t even last up to an hour.
So I decided to open it. Alas! What I saw was alarming.I opened it and saw four blue-coated cells. Two was connected, but the other two wasn’t.
Worried why the other two wasn’t connected, so I took one and broke the blue-coat, then opened it.
Alas! The cell was filled with sands.Pics below.