Battery issue no doubt...
Posting without reading?
At Heathrow, television footage showed damage to the top of the jet's body near the passenger doors at the rear of the 787. That area of the aircraft houses the crew rest compartment, which sits above the passenger cabin. The 787's twin lithium-ion batteries are installed below the floor in electrical bays near the nose and between the wings of the aircraft, far from the damaged area visible in the footage.