Samsung has officially revealed the cause for the Galaxy Note 7’s battery explosions. The faulty batteries came from the company’s own subsidiary SDI. Samsung SDI is reported to have supplied around 70 percent of batteries used in the Galaxy Note 7.

Samsung wrote on its UK website, “Based on our investigation, we learned that there was an issue with the battery cell. An overheating of the battery cell occurred when the anode-to-cathode came into contact which is a very rare manufacturing process error.”

The company also added that this is not a device issue. The issue is isolated to the battery cell only. It added, “For customers who already have Galaxy Note7 devices, we will voluntarily replace their current device with a new one over the coming weeks.”

Globally, as of September 1, there have been 35 cases that have been reported through Samsung’s customer service centers. Korea reported 17 cases, US reported 17 cases, and 1 case from Taiwan was reported. The company does not expect the incident rate to grow.

Recently, a hotel room was damaged after a Samsung Galaxy Note 7 exploded in Australia. An Australian man was left with burns and billed more than 1800 dollars after he reportedly claimed that his new branded Samsung Note 7 exploded while he was asleep at a hotel room in Perth. The explosion charred the hotel room, bed sheet and the carpet. One of my finger was also burned when I threw the handset to the floor, Tham Hua, from Victoria state, said. "My brand new Note 7 exploded this morning while I was still asleep, it was plugged in an original Samsung charger," he was quoted as saying by local publication The Australian.

The US aviation safety officials has also taken the extraordinary step of warning airline passengers not to turn on or charge a new-model Samsung smartphone during flights following numerous reports of the devices catching fire. The Federal Aviation Administration also warned passengers not to put the Galaxy Note 7 phones in their checked bags, citing "recent incidents and concerns raised by Samsung" about the devices. It is extremely unusual for the FAA to warn passengers about a specific product.