The lawsuit, filed in U.S. district court, alleges the house fire was the direct result of the iPhone's battery short-circuiting and heating up. Thao nor anyone else ever changed the battery in the iPhone, according to the complaint.
On or about April 1, 2016, the iPhone failed, starting a fire in Thao's home. Preliminary investigations show evidence of a significant and localized heating event in the battery area of the iPhone as well as remnants of internal shorting, indicating that an internal failure of the iPhone's battery caused the fire.The complaint reiterates that the design, manufacture, and sale of the iPhone 4s created a "dangerous, unsafe, and defective" condition.
If designed improperly, lithium-ion batteries do have the potential of short-circuiting and catching fire, as Samsung learned the hard way with its recalled Galaxy Note7 last year. But, that hasn't been a widespread issue with the iPhone 4s since it launched in 2011, so this is certainly an isolated incident.
Thao and State Farm are seeking at least $75,000 in damages from Apple, but the exact amount is to be determined if and when the case is heard.