The report said the car's lithium-ion battery case was damaged, and in the ensuing fire the infotainment system's onboard storage device was destroyed.
However, the "restraint control module," which stores data such as whether seatbelts were in use, how fast the vehicle was going, acceleration information, and airbag deployment, although damaged by fire was recovered and turned over to the NTSB's laboratory to evaluate.
Why an experiment? Isn't there a Black Box, like on aeroplanes, with logs to definitively answer the question?