A driver who died in a fiery car crash on Highway 101 has been identified by the Santa Clara County medical examiner's office.
San Mateo resident Wei Huang, 38, died of his injuries on Friday afternoon after his Tesla collided with a median at freeway speeds, triggering a three-vehicle accident and causing the car to catch fire.
The crash occurred around 9:30 a.m., when the Tesla Model S struck the barrier separating the Highway 85 carpool flyover lane from southbound Highway 101, according to California Highway Patrol officials. The Tesla careened into two lanes of Highway 101, where it was struck by a Mazda and then an Audi. Huang was transported to Stanford Hospital, where he died of his injuries.
Emergency fire crews arrived at the crash shortly after 9:30 a.m., and found that the front end of the Tesla had "substantial damage," exposing the vehicle's lithium ion battery and causing it to catch fire, according to Mountain View Police Chief Juan Diaz. Electric vehicle fires are typically put out by blasting a large quantity of water -- 3,000 gallons -- directly on the battery to bring down the temperature of the cells, which can overheat and reach temperatures of up to 900 degrees, he said.
Diaz said the department was put in a difficult situation. Fire crews had 500 gallons of water at the scene, but getting any more would have required running 2,000 feet of thick fire hose across Highway 101, which would have been catastrophic for traffic in both directions, Diaz said. But letting the car continue to burn on a busy highway, destroying the battery, would have been a bad choice as well, he said.
"In the middle of the Highway 101 freeway, that's not something we want to do," he said. "And it's not good for the environment with the byproducts of combustion."
Fire crews used the available supply of water and contacted the manufacturer of the vehicle, Palo Alto-based Tesla, to assist in getting the battery's temperature under control. Diaz said the engineers essentially disassembled a portion of the car battery on the spot, and that subsequent thermal imaging showed that the battery was no longer unstable.
Fire engines escorted the tow truck that removed the Tesla all the way to the impound yard out of an abundance of caution, Diaz said. Car batteries are capable of reigniting for 24 hours after cooling.
The challenging situation was made worse by the significant damage caused by collision itself. Diaz said that Tesla vehicles are built to be very safe, with features to help first responders deal with lithium ion batteries that ignite, but in this case emergency crews had no access to the battery's disconnect wires because they were destroyed on impact. This is the first time the department has dealt with this kind of problem, Diaz said, and he commended his department's response to the dangerous situation.