Firefighters incinerated Tesla's X-type battery pack, and the
company's engineers removed about a quarter of the power battery before
the vehicle was thought to be safely off the California highway.
This
does not prevent the re-ignition of powerful and flammable lithium-ion
battery cells. According to a safety bulletin from the Mountain View
Fire Department, the car re-emerged within 24 hours of the fatal
accident on March 23 and after 6 days.
On March 23, emergency rescuers at the site of the Tesla crash on US Highway 101 in Mountain View, California, USA.
The
fire of electric vehicles is rare, but as automakers prepare to
increase production significantly, the volatile chemical composition of
the battery and the special training needs of how to extinguish it have
created new safety issues. The technology of vehicles that burn gasoline
fuel may make battery-powered vehicles even worse.
Donald
Stoy, a professor of materials chemistry at the Massachusetts Institute
of Technology, said: "We are here in unknown waters." "When you start
packing a 70-kilowatt battery in a car, it's completely different from
what happens in a cell phone."
Lithium batteries are
becoming more and more popular, and various power sources, from personal
electronic products to bicycles, are affected by fire explosions. In
one of the world's most advanced jets, the Boeing 787's e-cigarettes,
laptops and even battery packs, e-cigarettes have triggered government
restrictions and terrible headlines.
The National
Transportation Safety Board has investigated two recent Tesla fires and a
fire last year. The National Highway Traffic Safety Administration,
which is responsible for setting vehicle safety standards, announced on
Thursday that it also collected information on the latest episode at
Fort Lauderdale, Florida on May 8. Swissspecial also checked the deadly
Tesla crash last week and caused a fire.
Earlier: General Motors said after the ambush fire, prompted lithium battery detector
This
issue is not new. The National Highway Traffic Safety Administration
has previously evaluated battery fires, including General Motors'
Chevrolet Volt, which fired in 2011 and crashed the vehicle several
weeks later. Manufacturers of other car-induced fires include former
Fisker and Mitsubishi Motors.
The components of a lithium ion rechargeable battery make it inherently prone to fire.
Unlike
gasoline, which requires ignition before ignition, lithium batteries
contain their own ignition system: a large amount of energy that turns
into heat and spark when they are shorted. They also contain powerful
fuel solvents and oxidized metals that supply oxygen to the flame,
complicating efforts to extinguish.
Related: Security agencies are looking for a deadly Tesla crash, a Florida fire
"This
is a long-standing problem with lithium-ion batteries," said Prashant
Kumta, a professor of engineering in battery chemistry at the University
of Pittsburgh.
Kumta said that while the battery industry
has made great strides in ensuring that batteries operate safely during
normal operation and charging, the battery industry is almost
impossible to complete once the battery is torn apart in a violent
collision. He said that in a phenomenon called thermal runaway,
short-circuiting the battery generates more heat, causing a chain
reaction of the fire and generating more heat in the adjacent battery.
"It's
basically like a hot cracker," he said. "You have a battery that will
catch fire, then the next battery will catch fire, and soon they will
catch fire."
Comparative risk
According to
the latest data from the National Fire Protection Association, in 2015,
174,000 fires occurred in all cars in the United States, killing 445
people.
The car manufacturer spoke highly of the concern
of the Tesla fire over a few car fires. In a 2013 blog post, company
president Elon Musk said that the risk of a gasoline-powered car on fire
was more than four times higher than the Bitsla ModelS.
“In
your life, you are more likely to be struck by lightning, even more
than in a non-harmful fire in Tesla,” Musk said. The company did not
respond to recent requests for comment.
At the 2011 press
conference, the Chevrolet Volt fire triggered the NHTSA's statement that
it does not consider electric cars to be more susceptible to flame than
other cars.
Previous: GM development methods deal with battery cells after a crash
After
this, NHTSA conducted a series of tests on the Volt battery pack.
According to the agency's report, two types of batteries were on fire in
six types of accident simulations. At the time, the search for crash
records did not reveal evidence of other fires.
However,
there is very little government data on the occurrence of electric
vehicle fires, so it is difficult to document the severity of the
problem, said Jason Levine, executive director of the Automotive Safety
Center advocacy organization.
“One of the few disturbing
things about these fires is the real lack of available, quantifiable
data that can help everyone,” Levin said.
It is not only
difficult to compare electric vehicles and gasoline-powered vehicles,
but it is also difficult to compare the possibility and severity of
fires between Tesla and other lithium-ion battery vehicles such as
Chevrolet bolts and Nissan Motors. Levin said that his leaves and the
BMW i3.
An indisputable fact is the intensity of fire in large lithium-ion battery packs like fireworks.
According
to the video footage, on November 3, 2016, firefighters in Indianapolis
encountered a firefighter-like firefighter in a high-speed crash of a
model S striking trees and buildings, as the battery pack exploded and
fired into the air news staff. The car accident killed two people in the
car.
According to thespecial, two young people were
killed and one third injured in a crash in Fort Lauderdale, Tesla, when
the car hit a concrete wall and a fire broke out. The video on the scene
showed that the S-type fire was engulfed.
“The
NTSB has a long history of investigating emerging transportation
technologies, such as lithium-ion battery fires in commercialspecial,”
NTSB Chairman Robert Sumwalt announced in a statement that the agency
is investigating.
When the X-type car in the Mountain View
hits the side of the concrete highway barrier, the front of the car is
cut, damaging the battery pack under the floor. Juan Diaz said that
about half of the cars were on fire when the staff arrived. He added
that it took about two minutes to extinguish the flame.
Driver Walter Huang was killed.
The
person in charge said that Mountain View is located in Silicon Valley,
and electric vehicles are common. Firefighters received battery fire
training at the Fremont plant near Tesla in 2014. Nonetheless, the case
also suggests that the fire department may need to train more on the
unique issues caused by battery fires.
According to Diaz and the site photos, firefighters use water mixed with chemicals to make foam to eliminate gasoline fires.
However,
the National Fire Protection Association does not recommend the use of
foam. The NFPA guidelines require the use of large amounts of pure water
in battery fires, up to thousands of gallons. Water helps to cool the
battery, which is the key to a ceasefire.
Worried that the
battery continues to heat up and is concerned about the risk of
electric shock, firefighters call Tesla engineers – if the location of
the accident is not near the company's factory, then this may not be
possible. Diaz said they removed about 25% of the battery cells.
Diaz
said that the firefighters accompanied the trailer to take the car to a
rescue site as the battery continued to flow and sizzled due to the gas
emitted by the battery pack. The trip did not reignite, but two more
fires occurred within the next 24 hours and a fire broke out again six
days later, Diaz said.
He said that a crew member had to discharge the remaining amount of any electricity bill before he was safe.
Scientists
are investigating promising lithium-ion battery formulations to reduce
the likelihood of fire, and there may be ways to make the battery pack
more impact-resistant. John Warner is the chairman of the National
Association of Advanced Technology Battery Nationals, the trade group.
But before that, firefighters and other emergency workers needed more education, Warner said.
“This
is a relatively new technology that firefighters have dealt with in the
past,” he said. “I think I have done some very good work. Has it
arrived at every fire department in the US? I am not sure about it.”
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