The Volt Fires You Never Heard About
By Bill Moore
Posted: 29 Dec 2011
Last May, the National Traffic Highway Safety Administration crash tested a series of Chevrolet Volts. The cars were slammed into barriers or struck broadside to simulate highway accidents in an effort to see what, if any, physical harm would be suffered by passengers. When the tests were completed, NHTSA gave the Volt their highest safety rating.
The damaged test cars, which would be considered "totaled" by any insurance company, were hauled off and put in shortage, one of them stacked upside-down on its roof. Three weeks later, the car caught fire in the storage facility, destroying itself and an unspecified number of other vehicles. None of the other crashed Volts caught fire, which gave researchers the opportunity to investigate the cause of the first fire, which they did in mid-November.
But four months before the NHTSA crash tests, three other Volts were also smashed to oblivion; and those are the fires we never heard about. The organization doing its own set of crash tests in February 2011 was the Insurance Institute for Highway Safety.
Early in 2011, IIHS acquired three Chevrolet Volts from GM and conducted its own series of collision tests: front impact, side impact, and roof crush. Again, all three cars were totaled. No one was going to get in these cars and drive away in them, much less park them in their garages. The only way these car would move would be on the back of a tow truck.
What differentiates IIHS's tests from NHTSAs is that the battery compartment was never breached. None of the cars caught fire. In fact, one of the Volts has been on public display at the IIHS in Arlington, Va since July.
I decided to call Russ Rader, IIHS's Communications VP after I noticed that Institutes's name on the side impact sled in the above photograph. Why, I asked him, hadn't we heard about their fires?
The reason, he explained, is because there weren't any. As part of their crash test procedure, the Institute drains each crash test vehicle's fuel tank, replacing its volatile gasoline with a inflammable fuel simulant. Like NHTSA, their technicians did not discharge the car's 16kWh battery pack. All three cars were tested with energized batteries; the aim being, of course, to see what would happen. Remember, this is weeks before the ill-fated NHTSA test in Michigan.
Because the battery compartment hadn't been compromised nor the coolant line ruptured, the cars remained essentially inert for months in storage. It was only in July 2011, when IIHS wanted to put one of the cars on display, that GM sent a technician to discharge the battery. Today, December 29, 2011, that car sits on display across the Potomac River from the nation's capital in Arlington where anyone can see it, including those pent on using the Volt fires as a political cudgel, including certain Republican presidential candidates and conservative commentators.
Mr. Rader told me that the IIHS has not withdrawn its safety rating on the Volt and emphasized "we have no concerns about the safety of the car. It continues to carry our 'Top Safety' recommendation."
And what about the remaining Volts in NHTSA's possession? In November they retrieved three of the cars and subjected them to further abuse. Here is the relevant portion of their press released:
In an effort to recreate the May test, NHTSA conducted three tests last week on the Volt's lithium-ion battery packs that intentionally damaged the battery compartment and ruptured the vehicle's coolant line. Following a test on November 16 that did not result in a fire, a temporary increase in temperature was recorded in a test on November 17. During the test conducted on November 18 using similar protocols, the battery pack was rotated within hours after it was impacted and began to smoke and emit sparks shortly after rotation to 180 degrees. NHTSA's forensic analysis of the November 18 fire incident is continuing this week. Yesterday, the battery pack that was tested on November 17 and that had been continually monitored since the test caught fire at the testing facility.
In a nutshell, NHTSA took three of the crashed vehicles from the May tests out of storage where they had been siting quietly not catching fire. They smashed them again, this time hard enough to breach the battery compartment and rupture the coolant line. They then rotated the cars 180 degrees on their tops. Nothing happened to the first car. The second car showed a brief temperature increase, but no fire occurred until some days later. The third car sat several hours and when it was rotated, it began to smoke and emit sparks, presumably due to short circuiting in the battery pack.
Note that in none of these cases was there an immediate fire, unlike what you'd find with a gasoline-powered vehicle where fuel has been spilled and vaporized. The thermal events occurred hours, days and in the one case, weeks after the crash. While NHTSA urges first responders to exercise caution in dealing with any wrecked electric car, the agency also noted that it "is not aware of any roadway crashes that have resulted in battery-related fires in Chevy Volts or other vehicles powered by lithium-ion batteries." Prudently, NHTSA has opened a "safety defect" investigation of the car, adding, however that "Chevy Volt owners whose vehicles have not been in a serious crash do not have reason for concern."
The take away from this would appear to be that unless your Volt is totaled, enough so that the battery enclosure is breached -- that would be a very, very bad accident that probably results in fatalities -- and the coolant line ruptured, neither you nor your passengers have anything to fear from a battery-initiated fire. The people who should be concerned are probably tow truck operators and vehicle salvage companies. They need to make sure the battery pack is discharged before moving the car very far or begin parting it out.
NHTSA concludes by stating that it "continues to believe that electric vehicles have incredible potential to save consumers money at the pump, help protect the environment, create jobs, and strengthen national security by reducing our dependence on oil. In fact, NHTSA testing on electric vehicles to date has not raised safety concerns about vehicles other than the Chevy Volt."
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