Contributed by Natalie Blazer
With a consumer base more and more inclined to “go green,” electric vehicles continue to gain popularity on the road, especially now that buyers may be eligible for a sizable federal income tax credit. Automakers, for their part, have a major incentive to increase their fleet of electric cars, given the Obama administration’s proposal to increase average fuel economy standards to 54.5 miles per gallon by 2025. Despite the tendency for consumers and manufacturers alike to join the alternative technology bandwagon, however, recent concerns about batteries catching fire days or weeks following a crash may put the brakes on electric car sales. And the batteries aren’t the only thing under fire – just last week Congress announced that it would be investigating the National Highway Traffic Safety Administration (NHTSA) itself, the agency charged with investigating the fires.
By way of background, in May of 2011 the NHTSA crashed a Chevrolet Volt in a New Car Assessment Program (NCAP) test designed to measure the vehicle’s ability to protect occupants from injury in a side collision. During the crash test, the vehicle’s lithium-ion battery was damaged and the coolant line was ruptured. Three weeks after the car was crashed, a fire occurred. The NHTSA concluded that the damage to the lithium-ion battery during the crash led to the fire.
In an effort to recreate the May test, the NHTSA conducted three tests on the Volt’s battery packs in November that intentionally damaged the battery compartment and ruptured the vehicle’s coolant line. In each test, the Volt’s battery was impacted and rotated to simulate a real-world, side-impact collision into a narrow object such as a tree or pole followed by a rollover. Two of the three crash tests resulted in fire days or weeks following the crashes.
According to GM, maker of the Chevrolet Volt, during a crash the vehicle’s coolant line ruptures and leaks onto the wiring in the battery. After a period of time, the coolant crystallizes and causes a short. GM says that the test fires could have been prevented by draining the battery after the crashes, which GM promises to send engineers to do after any real-world crash. According to GM, service personnel must also de-power the batteries after a collision, because if electrical energy is left in a battery, it’s similar to having gas in the tank of a car that has been damaged. There have been no real-world fires after any Chevrolet Volt crash, and the test fires are not linked to any flaw in battery cells supplied by South Korea’s LG Chem, according to GM.
On Nov. 25, the NHTSA released a statement announcing its “formal safety defect investigation” into the stability of Volt batteries following a crash or other significant event. While the investigation is ongoing, GM has offered Volt owners a free loaner vehicle or a buy-back of the Volt itself. GM has also stated that it is working on a battery design fix that could, depending on the results of the investigation, be retrofitted onto the 6,000 Volts on the road.
Thus far the NHTSA and GM have cooperated in the research effort to determine what causes the battery to catch fire and what can be done to fix the problem, focusing specifically on the performance, handling, storage and disposal of batteries after a crash or significant event. They are urging auto manufacturers and consumers to be aware of the proper handling of batteries following a crash or violent braking of the car. NHTSA has asked automakers that use or plan to use the batteries in their vehicles for special handling and discharging recommendations.
Although NHTSA testing thus far has not raised safety concerns about electric vehicles other than the Volt, GM says this is not just a Volt issue. To that end, GM has formed a joint electric vehicle initiative with the Society of Automotive Engineers and other auto companies to address new issues relating to batteries, and the initiative will focus on all electric vehicles, not just the Volt.
Meanwhile, the House Committee on Oversight and Government Reform announced last week that it was investigating the NHTSA after it “deliberately suppressed public knowledge” related to these very safety risks posed by the Chevrolet Volt. According to a December 7 letter from Rep. Darrell E. Issa (R-Calif.) and other committee Republicans, the agency failed on several occasions to publicly disclose safety issues related to the Volt’s battery system while its formal investigation into the fire risk was ongoing. The committee claims the NHTSA knew of the problem when it first conducted the crash tests in May but did not disclose its knowledge until November. The committee further states that there is an overall lack of public documents on the issue and that the NHTSA gave the Volt a five-star safety rating while it was looking into the safety of the vehicles, a fact of particular concern to the committee.
The Volt inquiry is part of a broader effort launched by the committee for the purpose of investigating fuel economy standards being crafted by the NHTSA and the Environmental Protection Agency (EPA). The larger investigation is focused on the Obama Administration’s proposal to increase fuel economy standards, and since the proposed regulations rely heavily on the commercial deployment of electric vehicle technology, the safety of lithium-ion batteries used in such vehicles is of paramount interest.
This safety issue should be monitored carefully by car makers, battery manufacturers, service personnel and consumers alike. Given that there have been no real-world fires or injuries to date, electric vehicles should continue to be a viable option to cut down on fuel emissions, assuming all proper safety precautions are taken. After all, as many industry observers are quick to point out, gas automobiles did not gain traction without several valuable lessons being learned in the process. Similarly, it seems unlikely that issues with lithium-ion batteries will hinder the advance of alternative technology vehicles, although we won’t know for sure until the investigations are complete.