The National Highway Traffic Safety Administration also said it was satisfied with a plan by General Motors to address problems that triggered fires in the Volt after the vehicles were crash tested.
The National Highway Traffic Safety Administration posted its defect investigations results late Friday saying the investigation, which opened Nov. 25, is now officially closed.
NHTSA released a statement, analysis of its battery testing, fire incident reports and guidance for emergency responders late Friday in announcing the conclusion of its investigation.
The statement read: “The agency’s investigation has concluded that no discernible defect trend exists and that the vehicle modifications recently developed by General Motors reduce the potential for battery intrusion resulting from side impacts.
“Based on the available data, NHTSA does not believe that Chevy Volts or other electric vehicles pose a greater risk of fire than gasoline-powered vehicles,” NHTSA said, noting all vehicles have some risk of fire in the event of a serious crash.
NHTSA believes General Motors’ efforts to retrofit Volts in dealerships and on the assembly line addresses safety concerns. The Hamtramck plant has been on an extended holiday shutdown but will resume production Feb. 1, said GM spokesman Greg Martin.
GM spokesman Greg Martin said of the NHTSA announcement: “NHTSA’s decision to close their investigation is consistent with the results of our internal testing and assessment.
“The engineering enhancements that GM announced Jan. 5, 2012 will provide additional protection for the battery minimizing the risk of a post-crash fire in the days and weeks after a severe crash and rollover.”
The modifications include extra steel around the battery pack to prevent vehicle parts from puncturing the battery case in severe crashes. Leaking coolant contributed to electrical fires in two Volt batteries that were sitting for a t least a week after government crash tests.
GM also is adding a sensor to monitor coolant levels and will attach a bracket to keep the coolant tank from leaking.
A Dec. 22 government crash test – after the changes were made to the car — did not cause intrusion into the battery case and the coolant did not leak. Those are the two events that can combine to cause a fire. NHTSA monitored the Volt for weeks afterward and the car was fine.
No Volts on the road have caught fire.
GM sold 7,671 Volts in 2011, including 1,529 in December, which was also a strong month for fleet sales.
NHTSA statement on conclusion of Chevy Volt investigation
WASHINGTON, DC – The National Highway Traffic Safety Administration (NHTSA) released the following statement today regarding the conclusion of its safety defect investigation into the post-crash fire risk of Chevy Volts (PE11037):
Today, the National Highway Traffic Safety Administration closed its safety defect investigation into the potential risk of fire in Chevy Volts that have been involved in a serious crash. Opened on November 25, the agency’s investigation has concluded that no discernible defect trend exists and that the vehicle modifications recently developed by General Motors reduce the potential for battery intrusion resulting from side impacts.
NHTSA remains unaware of any real-world crashes that have resulted in a battery-related fire involving the Chevy Volt or any other electric vehicle. NHTSA continues to believe that electric vehicles show great promise as a safe and fuel-efficient option for American drivers. However, as the reports released in conjunction with the closure of the investigation today indicate, fires following NHTSA crash tests of the vehicle and its battery components—and the innovative nature of this emerging technology—led the agency to take the unusual step of opening a safety defect investigation in the absence of data from real-world incidents.
Based on the available data, NHTSA does not believe that Chevy Volts or other electric vehicles pose a greater risk of fire than gasoline-powered vehicles. Generally all vehicles have some risk of fire in the event of a serious crash. However, electric vehicles have specific attributes that should be made clear to consumers, the emergency response community, and tow truck operators and storage facilities. Recognizing these considerations, NHTSA has developed interim guidance—with the assistance of the National Fire Protection Association, the Department of Energy, and others—to increase awareness and identify appropriate safety measures for these groups. The agency expects this guidance will help inform the ongoing work by NFPA, DOE, and vehicle manufacturers to educate the emergency response community, law enforcement officers, and others about electric vehicles.