Volt is the world’s most popular plug-in hybrid until competitive vehicles arrive later this year.
The National Highway Traffic Safety Administration today closed its safety defect investigation about the risk of fires in Chevrolet Volt EVs without a recall. There was a concern that the Volt’s battery pack could ignite after a serious crash. NHTSA concluded that “no discernible defect trend” exists and that Volt modifications developed by General Motors reduce the potential for battery intrusion and fires resulting from severe side impacts.
NHTSA also said it remains unaware of any real-world crashes that have resulted in a battery-related fire involving the Chevy Volt or any other electric vehicle. The world’s most prominent auto safety agency set a precedent back in November by opening a safety defect investigation without any supporting data from real-world incidents.
The Volt investigation concludes during the same week that the National Research Council agreed with NHTSA’s conclusion that electronic throttle control systems (ETCs) were not a plausible cause of Toyota’s unintended acceleration problem.
However, NRC remains worried about the safety agency’s competence in automotive electronics. In the Toyota safety defect investigation NHTSA said that Toyota unintended acceleration was caused by drivers pressing the gas pedal by mistake, as well as accelerator pedals sticking or becoming entrapped by floormats. Ultimately this led to huge Toyota and Lexus recalls and subsequent record fines for Toyota’s cover-up of the deadly defect, but not until NHTSA was severely criticized for its lack of action during Congressional hearings on the Toyota matter.
Concerning Toyota, NRC said “However, it is ‘troubling’ that NHTSA could not convincingly address public concerns about the safety of automotive electronics. Relative to the newer electronics systems being deployed and developed, ETCs are simple and mature technologies. To respond effectively and confidently to claims of defects in the more complex electronic systems, both in present-day and future vehicles, NHTSA will require additional specialized technical expertise.”
NHTSA opened its Preliminary Evaluation on 25 November following a severe-impact lab test on a battery pack that resulted in an electrical fire six days later. The test was conducted to reproduce a coolant leak that occurred in a full-scale vehicle crash test last May that resulted in an electrical fire three weeks later.
In a statement immediately released after NHTSA closed the Volt fire investigation, General Motors said: “The National Highway Traffic Safety Administration’s decision to close its investigation is consistent with the results of our internal testing and assessment.”
In early January GM announced customer satisfaction modifications to the Volt to reduce the possibility of an electrical fire occurring after a severe side impact crash. GM is strengthening the Volt’s vehicle structure, putting a sensor in the reservoir of the battery coolant system to monitor levels, and adding a tamper-resistant bracket to the top of the battery coolant reservoir to help prevent potential coolant overfill. The coolant can cause short circuits in the Volt’s lithium ion battery pack if it leaks into the cells.
Technically GM has not recalled the Volt, but EVs reputation and GM’s remain damaged with unknown effects on future sales of vehicles that use emerging technologies. NHTSA also said the agency reserves the right to take additional action if warranted by new circumstances.
See also:
- GM Will Lend Cars to Concerned Chevrolet Volt Owners as NHTSA Volt Battery Fire Investigation Continues
- Chevrolet Volt Earns 5 Stars in Euro NCAP with No Battery Fires. GM Announces Volt Export Plans to China Next Year
- NHTSA Opens a Formal Defect Investigation into Chevrolet Volt Battery Fires When a Second Fire Occurs After a Crash Test
