Investigations

Post-Crash EV Fire Hazard

NHTSA Preliminary Evaluation PE11037 - closed, opened 2011-11-25.

PE11037 Preliminary Evaluation Closed

NHTSA investigation PE11037 is a Preliminary Evaluation opened on 2011-11-25 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2012-01-20 - NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.

A Preliminary Evaluation like PE11037 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.

Investigators summarized the matter as follows: "The subject vehicles, which employ emerging technology, are range-extended electric vehicles that utilize a high voltage (HV) battery to provide energy for propulsion. The HV battery is lithium-ion based technology that..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time.

Status
Closed
Type
Preliminary Evaluation
Opened
2011-11-25
Latest Activity
2012-01-20

Investigation Summary

The subject vehicles, which employ emerging technology, are range-extended electric vehicles that utilize a high voltage (HV) battery to provide energy for propulsion. The HV battery is lithium-ion based technology that has a nominal full charge of 390 VDC, a 16 kWh capacity, and a control system that incorporates liquid (antifreeze) cooling and various electronic devices (control modules, sensors, wiring, etc) to monitor and manage the HV battery. The HV battery, portions of the cooling system, and the control system are contained within a common enclosure. During an NCAP oblique side pole impact test conducted by NHTSA in May 2011, the pole struck and deformed the sill plate under the driver's door at a location where there is a structural member. The lateral member displaced inward, pierced the HV battery enclosure and battery, and caused a battery coolant leak. Thereafter, the Agency conducted a rollover test (the rollover test consists of four 90-degree rotate-and-hold movements about the vehicle's longitudinal axis). In that test, the HV battery and electronics were exposed to coolant that leaked as a result of the crash. The vehicle fire that occurred three weeks later and the additional testing NHTSA conducted are discussed in a report titled "2011 Chevrolet Volt Battery Fire Incident Report" a copy of which is available in the public file. The report indicates that intrusion induced coolant leakage, and subsequent rollover that saturates electronic components, were the only test conditions which resulted in a subject vehicle HV battery fire. GM announced its intention to conduct a free-of-charge customer satisfaction campaign (CSP) on the subject vehicles on January 5, 2012. The action affects 14,735 vehicles produced prior to December 21, 2011. The CSP addresses three areas related to the issue under investigation. The first involves a modification/strengthening of the structure of the vehicle in the area where battery intrusion occurred in the May 2011 te

About This Investigation Type

A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.

Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. about how PlainCars sources NHTSA data.