Electric cars are hot commodities, but there may be a problem with the new Chevrolet Volt. Fires linked to the plug-in car's battery have been reported, and a federal investigation is now underway.
A Chevy Volt battery pack caught fire one week after federal inspectors deliberately damaged it in a test, The New York Times reports.
The fire follows a similar incident in June when another Chevy Volt battery burst into flames, three weeks after another crash test by the National Highway Transportation Safety Association.
A third NHTSA crash test found the Volt's battery got markedly hotter one day after it was damaged. Yet another test found the battery, post-crash, emitted smoke and sparks.
NHTSA opened a formal investigation into the Chevy Volt fires on Friday. Other plug-in makes and models are not affected.
Despite the fire incidents, General Motors is defending the Chevy Volt as safe. There doesn't seem to be an "immediate fire risk" -- instead, it's "post-crash activity," a GM executive told the Times.
Still, GM is offering a free "loaner car" to more than 5,300 Chevy Volt owners nationwide if they are worried about the potential for Chevy Volt fires. It's not clear how long GM's loaner program will last.
The Chevy Volt runs on Lithium-ion battery cells. Coolant is pumped between the cells to prevent overheating, the Associated Press reports.
GM officially recommends "de-powering" Volt batteries after a crash, to reduce the chance of fire while the Volt is in storage.
GM says it is considering -- but has not issued -- a recall due to the reported Chevy Volt fires. But GM says it will not ship any Volts overseas until dealers are properly notified to "de-power" batteries after a crash.