Tesla Model S battery fire inquiry closed by NHTSA

The National Highway Traffic Safety Administration said it closed a three-month-long investigation of fires in the Tesla Model S this week, as Tesla announced a design change to better shield the electric car's batteries.

Tesla Motors Inc. said today it has started building the Model S with a titanium underbody shield to prevent battery fires like the two that occurred in the United States last year when Model S drivers struck road debris. Tesla CEO Elon Musk announced the design change in an article on the Web site Medium.com, saying that all Model S vehicles built after March 5 have the shield. Owners of cars built before that date may have the shield added upon request.

Hitting road debris is inevitable, NHTSA documents say. By raising the car's ride height through a software upgrade last fall, and adding the titanium shield, Tesla reduced the likelihood and danger of such a strike, the agency concluded.

The agency's defect investigation office “believes impacts with road debris are normal and foreseeable,” the documents say. “In this case, Tesla's revision of vehicle ride height and addition of increased underbody protection should reduce both the frequency of underbody strikes and the resultant fire risk. A defect trend has not been identified. Accordingly, the investigation is closed.”

Musk had vigorously defended the safety of the Model S last year, even after regulators opened their formal investigation in November. In today's article, he said the change would have value, by “minimizing owner inconvenience in the event of an impact and addressing any lingering public misperception about electric vehicle safety.”

“With a track record of zero deaths or serious, permanent injuries since our vehicles went into production six years ago, there is no safer car on the road than a Tesla,” Musk wrote. “The addition of the underbody shields simply takes it a step further.”

The article, NHTSA closes Tesla fire inquiry as Model S gets new battery shield originally appeared at Automotive News.

By Gabe Nelson- Automotive News