Tesla Model S receives titanium under-armor to prevent fires

Tesla has developed new underbody protection for the Model S against road debris, in reaction to fires last year that resulted from the battery pack being punctured. The update will be offered to current owners and made standard on new cars. The protection has been installed at the factory on new models since March 6, 2014.

The three components are designed to protect the lithium-ion battery pack that runs across the bottom of the Model S. The first is an aluminum bar to deflect debris and prevent it from reaching the battery pack. The second is a new titanium shield behind the aluminum bar that increases protection for the front of the battery. The third is a new angled aluminum plate designed to lift the body of the Model S up and over a solid piece of road debris, if all else fails.

This new protection is in addition to the Model S's existing hardened aluminum battery housing that was punctured in the fires last year. Tesla also issued a software update last fall to raise the ride height of the Model S at highway speeds to carry it over such obstacles. No one was injured in the incidents, because the fires started slowly, remained in the front underbody of the car, and the cars warned their drivers to pull off the road and exit the car before the fires spread.

In a letter on Tesla's website, the CEO and "vehicle architect" Elon Musk says the company will "retrofit the shields, free of charge, to existing cars upon request or as part of a normally scheduled service" at a Tesla service center.

Tesla has posted three videos showing the Tesla running over large, heavy objects, including a three-ball steel trailer hitch as happened in one of the 2013 accidents. The letter goes on to say that the added hardware will reduce the car's range by less than 0.1 percent, or less than three miles.

The action comes in response to an investigation into the fires begun last year by the National Highway Traffic Safety Administration, which Tesla says has now been closed.

–Eric Evarts

Update: We had the upgrade made to our Tesla, and it proved to be an easy, convenient fix.