Tesla says gas-powered cars five times more likely to burn than a Model S

Tesla co-founder Elon Musk revealed more details Friday about the first fire in a Tesla Model S sedan and in his usual manner, aggressively defended the safety of the cars following a wild stock market reaction to the crash.

No one was injured in the fire Wednesday outside Seattle, and the Tesla's owner -- a Boeing engineer who happens to also be a Tesla investor -- told the company he was impressed with how the fire was contained by the car. Yet the first blaze has sparked days of pearl-clutching around Wall Street and in some forums over the safety of lithium-ion batteries — at one point paring more than $2 billion from the company's market value.

In a Tesla blog post, Musk said that a piece of a semi trailer had punctured the front battery compartment of the torched Model S, and that the shielded compartment had worked properly to shunt the flames away from the vehicle. He also noted that the battery pack contains far less energy than a gasoline tank in a similar-sized sedan, estimating that a Model S had only about 1 percent of the flammable energy of a gasoline-powered car.

"For consumers concerned about fire risk, there should be absolutely zero doubt that it is safer to power a car with a battery than a large tank of highly flammable liquid," Musk wrote. "You are 5 times more likely to experience a fire in a conventional gasoline car than a Tesla!"

Fire officials had said they had some minor problems extinguishing the blaze after they poured water on the battery pack. Musk said Tesla's review found the firefighters had poked extra holes in the battery pack, which allowed the flames to spread to the front trunk. The fire was stopped with a combination of water and dry chemicals.