Range anxiety isn't the only worry of some prospective Tesla Model S buyers. There's also a slim possibility that the electric car's battery could die permanently if left uncharged. When that happened to one Tesla Roadster, the company initially blamed the buyer. "If you ran your conventional engine without oil, whose fault would it be? It would be the owner's," said Tesla CTO J. B. Straubel. That left the unlucky owner facing a $40,000 battery replacement fee. Today, however, Tesla CEO Elon Musk has announced that his company will bear the cost of almost any battery failure with what he calls the "world's best warranty service."

"Any car that needs a manual to work is broken."

"Except in the cases of a collision, opening of the battery pack by non-Tesla personnel or intentional abuse (lighting the pack on fire with a blowtorch is not covered!), all damage is covered by warranty, including improper maintenance or unintentionally leaving the pack at a low state of charge for years on end," the company's announcement reads.

Should the battery die, Tesla will replace it at no cost with a battery of equal or better energy capacity. Tesla's battery warranty currently lasts eight years. "In developing the Model S, we took great care to ensure that the battery would protect itself, always retaining a few percent of energy. If something goes wrong, it is therefore our fault, not yours," reads the release.

On a conference call to discuss the announcement, Musk made it even clearer: "Any car that needs a manual to work is broken," he said.

"Even if you never bring in the car, your warranty is still valid."

Tesla's also making the warranty program more foolproof in general, allowing owners to maintain their warranty even if they never bring the car to a dealership for service or inspection, and building a fleet of Model S loaner vehicles, which it will hand-deliver by valet to any owner who needs a temporary replacement, or even trade for the existing Model S should they like the loaner better. "What's the best service and warranty that we could possibly envision and still afford to do? That's what we came up with here," he said.

Musk told reporters that his intent for the new warranty is to reduce any lingering doubts prospective buyers might have about purchasing an electric car. "I want to give people peace of mind ... I want them to have the happiest possible transport experience."