Tesla will have self-driving cars on the roads this summer

“It’s basically impossible to run out, unless you do so intentionally,” Mr. Musk said.

The move is intended to help reduce so-called range anxiety, the fear drivers have that their battery will run out, prompting them to constantly calculate distances and worry about being stranded.

The Model S sedan already has a range that starts at just over 200 miles for the base model. Other automakers have plans to match those numbers in the coming years. Nissan, whose Leaf currently has a range under 100 miles, has announced intentions for a 250-mile-range electric car, and Volkswagen has said that it will build a car that can go 300 miles on a charge by 2020.