Tesla Motors has doubled the number of people building its US$5 Billion battery in Sparks, Nevada way ahead of schedule to meet the demand expected from its upcoming Model 3 electric sedan and its more accessible price tag.

"We have to be ready with cell and pack production well ahead of vehicle production," said Tesla's chief technical officer JB Straubel to the Wall Street Journal.  "We're accelerating our construction plans and accelerating our planned ramp up of cell production," he added.

There are now 1,000 workers on two shifts operating seven days a week at the site near Reno.  The goal is to get the place up and running and churning out  lithium-ion cells by the end of this  year, and keep up with the introduction of the Model 3 next year.  The new car is expected to retail for around US$35,000 in America and AU$60,000 in Oz, making it about half the price of the Model S.

Tesla founder Elon Musk has big plans to expand the automaker'slines to include buses and trucks.  Tesla will also incorporate a new energy-storage business that augments the battery business with solar panels from Solar City, Musk's other business that he wants to merge into one with Tesla.  Solar City cells will line the roof of the factory in Sparks, and even more will form a solar array nearby to provide even more power.