Nissan will almost double the number of workers at its factory in Smyrna, TN, within the next year in part to ramp up production of both Nissan Leaf electric vehicles and battery packs, HybridCars reports.

Nissan will add 1,300 workers specifically for the battery packs and for the Leafs, which will start being built in the U.S. later this year. The Japanese automaker has invested $1.7 billion upgrading the plant, which will include a 1.3-million-square-foot facility dedicated to making battery packs. In all, Nissan will employ about 6,000 at the factory by early next year.

With the improvements, Nissan's plant in Smyrna, about 25 miles southeast of Nashville, will be able to produce as many as 200,000 Leafs and 150,000 battery packs a year. Last month, Nissan sold 478 Leafs in the U.S., marking a sevenfold increase from a year earlier though down from the 676 Leafs sold in January. In 2011, Nissan sold 9,674 Leafs, slightly less than the company's target of 10,000 units for its first full year of U.S. sales.