Electric car maker Tesla Motors has signed a deal with Japan's Panasonic Corp. to expand its supply of battery cells.
Under the pact announced early Wednesday, Panasonic will supply nearly 2 billion cells over the next four years. The automotive grade lithium-ion battery cells will power the Model S sedan as well as the Model X SUV, which is scheduled to go into production by the end of 2014, Tesla said.
The agreement amends a 2011 contract between Panasonic and Tesla that promised enough cells for 80,000 vehicles -- or approximately 560,000 cells -- through 2015.
Tesla expects to deliver 21,000 Model S sedans worldwide this year. The company has estimated sales could nearly double to 40,000 next year as the Model S goes on sale in Europe and Asia.