Southern California Edison has selected Tesla Motors Inc. to build a 20-megawatt battery storage facility in Mira Loma for an undisclosed amount.

The lithium ion battery storage project will be the largest in the world, according to a Tesla blog post. The system at full charge will hold enough electricity to power more than 2,500 households for a day or charge 1,000 Tesla cars.

The cost of the energy storage facility was not disclosed. A 2-megawatt Tesla battery system costs about $2.9 million, according to Tesla’s website, although the company reportedly offers lower prices per watt for larger systems.

The facility will draw electricity from the grid at off-peak hours to charge its batteries. And then, during peak hours the system will deliver that electricity back to the grid to help stabilize the flow of power through Southern California Edition’s electrical grid.

The power storage system will be manufactured, installed, and brought online within three months, according to Tesla. The company will produce such a large-scale system quickly using the manufacturing capacity of its Sparks, Nev. battery factory, the Gigafactory.

Technology reporter Garrett Reim can be reached at [email protected]. Follow @garrettreim on Twitter for the latest in L.A. tech news.