The construction of the largest battery plant ever is now well into construction now in Sparks, Nevada, and will ultimately be able to produce up to:

105 GWh of lithium-ion batteriers

150 GWh battery packs

support Model 3 production in the second half of 2017

As you can see from December update video, a few of the middle sections have long been completed fully (good for almost 2 million square feet), and now expansion continues both to the north and south of the existing structures.

The southern expansion, seems near finished and will more than double the existing size of the plant, while the northern expansion that will house"additional module and pack production" and "manufacturing to support Model 3" looks to now be framed out completely.