Article on Teslas own battery cell production near their Fremont factory. Includes estimate of battery production capacity.
"A 6 MW supply provides 6,000 kWh of energy per hour of operation. This would support 100 kWh of Cell production per hour of operation.100 kWh x 24 x 7 x 50 = 840 MWh of Cell production per year = 0.84 GWh per year on a 7/24/50 operation schedule = about 13,000 MY / M3 units."
