It is not uncommon for manufacturers of 'systems' to hedge their bets by becoming suppliers of components to competitors. Examples abound in the cell phone indu

It is not uncommon for manufacturers of 'systems' to hedge their bets by becoming suppliers of components to competitors. Examples abound in the cell phone industry: Samsung makes Apple's A series chips and possibly, other components. It is not a certainty that Tesla's battery manufacturing facilities can lower the price of batteries to achieve the < $30k per-car price point. I'd imagine a single factory that also sells to other car makers will solve the existing problem with scale. Currently, making/procuring 10k batteries a year is probably a big factor in making them so costly. It is almost universally true that manufacturing in larger numbers will bring down the price (probably not in a linear way, rather logarithmically).