The UAW fought for protection if factories shut down. But workers in other carbon-intensive industries could find themselves displaced.
Even though prices have come down and the federal government is helping with rebates, the average price is still above $50,000.
It's a small market so far, but using the excess supply of used batteries could help meet the high demand for stored clean energy.
The government is lending $9.2 billion to Ford and a Korean partner to build electric vehicle battery factories in Kentucky and Tennessee.
GM is launching an electric version of its Chevy Equinox SUV with a price tag that starts around $30,000. It's hoping to reach a broader market.