Startups are zeroing in on cleaner ways to mine the lithium needed for electric vehicles

Teague Egan's tour of Bolivia's famed salt flat in 2018 changed the trajectory of his career. 

The flat is called Salar de Uyuni. The seemingly endless expanse of chalky white crust is home to the world's largest reserves of lithium, a key ingredient in batteries. The flat is largely untapped. 

Egan saw an opportunity.