In a factory beside a paddy field on the outskirts of a small city in central China, one of the core components of the modern global economy is being produced. 

Inside a warren of cement and steel pipes, rock — mined in Australia — is heated to 1,000C in a giant coal-fired boiler. It is then leached with acid, dried and purified into a fine white powder that carries the charge inside a battery that enables an electric car to drive. The product, lithium carbonate, sells for more than $11,500 a tonne and global demand is expected to double by 2023, according to Volkswagen. 

“This all used to be countryside,” a young staff member says in the company electric car, a black Tesla Model S, as it approaches the factory gates.