The move represents a huge vote of confidence in the near-term centrality of rechargeable-battery technology to the solar industry.

Lithium, an alkali metal, is used as an anode in rechargeable lithium-ion batteries used in electric cars, solar batteries, laptops and a host of other technologies expected to grow enormously in the coming decades.

The Erzebirge range, which separates the German state of Saxony from the Czech province of Bohemia, is estimated to contain one of the world’s 10 largest stores of lithium.

Sven