A factory making lithium-ion batteries for hybrid- drive cars opened in Germany Wednesday, with owner Continental saying it was the first in the world to mass-produce the storage cells.

Smaller lithium-ion (Li-ion) rechargeable batteries for laptop computers and other uses are common round the globe, but most fuel- saving hybrid cars use an older technology, nickel metal hydride (NiMH) batteries.

German components group Continental's factory in Nuremberg will make batteries weighing 25 kilograms and allow electric motors in cars to supplement the output of combustion engines by up to 19 kilowatts of power.

The technology is to be installed in Mercedes S400 Blue Hybrid cars from the middle of next year, Continental said.

The factory can make up to 15,000 of the batteries per year.