UPDATE 1-GM offers 8-year warranty on Opel Ampera battery

* Warranty extended for 160,000 kilometres

* Durability a key concern as technology first hits roads

(Adds details, background)

GENEVA, March 1 (Reuters) - General Motors (GM.N) sought to address fears in Europe about the durability of a new generation of largely untested lithium-ion batteries equipped in its upcoming Opel Ampera by offering customers an eight-year warranty.

Electric cars like the Ampera and Chevrolet Volt are considered by many in the industry to be trailblazers into a new age of carbon-free mobility, yet the technology is so new that there are hardly any on the road.

With purchasing prices estimated to be as much as twice that of a comparable car with a conventional combustion engine, faulty battery issues that leave commuters stranded on the road remain a key concern for the industry.

GM said in July it will offer an eight-year, 100,000 mile battery warranty on the Volt, which has an expected 40-mile (64 km) range when running on electricity stored in its lithium-ion battery. [ID:nN14167451]

(Reporting by Bernie Woodall)