A ‘plug-in’ version of the third-generation Toyota Prius powered by lithium ion batteries will be ready for market early in 2010.

In an exclusive interview for Autocar, Toyota’s Executive Vice President responsible for research and development, Masatami Takimoto, confirmed that the company’s long-standing scepticism towards lithium ion battery technology has now been put to rest.

“We have made much development progress with lithium ion batteries over the last six months,” said Takimoto. “We are now convinced that they can be used in our future plug-in hybrid and all-electric vehicles, although our cheaper hybrid models will continue to use nickel metal hydride batteries.”

The first of Toyota’s lithium ion-powered cars will be a ‘plug-in’ version of the Prius, which will be available in Japan later this year, and will come to the UK in very limited numbers at first in early 2010.

The car’s zero-emissions electric-only range – the distance it will travel on battery power alone after a full mains charge – is not yet set in stone, but it’s expected to be no more than 20 miles. That being the case, however, it will need a much smaller lithium ion battery pack than the GM Volt, and so will be cheaper; expect a sub-£30k price tag.

Extended electric-only running won’t be the only thing going for the ‘plug-in’ Prius, however. Toyota has been trialing the lithium ion battery technology in collaboration with EDF Energy, in development cars running around Paris. It has found them to return between 60 and 80 per cent better fuel economy than the nickel metal hydride version once the combustion engine comes into play, depending on usage.

Takimoto also confirmed Toyota’s plans for a lithium-ion battery only ‘EV’ city car – “not an iQ, but something similar in size,” – which will arrive in 2012.

Matt Saunders

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