Lexus will unveil a more luxury-oriented version of the hybrid Prius next year at the Detroit Auto Show (same place where the next generation Prius will be unveiled). The car is internally named SAI (will get new name at launch) and will arrive in U.S. showrooms by summer 2009.

It will be a more luxurious model, more comfort orientated with unique and sleeker styling. Company inspired said there will be some similarities to Toyota’s Concept X shown at the Geneva motor show last March.

The SAI will get a more powerful version of the Prius’ hybrid powertrain, which will be mated to either a 2.0 or 2.5-liter four-cylinder gas engine. At launch it will probably have a nickel-hydride battery, but be upgraded to lithium-ion technology by the end of 2010.

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