Coming in 2012, a hybrid version of the flagship Audi A8 sedan will team a 2.0-liter turbocharged gasoline engine with an electric motor generator and self-charging 1.3 kWh lithium-ion battery pack to realize an impressive 37 mpg.

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In addition to the petrol engine and electric motor, the LF-CC hybrid drive system further comprises a generator, a high-performance battery, a power split device which, via planetary reduction gears, combines and re-allocates power from the engine, electric motor and generator according to operational requirements, and a compact power control unit to govern the high speed interaction of the system components.

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By applying the brakes or reducing speed by letting off the accelerator, the electric motor acts as an electric generator, converting energy that would otherwise be wasted into battery energy.

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His discoveries laid the foundations for the electric motor and the electrical generator, and thus for electrification in general.

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In this case, however, the front electric motor-which is now supplied with energy by the TDI engine-operates exclusively as a generator and a power source for the electric motor at the rear.

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The 1.4-liter gasoline engine under the hood functions as a generator, creating juice for the electric motor.

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The Lexus' whirligig is familiar from the Toyota Camry and Avalon hybrids: a lean-burning Atkinson-cycle, 2.5-liter in-line four-cylinder (156 hp) coupled with two electric motors, one a 141-hp traction motor, the other a starter-generator.

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