Cadillac's CT6 Plug-In Hybrid was unveiled a year ago at the Shanghai Auto Show, but full details on the sedan's advanced powertrain are only now being released. As previously reported, the CT6 borrows some components from the second-generation Chevy Volt, adapting them to a rear-wheel-drive platform.

The powertrain consists of a 2.0-liter turbocharged 4-cylinder engine, two electric motors, and an 18.4-kilowatt-hour lithium-ion battery pack—which is the same capacity as the Volt's pack. Total system output is 449 horsepower. Cadillac claims 0-62 mph acceleration in 5.6 seconds and an electric-only range of 37 miles, although official EPA ratings for the latter aren't in yet.

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Using a Volt-sized battery pack gives the CT6 much more storage capacity than other luxury plug-in hybrids. Unlike the T-shaped arrangement of the Volt, which places the pack in the tunnel under the front seats and between the rear seats, the CT6 pack is integrated in the vehicle floor. The battery-pack tray actually serves as the main floor structure, increasing stiffness, said Tim Grewe, General Motors Company [NYSE:GM] general director of electrification, during a presentation attended by Green Car Congress.

2017 Cadillac CT6 Plug-In Hybrid

2017 Cadillac CT6 Plug-In Hybrid

Components taken straight from the Volt—including common electronics and the battery-state estimator—are housed in a separate tray. The CT6 also uses a similar two-motor drive system to the Volt, with an additional planetary gearset (for a total of three) and two more clutches (for five). Grewe described it as a "Volt on steroids."

The two motors are different designs. One is an induction motor, which GM chose because it does not use rare-earth metals, and the other is a permanent-magnet motor based on the one used in the Chevy Spark EV. The latter will be manufactured at the same White Marsh, Maryland, plant that builds Spark EV motors. The battery pack will come from GM's Brownstown plant in Michigan, with cells from the LG Chem Holland plant across the state.

However, the CT6 Plug-In Hybrid will be built exclusively in China. That will make it the first Cadillac imported for sale in the United States, and one of a small number of U.S.-market cars built in China. GM will do the same with the 2016 Buick Envision crossover, which goes on sale in the U.S. later this year.

The car is due on sale late this year or early next, as a 2017 model. Regular versions of the CT6 are already on sale.


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