It combines a 2-liter DOHC 16V Duratec (Atkinson cycle) engine and CVT with an AC synchronous motor powered by a 7.6kWh Lithium Ion battery.

ENGADGET

It has a 2-liter DOHC 16V Duratec engine and a 7.6kWh Advanced Lithium Ion battery (the regular C-MAX hybrid uses a 1.4kWh battery instead) that unfortunately takes up quite a bit of room in the trunk.

ENGADGET: Ford C-MAX Energi plug-in hybrid test drive (video)