The i3 is built around a new chassis concept called LifeDrive, which divides the vehicle into sections for Life, the passenger compartment, and Drive, the powertrain and battery. For the i3, the bottom half of the car is the Drive section, and is made mostly of lightweight aluminum; the Life passenger compartment sits on top and is built from carbon-fiber reinforced plastic (CFRP). Employing these lightweight materials keeps the i3's weight down to just 2750 pounds. The Nissan Leaf, for comparison, tips the scales at 3366 pounds.