The i3’s Drive Module is provided by BMW’s Dingolfing plant and completed at Leipzig. It is screwed and glued to the Life Module. The underfloor lithium-ion battery has eight modules and 96 cells. Although the cells are supplied, the battery modules are a proprietary development of BMW and manufactured at Dingolfing. The individual battery blocks each have their own safety system.
The car’s air conditioning refrigerant cools the i3’s battery pack, obviating the need for fans or additional pumps. Heat for preconditioning in low temperatures comes from the charging electricity supply. The cabin is heated via a heat pump in urban traffic, a 30% saving against regular electric heating. Battery performance typically shows a 5% degradation at -15°C (+5°F), and testing has been completed down to -35°C (-31°F).
LEDs are used for interior and exterior lighting. The i8 will use a laser lighting system; full details will be released later. The i3 has a bipolar electrical system with the earth wired as a separate and fully insulated line.