The High-voltage battery for the BMW 740e/Le is stored beneath the rear seat, keeping it secure and saving space. As a result, the luggage compartment is slightly smaller than in conventional models (420 litres).
The battery can be charged with the cable supplied, from conventional household 230 volt power sockets or at a public charging station. During travel the electric motor sometimes acts as a generator, converting kinetic energy into electricity (recuperation), which it stores in the battery.
Thanks to lithium-ion technology, the liquid-cooled High-voltage battery has a high energy density and comparably compact dimensions. With a capacity of 9.2 kWh, it can deliver up to 70 kW (95 hp) to the electric motor at a moment's notice. When fully charged, it makes a purely electric range of up to 40 km possible in a BMW 740e, as well as an electric maximum speed of up to 120 km/h.