Land Rover will be unveiling seven new Defender electric models at the 2013 Geneva Motor Show. The Defender research vehicle boasts of being able to go anywhere without harmful emissions. Land Rover replaced the standard diesel engine and gearbox in the Defenders 110 with a 70kW (94bhp) 330Nm electric motor powered by a 300-volt, lithium-ion battery having a capacity of 27kWh.
This allows the Defender EV to have a range of over 50 miles. The battery can last for up to eight hours without recharging if the vehicle is subjected to low speed off-road use. Once empty, the battery can be recharged by a 7kW fast charger in just four hours or by a portable 3kW charger in 10 hours.
The EVs retain Defender’s legendary four-wheel drive system and differential lock. There is no need for a driver to gear shift since the electric motor already provides maximum torque from the start. Transmission for the Defender EVs includes a single speed, 2.7:1 reduction gearbox combined with the existing Defender four-wheel drive system.
Land Rover also installed a modified version of its Terrain ResponseSystem in the EVs. The EVs were developed by Land Rover’s Advanced Engineering Team after holding successful trials of Leopard 1, a Defender-based electric vehicle. Land Rover tested the EVs’ capability in extreme and environmentally sensitive conditions, which saw them exhibit capabilities not shared by conventional EVs.
The Defender EVs underwent trials like pulling a 12-ton ‘road train’ up a 13-percent gradient as well as wading to a depth of 800mm. The 410-kg battery is mounted in the front of the Defender in lieu of the diesel engine.
The Defender EV has a kerb weight that is 100kg more than a basic Defender 110, ranging from 2055kg to 2162kg and depending whether the body style is a pick-up, hard top or station wagon. All the major parts of the electric powertrain -- including the battery, inverter and motor -- are air-cooled to save weight and complexity and to add robustness.
Land Rover optimized regenerative braking to an extent that using Hill Descent Control allows the motor to generate 30kW of electricity. Since the battery can be charged very quickly at a rate of up to twice its capacity of 54kW without cutting battery life, it is possible to recover and store almost all of the regenerated energy.