Lamborghini PHEV features V12 powertrain

LAMBORGHINI has announced its new electrified LB744 plug-in hybrid model, a replacement for the Aventador with a naturally aspirated V12 petrol engine and three high-output axial flux electric motors.

The unnamed vehicle is due for launch later this year coinciding with the Italian brand’s 60^th anniversary.

With six decades of naturally aspirated V12, and more recently V10 power, at its disposal, the Volkswagen- owned supercar company had marked ‘the end’ of the ICE V12 era through a number of special editions… while at the same time leaking information about its latest model.

Lamborghini portrays the new LB744 as ‘the new benchmark for hybrid super sports cars’ as well it might, due to the 745kW+ (1000hp+) combined power output. However, the new Lambo PHEV has some serious competition from various quarters including Ferrari, McLaren, Porsche, Koenigsegg and many others.

The LB744 boasts many advanced engineering solutions including the powertrain which features a newly developed eight-speed dual-clutch, rear-mounted, transverse gearbox with an electric motor (and starter) attached to facilitate four-wheel drive in full electric mode.

Thanks to a new mid-engine chassis, the LB744 has a lightweight, high-power lithium-ion battery in the central section where most previous Lamborghinis had a transmission tunnel. This innovative solution is designed to maximise performance while evenly distributing weight, lowering the centre of gravity and thereby improving the car’s dynamics.

The LB744’s 6.5-litre V12 petrol unit is also a completely new design, with electric motors to boost power delivery at low revs that can also be used to give the supercar purely electric drive with benefits in CO2 reduction.

Lamborghini has been dabbling in hybrid electric assistance to a V12 combustion engine since 2019’s Sian concept car which used a 25kW electric motor ‘mild hybrid’ unit, storing electrical energy in a supercapacitor.

Before that, and going back to 1963, the main focus at the company was on ICE V12s with a V10 becoming available when Volkswagen took over in 1998.

The LB744, dubbed a High Performance Electrified Vehicle (HPEV) by Lamborghini, utilises the new L545 engine – which is the lightest and most powerful V12 ever made by the company.

For an internal combustion engine of this size and configuration, it tips the scales at a relatively light 218kg, some 17kg less than the Aventador unit, and goes some way towards offsetting the additional weight added by three electric motors and a large battery pack.

The LB744’s engine is rotated through 180 degrees compared to the Aventador layout. The ‘superquadro’ V12 puts out 606kW at 9250rpm thanks in part to a redesigned induction and fuel system that supports a maximum rev range of up to 9500 rpm.

Specific power output is 94kW per litre, which is the highest output in the history of Lamborghini’s V12 engines. Maximum torque is listed at 725Nm at 6750 rpm.

Air intake ducts to the cylinders have been re-engineered to increase the supply of air and guarantee optimal airflow in the combustion chamber. The combustion chamber shape has been optimised to efficiently propagate flame aided by an ionisation (electric charge) process with two control units, something already seen in the Aventador and now transferred to the new model.

The compression ratio is a high 12.6:1 while fluid dynamics was used in the exhaust’s design to reduce unwanted back-pressure at high revs and increase specific power output. This has had a secondary benefit to the sound emitted from the new model’s exhaust which Lamborghini says is “emotional and unmistakable”.

All-wheel drive is a strong Lamborghini tradition and the LB744 follows through with the combustion engine and transmission-mounted electric boost motor driving the rear axle and two electric motors, one a side, driving the front.

The rear mounted electric motor is only engaged when maximum performance is required along with the selection of the necessary driving mode while the two 110kW front electric motors are oil-cooled high efficiency axial flux units that offer an ‘exceptional power to weight ratio’.

A torque vectoring function naturally arises from having individual electric motors on each front wheel. A secondary benefit is recuperative energy recovered under braking.

In electric mode, the LB744 is front-wheel drive only in a bid to save energy.

The LB744’s lithium-ion high specific power (4500W/kg) battery pack is protected by a lower structural layer and is connected to the front electric motors, the rear electric motor and an integrated recharging unit.

It measures 1550mm in length, 301mm in height and is 240mm wide with ‘pouch’ cells giving an overall capacity of 3.8kWh. When the charge drops down to zero it can be recharged using both ordinary domestic AC charging up to 7kW in power and completely recharges in 30 minutes.

The battery can also be recharged under regenerative braking from the front wheels or directly from the V12 engine in just six minutes.

The new platform facilitates the adoption of innovative technology particularly the gearbox which, Lambo says is the ‘the nerve centre of the hybrid plug-in unit’. It is a compact design that can withstand a potent electric power unit and was developed and designed by Lamborghini entirely in-house for use in this and future Lamborghini electrified models.

A wet double clutch design was favoured for its size and ability to manage the masses of torque now on offer. Lamborghini says the new DCT ‘box is lighter and faster in terms of shifting speed compared to the seven-speed double clutch unit used in the Huracán range.