The Aventador-based Sian is the first ever hybrid car built by Sant’Agata, although strictly speaking it is only a mild hybrid. Interestingly, Lamborghini uses hybrid technology not for efficiency but performance. Therefore, it opts for a supercapacitor instead of battery to store the electric energy. The supercapacitor is mounted ahead of the engine. It can be recharged from braking. Its capacity is unspecified, but should be much smaller than conventional Li-ion batteries. On the plus side, its power density is much higher, so it can be light and small yet generate high power at a short burst. The electric motor is low-voltage, running at only 48V like most mild-hybrid cars from the Volkswagen group. It is incorporated into the gearbox, providing only 34 horsepower to assist the 6.5-liter V12 engine, which is enhanced to 785hp (15hp up from SVJ). Combined maximum output is therefore 819hp.
The electric system with the supercapacitor and e-motor weighs only 34 kg, a lot less than the 270kg worth of 3 motors and lithium battery on Ferrari’s latest SF90 Stradale. This means the Sian won’t be much heavier than the 1620kg kerb weight of SVJ. The power of e-motor fills the torque gap during gearshifts. Considering how violent the shifts of Lamborghini’s ISG gearbox could be, this could be the best benefit.
Concerning absolute performance, the addition of 34hp seems to have little effect on figures. Lamborghini quotes the same 0-62 mph time of 2.8 seconds and the same top speed of 217mph+. Its superiority is reflected more on in-gear acceleration.
Apart from hybrid power, the Sian gets a completely new packaging, which is said to be inspired by Countach (I’m not sure…). Only 63 cars will be built, and all have been spoken for. Pricing is yet to be revealed, but it is undoubtedly a million-dollar hypercar.