Lamborghini, which has the virtue of being able to command high prices for its ultra-exclusive performance cars, is doing what cost-conscious mainstream brands couldn't pull off at this point: The 800-plus-horsepower Sián is a mild-hybrid supercar without a battery pack. 

The Sián's 48-volt e-motor, built into its transmission, uses a supercapacitor as its power reserve. Lamborghini has not provided the exact specifications for its supercapacitor, but it has revealed that it's three times more powerful than a lithium-ion battery of the same weight. 

Battery-dependent manufacturers like Tesla are racing to find new solutions that extend range and shorten charge times, while cutting demand on conflict materials. While the industry largely remains focused on improving battery technology, some manufacturers are already looking ahead to the next energy storage solution.

To many in the industry, that is supercapacitor tech—perhaps in conjunction with a somewhat slower and more stable battery chemistry, or with part of the powertrain downsized.

Lamborghini Sián hybrid hypercar

Lamborghini Sián hybrid hypercar

In the Sián, the supercapacitor provides enough power to the e-motor to deliver an extra 34 horsepower. Lamborghini uses this to smooth out acceleration, bridging the gaps in power delivery that occur when the mechanical transmission changes gear. Lamborghini says this approach removes any jerkiness that would normally occur during a shift. It also makes the Sián quicker since there are fewer gaps in its acceleration. 

Because supercapacitors can be charged and discharged symmetrically, they make for an incredibly efficient means of providing a short but strong electric assist in a vehicle being driven around a track. The supercapacitor is discharged during acceleration and recharged during braking, meaning in that situation the e-motor virtually never lacks the power it needs to do its job.

This isn't the first time Lamborghini has utilized supercapacitor technology in its flagship performance car. The Aventador, which was Lamborghini's previous range-topping model, employed a supercapacitor in its auto-stop-start system rather than a battery-powered starter.