Audi reveals S6 and S7 TDI models with mild-hybrid diesel powertrains

The sportier models use a V6 diesel and a 48-volt electrical system that develops 344bhp.

Audi has unveiled the new versions of the S6 and S7, which now use diesel-electric powertrains.

The 3.0-litre V6 engine is paired to a 48-volt electrical system, which is teamed with an eight-speed automatic transmission and quattro all-wheel drive – although the use of a diesel unit instead of a petrol is a surprising one.

With that setup, the S6 and S7 models have 344bhp and 700Nm of torque at their disposal, which in the S6 saloon allows a 0-60mph time of 4.8 seconds. The S6 Avant and S7 Sportback reach the same point in 4.9 seconds.

All three vehicles have an electronically-limited top speed of 155mph.

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The 48-volt mild hybrid system is made up of a belt alternator starter (BAS) and a lithium-ion battery – with the BAS employed as a starter motor to get the car underway and can recover energy usually lost through braking and coasting.

Design-wise, the S models come with dark chrome and aluminium detailing on the grille, side inlets, exterior mirrors and rear diffuser – while each model comes with unique features. Large alloy wheels also complement each car to further the sport aesthetic.

Inside, the sports seats are fitted with S embroidery and trimmed in either leather and alcantara or the top-spec Valcona leather. The Virtual Cockpit 12.3-inch instrument display and four-zone climate control also come as standard.

UK pricing and specification are yet to be released, with models set to go on sale in the summer.