First production vehicle employing a 48 V electrical system

Bentley Bentayga W12 2016

BENTLEY’S 97th anniversary marked a signi cant year in the British marque’s history with the launch of the automaker’s

rst-ever SUV, the Bentayga. That same year, the VW Group used the Crewe-based brand to introduce 48 V mild-hybrid technology that would in uence the development of future internal-combustion engines (ICE). Bentley debuted the innovative setup in the Bentayga W12. It comprises a 48 V lithium-ion battery, connected to the conventional 12 V item via a low-voltage DC/DC converter, and an integrated belt alternator starter, which is mated with the 2,4-tonne behemoth’s 6,0-litre twin-turbocharged petrol mill. The Bentayga W12’s “electri ed” unit produces 447 kw and 900 N.m of torque available from 1 250 r/min.

Unlike traditional hybrid powertrains, the Bentley’s mild-hybrid setup’s electrical system cannot operate independently from its ICE. Instead, the 48 V cell acts solely to supplement the fossil-fuel powerplant, as the small battery pack doesn’t have suf cient voltage to drive the wheels by itself. There are, however, bene ts to this setup.

Four times as powerful as the standard 12 V item, the additional battery has ample capacity to power the vehicle’s electrical systems, such as power steering and – in the application of the Bentayga W12 – activating Bentley’s Dynamic Ride active anti-roll bars when cornering. Thanks to the mild-hybrid arrangement, the start/stop system is smoother in its workings, while it – together with the regenerative-braking system – improves fuel consumption and reduces CO2 emissions.

The 48 V mild-hybrid architecture soon found its way into other vehicles from the VW Group. Employing a similar engine as the Audi SQ7 TDI, the Bentayga Diesel – sporting a 4,0-litre twin-turbocharged V8 diesel, replete with electric supercharger and 48 V system – is Bentley’s rst diesel car. Underpinned by VAG’S MLB platform, the Bentayga Diesel’s con guration also spools the supercharger to eliminate engine lag.

German rm Continental predicts that by 2025, cars employing this cost-effective technology will account for around 14% of all new-vehicle sales.