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What is a mild-hybrid?

The hybrid performance car is no longer an oxymoron. Here’s how manufacturers are using this new tech to make them better, not just greener

Mild-hybrid is certainly a buzzword in 2020 automotive development, being quickly integrated into all levels of combustion powertrains to lower emissions relatively cheaply and without need of any major packaging redesign. Performance versions of normal saloons and estates, such as the Mercedes-AMG E53 and Audi S4 TDI, are two examples of manufacturers applying this technology to both petrol and diesel powertrains.

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The hardware usually consists of a small electric motor, mounted directly on the combustion engine, that assists drive as well as takes the place of a traditional starter motor. This starter motor and generator is generally powered by a small battery pack via a supplementary 48V electrical system that works alongside the normal 12V circuit. The battery itself is recharged by regenerative braking, negating the need for any roadside charging.

Some cars, such as the E53 and S4, also feature small electrically powered compressors that work in conjunction with the gas-powered turbos, improving response by spinning up the turbines before the exhaust gases have the chance to reach them. These systems also power energy-heavy chassis hardware such as active anti-roll bars that a normal 12V system wouldn’t otherwise be able to support.

Mild-hybrid performance cars:

Pro: Lightweight, compatible with a big variety of IC powertrains

Con: Has only a subtle effect on reducing consumption and increasing performance

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