Ford said new 48 volt 'mild hybrid' Fiesta and Focus EcoBoost Hybrid models would be introduced in 2020, "bringing the benefits of electrification to greater numbers of consumers".
The new models will have a sophisticated mild hybrid architecture tailored to enhance fuel efficiency with more powerful and responsive performance.
A belt driven integrated starter/generator (BISG) replaces the standard alternator, enabling recovery and storage of energy usually lost during braking and coasting to charge a 48 volt, lithium ion, air cooled battery pack.
The BISG also acts as a motor, integrating with the low friction, three cylinder one-litre EcoBoost combustion engine and using the stored energy to provide torque assistance during normal driving and acceleration, as well as running the electrical ancillaries.
Ford claims the electric torque assistance helps deliver punchier, more responsive performance, particularly at lower engine speeds, for more flexibility. BISG also enabled engineers to boost the engine power with a larger turbocharger, by mitigating turbo-lag.
Ford Europe earlier this year launched a Mondeo Hybrid wagon with full-hybrid architecture.

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By GlobalDataMild hybrid powertrains will also be offered in the Transit 2-tonne and Custom vans, and the Tourneo Custom eight/nine-seater people-mover, on sale later this year.
Ford recently announced all its nameplates launched from the latest Focus onwards would include one or more electrified options. This includes new nameplates and new versions of existing vehicles. Either a mild hybrid, full hybrid, plug in hybrid or full battery electric option would be offered.