Mazda has released the details of ‘i-ELOOP’ – a regenerative braking system it claims will reduce the fuel consumption of its future vehicles by up to 10 per cent.
The Japanese manufacturer says i-ELOOP (which stands for ‘Intelligent Energy Loop’) is the world’s first capacitor-based regenerative braking system for a passenger vehicle.
Mazda has confirmed the fuel-saving technology will debut in its passenger vehicle range in 2012. We will get our first look at i-ELOOP at next week’s Tokyo Motor Show when Mazda unveils the Takeri – the concept that previews the next-generation Mazda6, which is expected to go on sale in Australia in 2013.

Mazda says i-ELOOP improves fuel efficiency in stop-start city traffic by as much as 10 per cent. It works in tandem with Mazda’s ‘i-stop’ start/stop system, extending the length of time the engine can be in shutdown mode.

Conventional regenerative braking systems in hybrid vehicles use an electric motor/generator to recover kinetic energy produced at the brakes during deceleration. The recovered energy is stored in a battery and used to help power the vehicle’s electric motor to increase efficiency.

Unlike these systems, Mazda’s i-ELOOP does not need a dedicated electric motor or battery. i-ELOOP incorporates a 12-25 volt variable voltage alternator, a low-resistance electric double layer capacitor and a DC/DC converter. The system starts to recover kinetic energy as soon as the driver lifts off the accelerator pedal and the vehicle begins to decelerate.

The alternator generates electricity and sends it to the capacitor for storage. The capacitor can be fully charged in seconds. The converter reduces the electricity from 25 volts to 12 volts before distributing it to the vehicle’s electrical components (climate control, audio system, etc.) and charging the vehicle battery where necessary.

i-ELOOP is the latest development in Mazda’s SkyActiv series, which aims to reduce fuel consumption and emissions across the entire range by implementing efficient powertrain components and lightweight materials.

Mazda calls i-ELOOP ‘Step Two’ in its Building Blocks strategy, following the development of i-stop (Step One). Step Three, the next phase of development, is electric drive technology.