Mazda to begin deployment of i-ELOOP ultracapacitor-based regenerative braking system for passenger vehicles in 2012

Mazda’s ‘i-ELOOP’ regenerative braking system. Click to enlarge.

Mazda Motor Corporation has developed the first production passenger vehicle regenerative braking system that uses an ultracapacitor. The system, which Mazda calls ‘i-ELOOP’, will begin to appear in Mazda’s vehicles in 2012. In real-world driving conditions with frequent acceleration and braking, i-ELOOP improves fuel economy in stop-and-go driving conditions by approximately 10%, according to the company.

Compared to batteries, ultracapacitors can be charged and discharged rapidly and feature a very long cycle life. i-ELOOP converts the vehicle’s kinetic energy into electricity as it decelerates, and uses the electricity to power the climate control, audio system and numerous other electrical components.

The i-ELOOP system features a new 12-25V variable voltage alternator; a low-resistance electric double layer capacitor (EDLC) and a DC/DC converter. i-ELOOP starts to recover kinetic energy the moment the driver lifts off the accelerator pedal and the vehicle begins to decelerate. The variable voltage alternator generates electricity at up to 25V for maximum efficiency before sending it to the Electric Double Layer Capacitor (EDLC) for storage.

The ultracapacitor, which has been specially developed for use in a vehicle, can be fully charged in seconds. The DC/DC converter steps down the electricity from 25V to 12V before it is distributed directly to the vehicle’s electrical components. The system also charges the vehicle battery as necessary.

The name ‘i-ELOOP’ is an adaptation of “Intelligent Energy Loop” and represents Mazda’s intention to efficiently cycle energy in an intelligent way. ‘i-ELOOP’ also works in conjunction with Mazda’s ‘i-stop’ idling stop technology to extend the period that the engine can be shut off.

Source: Green Car Congress