Mazda Gets Loopy With New Capacitor-Based KERS

Mazda has laid claim to developing the first capacitor-based regenerative braking system for a passenger vehicle, dubbed i-ELOOP - intelligent Energy Loop.
The technology has shown up in racing cars before (see Toyota's Supra HV-R), but Mazda's project marks its first appearance in a regular passenger car.
The system works like a regular regenerative braking system, but the energy is stored in a capacitor rather than the more common battery arrangement.
The i-ELOOP system is made up of a 12-24V variable voltage alternator, a low-resistance electric double-layer capacitor and a DC/DC converter.
Like most systems, i-ELOOP recovers kinetic energy as the vehicle is decelerating, which the alternator uses to generate electricity that is then sent to the capacitor.
The stored energy is used to power the vehicle's climate control, audio system and other electrical features. The system will also charge the vehicle's battery when necessary.

Mazda says the advantage to using a capacitor its ability to be charged and discharged rapidly, and, compared to batteries, a stronger resistance to deterioration.
The big win for the driver however is that because the system does not use a dedicated motor or battery to operate and is therefore using less power, the vehicle's fuel economy is improved by "approximately" 10 percent.
The system is designed to work alongside Mazda's i-stop idle-stop technology, allowing the engine to remain switched off for longer periods.
Mazda has yet to announce production plans for the technology, but expect i-ELOOP to appear in the next-generation Mazda6 or Mazda3.

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