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Comment by Peroni | Hacker News Reader

I don't see how regenerative braking makes a difference? Correct me if I'm wrong but if the pad comes in contact with the brake disc every time you press the brakes, regardless of whether it generates energy or not, I don't see why the compound of the brake pad would wear down any differently to standard brakes.

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What you are missing is that the Leaf is drive-by-wire -- pressing the pedal does NOT always activate the physical brakes. For light-to-medium braking, the electric motors can be operated in reverse to decelerate the vehicle.

More generally, the wear on the brake pads is roughly related to the amount of energy they soak up. Energy that gets pulled back into the battery by regenerative braking does not go towards wearing the brakes.

Regenerative breaking doesn't use pads. It basically uses engine to slow down the wheels.

Sorry but that's just categorically wrong. The leaf, just like every new car on the planet uses disks & brakes. A quick google search of Nissan Leaf brake pads will bring up tons of results for aftermarket replacement pads.

What parent said is correct, categorically or not: regenerative braking does not use conventional pad-and-disk. It uses the electric motor to slow the car by turning the motor into a generator. The fact that a Nissan Leaf has pads and disks does not change this.

This really isn't that complicated. Electric cars use a combination of regenerative braking (using the generator to convert kinetic energy; forward velocity, into electric energy) and using the disc brakes when regenerative braking doesn't slow you down fast enough. This results in much less wear on the brake pads and callipers.

Take a look at this: http://en.wikipedia.org/wiki/Regenerative_brake

Yes, the leaf has standard brakes... but it also uses regenerative braking to recapture some of the car's forward momentum without using the brakes.

And any forward momentum captured this way is not absorbed by the brake pads, thus they last much longer.

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