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EVDRIVER
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Re: Response to EPA FOIA Request

Mon Jan 24, 2011 7:44 pm

To achieve higher regen one needs to have more off pedal regen if they wish to keep the regen/brake gap smooth in the way Nissan desired. That is a very simple explanation of a more complex way they did this to make it feel as car like as possible. If they made it more like an EV things would be different in many ways but they were afraid of offending average drivers. If the LEaf had higher regen the front brake rotors would rust. My EV had a regen cut switch so one could seat the brake pads once in a while because they never bound to the rotors and they were always rusted. Check your rotors after time, if they are clean they are being used too much. In the ebox one can come to a high speed stop without touching the brake rotor at all until about 2 mph when the field brakes in the motor. If the LEAF rotors get warm or hot then that's a sad sign for an EV.

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DaveEV
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Re: Response to EPA FOIA Request

Mon Jan 24, 2011 10:28 pm

EVDRIVER wrote:If they made it more like an EV things would be different in many ways but they were afraid of offending average drivers.
I highly doubt it. They would simply always apply some friction brakes at very low speeds (below 5mph) like the Prius. It only takes a bit of braking at less than parking lot speeds to wipe off surface rust. And since they greatly limit regen with the battery full the first stop at your corner stop sign would wipe every thing nice and clean for the rest of the trip. Or if you only charge to 80% - just program the car to use friction brakes a bit more for the first couple brake applications. Problem solved.

Stop spreading FUD and making stuff up.

Herm
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Re: Response to EPA FOIA Request

Sat Apr 30, 2011 8:38 am

I believe GM is using some sort of rust resistant coating on the Volt's rotors. Why cant they use stainless steel (perhaps a special alloy that is somewhat rust resistant and can handle heat) or aluminum for the rotors?

Nissan can blend in as much regen to the friction brakes as they want, and still retain a mechanical failsafe and good brake pedal feel.. you step on the pedal, the piston in the master cylinder moves but the hydraulic pressure is shunted off with a failsafe electronic valve while the big drive motor takes care of the regen braking. A small motor pushes back on the brake pedal to fool you :)

I dont know how Nissan does it but that sounds like the logical simple way to do it. Mechanical failsafe braking must be retained no matter what.

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