Regenerative Braking

Regenerative Braking

Hi. Love the regen braking, maybe have to brake 15-20% of the time. Would like to have a better understanding of the system and its mechanics and would appreciate a resource. I also assume the second set of calipers in rear is for regen. ? If so will they be subject to wear? Thanks.

DFibRL8R | September 12, 2013

2nd set is the parking brake only.

ChristianG | September 12, 2013

As I understand it, the regenerative braking only works over the motor/engine, like you drive with a gear to low and take the foot from the throttle.

the only downside seems to be that if the battery is cold it can't take the energy, therefore the one foot driving doesn't work the first few minutes when driving with a very cold battery pack. So be aware that the braking will not be there everytime.

mrspaghetti | September 12, 2013

It's the motor that does the regen braking.

When you're accelerating, power flows to the motor from the battery and drives the wheels. When decelerating using regen, the wheels are driving the motor (now acting as a generator) and the power goes into the battery.

dtesla | September 12, 2013

All motors can be generators. When you foot is off the accelerator the motor is used as a generator to generate electricity.

mumanoff | September 12, 2013

Thank you one and all. Very helpful.

shop | September 12, 2013

And if you are wondering what part of the motor is applying the friction, the answer is, no physical part. The rotor (the part that is attached to the wheel and spins) gets a magnetic force applied to it from the stator when regenerative braking. The stator is like an electromagnet that wraps around, but doesn't touch, the rotor. So with fancy electronics, magnetism is what slows down the rotor and puts the energy back into the battery. Really cool, nothing to wear out.

NKYTA | September 12, 2013

"Really cool, nothing to wear out"
@shop, except for the tires. ;-)

mrspaghetti | September 12, 2013

Well, to be really nit-picky, electric motors & generators do also have bearings... But they should last a really long time.

Brian H | September 14, 2013

You should be using the brakes about 5% of the time, max.