Chevy Bolt EV Forum banner

41 - 44 of 44 Posts

·
Registered
Joined
·
4,219 Posts
my impression is that the brake pedal only slows using the brake pads. it does not cause any regen.
Note true. Watch the power meter on the right side of the Driver Information Console while going down a hill in "D" mode - as you press the brake pedal you'll see the regen ramping up.

I did an unscientific test going down a long hill in "L" mode and then again in "D" mode. I couldn't notice any significant difference in regen power between the two as reported on the Driver Information Console. I suspect that the brake pedal will generate pretty much the same levels of regen as "L" mode does before engaging the hydraulic brakes.

In terms of efficiency, then, the main benefit of using "L" mode (aside from the fact that it's a very cool and intuitive way to drive) is that in "L" mode you know for sure that there is no hydraulic braking involved if you don't press the brake pedal. In "D" mode you might be wasting some momentum to friction braking if you hit the brake pedal a little too hard.
 

·
Registered
Joined
·
3,429 Posts
I know that 'jack rabbit' starting uses more power than slower acceleration. But the opposite of that would be that rapid deceleration would produce more regen power than slowly coming to a halt. So I drive in L and try to maintain my speed as close as I can to where I have to stop and then take my foot off the 'gas' and press the regen paddle to slow down as fast as I can (and if I stop short, no big deal).
From a physics standpoint, it takes exactly the same amount of energy to accelerate something to a given speed quickly or slowly. In an ICE vehicle, it's most efficient to be at about 80% of peak torque at around 2500 RPM.

Electric motors have a peak range of efficiency too, but they have such a broad range of "good" that it kinda doesn't matter. A fast start vs slow doesn't really affect range much.

Likewise, there is a peak efficiency for regen as well, but that too doesn't matter so much.

If you're really concerned with peak efficiency, the #1 thing is to drive slower. Avoiding use of regen/brakes is the next driving behavior to maximize range.
 

·
Registered
Joined
·
1,706 Posts
... backup reference...

 

·
Registered
Joined
·
79 Posts
Discussion Starter #44
I did an unscientific test going down a long hill in "L" mode and then again in "D" mode. I couldn't notice any significant difference in regen power between the two as reported on the Driver Information Console. I suspect that the brake pedal will generate pretty much the same levels of regen as "L" mode does before engaging the hydraulic brakes.
That is basically what I noticed when I took 2020 for a test drive.
Sure, it was only 3 mile in city, but for similar deceleration rate (felt by my butt dyno) numbers were about same. The only difference was coming to a complete stop where in L it would sit, in D would creep...
 
41 - 44 of 44 Posts
Top