I tried a simple experiment this morning. Starting from the same stopping point going about 55 mph before the stop sign, I tried two different methods to stop.
- Lifting my foot off the accelerator with the car in Drive about 0.4 miles before the stop sign then using the brake as I approached the stop sign. Regen occurred slowly over a long period of time.
- Shifting the car into neutral until I got closer to the stop sign (to stop consuming/adding energy from/to the HVB), then shifting into Low to brake, and then shifting back to neutral, and eventually back to drive and applying the brake. Regen occurred rapidly over a short period of time.
With the slow regen method, the motor/generator produced 0.0761 kWh of electricity. With the fast regen method, the motor/generator produced 0.0896 kWh of electricity. For fast regen method, the motor/generator produced 18% more electricity. This takes into account the power used by the car's accessories.
With the slow regen method, the car claims that 0.062 kWh of energy was added to the HVB. With the fast regen method, the car claims that 0.078 kWh of energy was added. However, the slow regen method took much longer than the fast regen method. The car's accessories used twice as much energy during the slow regen method than the fast regen method. Taking that into account, the fast regen method added 19% more energy to the HVB.
So it appears to make a difference in the amount of regen for slow vs. faster braking. You can get about 18-19% more regen with faster braking if you do it right. However, if you continue to press the accelerator to maintain the car's momentum until the last possible moment, and then brake at the maximum charge limit, you probably won't realize much, if any, of the 18-19% additional regen. It may be wiped out by the additional time you were using energy by applying the accelerator.
Note that you don't want to apply the brakes when the car is in neutral. You will get no regen from the brakes driving in neutral.
One would have to experiment a lot more to determine the optimal braking strategy for various situations.
Edited by larryh, 26 April 2014 - 05:59 AM.