Is regenerative braking affected by the larger battery?
The PHEV conversion has no effect on how much energy can be recovered from braking during normal driving. Yet, regenerative braking is not as impressive in a PHEV: because the PHEV battery can hold so much more energy than the standard HEV battery, the energy from regenerative braking from normal driving is a small portion of the energy in the pack. However, when coming down a long, big hill, the battery in a PHEV may be able to keep on taking energy from regenerative braking for a long time (about 1-1/2 hours), unlike the battery of an standard HEV, which is quickly filled.