Can distinguishing regenerative braking signal in electric vehicles improve following-vehicle safety?

The rapid adoption of electric vehicles (EV) introduces a safety concern regarding regenerative braking, which often causes significant deceleration without activating traditional brake lights. This can lead following drivers to be unable to timely perceive abrupt deceleration, increasing the risk of collisions. To address this gap, this study investigated the effects of a novel brake light system (one that distinguishes between friction and regenerative braking using red and green lights) on the driving behaviors and perceptions of following drivers. We designed and conducted a within-subject driving simulator study with 24 young drivers. The results showed that the new system led improved driving maintenance performance, enhanced braking behavior efficiency, reducing the number of brake pedal pressures and foot transitions. Further, drivers provided better subjective evaluations, reporting lower workload (NASA-TLX), higher usability (SUS), and increased trust. It can be concluded that newly suggested braking light system for regenerative braking can mitigate driver fatigue and improve perceived safety when following EVs.