As the basic law of Physics says �energy can neither be created nor be destroyed it can only be converted from one form to another�. During application of the breaks to fast moving vehicle huge amount of energy is lost to atmosphere as heat. It will be good if we could store this energy somehow which is otherwise getting wasted out and reuse it next time we started to accelerate. Regenerative braking refers to a system in which the kinetic energy of the vehicle is stored temporarily,as an accumulative energy,during deceleration,and is reused as kinetic energy during acceleration or running. https://www.ijiert.org/paper-details?paper_id=141253