Integrated Modeling Strategy of Regenerative Braking and Battery Degradation in Electric Vehicles Using Real-World Driving Cycles

Regenerative braking System (RBS) effectively captures the kinetic energy lost during braking, thereby increasing the range of vehicles. It presents a critical trade-off between the immediate charging to increase the cycle life and the degradation in long-term battery life. This research proposes a model which integrates the regenerative braking model and battery degradation model. This integrated approach combines the simulation benefits of immediate energy recovery and the long-term impact on battery degradation under real-world driving conditions. The objective is to analyse the parameters such as state of charge (SOC), state of health (SOH), efficiency, regenerative torque and braking intensity. Literature gap is addressed by a novel integrated modelling validated by the real-world driving cycle data generated by an experiment conducted on a 3.7 kWh electric two-wheeler driven across urban, rural and highway conditions, making this approach on battery analysis representative of an actual electric vehicle usage, unlike the models based on standard procedures. Four different driving cycles were used for simulation, which are the Indian Driving Cycle (IDC), Federal Test Procedure-75 (FTP75), Urban Dynamometer Driving Schedule (UDDS) and a real driving cycle generated by the experiment. For the cycle life, the results show the benefit of RBS in immediate energy recovery, an improvement of 4% SOC for IDC in one cycle, and the highest recovery of 4 kW compared to FTP75 and UDDS. The efficiency throughout the cycle reached a peak of about 40%. For the long term, IDC showed the most decline to about 70% SOH and FTP75, and the real driving cycle showed the maximum rate of increase in internal resistance. Hence, this research shows that while RBS provides immediate benefits, the frequent charging and discharging profiles will result in a faster degradation of the battery health in the long term in electric vehicles.