Adaptive Real-Time Energy Management of Battery-Supercapacitor Hybrid Storage Systems for Electric Vehicles Under Standard Driving Cycles

The increasing demand for high-performance electric vehicles (EVs) has highlighted the limitations of lithium-ion (Li-ion) batteries in handling high transient power demands associated with rapid acceleration and regenerative braking. High current fluctuations reduce battery efficiency and its lifespan. To mitigate this challenge, we present an adaptive energy management strategy (EMS) for a battery-supercapacitor hybrid energy storage system (HESS) to improve power distribution and reduce battery stress under dynamic driving conditions. The proposed method integrates lithium-ion batteries as the primary energy source with a supercapacitor as a secondary high-energy storage device. The developed adaptive rule-based EMS allows for the real-time distribution of energy between the lithium-ion battery and supercapacitor, considering the load demand, the energy status of supercapacitors, and operational constraints.The proposed method is validated in a WLTP driving cycle using an advanced electric vehicle longitudinal dynamics model, which provides a more accurate representation of actual driving conditions. Furthermore, an offline dynamic programming framework is implemented as a globally optimal benchmark to enhance comparison and offer a stronger performance analysis. The advanced EMS is evaluated based on a number of performance metrics that include peak battery current, RMS battery current, battery state-of-charge depletion, supercapacitor utilization, voltage control, and power-sharing characteristics.Simulation results demonstrate that the proposed HESS significantly reduces battery current stress by shifting transient power demands to the supercapacitor during acceleration and absorbing regenerative braking energy during deceleration.