Supercapacitor Peukert Constant During a Constant Power Discharge Process

This paper examines the supercapacitor Peukert constant during a constant power discharge process. Recent studies show that the energy delivered by a supercapacitor during a constant power discharge process increases when the discharge power decreases if the discharge power is above a certain threshold, i.e., Peukert's law applies. This paper investigates the dependence of the supercapacitor Peukert constant on the initial voltage, cutoff voltage, and voltage difference of the constant power discharge process by testing two supercapacitor samples. The physical mechanisms leading to the Peukert constant dependence are revealed by analyzing a physics-based RC ladder circuit model for supercapacitors.