Superior Charge‐Discharge Performances in High‐Entropy Polymers

Abstract Polarization and depolarization in response to an external electric field describe the charge and discharge behavior of dielectric materials characterized by high power densities, large discharged energy densities, and fast discharged rates, which finds wide applications in modern electrical and electronic systems. Here a giant power density of 3607.5 MW cm −3 together with an ultrahigh discharged energy density of 30.1 J cm −3 and an ultrafast discharge rate of 10.6 ns are achieved in the high‐entropy relaxor ferroelectric terpolymers at 500 MV m −1 , which markedly outperforms dielectric polymers and ceramics under the same load resistance. The superior charge‐discharge performance is mainly attributed to the formation of a high‐entropy state with greatly enhanced dielectric constant and ultrahigh capacitive ability. This work paves the way for future exploration of high‐entropy polymers with enhanced functionalities.