A high energy density flexible solid-state supercapacitor based on poly (arylene ether sulfone) copolymers with polyether side chains for Li+ conducting polymer electrolytes

To satisfy the market demand for excellent electrochemical performance, a flexible gel polymer electrolyte (GPE-EO) based on poly(arylene ether sulfone) copolymers containing polyether side chains (PAES-EO) was prepared via an ion-exchange reaction with ammonium poly(aryl ether sulfone) (PAES-N) and PEG–SO3–K+ containing EO segments. Li2SO4 was used as the electrolyte salt for the supercapacitor to obtain a wider potential window (1.5 V) and the electrochemical performance of the supercapacitors based on polymer electrolytes with or without EO segments was evaluated and analysed. With the introduction of EO segments, the electrolyte uptake ratio of the electrolyte membrane increased to 53.29% and delivered a higher ionic conductivity of 8.26 × 10−4 S cm−1. The supercapacitor based on GPE-EO exhibits a high capacitance of 153.8 F g−1 and an energy density of 11.67 W h kg−1 at a current density of 0.1 A g−1. Simultaneously, this supercapacitor based on GPE-EO possessed excellent flexibility even at a bending angle of 180° and outstanding cycle stability with negligible specific capacitance loss after 5000 cycles. This improvement of performance of gel polymer electrolytes and supercapacitors demonstrates that introducing EO segments can increase the electrochemical performance of PEAS based energy storage devices.