A superior electrolyte composite with high conductivity and strength based on alkali-activated slag and polyacrylamide for structural supercapacitor

In the time to come, structural supercapacitors have broad prospects in large-scale and construction structure energy storage. But the contradiction between ionic conductivity and mechanical performances of structural electrolytes still exists. Here, a novel polyacrylamide/alkali-activated slag (PAM/AAS) structural electrolyte composite is reported to attain a balance of high ionic conductivity and qualified compressive strength. The prepared PAM/AAS composite structural electrolytes show optimal properties with ionic conductivity of 55.01 mS/cm and compressive strength of 44.5 MPa in the dry state and 36.9 MPa after soaked in aqueous solution of 2 M KOH. Structural supercapacitor assembled with rGO electrodes has high mass specific capacitance of 285.35 F/g at 1 mA/cm2, energy density of 2.48 Wh/kg and power density of 59.54 W/kg, and favorable cycle life. The results of PAM/AAS composite structural electrolytes are superior to those in latest researches, attesting its vast application potential in construction structure energy storage. •The PAM/AAS electrolyte composites show superior ionic conductivity without obvious strength loss.•Assembled supercapacitors exhibit outstanding specific capacitance, high energy and power density.•Considerable cyclic reversibility of assembled supercapacitors over 5000 cycles.