High‐Voltage Supercapacitors Based on Aqueous Electrolytes

Supercapacitors with high power density and life cycles are an important family of power supplies among energy storage systems. The operating voltage window of a supercapacitor is determined by both the chemistry of electrode materials and the electrochemical kinetics of electrolytes while the water hydrolysis potential of 1.23 V is the typical limit for capacitors based on aqueous electrolytes. Here, we briefly outline the working mechanism of...