“…Supercapacitors are an important class of electrochemical energy storage device, they possess the characteristics of high power density, fast charge/discharge rate, excellent cycling life, low cost, and safe operational conditions. [293][294][295][296] However, they present a low energy density, limiting the optimal discharge time to less than a minute, whereas many applications clearly require more. 293,297,298 Therefore, one of the challenges posed for supercapacitors is to increase energy density without compromising power density, or, alternatively, to achieve a proper balance between the two.…”