High-Mass Loading Hierarchically Porous Activated Carbon Electrode for Pouch-Type Supercapacitors with Propylene Carbonate-Based Electrolyte.

Rational design and development of the electrodes with high-mass loading yet maintaining the excellent electrochemical properties are significant for a variety of electrochemical energy storage applications. In comparison with the slurry-casted electrode, herein, a hierarchically porous activated carbon (HPAC) electrode with higher mass loading (8.3 ± 0.2 mg/cm2) is successfully prepared. The pouch-type symmetric device (1 cell) with the propylene carbonate-based electrolyte shows the rate capability (7.1 F at 1 mA/cm2 and 4.8 F at 10 mA/cm2) and the cycling stability (83% at 12,000 cycles). On the other hand, an initial discharge capacitance of 32.4 F and the capacitance retention of 96% after 30,000 cycles are delivered from a pouch-type symmetric supercapacitor (five cells). The corresponding electrochemical performances are attributed to the fascinating properties of the HPAC and the synergistic features of the resulting electrode.