Integrating perovskite materials and bamboo-based activated carbon for electrochemical energy storage in hybrid supercapacitors

Electrochemical devices such as fuel cells, lithium-ion batteries, and supercapacitors have become vital emerging technologies for conserving, storing, and transferring energy. Electrochemical supercapacitors are an alternative for energy storage devices that can satisfy the demand for a high-power supply and long cycling life. However, the low energy density and high manufacturing cost are issues that limit their further development. Here, we report the innovative integration of perovskite (LSMO, BTO, and PZT) and bamboo-based activated carbon (BAC) materials deposited in a thin layer by the spray pyrolysis technique to hybridize the double-layer electrode and the electroactive medium in electrochemical supercapacitors. Different supercapacitor configurations, in the form of asymmetric coin cells using organic cellulose and cotton lint as separators, were assembled and tested to investigate their dynamic electrical behavior and performance for power applications through cyclic voltammetry, galvanostatic charge/discharge profiling, electrochemical impedance spectroscopy, and modeling of the experimental data. The fabricated supercapacitor device with BTO/cellulose achieved the specific capacitances of 300 F/g, energy densities of 6.7 Wh/kg, power densities of 600 W/kg, and maintained >95 % of the initial capacitance after several charge/discharge cycles. Based on these promising properties, two identical supercapacitor cells were arranged in series and used to power a yellow LED for several minutes, confirming that our supercapacitor approach exhibits potential for practical applications. This work will facilitate the realization of more flexible, light, and inexpensive supercapacitors with the potential for long life and capable energy-storing performance.