Alumina's Effect as Blocking Layer on Self-discharge Process: Case Study of Supercapacitors as Energy storage Devices

• Published in: 2019 IEEE PES/IAS PowerAfrica pp. 470 - 475
• Main Authors: Salami, Adekunle Akim, Kodjo, Koffi M., Boureima, Seibou, Guenoupkati, Agbassou, Dotche, Koffi Agbeblewu, Bedja, Koffi-Sa
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-08-2019
• Subjects: alumina; Aluminum oxide; Capacitance; Electrodes; Electrolytes; faradic reactions rate; leakage current; Mathematical model; Permittivity; self-discharge; Supercapacitors; supercapacitors modelling
• DOI: 10.1109/PowerAfrica.2019.8928900

Supercapacitors are useful in peak power applications to suppress and compensate transient effects that significantly affect batteries. Unfortunately, they suffer from self-discharge due to the redox reactions process in porous electrodes. This study aims at investigating into the effect of Alumina (Al 2 O 3 ) as insulating layer (blocking layer) on the supercapacitors' performance during the self-discharge phenomenon. Two models of supercapacitors were developed, and implemented in the Matlab/Simulink software. The first model is without, and the second one with Al 2 O 3 coating. Some simulations are performed. The results demonstrate that an application of an ultra-thin insulating layer of Al 2 O 3 with a thickness about 0.5 nm on the electrodes of supercapacitors may reduce the faradic reactions rate by 17% and the leakage current by 77.73%. However, the specific capacitance of the electrical double layer may decrease by 45.35% and the voltage drop is about 50% for devices without Al 2 O 3 compared to 0.02% with Al 2 O 3 .