Electrochemical performance of supercapacitor with stacked copper foils coated with graphene nanoplatelets

• Main Authors: Chiam, S. L., Lim, Hong Ngee, Syed Mohd Jaafar, Syed Muhammad Hafiz, Pandikumar, Alagarsamy, Huang, Nay Ming
• Format: Article
• Language: English
• Published: Springer 2018
• Online Access: http://psasir.upm.edu.my/id/eprint/72544/1/Electrochemical%20performance%20.pdf; http://psasir.upm.edu.my/id/eprint/72544/; http://www.ukm.my/fep/jem/content/2018-2.html
• Institution: Universiti Putra Malaysia

The energy density of conventional supercapacitors is in the range of 6–10 Wh kg−1, which has restricted them from many applications that require devices with long durations. Herein, we report a method for enhancing the energy density of a device through the parallel stacking of five copper foils coated on each side with graphene nanoplatelets. Microporous papers immersed in 2 M aqueous sodium sulphate were used as separators. With a low contact resistance of 0.05 Ω, the supercapacitor yielded an optimum specific energy density and a specific power density of 24.64 Wh kg−1 and 402 W kg−1 at 0.8 V, respectively. The working potential was increased to 2.4 V when three of the supercapacitors were connected in series, forming a tandem device. Its potential for real applications was manifested by the ability to light up a light-emitting diode for 40 s after charging for 60 s.