Investigation on EDLC in Aqueous Electrolyte for Application to Coin-Cell Type Storage Batteries

Abstract:

Activated carbon plays an important role in improving the performance of Electric Double Layer Capacitors (EDLCs), and research has been conducted on controlling the pore structure of activated carbon, which has a very high specific surface area. However, breakthroughs in electrodes have been difficult to achieve by pore control alone. In this study, specific capacitance, internal resistance, energy density, and power density of coin cell electrodes were calculated from electrochemical measurements using basic activated carbon, and their characteristics were evaluated. As the results, it showed the performance increased. This is thought to have been influenced by the increase in hydrophilicity due to the basicity of the activated carbon surface. It can be concluded that the increase in hydrophilicity is related to the increase in surface area contributing to the adsorption of ions due to improved electrolyte leakage during the charging and discharging process, resulting in the observed improvement in performance.

• Periodical: Materials Science Forum (Volume 1150)
• Pages: 85-91
• DOI: https://doi.org/10.4028/p-vXfuN9
• Online since: June 2025
• Authors: Shuto Kobayashi, Yuki Nishiyama, Daisuke Tashima*
• Keywords: Basic Activated Carbon, Charge Transfer Resistance [Ω], Electric Double Layer Capacitors, Energy Density [Wh/kg], Power Density [W/kg], Specific Capacitance [F/g]

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