Capacitance limits of high surface area activated carbons for double layer capacitors
Abstract
A large specific surface area (SSA) of carbon materials used for electrochemical double layer capacitors (EDLC) is the most important parameter leading to a large gravimetric capacitance (C g). However, for a SSA determined with the differential functional theory (DFT) model above a value of 1200 m 2/g the plot of C g versus S DFT exhibits a plateau. We suggest that this limitation of C g can be ascribed to a space constriction for charge accommodation inside the pore walls. As a consequence, the use of extremely high surface area carbons for EDLCs may be unprofitable.
- Publication:
-
Carbon
- Pub Date:
- 2005
- DOI:
- 10.1016/j.carbon.2005.01.001
- Bibcode:
- 2005Carbo..43.1303B
- Keywords:
-
- Porous carbon;
- Activation;
- Adsorption;
- Electrochemical properties