Recent advances in understanding the capacitive storage in microporous carbons

Barbara Daffos (1) , Pierre-Louis Taberna (1) , Yury Gogotsi (2) , Patrice Simon (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 Department of Materials Science and Engineering and A.J. Drexel Nanotechnology Institute

Specific capacitance as high as 14µF/cm²-160F/g was obtained using well tailored subnanometer pore size activated carbons (6µF/cm²-100F/g for conventional activated carbons). Such high capacitance was obtained in several type of organic electrolyte with or without solvent. It came out a maximum is obtained for those carbons which mean pore size was close to the bare ion size ruling out the traditional point of view that mesoporous carbon are highly required to get the best. Surprisingly subnanometer activated carbons exhibit high capacitance retention since only 10% loss is measured when 6A/g discharge is drawn. These findings show the importance to fit ion size with mean activated pore size. Double layer theory falls short to explain such charge storage mechanisms at nanometer scale thus computational modeling is now currently under progress to find out an other charge storage model.

Mots clés: Physical Sciences

Barbara Daffos, Pierre-Louis Taberna, Yury Gogotsi, Patrice Simon. Recent advances in understanding the capacitive storage in microporous carbons. Fuel Cells, 2010, 10 (5), pp.819. ⟨10.1002/fuce.200900192⟩. ⟨hal-00552370⟩