Patent ID: 7907387

Claim:
Electrode comprising a current collector coated on one or two sides with an activated carbon (AC) film, wherein said AC film has the following characteristics: a) porosity: microporous volume (pore diameter <2 nm) determined by the DFT method between 0.5 cm 3 /g and 0.75 cm 3 /g, and representing at least 75 percent of the total porosity of said carbon: BET specific surface area between 1200 and 1800 m 2 /g; b) purity: total ash content, determined by the ASTM D2866-83 method less than 1.5% by weight; the weight percentages of the following impurities, determined by mineralization (HNO 3 /H 2 O 2 treatment) followed by analysis by ICP emission spectrometry or, for chlorides by extraction with water followed by analysis by ion chromatography, are such that: [chlorides]≦80 ppm: [chromium]≦20 ppm; [copper]≦50 ppm; [iron]≦300 ppm; [manganese]≦20 ppm; [nickel]≦10 ppm; and [zinc]≦20 ppm; c) particle size distribution, determined by laser scattering such that: 3 μm≦d 50 ≦15 μm; 10 μm≦d 90 ≦60 μm; d) pH, determined by the CEFIC method between 3.5 and 9, and at least one polymer material, having a thickness less than or equal to 1 mm; and wherein said electrode has the following characteristics in an organic electrolyte: electrode density or density of the film of active material of the electrode greater than or equal to 0.45 g/cm 3 , preferably greater than or equal to 0.5 g/cm 3 ; initial capacitance per unit volume greater than or equal to 47, preferably greater than or equal to 50 F/cm 3 of electrode, measured at 5 mA/cm 2 ; ratio of the capacitance per unit volume after 10 000 cycles, measured at ±5 mA/cm 2 between 0 and 2.3 V, to the initial capacitance per unit volume that is greater than or equal to 0.85, preferably greater than or equal to 0.9; initial surface resistance of the cell (composed of 2 identical electrodes and a separator), measured at 1 kHz, less than or equal to 1, preferably less than or equal to 0.9, and advantageously less than or equal to 0.85 Ωcm 2 ; and ratio of the surface resistance after 10 000 cycles to the initial resistance that is less than or equal to 1.5, preferably less than or equal to 1.3.