To produce an active carbon fiber and an active carbon fiber cloth good in volume resistivity, density and specific surface area suitable for an electric double layer capacitor according to a simple process at a low cost.
The active carbon fiber or active carbon fiber cloth is produced by baking a cellulosic fiber or its woven cloth together with calcium carbonate containing magnesium carbonate at ≥800°C at ≤10°C/h heat-up rate for ≥1 weeks. Otherwise, the active carbon fiber or active carbon fiber cloth is produced by dipping the cellulosic fiber or its woven cloth in an aqueous solution of a phosphoric salt or an aqueous boric acid and baking the dipped cellulosic fiber or woven cloth according to the same method or dipping the cellulosic fiber woven cloth in water or the same aqueous solution, hot pressing the dipped cellulosic fiber or woven fabric and then baking the hot pressed cellulosic fiber woven cloth by the same method. According to the method, the active carbon fiber cloth having ≥0.2 g/cm3 density, ≤0.2 Ωcm volume resistivity and ≥900 m2/g specific surface area is produced and a sufficient capacity usable as a carbon sheet for an electric double layer capacitor is obtained.
MASUKO TSUTOMU
NANBA YOICHI
MAETA KAZUNORI
Next Patent: STRUCTURE USING NET MATERIAL, SHEET AND END PART TREATING OF NET MATERIAL