| 摘要 |
PURPOSE:To obtain an electric double layer capacitor balanced in initial capacitance, internal resistance and low temperature characteristics, by using spherical active carbon particle as the polarizing electrode. CONSTITUTION:Spherical active carbon particle used as polarizing electrodes 1, 2 is obtained by heating bituminous substance like coal tar at 350-500 deg.C; grain diameter is 1-80mum, specific gravity is 1.3-3.2g/cm<3>, ash content is 0.3% or less, and resistivity is 1300-9000muOMEGAcm. This spherical particle is subjected to activation treatment. As to physical property, the following are preferable; specific surface area is 3000-45000cm<2>/g, average fine hole diameter is 10-15Angstrom , volume ratio of fine holes having a fine hole diameter of 20Angstrom or more to the total fine whole volume is 20-60%. Electrodes 1, 2 are formed by using bonding agent excellent in resistance to chemicals such as polytetrafluoroethyrene and turning the active carbon powder into a sheet. |
