ALL-SOLID TYPE ELECTRIC DOUBLE-LAYER CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide an all-solid type electric double-layer capacitor which is high in electrostatic capacitance, capable of downsizing and small in frequency dependence of the electrostatic capacitance.SOLUTION: Disclosed is an all-solid type electric double-layer capacitor including an inorganic solid electrolyte and a pair of current collectors provided holding the inorganic solid electrolyte. The inorganic solid electrolyte contains a plurality of ion conductive crystal particles made of a first crystal phase, and a particle boundary phase which exists among a plurality of ion conductive crystal particles and is composed of a second crystal phase different from the first crystal phase or an amorphous phase. The ratio T/D of the average thickness T of the particle boundary phases to the average particle diameter D of the ion conductive crystal particles is 0.15 or more.