The present invention provides a method of making an electrochemical
capacitor electrode including a collector and an electronically
conductive porous layer formed on the collector, the porous layer
containing at least an electronically conductive porous particle and a
binder adapted to bind the porous particle; the method including a mixing
step of mixing the binder and a porous particle with a solvent including
an organic solvent usable in a nonaqueous electrolytic solution, the
organic solvent existing on a surface of the porous particle. The present
invention also provides a porous particle with a solvent, wherein an
organic solvent usable in a nonaqueous electrolytic solution exists on
the surface of a porous body having an electronic conductivity.