A method is provided for optimizing the physical characteristics of a coating solution for a polarizable electrode layer formed on a collector. A first step is carried out to prepare a coating solution that includes porous particles, a fluorine-based binder, a good solvent that dissolves said fluorine-based binder, and a poor solvent that does not dissolve said fluorine-based binder. A second step is carried out to coat a collector with said coating solution to form the polarizable electrode layer on the collector. The viscosity of said coating solution for the polarizable electrode layer is set to between 0.5 to 3.5 Pa·s and a weight ratio (GS/PS) of said good solvent (GS) and said poor solvent (PS) is set to between 60/40 to 80/20. The occurrence of cracks in the polarizable electrode layer and large nonuniformities in the thickness of the polarizable electrode layer can thus be prevented.