In a current collector laminating step, a current-collector laminate unit 30 composed of current-collector materials 31 and 32 and a film material 33 is formed. Resist layers 34 having a predetermined pattern are formed on both surfaces of the current-collector laminate unit 30. An etching process is performed with the resist layers 34 used as a mask, whereby through-holes 20a and 23a are formed on the respective current-collector materials 31 and 32. The resist layers 34 are removed from the current-collector laminate unit 30. Since the etching process is performed on the plural current-collector materials 31 and 32, productivity of an electrode can be enhanced. During the application of the slurry, the film material 33 prevents the leakage of the electrode slurry. Therefore, the current-collector laminate unit 30 can be conveyed in the horizontal direction, whereby the productivity of the electrode can be enhanced.