The present invention aims to provide a method for bonding protective tapes to the cut edges of an electrode plate within a short period to prevent short circuit in an electrode assembly. An electrode plate cutting & tape bonding process includes (1) cutting an electrode plate into pieces 100a and 100b, (2) forming a gap W between edges 106 and 107 of the pieces 100a and 100b, (3) bonding protective tapes 51 and 52 to both sides of the pieces 100a and 100b, covering the edges and the gap, and (4) conveying the pieces 100a and 100b connected together. Next, the tapes 51 and 52 are cut into pieces 51a & 52a and 51b & 52b. Then, the electrode plate piece 100a with the tape pieces 51a & 52a and 51b & 52b is wound together with a negative electrode plate, with a separator sandwiched therebetween.