TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Module: The positive electrode terminal of the one unit cell and the negative electrode terminal of the adjacent unit cell face each other in the one direction. The positive electrode terminal and negative electrode terminal have a plane surface parallel to a side surface of the unit cells, and the plane surfaces face the one direction. The positive electrode terminal includes a positive electrode through-hole passing through it, and the negative electrode terminal includes a negative electrode through-hole passing through it and corresponding to the positive electrode through-hole. The positive electrode terminal and the negative electrode terminal are coupled to each other by a first member inserted in and passing sequentially through the positive electrode through-hole and the negative electrode through-hole and by a second member coupled to the first member. The spacer is a hollow cylinder with spacer ends with the first member passing through it, and where the spacer ends electrically connect to the plane surface of the positive electrode terminal and the facing plane surface of the negative electrode terminal. Preferably, the spacer and the first member are coupled by screw threads. The spacer includes a flange on each end of the cylinder through which flanges the first member passes, and the flanges are electrically connected to one plane surface of the positive electrode terminal and to one plane surface of the negative electrode terminal that face each other. The flanges include a protrusion protruding toward the plane surface of the positive electrode terminal and the negative electrode terminal around the positive electrode through-hole and the negative electrode through-hole, respectively. The spacer is in the form of a clip elastically coupled to the first member, the clip having clip ends, and where the spacer electrically connects the clip ends to the plane surface of the positive electrode terminal and the plane surface of the negative electrode terminal. The spacer is in the form of one of a cylindrical pipe and a polygonal pipe with an opening in a lengthwise direction. The spacer has spacer ends, the positive electrode terminal has a positive electrode groove at the plane surface to receive at least a portion of one of the spacer ends, and the negative electrode terminal has a negative electrode groove at the plane surface facing the positive electrode groove to receive at least a portion of another of the spacer ends. The positive electrode groove and the negative electrode groove are in the form of one of an electrode groove circle and an electrode groove polygon, and the spacer is in the form of one of a circular spacer cylinder or a spacer polygon corresponding to the form of one of the electrode groove circle and the electrode groove polygon. The spacer ends are wholly inserted in the positive electrode groove and the negative electrode groove. The positive electrode through-hole is spaced from the unit cell with respect to the positive electrode groove, and the negative electrode through-hole is spaced from the unit cell with respect to the negative electrode groove.