A battery pack comprising a plurality of battery modules (BM, BM1, BM2, BM3, BM4, BM5, BM6), the plurality of battery modules (BM, BM1, BM2, BM3, BM4, BM5, BM6) connected in series to each other, the plurality of battery modules (BM, BM1, BM2, BM3, BM4, BM5, BM6) each including a plurality of battery cells, a battery cell holder, a first-electrode assembly, a second-electrode assembly, and a cover (18, 22), the battery cell holder holding the plurality of battery cells, the first-electrode assembly including a plurality of first-electrode bus bar plates, a first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6), a second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6), and an inter-electrode bus bar, the second-electrode assembly including a plurality of second-electrode bus bar plates, the plurality of first-electrode bus bar plates each electrically connecting first electrodes of two or more of the plurality of battery cells to each other, the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) connected to one of the plurality of first-electrode bus bar plates, the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) connected to one of the plurality of second-electrode bus bar plates, the inter-electrode bus bar connecting the second-electrode bus bar plate and one of the first-electrode bus bar plate and the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6),the plurality of second-electrode bus bar plates each electrically connecting second electrodes of two or more of the plurality of battery cells to each other, the cover (18, 22) covering at least a part of the battery module (BM, BM1, BM2, BM3, BM4, BM5, BM6), wherein the first-electrode assembly is in one of a first pattern and a second pattern, the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) and the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) are arranged in a first arrangement in the first pattern, and the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) and the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) are arranged in a second arrangement in the second pattern, the second arrangement being different from the first arrangement, and an arrangement of the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) and the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) in the battery module (BM, BM1, BM2, BM3, BM4, BM5, BM6) differs according to the pattern of the first-electrode assembly used in each of the plurality of battery modules (BM, BM1, BM2, BM3, BM4, BM5, BM6). the battery cell holder holding the plurality of battery cells, the first-electrode assembly including a plurality of first-electrode bus bar plates, a first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6), a second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6), and an inter-electrode bus bar, the second-electrode assembly including a plurality of second-electrode bus bar plates, the plurality of first-electrode bus bar plates each electrically connecting first electrodes of two or more of the plurality of battery cells to each other, the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) connected to one of the plurality of first-electrode bus bar plates, the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) connected to one of the plurality of second-electrode bus bar plates, the inter-electrode bus bar connecting the second-electrode bus bar plate and one of the first-electrode bus bar plate and the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6),the plurality of second-electrode bus bar plates each electrically connecting second electrodes of two or more of the plurality of battery cells to each other, the plurality of first-electrode bus bar plates each electrically connecting first electrodes of two or more of the plurality of battery cells to each other, the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6) connected to one of the plurality of first-electrode bus bar plates, the second-electrode terminal (TN, TN1, TN2, TN3, TN4, TN5, TN6) connected to one of the plurality of second-electrode bus bar plates, the inter-electrode bus bar connecting the second-electrode bus bar plate and one of the first-electrode bus bar plate and the first-electrode terminal (TP, TP1, TP2, TP3, TP4, TP5, TP6),the plurality of second-electrode bus bar plates each electrically connecting second electrodes of two or more of the plurality of battery cells to each other, the cover (18, 22) covering at least a part of the battery module (BM, BM1, BM2, BM3, BM4, BM5, BM6),