NOVELTY - The pack has multiple battery cells that are connected by a bus-bar (3) which is a metal clad material (30) formed by joining a first metal plate (31) consisting of aluminum plates, and a second metal plate (32). The first metal plate has an insertion groove (35), and the second metal plate has an insertion protrusion portion (36) inserted in the insertion groove. The bus-bar on the clad boundary (33), exposes an outside wall (37) of the insertion groove to bus-bar both surfaces, and provides a plated layer (34) in surface of the second metal plate.    USE - Battery pack for e.g. electrical storage apparatus and electric vehicle (all claimed) such as plug-in type hybrid electric vehicle, plug-in hybrid motor vehicle, and hybrid type electric vehicle. Can also be used in e.g. in rack of computer server, wireless base stations such as mobile telephone, home internal, and as power supply for e.g. household use, factories and street lights, and as backup power supplies with solar cell for e.g. signal apparatus.    ADVANTAGE - Since the outside wall of the insertion groove of the first metal plate is exposed on bus-bar both surfaces, and the plated layer is provided in the surface of the second metal plate, the bus-bar consisting of the clad material of this structure is exposing the aluminum plate in that surface, arranging both the metal plates which becomes a clad boundary from the aluminum plate. Hence the surface area of the second metal plate is large in the surface area which the aluminum plate exposes, and the surface area of aluminum is not made small. The area of the plated layer plated onto the surface of the second metal plate can be made small. Since the area of the plated layer can be made small, plating cost is reduced and the high production of the bus-bar can be carried out to low cost. There is much number of objects used for each battery cell for making the cell serial, and reducing manufacturing cost and the bus-bar is effective in the ability to reduce the manufacturing cost of the battery pack fairly. Thus the battery pack has the characteristics which can connect the battery cell in series stably by the bus-bar, reducing the manufacturing cost of the bus-bar and enlarging charging capacity with respect to volume and weight by using the battery cell.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) an electric vehicle; and    (2) an electrical storage apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of the bus-bar.    Bus-bar (3)    Metal clad material (30)    Metal plates (31,32)    Clad boundary (33)    Plated layer (34)    Insertion groove (35)    Insertion protrusion portion (36)    Outside wall of the insertion groove (37)