NOVELTY - The cell assembly (M1) has a stacked-type secondary cell provided with an exterior case (11) for housing an electrode group, external terminals (11fa,11fb) provided to opposing surfaces on both sides of the case, and a cover member for sealing an open part of the case. A joint (21a-21d) between the case and cover member is provided to protrude outward from an external peripheral edge of the case. A linking member (7,7A) is interposed to hold the joint on a top level and joint on a bottom level. The joints are stacked vertically in the stacking direction of secondary cells (RB1-RB4).    USE - Cell assembly used in a battery system (claimed). Uses include but are not limited to lithium secondary cells used in applications having small size and weight i.e. used as power supply cells for mobile telephones, notebook-type personal computers, and other portable electronic devices, and lithium secondary cells with high capacity, and used as motor drive power supplies for electric vehicle (EV), hybrid electric vehicle (HEV) and as storage cells for power storage. Can also be used in a battery system for home use, such as battery system installed outdoors, such as under eaves, under a window.    ADVANTAGE - Provides a compact battery system having a small depth and height, and in which connection, wiring, and other electrical work can be easily performed. Linked configuration is obtained in which the height in the stacking direction can be minimized since the secondary cells stacked vertically is linked together via linking members for holding together the joints, which protrude on the sides of the cell canisters, the secondary cells can therefore be stacked and assembled with a compact height, and a cell assembly can be obtained in which the single cells can be securely fixed in place without becoming misaligned with each other. The use of the linking members enables compact assembly in the transverse direction as well, provides electrical safety, and facilitates wiring connection in the cell assembly since the linking members are provided with gap parts for containing the external terminals and the terminal connecting member and the linking members have a retention function of holding the stacked secondary cells, an electrical function of placing the circuit unit in a position away from the cell canisters, and a protective function of containing and protecting the external terminals, the terminal connecting member for connecting upper and lower external terminals to each other, and other components. The electrical connections can be made on the sides of the cell canisters since the external terminals are provided on the sides of the cell canisters, and the stack can be made compact in the height direction, making it possible to obtain a cell assembly in which the secondary cells can be compactly linked, the single cells can be securely fixed in place so as not to become misaligned with each other, and wiring connection is facilitated.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a battery system.    DESCRIPTION OF DRAWING(S) - The drawing shows the rough sectional view of the cell assembly.    Linking member (7,7A)    Exterior case (11)    External terminals (11fa,11fb)    Joint (21a-21d)    Cell assembly (M1)    Secondary cells (RB1-RB4)