NOVELTY - The cell has pair of collector plates which are arranged on the flat portion in the outermost surface of core exposed portion (5b) of electrode plate so that pair of collector plates sandwich the flat portion along the thickness direction. The columnar connection conductive element is interposed between the two-divided core exposed laminates (12') in the flat portion which is sandwiched between the pair of current collector Plates. The pair of collector plates, conductive element and laminates are welded to each other.    USE - Prismatic sealed secondary cell such as lithium ion secondary cell used in electric vehicle/hybrid electric vehicle such as cell-powered car, mobile electronic devices such as mobile phone and laptop computer. Can also be used in nickel-hydride and nickel-cadmium cells.    ADVANTAGE - The two-divided core exposed laminates can be electrically connected with the each other by performing a welding process when the exposed core portion laminate is divided into two groups and conductive element is interposed between the two-divided core exposed laminates hence the welding workability can be improved while improving the welding quality. The current collection efficiency and current collection stability, and reliability of high capacity prismatic sealed secondary cell can be improved at low cost. The prismatic sealed secondary cell can output high current. The width of core exposed portion can be reduced. The convex curve serves as the concentrated point of resistance welding current hence the resistance welding can be efficiently performed. The unnecessary contact between the connection conductive element and electrode plate can be prevented. The productivity and volume energy density of the cell can be improved by increasing the number of windings.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for producing prismatic sealed secondary cell.    DESCRIPTION OF DRAWING(S) - The drawing shows the front view and side view of flat electrode assembly.    Output terminal (3)    Core exposed portion (5b)    Core exposed laminate (12')    Current collector plate portion (20)    Lead portion (20d)