NOVELTY - The assembly (40) has a cap-up (80) having a groove (81) in an inner surface, and a positive temperature coefficient (PTC) thermistor (70) inserted into the groove, where inner components are disposed below the cap-up. The groove and the inner surface face the inner components, and the PTC thermistor is completely inserted into the groove, where the inner components comprise a current interrupt device (CID) (60) disposed below the cap-up and a vent (50) disposed below the CID. The CID contacts the inner surface of the cap-up, and is welded to the inner surface of the cap-up.    USE - Cap assembly for use in a secondary battery (claimed) i.e. lithium secondary battery such as can-type and pouch-type lithium secondary batteries, that is utilized as a power source for a portable electronic device e.g. cellular phone, notebook computer, and camcorder. Can also be used for nickel-cadmium, plumbum, nickel-hydrogen, lithium ion and lithium polymer secondary batteries.    ADVANTAGE - The cap-up is in direct contact with the current interrupt device, due to the insertion of the positive temperature coefficient thermistor into the cap-up, thus integrating the cap-up and the current interrupt device through welding. The thermistor is inserted into the groove of the cap-up, thus preventing increase of internal resistance due to contact among the components, and increasing the capacity of a cell by reducing the space occupied by the thermistor, while improving characteristics in controlling current flow.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a secondary battery comprising an electrode assembly and a can for housing the electrode assembly.    DESCRIPTION OF DRAWING(S) - The drawing shows an exploded perspective view illustrating a configuration of a secondary battery.    Inner insulating plate (11)    Center-pin (13)    Upper insulating plate (15)    Jelly-roll type electrode assembly (20)    Electrode tabs (27, 29)    Insulating gasket (30)    Cap assembly (40)    Vent (50)    Current interrupt device (60)    Positive temperature coefficient thermistor (70)    Cap-up (80)    Groove (81)