NOVELTY - A PTC device (10) consists of a PTC element (22) and a lead (24). The PTC element consists of a layered polymer PTC element (12), and a PTC element comprising metal electrodes (18,20). At least a portion of the lead is placed on each of the metal electrodes in the PTC element, and is connected to the metal electrodes through an electroconductive material (28). An exposed portion of the electroconductive material is covered with a protective component (34) which comprises a material capable of absorbing or including an alkali.    USE - PTC device is used for secondary batteries (claimed) e.g. dry-cell type secondary batteries, and other electric devices.    ADVANTAGE - The PTC device provides compact secondary batteries. The protection component protects the exposed portion of electroconductive material from corrosion by alkali contained in electrolyte. The PTC device can function as a circuit protection element. The PTC device can be arranged in the positive electrode tab space of the secondary battery.    DETAILED DESCRIPTION - A PTC device consists of a PTC element and a lead. The PTC element consists of a layered polymer PTC element comprising an electroconductive filler and polymer material, and a PTC element comprising metal electrodes arranged on both surfaces (14,16) of the polymer PTC element. At least a portion of the lead is placed on each of the metal electrodes in the PTC element, and is connected to the metal electrodes through an electroconductive material. An exposed portion of the electroconductive material is covered with a protective component which comprises a material capable of absorbing or including an alkali. An INDEPENDENT CLAIM is included for secondary battery.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the PTC device.    PTC device (10)    Polymer PTC element (12)    Surfaces (14,16)    Metal electrodes (18,20)    PTC element (22)    Lead (24)    Electroconductive material (28)    Protective component (34)