Radial-leaded over-current protection device

A radial-leaded over-current protection device, comprising:

• a PTC element comprising comprises a first conductive layer, a second conductive layer and a PTC material layer laminated therebetween;
• a first electrode lead having an end connecting to the first conductive layer;
• a second electrode lead having an end connecting to the second conductive layer;
• and an electrically insulating encapsulation layer, wherein the electrically insulating encapsulation layer comprises a fluorine-containing polymer, and wraps around an entire outer surface of the PTC element and the ends of the first and second electrodes connecting to the PTC element;
• wherein the electrically insulating encapsulation layer has a thickness of 102˜105 nm;
• wherein the radial-leaded over-current protection device has an initial resistance Rbf of 0.0017˜0.0027Ω;
• and
• wherein after being put in a high temperature and high humidity environment for 336 hours, the radial-leaded over-current protection device has a resistance recovery R % of 1.07-1.21, and an endurable current per unit area of the device of 0.85-1.10 A/mm2.