| 摘要 |
PURPOSE:To prevent a sheet-form PTC device from shortcircuiting and enhance the safety of a battery using the PTC device by cutting the PTC device into a specified shape by means of laser beam irradiation. CONSTITUTION:Polymeride in which carbon filler is dispersed, is shaped into a sheet to constitute a PTC element, and to each surface thereof an electrode plate is attached consisting of a metal sheet of nickel, SUS, copper, etc., having a thickness of 20-200mu, and thereby a sheet-form PTC device 5 is achieved. This device 5 is cut into a specified size by means of laser beam irradiation. The resultant product is free from burr production at the cut face of the device 5. The thickness of the electrode plate of this device 5 ranges 20-200mu, and material is selected from nickel, stainless steel, and steel plate, wherein the thickness of the PTC element becomes ranging 10-500mu. The laser beam used is of carbon dioxide gas type or TAG laser type, and the emissive output ranges 1-50W, and the cutting speed is made variable. |
