| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery preventing a large electric current from flowing between electrodes even if nail sticking and a collapse are caused and enhancing stability by providing ion permeability on at least either one surface of a positive electrode and a negative electrode, and forming a coating film layer having a specific tensile elongation percentage. SOLUTION: A coating film layer having a tensile elongation percentage not less than 200% is formed. Desirably, the coating film layer has heat resistance not less than 150 deg.C, and the coating film layer is a fluorine high molecular compound. The coating film layer contains a filler. The filler is desirably a single body of calcium carbonate, magnesium carbonate, magnesium oxide and aluminum oxide or a mixture of these. A positive electrode 1 and a negative electrode 2 are wound through a separator 3 to form a winding type power generation element. For example, even if a metallic bar 5 is stuck and penetrated through the positive electrode 1 and the negative electrode 2, the coating film layer 4 enongates to cover the side surface of the metallic bar 5. The coating film layer 4 is extremely low in electric conductivity to prevent a short- circuit current from flowing between the positive/negative electrodes 1, 2. |
