LITHIUMION POLYMER SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To obstruct the generation of cracks in a polymer electrolyte layer in manufacturing and in charge/discharge of a secondary battery and enhance energy density in the secondary battery. SOLUTION: A polymer electrolyte layer 17 is interposed between a positive active material layer 13 of a positive sheet 11 and a negative active material layer 16 of a negative sheet 17, and the positive sheet and the negative sheet are stacked. A laminate 20 is folded back once or two or more times in zigzag to form a lithium ion polymer secondary battery. A negative current collector foil 15, the polymer electrolyte layer, and a positive current collector foil 1 are folded back in belt, with no disconnection. The negative active material layer is formed on the negative current collector foil so that the folded part of the negative current collector foil is divided with a negative slit 18 and the positive active material layer is formed on the positive current collector foil so that the folded part of the positive current collector foil is divided with a positive slit 28.