NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PURPOSE:To increase the speed of sealing and to reduce costs by enclosing electrodes made from a material that stores and releases lithium and a nonaqueous electrolyte in a case whose sealing face has a specific aspect ratio, and achieving double winding. CONSTITUTION:A positive electrode made by a lithium-cobalt composite oxide, a negative electrode made by graphite, and a nonaqueous electrolyte containing lithium salts are enclosed in a battery case 3 and the case 3 is sealed using a sealing plate 4. The sealing surface of the battery case 3 is a face with the ratio of its long side to its short side 5 or higher and sealing is achieved by double winding. When the sealed portions of the battery case 3 which have different aspect ratios are sealed by double winding the speed of sealing is not affected by the overall peripheral length of the sealed portions but depends on the aspect ratios of the sealed portions. A nonaqueous secondary battery can then be manufactured at low cost with good mass productivity.