Electrode tab for a nonaqueous electrolyte secondary battery and method of forming the same

摘要

A nonaqueous electrolyte secondary battery having a cylindrically shaped battery element includes positive and negative electrodes and a separator sandwiched between the positive and negative electrodes. Each of the positive and negative electrodes has an active material free region, on which no active material is applied. The active material free region has a projecting edge region which projects or extends beyond a first side edge of the separator, wherein a first end of the cylindrically shaped battery element includes the projecting edge region of the active material free region of one of the positive and negative electrodes, and the first end of the cylindrically shaped battery element has a depressed portion. An electrode tab has a first portion engaged within and welded to the depressed portion and a second portion electrically in contact with an electrode terminal.