| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which enables the further increase in the safety of a nonaqueous electrolyte secondary battery with the battery overcharged.SOLUTION: A nonaqueous electrolyte secondary battery comprises: a battery case; an electrode body provided in the battery case, and having positive and negative electrodes arranged so that a separator is interposed therebetween; a pressure-type current interrupt mechanism which interrupts charge/discharge current when the internal pressure of the battery case exceeds an operation pressure; and a nonaqueous electrolyte held by at least the separator, and including a gas generating agent which generates gas on condition that the potential of the positive electrode exceeds a gas generation potential. The positive electrode has a positive electrode-exposed part formed by exposing a positive electrode collector from a positive electrode mixture layer at one end in a widthwise direction. At least a part of an end face of the positive electrode mixture layer on the side of the positive electrode-exposed part is formed to have an uneven shape. In a region of the positive electrode where the end face of the positive electrode mixture layer is formed to have an uneven shape, the length of the end face of the positive electrode mixture layer along the uneven shape is equal to or larger than 1.2 times the length of the positive electrode in a longitudinal direction of the positive electrode. |
