| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a secondary battery capable of suppressing deterioration in energy density. <P>SOLUTION: A secondary battery of the present invention includes: a positive electrode 2 containing a sulfur electrode active material and a conductive material; a negative electrode 3 arranged to face the positive electrode 2 at an interval therebetween; and a separator 4 interposed between the negative electrode 3 and the positive electrode 2. The separator 4 has a margin 7 located at a periphery of a projection plane of the positive electrode 2 when the positive electrode 2 is projected in the opposite direction of the positive electrode 2 and the negative electrode 3. The lower limit of a width orthogonal to the circumferential direction of the margin 7 is 0.5 mm or more, and the upper limit of the width is equivalent to the maximum width of a margin formed when the center of gravity of the positive electrode 2 and the center of gravity of the separator 4 are matched in the opposite direction of the positive electrode 2 and the negative electrode 3, while the positive electrode 2 and the separator 4 have a similar figure, and the area of the separator 4 is 2.56 times relative to the area of the positive electrode 2. <P>COPYRIGHT: (C)2012,JPO&INPIT |
