| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a battery capable of suppressing internal short circuit. <P>SOLUTION: The negative electrode 22 contains a negative electrode active material containing Sn or Si as a constituent element. The separator 23 has a piercing strength of 4.0 N or more and 9.8 N or less with the thickness value converted in 20 μm, and a tensile strength in winding axial direction of 40 MPa or more and 150 MPa or less. Thereby, even if the negative electrode active material is greatly expanded and shrunken at the charge and discharge, damage to the separator 23 is suppressed and internal short circuit is suppressed. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
