| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide: a separator not only capable of preventing the occurrence of a short circuit due to shrinkage or melting, but also hardly causing a short circuit due to dendrite of lithium, and further capable of manufacturing a lithium ion secondary battery excellent in high-rate discharge characteristics; and a lithium ion secondary battery manufactured using the separator. <P>SOLUTION: A separator for a lithium ion secondary battery of the present invention has a structure where a gap formed by the bond of fibers together is filled with inorganic particles. The separator has a porosity of 40% or greater and an air resistance (Gurley) of 100 seconds or greater, and includes an ultrafine fiber having a fiber diameter of 5 μm or less as a fiber, the ultrafine fiber having a core component comprising polypropylene and a sheath component comprising polyethylene. A lithium ion secondary battery is manufactured using the separator. <P>COPYRIGHT: (C)2013,JPO&INPIT |
