| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery which has excellent cycle characteristics in case charge/discharge cycles are conducted under a charging voltage of 4.25 V or more and 6.00 V or less. <P>SOLUTION: The lithium ion secondary battery is composed of a cathode 2 having an active substance and a binder, an anode 3, and an electrolyte as well as a separator 4 positioned between the cathode 2 and the anode 3, and an open circuit voltage per a unit cell in a full charge is 4.25 V or more and 6.00 V or less. For such a lithium ion secondary battery, a binder containing polyacrylonitrile group resin is used to obtain excellent cycle characteristics. <P>COPYRIGHT: (C)2007,JPO&INPIT |
